[PATCH] mm: introduce __linear_page_index()
From: Huang Shijie
Date: Tue Feb 05 2013 - 03:03:27 EST
There are many places we should get the offset(in PAGE_SIZE unit) of
an address within a non-hugetlb vma.
In order to simplify the code, add a new helper __linear_page_index()
to do the work.
Signed-off-by: Huang Shijie <b32955@xxxxxxxxxxxxx>
---
This patch is based on linux-next tree.
---
arch/arm/mm/fault-armv.c | 2 +-
arch/powerpc/kvm/book3s_64_mmu_hv.c | 5 ++---
arch/x86/mm/hugetlbpage.c | 3 +--
include/linux/pagemap.h | 16 ++++++++++++----
ipc/shm.c | 7 ++-----
mm/hugetlb.c | 3 +--
mm/madvise.c | 8 ++++----
mm/memory.c | 10 +++-------
mm/mempolicy.c | 6 ++----
mm/mlock.c | 2 +-
mm/mprotect.c | 2 +-
mm/mremap.c | 14 +++++---------
mm/shmem.c | 5 ++---
virt/kvm/kvm_main.c | 3 +--
14 files changed, 38 insertions(+), 48 deletions(-)
diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c
index 2a5907b..f50df8a 100644
--- a/arch/arm/mm/fault-armv.c
+++ b/arch/arm/mm/fault-armv.c
@@ -138,7 +138,7 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma,
pgoff_t pgoff;
int aliases = 0;
- pgoff = vma->vm_pgoff + ((addr - vma->vm_start) >> PAGE_SHIFT);
+ pgoff = __linear_page_index(vma, addr);
/*
* If we have any shared mappings that are in the same mm
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 8cc18ab..a4a893b 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -310,7 +310,7 @@ static long kvmppc_get_guest_page(struct kvm *kvm, unsigned long gfn,
!(vma->vm_flags & VM_PFNMAP))
goto up_err;
is_io = hpte_cache_bits(pgprot_val(vma->vm_page_prot));
- pfn = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
+ pfn = __linear_page_index(vma, start);
/* check alignment of pfn vs. requested page size */
if (psize > PAGE_SIZE && (pfn & ((psize >> PAGE_SHIFT) - 1)))
goto up_err;
@@ -658,8 +658,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
vma = find_vma(current->mm, hva);
if (vma && vma->vm_start <= hva && hva + psize <= vma->vm_end &&
(vma->vm_flags & VM_PFNMAP)) {
- pfn = vma->vm_pgoff +
- ((hva - vma->vm_start) >> PAGE_SHIFT);
+ pfn = __linear_page_index(vma, hva);
pte_size = psize;
is_io = hpte_cache_bits(pgprot_val(vma->vm_page_prot));
write_ok = vma->vm_flags & VM_WRITE;
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index ae1aa71..5dfcd5b 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -69,8 +69,7 @@ huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
{
struct vm_area_struct *vma = find_vma(mm, addr);
struct address_space *mapping = vma->vm_file->f_mapping;
- pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
- vma->vm_pgoff;
+ pgoff_t idx = __linear_page_index(vma, addr);
struct vm_area_struct *svma;
unsigned long saddr;
pte_t *spte = NULL;
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 0e38e13..03e442a 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -310,15 +310,23 @@ static inline loff_t page_file_offset(struct page *page)
extern pgoff_t linear_hugepage_index(struct vm_area_struct *vma,
unsigned long address);
-static inline pgoff_t linear_page_index(struct vm_area_struct *vma,
+/* The offset for an address within a non-hugetlb vma, in PAGE_SIZE unit. */
+static inline pgoff_t __linear_page_index(struct vm_area_struct *vma,
unsigned long address)
{
pgoff_t pgoff;
+
+ pgoff = (address - vma->vm_start) >> PAGE_SHIFT;
+ return pgoff + vma->vm_pgoff;
+}
+
+static inline pgoff_t linear_page_index(struct vm_area_struct *vma,
+ unsigned long address)
+{
if (unlikely(is_vm_hugetlb_page(vma)))
return linear_hugepage_index(vma, address);
- pgoff = (address - vma->vm_start) >> PAGE_SHIFT;
- pgoff += vma->vm_pgoff;
- return pgoff >> (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+ return __linear_page_index(vma, address) >>
+ (PAGE_CACHE_SHIFT - PAGE_SHIFT);
}
extern void __lock_page(struct page *page);
diff --git a/ipc/shm.c b/ipc/shm.c
index be3ec9a..77b7d02 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1172,9 +1172,7 @@ SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
* otherwise it starts at this address with no hassles.
*/
if ((vma->vm_ops == &shm_vm_ops) &&
- (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) {
-
-
+ 0 == __linear_page_index(vma, addr)) {
size = vma->vm_file->f_path.dentry->d_inode->i_size;
do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
/*
@@ -1201,8 +1199,7 @@ SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
/* finding a matching vma now does not alter retval */
if ((vma->vm_ops == &shm_vm_ops) &&
- (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff)
-
+ 0 == __linear_page_index(vma, addr))
do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
vma = next;
}
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index e14a8c7..756bf6e 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2477,8 +2477,7 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
* from page cache lookup which is in HPAGE_SIZE units.
*/
address = address & huge_page_mask(h);
- pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) +
- vma->vm_pgoff;
+ pgoff = __linear_page_index(vma, address);
mapping = vma->vm_file->f_dentry->d_inode->i_mapping;
/*
diff --git a/mm/madvise.c b/mm/madvise.c
index c58c94b..51bfaf2 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -100,7 +100,7 @@ static long madvise_behavior(struct vm_area_struct * vma,
goto out;
}
- pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
+ pgoff = __linear_page_index(vma, start);
*prev = vma_merge(mm, *prev, start, end, new_flags, vma->anon_vma,
vma->vm_file, pgoff, vma_policy(vma));
if (*prev) {
@@ -193,7 +193,7 @@ static void force_shm_swapin_readahead(struct vm_area_struct *vma,
swp_entry_t swap;
for (; start < end; start += PAGE_SIZE) {
- index = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+ index = __linear_page_index(vma, start);
page = find_get_page(mapping, index);
if (!radix_tree_exceptional_entry(page)) {
@@ -242,10 +242,10 @@ static long madvise_willneed(struct vm_area_struct * vma,
}
*prev = vma;
- start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+ start = __linear_page_index(vma, start);
if (end > vma->vm_end)
end = vma->vm_end;
- end = ((end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+ end = __linear_page_index(vma, end);
force_page_cache_readahead(file->f_mapping, file, start, end - start);
return 0;
diff --git a/mm/memory.c b/mm/memory.c
index c04078b..b7e4f04 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -798,9 +798,7 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
return NULL;
goto out;
} else {
- unsigned long off;
- off = (addr - vma->vm_start) >> PAGE_SHIFT;
- if (pfn == vma->vm_pgoff + off)
+ if (pfn == __linear_page_index(vma, addr))
return NULL;
if (!is_cow_mapping(vma->vm_flags))
return NULL;
@@ -3404,11 +3402,9 @@ static int do_linear_fault(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pte_t *page_table, pmd_t *pmd,
unsigned int flags, pte_t orig_pte)
{
- pgoff_t pgoff = (((address & PAGE_MASK)
- - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
-
pte_unmap(page_table);
- return __do_fault(mm, vma, address, pmd, pgoff, flags, orig_pte);
+ return __do_fault(mm, vma, address, pmd,
+ __linear_page_index(vma, address), flags, orig_pte);
}
/*
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 6f7979c..870f40a 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -725,8 +725,7 @@ static int mbind_range(struct mm_struct *mm, unsigned long start,
if (mpol_equal(vma_policy(vma), new_pol))
continue;
- pgoff = vma->vm_pgoff +
- ((vmstart - vma->vm_start) >> PAGE_SHIFT);
+ pgoff = __linear_page_index(vma, vmstart);
prev = vma_merge(mm, prev, vmstart, vmend, vma->vm_flags,
vma->anon_vma, vma->vm_file, pgoff,
new_pol);
@@ -2257,8 +2256,7 @@ int mpol_misplaced(struct page *page, struct vm_area_struct *vma, unsigned long
BUG_ON(addr >= vma->vm_end);
BUG_ON(addr < vma->vm_start);
- pgoff = vma->vm_pgoff;
- pgoff += (addr - vma->vm_start) >> PAGE_SHIFT;
+ pgoff = __linear_page_index(vma, addr);
polnid = offset_il_node(pol, vma, pgoff);
break;
diff --git a/mm/mlock.c b/mm/mlock.c
index b1647fb..fb62a2e 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -269,7 +269,7 @@ static int mlock_fixup(struct vm_area_struct *vma, struct vm_area_struct **prev,
is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm))
goto out; /* don't set VM_LOCKED, don't count */
- pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
+ pgoff = __linear_page_index(vma, start);
*prev = vma_merge(mm, *prev, start, end, newflags, vma->anon_vma,
vma->vm_file, pgoff, vma_policy(vma));
if (*prev) {
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 94722a4..c9d57f0 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -269,7 +269,7 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev,
/*
* First try to merge with previous and/or next vma.
*/
- pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
+ pgoff = __linear_page_index(vma, start);
*pprev = vma_merge(mm, *pprev, start, end, newflags,
vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma));
if (*pprev) {
diff --git a/mm/mremap.c b/mm/mremap.c
index 38fffd8..640c616 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -240,7 +240,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
if (err)
return err;
- new_pgoff = vma->vm_pgoff + ((old_addr - vma->vm_start) >> PAGE_SHIFT);
+ new_pgoff = __linear_page_index(vma, old_addr);
new_vma = copy_vma(&vma, new_addr, new_len, new_pgoff,
&need_rmap_locks);
if (!new_vma)
@@ -327,8 +327,7 @@ static struct vm_area_struct *vma_to_resize(unsigned long addr,
if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP))
goto Efault;
- pgoff = (addr - vma->vm_start) >> PAGE_SHIFT;
- pgoff += vma->vm_pgoff;
+ pgoff = __linear_page_index(vma, addr);
if (pgoff + (new_len >> PAGE_SHIFT) < pgoff)
goto Einval;
}
@@ -409,9 +408,8 @@ static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
if (vma->vm_flags & VM_MAYSHARE)
map_flags |= MAP_SHARED;
- ret = get_unmapped_area(vma->vm_file, new_addr, new_len, vma->vm_pgoff +
- ((addr - vma->vm_start) >> PAGE_SHIFT),
- map_flags);
+ ret = get_unmapped_area(vma->vm_file, new_addr, new_len,
+ __linear_page_index(vma, addr), map_flags);
if (ret & ~PAGE_MASK)
goto out1;
@@ -538,9 +536,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
map_flags |= MAP_SHARED;
new_addr = get_unmapped_area(vma->vm_file, 0, new_len,
- vma->vm_pgoff +
- ((addr - vma->vm_start) >> PAGE_SHIFT),
- map_flags);
+ __linear_page_index(vma, addr), map_flags);
if (new_addr & ~PAGE_MASK) {
ret = new_addr;
goto out;
diff --git a/mm/shmem.c b/mm/shmem.c
index 3049cfc..50e1b38 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1322,10 +1322,9 @@ static struct mempolicy *shmem_get_policy(struct vm_area_struct *vma,
unsigned long addr)
{
struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
- pgoff_t index;
- index = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
- return mpol_shared_policy_lookup(&SHMEM_I(inode)->policy, index);
+ return mpol_shared_policy_lookup(&SHMEM_I(inode)->policy,
+ __linear_page_index(vma, addr));
}
#endif
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c94088d..fbbfaf1 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1240,8 +1240,7 @@ static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
if (vma == NULL)
pfn = KVM_PFN_ERR_FAULT;
else if ((vma->vm_flags & VM_PFNMAP)) {
- pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
- vma->vm_pgoff;
+ pfn = __linear_page_index(vma, addr);
BUG_ON(!kvm_is_mmio_pfn(pfn));
} else {
if (async && vma_is_valid(vma, write_fault))
--
1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/