Merge tag 'for-linus-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:
 "This contains some minor code cleanups (fixing return types of
  functions), some fixes for Linux running as Xen PVH guest, and adding
  of a new guest resource mapping feature for Xen tools"

* tag 'for-linus-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/PVH: Make GDT selectors PVH-specific
  xen/PVH: Set up GS segment for stack canary
  xen/store: do not store local values in xen_start_info
  xen-netfront: fix xennet_start_xmit()'s return type
  xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE
  xen: Change return type to vm_fault_t

arch/arm/xen/enlighten.c

@@ -89,6 +89,17 @@ int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
 }
 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);
 
+/* Not used by XENFEAT_auto_translated guests. */
+int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
+			       unsigned long addr,
+			       xen_pfn_t *mfn, int nr,
+			       int *err_ptr, pgprot_t prot,
+			       unsigned int domid, struct page **pages)
+{
+	return -ENOSYS;
+}
+EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
+
 static void xen_read_wallclock(struct timespec64 *ts)
 {
 	u32 version;

arch/x86/xen/mmu.c

@@ -63,37 +63,44 @@ static noinline void xen_flush_tlb_all(void)
 #define REMAP_BATCH_SIZE 16
 
 struct remap_data {
-	xen_pfn_t *mfn;
+	xen_pfn_t *pfn;
 	bool contiguous;
+	bool no_translate;
 	pgprot_t prot;
 	struct mmu_update *mmu_update;
 };
 
-static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token,
+static int remap_area_pfn_pte_fn(pte_t *ptep, pgtable_t token,
 				 unsigned long addr, void *data)
 {
 	struct remap_data *rmd = data;
-	pte_t pte = pte_mkspecial(mfn_pte(*rmd->mfn, rmd->prot));
+	pte_t pte = pte_mkspecial(mfn_pte(*rmd->pfn, rmd->prot));
 
-	/* If we have a contiguous range, just update the mfn itself,
-	   else update pointer to be "next mfn". */
+	/*
+	 * If we have a contiguous range, just update the pfn itself,
+	 * else update pointer to be "next pfn".
+	 */
 	if (rmd->contiguous)
-		(*rmd->mfn)++;
+		(*rmd->pfn)++;
 	else
-		rmd->mfn++;
+		rmd->pfn++;
 
-	rmd->mmu_update->ptr = virt_to_machine(ptep).maddr | MMU_NORMAL_PT_UPDATE;
+	rmd->mmu_update->ptr = virt_to_machine(ptep).maddr;
+	rmd->mmu_update->ptr |= rmd->no_translate ?
+		MMU_PT_UPDATE_NO_TRANSLATE :
+		MMU_NORMAL_PT_UPDATE;
 	rmd->mmu_update->val = pte_val_ma(pte);
 	rmd->mmu_update++;
 
 	return 0;
 }
 
-static int do_remap_gfn(struct vm_area_struct *vma,
+static int do_remap_pfn(struct vm_area_struct *vma,
 			unsigned long addr,
-			xen_pfn_t *gfn, int nr,
+			xen_pfn_t *pfn, int nr,
 			int *err_ptr, pgprot_t prot,
-			unsigned domid,
+			unsigned int domid,
+			bool no_translate,
 			struct page **pages)
 {
 	int err = 0;
@@ -104,11 +111,14 @@ static int do_remap_gfn(struct vm_area_struct *vma,
 
 	BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO)));
 
-	rmd.mfn = gfn;
+	rmd.pfn = pfn;
 	rmd.prot = prot;
-	/* We use the err_ptr to indicate if there we are doing a contiguous
-	 * mapping or a discontigious mapping. */
+	/*
+	 * We use the err_ptr to indicate if there we are doing a contiguous
+	 * mapping or a discontigious mapping.
+	 */
 	rmd.contiguous = !err_ptr;
+	rmd.no_translate = no_translate;
 
 	while (nr) {
 		int index = 0;
@@ -119,7 +129,7 @@ static int do_remap_gfn(struct vm_area_struct *vma,
 
 		rmd.mmu_update = mmu_update;
 		err = apply_to_page_range(vma->vm_mm, addr, range,
-					  remap_area_mfn_pte_fn, &rmd);
+					  remap_area_pfn_pte_fn, &rmd);
 		if (err)
 			goto out;
 
@@ -173,7 +183,8 @@ int xen_remap_domain_gfn_range(struct vm_area_struct *vma,
 	if (xen_feature(XENFEAT_auto_translated_physmap))
 		return -EOPNOTSUPP;
 
-	return do_remap_gfn(vma, addr, &gfn, nr, NULL, prot, domid, pages);
+	return do_remap_pfn(vma, addr, &gfn, nr, NULL, prot, domid, false,
+			    pages);
 }
 EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range);
 
@@ -192,10 +203,25 @@ int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
 	 * cause of "wrong memory was mapped in".
 	 */
 	BUG_ON(err_ptr == NULL);
-	return do_remap_gfn(vma, addr, gfn, nr, err_ptr, prot, domid, pages);
+	return do_remap_pfn(vma, addr, gfn, nr, err_ptr, prot, domid,
+			    false, pages);
 }
 EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array);
 
+int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
+			       unsigned long addr,
+			       xen_pfn_t *mfn, int nr,
+			       int *err_ptr, pgprot_t prot,
+			       unsigned int domid, struct page **pages)
+{
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		return -EOPNOTSUPP;
+
+	return do_remap_pfn(vma, addr, mfn, nr, err_ptr, prot, domid,
+			    true, pages);
+}
+EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
+
 /* Returns: 0 success */
 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
 			       int nr, struct page **pages)

arch/x86/xen/xen-pvh.S

@@ -54,12 +54,19 @@
  * charge of setting up it's own stack, GDT and IDT.
  */
 
+#define PVH_GDT_ENTRY_CS	1
+#define PVH_GDT_ENTRY_DS	2
+#define PVH_GDT_ENTRY_CANARY	3
+#define PVH_CS_SEL		(PVH_GDT_ENTRY_CS * 8)
+#define PVH_DS_SEL		(PVH_GDT_ENTRY_DS * 8)
+#define PVH_CANARY_SEL		(PVH_GDT_ENTRY_CANARY * 8)
+
 ENTRY(pvh_start_xen)
 	cld
 
 	lgdt (_pa(gdt))
 
-	mov $(__BOOT_DS),%eax
+	mov $PVH_DS_SEL,%eax
 	mov %eax,%ds
 	mov %eax,%es
 	mov %eax,%ss
@@ -93,11 +100,17 @@ ENTRY(pvh_start_xen)
 	mov %eax, %cr0
 
 	/* Jump to 64-bit mode. */
-	ljmp $__KERNEL_CS, $_pa(1f)
+	ljmp $PVH_CS_SEL, $_pa(1f)
 
 	/* 64-bit entry point. */
 	.code64
 1:
+	/* Set base address in stack canary descriptor. */
+	mov $MSR_GS_BASE,%ecx
+	mov $_pa(canary), %eax
+	xor %edx, %edx
+	wrmsr
+
 	call xen_prepare_pvh
 
 	/* startup_64 expects boot_params in %rsi. */
@@ -107,6 +120,17 @@ ENTRY(pvh_start_xen)
 
 #else /* CONFIG_X86_64 */
 
+	/* Set base address in stack canary descriptor. */
+	movl $_pa(gdt_start),%eax
+	movl $_pa(canary),%ecx
+	movw %cx, (PVH_GDT_ENTRY_CANARY * 8) + 2(%eax)
+	shrl $16, %ecx
+	movb %cl, (PVH_GDT_ENTRY_CANARY * 8) + 4(%eax)
+	movb %ch, (PVH_GDT_ENTRY_CANARY * 8) + 7(%eax)
+
+	mov $PVH_CANARY_SEL,%eax
+	mov %eax,%gs
+
 	call mk_early_pgtbl_32
 
 	mov $_pa(initial_page_table), %eax
@@ -116,13 +140,13 @@ ENTRY(pvh_start_xen)
 	or $(X86_CR0_PG | X86_CR0_PE), %eax
 	mov %eax, %cr0
 
-	ljmp $__BOOT_CS, $1f
+	ljmp $PVH_CS_SEL, $1f
 1:
 	call xen_prepare_pvh
 	mov $_pa(pvh_bootparams), %esi
 
 	/* startup_32 doesn't expect paging and PAE to be on. */
-	ljmp $__BOOT_CS, $_pa(2f)
+	ljmp $PVH_CS_SEL, $_pa(2f)
 2:
 	mov %cr0, %eax
 	and $~X86_CR0_PG, %eax
@@ -131,7 +155,7 @@ ENTRY(pvh_start_xen)
 	and $~X86_CR4_PAE, %eax
 	mov %eax, %cr4
 
-	ljmp $__BOOT_CS, $_pa(startup_32)
+	ljmp $PVH_CS_SEL, $_pa(startup_32)
 #endif
 END(pvh_start_xen)
 
@@ -143,16 +167,19 @@ gdt:
 	.word 0
 gdt_start:
 	.quad 0x0000000000000000            /* NULL descriptor */
-	.quad 0x0000000000000000            /* reserved */
 #ifdef CONFIG_X86_64
-	.quad GDT_ENTRY(0xa09a, 0, 0xfffff) /* __KERNEL_CS */
+	.quad GDT_ENTRY(0xa09a, 0, 0xfffff) /* PVH_CS_SEL */
 #else
-	.quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* __KERNEL_CS */
+	.quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* PVH_CS_SEL */
 #endif
-	.quad GDT_ENTRY(0xc092, 0, 0xfffff) /* __KERNEL_DS */
+	.quad GDT_ENTRY(0xc092, 0, 0xfffff) /* PVH_DS_SEL */
+	.quad GDT_ENTRY(0x4090, 0, 0x18)    /* PVH_CANARY_SEL */
 gdt_end:
 
-	.balign 4
+	.balign 16
+canary:
+	.fill 48, 1, 0
+
 early_stack:
 	.fill 256, 1, 0
 early_stack_end:

drivers/net/xen-netfront.c

@@ -564,7 +564,7 @@ static u16 xennet_select_queue(struct net_device *dev, struct sk_buff *skb,
 
 #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1)
 
-static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t xennet_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct netfront_info *np = netdev_priv(dev);
 	struct netfront_stats *tx_stats = this_cpu_ptr(np->tx_stats);

drivers/xen/privcmd.c

@@ -33,6 +33,7 @@
 #include <xen/xen.h>
 #include <xen/privcmd.h>
 #include <xen/interface/xen.h>
+#include <xen/interface/memory.h>
 #include <xen/interface/hvm/dm_op.h>
 #include <xen/features.h>
 #include <xen/page.h>
@@ -722,6 +723,134 @@ static long privcmd_ioctl_restrict(struct file *file, void __user *udata)
 	return 0;
 }
 
+struct remap_pfn {
+	struct mm_struct *mm;
+	struct page **pages;
+	pgprot_t prot;
+	unsigned long i;
+};
+
+static int remap_pfn_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
+			void *data)
+{
+	struct remap_pfn *r = data;
+	struct page *page = r->pages[r->i];
+	pte_t pte = pte_mkspecial(pfn_pte(page_to_pfn(page), r->prot));
+
+	set_pte_at(r->mm, addr, ptep, pte);
+	r->i++;
+
+	return 0;
+}
+
+static long privcmd_ioctl_mmap_resource(struct file *file, void __user *udata)
+{
+	struct privcmd_data *data = file->private_data;
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	struct privcmd_mmap_resource kdata;
+	xen_pfn_t *pfns = NULL;
+	struct xen_mem_acquire_resource xdata;
+	int rc;
+
+	if (copy_from_user(&kdata, udata, sizeof(kdata)))
+		return -EFAULT;
+
+	/* If restriction is in place, check the domid matches */
+	if (data->domid != DOMID_INVALID && data->domid != kdata.dom)
+		return -EPERM;
+
+	down_write(&mm->mmap_sem);
+
+	vma = find_vma(mm, kdata.addr);
+	if (!vma || vma->vm_ops != &privcmd_vm_ops) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	pfns = kcalloc(kdata.num, sizeof(*pfns), GFP_KERNEL);
+	if (!pfns) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	if (xen_feature(XENFEAT_auto_translated_physmap)) {
+		unsigned int nr = DIV_ROUND_UP(kdata.num, XEN_PFN_PER_PAGE);
+		struct page **pages;
+		unsigned int i;
+
+		rc = alloc_empty_pages(vma, nr);
+		if (rc < 0)
+			goto out;
+
+		pages = vma->vm_private_data;
+		for (i = 0; i < kdata.num; i++) {
+			xen_pfn_t pfn =
+				page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]);
+
+			pfns[i] = pfn + (i % XEN_PFN_PER_PAGE);
+		}
+	} else
+		vma->vm_private_data = PRIV_VMA_LOCKED;
+
+	memset(&xdata, 0, sizeof(xdata));
+	xdata.domid = kdata.dom;
+	xdata.type = kdata.type;
+	xdata.id = kdata.id;
+	xdata.frame = kdata.idx;
+	xdata.nr_frames = kdata.num;
+	set_xen_guest_handle(xdata.frame_list, pfns);
+
+	xen_preemptible_hcall_begin();
+	rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata);
+	xen_preemptible_hcall_end();
+
+	if (rc)
+		goto out;
+
+	if (xen_feature(XENFEAT_auto_translated_physmap)) {
+		struct remap_pfn r = {
+			.mm = vma->vm_mm,
+			.pages = vma->vm_private_data,
+			.prot = vma->vm_page_prot,
+		};
+
+		rc = apply_to_page_range(r.mm, kdata.addr,
+					 kdata.num << PAGE_SHIFT,
+					 remap_pfn_fn, &r);
+	} else {
+		unsigned int domid =
+			(xdata.flags & XENMEM_rsrc_acq_caller_owned) ?
+			DOMID_SELF : kdata.dom;
+		int num;
+
+		num = xen_remap_domain_mfn_array(vma,
+						 kdata.addr & PAGE_MASK,
+						 pfns, kdata.num, (int *)pfns,
+						 vma->vm_page_prot,
+						 domid,
+						 vma->vm_private_data);
+		if (num < 0)
+			rc = num;
+		else if (num != kdata.num) {
+			unsigned int i;
+
+			for (i = 0; i < num; i++) {
+				rc = pfns[i];
+				if (rc < 0)
+					break;
+			}
+		} else
+			rc = 0;
+	}
+
+out:
+	up_write(&mm->mmap_sem);
+	kfree(pfns);
+
+	return rc;
+}
+
 static long privcmd_ioctl(struct file *file,
 			  unsigned int cmd, unsigned long data)
 {
@@ -753,6 +882,10 @@ static long privcmd_ioctl(struct file *file,
 		ret = privcmd_ioctl_restrict(file, udata);
 		break;
 
+	case IOCTL_PRIVCMD_MMAP_RESOURCE:
+		ret = privcmd_ioctl_mmap_resource(file, udata);
+		break;
+
 	default:
 		break;
 	}
@@ -801,7 +934,7 @@ static void privcmd_close(struct vm_area_struct *vma)
 	kfree(pages);
 }
 
-static int privcmd_fault(struct vm_fault *vmf)
+static vm_fault_t privcmd_fault(struct vm_fault *vmf)
 {
 	printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n",
 	       vmf->vma, vmf->vma->vm_start, vmf->vma->vm_end,

drivers/xen/xenbus/xenbus_probe.c

@@ -710,7 +710,7 @@ static int __init xenstored_local_init(void)
 	if (!page)
 		goto out_err;
 
-	xen_store_gfn = xen_start_info->store_mfn = virt_to_gfn((void *)page);
+	xen_store_gfn = virt_to_gfn((void *)page);
 
 	/* Next allocate a local port which xenstored can bind to */
 	alloc_unbound.dom        = DOMID_SELF;
@@ -722,8 +722,7 @@ static int __init xenstored_local_init(void)
 		goto out_err;
 
 	BUG_ON(err);
-	xen_store_evtchn = xen_start_info->store_evtchn =
-		alloc_unbound.port;
+	xen_store_evtchn = alloc_unbound.port;
 
 	return 0;
 

include/uapi/xen/privcmd.h

@@ -89,6 +89,15 @@ struct privcmd_dm_op {
 	const struct privcmd_dm_op_buf __user *ubufs;
 };
 
+struct privcmd_mmap_resource {
+	domid_t dom;
+	__u32 type;
+	__u32 id;
+	__u32 idx;
+	__u64 num;
+	__u64 addr;
+};
+
 /*
  * @cmd: IOCTL_PRIVCMD_HYPERCALL
  * @arg: &privcmd_hypercall_t
@@ -114,5 +123,7 @@ struct privcmd_dm_op {
 	_IOC(_IOC_NONE, 'P', 5, sizeof(struct privcmd_dm_op))
 #define IOCTL_PRIVCMD_RESTRICT					\
 	_IOC(_IOC_NONE, 'P', 6, sizeof(domid_t))
+#define IOCTL_PRIVCMD_MMAP_RESOURCE				\
+	_IOC(_IOC_NONE, 'P', 7, sizeof(struct privcmd_mmap_resource))
 
 #endif /* __LINUX_PUBLIC_PRIVCMD_H__ */

include/xen/interface/memory.h

@@ -265,4 +265,70 @@ struct xen_remove_from_physmap {
 };
 DEFINE_GUEST_HANDLE_STRUCT(xen_remove_from_physmap);
 
+/*
+ * Get the pages for a particular guest resource, so that they can be
+ * mapped directly by a tools domain.
+ */
+#define XENMEM_acquire_resource 28
+struct xen_mem_acquire_resource {
+    /* IN - The domain whose resource is to be mapped */
+    domid_t domid;
+    /* IN - the type of resource */
+    uint16_t type;
+
+#define XENMEM_resource_ioreq_server 0
+#define XENMEM_resource_grant_table 1
+
+    /*
+     * IN - a type-specific resource identifier, which must be zero
+     *      unless stated otherwise.
+     *
+     * type == XENMEM_resource_ioreq_server -> id == ioreq server id
+     * type == XENMEM_resource_grant_table -> id defined below
+     */
+    uint32_t id;
+
+#define XENMEM_resource_grant_table_id_shared 0
+#define XENMEM_resource_grant_table_id_status 1
+
+    /* IN/OUT - As an IN parameter number of frames of the resource
+     *          to be mapped. However, if the specified value is 0 and
+     *          frame_list is NULL then this field will be set to the
+     *          maximum value supported by the implementation on return.
+     */
+    uint32_t nr_frames;
+    /*
+     * OUT - Must be zero on entry. On return this may contain a bitwise
+     *       OR of the following values.
+     */
+    uint32_t flags;
+
+    /* The resource pages have been assigned to the calling domain */
+#define _XENMEM_rsrc_acq_caller_owned 0
+#define XENMEM_rsrc_acq_caller_owned (1u << _XENMEM_rsrc_acq_caller_owned)
+
+    /*
+     * IN - the index of the initial frame to be mapped. This parameter
+     *      is ignored if nr_frames is 0.
+     */
+    uint64_t frame;
+
+#define XENMEM_resource_ioreq_server_frame_bufioreq 0
+#define XENMEM_resource_ioreq_server_frame_ioreq(n) (1 + (n))
+
+    /*
+     * IN/OUT - If the tools domain is PV then, upon return, frame_list
+     *          will be populated with the MFNs of the resource.
+     *          If the tools domain is HVM then it is expected that, on
+     *          entry, frame_list will be populated with a list of GFNs
+     *          that will be mapped to the MFNs of the resource.
+     *          If -EIO is returned then the frame_list has only been
+     *          partially mapped and it is up to the caller to unmap all
+     *          the GFNs.
+     *          This parameter may be NULL if nr_frames is 0.
+     */
+    GUEST_HANDLE(xen_pfn_t) frame_list;
+};
+DEFINE_GUEST_HANDLE_STRUCT(xen_mem_acquire_resource);
+
 #endif /* __XEN_PUBLIC_MEMORY_H__ */

include/xen/interface/xen.h

@@ -268,6 +268,7 @@
 #define MMU_NORMAL_PT_UPDATE       0 /* checked '*ptr = val'. ptr is MA.      */
 #define MMU_MACHPHYS_UPDATE        1 /* ptr = MA of frame to modify entry for */
 #define MMU_PT_UPDATE_PRESERVE_AD  2 /* atomically: *ptr = val | (*ptr&(A|D)) */
+#define MMU_PT_UPDATE_NO_TRANSLATE 3 /* checked '*ptr = val'. ptr is MA.      */
 
 /*
  * MMU EXTENDED OPERATIONS

include/xen/xen-ops.h

@@ -63,7 +63,7 @@ static inline void xen_destroy_contiguous_region(phys_addr_t pstart,
 struct vm_area_struct;
 
 /*
- * xen_remap_domain_gfn_array() - map an array of foreign frames
+ * xen_remap_domain_gfn_array() - map an array of foreign frames by gfn
  * @vma:     VMA to map the pages into
  * @addr:    Address at which to map the pages
  * @gfn:     Array of GFNs to map
@@ -86,6 +86,28 @@ int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
 			       unsigned domid,
 			       struct page **pages);
 
+/*
+ * xen_remap_domain_mfn_array() - map an array of foreign frames by mfn
+ * @vma:     VMA to map the pages into
+ * @addr:    Address at which to map the pages
+ * @mfn:     Array of MFNs to map
+ * @nr:      Number entries in the MFN array
+ * @err_ptr: Returns per-MFN error status.
+ * @prot:    page protection mask
+ * @domid:   Domain owning the pages
+ * @pages:   Array of pages if this domain has an auto-translated physmap
+ *
+ * @mfn and @err_ptr may point to the same buffer, the MFNs will be
+ * overwritten by the error codes after they are mapped.
+ *
+ * Returns the number of successfully mapped frames, or a -ve error
+ * code.
+ */
+int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
+			       unsigned long addr, xen_pfn_t *mfn, int nr,
+			       int *err_ptr, pgprot_t prot,
+			       unsigned int domid, struct page **pages);
+
 /* xen_remap_domain_gfn_range() - map a range of foreign frames
  * @vma:     VMA to map the pages into
  * @addr:    Address at which to map the pages