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

3 files changed, 91 insertions, 27 deletions

diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index ba7f4c8f5c3e..8073625371f5 100644
--- a/arch/arm/xen/enlighten.c
+++ b/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;
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 2d76106788a3..96fc2f0fdbfe 100644
--- a/arch/x86/xen/mmu.c
+++ b/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)
diff --git a/arch/x86/xen/xen-pvh.S b/arch/x86/xen/xen-pvh.S
index e1a5fbeae08d..ca2d3b2bf2af 100644
--- a/arch/x86/xen/xen-pvh.S
+++ b/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: