Skip to content

L
linux
Commit a75f8710 authored by Jesse Barnes's avatar Jesse Barnes Committed by Tony Luck
Browse files
Options

[IA64] swiotlb.c: long line, whitespace, and other cleanup 

Clean up swiotlb.c a bit in preparation for some other changes that might be 
coming (e.g. moving it to the top level lib/ directory, adding support for 
more uses).  Mostly whitespace and long line fixes, along with a few printk 
fixes.
Signed-off-by: default avatarJesse Barnes <jbarnes@sgi.com>
Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
parent 27b9590e
Show whitespace changes
Inline Side-by-side
Showing with 161 additions and 131 deletions
arch/ia64/lib/swiotlb.c
View file @ a75f8710
......@@ -44,21 +44,23 @@
#define IO_TLB_SEGSIZE 128
/*
* log of the size of each IO TLB slab. The number of slabs is command line controllable.
* log of the size of each IO TLB slab. The number of slabs is command line
* controllable.
*/
#define IO_TLB_SHIFT 11
int swiotlb_force;
/*
* Used to do a quick range check in swiotlb_unmap_single and swiotlb_sync_single_*, to see
* if the memory was in fact allocated by this API.
* Used to do a quick range check in swiotlb_unmap_single and
* swiotlb_sync_single_*, to see if the memory was in fact allocated by this
* API.
*/
static char *io_tlb_start, *io_tlb_end;
/*
* The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and io_tlb_end.
* This is command line adjustable via setup_io_tlb_npages.
* The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and
* io_tlb_end. This is command line adjustable via setup_io_tlb_npages.
* Default to 64MB.
*/
static unsigned long io_tlb_nslabs = 32768;
......@@ -71,14 +73,15 @@ static unsigned long io_tlb_overflow = 32*1024;
void *io_tlb_overflow_buffer;
/*
* This is a free list describing the number of free entries available from each index
* This is a free list describing the number of free entries available from
* each index
*/
static unsigned int *io_tlb_list;
static unsigned int io_tlb_index;
/*
* We need to save away the original address corresponding to a mapped entry for the sync
* operations.
* We need to save away the original address corresponding to a mapped entry
* for the sync operations.
*/
static unsigned char **io_tlb_orig_addr;
......@@ -88,10 +91,11 @@ static unsigned char **io_tlb_orig_addr;
static spinlock_t io_tlb_lock = SPIN_LOCK_UNLOCKED;
static int __init
setup_io_tlb_npages (char *str)
setup_io_tlb_npages(char *str)
{
if (isdigit(*str)) {
io_tlb_nslabs = simple_strtoul(str, &str, 0) << (PAGE_SHIFT - IO_TLB_SHIFT);
io_tlb_nslabs = simple_strtoul(str, &str, 0) <<
(PAGE_SHIFT - IO_TLB_SHIFT);
/* avoid tail segment of size < IO_TLB_SEGSIZE */
io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
}
......@@ -105,18 +109,19 @@ __setup("swiotlb=", setup_io_tlb_npages);
/* make io_tlb_overflow tunable too? */
/*
* Statically reserve bounce buffer space and initialize bounce buffer data structures for
* the software IO TLB used to implement the PCI DMA API.
* Statically reserve bounce buffer space and initialize bounce buffer data
* structures for the software IO TLB used to implement the PCI DMA API.
*/
void
swiotlb_init (void)
swiotlb_init(void)
{
unsigned long i;
/*
* Get IO TLB memory from the low pages
*/
io_tlb_start = alloc_bootmem_low_pages(io_tlb_nslabs * (1 << IO_TLB_SHIFT));
io_tlb_start = alloc_bootmem_low_pages(io_tlb_nslabs *
(1 << IO_TLB_SHIFT));
if (!io_tlb_start)
panic("Cannot allocate SWIOTLB buffer");
io_tlb_end = io_tlb_start + io_tlb_nslabs * (1 << IO_TLB_SHIFT);
......@@ -140,9 +145,11 @@ swiotlb_init (void)
virt_to_phys(io_tlb_start), virt_to_phys(io_tlb_end));
}
static inline int address_needs_mapping(struct device *hwdev, dma_addr_t addr)
static inline int
address_needs_mapping(struct device *hwdev, dma_addr_t addr)
{
dma_addr_t mask = 0xffffffff;
/* If the device has a mask, use it, otherwise default to 32 bits */
if (hwdev && hwdev->dma_mask)
mask = *hwdev->dma_mask;
return (addr & ~mask) != 0;
......@@ -152,7 +159,7 @@ static inline int address_needs_mapping(struct device *hwdev, dma_addr_t addr)
* Allocates bounce buffer and returns its kernel virtual address.
*/
static void *
map_single (struct device *hwdev, char *buffer, size_t size, int dir)
map_single(struct device *hwdev, char *buffer, size_t size, int dir)
{
unsigned long flags;
char *dma_addr;
......@@ -160,11 +167,11 @@ map_single (struct device *hwdev, char *buffer, size_t size, int dir)
int i;
/*
* For mappings greater than a page size, we limit the stride (and hence alignment)
* to a page size.
* For mappings greater than a page, we limit the stride (and
* hence alignment) to a page size.
*/
nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
if (size > (1 << PAGE_SHIFT))
if (size > PAGE_SIZE)
stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
else
stride = 1;
......@@ -173,8 +180,8 @@ map_single (struct device *hwdev, char *buffer, size_t size, int dir)
BUG();
/*
* Find suitable number of IO TLB entries size that will fit this request and
* allocate a buffer from that IO TLB pool.
* Find suitable number of IO TLB entries size that will fit this
* request and allocate a buffer from that IO TLB pool.
*/
spin_lock_irqsave(&io_tlb_lock, flags);
{
......@@ -185,22 +192,23 @@ map_single (struct device *hwdev, char *buffer, size_t size, int dir)
do {
/*
* If we find a slot that indicates we have 'nslots' number of
* contiguous buffers, we allocate the buffers from that slot and
* mark the entries as '0' indicating unavailable.
* If we find a slot that indicates we have 'nslots'
* number of contiguous buffers, we allocate the
* buffers from that slot and mark the entries as '0'
* indicating unavailable.
*/
if (io_tlb_list[index] >= nslots) {
int count = 0;
for (i = index; i < (int) (index + nslots); i++)
io_tlb_list[i] = 0;
for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1)
&& io_tlb_list[i]; i--)
for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--)
io_tlb_list[i] = ++count;
dma_addr = io_tlb_start + (index << IO_TLB_SHIFT);
/*
* Update the indices to avoid searching in the next round.
* Update the indices to avoid searching in
* the next round.
*/
io_tlb_index = ((index + nslots) < io_tlb_nslabs
? (index + nslots) : 0);
......@@ -219,8 +227,9 @@ map_single (struct device *hwdev, char *buffer, size_t size, int dir)
spin_unlock_irqrestore(&io_tlb_lock, flags);
/*
* Save away the mapping from the original address to the DMA address. This is
* needed when we sync the memory. Then we sync the buffer if needed.
* Save away the mapping from the original address to the DMA address.
* This is needed when we sync the memory. Then we sync the buffer if
* needed.
*/
io_tlb_orig_addr[index] = buffer;
if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
......@@ -233,10 +242,10 @@ map_single (struct device *hwdev, char *buffer, size_t size, int dir)
* dma_addr is the kernel virtual address of the bounce buffer to unmap.
*/
static void
unmap_single (struct device *hwdev, char *dma_addr, size_t size, int dir)
unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
{
unsigned long flags;
int i, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
char *buffer = io_tlb_orig_addr[index];
......@@ -245,40 +254,39 @@ unmap_single (struct device *hwdev, char *dma_addr, size_t size, int dir)
*/
if (buffer && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
/*
* bounce... copy the data back into the original buffer * and delete the
* bounce buffer.
* bounce... copy the data back into the original buffer * and
* delete the bounce buffer.
*/
memcpy(buffer, dma_addr, size);
/*
* Return the buffer to the free list by setting the corresponding entries to
* indicate the number of contigous entries available. While returning the
* entries to the free list, we merge the entries with slots below and above the
* pool being returned.
* Return the buffer to the free list by setting the corresponding
* entries to indicate the number of contigous entries available.
* While returning the entries to the free list, we merge the entries
* with slots below and above the pool being returned.
*/
spin_lock_irqsave(&io_tlb_lock, flags);
{
int count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
io_tlb_list[index + nslots] : 0);
/*
* Step 1: return the slots to the free list, merging the slots with
* superceeding slots
* Step 1: return the slots to the free list, merging the
* slots with superceeding slots
*/
for (i = index + nslots - 1; i >= index; i--)
io_tlb_list[i] = ++count;
/*
* Step 2: merge the returned slots with the preceding slots, if
* available (non zero)
* Step 2: merge the returned slots with the preceding slots,
* if available (non zero)
*/
for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) &&
io_tlb_list[i]; i--)
for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--)
io_tlb_list[i] = ++count;
}
spin_unlock_irqrestore(&io_tlb_lock, flags);
}
static void
sync_single (struct device *hwdev, char *dma_addr, size_t size, int dir)
sync_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
{
int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
char *buffer = io_tlb_orig_addr[index];
......@@ -296,13 +304,18 @@ sync_single (struct device *hwdev, char *dma_addr, size_t size, int dir)
}
void *
swiotlb_alloc_coherent (struct device *hwdev, size_t size, dma_addr_t *dma_handle, int flags)
swiotlb_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, int flags)
{
unsigned long dev_addr;
void *ret;
int order = get_order(size);
/* XXX fix me: the DMA API should pass us an explicit DMA mask instead: */
/*
* XXX fix me: the DMA API should pass us an explicit DMA mask
* instead, or use ZONE_DMA32 (ia64 overloads ZONE_DMA to be a ~32
* bit range instead of a 16MB one).
*/
flags |= GFP_DMA;
ret = (void *)__get_free_pages(flags, order);
......@@ -331,14 +344,21 @@ swiotlb_alloc_coherent (struct device *hwdev, size_t size, dma_addr_t *dma_handl
memset(ret, 0, size);
dev_addr = virt_to_phys(ret);
if (address_needs_mapping(hwdev,dev_addr))
panic("swiotlb_alloc_consistent: allocated memory is out of range for device");
/* Confirm address can be DMA'd by device */
if (address_needs_mapping(hwdev, dev_addr)) {
printk("hwdev DMA mask = 0x%016lx, dev_addr = 0x%016lx\n",
*hwdev->dma_mask, dev_addr);
panic("swiotlb_alloc_coherent: allocated memory is out of "
"range for device");
}
*dma_handle = dev_addr;
return ret;
}
void
swiotlb_free_coherent (struct device *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle)
swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
dma_addr_t dma_handle)
{
if (!(vaddr >= (void *)io_tlb_start
&& vaddr < (void *)io_tlb_end))
......@@ -348,7 +368,8 @@ swiotlb_free_coherent (struct device *hwdev, size_t size, void *vaddr, dma_addr_
swiotlb_unmap_single (hwdev, dma_handle, size, DMA_TO_DEVICE);
}
static void swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
static void
swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
{
/*
* Ran out of IOMMU space for this operation. This is very bad.
......@@ -357,10 +378,8 @@ static void swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
* When the mapping is small enough return a static buffer to limit
* the damage, or panic when the transfer is too big.
*/
printk(KERN_ERR
"PCI-DMA: Out of SW-IOMMU space for %lu bytes at device %s\n",
size, dev ? dev->bus_id : "?");
printk(KERN_ERR "PCI-DMA: Out of SW-IOMMU space for %lu bytes at "
"device %s\n", size, dev ? dev->bus_id : "?");
if (size > io_tlb_overflow && do_panic) {
if (dir == PCI_DMA_FROMDEVICE || dir == PCI_DMA_BIDIRECTIONAL)
......@@ -371,14 +390,14 @@ static void swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
}
/*
* Map a single buffer of the indicated size for DMA in streaming mode. The PCI address
* to use is returned.
* Map a single buffer of the indicated size for DMA in streaming mode. The
* PCI address to use is returned.
*
* Once the device is given the dma address, the device owns this memory until either
* swiotlb_unmap_single or swiotlb_dma_sync_single is performed.
* Once the device is given the dma address, the device owns this memory until
* either swiotlb_unmap_single or swiotlb_dma_sync_single is performed.
*/
dma_addr_t
swiotlb_map_single (struct device *hwdev, void *ptr, size_t size, int dir)
swiotlb_map_single(struct device *hwdev, void *ptr, size_t size, int dir)
{
unsigned long dev_addr = virt_to_phys(ptr);
void *map;
......@@ -386,17 +405,15 @@ swiotlb_map_single (struct device *hwdev, void *ptr, size_t size, int dir)
if (dir == DMA_NONE)
BUG();
/*
* Check if the PCI device can DMA to ptr... if so, just return ptr
* If the pointer passed in happens to be in the device's DMA window,
* we can safely return the device addr and not worry about bounce
* buffering it.
*/
if (!address_needs_mapping(hwdev, dev_addr) && !swiotlb_force)
/*
* Device is bit capable of DMA'ing to the buffer... just return the PCI
* address of ptr
*/
return dev_addr;
/*
* get a bounce buffer:
* Oh well, have to allocate and map a bounce buffer.
*/
map = map_single(hwdev, ptr, size, dir);
if (!map) {
......@@ -407,7 +424,7 @@ swiotlb_map_single (struct device *hwdev, void *ptr, size_t size, int dir)
dev_addr = virt_to_phys(map);
/*
* Ensure that the address returned is DMA'ble:
* Ensure that the address returned is DMA'ble
*/
if (address_needs_mapping(hwdev, dev_addr))
panic("map_single: bounce buffer is not DMA'ble");
......@@ -421,7 +438,7 @@ swiotlb_map_single (struct device *hwdev, void *ptr, size_t size, int dir)
* flush them when they get mapped into an executable vm-area.
*/
static void
mark_clean (void *addr, size_t size)
mark_clean(void *addr, size_t size)
{
unsigned long pg_addr, end;
......@@ -435,15 +452,16 @@ mark_clean (void *addr, size_t size)
}
/*
* Unmap a single streaming mode DMA translation. The dma_addr and size must match what
* was provided for in a previous swiotlb_map_single call. All other usages are
* undefined.
* Unmap a single streaming mode DMA translation. The dma_addr and size must
* match what was provided for in a previous swiotlb_map_single call. All
* other usages are undefined.
*
* After this call, reads by the cpu to the buffer are guaranteed to see whatever the
* device wrote there.
* After this call, reads by the cpu to the buffer are guaranteed to see
* whatever the device wrote there.
*/
void
swiotlb_unmap_single (struct device *hwdev, dma_addr_t dev_addr, size_t size, int dir)
swiotlb_unmap_single(struct device *hwdev, dma_addr_t dev_addr, size_t size,
int dir)
{
char *dma_addr = phys_to_virt(dev_addr);
......@@ -456,16 +474,18 @@ swiotlb_unmap_single (struct device *hwdev, dma_addr_t dev_addr, size_t size, in
}
/*
* Make physical memory consistent for a single streaming mode DMA translation after a
* transfer.
* Make physical memory consistent for a single streaming mode DMA translation
* after a transfer.
*
* If you perform a swiotlb_map_single() but wish to interrogate the buffer using the cpu,
* yet do not wish to teardown the PCI dma mapping, you must call this function before
* doing so. At the next point you give the PCI dma address back to the card, you must
* first perform a swiotlb_dma_sync_for_device, and then the device again owns the buffer
* If you perform a swiotlb_map_single() but wish to interrogate the buffer
* using the cpu, yet do not wish to teardown the PCI dma mapping, you must
* call this function before doing so. At the next point you give the PCI dma
* address back to the card, you must first perform a
* swiotlb_dma_sync_for_device, and then the device again owns the buffer
*/
void
swiotlb_sync_single_for_cpu (struct device *hwdev, dma_addr_t dev_addr, size_t size, int dir)
swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
size_t size, int dir)
{
char *dma_addr = phys_to_virt(dev_addr);
......@@ -478,7 +498,8 @@ swiotlb_sync_single_for_cpu (struct device *hwdev, dma_addr_t dev_addr, size_t s
}
void
swiotlb_sync_single_for_device (struct device *hwdev, dma_addr_t dev_addr, size_t size, int dir)
swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
size_t size, int dir)
{
char *dma_addr = phys_to_virt(dev_addr);
......@@ -491,10 +512,11 @@ swiotlb_sync_single_for_device (struct device *hwdev, dma_addr_t dev_addr, size_
}
/*
* Map a set of buffers described by scatterlist in streaming mode for DMA. This is the
* scatter-gather version of the above swiotlb_map_single interface. Here the scatter
* gather list elements are each tagged with the appropriate dma address and length. They
* are obtained via sg_dma_{address,length}(SG).
* Map a set of buffers described by scatterlist in streaming mode for DMA.
* This is the scatter-gather version of the above swiotlb_map_single
* interface. Here the scatter gather list elements are each tagged with the
* appropriate dma address and length. They are obtained via
* sg_dma_{address,length}(SG).
*
* NOTE: An implementation may be able to use a smaller number of
* DMA address/length pairs than there are SG table elements.
......@@ -502,10 +524,12 @@ swiotlb_sync_single_for_device (struct device *hwdev, dma_addr_t dev_addr, size_
* The routine returns the number of addr/length pairs actually
* used, at most nents.
*
* Device ownership issues as mentioned above for swiotlb_map_single are the same here.
* Device ownership issues as mentioned above for swiotlb_map_single are the
* same here.
*/
int
swiotlb_map_sg (struct device *hwdev, struct scatterlist *sg, int nelems, int dir)
swiotlb_map_sg(struct device *hwdev, struct scatterlist *sg, int nelems,
int dir)
{
void *addr;
unsigned long dev_addr;
......@@ -520,7 +544,7 @@ swiotlb_map_sg (struct device *hwdev, struct scatterlist *sg, int nelems, int di
if (swiotlb_force || address_needs_mapping(hwdev, dev_addr)) {
sg->dma_address = (dma_addr_t) virt_to_phys(map_single(hwdev, addr, sg->length, dir));
if (!sg->dma_address) {
/* Don't panic here, we expect pci_map_sg users
/* Don't panic here, we expect map_sg users
to do proper error handling. */
swiotlb_full(hwdev, sg->length, dir, 0);
swiotlb_unmap_sg(hwdev, sg - i, i, dir);
......@@ -535,11 +559,12 @@ swiotlb_map_sg (struct device *hwdev, struct scatterlist *sg, int nelems, int di
}
/*
* Unmap a set of streaming mode DMA translations. Again, cpu read rules concerning calls
* here are the same as for swiotlb_unmap_single() above.
* Unmap a set of streaming mode DMA translations. Again, cpu read rules
* concerning calls here are the same as for swiotlb_unmap_single() above.
*/
void
swiotlb_unmap_sg (struct device *hwdev, struct scatterlist *sg, int nelems, int dir)
swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sg, int nelems,
int dir)
{
int i;
......@@ -554,14 +579,15 @@ swiotlb_unmap_sg (struct device *hwdev, struct scatterlist *sg, int nelems, int
}
/*
* Make physical memory consistent for a set of streaming mode DMA translations after a
* transfer.
* Make physical memory consistent for a set of streaming mode DMA translations
* after a transfer.
*
* The same as swiotlb_sync_single_* but for a scatter-gather list, same rules and
* usage.
* The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
* and usage.
*/
void
swiotlb_sync_sg_for_cpu (struct device *hwdev, struct scatterlist *sg, int nelems, int dir)
swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
int nelems, int dir)
{
int i;
......@@ -570,11 +596,13 @@ swiotlb_sync_sg_for_cpu (struct device *hwdev, struct scatterlist *sg, int nelem
for (i = 0; i < nelems; i++, sg++)
if (sg->dma_address != SG_ENT_PHYS_ADDRESS(sg))
sync_single(hwdev, (void *) sg->dma_address, sg->dma_length, dir);
sync_single(hwdev, (void *) sg->dma_address,
sg->dma_length, dir);
}
void
swiotlb_sync_sg_for_device (struct device *hwdev, struct scatterlist *sg, int nelems, int dir)
swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
int nelems, int dir)
{
int i;
......@@ -583,19 +611,21 @@ swiotlb_sync_sg_for_device (struct device *hwdev, struct scatterlist *sg, int ne
for (i = 0; i < nelems; i++, sg++)
if (sg->dma_address != SG_ENT_PHYS_ADDRESS(sg))
sync_single(hwdev, (void *) sg->dma_address, sg->dma_length, dir);
sync_single(hwdev, (void *) sg->dma_address,
sg->dma_length, dir);
}
int
swiotlb_dma_mapping_error (dma_addr_t dma_addr)
swiotlb_dma_mapping_error(dma_addr_t dma_addr)
{
return (dma_addr == virt_to_phys(io_tlb_overflow_buffer));
}
/*
* Return whether the given PCI device DMA address mask can be supported properly. For
* example, if your device can only drive the low 24-bits during PCI bus mastering, then
* you would pass 0x00ffffff as the mask to this function.
* Return whether the given PCI device DMA address mask can be supported
* properly. For example, if your device can only drive the low 24-bits
* during PCI bus mastering, then you would pass 0x00ffffff as the mask to
* this function.
*/
int
swiotlb_dma_supported (struct device *hwdev, u64 mask)
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7