diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 74a702674e866fd7346a348234ac9d8e06d0f3c6..0eb572eda4060338543bd0dfc97cf05bccaeb6cb 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -677,7 +677,7 @@ int track_pfn_copy(struct vm_area_struct *vma)
unsigned long vma_size = vma->vm_end - vma->vm_start;
pgprot_t pgprot;
- if (is_linear_pfn_mapping(vma)) {
+ if (vma->vm_flags & VM_PAT) {
/*
* reserve the whole chunk covered by vma. We need the
* starting address and protection from pte.
@@ -699,14 +699,20 @@ int track_pfn_copy(struct vm_area_struct *vma)
* single reserve_pfn_range call.
*/
int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
- unsigned long pfn, unsigned long size)
+ unsigned long pfn, unsigned long addr, unsigned long size)
{
resource_size_t paddr = (resource_size_t)pfn << PAGE_SHIFT;
unsigned long flags;
/* reserve the whole chunk starting from paddr */
- if (is_linear_pfn_mapping(vma))
- return reserve_pfn_range(paddr, size, prot, 0);
+ if (addr == vma->vm_start && size == (vma->vm_end - vma->vm_start)) {
+ int ret;
+
+ ret = reserve_pfn_range(paddr, size, prot, 0);
+ if (!ret)
+ vma->vm_flags |= VM_PAT;
+ return ret;
+ }
if (!pat_enabled)
return 0;
@@ -758,7 +764,7 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
resource_size_t paddr;
unsigned long prot;
- if (!is_linear_pfn_mapping(vma))
+ if (!(vma->vm_flags & VM_PAT))
return;
/* free the chunk starting from pfn or the whole chunk */
@@ -772,6 +778,7 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
size = vma->vm_end - vma->vm_start;
}
free_pfn_range(paddr, size);
+ vma->vm_flags &= ~VM_PAT;
}
pgprot_t pgprot_writecombine(pgprot_t prot)
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index d4d4592c97fc8d7909617253568a961866a66158..c9a612069c8ebd2726ce0d819156c2ec7bc1297e 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -391,7 +391,8 @@ static inline void ptep_modify_prot_commit(struct mm_struct *mm,
* by remap_pfn_range() for physical range indicated by pfn and size.
*/
static inline int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
- unsigned long pfn, unsigned long size)
+ unsigned long pfn, unsigned long addr,
+ unsigned long size)
{
return 0;
}
@@ -426,7 +427,8 @@ static inline void untrack_pfn(struct vm_area_struct *vma,
}
#else
extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
- unsigned long pfn, unsigned long size);
+ unsigned long pfn, unsigned long addr,
+ unsigned long size);
extern int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
unsigned long pfn);
extern int track_pfn_copy(struct vm_area_struct *vma);
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 311be906b57d8498d5c3529d0e42de0996a0c1ec..75d1632d3477ee9ac792cb222f86aeff50f0ccf2 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -117,7 +117,7 @@ extern unsigned int kobjsize(const void *objp);
#define VM_CAN_NONLINEAR 0x08000000 /* Has ->fault & does nonlinear pages */
#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
#define VM_SAO 0x20000000 /* Strong Access Ordering (powerpc) */
-#define VM_PFN_AT_MMAP 0x40000000 /* PFNMAP vma that is fully mapped at mmap time */
+#define VM_PAT 0x40000000 /* PAT reserves whole VMA at once (x86) */
#define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */
/* Bits set in the VMA until the stack is in its final location */
@@ -158,24 +158,6 @@ extern pgprot_t protection_map[16];
#define FAULT_FLAG_RETRY_NOWAIT 0x10 /* Don't drop mmap_sem and wait when retrying */
#define FAULT_FLAG_KILLABLE 0x20 /* The fault task is in SIGKILL killable region */
-/*
- * This interface is used by x86 PAT code to identify a pfn mapping that is
- * linear over entire vma. This is to optimize PAT code that deals with
- * marking the physical region with a particular prot. This is not for generic
- * mm use. Note also that this check will not work if the pfn mapping is
- * linear for a vma starting at physical address 0. In which case PAT code
- * falls back to slow path of reserving physical range page by page.
- */
-static inline int is_linear_pfn_mapping(struct vm_area_struct *vma)
-{
- return !!(vma->vm_flags & VM_PFN_AT_MMAP);
-}
-
-static inline int is_pfn_mapping(struct vm_area_struct *vma)
-{
- return !!(vma->vm_flags & VM_PFNMAP);
-}
-
/*
* vm_fault is filled by the the pagefault handler and passed to the vma's
* ->fault function. The vma's ->fault is responsible for returning a bitmask
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 141dbb695097c1f0674b8978456eb1d0c98e3e67..73cb22ee96654c9c548d397f7b4f621e46721e22 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1655,11 +1655,7 @@ int khugepaged_enter_vma_merge(struct vm_area_struct *vma)
if (vma->vm_ops)
/* khugepaged not yet working on file or special mappings */
return 0;
- /*
- * If is_pfn_mapping() is true is_learn_pfn_mapping() must be
- * true too, verify it here.
- */
- VM_BUG_ON(is_linear_pfn_mapping(vma) || vma->vm_flags & VM_NO_THP);
+ VM_BUG_ON(vma->vm_flags & VM_NO_THP);
hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
hend = vma->vm_end & HPAGE_PMD_MASK;
if (hstart < hend)
@@ -1912,11 +1908,7 @@ static void collapse_huge_page(struct mm_struct *mm,
goto out;
if (is_vma_temporary_stack(vma))
goto out;
- /*
- * If is_pfn_mapping() is true is_learn_pfn_mapping() must be
- * true too, verify it here.
- */
- VM_BUG_ON(is_linear_pfn_mapping(vma) || vma->vm_flags & VM_NO_THP);
+ VM_BUG_ON(vma->vm_flags & VM_NO_THP);
pgd = pgd_offset(mm, address);
if (!pgd_present(*pgd))
@@ -2154,12 +2146,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
goto skip;
if (is_vma_temporary_stack(vma))
goto skip;
- /*
- * If is_pfn_mapping() is true is_learn_pfn_mapping()
- * must be true too, verify it here.
- */
- VM_BUG_ON(is_linear_pfn_mapping(vma) ||
- vma->vm_flags & VM_NO_THP);
+ VM_BUG_ON(vma->vm_flags & VM_NO_THP);
hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
hend = vma->vm_end & HPAGE_PMD_MASK;
diff --git a/mm/memory.c b/mm/memory.c
index 6bef278ad3033868deebcb4256d64349e02aa380..655e1429388a364014899b4a84ea59e97500a5ea 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1055,7 +1055,7 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
if (is_vm_hugetlb_page(vma))
return copy_hugetlb_page_range(dst_mm, src_mm, vma);
- if (unlikely(is_pfn_mapping(vma))) {
+ if (unlikely(vma->vm_flags & VM_PFNMAP)) {
/*
* We do not free on error cases below as remove_vma
* gets called on error from higher level routine
@@ -1327,7 +1327,7 @@ static void unmap_single_vma(struct mmu_gather *tlb,
if (vma->vm_file)
uprobe_munmap(vma, start, end);
- if (unlikely(is_pfn_mapping(vma)))
+ if (unlikely(vma->vm_flags & VM_PFNMAP))
untrack_pfn(vma, 0, 0);
if (start != end) {
@@ -2299,26 +2299,20 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
* There's a horrible special case to handle copy-on-write
* behaviour that some programs depend on. We mark the "original"
* un-COW'ed pages by matching them up with "vma->vm_pgoff".
+ * See vm_normal_page() for details.
*/
- if (addr == vma->vm_start && end == vma->vm_end) {
+ if (is_cow_mapping(vma->vm_flags)) {
+ if (addr != vma->vm_start || end != vma->vm_end)
+ return -EINVAL;
vma->vm_pgoff = pfn;
- vma->vm_flags |= VM_PFN_AT_MMAP;
- } else if (is_cow_mapping(vma->vm_flags))
+ }
+
+ err = track_pfn_remap(vma, &prot, pfn, addr, PAGE_ALIGN(size));
+ if (err)
return -EINVAL;
vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
- err = track_pfn_remap(vma, &prot, pfn, PAGE_ALIGN(size));
- if (err) {
- /*
- * To indicate that track_pfn related cleanup is not
- * needed from higher level routine calling unmap_vmas
- */
- vma->vm_flags &= ~(VM_IO | VM_RESERVED | VM_PFNMAP);
- vma->vm_flags &= ~VM_PFN_AT_MMAP;
- return -EINVAL;
- }
-
BUG_ON(addr >= end);
pfn -= addr >> PAGE_SHIFT;
pgd = pgd_offset(mm, addr);