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Commit 736a2dd2 authored by Linus Torvalds's avatar Linus Torvalds
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux 

Pull virtio & lguest updates from Rusty Russell:
 "Lots of virtio work which wasn't quite ready for last merge window.

  Plus I dived into lguest again, reworking the pagetable code so we can
  move the switcher page: our fixmaps sometimes take more than 2MB now..."

Ugh.  Annoying conflicts with the tcm_vhost -> vhost_scsi rename.
Hopefully correctly resolved.

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (57 commits)
  caif_virtio: Remove bouncing email addresses
  lguest: improve code readability in lg_cpu_start.
  virtio-net: fill only rx queues which are being used
  lguest: map Switcher below fixmap.
  lguest: cache last cpu we ran on.
  lguest: map Switcher text whenever we allocate a new pagetable.
  lguest: don't share Switcher PTE pages between guests.
  lguest: expost switcher_pages array (as lg_switcher_pages).
  lguest: extract shadow PTE walking / allocating.
  lguest: make check_gpte et. al return bool.
  lguest: assume Switcher text is a single page.
  lguest: rename switcher_page to switcher_pages.
  lguest: remove RESERVE_MEM constant.
  lguest: check vaddr not pgd for Switcher protection.
  lguest: prepare to make SWITCHER_ADDR a variable.
  virtio: console: replace EMFILE with EBUSY for already-open port
  virtio-scsi: reset virtqueue affinity when doing cpu hotplug
  virtio-scsi: introduce multiqueue support
  virtio-scsi: push vq lock/unlock into virtscsi_vq_done
  virtio-scsi: pass struct virtio_scsi to virtqueue completion function
  ...
parents 0b2e3b6b 01d779a1
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Documentation/virtual/00-INDEX
View file @ 736a2dd2
......@@ -6,6 +6,3 @@ kvm/
- Kernel Virtual Machine. See also http://linux-kvm.org
uml/
- User Mode Linux, builds/runs Linux kernel as a userspace program.
virtio.txt
- Text version of draft virtio spec.
See http://ozlabs.org/~rusty/virtio-spec
Documentation/virtual/virtio-spec.txt deleted 100644 → 0
View file @ 0b2e3b6b
This source diff could not be displayed because it is too large. You can view the blob instead.
MAINTAINERS
View file @ 736a2dd2
......@@ -8743,6 +8743,7 @@ F: drivers/virtio/
F: drivers/net/virtio_net.c
F: drivers/block/virtio_blk.c
F: include/linux/virtio_*.h
F: include/uapi/linux/virtio_*.h
VIRTIO HOST (VHOST)
M: "Michael S. Tsirkin" <mst@redhat.com>
......
arch/x86/include/asm/lguest.h
View file @ 736a2dd2
......@@ -11,18 +11,11 @@
#define GUEST_PL 1
/* Every guest maps the core switcher code. */
#define SHARED_SWITCHER_PAGES \
DIV_ROUND_UP(end_switcher_text - start_switcher_text, PAGE_SIZE)
/* Pages for switcher itself, then two pages per cpu */
#define TOTAL_SWITCHER_PAGES (SHARED_SWITCHER_PAGES + 2 * nr_cpu_ids)
/* We map at -4M (-2M for PAE) for ease of mapping (one PTE page). */
#ifdef CONFIG_X86_PAE
#define SWITCHER_ADDR 0xFFE00000
#else
#define SWITCHER_ADDR 0xFFC00000
#endif
/* Page for Switcher text itself, then two pages per cpu */
#define TOTAL_SWITCHER_PAGES (1 + 2 * nr_cpu_ids)
/* Where we map the Switcher, in both Host and Guest. */
extern unsigned long switcher_addr;
/* Found in switcher.S */
extern unsigned long default_idt_entries[];
......
block/blk-integrity.c
View file @ 736a2dd2
......@@ -110,7 +110,7 @@ int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio,
if (!sg)
sg = sglist;
else {
sg->page_link &= ~0x02;
sg_unmark_end(sg);
sg = sg_next(sg);
}
......
block/blk-merge.c
View file @ 736a2dd2
......@@ -143,7 +143,7 @@ __blk_segment_map_sg(struct request_queue *q, struct bio_vec *bvec,
* termination bit to avoid doing a full
* sg_init_table() in drivers for each command.
*/
(*sg)->page_link &= ~0x02;
sg_unmark_end(*sg);
*sg = sg_next(*sg);
}
......
drivers/Makefile
View file @ 736a2dd2
......@@ -124,7 +124,7 @@ obj-$(CONFIG_PPC_PS3) += ps3/
obj-$(CONFIG_OF) += of/
obj-$(CONFIG_SSB) += ssb/
obj-$(CONFIG_BCMA) += bcma/
obj-$(CONFIG_VHOST_NET) += vhost/
obj-$(CONFIG_VHOST_RING) += vhost/
obj-$(CONFIG_VLYNQ) += vlynq/
obj-$(CONFIG_STAGING) += staging/
obj-y += platform/
......
drivers/block/virtio_blk.c
View file @ 736a2dd2
......@@ -100,96 +100,103 @@ static inline struct virtblk_req *virtblk_alloc_req(struct virtio_blk *vblk,
return vbr;
}
static void virtblk_add_buf_wait(struct virtio_blk *vblk,
struct virtblk_req *vbr,
unsigned long out,
unsigned long in)
static int __virtblk_add_req(struct virtqueue *vq,
struct virtblk_req *vbr,
struct scatterlist *data_sg,
bool have_data)
{
DEFINE_WAIT(wait);
struct scatterlist hdr, status, cmd, sense, inhdr, *sgs[6];
unsigned int num_out = 0, num_in = 0;
int type = vbr->out_hdr.type & ~VIRTIO_BLK_T_OUT;
for (;;) {
prepare_to_wait_exclusive(&vblk->queue_wait, &wait,
TASK_UNINTERRUPTIBLE);
sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr));
sgs[num_out++] = &hdr;
spin_lock_irq(vblk->disk->queue->queue_lock);
if (virtqueue_add_buf(vblk->vq, vbr->sg, out, in, vbr,
GFP_ATOMIC) < 0) {
spin_unlock_irq(vblk->disk->queue->queue_lock);
io_schedule();
} else {
virtqueue_kick(vblk->vq);
spin_unlock_irq(vblk->disk->queue->queue_lock);
break;
}
/*
* If this is a packet command we need a couple of additional headers.
* Behind the normal outhdr we put a segment with the scsi command
* block, and before the normal inhdr we put the sense data and the
* inhdr with additional status information.
*/
if (type == VIRTIO_BLK_T_SCSI_CMD) {
sg_init_one(&cmd, vbr->req->cmd, vbr->req->cmd_len);
sgs[num_out++] = &cmd;
}
if (have_data) {
if (vbr->out_hdr.type & VIRTIO_BLK_T_OUT)
sgs[num_out++] = data_sg;
else
sgs[num_out + num_in++] = data_sg;
}
finish_wait(&vblk->queue_wait, &wait);
if (type == VIRTIO_BLK_T_SCSI_CMD) {
sg_init_one(&sense, vbr->req->sense, SCSI_SENSE_BUFFERSIZE);
sgs[num_out + num_in++] = &sense;
sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr));
sgs[num_out + num_in++] = &inhdr;
}
sg_init_one(&status, &vbr->status, sizeof(vbr->status));
sgs[num_out + num_in++] = &status;
return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC);
}
static inline void virtblk_add_req(struct virtblk_req *vbr,
unsigned int out, unsigned int in)
static void virtblk_add_req(struct virtblk_req *vbr, bool have_data)
{
struct virtio_blk *vblk = vbr->vblk;
DEFINE_WAIT(wait);
int ret;
spin_lock_irq(vblk->disk->queue->queue_lock);
if (unlikely(virtqueue_add_buf(vblk->vq, vbr->sg, out, in, vbr,
GFP_ATOMIC) < 0)) {
while (unlikely((ret = __virtblk_add_req(vblk->vq, vbr, vbr->sg,
have_data)) < 0)) {
prepare_to_wait_exclusive(&vblk->queue_wait, &wait,
TASK_UNINTERRUPTIBLE);
spin_unlock_irq(vblk->disk->queue->queue_lock);
virtblk_add_buf_wait(vblk, vbr, out, in);
return;
io_schedule();
spin_lock_irq(vblk->disk->queue->queue_lock);
finish_wait(&vblk->queue_wait, &wait);
}
virtqueue_kick(vblk->vq);
spin_unlock_irq(vblk->disk->queue->queue_lock);
}
static int virtblk_bio_send_flush(struct virtblk_req *vbr)
static void virtblk_bio_send_flush(struct virtblk_req *vbr)
{
unsigned int out = 0, in = 0;
vbr->flags |= VBLK_IS_FLUSH;
vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH;
vbr->out_hdr.sector = 0;
vbr->out_hdr.ioprio = 0;
sg_set_buf(&vbr->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));
sg_set_buf(&vbr->sg[out + in++], &vbr->status, sizeof(vbr->status));
virtblk_add_req(vbr, out, in);
return 0;
virtblk_add_req(vbr, false);
}
static int virtblk_bio_send_data(struct virtblk_req *vbr)
static void virtblk_bio_send_data(struct virtblk_req *vbr)
{
struct virtio_blk *vblk = vbr->vblk;
unsigned int num, out = 0, in = 0;
struct bio *bio = vbr->bio;
bool have_data;
vbr->flags &= ~VBLK_IS_FLUSH;
vbr->out_hdr.type = 0;
vbr->out_hdr.sector = bio->bi_sector;
vbr->out_hdr.ioprio = bio_prio(bio);
sg_set_buf(&vbr->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));
num = blk_bio_map_sg(vblk->disk->queue, bio, vbr->sg + out);
sg_set_buf(&vbr->sg[num + out + in++], &vbr->status,
sizeof(vbr->status));
if (num) {
if (bio->bi_rw & REQ_WRITE) {
if (blk_bio_map_sg(vblk->disk->queue, bio, vbr->sg)) {
have_data = true;
if (bio->bi_rw & REQ_WRITE)
vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
out += num;
} else {
else
vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
in += num;
}
}
} else
have_data = false;
virtblk_add_req(vbr, out, in);
return 0;
virtblk_add_req(vbr, have_data);
}
static void virtblk_bio_send_data_work(struct work_struct *work)
......@@ -298,7 +305,7 @@ static void virtblk_done(struct virtqueue *vq)
static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
struct request *req)
{
unsigned long num, out = 0, in = 0;
unsigned int num;
struct virtblk_req *vbr;
vbr = virtblk_alloc_req(vblk, GFP_ATOMIC);
......@@ -335,40 +342,15 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
}
}
sg_set_buf(&vblk->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));
/*
* If this is a packet command we need a couple of additional headers.
* Behind the normal outhdr we put a segment with the scsi command
* block, and before the normal inhdr we put the sense data and the
* inhdr with additional status information before the normal inhdr.
*/
if (vbr->req->cmd_type == REQ_TYPE_BLOCK_PC)
sg_set_buf(&vblk->sg[out++], vbr->req->cmd, vbr->req->cmd_len);
num = blk_rq_map_sg(q, vbr->req, vblk->sg + out);
if (vbr->req->cmd_type == REQ_TYPE_BLOCK_PC) {
sg_set_buf(&vblk->sg[num + out + in++], vbr->req->sense, SCSI_SENSE_BUFFERSIZE);
sg_set_buf(&vblk->sg[num + out + in++], &vbr->in_hdr,
sizeof(vbr->in_hdr));
}
sg_set_buf(&vblk->sg[num + out + in++], &vbr->status,
sizeof(vbr->status));
num = blk_rq_map_sg(q, vbr->req, vblk->sg);
if (num) {
if (rq_data_dir(vbr->req) == WRITE) {
if (rq_data_dir(vbr->req) == WRITE)
vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
out += num;
} else {
else
vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
in += num;
}
}
if (virtqueue_add_buf(vblk->vq, vblk->sg, out, in, vbr,
GFP_ATOMIC) < 0) {
if (__virtblk_add_req(vblk->vq, vbr, vblk->sg, num) < 0) {
mempool_free(vbr, vblk->pool);
return false;
}
......@@ -539,6 +521,7 @@ static void virtblk_config_changed_work(struct work_struct *work)
struct virtio_device *vdev = vblk->vdev;
struct request_queue *q = vblk->disk->queue;
char cap_str_2[10], cap_str_10[10];
char *envp[] = { "RESIZE=1", NULL };
u64 capacity, size;
mutex_lock(&vblk->config_lock);
......@@ -568,6 +551,7 @@ static void virtblk_config_changed_work(struct work_struct *work)
set_capacity(vblk->disk, capacity);
revalidate_disk(vblk->disk);
kobject_uevent_env(&disk_to_dev(vblk->disk)->kobj, KOBJ_CHANGE, envp);
done:
mutex_unlock(&vblk->config_lock);
}
......
drivers/char/hw_random/virtio-rng.c
View file @ 736a2dd2
......@@ -47,7 +47,7 @@ static void register_buffer(u8 *buf, size_t size)
sg_init_one(&sg, buf, size);
/* There should always be room for one buffer. */
if (virtqueue_add_buf(vq, &sg, 0, 1, buf, GFP_KERNEL) < 0)
if (virtqueue_add_inbuf(vq, &sg, 1, buf, GFP_KERNEL) < 0)
BUG();
virtqueue_kick(vq);
......
drivers/char/virtio_console.c
View file @ 736a2dd2
......@@ -78,8 +78,8 @@ struct ports_driver_data {
};
static struct ports_driver_data pdrvdata;
DEFINE_SPINLOCK(pdrvdata_lock);
DECLARE_COMPLETION(early_console_added);
static DEFINE_SPINLOCK(pdrvdata_lock);
static DECLARE_COMPLETION(early_console_added);
/* This struct holds information that's relevant only for console ports */
struct console {
......@@ -503,7 +503,7 @@ static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
sg_init_one(sg, buf->buf, buf->size);
ret = virtqueue_add_buf(vq, sg, 0, 1, buf, GFP_ATOMIC);
ret = virtqueue_add_inbuf(vq, sg, 1, buf, GFP_ATOMIC);
virtqueue_kick(vq);
if (!ret)
ret = vq->num_free;
......@@ -572,7 +572,7 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
sg_init_one(sg, &cpkt, sizeof(cpkt));
spin_lock(&portdev->c_ovq_lock);
if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) == 0) {
if (virtqueue_add_outbuf(vq, sg, 1, &cpkt, GFP_ATOMIC) == 0) {
virtqueue_kick(vq);
while (!virtqueue_get_buf(vq, &len))
cpu_relax();
......@@ -622,7 +622,7 @@ static ssize_t __send_to_port(struct port *port, struct scatterlist *sg,
reclaim_consumed_buffers(port);
err = virtqueue_add_buf(out_vq, sg, nents, 0, data, GFP_ATOMIC);
err = virtqueue_add_outbuf(out_vq, sg, nents, data, GFP_ATOMIC);
/* Tell Host to go! */
virtqueue_kick(out_vq);
......@@ -1040,7 +1040,7 @@ static int port_fops_open(struct inode *inode, struct file *filp)
spin_lock_irq(&port->inbuf_lock);
if (port->guest_connected) {
spin_unlock_irq(&port->inbuf_lock);
ret = -EMFILE;
ret = -EBUSY;
goto out;
}
......@@ -1202,7 +1202,7 @@ int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
return hvc_instantiate(0, 0, &hv_ops);
}
int init_port_console(struct port *port)
static int init_port_console(struct port *port)
{
int ret;
......
drivers/lguest/Kconfig
View file @ 736a2dd2
......@@ -5,10 +5,9 @@ config LGUEST
---help---
This is a very simple module which allows you to run
multiple instances of the same Linux kernel, using the
"lguest" command found in the Documentation/virtual/lguest
directory.
"lguest" command found in the tools/lguest directory.
Note that "lguest" is pronounced to rhyme with "fell quest",
not "rustyvisor". See Documentation/virtual/lguest/lguest.txt.
not "rustyvisor". See tools/lguest/lguest.txt.
If unsure, say N. If curious, say M. If masochistic, say Y.
drivers/lguest/core.c
View file @ 736a2dd2
......@@ -20,9 +20,9 @@
#include <asm/asm-offsets.h>
#include "lg.h"
unsigned long switcher_addr;
struct page **lg_switcher_pages;
static struct vm_struct *switcher_vma;
static struct page **switcher_page;
/* This One Big lock protects all inter-guest data structures. */
DEFINE_MUTEX(lguest_lock);
......@@ -52,13 +52,21 @@ static __init int map_switcher(void)
* easy.
*/
/* We assume Switcher text fits into a single page. */
if (end_switcher_text - start_switcher_text > PAGE_SIZE) {
printk(KERN_ERR "lguest: switcher text too large (%zu)\n",
end_switcher_text - start_switcher_text);
return -EINVAL;
}
/*
* We allocate an array of struct page pointers. map_vm_area() wants
* this, rather than just an array of pages.
*/
switcher_page = kmalloc(sizeof(switcher_page[0])*TOTAL_SWITCHER_PAGES,
GFP_KERNEL);
if (!switcher_page) {
lg_switcher_pages = kmalloc(sizeof(lg_switcher_pages[0])
* TOTAL_SWITCHER_PAGES,
GFP_KERNEL);
if (!lg_switcher_pages) {
err = -ENOMEM;
goto out;
}
......@@ -68,32 +76,29 @@ static __init int map_switcher(void)
* so we make sure they're zeroed.
*/
for (i = 0; i < TOTAL_SWITCHER_PAGES; i++) {
switcher_page[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
if (!switcher_page[i]) {
lg_switcher_pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
if (!lg_switcher_pages[i]) {
err = -ENOMEM;
goto free_some_pages;
}
}
/*
* First we check that the Switcher won't overlap the fixmap area at
* the top of memory. It's currently nowhere near, but it could have
* very strange effects if it ever happened.
* We place the Switcher underneath the fixmap area, which is the
* highest virtual address we can get. This is important, since we
* tell the Guest it can't access this memory, so we want its ceiling
* as high as possible.
*/
if (SWITCHER_ADDR + (TOTAL_SWITCHER_PAGES+1)*PAGE_SIZE > FIXADDR_START){
err = -ENOMEM;
printk("lguest: mapping switcher would thwack fixmap\n");
goto free_pages;
}
switcher_addr = FIXADDR_START - (TOTAL_SWITCHER_PAGES+1)*PAGE_SIZE;
/*
* Now we reserve the "virtual memory area" we want: 0xFFC00000
* (SWITCHER_ADDR). We might not get it in theory, but in practice
* it's worked so far. The end address needs +1 because __get_vm_area
* allocates an extra guard page, so we need space for that.
* Now we reserve the "virtual memory area" we want. We might
* not get it in theory, but in practice it's worked so far.
* The end address needs +1 because __get_vm_area allocates an
* extra guard page, so we need space for that.
*/
switcher_vma = __get_vm_area(TOTAL_SWITCHER_PAGES * PAGE_SIZE,
VM_ALLOC, SWITCHER_ADDR, SWITCHER_ADDR
VM_ALLOC, switcher_addr, switcher_addr
+ (TOTAL_SWITCHER_PAGES+1) * PAGE_SIZE);
if (!switcher_vma) {
err = -ENOMEM;
......@@ -103,12 +108,12 @@ static __init int map_switcher(void)
/*
* This code actually sets up the pages we've allocated to appear at
* SWITCHER_ADDR. map_vm_area() takes the vma we allocated above, the
* switcher_addr. map_vm_area() takes the vma we allocated above, the
* kind of pages we're mapping (kernel pages), and a pointer to our
* array of struct pages. It increments that pointer, but we don't
* care.
*/
pagep = switcher_page;
pagep = lg_switcher_pages;
err = map_vm_area(switcher_vma, PAGE_KERNEL_EXEC, &pagep);
if (err) {
printk("lguest: map_vm_area failed: %i\n", err);
......@@ -133,8 +138,8 @@ static __init int map_switcher(void)
i = TOTAL_SWITCHER_PAGES;
free_some_pages:
for (--i; i >= 0; i--)
__free_pages(switcher_page[i], 0);
kfree(switcher_page);
__free_pages(lg_switcher_pages[i], 0);
kfree(lg_switcher_pages);
out:
return err;
}
......@@ -149,8 +154,8 @@ static void unmap_switcher(void)
vunmap(switcher_vma->addr);
/* Now we just need to free the pages we copied the switcher into */
for (i = 0; i < TOTAL_SWITCHER_PAGES; i++)
__free_pages(switcher_page[i], 0);
kfree(switcher_page);
__free_pages(lg_switcher_pages[i], 0);
kfree(lg_switcher_pages);
}
/*H:032
......@@ -323,15 +328,10 @@ static int __init init(void)
if (err)
goto out;
/* Now we set up the pagetable implementation for the Guests. */
err = init_pagetables(switcher_page, SHARED_SWITCHER_PAGES);
if (err)
goto unmap;
/* We might need to reserve an interrupt vector. */
err = init_interrupts();
if (err)
goto free_pgtables;
goto unmap;
/* /dev/lguest needs to be registered. */
err = lguest_device_init();
......@@ -346,8 +346,6 @@ static int __init init(void)
free_interrupts:
free_interrupts();
free_pgtables:
free_pagetables();
unmap:
unmap_switcher();
out:
......@@ -359,7 +357,6 @@ static void __exit fini(void)
{
lguest_device_remove();
free_interrupts();
free_pagetables();
unmap_switcher();
lguest_arch_host_fini();
......
drivers/lguest/lg.h
View file @ 736a2dd2
......@@ -14,11 +14,10 @@
#include <asm/lguest.h>
void free_pagetables(void);
int init_pagetables(struct page **switcher_page, unsigned int pages);
struct pgdir {
unsigned long gpgdir;
bool switcher_mapped;
int last_host_cpu;
pgd_t *pgdir;
};
......@@ -124,6 +123,7 @@ bool lguest_address_ok(const struct lguest *lg,
unsigned long addr, unsigned long len);
void __lgread(struct lg_cpu *, void *, unsigned long, unsigned);
void __lgwrite(struct lg_cpu *, unsigned long, const void *, unsigned);
extern struct page **lg_switcher_pages;
/*H:035
* Using memory-copy operations like that is usually inconvient, so we
......
drivers/lguest/lguest_user.c
View file @ 736a2dd2
......@@ -250,13 +250,13 @@ static ssize_t read(struct file *file, char __user *user, size_t size,loff_t*o)
*/
static int lg_cpu_start(struct lg_cpu *cpu, unsigned id, unsigned long start_ip)
{
/* We have a limited number the number of CPUs in the lguest struct. */
/* We have a limited number of CPUs in the lguest struct. */
if (id >= ARRAY_SIZE(cpu->lg->cpus))
return -EINVAL;
/* Set up this CPU's id, and pointer back to the lguest struct. */
cpu->id = id;
cpu->lg = container_of((cpu - id), struct lguest, cpus[0]);
cpu->lg = container_of(cpu, struct lguest, cpus[id]);
cpu->lg->nr_cpus++;
/* Each CPU has a timer it can set. */
......@@ -270,7 +270,7 @@ static int lg_cpu_start(struct lg_cpu *cpu, unsigned id, unsigned long start_ip)
if (!cpu->regs_page)
return -ENOMEM;
/* We actually put the registers at the bottom of the page. */
/* We actually put the registers at the end of the page. */
cpu->regs = (void *)cpu->regs_page + PAGE_SIZE - sizeof(*cpu->regs);
/*
......
drivers/lguest/page_tables.c
View file @ 736a2dd2
......@@ -7,7 +7,7 @@
* converted Guest pages when running the Guest.
:*/
/* Copyright (C) Rusty Russell IBM Corporation 2006.
/* Copyright (C) Rusty Russell IBM Corporation 2013.
* GPL v2 and any later version */
#include <linux/mm.h>
#include <linux/gfp.h>
......@@ -62,22 +62,11 @@
* will need the last pmd entry of the last pmd page.
*/
#ifdef CONFIG_X86_PAE
#define SWITCHER_PMD_INDEX (PTRS_PER_PMD - 1)
#define RESERVE_MEM 2U
#define CHECK_GPGD_MASK _PAGE_PRESENT
#else
#define RESERVE_MEM 4U
#define CHECK_GPGD_MASK _PAGE_TABLE
#endif
/*
* We actually need a separate PTE page for each CPU. Remember that after the
* Switcher code itself comes two pages for each CPU, and we don't want this
* CPU's guest to see the pages of any other CPU.
*/
static DEFINE_PER_CPU(pte_t *, switcher_pte_pages);
#define switcher_pte_page(cpu) per_cpu(switcher_pte_pages, cpu)
/*H:320
* The page table code is curly enough to need helper functions to keep it
* clear and clean. The kernel itself provides many of them; one advantage
......@@ -95,13 +84,6 @@ static pgd_t *spgd_addr(struct lg_cpu *cpu, u32 i, unsigned long vaddr)
{
unsigned int index = pgd_index(vaddr);
#ifndef CONFIG_X86_PAE
/* We kill any Guest trying to touch the Switcher addresses. */
if (index >= SWITCHER_PGD_INDEX) {
kill_guest(cpu, "attempt to access switcher pages");
index = 0;
}
#endif
/* Return a pointer index'th pgd entry for the i'th page table. */
return &cpu->lg->pgdirs[i].pgdir[index];
}
......@@ -117,13 +99,6 @@ static pmd_t *spmd_addr(struct lg_cpu *cpu, pgd_t spgd, unsigned long vaddr)
unsigned int index = pmd_index(vaddr);
pmd_t *page;
/* We kill any Guest trying to touch the Switcher addresses. */
if (pgd_index(vaddr) == SWITCHER_PGD_INDEX &&
index >= SWITCHER_PMD_INDEX) {
kill_guest(cpu, "attempt to access switcher pages");
index = 0;
}
/* You should never call this if the PGD entry wasn't valid */
BUG_ON(!(pgd_flags(spgd) & _PAGE_PRESENT));
page = __va(pgd_pfn(spgd) << PAGE_SHIFT);
......@@ -275,122 +250,177 @@ static void release_pte(pte_t pte)
}
/*:*/
static void check_gpte(struct lg_cpu *cpu, pte_t gpte)
static bool check_gpte(struct lg_cpu *cpu, pte_t gpte)
{
if ((pte_flags(gpte) & _PAGE_PSE) ||
pte_pfn(gpte) >= cpu->lg->pfn_limit)
pte_pfn(gpte) >= cpu->lg->pfn_limit) {
kill_guest(cpu, "bad page table entry");
return false;
}
return true;
}
static void check_gpgd(struct lg_cpu *cpu, pgd_t gpgd)
static bool check_gpgd(struct lg_cpu *cpu, pgd_t gpgd)
{
if ((pgd_flags(gpgd) & ~CHECK_GPGD_MASK) ||
(pgd_pfn(gpgd) >= cpu->lg->pfn_limit))
(pgd_pfn(gpgd) >= cpu->lg->pfn_limit)) {
kill_guest(cpu, "bad page directory entry");
return false;
}
return true;
}
#ifdef CONFIG_X86_PAE
static void check_gpmd(struct lg_cpu *cpu, pmd_t gpmd)
static bool check_gpmd(struct lg_cpu *cpu, pmd_t gpmd)
{
if ((pmd_flags(gpmd) & ~_PAGE_TABLE) ||
(pmd_pfn(gpmd) >= cpu->lg->pfn_limit))
(pmd_pfn(gpmd) >= cpu->lg->pfn_limit)) {
kill_guest(cpu, "bad page middle directory entry");
return false;
}
return true;
}
#endif
/*H:330
* (i) Looking up a page table entry when the Guest faults.
*
* We saw this call in run_guest(): when we see a page fault in the Guest, we
* come here. That's because we only set up the shadow page tables lazily as
* they're needed, so we get page faults all the time and quietly fix them up
* and return to the Guest without it knowing.
/*H:331
* This is the core routine to walk the shadow page tables and find the page
* table entry for a specific address.
*
* If we fixed up the fault (ie. we mapped the address), this routine returns
* true. Otherwise, it was a real fault and we need to tell the Guest.
* If allocate is set, then we allocate any missing levels, setting the flags
* on the new page directory and mid-level directories using the arguments
* (which are copied from the Guest's page table entries).
*/
bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
static pte_t *find_spte(struct lg_cpu *cpu, unsigned long vaddr, bool allocate,
int pgd_flags, int pmd_flags)
{
pgd_t gpgd;
pgd_t *spgd;
unsigned long gpte_ptr;
pte_t gpte;
pte_t *spte;
/* Mid level for PAE. */
#ifdef CONFIG_X86_PAE
pmd_t *spmd;
pmd_t gpmd;
#endif
/* First step: get the top-level Guest page table entry. */
if (unlikely(cpu->linear_pages)) {
/* Faking up a linear mapping. */
gpgd = __pgd(CHECK_GPGD_MASK);
} else {
gpgd = lgread(cpu, gpgd_addr(cpu, vaddr), pgd_t);
/* Toplevel not present? We can't map it in. */
if (!(pgd_flags(gpgd) & _PAGE_PRESENT))
return false;
}
/* Now look at the matching shadow entry. */
/* Get top level entry. */
spgd = spgd_addr(cpu, cpu->cpu_pgd, vaddr);
if (!(pgd_flags(*spgd) & _PAGE_PRESENT)) {
/* No shadow entry: allocate a new shadow PTE page. */
unsigned long ptepage = get_zeroed_page(GFP_KERNEL);
unsigned long ptepage;
/* If they didn't want us to allocate anything, stop. */
if (!allocate)
return NULL;
ptepage = get_zeroed_page(GFP_KERNEL);
/*
* This is not really the Guest's fault, but killing it is
* simple for this corner case.
*/
if (!ptepage) {
kill_guest(cpu, "out of memory allocating pte page");
return false;
return NULL;
}
/* We check that the Guest pgd is OK. */
check_gpgd(cpu, gpgd);
/*
* And we copy the flags to the shadow PGD entry. The page
* number in the shadow PGD is the page we just allocated.
*/
set_pgd(spgd, __pgd(__pa(ptepage) | pgd_flags(gpgd)));
set_pgd(spgd, __pgd(__pa(ptepage) | pgd_flags));
}
/*
* Intel's Physical Address Extension actually uses three levels of
* page tables, so we need to look in the mid-level.
*/
#ifdef CONFIG_X86_PAE
if (unlikely(cpu->linear_pages)) {
/* Faking up a linear mapping. */
gpmd = __pmd(_PAGE_TABLE);
} else {
gpmd = lgread(cpu, gpmd_addr(gpgd, vaddr), pmd_t);
/* Middle level not present? We can't map it in. */
if (!(pmd_flags(gpmd) & _PAGE_PRESENT))
return false;
}
/* Now look at the matching shadow entry. */
/* Now look at the mid-level shadow entry. */
spmd = spmd_addr(cpu, *spgd, vaddr);
if (!(pmd_flags(*spmd) & _PAGE_PRESENT)) {
/* No shadow entry: allocate a new shadow PTE page. */
unsigned long ptepage = get_zeroed_page(GFP_KERNEL);
unsigned long ptepage;
/* If they didn't want us to allocate anything, stop. */
if (!allocate)
return NULL;
ptepage = get_zeroed_page(GFP_KERNEL);
/*
* This is not really the Guest's fault, but killing it is
* simple for this corner case.
*/
if (!ptepage) {
kill_guest(cpu, "out of memory allocating pte page");
return false;
kill_guest(cpu, "out of memory allocating pmd page");
return NULL;
}
/* We check that the Guest pmd is OK. */
check_gpmd(cpu, gpmd);
/*
* And we copy the flags to the shadow PMD entry. The page
* number in the shadow PMD is the page we just allocated.
*/
set_pmd(spmd, __pmd(__pa(ptepage) | pmd_flags(gpmd)));
set_pmd(spmd, __pmd(__pa(ptepage) | pmd_flags));
}
#endif
/* Get the pointer to the shadow PTE entry we're going to set. */
return spte_addr(cpu, *spgd, vaddr);
}
/*H:330
* (i) Looking up a page table entry when the Guest faults.
*
* We saw this call in run_guest(): when we see a page fault in the Guest, we
* come here. That's because we only set up the shadow page tables lazily as
* they're needed, so we get page faults all the time and quietly fix them up
* and return to the Guest without it knowing.
*
* If we fixed up the fault (ie. we mapped the address), this routine returns
* true. Otherwise, it was a real fault and we need to tell the Guest.
*/
bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
{
unsigned long gpte_ptr;
pte_t gpte;
pte_t *spte;
pmd_t gpmd;
pgd_t gpgd;
/* We never demand page the Switcher, so trying is a mistake. */
if (vaddr >= switcher_addr)
return false;
/* First step: get the top-level Guest page table entry. */
if (unlikely(cpu->linear_pages)) {
/* Faking up a linear mapping. */
gpgd = __pgd(CHECK_GPGD_MASK);
} else {
gpgd = lgread(cpu, gpgd_addr(cpu, vaddr), pgd_t);
/* Toplevel not present? We can't map it in. */
if (!(pgd_flags(gpgd) & _PAGE_PRESENT))
return false;
/*
* This kills the Guest if it has weird flags or tries to
* refer to a "physical" address outside the bounds.
*/
if (!check_gpgd(cpu, gpgd))
return false;
}
/* This "mid-level" entry is only used for non-linear, PAE mode. */
gpmd = __pmd(_PAGE_TABLE);
#ifdef CONFIG_X86_PAE
if (likely(!cpu->linear_pages)) {
gpmd = lgread(cpu, gpmd_addr(gpgd, vaddr), pmd_t);
/* Middle level not present? We can't map it in. */
if (!(pmd_flags(gpmd) & _PAGE_PRESENT))
return false;
/*
* This kills the Guest if it has weird flags or tries to
* refer to a "physical" address outside the bounds.
*/
if (!check_gpmd(cpu, gpmd))
return false;
}
/*
......@@ -433,7 +463,8 @@ bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
* Check that the Guest PTE flags are OK, and the page number is below
* the pfn_limit (ie. not mapping the Launcher binary).
*/
check_gpte(cpu, gpte);
if (!check_gpte(cpu, gpte))
return false;
/* Add the _PAGE_ACCESSED and (for a write) _PAGE_DIRTY flag */
gpte = pte_mkyoung(gpte);
......@@ -441,7 +472,9 @@ bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
gpte = pte_mkdirty(gpte);
/* Get the pointer to the shadow PTE entry we're going to set. */
spte = spte_addr(cpu, *spgd, vaddr);
spte = find_spte(cpu, vaddr, true, pgd_flags(gpgd), pmd_flags(gpmd));
if (!spte)
return false;
/*
* If there was a valid shadow PTE entry here before, we release it.
......@@ -493,29 +526,23 @@ bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
*/
static bool page_writable(struct lg_cpu *cpu, unsigned long vaddr)
{
pgd_t *spgd;
pte_t *spte;
unsigned long flags;
#ifdef CONFIG_X86_PAE
pmd_t *spmd;
#endif
/* Look at the current top level entry: is it present? */
spgd = spgd_addr(cpu, cpu->cpu_pgd, vaddr);
if (!(pgd_flags(*spgd) & _PAGE_PRESENT))
/* You can't put your stack in the Switcher! */
if (vaddr >= switcher_addr)
return false;
#ifdef CONFIG_X86_PAE
spmd = spmd_addr(cpu, *spgd, vaddr);
if (!(pmd_flags(*spmd) & _PAGE_PRESENT))
/* If there's no shadow PTE, it's not writable. */
spte = find_spte(cpu, vaddr, false, 0, 0);
if (!spte)
return false;
#endif
/*
* Check the flags on the pte entry itself: it must be present and
* writable.
*/
flags = pte_flags(*(spte_addr(cpu, *spgd, vaddr)));
flags = pte_flags(*spte);
return (flags & (_PAGE_PRESENT|_PAGE_RW)) == (_PAGE_PRESENT|_PAGE_RW);
}
......@@ -678,9 +705,6 @@ static unsigned int new_pgdir(struct lg_cpu *cpu,
int *blank_pgdir)
{
unsigned int next;
#ifdef CONFIG_X86_PAE
pmd_t *pmd_table;
#endif
/*
* We pick one entry at random to throw out. Choosing the Least
......@@ -695,29 +719,11 @@ static unsigned int new_pgdir(struct lg_cpu *cpu,
if (!cpu->lg->pgdirs[next].pgdir)
next = cpu->cpu_pgd;
else {
#ifdef CONFIG_X86_PAE
/*
* In PAE mode, allocate a pmd page and populate the
* last pgd entry.
* This is a blank page, so there are no kernel
* mappings: caller must map the stack!
*/
pmd_table = (pmd_t *)get_zeroed_page(GFP_KERNEL);
if (!pmd_table) {
free_page((long)cpu->lg->pgdirs[next].pgdir);
set_pgd(cpu->lg->pgdirs[next].pgdir, __pgd(0));
next = cpu->cpu_pgd;
} else {
set_pgd(cpu->lg->pgdirs[next].pgdir +
SWITCHER_PGD_INDEX,
__pgd(__pa(pmd_table) | _PAGE_PRESENT));
/*
* This is a blank page, so there are no kernel
* mappings: caller must map the stack!
*/
*blank_pgdir = 1;
}
#else
*blank_pgdir = 1;
#endif
}
}
/* Record which Guest toplevel this shadows. */
......@@ -725,9 +731,50 @@ static unsigned int new_pgdir(struct lg_cpu *cpu,
/* Release all the non-kernel mappings. */
flush_user_mappings(cpu->lg, next);
/* This hasn't run on any CPU at all. */
cpu->lg->pgdirs[next].last_host_cpu = -1;
return next;
}
/*H:501
* We do need the Switcher code mapped at all times, so we allocate that
* part of the Guest page table here. We map the Switcher code immediately,
* but defer mapping of the guest register page and IDT/LDT etc page until
* just before we run the guest in map_switcher_in_guest().
*
* We *could* do this setup in map_switcher_in_guest(), but at that point
* we've interrupts disabled, and allocating pages like that is fraught: we
* can't sleep if we need to free up some memory.
*/
static bool allocate_switcher_mapping(struct lg_cpu *cpu)
{
int i;
for (i = 0; i < TOTAL_SWITCHER_PAGES; i++) {
pte_t *pte = find_spte(cpu, switcher_addr + i * PAGE_SIZE, true,
CHECK_GPGD_MASK, _PAGE_TABLE);
if (!pte)
return false;
/*
* Map the switcher page if not already there. It might
* already be there because we call allocate_switcher_mapping()
* in guest_set_pgd() just in case it did discard our Switcher
* mapping, but it probably didn't.
*/
if (i == 0 && !(pte_flags(*pte) & _PAGE_PRESENT)) {
/* Get a reference to the Switcher page. */
get_page(lg_switcher_pages[0]);
/* Create a read-only, exectuable, kernel-style PTE */
set_pte(pte,
mk_pte(lg_switcher_pages[0], PAGE_KERNEL_RX));
}
}
cpu->lg->pgdirs[cpu->cpu_pgd].switcher_mapped = true;
return true;
}
/*H:470
* Finally, a routine which throws away everything: all PGD entries in all
* the shadow page tables, including the Guest's kernel mappings. This is used
......@@ -738,28 +785,16 @@ static void release_all_pagetables(struct lguest *lg)
unsigned int i, j;
/* Every shadow pagetable this Guest has */
for (i = 0; i < ARRAY_SIZE(lg->pgdirs); i++)
if (lg->pgdirs[i].pgdir) {
#ifdef CONFIG_X86_PAE
pgd_t *spgd;
pmd_t *pmdpage;
unsigned int k;
/* Get the last pmd page. */
spgd = lg->pgdirs[i].pgdir + SWITCHER_PGD_INDEX;
pmdpage = __va(pgd_pfn(*spgd) << PAGE_SHIFT);
/*
* And release the pmd entries of that pmd page,
* except for the switcher pmd.
*/
for (k = 0; k < SWITCHER_PMD_INDEX; k++)
release_pmd(&pmdpage[k]);
#endif
/* Every PGD entry except the Switcher at the top */
for (j = 0; j < SWITCHER_PGD_INDEX; j++)
release_pgd(lg->pgdirs[i].pgdir + j);
}
for (i = 0; i < ARRAY_SIZE(lg->pgdirs); i++) {
if (!lg->pgdirs[i].pgdir)
continue;
/* Every PGD entry. */
for (j = 0; j < PTRS_PER_PGD; j++)
release_pgd(lg->pgdirs[i].pgdir + j);
lg->pgdirs[i].switcher_mapped = false;
lg->pgdirs[i].last_host_cpu = -1;
}
}
/*
......@@ -773,6 +808,9 @@ void guest_pagetable_clear_all(struct lg_cpu *cpu)
release_all_pagetables(cpu->lg);
/* We need the Guest kernel stack mapped again. */
pin_stack_pages(cpu);
/* And we need Switcher allocated. */
if (!allocate_switcher_mapping(cpu))
kill_guest(cpu, "Cannot populate switcher mapping");
}
/*H:430
......@@ -808,9 +846,17 @@ void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable)
newpgdir = new_pgdir(cpu, pgtable, &repin);
/* Change the current pgd index to the new one. */
cpu->cpu_pgd = newpgdir;
/* If it was completely blank, we map in the Guest kernel stack */
/*
* If it was completely blank, we map in the Guest kernel stack and
* the Switcher.
*/
if (repin)
pin_stack_pages(cpu);
if (!cpu->lg->pgdirs[cpu->cpu_pgd].switcher_mapped) {
if (!allocate_switcher_mapping(cpu))
kill_guest(cpu, "Cannot populate switcher mapping");
}
}
/*:*/
......@@ -865,7 +911,8 @@ static void do_set_pte(struct lg_cpu *cpu, int idx,
* micro-benchmark.
*/
if (pte_flags(gpte) & (_PAGE_DIRTY | _PAGE_ACCESSED)) {
check_gpte(cpu, gpte);
if (!check_gpte(cpu, gpte))
return;
set_pte(spte,
gpte_to_spte(cpu, gpte,
pte_flags(gpte) & _PAGE_DIRTY));
......@@ -897,6 +944,12 @@ static void do_set_pte(struct lg_cpu *cpu, int idx,
void guest_set_pte(struct lg_cpu *cpu,
unsigned long gpgdir, unsigned long vaddr, pte_t gpte)
{
/* We don't let you remap the Switcher; we need it to get back! */
if (vaddr >= switcher_addr) {
kill_guest(cpu, "attempt to set pte into Switcher pages");
return;
}
/*
* Kernel mappings must be changed on all top levels. Slow, but doesn't
* happen often.
......@@ -933,14 +986,23 @@ void guest_set_pgd(struct lguest *lg, unsigned long gpgdir, u32 idx)
{
int pgdir;
if (idx >= SWITCHER_PGD_INDEX)
if (idx > PTRS_PER_PGD) {
kill_guest(&lg->cpus[0], "Attempt to set pgd %u/%u",
idx, PTRS_PER_PGD);
return;
}
/* If they're talking about a page table we have a shadow for... */
pgdir = find_pgdir(lg, gpgdir);
if (pgdir < ARRAY_SIZE(lg->pgdirs))
if (pgdir < ARRAY_SIZE(lg->pgdirs)) {
/* ... throw it away. */
release_pgd(lg->pgdirs[pgdir].pgdir + idx);
/* That might have been the Switcher mapping, remap it. */
if (!allocate_switcher_mapping(&lg->cpus[0])) {
kill_guest(&lg->cpus[0],
"Cannot populate switcher mapping");
}
}
}
#ifdef CONFIG_X86_PAE
......@@ -958,6 +1020,9 @@ void guest_set_pmd(struct lguest *lg, unsigned long pmdp, u32 idx)
* we will populate on future faults. The Guest doesn't have any actual
* pagetables yet, so we set linear_pages to tell demand_page() to fake it
* for the moment.
*
* We do need the Switcher to be mapped at all times, so we allocate that
* part of the Guest page table here.
*/
int init_guest_pagetable(struct lguest *lg)
{
......@@ -971,21 +1036,34 @@ int init_guest_pagetable(struct lguest *lg)
/* We start with a linear mapping until the initialize. */
cpu->linear_pages = true;
/* Allocate the page tables for the Switcher. */
if (!allocate_switcher_mapping(cpu)) {
release_all_pagetables(lg);
return -ENOMEM;
}
return 0;
}
/*H:508 When the Guest calls LHCALL_LGUEST_INIT we do more setup. */
void page_table_guest_data_init(struct lg_cpu *cpu)
{
/*
* We tell the Guest that it can't use the virtual addresses
* used by the Switcher. This trick is equivalent to 4GB -
* switcher_addr.
*/
u32 top = ~switcher_addr + 1;
/* We get the kernel address: above this is all kernel memory. */
if (get_user(cpu->lg->kernel_address,
&cpu->lg->lguest_data->kernel_address)
&cpu->lg->lguest_data->kernel_address)
/*
* We tell the Guest that it can't use the top 2 or 4 MB
* of virtual addresses used by the Switcher.
* We tell the Guest that it can't use the top virtual
* addresses (used by the Switcher).
*/
|| put_user(RESERVE_MEM * 1024 * 1024,
&cpu->lg->lguest_data->reserve_mem)) {
|| put_user(top, &cpu->lg->lguest_data->reserve_mem)) {
kill_guest(cpu, "bad guest page %p", cpu->lg->lguest_data);
return;
}
......@@ -995,12 +1073,7 @@ void page_table_guest_data_init(struct lg_cpu *cpu)
* "pgd_index(lg->kernel_address)". This assumes it won't hit the
* Switcher mappings, so check that now.
*/
#ifdef CONFIG_X86_PAE
if (pgd_index(cpu->lg->kernel_address) == SWITCHER_PGD_INDEX &&
pmd_index(cpu->lg->kernel_address) == SWITCHER_PMD_INDEX)
#else
if (pgd_index(cpu->lg->kernel_address) >= SWITCHER_PGD_INDEX)
#endif
if (cpu->lg->kernel_address >= switcher_addr)
kill_guest(cpu, "bad kernel address %#lx",
cpu->lg->kernel_address);
}
......@@ -1017,102 +1090,96 @@ void free_guest_pagetable(struct lguest *lg)
free_page((long)lg->pgdirs[i].pgdir);
}
/*H:480
* (vi) Mapping the Switcher when the Guest is about to run.
*
* The Switcher and the two pages for this CPU need to be visible in the
* Guest (and not the pages for other CPUs). We have the appropriate PTE pages
* for each CPU already set up, we just need to hook them in now we know which
* Guest is about to run on this CPU.
/*H:481
* This clears the Switcher mappings for cpu #i.
*/
void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages)
static void remove_switcher_percpu_map(struct lg_cpu *cpu, unsigned int i)
{
pte_t *switcher_pte_page = __this_cpu_read(switcher_pte_pages);
pte_t regs_pte;
unsigned long base = switcher_addr + PAGE_SIZE + i * PAGE_SIZE*2;
pte_t *pte;
#ifdef CONFIG_X86_PAE
pmd_t switcher_pmd;
pmd_t *pmd_table;
switcher_pmd = pfn_pmd(__pa(switcher_pte_page) >> PAGE_SHIFT,
PAGE_KERNEL_EXEC);
/* Figure out where the pmd page is, by reading the PGD, and converting
* it to a virtual address. */
pmd_table = __va(pgd_pfn(cpu->lg->
pgdirs[cpu->cpu_pgd].pgdir[SWITCHER_PGD_INDEX])
<< PAGE_SHIFT);
/* Now write it into the shadow page table. */
set_pmd(&pmd_table[SWITCHER_PMD_INDEX], switcher_pmd);
#else
pgd_t switcher_pgd;
/* Clear the mappings for both pages. */
pte = find_spte(cpu, base, false, 0, 0);
release_pte(*pte);
set_pte(pte, __pte(0));
/*
* Make the last PGD entry for this Guest point to the Switcher's PTE
* page for this CPU (with appropriate flags).
*/
switcher_pgd = __pgd(__pa(switcher_pte_page) | __PAGE_KERNEL_EXEC);
cpu->lg->pgdirs[cpu->cpu_pgd].pgdir[SWITCHER_PGD_INDEX] = switcher_pgd;
#endif
/*
* We also change the Switcher PTE page. When we're running the Guest,
* we want the Guest's "regs" page to appear where the first Switcher
* page for this CPU is. This is an optimization: when the Switcher
* saves the Guest registers, it saves them into the first page of this
* CPU's "struct lguest_pages": if we make sure the Guest's register
* page is already mapped there, we don't have to copy them out
* again.
*/
regs_pte = pfn_pte(__pa(cpu->regs_page) >> PAGE_SHIFT, PAGE_KERNEL);
set_pte(&switcher_pte_page[pte_index((unsigned long)pages)], regs_pte);
pte = find_spte(cpu, base + PAGE_SIZE, false, 0, 0);
release_pte(*pte);
set_pte(pte, __pte(0));
}
/*:*/
static void free_switcher_pte_pages(void)
{
unsigned int i;
for_each_possible_cpu(i)
free_page((long)switcher_pte_page(i));
}
/*H:520
* Setting up the Switcher PTE page for given CPU is fairly easy, given
* the CPU number and the "struct page"s for the Switcher code itself.
/*H:480
* (vi) Mapping the Switcher when the Guest is about to run.
*
* The Switcher and the two pages for this CPU need to be visible in the Guest
* (and not the pages for other CPUs).
*
* Currently the Switcher is less than a page long, so "pages" is always 1.
* The pages for the pagetables have all been allocated before: we just need
* to make sure the actual PTEs are up-to-date for the CPU we're about to run
* on.
*/
static __init void populate_switcher_pte_page(unsigned int cpu,
struct page *switcher_page[],
unsigned int pages)
void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages)
{
unsigned int i;
pte_t *pte = switcher_pte_page(cpu);
unsigned long base;
struct page *percpu_switcher_page, *regs_page;
pte_t *pte;
struct pgdir *pgdir = &cpu->lg->pgdirs[cpu->cpu_pgd];
/* Switcher page should always be mapped by now! */
BUG_ON(!pgdir->switcher_mapped);
/*
* Remember that we have two pages for each Host CPU, so we can run a
* Guest on each CPU without them interfering. We need to make sure
* those pages are mapped correctly in the Guest, but since we usually
* run on the same CPU, we cache that, and only update the mappings
* when we move.
*/
if (pgdir->last_host_cpu == raw_smp_processor_id())
return;
/* The first entries are easy: they map the Switcher code. */
for (i = 0; i < pages; i++) {
set_pte(&pte[i], mk_pte(switcher_page[i],
__pgprot(_PAGE_PRESENT|_PAGE_ACCESSED)));
/* -1 means unknown so we remove everything. */
if (pgdir->last_host_cpu == -1) {
unsigned int i;
for_each_possible_cpu(i)
remove_switcher_percpu_map(cpu, i);
} else {
/* We know exactly what CPU mapping to remove. */
remove_switcher_percpu_map(cpu, pgdir->last_host_cpu);
}
/* The only other thing we map is this CPU's pair of pages. */
i = pages + cpu*2;
/* First page (Guest registers) is writable from the Guest */
set_pte(&pte[i], pfn_pte(page_to_pfn(switcher_page[i]),
__pgprot(_PAGE_PRESENT|_PAGE_ACCESSED|_PAGE_RW)));
/*
* When we're running the Guest, we want the Guest's "regs" page to
* appear where the first Switcher page for this CPU is. This is an
* optimization: when the Switcher saves the Guest registers, it saves
* them into the first page of this CPU's "struct lguest_pages": if we
* make sure the Guest's register page is already mapped there, we
* don't have to copy them out again.
*/
/* Find the shadow PTE for this regs page. */
base = switcher_addr + PAGE_SIZE
+ raw_smp_processor_id() * sizeof(struct lguest_pages);
pte = find_spte(cpu, base, false, 0, 0);
regs_page = pfn_to_page(__pa(cpu->regs_page) >> PAGE_SHIFT);
get_page(regs_page);
set_pte(pte, mk_pte(regs_page, __pgprot(__PAGE_KERNEL & ~_PAGE_GLOBAL)));
/*
* The second page contains the "struct lguest_ro_state", and is
* read-only.
* We map the second page of the struct lguest_pages read-only in
* the Guest: the IDT, GDT and other things it's not supposed to
* change.
*/
set_pte(&pte[i+1], pfn_pte(page_to_pfn(switcher_page[i+1]),
__pgprot(_PAGE_PRESENT|_PAGE_ACCESSED)));
pte = find_spte(cpu, base + PAGE_SIZE, false, 0, 0);
percpu_switcher_page
= lg_switcher_pages[1 + raw_smp_processor_id()*2 + 1];
get_page(percpu_switcher_page);
set_pte(pte, mk_pte(percpu_switcher_page,
__pgprot(__PAGE_KERNEL_RO & ~_PAGE_GLOBAL)));
pgdir->last_host_cpu = raw_smp_processor_id();
}
/*
/*H:490
* We've made it through the page table code. Perhaps our tired brains are
* still processing the details, or perhaps we're simply glad it's over.
*
......@@ -1124,29 +1191,3 @@ static __init void populate_switcher_pte_page(unsigned int cpu,
*
* There is just one file remaining in the Host.
*/
/*H:510
* At boot or module load time, init_pagetables() allocates and populates
* the Switcher PTE page for each CPU.
*/
__init int init_pagetables(struct page **switcher_page, unsigned int pages)
{
unsigned int i;
for_each_possible_cpu(i) {
switcher_pte_page(i) = (pte_t *)get_zeroed_page(GFP_KERNEL);
if (!switcher_pte_page(i)) {
free_switcher_pte_pages();
return -ENOMEM;
}
populate_switcher_pte_page(i, switcher_page, pages);
}
return 0;
}
/*:*/
/* Cleaning up simply involves freeing the PTE page for each CPU. */
void free_pagetables(void)
{
free_switcher_pte_pages();
}
drivers/lguest/x86/core.c
View file @ 736a2dd2
......@@ -59,14 +59,13 @@ static struct {
/* Offset from where switcher.S was compiled to where we've copied it */
static unsigned long switcher_offset(void)
{
return SWITCHER_ADDR - (unsigned long)start_switcher_text;
return switcher_addr - (unsigned long)start_switcher_text;
}
/* This cpu's struct lguest_pages. */
/* This cpu's struct lguest_pages (after the Switcher text page) */
static struct lguest_pages *lguest_pages(unsigned int cpu)
{
return &(((struct lguest_pages *)
(SWITCHER_ADDR + SHARED_SWITCHER_PAGES*PAGE_SIZE))[cpu]);
return &(((struct lguest_pages *)(switcher_addr + PAGE_SIZE))[cpu]);
}
static DEFINE_PER_CPU(struct lg_cpu *, lg_last_cpu);
......
drivers/net/caif/Kconfig
View file @ 736a2dd2
......@@ -40,3 +40,17 @@ config CAIF_HSI
The caif low level driver for CAIF over HSI.
Be aware that if you enable this then you also need to
enable a low-level HSI driver.
config CAIF_VIRTIO
tristate "CAIF virtio transport driver"
depends on CAIF
select VHOST_RING
select VIRTIO
select GENERIC_ALLOCATOR
default n
---help---
The caif driver for CAIF over Virtio.
if CAIF_VIRTIO
source "drivers/vhost/Kconfig"
endif
drivers/net/caif/Makefile
View file @ 736a2dd2
......@@ -9,3 +9,6 @@ obj-$(CONFIG_CAIF_SPI_SLAVE) += cfspi_slave.o
# HSI interface
obj-$(CONFIG_CAIF_HSI) += caif_hsi.o
# Virtio interface
obj-$(CONFIG_CAIF_VIRTIO) += caif_virtio.o
drivers/net/caif/caif_virtio.c 0 → 100644
View file @ 736a2dd2
/*
* Copyright (C) ST-Ericsson AB 2013
* Authors: Vicram Arv
* Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
* Sjur Brendeland
* License terms: GNU General Public License (GPL) version 2
*/
#include <linux/module.h>
#include <linux/if_arp.h>
#include <linux/virtio.h>
#include <linux/vringh.h>
#include <linux/debugfs.h>
#include <linux/spinlock.h>
#include <linux/genalloc.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/virtio_ids.h>
#include <linux/virtio_caif.h>
#include <linux/virtio_ring.h>
#include <linux/dma-mapping.h>
#include <net/caif/caif_dev.h>
#include <linux/virtio_config.h>
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Vicram Arv");
MODULE_AUTHOR("Sjur Brendeland");
MODULE_DESCRIPTION("Virtio CAIF Driver");
/* NAPI schedule quota */
#define CFV_DEFAULT_QUOTA 32
/* Defaults used if virtio config space is unavailable */
#define CFV_DEF_MTU_SIZE 4096
#define CFV_DEF_HEADROOM 32
#define CFV_DEF_TAILROOM 32
/* Required IP header alignment */
#define IP_HDR_ALIGN 4
/* struct cfv_napi_contxt - NAPI context info
* @riov: IOV holding data read from the ring. Note that riov may
* still hold data when cfv_rx_poll() returns.
* @head: Last descriptor ID we received from vringh_getdesc_kern.
* We use this to put descriptor back on the used ring. USHRT_MAX is
* used to indicate invalid head-id.
*/
struct cfv_napi_context {
struct vringh_kiov riov;
unsigned short head;
};
/* struct cfv_stats - statistics for debugfs
* @rx_napi_complete: Number of NAPI completions (RX)
* @rx_napi_resched: Number of calls where the full quota was used (RX)
* @rx_nomem: Number of SKB alloc failures (RX)
* @rx_kicks: Number of RX kicks
* @tx_full_ring: Number times TX ring was full
* @tx_no_mem: Number of times TX went out of memory
* @tx_flow_on: Number of flow on (TX)
* @tx_kicks: Number of TX kicks
*/
struct cfv_stats {
u32 rx_napi_complete;
u32 rx_napi_resched;
u32 rx_nomem;
u32 rx_kicks;
u32 tx_full_ring;
u32 tx_no_mem;
u32 tx_flow_on;
u32 tx_kicks;
};
/* struct cfv_info - Caif Virtio control structure
* @cfdev: caif common header
* @vdev: Associated virtio device
* @vr_rx: rx/downlink host vring
* @vq_tx: tx/uplink virtqueue
* @ndev: CAIF link layer device
* @watermark_tx: indicates number of free descriptors we need
* to reopen the tx-queues after overload.
* @tx_lock: protects vq_tx from concurrent use
* @tx_release_tasklet: Tasklet for freeing consumed TX buffers
* @napi: Napi context used in cfv_rx_poll()
* @ctx: Context data used in cfv_rx_poll()
* @tx_hr: transmit headroom
* @rx_hr: receive headroom
* @tx_tr: transmit tail room
* @rx_tr: receive tail room
* @mtu: transmit max size
* @mru: receive max size
* @allocsz: size of dma memory reserved for TX buffers
* @alloc_addr: virtual address to dma memory for TX buffers
* @alloc_dma: dma address to dma memory for TX buffers
* @genpool: Gen Pool used for allocating TX buffers
* @reserved_mem: Pointer to memory reserve allocated from genpool
* @reserved_size: Size of memory reserve allocated from genpool
* @stats: Statistics exposed in sysfs
* @debugfs: Debugfs dentry for statistic counters
*/
struct cfv_info {
struct caif_dev_common cfdev;
struct virtio_device *vdev;
struct vringh *vr_rx;
struct virtqueue *vq_tx;
struct net_device *ndev;
unsigned int watermark_tx;
/* Protect access to vq_tx */
spinlock_t tx_lock;
struct tasklet_struct tx_release_tasklet;
struct napi_struct napi;
struct cfv_napi_context ctx;
u16 tx_hr;
u16 rx_hr;
u16 tx_tr;
u16 rx_tr;
u32 mtu;
u32 mru;
size_t allocsz;
void *alloc_addr;
dma_addr_t alloc_dma;
struct gen_pool *genpool;
unsigned long reserved_mem;
size_t reserved_size;
struct cfv_stats stats;
struct dentry *debugfs;
};
/* struct buf_info - maintains transmit buffer data handle
* @size: size of transmit buffer
* @dma_handle: handle to allocated dma device memory area
* @vaddr: virtual address mapping to allocated memory area
*/
struct buf_info {
size_t size;
u8 *vaddr;
};
/* Called from virtio device, in IRQ context */
static void cfv_release_cb(struct virtqueue *vq_tx)
{
struct cfv_info *cfv = vq_tx->vdev->priv;
++cfv->stats.tx_kicks;
tasklet_schedule(&cfv->tx_release_tasklet);
}
static void free_buf_info(struct cfv_info *cfv, struct buf_info *buf_info)
{
if (!buf_info)
return;
gen_pool_free(cfv->genpool, (unsigned long) buf_info->vaddr,
buf_info->size);
kfree(buf_info);
}
/* This is invoked whenever the remote processor completed processing
* a TX msg we just sent, and the buffer is put back to the used ring.
*/
static void cfv_release_used_buf(struct virtqueue *vq_tx)
{
struct cfv_info *cfv = vq_tx->vdev->priv;
unsigned long flags;
BUG_ON(vq_tx != cfv->vq_tx);
for (;;) {
unsigned int len;
struct buf_info *buf_info;
/* Get used buffer from used ring to recycle used descriptors */
spin_lock_irqsave(&cfv->tx_lock, flags);
buf_info = virtqueue_get_buf(vq_tx, &len);
spin_unlock_irqrestore(&cfv->tx_lock, flags);
/* Stop looping if there are no more buffers to free */
if (!buf_info)
break;
free_buf_info(cfv, buf_info);
/* watermark_tx indicates if we previously stopped the tx
* queues. If we have enough free stots in the virtio ring,
* re-establish memory reserved and open up tx queues.
*/
if (cfv->vq_tx->num_free <= cfv->watermark_tx)
continue;
/* Re-establish memory reserve */
if (cfv->reserved_mem == 0 && cfv->genpool)
cfv->reserved_mem =
gen_pool_alloc(cfv->genpool,
cfv->reserved_size);
/* Open up the tx queues */
if (cfv->reserved_mem) {
cfv->watermark_tx =
virtqueue_get_vring_size(cfv->vq_tx);
netif_tx_wake_all_queues(cfv->ndev);
/* Buffers are recycled in cfv_netdev_tx, so
* disable notifications when queues are opened.
*/
virtqueue_disable_cb(cfv->vq_tx);
++cfv->stats.tx_flow_on;
} else {
/* if no memory reserve, wait for more free slots */
WARN_ON(cfv->watermark_tx >
virtqueue_get_vring_size(cfv->vq_tx));
cfv->watermark_tx +=
virtqueue_get_vring_size(cfv->vq_tx) / 4;
}
}
}
/* Allocate a SKB and copy packet data to it */
static struct sk_buff *cfv_alloc_and_copy_skb(int *err,
struct cfv_info *cfv,
u8 *frm, u32 frm_len)
{
struct sk_buff *skb;
u32 cfpkt_len, pad_len;
*err = 0;
/* Verify that packet size with down-link header and mtu size */
if (frm_len > cfv->mru || frm_len <= cfv->rx_hr + cfv->rx_tr) {
netdev_err(cfv->ndev,
"Invalid frmlen:%u mtu:%u hr:%d tr:%d\n",
frm_len, cfv->mru, cfv->rx_hr,
cfv->rx_tr);
*err = -EPROTO;
return NULL;
}
cfpkt_len = frm_len - (cfv->rx_hr + cfv->rx_tr);
pad_len = (unsigned long)(frm + cfv->rx_hr) & (IP_HDR_ALIGN - 1);
skb = netdev_alloc_skb(cfv->ndev, frm_len + pad_len);
if (!skb) {
*err = -ENOMEM;
return NULL;
}
skb_reserve(skb, cfv->rx_hr + pad_len);
memcpy(skb_put(skb, cfpkt_len), frm + cfv->rx_hr, cfpkt_len);
return skb;
}
/* Get packets from the host vring */
static int cfv_rx_poll(struct napi_struct *napi, int quota)
{
struct cfv_info *cfv = container_of(napi, struct cfv_info, napi);
int rxcnt = 0;
int err = 0;
void *buf;
struct sk_buff *skb;
struct vringh_kiov *riov = &cfv->ctx.riov;
unsigned int skb_len;
again:
do {
skb = NULL;
/* Put the previous iovec back on the used ring and
* fetch a new iovec if we have processed all elements.
*/
if (riov->i == riov->used) {
if (cfv->ctx.head != USHRT_MAX) {
vringh_complete_kern(cfv->vr_rx,
cfv->ctx.head,
0);
cfv->ctx.head = USHRT_MAX;
}
err = vringh_getdesc_kern(
cfv->vr_rx,
riov,
NULL,
&cfv->ctx.head,
GFP_ATOMIC);
if (err <= 0)
goto exit;
}
buf = phys_to_virt((unsigned long) riov->iov[riov->i].iov_base);
/* TODO: Add check on valid buffer address */
skb = cfv_alloc_and_copy_skb(&err, cfv, buf,
riov->iov[riov->i].iov_len);
if (unlikely(err))
goto exit;
/* Push received packet up the stack. */
skb_len = skb->len;
skb->protocol = htons(ETH_P_CAIF);
skb_reset_mac_header(skb);
skb->dev = cfv->ndev;
err = netif_receive_skb(skb);
if (unlikely(err)) {
++cfv->ndev->stats.rx_dropped;
} else {
++cfv->ndev->stats.rx_packets;
cfv->ndev->stats.rx_bytes += skb_len;
}
++riov->i;
++rxcnt;
} while (rxcnt < quota);
++cfv->stats.rx_napi_resched;
goto out;
exit:
switch (err) {
case 0:
++cfv->stats.rx_napi_complete;
/* Really out of patckets? (stolen from virtio_net)*/
napi_complete(napi);
if (unlikely(!vringh_notify_enable_kern(cfv->vr_rx)) &&
napi_schedule_prep(napi)) {
vringh_notify_disable_kern(cfv->vr_rx);
__napi_schedule(napi);
goto again;
}
break;
case -ENOMEM:
++cfv->stats.rx_nomem;
dev_kfree_skb(skb);
/* Stop NAPI poll on OOM, we hope to be polled later */
napi_complete(napi);
vringh_notify_enable_kern(cfv->vr_rx);
break;
default:
/* We're doomed, any modem fault is fatal */
netdev_warn(cfv->ndev, "Bad ring, disable device\n");
cfv->ndev->stats.rx_dropped = riov->used - riov->i;
napi_complete(napi);
vringh_notify_disable_kern(cfv->vr_rx);
netif_carrier_off(cfv->ndev);
break;
}
out:
if (rxcnt && vringh_need_notify_kern(cfv->vr_rx) > 0)
vringh_notify(cfv->vr_rx);
return rxcnt;
}
static void cfv_recv(struct virtio_device *vdev, struct vringh *vr_rx)
{
struct cfv_info *cfv = vdev->priv;
++cfv->stats.rx_kicks;
vringh_notify_disable_kern(cfv->vr_rx);
napi_schedule(&cfv->napi);
}
static void cfv_destroy_genpool(struct cfv_info *cfv)
{
if (cfv->alloc_addr)
dma_free_coherent(cfv->vdev->dev.parent->parent,
cfv->allocsz, cfv->alloc_addr,
cfv->alloc_dma);
if (!cfv->genpool)
return;
gen_pool_free(cfv->genpool, cfv->reserved_mem,
cfv->reserved_size);
gen_pool_destroy(cfv->genpool);
cfv->genpool = NULL;
}
static int cfv_create_genpool(struct cfv_info *cfv)
{
int err;
/* dma_alloc can only allocate whole pages, and we need a more
* fine graned allocation so we use genpool. We ask for space needed
* by IP and a full ring. If the dma allcoation fails we retry with a
* smaller allocation size.
*/
err = -ENOMEM;
cfv->allocsz = (virtqueue_get_vring_size(cfv->vq_tx) *
(ETH_DATA_LEN + cfv->tx_hr + cfv->tx_tr) * 11)/10;
if (cfv->allocsz <= (num_possible_cpus() + 1) * cfv->ndev->mtu)
return -EINVAL;
for (;;) {
if (cfv->allocsz <= num_possible_cpus() * cfv->ndev->mtu) {
netdev_info(cfv->ndev, "Not enough device memory\n");
return -ENOMEM;
}
cfv->alloc_addr = dma_alloc_coherent(
cfv->vdev->dev.parent->parent,
cfv->allocsz, &cfv->alloc_dma,
GFP_ATOMIC);
if (cfv->alloc_addr)
break;
cfv->allocsz = (cfv->allocsz * 3) >> 2;
}
netdev_dbg(cfv->ndev, "Allocated %zd bytes from dma-memory\n",
cfv->allocsz);
/* Allocate on 128 bytes boundaries (1 << 7)*/
cfv->genpool = gen_pool_create(7, -1);
if (!cfv->genpool)
goto err;
err = gen_pool_add_virt(cfv->genpool, (unsigned long)cfv->alloc_addr,
(phys_addr_t)virt_to_phys(cfv->alloc_addr),
cfv->allocsz, -1);
if (err)
goto err;
/* Reserve some memory for low memory situations. If we hit the roof
* in the memory pool, we stop TX flow and release the reserve.
*/
cfv->reserved_size = num_possible_cpus() * cfv->ndev->mtu;
cfv->reserved_mem = gen_pool_alloc(cfv->genpool,
cfv->reserved_size);
if (!cfv->reserved_mem) {
err = -ENOMEM;
goto err;
}
cfv->watermark_tx = virtqueue_get_vring_size(cfv->vq_tx);
return 0;
err:
cfv_destroy_genpool(cfv);
return err;
}
/* Enable the CAIF interface and allocate the memory-pool */
static int cfv_netdev_open(struct net_device *netdev)
{
struct cfv_info *cfv = netdev_priv(netdev);
if (cfv_create_genpool(cfv))
return -ENOMEM;
netif_carrier_on(netdev);
napi_enable(&cfv->napi);
/* Schedule NAPI to read any pending packets */
napi_schedule(&cfv->napi);
return 0;
}
/* Disable the CAIF interface and free the memory-pool */
static int cfv_netdev_close(struct net_device *netdev)
{
struct cfv_info *cfv = netdev_priv(netdev);
unsigned long flags;
struct buf_info *buf_info;
/* Disable interrupts, queues and NAPI polling */
netif_carrier_off(netdev);
virtqueue_disable_cb(cfv->vq_tx);
vringh_notify_disable_kern(cfv->vr_rx);
napi_disable(&cfv->napi);
/* Release any TX buffers on both used and avilable rings */
cfv_release_used_buf(cfv->vq_tx);
spin_lock_irqsave(&cfv->tx_lock, flags);
while ((buf_info = virtqueue_detach_unused_buf(cfv->vq_tx)))
free_buf_info(cfv, buf_info);
spin_unlock_irqrestore(&cfv->tx_lock, flags);
/* Release all dma allocated memory and destroy the pool */
cfv_destroy_genpool(cfv);
return 0;
}
/* Allocate a buffer in dma-memory and copy skb to it */
static struct buf_info *cfv_alloc_and_copy_to_shm(struct cfv_info *cfv,
struct sk_buff *skb,
struct scatterlist *sg)
{
struct caif_payload_info *info = (void *)&skb->cb;
struct buf_info *buf_info = NULL;
u8 pad_len, hdr_ofs;
if (!cfv->genpool)
goto err;
if (unlikely(cfv->tx_hr + skb->len + cfv->tx_tr > cfv->mtu)) {
netdev_warn(cfv->ndev, "Invalid packet len (%d > %d)\n",
cfv->tx_hr + skb->len + cfv->tx_tr, cfv->mtu);
goto err;
}
buf_info = kmalloc(sizeof(struct buf_info), GFP_ATOMIC);
if (unlikely(!buf_info))
goto err;
/* Make the IP header aligned in tbe buffer */
hdr_ofs = cfv->tx_hr + info->hdr_len;
pad_len = hdr_ofs & (IP_HDR_ALIGN - 1);
buf_info->size = cfv->tx_hr + skb->len + cfv->tx_tr + pad_len;
/* allocate dma memory buffer */
buf_info->vaddr = (void *)gen_pool_alloc(cfv->genpool, buf_info->size);
if (unlikely(!buf_info->vaddr))
goto err;
/* copy skbuf contents to send buffer */
skb_copy_bits(skb, 0, buf_info->vaddr + cfv->tx_hr + pad_len, skb->len);
sg_init_one(sg, buf_info->vaddr + pad_len,
skb->len + cfv->tx_hr + cfv->rx_hr);
return buf_info;
err:
kfree(buf_info);
return NULL;
}
/* Put the CAIF packet on the virtio ring and kick the receiver */
static int cfv_netdev_tx(struct sk_buff *skb, struct net_device *netdev)
{
struct cfv_info *cfv = netdev_priv(netdev);
struct buf_info *buf_info;
struct scatterlist sg;
unsigned long flags;
bool flow_off = false;
int ret;
/* garbage collect released buffers */
cfv_release_used_buf(cfv->vq_tx);
spin_lock_irqsave(&cfv->tx_lock, flags);
/* Flow-off check takes into account number of cpus to make sure
* virtqueue will not be overfilled in any possible smp conditions.
*
* Flow-on is triggered when sufficient buffers are freed
*/
if (unlikely(cfv->vq_tx->num_free <= num_present_cpus())) {
flow_off = true;
cfv->stats.tx_full_ring++;
}
/* If we run out of memory, we release the memory reserve and retry
* allocation.
*/
buf_info = cfv_alloc_and_copy_to_shm(cfv, skb, &sg);
if (unlikely(!buf_info)) {
cfv->stats.tx_no_mem++;
flow_off = true;
if (cfv->reserved_mem && cfv->genpool) {
gen_pool_free(cfv->genpool, cfv->reserved_mem,
cfv->reserved_size);
cfv->reserved_mem = 0;
buf_info = cfv_alloc_and_copy_to_shm(cfv, skb, &sg);
}
}
if (unlikely(flow_off)) {
/* Turn flow on when a 1/4 of the descriptors are released */
cfv->watermark_tx = virtqueue_get_vring_size(cfv->vq_tx) / 4;
/* Enable notifications of recycled TX buffers */
virtqueue_enable_cb(cfv->vq_tx);
netif_tx_stop_all_queues(netdev);
}
if (unlikely(!buf_info)) {
/* If the memory reserve does it's job, this shouldn't happen */
netdev_warn(cfv->ndev, "Out of gen_pool memory\n");
goto err;
}
ret = virtqueue_add_outbuf(cfv->vq_tx, &sg, 1, buf_info, GFP_ATOMIC);
if (unlikely((ret < 0))) {
/* If flow control works, this shouldn't happen */
netdev_warn(cfv->ndev, "Failed adding buffer to TX vring:%d\n",
ret);
goto err;
}
/* update netdev statistics */
cfv->ndev->stats.tx_packets++;
cfv->ndev->stats.tx_bytes += skb->len;
spin_unlock_irqrestore(&cfv->tx_lock, flags);
/* tell the remote processor it has a pending message to read */
virtqueue_kick(cfv->vq_tx);
dev_kfree_skb(skb);
return NETDEV_TX_OK;
err:
spin_unlock_irqrestore(&cfv->tx_lock, flags);
cfv->ndev->stats.tx_dropped++;
free_buf_info(cfv, buf_info);
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
static void cfv_tx_release_tasklet(unsigned long drv)
{
struct cfv_info *cfv = (struct cfv_info *)drv;
cfv_release_used_buf(cfv->vq_tx);
}
static const struct net_device_ops cfv_netdev_ops = {
.ndo_open = cfv_netdev_open,
.ndo_stop = cfv_netdev_close,
.ndo_start_xmit = cfv_netdev_tx,
};
static void cfv_netdev_setup(struct net_device *netdev)
{
netdev->netdev_ops = &cfv_netdev_ops;
netdev->type = ARPHRD_CAIF;
netdev->tx_queue_len = 100;
netdev->flags = IFF_POINTOPOINT | IFF_NOARP;
netdev->mtu = CFV_DEF_MTU_SIZE;
netdev->destructor = free_netdev;
}
/* Create debugfs counters for the device */
static inline void debugfs_init(struct cfv_info *cfv)
{
cfv->debugfs =
debugfs_create_dir(netdev_name(cfv->ndev), NULL);
if (IS_ERR(cfv->debugfs))
return;
debugfs_create_u32("rx-napi-complete", S_IRUSR, cfv->debugfs,
&cfv->stats.rx_napi_complete);
debugfs_create_u32("rx-napi-resched", S_IRUSR, cfv->debugfs,
&cfv->stats.rx_napi_resched);
debugfs_create_u32("rx-nomem", S_IRUSR, cfv->debugfs,
&cfv->stats.rx_nomem);
debugfs_create_u32("rx-kicks", S_IRUSR, cfv->debugfs,
&cfv->stats.rx_kicks);
debugfs_create_u32("tx-full-ring", S_IRUSR, cfv->debugfs,
&cfv->stats.tx_full_ring);
debugfs_create_u32("tx-no-mem", S_IRUSR, cfv->debugfs,
&cfv->stats.tx_no_mem);
debugfs_create_u32("tx-kicks", S_IRUSR, cfv->debugfs,
&cfv->stats.tx_kicks);
debugfs_create_u32("tx-flow-on", S_IRUSR, cfv->debugfs,
&cfv->stats.tx_flow_on);
}
/* Setup CAIF for the a virtio device */
static int cfv_probe(struct virtio_device *vdev)
{
vq_callback_t *vq_cbs = cfv_release_cb;
vrh_callback_t *vrh_cbs = cfv_recv;
const char *names = "output";
const char *cfv_netdev_name = "cfvrt";
struct net_device *netdev;
struct cfv_info *cfv;
int err = -EINVAL;
netdev = alloc_netdev(sizeof(struct cfv_info), cfv_netdev_name,
cfv_netdev_setup);
if (!netdev)
return -ENOMEM;
cfv = netdev_priv(netdev);
cfv->vdev = vdev;
cfv->ndev = netdev;
spin_lock_init(&cfv->tx_lock);
/* Get the RX virtio ring. This is a "host side vring". */
err = -ENODEV;
if (!vdev->vringh_config || !vdev->vringh_config->find_vrhs)
goto err;
err = vdev->vringh_config->find_vrhs(vdev, 1, &cfv->vr_rx, &vrh_cbs);
if (err)
goto err;
/* Get the TX virtio ring. This is a "guest side vring". */
err = vdev->config->find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs, &names);
if (err)
goto err;
/* Get the CAIF configuration from virtio config space, if available */
#define GET_VIRTIO_CONFIG_OPS(_v, _var, _f) \
((_v)->config->get(_v, offsetof(struct virtio_caif_transf_config, _f), \
&_var, \
FIELD_SIZEOF(struct virtio_caif_transf_config, _f)))
if (vdev->config->get) {
GET_VIRTIO_CONFIG_OPS(vdev, cfv->tx_hr, headroom);
GET_VIRTIO_CONFIG_OPS(vdev, cfv->rx_hr, headroom);
GET_VIRTIO_CONFIG_OPS(vdev, cfv->tx_tr, tailroom);
GET_VIRTIO_CONFIG_OPS(vdev, cfv->rx_tr, tailroom);
GET_VIRTIO_CONFIG_OPS(vdev, cfv->mtu, mtu);
GET_VIRTIO_CONFIG_OPS(vdev, cfv->mru, mtu);
} else {
cfv->tx_hr = CFV_DEF_HEADROOM;
cfv->rx_hr = CFV_DEF_HEADROOM;
cfv->tx_tr = CFV_DEF_TAILROOM;
cfv->rx_tr = CFV_DEF_TAILROOM;
cfv->mtu = CFV_DEF_MTU_SIZE;
cfv->mru = CFV_DEF_MTU_SIZE;
}
netdev->needed_headroom = cfv->tx_hr;
netdev->needed_tailroom = cfv->tx_tr;
/* Disable buffer release interrupts unless we have stopped TX queues */
virtqueue_disable_cb(cfv->vq_tx);
netdev->mtu = cfv->mtu - cfv->tx_tr;
vdev->priv = cfv;
/* Initialize NAPI poll context data */
vringh_kiov_init(&cfv->ctx.riov, NULL, 0);
cfv->ctx.head = USHRT_MAX;
netif_napi_add(netdev, &cfv->napi, cfv_rx_poll, CFV_DEFAULT_QUOTA);
tasklet_init(&cfv->tx_release_tasklet,
cfv_tx_release_tasklet,
(unsigned long)cfv);
/* Carrier is off until netdevice is opened */
netif_carrier_off(netdev);
/* register Netdev */
err = register_netdev(netdev);
if (err) {
dev_err(&vdev->dev, "Unable to register netdev (%d)\n", err);
goto err;
}
debugfs_init(cfv);
return 0;
err:
netdev_warn(cfv->ndev, "CAIF Virtio probe failed:%d\n", err);
if (cfv->vr_rx)
vdev->vringh_config->del_vrhs(cfv->vdev);
if (cfv->vdev)
vdev->config->del_vqs(cfv->vdev);
free_netdev(netdev);
return err;
}
static void cfv_remove(struct virtio_device *vdev)
{
struct cfv_info *cfv = vdev->priv;
rtnl_lock();
dev_close(cfv->ndev);
rtnl_unlock();
tasklet_kill(&cfv->tx_release_tasklet);
debugfs_remove_recursive(cfv->debugfs);
vringh_kiov_cleanup(&cfv->ctx.riov);
vdev->config->reset(vdev);
vdev->vringh_config->del_vrhs(cfv->vdev);
cfv->vr_rx = NULL;
vdev->config->del_vqs(cfv->vdev);
unregister_netdev(cfv->ndev);
}
static struct virtio_device_id id_table[] = {
{ VIRTIO_ID_CAIF, VIRTIO_DEV_ANY_ID },
{ 0 },
};
static unsigned int features[] = {
};
static struct virtio_driver caif_virtio_driver = {
.feature_table = features,
.feature_table_size = ARRAY_SIZE(features),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,
.probe = cfv_probe,
.remove = cfv_remove,
};
module_virtio_driver(caif_virtio_driver);
MODULE_DEVICE_TABLE(virtio, id_table);
drivers/net/virtio_net.c
View file @ 736a2dd2
......@@ -39,7 +39,6 @@ module_param(gso, bool, 0444);
#define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
#define GOOD_COPY_LEN 128
#define VIRTNET_SEND_COMMAND_SG_MAX 2
#define VIRTNET_DRIVER_VERSION "1.0.0"
struct virtnet_stats {
......@@ -444,7 +443,7 @@ static int add_recvbuf_small(struct receive_queue *rq, gfp_t gfp)
skb_to_sgvec(skb, rq->sg + 1, 0, skb->len);
err = virtqueue_add_buf(rq->vq, rq->sg, 0, 2, skb, gfp);
err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp);
if (err < 0)
dev_kfree_skb(skb);
......@@ -489,8 +488,8 @@ static int add_recvbuf_big(struct receive_queue *rq, gfp_t gfp)
/* chain first in list head */
first->private = (unsigned long)list;
err = virtqueue_add_buf(rq->vq, rq->sg, 0, MAX_SKB_FRAGS + 2,
first, gfp);
err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
first, gfp);
if (err < 0)
give_pages(rq, first);
......@@ -508,7 +507,7 @@ static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp)
sg_init_one(rq->sg, page_address(page), PAGE_SIZE);
err = virtqueue_add_buf(rq->vq, rq->sg, 0, 1, page, gfp);
err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, page, gfp);
if (err < 0)
give_pages(rq, page);
......@@ -582,7 +581,7 @@ static void refill_work(struct work_struct *work)
bool still_empty;
int i;
for (i = 0; i < vi->max_queue_pairs; i++) {
for (i = 0; i < vi->curr_queue_pairs; i++) {
struct receive_queue *rq = &vi->rq[i];
napi_disable(&rq->napi);
......@@ -637,7 +636,7 @@ static int virtnet_open(struct net_device *dev)
struct virtnet_info *vi = netdev_priv(dev);
int i;
for (i = 0; i < vi->max_queue_pairs; i++) {
for (i = 0; i < vi->curr_queue_pairs; i++) {
/* Make sure we have some buffers: if oom use wq. */
if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
schedule_delayed_work(&vi->refill, 0);
......@@ -711,8 +710,7 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
sg_set_buf(sq->sg, &hdr->hdr, sizeof hdr->hdr);
num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
return virtqueue_add_buf(sq->vq, sq->sg, num_sg,
0, skb, GFP_ATOMIC);
return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
}
static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
......@@ -767,32 +765,35 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
* never fail unless improperly formated.
*/
static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
struct scatterlist *data, int out, int in)
struct scatterlist *out,
struct scatterlist *in)
{
struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2];
struct scatterlist *sgs[4], hdr, stat;
struct virtio_net_ctrl_hdr ctrl;
virtio_net_ctrl_ack status = ~0;
unsigned int tmp;
int i;
unsigned out_num = 0, in_num = 0, tmp;
/* Caller should know better */
BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ||
(out + in > VIRTNET_SEND_COMMAND_SG_MAX));
out++; /* Add header */
in++; /* Add return status */
BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
ctrl.class = class;
ctrl.cmd = cmd;
/* Add header */
sg_init_one(&hdr, &ctrl, sizeof(ctrl));
sgs[out_num++] = &hdr;
sg_init_table(sg, out + in);
if (out)
sgs[out_num++] = out;
if (in)
sgs[out_num + in_num++] = in;
sg_set_buf(&sg[0], &ctrl, sizeof(ctrl));
for_each_sg(data, s, out + in - 2, i)
sg_set_buf(&sg[i + 1], sg_virt(s), s->length);
sg_set_buf(&sg[out + in - 1], &status, sizeof(status));
/* Add return status. */
sg_init_one(&stat, &status, sizeof(status));
sgs[out_num + in_num++] = &stat;
BUG_ON(virtqueue_add_buf(vi->cvq, sg, out, in, vi, GFP_ATOMIC) < 0);
BUG_ON(out_num + in_num > ARRAY_SIZE(sgs));
BUG_ON(virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC)
< 0);
virtqueue_kick(vi->cvq);
......@@ -821,7 +822,7 @@ static int virtnet_set_mac_address(struct net_device *dev, void *p)
sg_init_one(&sg, addr->sa_data, dev->addr_len);
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
VIRTIO_NET_CTRL_MAC_ADDR_SET,
&sg, 1, 0)) {
&sg, NULL)) {
dev_warn(&vdev->dev,
"Failed to set mac address by vq command.\n");
return -EINVAL;
......@@ -889,8 +890,7 @@ static void virtnet_ack_link_announce(struct virtnet_info *vi)
{
rtnl_lock();
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL,
0, 0))
VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL, NULL))
dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
rtnl_unlock();
}
......@@ -900,6 +900,7 @@ static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
struct scatterlist sg;
struct virtio_net_ctrl_mq s;
struct net_device *dev = vi->dev;
int i;
if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
return 0;
......@@ -908,12 +909,16 @@ static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
sg_init_one(&sg, &s, sizeof(s));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg, 1, 0)){
VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg, NULL)) {
dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
queue_pairs);
return -EINVAL;
} else
} else {
for (i = vi->curr_queue_pairs; i < queue_pairs; i++)
if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
schedule_delayed_work(&vi->refill, 0);
vi->curr_queue_pairs = queue_pairs;
}
return 0;
}
......@@ -955,7 +960,7 @@ static void virtnet_set_rx_mode(struct net_device *dev)
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
VIRTIO_NET_CTRL_RX_PROMISC,
sg, 1, 0))
sg, NULL))
dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
promisc ? "en" : "dis");
......@@ -963,7 +968,7 @@ static void virtnet_set_rx_mode(struct net_device *dev)
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
VIRTIO_NET_CTRL_RX_ALLMULTI,
sg, 1, 0))
sg, NULL))
dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
allmulti ? "en" : "dis");
......@@ -1000,7 +1005,7 @@ static void virtnet_set_rx_mode(struct net_device *dev)
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
VIRTIO_NET_CTRL_MAC_TABLE_SET,
sg, 2, 0))
sg, NULL))
dev_warn(&dev->dev, "Failed to set MAC fitler table.\n");
kfree(buf);
......@@ -1015,7 +1020,7 @@ static int virtnet_vlan_rx_add_vid(struct net_device *dev,
sg_init_one(&sg, &vid, sizeof(vid));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0))
VIRTIO_NET_CTRL_VLAN_ADD, &sg, NULL))
dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
return 0;
}
......@@ -1029,7 +1034,7 @@ static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
sg_init_one(&sg, &vid, sizeof(vid));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0))
VIRTIO_NET_CTRL_VLAN_DEL, &sg, NULL))
dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
return 0;
}
......@@ -1570,7 +1575,7 @@ static int virtnet_probe(struct virtio_device *vdev)
}
/* Last of all, set up some receive buffers. */
for (i = 0; i < vi->max_queue_pairs; i++) {
for (i = 0; i < vi->curr_queue_pairs; i++) {
try_fill_recv(&vi->rq[i], GFP_KERNEL);
/* If we didn't even get one input buffer, we're useless. */
......@@ -1694,7 +1699,7 @@ static int virtnet_restore(struct virtio_device *vdev)
netif_device_attach(vi->dev);
for (i = 0; i < vi->max_queue_pairs; i++)
for (i = 0; i < vi->curr_queue_pairs; i++)
if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
schedule_delayed_work(&vi->refill, 0);
......
drivers/rpmsg/virtio_rpmsg_bus.c
View file @ 736a2dd2
......@@ -757,14 +757,14 @@ int rpmsg_send_offchannel_raw(struct rpmsg_channel *rpdev, u32 src, u32 dst,
mutex_lock(&vrp->tx_lock);
/* add message to the remote processor's virtqueue */
err = virtqueue_add_buf(vrp->svq, &sg, 1, 0, msg, GFP_KERNEL);
err = virtqueue_add_outbuf(vrp->svq, &sg, 1, msg, GFP_KERNEL);
if (err) {
/*
* need to reclaim the buffer here, otherwise it's lost
* (memory won't leak, but rpmsg won't use it again for TX).
* this will wait for a buffer management overhaul.
*/
dev_err(dev, "virtqueue_add_buf failed: %d\n", err);
dev_err(dev, "virtqueue_add_outbuf failed: %d\n", err);
goto out;
}
......@@ -839,7 +839,7 @@ static void rpmsg_recv_done(struct virtqueue *rvq)
sg_init_one(&sg, msg, RPMSG_BUF_SIZE);
/* add the buffer back to the remote processor's virtqueue */
err = virtqueue_add_buf(vrp->rvq, &sg, 0, 1, msg, GFP_KERNEL);
err = virtqueue_add_inbuf(vrp->rvq, &sg, 1, msg, GFP_KERNEL);
if (err < 0) {
dev_err(dev, "failed to add a virtqueue buffer: %d\n", err);
return;
......@@ -972,7 +972,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
sg_init_one(&sg, cpu_addr, RPMSG_BUF_SIZE);
err = virtqueue_add_buf(vrp->rvq, &sg, 0, 1, cpu_addr,
err = virtqueue_add_inbuf(vrp->rvq, &sg, 1, cpu_addr,
GFP_KERNEL);
WARN_ON(err); /* sanity check; this can't really happen */
}
......
drivers/scsi/virtio_scsi.c
View file @ 736a2dd2
......@@ -13,6 +13,8 @@
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/mempool.h>
......@@ -20,12 +22,14 @@
#include <linux/virtio_ids.h>
#include <linux/virtio_config.h>
#include <linux/virtio_scsi.h>
#include <linux/cpu.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#define VIRTIO_SCSI_MEMPOOL_SZ 64
#define VIRTIO_SCSI_EVENT_LEN 8
#define VIRTIO_SCSI_VQ_BASE 2
/* Command queue element */
struct virtio_scsi_cmd {
......@@ -57,27 +61,61 @@ struct virtio_scsi_vq {
struct virtqueue *vq;
};
/* Per-target queue state */
/*
* Per-target queue state.
*
* This struct holds the data needed by the queue steering policy. When a
* target is sent multiple requests, we need to drive them to the same queue so
* that FIFO processing order is kept. However, if a target was idle, we can
* choose a queue arbitrarily. In this case the queue is chosen according to
* the current VCPU, so the driver expects the number of request queues to be
* equal to the number of VCPUs. This makes it easy and fast to select the
* queue, and also lets the driver optimize the IRQ affinity for the virtqueues
* (each virtqueue's affinity is set to the CPU that "owns" the queue).
*
* An interesting effect of this policy is that only writes to req_vq need to
* take the tgt_lock. Read can be done outside the lock because:
*
* - writes of req_vq only occur when atomic_inc_return(&tgt->reqs) returns 1.
* In that case, no other CPU is reading req_vq: even if they were in
* virtscsi_queuecommand_multi, they would be spinning on tgt_lock.
*
* - reads of req_vq only occur when the target is not idle (reqs != 0).
* A CPU that enters virtscsi_queuecommand_multi will not modify req_vq.
*
* Similarly, decrements of reqs are never concurrent with writes of req_vq.
* Thus they can happen outside the tgt_lock, provided of course we make reqs
* an atomic_t.
*/
struct virtio_scsi_target_state {
/* Protects sg. Lock hierarchy is tgt_lock -> vq_lock. */
/* This spinlock never held at the same time as vq_lock. */
spinlock_t tgt_lock;
/* For sglist construction when adding commands to the virtqueue. */
struct scatterlist sg[];
/* Count of outstanding requests. */
atomic_t reqs;
/* Currently active virtqueue for requests sent to this target. */
struct virtio_scsi_vq *req_vq;
};
/* Driver instance state */
struct virtio_scsi {
struct virtio_device *vdev;
struct virtio_scsi_vq ctrl_vq;
struct virtio_scsi_vq event_vq;
struct virtio_scsi_vq req_vq;
/* Get some buffers ready for event vq */
struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
struct virtio_scsi_target_state *tgt[];
u32 num_queues;
/* If the affinity hint is set for virtqueues */
bool affinity_hint_set;
/* CPU hotplug notifier */
struct notifier_block nb;
struct virtio_scsi_vq ctrl_vq;
struct virtio_scsi_vq event_vq;
struct virtio_scsi_vq req_vqs[];
};
static struct kmem_cache *virtscsi_cmd_cache;
......@@ -107,11 +145,13 @@ static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid)
*
* Called with vq_lock held.
*/
static void virtscsi_complete_cmd(void *buf)
static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf)
{
struct virtio_scsi_cmd *cmd = buf;
struct scsi_cmnd *sc = cmd->sc;
struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd;
struct virtio_scsi_target_state *tgt =
scsi_target(sc->device)->hostdata;
dev_dbg(&sc->device->sdev_gendev,
"cmd %p response %u status %#02x sense_len %u\n",
......@@ -166,32 +206,71 @@ static void virtscsi_complete_cmd(void *buf)
mempool_free(cmd, virtscsi_cmd_pool);
sc->scsi_done(sc);
atomic_dec(&tgt->reqs);
}
static void virtscsi_vq_done(struct virtqueue *vq, void (*fn)(void *buf))
static void virtscsi_vq_done(struct virtio_scsi *vscsi,
struct virtio_scsi_vq *virtscsi_vq,
void (*fn)(struct virtio_scsi *vscsi, void *buf))
{
void *buf;
unsigned int len;
unsigned long flags;
struct virtqueue *vq = virtscsi_vq->vq;
spin_lock_irqsave(&virtscsi_vq->vq_lock, flags);
do {
virtqueue_disable_cb(vq);
while ((buf = virtqueue_get_buf(vq, &len)) != NULL)
fn(buf);
fn(vscsi, buf);
} while (!virtqueue_enable_cb(vq));
spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags);
}
static void virtscsi_req_done(struct virtqueue *vq)
{
struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
struct virtio_scsi *vscsi = shost_priv(sh);
unsigned long flags;
int index = vq->index - VIRTIO_SCSI_VQ_BASE;
struct virtio_scsi_vq *req_vq = &vscsi->req_vqs[index];
spin_lock_irqsave(&vscsi->req_vq.vq_lock, flags);
virtscsi_vq_done(vq, virtscsi_complete_cmd);
spin_unlock_irqrestore(&vscsi->req_vq.vq_lock, flags);
/*
* Read req_vq before decrementing the reqs field in
* virtscsi_complete_cmd.
*
* With barriers:
*
* CPU #0 virtscsi_queuecommand_multi (CPU #1)
* ------------------------------------------------------------
* lock vq_lock
* read req_vq
* read reqs (reqs = 1)
* write reqs (reqs = 0)
* increment reqs (reqs = 1)
* write req_vq
*
* Possible reordering without barriers:
*
* CPU #0 virtscsi_queuecommand_multi (CPU #1)
* ------------------------------------------------------------
* lock vq_lock
* read reqs (reqs = 1)
* write reqs (reqs = 0)
* increment reqs (reqs = 1)
* write req_vq
* read (wrong) req_vq
*
* We do not need a full smp_rmb, because req_vq is required to get
* to tgt->reqs: tgt is &vscsi->tgt[sc->device->id], where sc is stored
* in the virtqueue as the user token.
*/
smp_read_barrier_depends();
virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd);
};
static void virtscsi_complete_free(void *buf)
static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf)
{
struct virtio_scsi_cmd *cmd = buf;
......@@ -205,11 +284,8 @@ static void virtscsi_ctrl_done(struct virtqueue *vq)
{
struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
struct virtio_scsi *vscsi = shost_priv(sh);
unsigned long flags;
spin_lock_irqsave(&vscsi->ctrl_vq.vq_lock, flags);
virtscsi_vq_done(vq, virtscsi_complete_free);
spin_unlock_irqrestore(&vscsi->ctrl_vq.vq_lock, flags);
virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free);
};
static int virtscsi_kick_event(struct virtio_scsi *vscsi,
......@@ -223,8 +299,8 @@ static int virtscsi_kick_event(struct virtio_scsi *vscsi,
spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
err = virtqueue_add_buf(vscsi->event_vq.vq, &sg, 0, 1, event_node,
GFP_ATOMIC);
err = virtqueue_add_inbuf(vscsi->event_vq.vq, &sg, 1, event_node,
GFP_ATOMIC);
if (!err)
virtqueue_kick(vscsi->event_vq.vq);
......@@ -254,7 +330,7 @@ static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi)
}
static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
struct virtio_scsi_event *event)
struct virtio_scsi_event *event)
{
struct scsi_device *sdev;
struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
......@@ -332,7 +408,7 @@ static void virtscsi_handle_event(struct work_struct *work)
virtscsi_kick_event(vscsi, event_node);
}
static void virtscsi_complete_event(void *buf)
static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf)
{
struct virtio_scsi_event_node *event_node = buf;
......@@ -344,82 +420,65 @@ static void virtscsi_event_done(struct virtqueue *vq)
{
struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
struct virtio_scsi *vscsi = shost_priv(sh);
unsigned long flags;
spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
virtscsi_vq_done(vq, virtscsi_complete_event);
spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags);
virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event);
};
static void virtscsi_map_sgl(struct scatterlist *sg, unsigned int *p_idx,
struct scsi_data_buffer *sdb)
{
struct sg_table *table = &sdb->table;
struct scatterlist *sg_elem;
unsigned int idx = *p_idx;
int i;
for_each_sg(table->sgl, sg_elem, table->nents, i)
sg[idx++] = *sg_elem;
*p_idx = idx;
}
/**
* virtscsi_map_cmd - map a scsi_cmd to a virtqueue scatterlist
* @vscsi : virtio_scsi state
* virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue
* @vq : the struct virtqueue we're talking about
* @cmd : command structure
* @out_num : number of read-only elements
* @in_num : number of write-only elements
* @req_size : size of the request buffer
* @resp_size : size of the response buffer
*
* Called with tgt_lock held.
* @gfp : flags to use for memory allocations
*/
static void virtscsi_map_cmd(struct virtio_scsi_target_state *tgt,
struct virtio_scsi_cmd *cmd,
unsigned *out_num, unsigned *in_num,
size_t req_size, size_t resp_size)
static int virtscsi_add_cmd(struct virtqueue *vq,
struct virtio_scsi_cmd *cmd,
size_t req_size, size_t resp_size, gfp_t gfp)
{
struct scsi_cmnd *sc = cmd->sc;
struct scatterlist *sg = tgt->sg;
unsigned int idx = 0;
struct scatterlist *sgs[4], req, resp;
struct sg_table *out, *in;
unsigned out_num = 0, in_num = 0;
out = in = NULL;
if (sc && sc->sc_data_direction != DMA_NONE) {
if (sc->sc_data_direction != DMA_FROM_DEVICE)
out = &scsi_out(sc)->table;
if (sc->sc_data_direction != DMA_TO_DEVICE)
in = &scsi_in(sc)->table;
}
/* Request header. */
sg_set_buf(&sg[idx++], &cmd->req, req_size);
sg_init_one(&req, &cmd->req, req_size);
sgs[out_num++] = &req;
/* Data-out buffer. */
if (sc && sc->sc_data_direction != DMA_FROM_DEVICE)
virtscsi_map_sgl(sg, &idx, scsi_out(sc));
*out_num = idx;
if (out)
sgs[out_num++] = out->sgl;
/* Response header. */
sg_set_buf(&sg[idx++], &cmd->resp, resp_size);
sg_init_one(&resp, &cmd->resp, resp_size);
sgs[out_num + in_num++] = &resp;
/* Data-in buffer */
if (sc && sc->sc_data_direction != DMA_TO_DEVICE)
virtscsi_map_sgl(sg, &idx, scsi_in(sc));
if (in)
sgs[out_num + in_num++] = in->sgl;
*in_num = idx - *out_num;
return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, gfp);
}
static int virtscsi_kick_cmd(struct virtio_scsi_target_state *tgt,
struct virtio_scsi_vq *vq,
static int virtscsi_kick_cmd(struct virtio_scsi_vq *vq,
struct virtio_scsi_cmd *cmd,
size_t req_size, size_t resp_size, gfp_t gfp)
{
unsigned int out_num, in_num;
unsigned long flags;
int err;
bool needs_kick = false;
spin_lock_irqsave(&tgt->tgt_lock, flags);
virtscsi_map_cmd(tgt, cmd, &out_num, &in_num, req_size, resp_size);
spin_lock(&vq->vq_lock);
err = virtqueue_add_buf(vq->vq, tgt->sg, out_num, in_num, cmd, gfp);
spin_unlock(&tgt->tgt_lock);
spin_lock_irqsave(&vq->vq_lock, flags);
err = virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size, gfp);
if (!err)
needs_kick = virtqueue_kick_prepare(vq->vq);
......@@ -430,10 +489,10 @@ static int virtscsi_kick_cmd(struct virtio_scsi_target_state *tgt,
return err;
}
static int virtscsi_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
static int virtscsi_queuecommand(struct virtio_scsi *vscsi,
struct virtio_scsi_vq *req_vq,
struct scsi_cmnd *sc)
{
struct virtio_scsi *vscsi = shost_priv(sh);
struct virtio_scsi_target_state *tgt = vscsi->tgt[sc->device->id];
struct virtio_scsi_cmd *cmd;
int ret;
......@@ -467,7 +526,7 @@ static int virtscsi_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE);
memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len);
if (virtscsi_kick_cmd(tgt, &vscsi->req_vq, cmd,
if (virtscsi_kick_cmd(req_vq, cmd,
sizeof cmd->req.cmd, sizeof cmd->resp.cmd,
GFP_ATOMIC) == 0)
ret = 0;
......@@ -478,14 +537,62 @@ static int virtscsi_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
return ret;
}
static int virtscsi_queuecommand_single(struct Scsi_Host *sh,
struct scsi_cmnd *sc)
{
struct virtio_scsi *vscsi = shost_priv(sh);
struct virtio_scsi_target_state *tgt =
scsi_target(sc->device)->hostdata;
atomic_inc(&tgt->reqs);
return virtscsi_queuecommand(vscsi, &vscsi->req_vqs[0], sc);
}
static struct virtio_scsi_vq *virtscsi_pick_vq(struct virtio_scsi *vscsi,
struct virtio_scsi_target_state *tgt)
{
struct virtio_scsi_vq *vq;
unsigned long flags;
u32 queue_num;
spin_lock_irqsave(&tgt->tgt_lock, flags);
/*
* The memory barrier after atomic_inc_return matches
* the smp_read_barrier_depends() in virtscsi_req_done.
*/
if (atomic_inc_return(&tgt->reqs) > 1)
vq = ACCESS_ONCE(tgt->req_vq);
else {
queue_num = smp_processor_id();
while (unlikely(queue_num >= vscsi->num_queues))
queue_num -= vscsi->num_queues;
tgt->req_vq = vq = &vscsi->req_vqs[queue_num];
}
spin_unlock_irqrestore(&tgt->tgt_lock, flags);
return vq;
}
static int virtscsi_queuecommand_multi(struct Scsi_Host *sh,
struct scsi_cmnd *sc)
{
struct virtio_scsi *vscsi = shost_priv(sh);
struct virtio_scsi_target_state *tgt =
scsi_target(sc->device)->hostdata;
struct virtio_scsi_vq *req_vq = virtscsi_pick_vq(vscsi, tgt);
return virtscsi_queuecommand(vscsi, req_vq, sc);
}
static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
{
DECLARE_COMPLETION_ONSTACK(comp);
struct virtio_scsi_target_state *tgt = vscsi->tgt[cmd->sc->device->id];
int ret = FAILED;
cmd->comp = &comp;
if (virtscsi_kick_cmd(tgt, &vscsi->ctrl_vq, cmd,
if (virtscsi_kick_cmd(&vscsi->ctrl_vq, cmd,
sizeof cmd->req.tmf, sizeof cmd->resp.tmf,
GFP_NOIO) < 0)
goto out;
......@@ -547,18 +654,57 @@ static int virtscsi_abort(struct scsi_cmnd *sc)
return virtscsi_tmf(vscsi, cmd);
}
static struct scsi_host_template virtscsi_host_template = {
static int virtscsi_target_alloc(struct scsi_target *starget)
{
struct virtio_scsi_target_state *tgt =
kmalloc(sizeof(*tgt), GFP_KERNEL);
if (!tgt)
return -ENOMEM;
spin_lock_init(&tgt->tgt_lock);
atomic_set(&tgt->reqs, 0);
tgt->req_vq = NULL;
starget->hostdata = tgt;
return 0;
}
static void virtscsi_target_destroy(struct scsi_target *starget)
{
struct virtio_scsi_target_state *tgt = starget->hostdata;
kfree(tgt);
}
static struct scsi_host_template virtscsi_host_template_single = {
.module = THIS_MODULE,
.name = "Virtio SCSI HBA",
.proc_name = "virtio_scsi",
.this_id = -1,
.queuecommand = virtscsi_queuecommand_single,
.eh_abort_handler = virtscsi_abort,
.eh_device_reset_handler = virtscsi_device_reset,
.can_queue = 1024,
.dma_boundary = UINT_MAX,
.use_clustering = ENABLE_CLUSTERING,
.target_alloc = virtscsi_target_alloc,
.target_destroy = virtscsi_target_destroy,
};
static struct scsi_host_template virtscsi_host_template_multi = {
.module = THIS_MODULE,
.name = "Virtio SCSI HBA",
.proc_name = "virtio_scsi",
.queuecommand = virtscsi_queuecommand,
.this_id = -1,
.queuecommand = virtscsi_queuecommand_multi,
.eh_abort_handler = virtscsi_abort,
.eh_device_reset_handler = virtscsi_device_reset,
.can_queue = 1024,
.dma_boundary = UINT_MAX,
.use_clustering = ENABLE_CLUSTERING,
.target_alloc = virtscsi_target_alloc,
.target_destroy = virtscsi_target_destroy,
};
#define virtscsi_config_get(vdev, fld) \
......@@ -578,29 +724,69 @@ static struct scsi_host_template virtscsi_host_template = {
&__val, sizeof(__val)); \
})
static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
struct virtqueue *vq)
static void __virtscsi_set_affinity(struct virtio_scsi *vscsi, bool affinity)
{
spin_lock_init(&virtscsi_vq->vq_lock);
virtscsi_vq->vq = vq;
int i;
int cpu;
/* In multiqueue mode, when the number of cpu is equal
* to the number of request queues, we let the qeueues
* to be private to one cpu by setting the affinity hint
* to eliminate the contention.
*/
if ((vscsi->num_queues == 1 ||
vscsi->num_queues != num_online_cpus()) && affinity) {
if (vscsi->affinity_hint_set)
affinity = false;
else
return;
}
if (affinity) {
i = 0;
for_each_online_cpu(cpu) {
virtqueue_set_affinity(vscsi->req_vqs[i].vq, cpu);
i++;
}
vscsi->affinity_hint_set = true;
} else {
for (i = 0; i < vscsi->num_queues - VIRTIO_SCSI_VQ_BASE; i++)
virtqueue_set_affinity(vscsi->req_vqs[i].vq, -1);
vscsi->affinity_hint_set = false;
}
}
static struct virtio_scsi_target_state *virtscsi_alloc_tgt(
struct virtio_device *vdev, int sg_elems)
static void virtscsi_set_affinity(struct virtio_scsi *vscsi, bool affinity)
{
struct virtio_scsi_target_state *tgt;
gfp_t gfp_mask = GFP_KERNEL;
/* We need extra sg elements at head and tail. */
tgt = kmalloc(sizeof(*tgt) + sizeof(tgt->sg[0]) * (sg_elems + 2),
gfp_mask);
get_online_cpus();
__virtscsi_set_affinity(vscsi, affinity);
put_online_cpus();
}
if (!tgt)
return NULL;
static int virtscsi_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
struct virtio_scsi *vscsi = container_of(nfb, struct virtio_scsi, nb);
switch(action) {
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
__virtscsi_set_affinity(vscsi, true);
break;
default:
break;
}
return NOTIFY_OK;
}
spin_lock_init(&tgt->tgt_lock);
sg_init_table(tgt->sg, sg_elems + 2);
return tgt;
static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
struct virtqueue *vq)
{
spin_lock_init(&virtscsi_vq->vq_lock);
virtscsi_vq->vq = vq;
}
static void virtscsi_scan(struct virtio_device *vdev)
......@@ -614,46 +800,56 @@ static void virtscsi_remove_vqs(struct virtio_device *vdev)
{
struct Scsi_Host *sh = virtio_scsi_host(vdev);
struct virtio_scsi *vscsi = shost_priv(sh);
u32 i, num_targets;
virtscsi_set_affinity(vscsi, false);
/* Stop all the virtqueues. */
vdev->config->reset(vdev);
num_targets = sh->max_id;
for (i = 0; i < num_targets; i++) {
kfree(vscsi->tgt[i]);
vscsi->tgt[i] = NULL;
}
vdev->config->del_vqs(vdev);
}
static int virtscsi_init(struct virtio_device *vdev,
struct virtio_scsi *vscsi, int num_targets)
struct virtio_scsi *vscsi)
{
int err;
struct virtqueue *vqs[3];
u32 i, sg_elems;
u32 i;
u32 num_vqs;
vq_callback_t **callbacks;
const char **names;
struct virtqueue **vqs;
num_vqs = vscsi->num_queues + VIRTIO_SCSI_VQ_BASE;
vqs = kmalloc(num_vqs * sizeof(struct virtqueue *), GFP_KERNEL);
callbacks = kmalloc(num_vqs * sizeof(vq_callback_t *), GFP_KERNEL);
names = kmalloc(num_vqs * sizeof(char *), GFP_KERNEL);
if (!callbacks || !vqs || !names) {
err = -ENOMEM;
goto out;
}
vq_callback_t *callbacks[] = {
virtscsi_ctrl_done,
virtscsi_event_done,
virtscsi_req_done
};
const char *names[] = {
"control",
"event",
"request"
};
callbacks[0] = virtscsi_ctrl_done;
callbacks[1] = virtscsi_event_done;
names[0] = "control";
names[1] = "event";
for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++) {
callbacks[i] = virtscsi_req_done;
names[i] = "request";
}
/* Discover virtqueues and write information to configuration. */
err = vdev->config->find_vqs(vdev, 3, vqs, callbacks, names);
err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names);
if (err)
return err;
goto out;
virtscsi_init_vq(&vscsi->ctrl_vq, vqs[0]);
virtscsi_init_vq(&vscsi->event_vq, vqs[1]);
virtscsi_init_vq(&vscsi->req_vq, vqs[2]);
for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++)
virtscsi_init_vq(&vscsi->req_vqs[i - VIRTIO_SCSI_VQ_BASE],
vqs[i]);
virtscsi_set_affinity(vscsi, true);
virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
......@@ -661,19 +857,12 @@ static int virtscsi_init(struct virtio_device *vdev,
if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
virtscsi_kick_event_all(vscsi);
/* We need to know how many segments before we allocate. */
sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;
for (i = 0; i < num_targets; i++) {
vscsi->tgt[i] = virtscsi_alloc_tgt(vdev, sg_elems);
if (!vscsi->tgt[i]) {
err = -ENOMEM;
goto out;
}
}
err = 0;
out:
kfree(names);
kfree(callbacks);
kfree(vqs);
if (err)
virtscsi_remove_vqs(vdev);
return err;
......@@ -686,13 +875,21 @@ static int virtscsi_probe(struct virtio_device *vdev)
int err;
u32 sg_elems, num_targets;
u32 cmd_per_lun;
u32 num_queues;
struct scsi_host_template *hostt;
/* We need to know how many queues before we allocate. */
num_queues = virtscsi_config_get(vdev, num_queues) ? : 1;
/* Allocate memory and link the structs together. */
num_targets = virtscsi_config_get(vdev, max_target) + 1;
shost = scsi_host_alloc(&virtscsi_host_template,
sizeof(*vscsi)
+ num_targets * sizeof(struct virtio_scsi_target_state));
if (num_queues == 1)
hostt = &virtscsi_host_template_single;
else
hostt = &virtscsi_host_template_multi;
shost = scsi_host_alloc(hostt,
sizeof(*vscsi) + sizeof(vscsi->req_vqs[0]) * num_queues);
if (!shost)
return -ENOMEM;
......@@ -700,12 +897,20 @@ static int virtscsi_probe(struct virtio_device *vdev)
shost->sg_tablesize = sg_elems;
vscsi = shost_priv(shost);
vscsi->vdev = vdev;
vscsi->num_queues = num_queues;
vdev->priv = shost;
err = virtscsi_init(vdev, vscsi, num_targets);
err = virtscsi_init(vdev, vscsi);
if (err)
goto virtscsi_init_failed;
vscsi->nb.notifier_call = &virtscsi_cpu_callback;
err = register_hotcpu_notifier(&vscsi->nb);
if (err) {
pr_err("registering cpu notifier failed\n");
goto scsi_add_host_failed;
}
cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
......@@ -743,6 +948,8 @@ static void virtscsi_remove(struct virtio_device *vdev)
scsi_remove_host(shost);
unregister_hotcpu_notifier(&vscsi->nb);
virtscsi_remove_vqs(vdev);
scsi_host_put(shost);
}
......@@ -759,7 +966,7 @@ static int virtscsi_restore(struct virtio_device *vdev)
struct Scsi_Host *sh = virtio_scsi_host(vdev);
struct virtio_scsi *vscsi = shost_priv(sh);
return virtscsi_init(vdev, vscsi, sh->max_id);
return virtscsi_init(vdev, vscsi);
}
#endif
......@@ -794,8 +1001,7 @@ static int __init init(void)
virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0);
if (!virtscsi_cmd_cache) {
printk(KERN_ERR "kmem_cache_create() for "
"virtscsi_cmd_cache failed\n");
pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n");
goto error;
}
......@@ -804,8 +1010,7 @@ static int __init init(void)
mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ,
virtscsi_cmd_cache);
if (!virtscsi_cmd_pool) {
printk(KERN_ERR "mempool_create() for"
"virtscsi_cmd_pool failed\n");
pr_err("mempool_create() for virtscsi_cmd_pool failed\n");
goto error;
}
ret = register_virtio_driver(&virtio_scsi_driver);
......
drivers/vhost/Kconfig
View file @ 736a2dd2
config VHOST_NET
tristate "Host kernel accelerator for virtio net"
depends on NET && EVENTFD && (TUN || !TUN) && (MACVTAP || !MACVTAP)
select VHOST_RING
---help---
This kernel module can be loaded in host kernel to accelerate
guest networking with virtio_net. Not to be confused with virtio_net
......@@ -12,7 +13,14 @@ config VHOST_NET
config VHOST_SCSI
tristate "VHOST_SCSI TCM fabric driver"
depends on TARGET_CORE && EVENTFD && m
select VHOST_RING
default n
---help---
Say M here to enable the vhost_scsi TCM fabric module
for use with virtio-scsi guests
config VHOST_RING
tristate
---help---
This option is selected by any driver which needs to access
the host side of a virtio ring.
drivers/vhost/Makefile
View file @ 736a2dd2
......@@ -3,3 +3,5 @@ vhost_net-y := vhost.o net.o
obj-$(CONFIG_VHOST_SCSI) += vhost_scsi.o
vhost_scsi-y := scsi.o
obj-$(CONFIG_VHOST_RING) += vringh.o
drivers/vhost/test.c
View file @ 736a2dd2
......@@ -282,7 +282,9 @@ static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
return vhost_test_reset_owner(n);
default:
mutex_lock(&n->dev.mutex);
r = vhost_dev_ioctl(&n->dev, ioctl, arg);
r = vhost_dev_ioctl(&n->dev, ioctl, argp);
if (r == -ENOIOCTLCMD)
r = vhost_vring_ioctl(&n->dev, ioctl, argp);
vhost_test_flush(n);
mutex_unlock(&n->dev.mutex);
return r;
......
drivers/vhost/vringh.c 0 → 100644
View file @ 736a2dd2
/*
* Helpers for the host side of a virtio ring.
*
* Since these may be in userspace, we use (inline) accessors.
*/
#include <linux/vringh.h>
#include <linux/virtio_ring.h>
#include <linux/kernel.h>
#include <linux/ratelimit.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/export.h>
static __printf(1,2) __cold void vringh_bad(const char *fmt, ...)
{
static DEFINE_RATELIMIT_STATE(vringh_rs,
DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
if (__ratelimit(&vringh_rs)) {
va_list ap;
va_start(ap, fmt);
printk(KERN_NOTICE "vringh:");
vprintk(fmt, ap);
va_end(ap);
}
}
/* Returns vring->num if empty, -ve on error. */
static inline int __vringh_get_head(const struct vringh *vrh,
int (*getu16)(u16 *val, const u16 *p),
u16 *last_avail_idx)
{
u16 avail_idx, i, head;
int err;
err = getu16(&avail_idx, &vrh->vring.avail->idx);
if (err) {
vringh_bad("Failed to access avail idx at %p",
&vrh->vring.avail->idx);
return err;
}
if (*last_avail_idx == avail_idx)
return vrh->vring.num;
/* Only get avail ring entries after they have been exposed by guest. */
virtio_rmb(vrh->weak_barriers);
i = *last_avail_idx & (vrh->vring.num - 1);
err = getu16(&head, &vrh->vring.avail->ring[i]);
if (err) {
vringh_bad("Failed to read head: idx %d address %p",
*last_avail_idx, &vrh->vring.avail->ring[i]);
return err;
}
if (head >= vrh->vring.num) {
vringh_bad("Guest says index %u > %u is available",
head, vrh->vring.num);
return -EINVAL;
}
(*last_avail_idx)++;
return head;
}
/* Copy some bytes to/from the iovec. Returns num copied. */
static inline ssize_t vringh_iov_xfer(struct vringh_kiov *iov,
void *ptr, size_t len,
int (*xfer)(void *addr, void *ptr,
size_t len))
{
int err, done = 0;
while (len && iov->i < iov->used) {
size_t partlen;
partlen = min(iov->iov[iov->i].iov_len, len);
err = xfer(iov->iov[iov->i].iov_base, ptr, partlen);
if (err)
return err;
done += partlen;
len -= partlen;
ptr += partlen;
iov->consumed += partlen;
iov->iov[iov->i].iov_len -= partlen;
iov->iov[iov->i].iov_base += partlen;
if (!iov->iov[iov->i].iov_len) {
/* Fix up old iov element then increment. */
iov->iov[iov->i].iov_len = iov->consumed;
iov->iov[iov->i].iov_base -= iov->consumed;
iov->consumed = 0;
iov->i++;
}
}
return done;
}
/* May reduce *len if range is shorter. */
static inline bool range_check(struct vringh *vrh, u64 addr, size_t *len,
struct vringh_range *range,
bool (*getrange)(struct vringh *,
u64, struct vringh_range *))
{
if (addr < range->start || addr > range->end_incl) {
if (!getrange(vrh, addr, range))
return false;
}
BUG_ON(addr < range->start || addr > range->end_incl);
/* To end of memory? */
if (unlikely(addr + *len == 0)) {
if (range->end_incl == -1ULL)
return true;
goto truncate;
}
/* Otherwise, don't wrap. */
if (addr + *len < addr) {
vringh_bad("Wrapping descriptor %zu@0x%llx",
*len, (unsigned long long)addr);
return false;
}
if (unlikely(addr + *len - 1 > range->end_incl))
goto truncate;
return true;
truncate:
*len = range->end_incl + 1 - addr;
return true;
}
static inline bool no_range_check(struct vringh *vrh, u64 addr, size_t *len,
struct vringh_range *range,
bool (*getrange)(struct vringh *,
u64, struct vringh_range *))
{
return true;
}
/* No reason for this code to be inline. */
static int move_to_indirect(int *up_next, u16 *i, void *addr,
const struct vring_desc *desc,
struct vring_desc **descs, int *desc_max)
{
/* Indirect tables can't have indirect. */
if (*up_next != -1) {
vringh_bad("Multilevel indirect %u->%u", *up_next, *i);
return -EINVAL;
}
if (unlikely(desc->len % sizeof(struct vring_desc))) {
vringh_bad("Strange indirect len %u", desc->len);
return -EINVAL;
}
/* We will check this when we follow it! */
if (desc->flags & VRING_DESC_F_NEXT)
*up_next = desc->next;
else
*up_next = -2;
*descs = addr;
*desc_max = desc->len / sizeof(struct vring_desc);
/* Now, start at the first indirect. */
*i = 0;
return 0;
}
static int resize_iovec(struct vringh_kiov *iov, gfp_t gfp)
{
struct kvec *new;
unsigned int flag, new_num = (iov->max_num & ~VRINGH_IOV_ALLOCATED) * 2;
if (new_num < 8)
new_num = 8;
flag = (iov->max_num & VRINGH_IOV_ALLOCATED);
if (flag)
new = krealloc(iov->iov, new_num * sizeof(struct iovec), gfp);
else {
new = kmalloc(new_num * sizeof(struct iovec), gfp);
if (new) {
memcpy(new, iov->iov,
iov->max_num * sizeof(struct iovec));
flag = VRINGH_IOV_ALLOCATED;
}
}
if (!new)
return -ENOMEM;
iov->iov = new;
iov->max_num = (new_num | flag);
return 0;
}
static u16 __cold return_from_indirect(const struct vringh *vrh, int *up_next,
struct vring_desc **descs, int *desc_max)
{
u16 i = *up_next;
*up_next = -1;
*descs = vrh->vring.desc;
*desc_max = vrh->vring.num;
return i;
}
static int slow_copy(struct vringh *vrh, void *dst, const void *src,
bool (*rcheck)(struct vringh *vrh, u64 addr, size_t *len,
struct vringh_range *range,
bool (*getrange)(struct vringh *vrh,
u64,
struct vringh_range *)),
bool (*getrange)(struct vringh *vrh,
u64 addr,
struct vringh_range *r),
struct vringh_range *range,
int (*copy)(void *dst, const void *src, size_t len))
{
size_t part, len = sizeof(struct vring_desc);
do {
u64 addr;
int err;
part = len;
addr = (u64)(unsigned long)src - range->offset;
if (!rcheck(vrh, addr, &part, range, getrange))
return -EINVAL;
err = copy(dst, src, part);
if (err)
return err;
dst += part;
src += part;
len -= part;
} while (len);
return 0;
}
static inline int
__vringh_iov(struct vringh *vrh, u16 i,
struct vringh_kiov *riov,
struct vringh_kiov *wiov,
bool (*rcheck)(struct vringh *vrh, u64 addr, size_t *len,
struct vringh_range *range,
bool (*getrange)(struct vringh *, u64,
struct vringh_range *)),
bool (*getrange)(struct vringh *, u64, struct vringh_range *),
gfp_t gfp,
int (*copy)(void *dst, const void *src, size_t len))
{
int err, count = 0, up_next, desc_max;
struct vring_desc desc, *descs;
struct vringh_range range = { -1ULL, 0 }, slowrange;
bool slow = false;
/* We start traversing vring's descriptor table. */
descs = vrh->vring.desc;
desc_max = vrh->vring.num;
up_next = -1;
if (riov)
riov->i = riov->used = 0;
else if (wiov)
wiov->i = wiov->used = 0;
else
/* You must want something! */
BUG();
for (;;) {
void *addr;
struct vringh_kiov *iov;
size_t len;
if (unlikely(slow))
err = slow_copy(vrh, &desc, &descs[i], rcheck, getrange,
&slowrange, copy);
else
err = copy(&desc, &descs[i], sizeof(desc));
if (unlikely(err))
goto fail;
if (unlikely(desc.flags & VRING_DESC_F_INDIRECT)) {
/* Make sure it's OK, and get offset. */
len = desc.len;
if (!rcheck(vrh, desc.addr, &len, &range, getrange)) {
err = -EINVAL;
goto fail;
}
if (unlikely(len != desc.len)) {
slow = true;
/* We need to save this range to use offset */
slowrange = range;
}
addr = (void *)(long)(desc.addr + range.offset);
err = move_to_indirect(&up_next, &i, addr, &desc,
&descs, &desc_max);
if (err)
goto fail;
continue;
}
if (count++ == vrh->vring.num) {
vringh_bad("Descriptor loop in %p", descs);
err = -ELOOP;
goto fail;
}
if (desc.flags & VRING_DESC_F_WRITE)
iov = wiov;
else {
iov = riov;
if (unlikely(wiov && wiov->i)) {
vringh_bad("Readable desc %p after writable",
&descs[i]);
err = -EINVAL;
goto fail;
}
}
if (!iov) {
vringh_bad("Unexpected %s desc",
!wiov ? "writable" : "readable");
err = -EPROTO;
goto fail;
}
again:
/* Make sure it's OK, and get offset. */
len = desc.len;
if (!rcheck(vrh, desc.addr, &len, &range, getrange)) {
err = -EINVAL;
goto fail;
}
addr = (void *)(unsigned long)(desc.addr + range.offset);
if (unlikely(iov->used == (iov->max_num & ~VRINGH_IOV_ALLOCATED))) {
err = resize_iovec(iov, gfp);
if (err)
goto fail;
}
iov->iov[iov->used].iov_base = addr;
iov->iov[iov->used].iov_len = len;
iov->used++;
if (unlikely(len != desc.len)) {
desc.len -= len;
desc.addr += len;
goto again;
}
if (desc.flags & VRING_DESC_F_NEXT) {
i = desc.next;
} else {
/* Just in case we need to finish traversing above. */
if (unlikely(up_next > 0)) {
i = return_from_indirect(vrh, &up_next,
&descs, &desc_max);
slow = false;
} else
break;
}
if (i >= desc_max) {
vringh_bad("Chained index %u > %u", i, desc_max);
err = -EINVAL;
goto fail;
}
}
return 0;
fail:
return err;
}
static inline int __vringh_complete(struct vringh *vrh,
const struct vring_used_elem *used,
unsigned int num_used,
int (*putu16)(u16 *p, u16 val),
int (*putused)(struct vring_used_elem *dst,
const struct vring_used_elem
*src, unsigned num))
{
struct vring_used *used_ring;
int err;
u16 used_idx, off;
used_ring = vrh->vring.used;
used_idx = vrh->last_used_idx + vrh->completed;
off = used_idx % vrh->vring.num;
/* Compiler knows num_used == 1 sometimes, hence extra check */
if (num_used > 1 && unlikely(off + num_used >= vrh->vring.num)) {
u16 part = vrh->vring.num - off;
err = putused(&used_ring->ring[off], used, part);
if (!err)
err = putused(&used_ring->ring[0], used + part,
num_used - part);
} else
err = putused(&used_ring->ring[off], used, num_used);
if (err) {
vringh_bad("Failed to write %u used entries %u at %p",
num_used, off, &used_ring->ring[off]);
return err;
}
/* Make sure buffer is written before we update index. */
virtio_wmb(vrh->weak_barriers);
err = putu16(&vrh->vring.used->idx, used_idx + num_used);
if (err) {
vringh_bad("Failed to update used index at %p",
&vrh->vring.used->idx);
return err;
}
vrh->completed += num_used;
return 0;
}
static inline int __vringh_need_notify(struct vringh *vrh,
int (*getu16)(u16 *val, const u16 *p))
{
bool notify;
u16 used_event;
int err;
/* Flush out used index update. This is paired with the
* barrier that the Guest executes when enabling
* interrupts. */
virtio_mb(vrh->weak_barriers);
/* Old-style, without event indices. */
if (!vrh->event_indices) {
u16 flags;
err = getu16(&flags, &vrh->vring.avail->flags);
if (err) {
vringh_bad("Failed to get flags at %p",
&vrh->vring.avail->flags);
return err;
}
return (!(flags & VRING_AVAIL_F_NO_INTERRUPT));
}
/* Modern: we know when other side wants to know. */
err = getu16(&used_event, &vring_used_event(&vrh->vring));
if (err) {
vringh_bad("Failed to get used event idx at %p",
&vring_used_event(&vrh->vring));
return err;
}
/* Just in case we added so many that we wrap. */
if (unlikely(vrh->completed > 0xffff))
notify = true;
else
notify = vring_need_event(used_event,
vrh->last_used_idx + vrh->completed,
vrh->last_used_idx);
vrh->last_used_idx += vrh->completed;
vrh->completed = 0;
return notify;
}
static inline bool __vringh_notify_enable(struct vringh *vrh,
int (*getu16)(u16 *val, const u16 *p),
int (*putu16)(u16 *p, u16 val))
{
u16 avail;
if (!vrh->event_indices) {
/* Old-school; update flags. */
if (putu16(&vrh->vring.used->flags, 0) != 0) {
vringh_bad("Clearing used flags %p",
&vrh->vring.used->flags);
return true;
}
} else {
if (putu16(&vring_avail_event(&vrh->vring),
vrh->last_avail_idx) != 0) {
vringh_bad("Updating avail event index %p",
&vring_avail_event(&vrh->vring));
return true;
}
}
/* They could have slipped one in as we were doing that: make
* sure it's written, then check again. */
virtio_mb(vrh->weak_barriers);
if (getu16(&avail, &vrh->vring.avail->idx) != 0) {
vringh_bad("Failed to check avail idx at %p",
&vrh->vring.avail->idx);
return true;
}
/* This is unlikely, so we just leave notifications enabled
* (if we're using event_indices, we'll only get one
* notification anyway). */
return avail == vrh->last_avail_idx;
}
static inline void __vringh_notify_disable(struct vringh *vrh,
int (*putu16)(u16 *p, u16 val))
{
if (!vrh->event_indices) {
/* Old-school; update flags. */
if (putu16(&vrh->vring.used->flags, VRING_USED_F_NO_NOTIFY)) {
vringh_bad("Setting used flags %p",
&vrh->vring.used->flags);
}
}
}
/* Userspace access helpers: in this case, addresses are really userspace. */
static inline int getu16_user(u16 *val, const u16 *p)
{
return get_user(*val, (__force u16 __user *)p);
}
static inline int putu16_user(u16 *p, u16 val)
{
return put_user(val, (__force u16 __user *)p);
}
static inline int copydesc_user(void *dst, const void *src, size_t len)
{
return copy_from_user(dst, (__force void __user *)src, len) ?
-EFAULT : 0;
}
static inline int putused_user(struct vring_used_elem *dst,
const struct vring_used_elem *src,
unsigned int num)
{
return copy_to_user((__force void __user *)dst, src,
sizeof(*dst) * num) ? -EFAULT : 0;
}
static inline int xfer_from_user(void *src, void *dst, size_t len)
{
return copy_from_user(dst, (__force void __user *)src, len) ?
-EFAULT : 0;
}
static inline int xfer_to_user(void *dst, void *src, size_t len)
{
return copy_to_user((__force void __user *)dst, src, len) ?
-EFAULT : 0;
}
/**
* vringh_init_user - initialize a vringh for a userspace vring.
* @vrh: the vringh to initialize.
* @features: the feature bits for this ring.
* @num: the number of elements.
* @weak_barriers: true if we only need memory barriers, not I/O.
* @desc: the userpace descriptor pointer.
* @avail: the userpace avail pointer.
* @used: the userpace used pointer.
*
* Returns an error if num is invalid: you should check pointers
* yourself!
*/
int vringh_init_user(struct vringh *vrh, u32 features,
unsigned int num, bool weak_barriers,
struct vring_desc __user *desc,
struct vring_avail __user *avail,
struct vring_used __user *used)
{
/* Sane power of 2 please! */
if (!num || num > 0xffff || (num & (num - 1))) {
vringh_bad("Bad ring size %u", num);
return -EINVAL;
}
vrh->event_indices = (features & (1 << VIRTIO_RING_F_EVENT_IDX));
vrh->weak_barriers = weak_barriers;
vrh->completed = 0;
vrh->last_avail_idx = 0;
vrh->last_used_idx = 0;
vrh->vring.num = num;
/* vring expects kernel addresses, but only used via accessors. */
vrh->vring.desc = (__force struct vring_desc *)desc;
vrh->vring.avail = (__force struct vring_avail *)avail;
vrh->vring.used = (__force struct vring_used *)used;
return 0;
}
EXPORT_SYMBOL(vringh_init_user);
/**
* vringh_getdesc_user - get next available descriptor from userspace ring.
* @vrh: the userspace vring.
* @riov: where to put the readable descriptors (or NULL)
* @wiov: where to put the writable descriptors (or NULL)
* @getrange: function to call to check ranges.
* @head: head index we received, for passing to vringh_complete_user().
*
* Returns 0 if there was no descriptor, 1 if there was, or -errno.
*
* Note that on error return, you can tell the difference between an
* invalid ring and a single invalid descriptor: in the former case,
* *head will be vrh->vring.num. You may be able to ignore an invalid
* descriptor, but there's not much you can do with an invalid ring.
*
* Note that you may need to clean up riov and wiov, even on error!
*/
int vringh_getdesc_user(struct vringh *vrh,
struct vringh_iov *riov,
struct vringh_iov *wiov,
bool (*getrange)(struct vringh *vrh,
u64 addr, struct vringh_range *r),
u16 *head)
{
int err;
*head = vrh->vring.num;
err = __vringh_get_head(vrh, getu16_user, &vrh->last_avail_idx);
if (err < 0)
return err;
/* Empty... */
if (err == vrh->vring.num)
return 0;
/* We need the layouts to be the identical for this to work */
BUILD_BUG_ON(sizeof(struct vringh_kiov) != sizeof(struct vringh_iov));
BUILD_BUG_ON(offsetof(struct vringh_kiov, iov) !=
offsetof(struct vringh_iov, iov));
BUILD_BUG_ON(offsetof(struct vringh_kiov, i) !=
offsetof(struct vringh_iov, i));
BUILD_BUG_ON(offsetof(struct vringh_kiov, used) !=
offsetof(struct vringh_iov, used));
BUILD_BUG_ON(offsetof(struct vringh_kiov, max_num) !=
offsetof(struct vringh_iov, max_num));
BUILD_BUG_ON(sizeof(struct iovec) != sizeof(struct kvec));
BUILD_BUG_ON(offsetof(struct iovec, iov_base) !=
offsetof(struct kvec, iov_base));
BUILD_BUG_ON(offsetof(struct iovec, iov_len) !=
offsetof(struct kvec, iov_len));
BUILD_BUG_ON(sizeof(((struct iovec *)NULL)->iov_base)
!= sizeof(((struct kvec *)NULL)->iov_base));
BUILD_BUG_ON(sizeof(((struct iovec *)NULL)->iov_len)
!= sizeof(((struct kvec *)NULL)->iov_len));
*head = err;
err = __vringh_iov(vrh, *head, (struct vringh_kiov *)riov,
(struct vringh_kiov *)wiov,
range_check, getrange, GFP_KERNEL, copydesc_user);
if (err)
return err;
return 1;
}
EXPORT_SYMBOL(vringh_getdesc_user);
/**
* vringh_iov_pull_user - copy bytes from vring_iov.
* @riov: the riov as passed to vringh_getdesc_user() (updated as we consume)
* @dst: the place to copy.
* @len: the maximum length to copy.
*
* Returns the bytes copied <= len or a negative errno.
*/
ssize_t vringh_iov_pull_user(struct vringh_iov *riov, void *dst, size_t len)
{
return vringh_iov_xfer((struct vringh_kiov *)riov,
dst, len, xfer_from_user);
}
EXPORT_SYMBOL(vringh_iov_pull_user);
/**
* vringh_iov_push_user - copy bytes into vring_iov.
* @wiov: the wiov as passed to vringh_getdesc_user() (updated as we consume)
* @dst: the place to copy.
* @len: the maximum length to copy.
*
* Returns the bytes copied <= len or a negative errno.
*/
ssize_t vringh_iov_push_user(struct vringh_iov *wiov,
const void *src, size_t len)
{
return vringh_iov_xfer((struct vringh_kiov *)wiov,
(void *)src, len, xfer_to_user);
}
EXPORT_SYMBOL(vringh_iov_push_user);
/**
* vringh_abandon_user - we've decided not to handle the descriptor(s).
* @vrh: the vring.
* @num: the number of descriptors to put back (ie. num
* vringh_get_user() to undo).
*
* The next vringh_get_user() will return the old descriptor(s) again.
*/
void vringh_abandon_user(struct vringh *vrh, unsigned int num)
{
/* We only update vring_avail_event(vr) when we want to be notified,
* so we haven't changed that yet. */
vrh->last_avail_idx -= num;
}
EXPORT_SYMBOL(vringh_abandon_user);
/**
* vringh_complete_user - we've finished with descriptor, publish it.
* @vrh: the vring.
* @head: the head as filled in by vringh_getdesc_user.
* @len: the length of data we have written.
*
* You should check vringh_need_notify_user() after one or more calls
* to this function.
*/
int vringh_complete_user(struct vringh *vrh, u16 head, u32 len)
{
struct vring_used_elem used;
used.id = head;
used.len = len;
return __vringh_complete(vrh, &used, 1, putu16_user, putused_user);
}
EXPORT_SYMBOL(vringh_complete_user);
/**
* vringh_complete_multi_user - we've finished with many descriptors.
* @vrh: the vring.
* @used: the head, length pairs.
* @num_used: the number of used elements.
*
* You should check vringh_need_notify_user() after one or more calls
* to this function.
*/
int vringh_complete_multi_user(struct vringh *vrh,
const struct vring_used_elem used[],
unsigned num_used)
{
return __vringh_complete(vrh, used, num_used,
putu16_user, putused_user);
}
EXPORT_SYMBOL(vringh_complete_multi_user);
/**
* vringh_notify_enable_user - we want to know if something changes.
* @vrh: the vring.
*
* This always enables notifications, but returns false if there are
* now more buffers available in the vring.
*/
bool vringh_notify_enable_user(struct vringh *vrh)
{
return __vringh_notify_enable(vrh, getu16_user, putu16_user);
}
EXPORT_SYMBOL(vringh_notify_enable_user);
/**
* vringh_notify_disable_user - don't tell us if something changes.
* @vrh: the vring.
*
* This is our normal running state: we disable and then only enable when
* we're going to sleep.
*/
void vringh_notify_disable_user(struct vringh *vrh)
{
__vringh_notify_disable(vrh, putu16_user);
}
EXPORT_SYMBOL(vringh_notify_disable_user);
/**
* vringh_need_notify_user - must we tell the other side about used buffers?
* @vrh: the vring we've called vringh_complete_user() on.
*
* Returns -errno or 0 if we don't need to tell the other side, 1 if we do.
*/
int vringh_need_notify_user(struct vringh *vrh)
{
return __vringh_need_notify(vrh, getu16_user);
}
EXPORT_SYMBOL(vringh_need_notify_user);
/* Kernelspace access helpers. */
static inline int getu16_kern(u16 *val, const u16 *p)
{
*val = ACCESS_ONCE(*p);
return 0;
}
static inline int putu16_kern(u16 *p, u16 val)
{
ACCESS_ONCE(*p) = val;
return 0;
}
static inline int copydesc_kern(void *dst, const void *src, size_t len)
{
memcpy(dst, src, len);
return 0;
}
static inline int putused_kern(struct vring_used_elem *dst,
const struct vring_used_elem *src,
unsigned int num)
{
memcpy(dst, src, num * sizeof(*dst));
return 0;
}
static inline int xfer_kern(void *src, void *dst, size_t len)
{
memcpy(dst, src, len);
return 0;
}
/**
* vringh_init_kern - initialize a vringh for a kernelspace vring.
* @vrh: the vringh to initialize.
* @features: the feature bits for this ring.
* @num: the number of elements.
* @weak_barriers: true if we only need memory barriers, not I/O.
* @desc: the userpace descriptor pointer.
* @avail: the userpace avail pointer.
* @used: the userpace used pointer.
*
* Returns an error if num is invalid.
*/
int vringh_init_kern(struct vringh *vrh, u32 features,
unsigned int num, bool weak_barriers,
struct vring_desc *desc,
struct vring_avail *avail,
struct vring_used *used)
{
/* Sane power of 2 please! */
if (!num || num > 0xffff || (num & (num - 1))) {
vringh_bad("Bad ring size %u", num);
return -EINVAL;
}
vrh->event_indices = (features & (1 << VIRTIO_RING_F_EVENT_IDX));
vrh->weak_barriers = weak_barriers;
vrh->completed = 0;
vrh->last_avail_idx = 0;
vrh->last_used_idx = 0;
vrh->vring.num = num;
vrh->vring.desc = desc;
vrh->vring.avail = avail;
vrh->vring.used = used;
return 0;
}
EXPORT_SYMBOL(vringh_init_kern);
/**
* vringh_getdesc_kern - get next available descriptor from kernelspace ring.
* @vrh: the kernelspace vring.
* @riov: where to put the readable descriptors (or NULL)
* @wiov: where to put the writable descriptors (or NULL)
* @head: head index we received, for passing to vringh_complete_kern().
* @gfp: flags for allocating larger riov/wiov.
*
* Returns 0 if there was no descriptor, 1 if there was, or -errno.
*
* Note that on error return, you can tell the difference between an
* invalid ring and a single invalid descriptor: in the former case,
* *head will be vrh->vring.num. You may be able to ignore an invalid
* descriptor, but there's not much you can do with an invalid ring.
*
* Note that you may need to clean up riov and wiov, even on error!
*/
int vringh_getdesc_kern(struct vringh *vrh,
struct vringh_kiov *riov,
struct vringh_kiov *wiov,
u16 *head,
gfp_t gfp)
{
int err;
err = __vringh_get_head(vrh, getu16_kern, &vrh->last_avail_idx);
if (err < 0)
return err;
/* Empty... */
if (err == vrh->vring.num)
return 0;
*head = err;
err = __vringh_iov(vrh, *head, riov, wiov, no_range_check, NULL,
gfp, copydesc_kern);
if (err)
return err;
return 1;
}
EXPORT_SYMBOL(vringh_getdesc_kern);
/**
* vringh_iov_pull_kern - copy bytes from vring_iov.
* @riov: the riov as passed to vringh_getdesc_kern() (updated as we consume)
* @dst: the place to copy.
* @len: the maximum length to copy.
*
* Returns the bytes copied <= len or a negative errno.
*/
ssize_t vringh_iov_pull_kern(struct vringh_kiov *riov, void *dst, size_t len)
{
return vringh_iov_xfer(riov, dst, len, xfer_kern);
}
EXPORT_SYMBOL(vringh_iov_pull_kern);
/**
* vringh_iov_push_kern - copy bytes into vring_iov.
* @wiov: the wiov as passed to vringh_getdesc_kern() (updated as we consume)
* @dst: the place to copy.
* @len: the maximum length to copy.
*
* Returns the bytes copied <= len or a negative errno.
*/
ssize_t vringh_iov_push_kern(struct vringh_kiov *wiov,
const void *src, size_t len)
{
return vringh_iov_xfer(wiov, (void *)src, len, xfer_kern);
}
EXPORT_SYMBOL(vringh_iov_push_kern);
/**
* vringh_abandon_kern - we've decided not to handle the descriptor(s).
* @vrh: the vring.
* @num: the number of descriptors to put back (ie. num
* vringh_get_kern() to undo).
*
* The next vringh_get_kern() will return the old descriptor(s) again.
*/
void vringh_abandon_kern(struct vringh *vrh, unsigned int num)
{
/* We only update vring_avail_event(vr) when we want to be notified,
* so we haven't changed that yet. */
vrh->last_avail_idx -= num;
}
EXPORT_SYMBOL(vringh_abandon_kern);
/**
* vringh_complete_kern - we've finished with descriptor, publish it.
* @vrh: the vring.
* @head: the head as filled in by vringh_getdesc_kern.
* @len: the length of data we have written.
*
* You should check vringh_need_notify_kern() after one or more calls
* to this function.
*/
int vringh_complete_kern(struct vringh *vrh, u16 head, u32 len)
{
struct vring_used_elem used;
used.id = head;
used.len = len;
return __vringh_complete(vrh, &used, 1, putu16_kern, putused_kern);
}
EXPORT_SYMBOL(vringh_complete_kern);
/**
* vringh_notify_enable_kern - we want to know if something changes.
* @vrh: the vring.
*
* This always enables notifications, but returns false if there are
* now more buffers available in the vring.
*/
bool vringh_notify_enable_kern(struct vringh *vrh)
{
return __vringh_notify_enable(vrh, getu16_kern, putu16_kern);
}
EXPORT_SYMBOL(vringh_notify_enable_kern);
/**
* vringh_notify_disable_kern - don't tell us if something changes.
* @vrh: the vring.
*
* This is our normal running state: we disable and then only enable when
* we're going to sleep.
*/
void vringh_notify_disable_kern(struct vringh *vrh)
{
__vringh_notify_disable(vrh, putu16_kern);
}
EXPORT_SYMBOL(vringh_notify_disable_kern);
/**
* vringh_need_notify_kern - must we tell the other side about used buffers?
* @vrh: the vring we've called vringh_complete_kern() on.
*
* Returns -errno or 0 if we don't need to tell the other side, 1 if we do.
*/
int vringh_need_notify_kern(struct vringh *vrh)
{
return __vringh_need_notify(vrh, getu16_kern);
}
EXPORT_SYMBOL(vringh_need_notify_kern);
drivers/virtio/virtio_balloon.c
View file @ 736a2dd2
......@@ -108,7 +108,7 @@ static void tell_host(struct virtio_balloon *vb, struct virtqueue *vq)
sg_init_one(&sg, vb->pfns, sizeof(vb->pfns[0]) * vb->num_pfns);
/* We should always be able to add one buffer to an empty queue. */
if (virtqueue_add_buf(vq, &sg, 1, 0, vb, GFP_KERNEL) < 0)
if (virtqueue_add_outbuf(vq, &sg, 1, vb, GFP_KERNEL) < 0)
BUG();
virtqueue_kick(vq);
......@@ -256,7 +256,7 @@ static void stats_handle_request(struct virtio_balloon *vb)
if (!virtqueue_get_buf(vq, &len))
return;
sg_init_one(&sg, vb->stats, sizeof(vb->stats));
if (virtqueue_add_buf(vq, &sg, 1, 0, vb, GFP_KERNEL) < 0)
if (virtqueue_add_outbuf(vq, &sg, 1, vb, GFP_KERNEL) < 0)
BUG();
virtqueue_kick(vq);
}
......@@ -341,7 +341,7 @@ static int init_vqs(struct virtio_balloon *vb)
* use it to signal us later.
*/
sg_init_one(&sg, vb->stats, sizeof vb->stats);
if (virtqueue_add_buf(vb->stats_vq, &sg, 1, 0, vb, GFP_KERNEL)
if (virtqueue_add_outbuf(vb->stats_vq, &sg, 1, vb, GFP_KERNEL)
< 0)
BUG();
virtqueue_kick(vb->stats_vq);
......
drivers/virtio/virtio_ring.c
View file @ 736a2dd2
......@@ -24,27 +24,6 @@
#include <linux/module.h>
#include <linux/hrtimer.h>
/* virtio guest is communicating with a virtual "device" that actually runs on
* a host processor. Memory barriers are used to control SMP effects. */
#ifdef CONFIG_SMP
/* Where possible, use SMP barriers which are more lightweight than mandatory
* barriers, because mandatory barriers control MMIO effects on accesses
* through relaxed memory I/O windows (which virtio-pci does not use). */
#define virtio_mb(vq) \
do { if ((vq)->weak_barriers) smp_mb(); else mb(); } while(0)
#define virtio_rmb(vq) \
do { if ((vq)->weak_barriers) smp_rmb(); else rmb(); } while(0)
#define virtio_wmb(vq) \
do { if ((vq)->weak_barriers) smp_wmb(); else wmb(); } while(0)
#else
/* We must force memory ordering even if guest is UP since host could be
* running on another CPU, but SMP barriers are defined to barrier() in that
* configuration. So fall back to mandatory barriers instead. */
#define virtio_mb(vq) mb()
#define virtio_rmb(vq) rmb()
#define virtio_wmb(vq) wmb()
#endif
#ifdef DEBUG
/* For development, we want to crash whenever the ring is screwed. */
#define BAD_RING(_vq, fmt, args...) \
......@@ -119,16 +98,36 @@ struct vring_virtqueue
#define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq)
static inline struct scatterlist *sg_next_chained(struct scatterlist *sg,
unsigned int *count)
{
return sg_next(sg);
}
static inline struct scatterlist *sg_next_arr(struct scatterlist *sg,
unsigned int *count)
{
if (--(*count) == 0)
return NULL;
return sg + 1;
}
/* Set up an indirect table of descriptors and add it to the queue. */
static int vring_add_indirect(struct vring_virtqueue *vq,
struct scatterlist sg[],
unsigned int out,
unsigned int in,
gfp_t gfp)
static inline int vring_add_indirect(struct vring_virtqueue *vq,
struct scatterlist *sgs[],
struct scatterlist *(*next)
(struct scatterlist *, unsigned int *),
unsigned int total_sg,
unsigned int total_out,
unsigned int total_in,
unsigned int out_sgs,
unsigned int in_sgs,
gfp_t gfp)
{
struct vring_desc *desc;
unsigned head;
int i;
struct scatterlist *sg;
int i, n;
/*
* We require lowmem mappings for the descriptors because
......@@ -137,25 +136,31 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
*/
gfp &= ~(__GFP_HIGHMEM | __GFP_HIGH);
desc = kmalloc((out + in) * sizeof(struct vring_desc), gfp);
desc = kmalloc(total_sg * sizeof(struct vring_desc), gfp);
if (!desc)
return -ENOMEM;
/* Transfer entries from the sg list into the indirect page */
for (i = 0; i < out; i++) {
desc[i].flags = VRING_DESC_F_NEXT;
desc[i].addr = sg_phys(sg);
desc[i].len = sg->length;
desc[i].next = i+1;
sg++;
/* Transfer entries from the sg lists into the indirect page */
i = 0;
for (n = 0; n < out_sgs; n++) {
for (sg = sgs[n]; sg; sg = next(sg, &total_out)) {
desc[i].flags = VRING_DESC_F_NEXT;
desc[i].addr = sg_phys(sg);
desc[i].len = sg->length;
desc[i].next = i+1;
i++;
}
}
for (; i < (out + in); i++) {
desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
desc[i].addr = sg_phys(sg);
desc[i].len = sg->length;
desc[i].next = i+1;
sg++;
for (; n < (out_sgs + in_sgs); n++) {
for (sg = sgs[n]; sg; sg = next(sg, &total_in)) {
desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
desc[i].addr = sg_phys(sg);
desc[i].len = sg->length;
desc[i].next = i+1;
i++;
}
}
BUG_ON(i != total_sg);
/* Last one doesn't continue. */
desc[i-1].flags &= ~VRING_DESC_F_NEXT;
......@@ -176,29 +181,20 @@ static int vring_add_indirect(struct vring_virtqueue *vq,
return head;
}
/**
* virtqueue_add_buf - expose buffer to other end
* @vq: the struct virtqueue we're talking about.
* @sg: the description of the buffer(s).
* @out_num: the number of sg readable by other side
* @in_num: the number of sg which are writable (after readable ones)
* @data: the token identifying the buffer.
* @gfp: how to do memory allocations (if necessary).
*
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error (ie. ENOSPC, ENOMEM).
*/
int virtqueue_add_buf(struct virtqueue *_vq,
struct scatterlist sg[],
unsigned int out,
unsigned int in,
void *data,
gfp_t gfp)
static inline int virtqueue_add(struct virtqueue *_vq,
struct scatterlist *sgs[],
struct scatterlist *(*next)
(struct scatterlist *, unsigned int *),
unsigned int total_out,
unsigned int total_in,
unsigned int out_sgs,
unsigned int in_sgs,
void *data,
gfp_t gfp)
{
struct vring_virtqueue *vq = to_vvq(_vq);
unsigned int i, avail, uninitialized_var(prev);
struct scatterlist *sg;
unsigned int i, n, avail, uninitialized_var(prev), total_sg;
int head;
START_USE(vq);
......@@ -218,46 +214,54 @@ int virtqueue_add_buf(struct virtqueue *_vq,
}
#endif
total_sg = total_in + total_out;
/* If the host supports indirect descriptor tables, and we have multiple
* buffers, then go indirect. FIXME: tune this threshold */
if (vq->indirect && (out + in) > 1 && vq->vq.num_free) {
head = vring_add_indirect(vq, sg, out, in, gfp);
if (vq->indirect && total_sg > 1 && vq->vq.num_free) {
head = vring_add_indirect(vq, sgs, next, total_sg, total_out,
total_in,
out_sgs, in_sgs, gfp);
if (likely(head >= 0))
goto add_head;
}
BUG_ON(out + in > vq->vring.num);
BUG_ON(out + in == 0);
BUG_ON(total_sg > vq->vring.num);
BUG_ON(total_sg == 0);
if (vq->vq.num_free < out + in) {
if (vq->vq.num_free < total_sg) {
pr_debug("Can't add buf len %i - avail = %i\n",
out + in, vq->vq.num_free);
total_sg, vq->vq.num_free);
/* FIXME: for historical reasons, we force a notify here if
* there are outgoing parts to the buffer. Presumably the
* host should service the ring ASAP. */
if (out)
if (out_sgs)
vq->notify(&vq->vq);
END_USE(vq);
return -ENOSPC;
}
/* We're about to use some buffers from the free list. */
vq->vq.num_free -= out + in;
head = vq->free_head;
for (i = vq->free_head; out; i = vq->vring.desc[i].next, out--) {
vq->vring.desc[i].flags = VRING_DESC_F_NEXT;
vq->vring.desc[i].addr = sg_phys(sg);
vq->vring.desc[i].len = sg->length;
prev = i;
sg++;
vq->vq.num_free -= total_sg;
head = i = vq->free_head;
for (n = 0; n < out_sgs; n++) {
for (sg = sgs[n]; sg; sg = next(sg, &total_out)) {
vq->vring.desc[i].flags = VRING_DESC_F_NEXT;
vq->vring.desc[i].addr = sg_phys(sg);
vq->vring.desc[i].len = sg->length;
prev = i;
i = vq->vring.desc[i].next;
}
}
for (; in; i = vq->vring.desc[i].next, in--) {
vq->vring.desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
vq->vring.desc[i].addr = sg_phys(sg);
vq->vring.desc[i].len = sg->length;
prev = i;
sg++;
for (; n < (out_sgs + in_sgs); n++) {
for (sg = sgs[n]; sg; sg = next(sg, &total_in)) {
vq->vring.desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
vq->vring.desc[i].addr = sg_phys(sg);
vq->vring.desc[i].len = sg->length;
prev = i;
i = vq->vring.desc[i].next;
}
}
/* Last one doesn't continue. */
vq->vring.desc[prev].flags &= ~VRING_DESC_F_NEXT;
......@@ -276,7 +280,7 @@ int virtqueue_add_buf(struct virtqueue *_vq,
/* Descriptors and available array need to be set before we expose the
* new available array entries. */
virtio_wmb(vq);
virtio_wmb(vq->weak_barriers);
vq->vring.avail->idx++;
vq->num_added++;
......@@ -290,8 +294,121 @@ int virtqueue_add_buf(struct virtqueue *_vq,
return 0;
}
/**
* virtqueue_add_buf - expose buffer to other end
* @vq: the struct virtqueue we're talking about.
* @sg: the description of the buffer(s).
* @out_num: the number of sg readable by other side
* @in_num: the number of sg which are writable (after readable ones)
* @data: the token identifying the buffer.
* @gfp: how to do memory allocations (if necessary).
*
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error (ie. ENOSPC, ENOMEM).
*/
int virtqueue_add_buf(struct virtqueue *_vq,
struct scatterlist sg[],
unsigned int out,
unsigned int in,
void *data,
gfp_t gfp)
{
struct scatterlist *sgs[2];
sgs[0] = sg;
sgs[1] = sg + out;
return virtqueue_add(_vq, sgs, sg_next_arr,
out, in, out ? 1 : 0, in ? 1 : 0, data, gfp);
}
EXPORT_SYMBOL_GPL(virtqueue_add_buf);
/**
* virtqueue_add_sgs - expose buffers to other end
* @vq: the struct virtqueue we're talking about.
* @sgs: array of terminated scatterlists.
* @out_num: the number of scatterlists readable by other side
* @in_num: the number of scatterlists which are writable (after readable ones)
* @data: the token identifying the buffer.
* @gfp: how to do memory allocations (if necessary).
*
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error (ie. ENOSPC, ENOMEM).
*/
int virtqueue_add_sgs(struct virtqueue *_vq,
struct scatterlist *sgs[],
unsigned int out_sgs,
unsigned int in_sgs,
void *data,
gfp_t gfp)
{
unsigned int i, total_out, total_in;
/* Count them first. */
for (i = total_out = total_in = 0; i < out_sgs; i++) {
struct scatterlist *sg;
for (sg = sgs[i]; sg; sg = sg_next(sg))
total_out++;
}
for (; i < out_sgs + in_sgs; i++) {
struct scatterlist *sg;
for (sg = sgs[i]; sg; sg = sg_next(sg))
total_in++;
}
return virtqueue_add(_vq, sgs, sg_next_chained,
total_out, total_in, out_sgs, in_sgs, data, gfp);
}
EXPORT_SYMBOL_GPL(virtqueue_add_sgs);
/**
* virtqueue_add_outbuf - expose output buffers to other end
* @vq: the struct virtqueue we're talking about.
* @sgs: array of scatterlists (need not be terminated!)
* @num: the number of scatterlists readable by other side
* @data: the token identifying the buffer.
* @gfp: how to do memory allocations (if necessary).
*
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error (ie. ENOSPC, ENOMEM).
*/
int virtqueue_add_outbuf(struct virtqueue *vq,
struct scatterlist sg[], unsigned int num,
void *data,
gfp_t gfp)
{
return virtqueue_add(vq, &sg, sg_next_arr, num, 0, 1, 0, data, gfp);
}
EXPORT_SYMBOL_GPL(virtqueue_add_outbuf);
/**
* virtqueue_add_inbuf - expose input buffers to other end
* @vq: the struct virtqueue we're talking about.
* @sgs: array of scatterlists (need not be terminated!)
* @num: the number of scatterlists writable by other side
* @data: the token identifying the buffer.
* @gfp: how to do memory allocations (if necessary).
*
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error (ie. ENOSPC, ENOMEM).
*/
int virtqueue_add_inbuf(struct virtqueue *vq,
struct scatterlist sg[], unsigned int num,
void *data,
gfp_t gfp)
{
return virtqueue_add(vq, &sg, sg_next_arr, 0, num, 0, 1, data, gfp);
}
EXPORT_SYMBOL_GPL(virtqueue_add_inbuf);
/**
* virtqueue_kick_prepare - first half of split virtqueue_kick call.
* @vq: the struct virtqueue
......@@ -312,7 +429,7 @@ bool virtqueue_kick_prepare(struct virtqueue *_vq)
START_USE(vq);
/* We need to expose available array entries before checking avail
* event. */
virtio_mb(vq);
virtio_mb(vq->weak_barriers);
old = vq->vring.avail->idx - vq->num_added;
new = vq->vring.avail->idx;
......@@ -436,7 +553,7 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len)
}
/* Only get used array entries after they have been exposed by host. */
virtio_rmb(vq);
virtio_rmb(vq->weak_barriers);
last_used = (vq->last_used_idx & (vq->vring.num - 1));
i = vq->vring.used->ring[last_used].id;
......@@ -460,7 +577,7 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len)
* the read in the next get_buf call. */
if (!(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) {
vring_used_event(&vq->vring) = vq->last_used_idx;
virtio_mb(vq);
virtio_mb(vq->weak_barriers);
}
#ifdef DEBUG
......@@ -513,7 +630,7 @@ bool virtqueue_enable_cb(struct virtqueue *_vq)
* entry. Always do both to keep code simple. */
vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
vring_used_event(&vq->vring) = vq->last_used_idx;
virtio_mb(vq);
virtio_mb(vq->weak_barriers);
if (unlikely(more_used(vq))) {
END_USE(vq);
return false;
......@@ -553,7 +670,7 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq)
/* TODO: tune this threshold */
bufs = (u16)(vq->vring.avail->idx - vq->last_used_idx) * 3 / 4;
vring_used_event(&vq->vring) = vq->last_used_idx + bufs;
virtio_mb(vq);
virtio_mb(vq->weak_barriers);
if (unlikely((u16)(vq->vring.used->idx - vq->last_used_idx) > bufs)) {
END_USE(vq);
return false;
......
include/linux/scatterlist.h
View file @ 736a2dd2
......@@ -171,6 +171,22 @@ static inline void sg_mark_end(struct scatterlist *sg)
sg->page_link &= ~0x01;
}
/**
* sg_unmark_end - Undo setting the end of the scatterlist
* @sg: SG entryScatterlist
*
* Description:
* Removes the termination marker from the given entry of the scatterlist.
*
**/
static inline void sg_unmark_end(struct scatterlist *sg)
{
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
#endif
sg->page_link &= ~0x02;
}
/**
* sg_phys - Return physical address of an sg entry
* @sg: SG entry
......
include/linux/virtio.h
View file @ 736a2dd2
......@@ -8,6 +8,7 @@
#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/gfp.h>
#include <linux/vringh.h>
/**
* virtqueue - a queue to register buffers for sending or receiving.
......@@ -40,6 +41,23 @@ int virtqueue_add_buf(struct virtqueue *vq,
void *data,
gfp_t gfp);
int virtqueue_add_outbuf(struct virtqueue *vq,
struct scatterlist sg[], unsigned int num,
void *data,
gfp_t gfp);
int virtqueue_add_inbuf(struct virtqueue *vq,
struct scatterlist sg[], unsigned int num,
void *data,
gfp_t gfp);
int virtqueue_add_sgs(struct virtqueue *vq,
struct scatterlist *sgs[],
unsigned int out_sgs,
unsigned int in_sgs,
void *data,
gfp_t gfp);
void virtqueue_kick(struct virtqueue *vq);
bool virtqueue_kick_prepare(struct virtqueue *vq);
......@@ -64,6 +82,7 @@ unsigned int virtqueue_get_vring_size(struct virtqueue *vq);
* @dev: underlying device.
* @id: the device type identification (used to match it with a driver).
* @config: the configuration ops for this device.
* @vringh_config: configuration ops for host vrings.
* @vqs: the list of virtqueues for this device.
* @features: the features supported by both driver and device.
* @priv: private pointer for the driver's use.
......@@ -73,6 +92,7 @@ struct virtio_device {
struct device dev;
struct virtio_device_id id;
const struct virtio_config_ops *config;
const struct vringh_config_ops *vringh_config;
struct list_head vqs;
/* Note that this is a Linux set_bit-style bitmap. */
unsigned long features[1];
......
include/linux/virtio_caif.h 0 → 100644
View file @ 736a2dd2
/*
* Copyright (C) ST-Ericsson AB 2012
* Author: Sjur Brændeland <sjur.brandeland@stericsson.com>
*
* This header is BSD licensed so
* anyone can use the definitions to implement compatible remote processors
*/
#ifndef VIRTIO_CAIF_H
#define VIRTIO_CAIF_H
#include <linux/types.h>
struct virtio_caif_transf_config {
u16 headroom;
u16 tailroom;
u32 mtu;
u8 reserved[4];
};
struct virtio_caif_config {
struct virtio_caif_transf_config uplink, downlink;
u8 reserved[8];
};
#endif
include/linux/virtio_ring.h
View file @ 736a2dd2
......@@ -4,6 +4,63 @@
#include <linux/irqreturn.h>
#include <uapi/linux/virtio_ring.h>
/*
* Barriers in virtio are tricky. Non-SMP virtio guests can't assume
* they're not on an SMP host system, so they need to assume real
* barriers. Non-SMP virtio hosts could skip the barriers, but does
* anyone care?
*
* For virtio_pci on SMP, we don't need to order with respect to MMIO
* accesses through relaxed memory I/O windows, so smp_mb() et al are
* sufficient.
*
* For using virtio to talk to real devices (eg. other heterogeneous
* CPUs) we do need real barriers. In theory, we could be using both
* kinds of virtio, so it's a runtime decision, and the branch is
* actually quite cheap.
*/
#ifdef CONFIG_SMP
static inline void virtio_mb(bool weak_barriers)
{
if (weak_barriers)
smp_mb();
else
mb();
}
static inline void virtio_rmb(bool weak_barriers)
{
if (weak_barriers)
smp_rmb();
else
rmb();
}
static inline void virtio_wmb(bool weak_barriers)
{
if (weak_barriers)
smp_wmb();
else
wmb();
}
#else
static inline void virtio_mb(bool weak_barriers)
{
mb();
}
static inline void virtio_rmb(bool weak_barriers)
{
rmb();
}
static inline void virtio_wmb(bool weak_barriers)
{
wmb();
}
#endif
struct virtio_device;
struct virtqueue;
......
include/linux/vringh.h 0 → 100644
View file @ 736a2dd2
/*
* Linux host-side vring helpers; for when the kernel needs to access
* someone else's vring.
*
* Copyright IBM Corporation, 2013.
* Parts taken from drivers/vhost/vhost.c Copyright 2009 Red Hat, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Written by: Rusty Russell <rusty@rustcorp.com.au>
*/
#ifndef _LINUX_VRINGH_H
#define _LINUX_VRINGH_H
#include <uapi/linux/virtio_ring.h>
#include <linux/uio.h>
#include <linux/slab.h>
#include <asm/barrier.h>
/* virtio_ring with information needed for host access. */
struct vringh {
/* Guest publishes used event idx (note: we always do). */
bool event_indices;
/* Can we get away with weak barriers? */
bool weak_barriers;
/* Last available index we saw (ie. where we're up to). */
u16 last_avail_idx;
/* Last index we used. */
u16 last_used_idx;
/* How many descriptors we've completed since last need_notify(). */
u32 completed;
/* The vring (note: it may contain user pointers!) */
struct vring vring;
/* The function to call to notify the guest about added buffers */
void (*notify)(struct vringh *);
};
/**
* struct vringh_config_ops - ops for creating a host vring from a virtio driver
* @find_vrhs: find the host vrings and instantiate them
* vdev: the virtio_device
* nhvrs: the number of host vrings to find
* hvrs: on success, includes new host vrings
* callbacks: array of driver callbacks, for each host vring
* include a NULL entry for vqs that do not need a callback
* Returns 0 on success or error status
* @del_vrhs: free the host vrings found by find_vrhs().
*/
struct virtio_device;
typedef void vrh_callback_t(struct virtio_device *, struct vringh *);
struct vringh_config_ops {
int (*find_vrhs)(struct virtio_device *vdev, unsigned nhvrs,
struct vringh *vrhs[], vrh_callback_t *callbacks[]);
void (*del_vrhs)(struct virtio_device *vdev);
};
/* The memory the vring can access, and what offset to apply. */
struct vringh_range {
u64 start, end_incl;
u64 offset;
};
/**
* struct vringh_iov - iovec mangler.
*
* Mangles iovec in place, and restores it.
* Remaining data is iov + i, of used - i elements.
*/
struct vringh_iov {
struct iovec *iov;
size_t consumed; /* Within iov[i] */
unsigned i, used, max_num;
};
/**
* struct vringh_iov - kvec mangler.
*
* Mangles kvec in place, and restores it.
* Remaining data is iov + i, of used - i elements.
*/
struct vringh_kiov {
struct kvec *iov;
size_t consumed; /* Within iov[i] */
unsigned i, used, max_num;
};
/* Flag on max_num to indicate we're kmalloced. */
#define VRINGH_IOV_ALLOCATED 0x8000000
/* Helpers for userspace vrings. */
int vringh_init_user(struct vringh *vrh, u32 features,
unsigned int num, bool weak_barriers,
struct vring_desc __user *desc,
struct vring_avail __user *avail,
struct vring_used __user *used);
static inline void vringh_iov_init(struct vringh_iov *iov,
struct iovec *iovec, unsigned num)
{
iov->used = iov->i = 0;
iov->consumed = 0;
iov->max_num = num;
iov->iov = iovec;
}
static inline void vringh_iov_reset(struct vringh_iov *iov)
{
iov->iov[iov->i].iov_len += iov->consumed;
iov->iov[iov->i].iov_base -= iov->consumed;
iov->consumed = 0;
iov->i = 0;
}
static inline void vringh_iov_cleanup(struct vringh_iov *iov)
{
if (iov->max_num & VRINGH_IOV_ALLOCATED)
kfree(iov->iov);
iov->max_num = iov->used = iov->i = iov->consumed = 0;
iov->iov = NULL;
}
/* Convert a descriptor into iovecs. */
int vringh_getdesc_user(struct vringh *vrh,
struct vringh_iov *riov,
struct vringh_iov *wiov,
bool (*getrange)(struct vringh *vrh,
u64 addr, struct vringh_range *r),
u16 *head);
/* Copy bytes from readable vsg, consuming it (and incrementing wiov->i). */
ssize_t vringh_iov_pull_user(struct vringh_iov *riov, void *dst, size_t len);
/* Copy bytes into writable vsg, consuming it (and incrementing wiov->i). */
ssize_t vringh_iov_push_user(struct vringh_iov *wiov,
const void *src, size_t len);
/* Mark a descriptor as used. */
int vringh_complete_user(struct vringh *vrh, u16 head, u32 len);
int vringh_complete_multi_user(struct vringh *vrh,
const struct vring_used_elem used[],
unsigned num_used);
/* Pretend we've never seen descriptor (for easy error handling). */
void vringh_abandon_user(struct vringh *vrh, unsigned int num);
/* Do we need to fire the eventfd to notify the other side? */
int vringh_need_notify_user(struct vringh *vrh);
bool vringh_notify_enable_user(struct vringh *vrh);
void vringh_notify_disable_user(struct vringh *vrh);
/* Helpers for kernelspace vrings. */
int vringh_init_kern(struct vringh *vrh, u32 features,
unsigned int num, bool weak_barriers,
struct vring_desc *desc,
struct vring_avail *avail,
struct vring_used *used);
static inline void vringh_kiov_init(struct vringh_kiov *kiov,
struct kvec *kvec, unsigned num)
{
kiov->used = kiov->i = 0;
kiov->consumed = 0;
kiov->max_num = num;
kiov->iov = kvec;
}
static inline void vringh_kiov_reset(struct vringh_kiov *kiov)
{
kiov->iov[kiov->i].iov_len += kiov->consumed;
kiov->iov[kiov->i].iov_base -= kiov->consumed;
kiov->consumed = 0;
kiov->i = 0;
}
static inline void vringh_kiov_cleanup(struct vringh_kiov *kiov)
{
if (kiov->max_num & VRINGH_IOV_ALLOCATED)
kfree(kiov->iov);
kiov->max_num = kiov->used = kiov->i = kiov->consumed = 0;
kiov->iov = NULL;
}
int vringh_getdesc_kern(struct vringh *vrh,
struct vringh_kiov *riov,
struct vringh_kiov *wiov,
u16 *head,
gfp_t gfp);
ssize_t vringh_iov_pull_kern(struct vringh_kiov *riov, void *dst, size_t len);
ssize_t vringh_iov_push_kern(struct vringh_kiov *wiov,
const void *src, size_t len);
void vringh_abandon_kern(struct vringh *vrh, unsigned int num);
int vringh_complete_kern(struct vringh *vrh, u16 head, u32 len);
bool vringh_notify_enable_kern(struct vringh *vrh);
void vringh_notify_disable_kern(struct vringh *vrh);
int vringh_need_notify_kern(struct vringh *vrh);
/* Notify the guest about buffers added to the used ring */
static inline void vringh_notify(struct vringh *vrh)
{
if (vrh->notify)
vrh->notify(vrh);
}
#endif /* _LINUX_VRINGH_H */
include/uapi/linux/virtio_balloon.h
View file @ 736a2dd2
......@@ -52,8 +52,8 @@ struct virtio_balloon_config
#define VIRTIO_BALLOON_S_NR 6
struct virtio_balloon_stat {
u16 tag;
u64 val;
__u16 tag;
__u64 val;
} __attribute__((packed));
#endif /* _LINUX_VIRTIO_BALLOON_H */
include/uapi/linux/virtio_ids.h
View file @ 736a2dd2
......@@ -38,5 +38,6 @@
#define VIRTIO_ID_SCSI 8 /* virtio scsi */
#define VIRTIO_ID_9P 9 /* 9p virtio console */
#define VIRTIO_ID_RPROC_SERIAL 11 /* virtio remoteproc serial link */
#define VIRTIO_ID_CAIF 12 /* Virtio caif */
#endif /* _LINUX_VIRTIO_IDS_H */
net/9p/trans_virtio.c
View file @ 736a2dd2
......@@ -194,11 +194,14 @@ static int pack_sg_list(struct scatterlist *sg, int start,
if (s > count)
s = count;
BUG_ON(index > limit);
/* Make sure we don't terminate early. */
sg_unmark_end(&sg[index]);
sg_set_buf(&sg[index++], data, s);
count -= s;
data += s;
}
if (index-start)
sg_mark_end(&sg[index - 1]);
return index-start;
}
......@@ -236,12 +239,17 @@ pack_sg_list_p(struct scatterlist *sg, int start, int limit,
s = rest_of_page(data);
if (s > count)
s = count;
/* Make sure we don't terminate early. */
sg_unmark_end(&sg[index]);
sg_set_page(&sg[index++], pdata[i++], s, data_off);
data_off = 0;
data += s;
count -= s;
nr_pages--;
}
if (index-start)
sg_mark_end(&sg[index - 1]);
return index - start;
}
......@@ -256,9 +264,10 @@ static int
p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
{
int err;
int in, out;
int in, out, out_sgs, in_sgs;
unsigned long flags;
struct virtio_chan *chan = client->trans;
struct scatterlist *sgs[2];
p9_debug(P9_DEBUG_TRANS, "9p debug: virtio request\n");
......@@ -266,14 +275,19 @@ p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
req_retry:
spin_lock_irqsave(&chan->lock, flags);
out_sgs = in_sgs = 0;
/* Handle out VirtIO ring buffers */
out = pack_sg_list(chan->sg, 0,
VIRTQUEUE_NUM, req->tc->sdata, req->tc->size);
if (out)
sgs[out_sgs++] = chan->sg;
in = pack_sg_list(chan->sg, out,
VIRTQUEUE_NUM, req->rc->sdata, req->rc->capacity);
if (in)
sgs[out_sgs + in_sgs++] = chan->sg + out;
err = virtqueue_add_buf(chan->vq, chan->sg, out, in, req->tc,
err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc,
GFP_ATOMIC);
if (err < 0) {
if (err == -ENOSPC) {
......@@ -289,7 +303,7 @@ p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
} else {
spin_unlock_irqrestore(&chan->lock, flags);
p9_debug(P9_DEBUG_TRANS,
"virtio rpc add_buf returned failure\n");
"virtio rpc add_sgs returned failure\n");
return -EIO;
}
}
......@@ -351,11 +365,12 @@ p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
char *uidata, char *uodata, int inlen,
int outlen, int in_hdr_len, int kern_buf)
{
int in, out, err;
int in, out, err, out_sgs, in_sgs;
unsigned long flags;
int in_nr_pages = 0, out_nr_pages = 0;
struct page **in_pages = NULL, **out_pages = NULL;
struct virtio_chan *chan = client->trans;
struct scatterlist *sgs[4];
p9_debug(P9_DEBUG_TRANS, "virtio request\n");
......@@ -396,13 +411,22 @@ p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
req->status = REQ_STATUS_SENT;
req_retry_pinned:
spin_lock_irqsave(&chan->lock, flags);
out_sgs = in_sgs = 0;
/* out data */
out = pack_sg_list(chan->sg, 0,
VIRTQUEUE_NUM, req->tc->sdata, req->tc->size);
if (out_pages)
if (out)
sgs[out_sgs++] = chan->sg;
if (out_pages) {
sgs[out_sgs++] = chan->sg + out;
out += pack_sg_list_p(chan->sg, out, VIRTQUEUE_NUM,
out_pages, out_nr_pages, uodata, outlen);
}
/*
* Take care of in data
* For example TREAD have 11.
......@@ -412,11 +436,17 @@ p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
*/
in = pack_sg_list(chan->sg, out,
VIRTQUEUE_NUM, req->rc->sdata, in_hdr_len);
if (in_pages)
if (in)
sgs[out_sgs + in_sgs++] = chan->sg + out;
if (in_pages) {
sgs[out_sgs + in_sgs++] = chan->sg + out + in;
in += pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM,
in_pages, in_nr_pages, uidata, inlen);
}
err = virtqueue_add_buf(chan->vq, chan->sg, out, in, req->tc,
BUG_ON(out_sgs + in_sgs > ARRAY_SIZE(sgs));
err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc,
GFP_ATOMIC);
if (err < 0) {
if (err == -ENOSPC) {
......@@ -432,7 +462,7 @@ p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
} else {
spin_unlock_irqrestore(&chan->lock, flags);
p9_debug(P9_DEBUG_TRANS,
"virtio rpc add_buf returned failure\n");
"virtio rpc add_sgs returned failure\n");
err = -EIO;
goto err_out;
}
......
tools/lguest/lguest.txt
View file @ 736a2dd2
......@@ -70,7 +70,7 @@ Running Lguest:
- Run an lguest as root:
Documentation/virtual/lguest/lguest 64 vmlinux --tunnet=192.168.19.1 \
tools/lguest/lguest 64 vmlinux --tunnet=192.168.19.1 \
--block=rootfile root=/dev/vda
Explanation:
......
tools/virtio/Makefile
View file @ 736a2dd2
all: test mod
test: virtio_test
test: virtio_test vringh_test
virtio_test: virtio_ring.o virtio_test.o
CFLAGS += -g -O2 -Wall -I. -I ../../usr/include/ -Wno-pointer-sign -fno-strict-overflow -MMD
vpath %.c ../../drivers/virtio
vringh_test: vringh_test.o vringh.o virtio_ring.o
CFLAGS += -g -O2 -Wall -I. -I ../../usr/include/ -Wno-pointer-sign -fno-strict-overflow -fno-strict-aliasing -fno-common -MMD -U_FORTIFY_SOURCE
vpath %.c ../../drivers/virtio ../../drivers/vhost
mod:
${MAKE} -C `pwd`/../.. M=`pwd`/vhost_test
.PHONY: all test mod clean
clean:
${RM} *.o vhost_test/*.o vhost_test/.*.cmd \
${RM} *.o vringh_test virtio_test vhost_test/*.o vhost_test/.*.cmd \
vhost_test/Module.symvers vhost_test/modules.order *.d
-include *.d
tools/virtio/asm/barrier.h 0 → 100644
View file @ 736a2dd2
#if defined(__i386__) || defined(__x86_64__)
#define barrier() asm volatile("" ::: "memory")
#define mb() __sync_synchronize()
#define smp_mb() mb()
# define smp_rmb() barrier()
# define smp_wmb() barrier()
/* Weak barriers should be used. If not - it's a bug */
# define rmb() abort()
# define wmb() abort()
#else
#error Please fill in barrier macros
#endif
tools/virtio/linux/bug.h 0 → 100644
View file @ 736a2dd2
#ifndef BUG_H
#define BUG_H
#define BUG_ON(__BUG_ON_cond) assert(!(__BUG_ON_cond))
#define BUILD_BUG_ON(x)
#define BUG() abort()
#endif /* BUG_H */
tools/virtio/linux/err.h 0 → 100644
View file @ 736a2dd2
#ifndef ERR_H
#define ERR_H
#define MAX_ERRNO 4095
#define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO)
static inline void * __must_check ERR_PTR(long error)
{
return (void *) error;
}
static inline long __must_check PTR_ERR(const void *ptr)
{
return (long) ptr;
}
static inline long __must_check IS_ERR(const void *ptr)
{
return IS_ERR_VALUE((unsigned long)ptr);
}
static inline long __must_check IS_ERR_OR_NULL(const void *ptr)
{
return !ptr || IS_ERR_VALUE((unsigned long)ptr);
}
#endif /* ERR_H */
tools/virtio/linux/export.h 0 → 100644
View file @ 736a2dd2
#define EXPORT_SYMBOL(sym)
#define EXPORT_SYMBOL_GPL(sym)
#define EXPORT_SYMBOL_GPL_FUTURE(sym)
#define EXPORT_UNUSED_SYMBOL(sym)
#define EXPORT_UNUSED_SYMBOL_GPL(sym)
tools/virtio/linux/irqreturn.h 0 → 100644
View file @ 736a2dd2
#include "../../../include/linux/irqreturn.h"
tools/virtio/linux/kernel.h 0 → 100644
View file @ 736a2dd2
#ifndef KERNEL_H
#define KERNEL_H
#include <stdbool.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <stdarg.h>
#include <linux/types.h>
#include <linux/printk.h>
#include <linux/bug.h>
#include <errno.h>
#include <unistd.h>
#include <asm/barrier.h>
#define CONFIG_SMP
#define PAGE_SIZE getpagesize()
#define PAGE_MASK (~(PAGE_SIZE-1))
typedef unsigned long long dma_addr_t;
typedef size_t __kernel_size_t;
struct page {
unsigned long long dummy;
};
/* Physical == Virtual */
#define virt_to_phys(p) ((unsigned long)p)
#define phys_to_virt(a) ((void *)(unsigned long)(a))
/* Page address: Virtual / 4K */
#define page_to_phys(p) ((dma_addr_t)(unsigned long)(p))
#define virt_to_page(p) ((struct page *)((unsigned long)p & PAGE_MASK))
#define offset_in_page(p) (((unsigned long)p) % PAGE_SIZE)
#define __printf(a,b) __attribute__((format(printf,a,b)))
typedef enum {
GFP_KERNEL,
GFP_ATOMIC,
__GFP_HIGHMEM,
__GFP_HIGH
} gfp_t;
#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
extern void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
static inline void *kmalloc(size_t s, gfp_t gfp)
{
if (__kmalloc_fake)
return __kmalloc_fake;
return malloc(s);
}
static inline void kfree(void *p)
{
if (p >= __kfree_ignore_start && p < __kfree_ignore_end)
return;
free(p);
}
static inline void *krealloc(void *p, size_t s, gfp_t gfp)
{
return realloc(p, s);
}
static inline unsigned long __get_free_page(gfp_t gfp)
{
void *p;
posix_memalign(&p, PAGE_SIZE, PAGE_SIZE);
return (unsigned long)p;
}
static inline void free_page(unsigned long addr)
{
free((void *)addr);
}
#define container_of(ptr, type, member) ({ \
const typeof( ((type *)0)->member ) *__mptr = (ptr); \
(type *)( (char *)__mptr - offsetof(type,member) );})
#define uninitialized_var(x) x = x
# ifndef likely
# define likely(x) (__builtin_expect(!!(x), 1))
# endif
# ifndef unlikely
# define unlikely(x) (__builtin_expect(!!(x), 0))
# endif
#define pr_err(format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#ifdef DEBUG
#define pr_debug(format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#else
#define pr_debug(format, ...) do {} while (0)
#endif
#define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#define min(x, y) ({ \
typeof(x) _min1 = (x); \
typeof(y) _min2 = (y); \
(void) (&_min1 == &_min2); \
_min1 < _min2 ? _min1 : _min2; })
#endif /* KERNEL_H */
tools/virtio/linux/printk.h 0 → 100644
View file @ 736a2dd2
#include "../../../include/linux/kern_levels.h"
#define printk printf
#define vprintk vprintf
tools/virtio/linux/ratelimit.h 0 → 100644
View file @ 736a2dd2
#define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init) int name = 0
#define __ratelimit(x) (*(x))
tools/virtio/linux/scatterlist.h 0 → 100644
View file @ 736a2dd2
#ifndef SCATTERLIST_H
#define SCATTERLIST_H
#include <linux/kernel.h>
struct scatterlist {
unsigned long page_link;
unsigned int offset;
unsigned int length;
dma_addr_t dma_address;
};
/* Scatterlist helpers, stolen from linux/scatterlist.h */
#define sg_is_chain(sg) ((sg)->page_link & 0x01)
#define sg_is_last(sg) ((sg)->page_link & 0x02)
#define sg_chain_ptr(sg) \
((struct scatterlist *) ((sg)->page_link & ~0x03))
/**
* sg_assign_page - Assign a given page to an SG entry
* @sg: SG entry
* @page: The page
*
* Description:
* Assign page to sg entry. Also see sg_set_page(), the most commonly used
* variant.
*
**/
static inline void sg_assign_page(struct scatterlist *sg, struct page *page)
{
unsigned long page_link = sg->page_link & 0x3;
/*
* In order for the low bit stealing approach to work, pages
* must be aligned at a 32-bit boundary as a minimum.
*/
BUG_ON((unsigned long) page & 0x03);
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
BUG_ON(sg_is_chain(sg));
#endif
sg->page_link = page_link | (unsigned long) page;
}
/**
* sg_set_page - Set sg entry to point at given page
* @sg: SG entry
* @page: The page
* @len: Length of data
* @offset: Offset into page
*
* Description:
* Use this function to set an sg entry pointing at a page, never assign
* the page directly. We encode sg table information in the lower bits
* of the page pointer. See sg_page() for looking up the page belonging
* to an sg entry.
*
**/
static inline void sg_set_page(struct scatterlist *sg, struct page *page,
unsigned int len, unsigned int offset)
{
sg_assign_page(sg, page);
sg->offset = offset;
sg->length = len;
}
static inline struct page *sg_page(struct scatterlist *sg)
{
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
BUG_ON(sg_is_chain(sg));
#endif
return (struct page *)((sg)->page_link & ~0x3);
}
/*
* Loop over each sg element, following the pointer to a new list if necessary
*/
#define for_each_sg(sglist, sg, nr, __i) \
for (__i = 0, sg = (sglist); __i < (nr); __i++, sg = sg_next(sg))
/**
* sg_chain - Chain two sglists together
* @prv: First scatterlist
* @prv_nents: Number of entries in prv
* @sgl: Second scatterlist
*
* Description:
* Links @prv@ and @sgl@ together, to form a longer scatterlist.
*
**/
static inline void sg_chain(struct scatterlist *prv, unsigned int prv_nents,
struct scatterlist *sgl)
{
/*
* offset and length are unused for chain entry. Clear them.
*/
prv[prv_nents - 1].offset = 0;
prv[prv_nents - 1].length = 0;
/*
* Set lowest bit to indicate a link pointer, and make sure to clear
* the termination bit if it happens to be set.
*/
prv[prv_nents - 1].page_link = ((unsigned long) sgl | 0x01) & ~0x02;
}
/**
* sg_mark_end - Mark the end of the scatterlist
* @sg: SG entryScatterlist
*
* Description:
* Marks the passed in sg entry as the termination point for the sg
* table. A call to sg_next() on this entry will return NULL.
*
**/
static inline void sg_mark_end(struct scatterlist *sg)
{
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
#endif
/*
* Set termination bit, clear potential chain bit
*/
sg->page_link |= 0x02;
sg->page_link &= ~0x01;
}
/**
* sg_unmark_end - Undo setting the end of the scatterlist
* @sg: SG entryScatterlist
*
* Description:
* Removes the termination marker from the given entry of the scatterlist.
*
**/
static inline void sg_unmark_end(struct scatterlist *sg)
{
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
#endif
sg->page_link &= ~0x02;
}
static inline struct scatterlist *sg_next(struct scatterlist *sg)
{
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
#endif
if (sg_is_last(sg))
return NULL;
sg++;
if (unlikely(sg_is_chain(sg)))
sg = sg_chain_ptr(sg);
return sg;
}
static inline void sg_init_table(struct scatterlist *sgl, unsigned int nents)
{
memset(sgl, 0, sizeof(*sgl) * nents);
#ifdef CONFIG_DEBUG_SG
{
unsigned int i;
for (i = 0; i < nents; i++)
sgl[i].sg_magic = SG_MAGIC;
}
#endif
sg_mark_end(&sgl[nents - 1]);
}
static inline dma_addr_t sg_phys(struct scatterlist *sg)
{
return page_to_phys(sg_page(sg)) + sg->offset;
}
static inline void sg_set_buf(struct scatterlist *sg, const void *buf,
unsigned int buflen)
{
sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
}
static inline void sg_init_one(struct scatterlist *sg,
const void *buf, unsigned int buflen)
{
sg_init_table(sg, 1);
sg_set_buf(sg, buf, buflen);
}
#endif /* SCATTERLIST_H */
tools/virtio/linux/types.h 0 → 100644
View file @ 736a2dd2
#ifndef TYPES_H
#define TYPES_H
#include <stdint.h>
#define __force
#define __user
#define __must_check
#define __cold
typedef uint64_t u64;
typedef int64_t s64;
typedef uint32_t u32;
typedef int32_t s32;
typedef uint16_t u16;
typedef int16_t s16;
typedef uint8_t u8;
typedef int8_t s8;
typedef uint64_t __u64;
typedef int64_t __s64;
typedef uint32_t __u32;
typedef int32_t __s32;
typedef uint16_t __u16;
typedef int16_t __s16;
typedef uint8_t __u8;
typedef int8_t __s8;
#endif /* TYPES_H */
tools/virtio/linux/uaccess.h 0 → 100644
View file @ 736a2dd2
#ifndef UACCESS_H
#define UACCESS_H
extern void *__user_addr_min, *__user_addr_max;
#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))
static inline void __chk_user_ptr(const volatile void *p, size_t size)
{
assert(p >= __user_addr_min && p + size <= __user_addr_max);
}
#define put_user(x, ptr) \
({ \
typeof(ptr) __pu_ptr = (ptr); \
__chk_user_ptr(__pu_ptr, sizeof(*__pu_ptr)); \
ACCESS_ONCE(*(__pu_ptr)) = x; \
0; \
})
#define get_user(x, ptr) \
({ \
typeof(ptr) __pu_ptr = (ptr); \
__chk_user_ptr(__pu_ptr, sizeof(*__pu_ptr)); \
x = ACCESS_ONCE(*(__pu_ptr)); \
0; \
})
static void volatile_memcpy(volatile char *to, const volatile char *from,
unsigned long n)
{
while (n--)
*(to++) = *(from++);
}
static inline int copy_from_user(void *to, const void __user volatile *from,
unsigned long n)
{
__chk_user_ptr(from, n);
volatile_memcpy(to, from, n);
return 0;
}
static inline int copy_to_user(void __user volatile *to, const void *from,
unsigned long n)
{
__chk_user_ptr(to, n);
volatile_memcpy(to, from, n);
return 0;
}
#endif /* UACCESS_H */
tools/virtio/linux/uio.h 0 → 100644
View file @ 736a2dd2
#include <linux/kernel.h>
#include "../../../include/linux/uio.h"
tools/virtio/linux/virtio.h
View file @ 736a2dd2
#ifndef LINUX_VIRTIO_H
#define LINUX_VIRTIO_H
#include <stdbool.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <linux/types.h>
#include <errno.h>
typedef unsigned long long dma_addr_t;
struct scatterlist {
unsigned long page_link;
unsigned int offset;
unsigned int length;
dma_addr_t dma_address;
};
struct page {
unsigned long long dummy;
};
#define BUG_ON(__BUG_ON_cond) assert(!(__BUG_ON_cond))
/* Physical == Virtual */
#define virt_to_phys(p) ((unsigned long)p)
#define phys_to_virt(a) ((void *)(unsigned long)(a))
/* Page address: Virtual / 4K */
#define virt_to_page(p) ((struct page*)((virt_to_phys(p) / 4096) * \
sizeof(struct page)))
#define offset_in_page(p) (((unsigned long)p) % 4096)
#define sg_phys(sg) ((sg->page_link & ~0x3) / sizeof(struct page) * 4096 + \
sg->offset)
static inline void sg_mark_end(struct scatterlist *sg)
{
/*
* Set termination bit, clear potential chain bit
*/
sg->page_link |= 0x02;
sg->page_link &= ~0x01;
}
static inline void sg_init_table(struct scatterlist *sgl, unsigned int nents)
{
memset(sgl, 0, sizeof(*sgl) * nents);
sg_mark_end(&sgl[nents - 1]);
}
static inline void sg_assign_page(struct scatterlist *sg, struct page *page)
{
unsigned long page_link = sg->page_link & 0x3;
/*
* In order for the low bit stealing approach to work, pages
* must be aligned at a 32-bit boundary as a minimum.
*/
BUG_ON((unsigned long) page & 0x03);
sg->page_link = page_link | (unsigned long) page;
}
static inline void sg_set_page(struct scatterlist *sg, struct page *page,
unsigned int len, unsigned int offset)
{
sg_assign_page(sg, page);
sg->offset = offset;
sg->length = len;
}
static inline void sg_set_buf(struct scatterlist *sg, const void *buf,
unsigned int buflen)
{
sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
}
static inline void sg_init_one(struct scatterlist *sg, const void *buf, unsigned int buflen)
{
sg_init_table(sg, 1);
sg_set_buf(sg, buf, buflen);
}
typedef __u16 u16;
typedef enum {
GFP_KERNEL,
GFP_ATOMIC,
} gfp_t;
typedef enum {
IRQ_NONE,
IRQ_HANDLED
} irqreturn_t;
static inline void *kmalloc(size_t s, gfp_t gfp)
{
return malloc(s);
}
static inline void kfree(void *p)
{
free(p);
}
#define container_of(ptr, type, member) ({ \
const typeof( ((type *)0)->member ) *__mptr = (ptr); \
(type *)( (char *)__mptr - offsetof(type,member) );})
#define uninitialized_var(x) x = x
# ifndef likely
# define likely(x) (__builtin_expect(!!(x), 1))
# endif
# ifndef unlikely
# define unlikely(x) (__builtin_expect(!!(x), 0))
# endif
#define pr_err(format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#ifdef DEBUG
#define pr_debug(format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#else
#define pr_debug(format, ...) do {} while (0)
#endif
#define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#include <linux/scatterlist.h>
#include <linux/kernel.h>
/* TODO: empty stubs for now. Broken but enough for virtio_ring.c */
#define list_add_tail(a, b) do {} while (0)
......@@ -131,6 +11,7 @@ static inline void kfree(void *p)
#define BITS_PER_BYTE 8
#define BITS_PER_LONG (sizeof(long) * BITS_PER_BYTE)
#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
/* TODO: Not atomic as it should be:
* we don't use this for anything important. */
static inline void clear_bit(int nr, volatile unsigned long *addr)
......@@ -145,10 +26,6 @@ static inline int test_bit(int nr, const volatile unsigned long *addr)
{
return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
}
/* The only feature we care to support */
#define virtio_has_feature(dev, feature) \
test_bit((feature), (dev)->features)
/* end of stubs */
struct virtio_device {
......@@ -163,39 +40,32 @@ struct virtqueue {
void (*callback)(struct virtqueue *vq);
const char *name;
struct virtio_device *vdev;
unsigned int index;
unsigned int num_free;
void *priv;
};
#define EXPORT_SYMBOL_GPL(__EXPORT_SYMBOL_GPL_name) \
void __EXPORT_SYMBOL_GPL##__EXPORT_SYMBOL_GPL_name() { \
}
#define MODULE_LICENSE(__MODULE_LICENSE_value) \
const char *__MODULE_LICENSE_name = __MODULE_LICENSE_value
#define CONFIG_SMP
#if defined(__i386__) || defined(__x86_64__)
#define barrier() asm volatile("" ::: "memory")
#define mb() __sync_synchronize()
#define smp_mb() mb()
# define smp_rmb() barrier()
# define smp_wmb() barrier()
/* Weak barriers should be used. If not - it's a bug */
# define rmb() abort()
# define wmb() abort()
#else
#error Please fill in barrier macros
#endif
/* Interfaces exported by virtio_ring. */
int virtqueue_add_buf(struct virtqueue *vq,
struct scatterlist sg[],
unsigned int out_num,
unsigned int in_num,
int virtqueue_add_sgs(struct virtqueue *vq,
struct scatterlist *sgs[],
unsigned int out_sgs,
unsigned int in_sgs,
void *data,
gfp_t gfp);
int virtqueue_add_outbuf(struct virtqueue *vq,
struct scatterlist sg[], unsigned int num,
void *data,
gfp_t gfp);
int virtqueue_add_inbuf(struct virtqueue *vq,
struct scatterlist sg[], unsigned int num,
void *data,
gfp_t gfp);
void virtqueue_kick(struct virtqueue *vq);
void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
......@@ -206,7 +76,8 @@ bool virtqueue_enable_cb(struct virtqueue *vq);
bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
void *virtqueue_detach_unused_buf(struct virtqueue *vq);
struct virtqueue *vring_new_virtqueue(unsigned int num,
struct virtqueue *vring_new_virtqueue(unsigned int index,
unsigned int num,
unsigned int vring_align,
struct virtio_device *vdev,
bool weak_barriers,
......
tools/virtio/linux/virtio_config.h 0 → 100644
View file @ 736a2dd2
#define VIRTIO_TRANSPORT_F_START 28
#define VIRTIO_TRANSPORT_F_END 32
#define virtio_has_feature(dev, feature) \
test_bit((feature), (dev)->features)
tools/virtio/linux/virtio_ring.h 0 → 100644
View file @ 736a2dd2
#include "../../../include/linux/virtio_ring.h"
tools/virtio/linux/vringh.h 0 → 100644
View file @ 736a2dd2
#include "../../../include/linux/vringh.h"
tools/virtio/uapi/linux/virtio_config.h 0 → 100644
View file @ 736a2dd2
#include "../../../../include/uapi/linux/virtio_config.h"
tools/virtio/uapi/linux/virtio_ring.h 0 → 100644
View file @ 736a2dd2
#ifndef VIRTIO_RING_H
#define VIRTIO_RING_H
#include "../../../../include/uapi/linux/virtio_ring.h"
#endif /* VIRTIO_RING_H */
tools/virtio/virtio_test.c
View file @ 736a2dd2
......@@ -10,11 +10,15 @@
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <stdbool.h>
#include <linux/vhost.h>
#include <linux/virtio.h>
#include <linux/virtio_ring.h>
#include "../../drivers/vhost/test.h"
/* Unused */
void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
struct vq_info {
int kick;
int call;
......@@ -92,7 +96,8 @@ static void vq_info_add(struct vdev_info *dev, int num)
assert(r >= 0);
memset(info->ring, 0, vring_size(num, 4096));
vring_init(&info->vring, num, info->ring, 4096);
info->vq = vring_new_virtqueue(info->vring.num, 4096, &dev->vdev,
info->vq = vring_new_virtqueue(info->idx,
info->vring.num, 4096, &dev->vdev,
true, info->ring,
vq_notify, vq_callback, "test");
assert(info->vq);
......@@ -161,9 +166,9 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
do {
if (started < bufs) {
sg_init_one(&sl, dev->buf, dev->buf_size);
r = virtqueue_add_buf(vq->vq, &sl, 1, 0,
dev->buf + started,
GFP_ATOMIC);
r = virtqueue_add_outbuf(vq->vq, &sl, 1,
dev->buf + started,
GFP_ATOMIC);
if (likely(r == 0)) {
++started;
virtqueue_kick(vq->vq);
......
tools/virtio/vringh_test.c 0 → 100644
View file @ 736a2dd2
/* Simple test of virtio code, entirely in userpsace. */
#define _GNU_SOURCE
#include <sched.h>
#include <err.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/virtio.h>
#include <linux/vringh.h>
#include <linux/virtio_ring.h>
#include <linux/uaccess.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include <fcntl.h>
#define USER_MEM (1024*1024)
void *__user_addr_min, *__user_addr_max;
void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
static u64 user_addr_offset;
#define RINGSIZE 256
#define ALIGN 4096
static void never_notify_host(struct virtqueue *vq)
{
abort();
}
static void never_callback_guest(struct virtqueue *vq)
{
abort();
}
static bool getrange_iov(struct vringh *vrh, u64 addr, struct vringh_range *r)
{
if (addr < (u64)(unsigned long)__user_addr_min - user_addr_offset)
return false;
if (addr >= (u64)(unsigned long)__user_addr_max - user_addr_offset)
return false;
r->start = (u64)(unsigned long)__user_addr_min - user_addr_offset;
r->end_incl = (u64)(unsigned long)__user_addr_max - 1 - user_addr_offset;
r->offset = user_addr_offset;
return true;
}
/* We return single byte ranges. */
static bool getrange_slow(struct vringh *vrh, u64 addr, struct vringh_range *r)
{
if (addr < (u64)(unsigned long)__user_addr_min - user_addr_offset)
return false;
if (addr >= (u64)(unsigned long)__user_addr_max - user_addr_offset)
return false;
r->start = addr;
r->end_incl = r->start;
r->offset = user_addr_offset;
return true;
}
struct guest_virtio_device {
struct virtio_device vdev;
int to_host_fd;
unsigned long notifies;
};
static void parallel_notify_host(struct virtqueue *vq)
{
struct guest_virtio_device *gvdev;
gvdev = container_of(vq->vdev, struct guest_virtio_device, vdev);
write(gvdev->to_host_fd, "", 1);
gvdev->notifies++;
}
static void no_notify_host(struct virtqueue *vq)
{
}
#define NUM_XFERS (10000000)
/* We aim for two "distant" cpus. */
static void find_cpus(unsigned int *first, unsigned int *last)
{
unsigned int i;
*first = -1U;
*last = 0;
for (i = 0; i < 4096; i++) {
cpu_set_t set;
CPU_ZERO(&set);
CPU_SET(i, &set);
if (sched_setaffinity(getpid(), sizeof(set), &set) == 0) {
if (i < *first)
*first = i;
if (i > *last)
*last = i;
}
}
}
/* Opencoded version for fast mode */
static inline int vringh_get_head(struct vringh *vrh, u16 *head)
{
u16 avail_idx, i;
int err;
err = get_user(avail_idx, &vrh->vring.avail->idx);
if (err)
return err;
if (vrh->last_avail_idx == avail_idx)
return 0;
/* Only get avail ring entries after they have been exposed by guest. */
virtio_rmb(vrh->weak_barriers);
i = vrh->last_avail_idx & (vrh->vring.num - 1);
err = get_user(*head, &vrh->vring.avail->ring[i]);
if (err)
return err;
vrh->last_avail_idx++;
return 1;
}
static int parallel_test(unsigned long features,
bool (*getrange)(struct vringh *vrh,
u64 addr, struct vringh_range *r),
bool fast_vringh)
{
void *host_map, *guest_map;
int fd, mapsize, to_guest[2], to_host[2];
unsigned long xfers = 0, notifies = 0, receives = 0;
unsigned int first_cpu, last_cpu;
cpu_set_t cpu_set;
char buf[128];
/* Create real file to mmap. */
fd = open("/tmp/vringh_test-file", O_RDWR|O_CREAT|O_TRUNC, 0600);
if (fd < 0)
err(1, "Opening /tmp/vringh_test-file");
/* Extra room at the end for some data, and indirects */
mapsize = vring_size(RINGSIZE, ALIGN)
+ RINGSIZE * 2 * sizeof(int)
+ RINGSIZE * 6 * sizeof(struct vring_desc);
mapsize = (mapsize + getpagesize() - 1) & ~(getpagesize() - 1);
ftruncate(fd, mapsize);
/* Parent and child use separate addresses, to check our mapping logic! */
host_map = mmap(NULL, mapsize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
guest_map = mmap(NULL, mapsize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
pipe(to_guest);
pipe(to_host);
CPU_ZERO(&cpu_set);
find_cpus(&first_cpu, &last_cpu);
printf("Using CPUS %u and %u\n", first_cpu, last_cpu);
fflush(stdout);
if (fork() != 0) {
struct vringh vrh;
int status, err, rlen = 0;
char rbuf[5];
/* We are the host: never access guest addresses! */
munmap(guest_map, mapsize);
__user_addr_min = host_map;
__user_addr_max = __user_addr_min + mapsize;
user_addr_offset = host_map - guest_map;
assert(user_addr_offset);
close(to_guest[0]);
close(to_host[1]);
vring_init(&vrh.vring, RINGSIZE, host_map, ALIGN);
vringh_init_user(&vrh, features, RINGSIZE, true,
vrh.vring.desc, vrh.vring.avail, vrh.vring.used);
CPU_SET(first_cpu, &cpu_set);
if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set))
errx(1, "Could not set affinity to cpu %u", first_cpu);
while (xfers < NUM_XFERS) {
struct iovec host_riov[2], host_wiov[2];
struct vringh_iov riov, wiov;
u16 head, written;
if (fast_vringh) {
for (;;) {
err = vringh_get_head(&vrh, &head);
if (err != 0)
break;
err = vringh_need_notify_user(&vrh);
if (err < 0)
errx(1, "vringh_need_notify_user: %i",
err);
if (err) {
write(to_guest[1], "", 1);
notifies++;
}
}
if (err != 1)
errx(1, "vringh_get_head");
written = 0;
goto complete;
} else {
vringh_iov_init(&riov,
host_riov,
ARRAY_SIZE(host_riov));
vringh_iov_init(&wiov,
host_wiov,
ARRAY_SIZE(host_wiov));
err = vringh_getdesc_user(&vrh, &riov, &wiov,
getrange, &head);
}
if (err == 0) {
err = vringh_need_notify_user(&vrh);
if (err < 0)
errx(1, "vringh_need_notify_user: %i",
err);
if (err) {
write(to_guest[1], "", 1);
notifies++;
}
if (!vringh_notify_enable_user(&vrh))
continue;
/* Swallow all notifies at once. */
if (read(to_host[0], buf, sizeof(buf)) < 1)
break;
vringh_notify_disable_user(&vrh);
receives++;
continue;
}
if (err != 1)
errx(1, "vringh_getdesc_user: %i", err);
/* We simply copy bytes. */
if (riov.used) {
rlen = vringh_iov_pull_user(&riov, rbuf,
sizeof(rbuf));
if (rlen != 4)
errx(1, "vringh_iov_pull_user: %i",
rlen);
assert(riov.i == riov.used);
written = 0;
} else {
err = vringh_iov_push_user(&wiov, rbuf, rlen);
if (err != rlen)
errx(1, "vringh_iov_push_user: %i",
err);
assert(wiov.i == wiov.used);
written = err;
}
complete:
xfers++;
err = vringh_complete_user(&vrh, head, written);
if (err != 0)
errx(1, "vringh_complete_user: %i", err);
}
err = vringh_need_notify_user(&vrh);
if (err < 0)
errx(1, "vringh_need_notify_user: %i", err);
if (err) {
write(to_guest[1], "", 1);
notifies++;
}
wait(&status);
if (!WIFEXITED(status))
errx(1, "Child died with signal %i?", WTERMSIG(status));
if (WEXITSTATUS(status) != 0)
errx(1, "Child exited %i?", WEXITSTATUS(status));
printf("Host: notified %lu, pinged %lu\n", notifies, receives);
return 0;
} else {
struct guest_virtio_device gvdev;
struct virtqueue *vq;
unsigned int *data;
struct vring_desc *indirects;
unsigned int finished = 0;
/* We pass sg[]s pointing into here, but we need RINGSIZE+1 */
data = guest_map + vring_size(RINGSIZE, ALIGN);
indirects = (void *)data + (RINGSIZE + 1) * 2 * sizeof(int);
/* We are the guest. */
munmap(host_map, mapsize);
close(to_guest[1]);
close(to_host[0]);
gvdev.vdev.features[0] = features;
gvdev.to_host_fd = to_host[1];
gvdev.notifies = 0;
CPU_SET(first_cpu, &cpu_set);
if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set))
err(1, "Could not set affinity to cpu %u", first_cpu);
vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &gvdev.vdev, true,
guest_map, fast_vringh ? no_notify_host
: parallel_notify_host,
never_callback_guest, "guest vq");
/* Don't kfree indirects. */
__kfree_ignore_start = indirects;
__kfree_ignore_end = indirects + RINGSIZE * 6;
while (xfers < NUM_XFERS) {
struct scatterlist sg[4];
unsigned int num_sg, len;
int *dbuf, err;
bool output = !(xfers % 2);
/* Consume bufs. */
while ((dbuf = virtqueue_get_buf(vq, &len)) != NULL) {
if (len == 4)
assert(*dbuf == finished - 1);
else if (!fast_vringh)
assert(*dbuf == finished);
finished++;
}
/* Produce a buffer. */
dbuf = data + (xfers % (RINGSIZE + 1));
if (output)
*dbuf = xfers;
else
*dbuf = -1;
switch ((xfers / sizeof(*dbuf)) % 4) {
case 0:
/* Nasty three-element sg list. */
sg_init_table(sg, num_sg = 3);
sg_set_buf(&sg[0], (void *)dbuf, 1);
sg_set_buf(&sg[1], (void *)dbuf + 1, 2);
sg_set_buf(&sg[2], (void *)dbuf + 3, 1);
break;
case 1:
sg_init_table(sg, num_sg = 2);
sg_set_buf(&sg[0], (void *)dbuf, 1);
sg_set_buf(&sg[1], (void *)dbuf + 1, 3);
break;
case 2:
sg_init_table(sg, num_sg = 1);
sg_set_buf(&sg[0], (void *)dbuf, 4);
break;
case 3:
sg_init_table(sg, num_sg = 4);
sg_set_buf(&sg[0], (void *)dbuf, 1);
sg_set_buf(&sg[1], (void *)dbuf + 1, 1);
sg_set_buf(&sg[2], (void *)dbuf + 2, 1);
sg_set_buf(&sg[3], (void *)dbuf + 3, 1);
break;
}
/* May allocate an indirect, so force it to allocate
* user addr */
__kmalloc_fake = indirects + (xfers % RINGSIZE) * 4;
if (output)
err = virtqueue_add_outbuf(vq, sg, num_sg, dbuf,
GFP_KERNEL);
else
err = virtqueue_add_inbuf(vq, sg, num_sg,
dbuf, GFP_KERNEL);
if (err == -ENOSPC) {
if (!virtqueue_enable_cb_delayed(vq))
continue;
/* Swallow all notifies at once. */
if (read(to_guest[0], buf, sizeof(buf)) < 1)
break;
receives++;
virtqueue_disable_cb(vq);
continue;
}
if (err)
errx(1, "virtqueue_add_in/outbuf: %i", err);
xfers++;
virtqueue_kick(vq);
}
/* Any extra? */
while (finished != xfers) {
int *dbuf;
unsigned int len;
/* Consume bufs. */
dbuf = virtqueue_get_buf(vq, &len);
if (dbuf) {
if (len == 4)
assert(*dbuf == finished - 1);
else
assert(len == 0);
finished++;
continue;
}
if (!virtqueue_enable_cb_delayed(vq))
continue;
if (read(to_guest[0], buf, sizeof(buf)) < 1)
break;
receives++;
virtqueue_disable_cb(vq);
}
printf("Guest: notified %lu, pinged %lu\n",
gvdev.notifies, receives);
vring_del_virtqueue(vq);
return 0;
}
}
int main(int argc, char *argv[])
{
struct virtio_device vdev;
struct virtqueue *vq;
struct vringh vrh;
struct scatterlist guest_sg[RINGSIZE], *sgs[2];
struct iovec host_riov[2], host_wiov[2];
struct vringh_iov riov, wiov;
struct vring_used_elem used[RINGSIZE];
char buf[28];
u16 head;
int err;
unsigned i;
void *ret;
bool (*getrange)(struct vringh *vrh, u64 addr, struct vringh_range *r);
bool fast_vringh = false, parallel = false;
getrange = getrange_iov;
vdev.features[0] = 0;
while (argv[1]) {
if (strcmp(argv[1], "--indirect") == 0)
vdev.features[0] |= (1 << VIRTIO_RING_F_INDIRECT_DESC);
else if (strcmp(argv[1], "--eventidx") == 0)
vdev.features[0] |= (1 << VIRTIO_RING_F_EVENT_IDX);
else if (strcmp(argv[1], "--slow-range") == 0)
getrange = getrange_slow;
else if (strcmp(argv[1], "--fast-vringh") == 0)
fast_vringh = true;
else if (strcmp(argv[1], "--parallel") == 0)
parallel = true;
else
errx(1, "Unknown arg %s", argv[1]);
argv++;
}
if (parallel)
return parallel_test(vdev.features[0], getrange, fast_vringh);
if (posix_memalign(&__user_addr_min, PAGE_SIZE, USER_MEM) != 0)
abort();
__user_addr_max = __user_addr_min + USER_MEM;
memset(__user_addr_min, 0, vring_size(RINGSIZE, ALIGN));
/* Set up guest side. */
vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true,
__user_addr_min,
never_notify_host, never_callback_guest,
"guest vq");
/* Set up host side. */
vring_init(&vrh.vring, RINGSIZE, __user_addr_min, ALIGN);
vringh_init_user(&vrh, vdev.features[0], RINGSIZE, true,
vrh.vring.desc, vrh.vring.avail, vrh.vring.used);
/* No descriptor to get yet... */
err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
if (err != 0)
errx(1, "vringh_getdesc_user: %i", err);
/* Guest puts in a descriptor. */
memcpy(__user_addr_max - 1, "a", 1);
sg_init_table(guest_sg, 1);
sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1);
sg_init_table(guest_sg+1, 1);
sg_set_buf(&guest_sg[1], __user_addr_max - 3, 2);
sgs[0] = &guest_sg[0];
sgs[1] = &guest_sg[1];
/* May allocate an indirect, so force it to allocate user addr */
__kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN);
err = virtqueue_add_sgs(vq, sgs, 1, 1, &err, GFP_KERNEL);
if (err)
errx(1, "virtqueue_add_sgs: %i", err);
__kmalloc_fake = NULL;
/* Host retreives it. */
vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));
vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));
err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
if (err != 1)
errx(1, "vringh_getdesc_user: %i", err);
assert(riov.used == 1);
assert(riov.iov[0].iov_base == __user_addr_max - 1);
assert(riov.iov[0].iov_len == 1);
if (getrange != getrange_slow) {
assert(wiov.used == 1);
assert(wiov.iov[0].iov_base == __user_addr_max - 3);
assert(wiov.iov[0].iov_len == 2);
} else {
assert(wiov.used == 2);
assert(wiov.iov[0].iov_base == __user_addr_max - 3);
assert(wiov.iov[0].iov_len == 1);
assert(wiov.iov[1].iov_base == __user_addr_max - 2);
assert(wiov.iov[1].iov_len == 1);
}
err = vringh_iov_pull_user(&riov, buf, 5);
if (err != 1)
errx(1, "vringh_iov_pull_user: %i", err);
assert(buf[0] == 'a');
assert(riov.i == 1);
assert(vringh_iov_pull_user(&riov, buf, 5) == 0);
memcpy(buf, "bcdef", 5);
err = vringh_iov_push_user(&wiov, buf, 5);
if (err != 2)
errx(1, "vringh_iov_push_user: %i", err);
assert(memcmp(__user_addr_max - 3, "bc", 2) == 0);
assert(wiov.i == wiov.used);
assert(vringh_iov_push_user(&wiov, buf, 5) == 0);
/* Host is done. */
err = vringh_complete_user(&vrh, head, err);
if (err != 0)
errx(1, "vringh_complete_user: %i", err);
/* Guest should see used token now. */
__kfree_ignore_start = __user_addr_min + vring_size(RINGSIZE, ALIGN);
__kfree_ignore_end = __kfree_ignore_start + 1;
ret = virtqueue_get_buf(vq, &i);
if (ret != &err)
errx(1, "virtqueue_get_buf: %p", ret);
assert(i == 2);
/* Guest puts in a huge descriptor. */
sg_init_table(guest_sg, RINGSIZE);
for (i = 0; i < RINGSIZE; i++) {
sg_set_buf(&guest_sg[i],
__user_addr_max - USER_MEM/4, USER_MEM/4);
}
/* Fill contents with recognisable garbage. */
for (i = 0; i < USER_MEM/4; i++)
((char *)__user_addr_max - USER_MEM/4)[i] = i;
/* This will allocate an indirect, so force it to allocate user addr */
__kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN);
err = virtqueue_add_outbuf(vq, guest_sg, RINGSIZE, &err, GFP_KERNEL);
if (err)
errx(1, "virtqueue_add_outbuf (large): %i", err);
__kmalloc_fake = NULL;
/* Host picks it up (allocates new iov). */
vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));
vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));
err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
if (err != 1)
errx(1, "vringh_getdesc_user: %i", err);
assert(riov.max_num & VRINGH_IOV_ALLOCATED);
assert(riov.iov != host_riov);
if (getrange != getrange_slow)
assert(riov.used == RINGSIZE);
else
assert(riov.used == RINGSIZE * USER_MEM/4);
assert(!(wiov.max_num & VRINGH_IOV_ALLOCATED));
assert(wiov.used == 0);
/* Pull data back out (in odd chunks), should be as expected. */
for (i = 0; i < RINGSIZE * USER_MEM/4; i += 3) {
err = vringh_iov_pull_user(&riov, buf, 3);
if (err != 3 && i + err != RINGSIZE * USER_MEM/4)
errx(1, "vringh_iov_pull_user large: %i", err);
assert(buf[0] == (char)i);
assert(err < 2 || buf[1] == (char)(i + 1));
assert(err < 3 || buf[2] == (char)(i + 2));
}
assert(riov.i == riov.used);
vringh_iov_cleanup(&riov);
vringh_iov_cleanup(&wiov);
/* Complete using multi interface, just because we can. */
used[0].id = head;
used[0].len = 0;
err = vringh_complete_multi_user(&vrh, used, 1);
if (err)
errx(1, "vringh_complete_multi_user(1): %i", err);
/* Free up those descriptors. */
ret = virtqueue_get_buf(vq, &i);
if (ret != &err)
errx(1, "virtqueue_get_buf: %p", ret);
/* Add lots of descriptors. */
sg_init_table(guest_sg, 1);
sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1);
for (i = 0; i < RINGSIZE; i++) {
err = virtqueue_add_outbuf(vq, guest_sg, 1, &err, GFP_KERNEL);
if (err)
errx(1, "virtqueue_add_outbuf (multiple): %i", err);
}
/* Now get many, and consume them all at once. */
vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));
vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));
for (i = 0; i < RINGSIZE; i++) {
err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
if (err != 1)
errx(1, "vringh_getdesc_user: %i", err);
used[i].id = head;
used[i].len = 0;
}
/* Make sure it wraps around ring, to test! */
assert(vrh.vring.used->idx % RINGSIZE != 0);
err = vringh_complete_multi_user(&vrh, used, RINGSIZE);
if (err)
errx(1, "vringh_complete_multi_user: %i", err);
/* Free those buffers. */
for (i = 0; i < RINGSIZE; i++) {
unsigned len;
assert(virtqueue_get_buf(vq, &len) != NULL);
}
/* Test weird (but legal!) indirect. */
if (vdev.features[0] & (1 << VIRTIO_RING_F_INDIRECT_DESC)) {
char *data = __user_addr_max - USER_MEM/4;
struct vring_desc *d = __user_addr_max - USER_MEM/2;
struct vring vring;
/* Force creation of direct, which we modify. */
vdev.features[0] &= ~(1 << VIRTIO_RING_F_INDIRECT_DESC);
vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true,
__user_addr_min,
never_notify_host,
never_callback_guest,
"guest vq");
sg_init_table(guest_sg, 4);
sg_set_buf(&guest_sg[0], d, sizeof(*d)*2);
sg_set_buf(&guest_sg[1], d + 2, sizeof(*d)*1);
sg_set_buf(&guest_sg[2], data + 6, 4);
sg_set_buf(&guest_sg[3], d + 3, sizeof(*d)*3);
err = virtqueue_add_outbuf(vq, guest_sg, 4, &err, GFP_KERNEL);
if (err)
errx(1, "virtqueue_add_outbuf (indirect): %i", err);
vring_init(&vring, RINGSIZE, __user_addr_min, ALIGN);
/* They're used in order, but double-check... */
assert(vring.desc[0].addr == (unsigned long)d);
assert(vring.desc[1].addr == (unsigned long)(d+2));
assert(vring.desc[2].addr == (unsigned long)data + 6);
assert(vring.desc[3].addr == (unsigned long)(d+3));
vring.desc[0].flags |= VRING_DESC_F_INDIRECT;
vring.desc[1].flags |= VRING_DESC_F_INDIRECT;
vring.desc[3].flags |= VRING_DESC_F_INDIRECT;
/* First indirect */
d[0].addr = (unsigned long)data;
d[0].len = 1;
d[0].flags = VRING_DESC_F_NEXT;
d[0].next = 1;
d[1].addr = (unsigned long)data + 1;
d[1].len = 2;
d[1].flags = 0;
/* Second indirect */
d[2].addr = (unsigned long)data + 3;
d[2].len = 3;
d[2].flags = 0;
/* Third indirect */
d[3].addr = (unsigned long)data + 10;
d[3].len = 5;
d[3].flags = VRING_DESC_F_NEXT;
d[3].next = 1;
d[4].addr = (unsigned long)data + 15;
d[4].len = 6;
d[4].flags = VRING_DESC_F_NEXT;
d[4].next = 2;
d[5].addr = (unsigned long)data + 21;
d[5].len = 7;
d[5].flags = 0;
/* Host picks it up (allocates new iov). */
vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));
vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));
err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
if (err != 1)
errx(1, "vringh_getdesc_user: %i", err);
if (head != 0)
errx(1, "vringh_getdesc_user: head %i not 0", head);
assert(riov.max_num & VRINGH_IOV_ALLOCATED);
if (getrange != getrange_slow)
assert(riov.used == 7);
else
assert(riov.used == 28);
err = vringh_iov_pull_user(&riov, buf, 29);
assert(err == 28);
/* Data should be linear. */
for (i = 0; i < err; i++)
assert(buf[i] == i);
vringh_iov_cleanup(&riov);
}
/* Don't leak memory... */
vring_del_virtqueue(vq);
free(__user_addr_min);
return 0;
}
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