[PATCH 3/6] dax: Use vmf->pgoff in fault handlers

From: Matthew Wilcox
Date: Sun Jan 31 2016 - 07:21:14 EST


Now that the PMD and PUD fault handlers are passed pgoff, there's no
need to calculate it themselves.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@xxxxxxxxx>
---
fs/dax.c | 26 ++++++++++++--------------
1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/fs/dax.c b/fs/dax.c
index 696ff90..d0e1334 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -709,7 +709,7 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
unsigned long pmd_addr = address & PMD_MASK;
bool write = vmf->flags & FAULT_FLAG_WRITE;
struct block_device *bdev;
- pgoff_t size, pgoff;
+ pgoff_t size;
sector_t block;
int error, result = 0;
bool alloc = false;
@@ -734,12 +734,11 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
return VM_FAULT_FALLBACK;
}

- pgoff = linear_page_index(vma, pmd_addr);
size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
- if (pgoff >= size)
+ if (vmf->pgoff >= size)
return VM_FAULT_SIGBUS;
/* If the PMD would cover blocks out of the file */
- if ((pgoff | PG_PMD_COLOUR) >= size) {
+ if ((vmf->pgoff | PG_PMD_COLOUR) >= size) {
dax_pmd_dbg(NULL, address,
"offset + huge page size > file size");
return VM_FAULT_FALLBACK;
@@ -747,7 +746,7 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf,

memset(&bh, 0, sizeof(bh));
bh.b_bdev = inode->i_sb->s_bdev;
- block = (sector_t)pgoff << (PAGE_SHIFT - blkbits);
+ block = (sector_t)vmf->pgoff << (PAGE_SHIFT - blkbits);

bh.b_size = PMD_SIZE;

@@ -777,7 +776,7 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
* zero pages covering this hole
*/
if (alloc) {
- loff_t lstart = pgoff << PAGE_SHIFT;
+ loff_t lstart = vmf->pgoff << PAGE_SHIFT;
loff_t lend = lstart + PMD_SIZE - 1; /* inclusive */

truncate_pagecache_range(inode, lstart, lend);
@@ -863,8 +862,8 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
* the write to insert a dirty entry.
*/
if (write) {
- error = dax_radix_entry(mapping, pgoff, dax.sector,
- true, true);
+ error = dax_radix_entry(mapping, vmf->pgoff,
+ dax.sector, true, true);
if (error) {
dax_pmd_dbg(&bh, address,
"PMD radix insertion failed");
@@ -921,7 +920,7 @@ static int dax_pud_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
unsigned long pud_addr = address & PUD_MASK;
bool write = vmf->flags & FAULT_FLAG_WRITE;
struct block_device *bdev;
- pgoff_t size, pgoff;
+ pgoff_t size;
sector_t block;
int result = 0;
bool alloc = false;
@@ -946,12 +945,11 @@ static int dax_pud_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
return VM_FAULT_FALLBACK;
}

- pgoff = linear_page_index(vma, pud_addr);
size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
- if (pgoff >= size)
+ if (vmf->pgoff >= size)
return VM_FAULT_SIGBUS;
/* If the PUD would cover blocks out of the file */
- if ((pgoff | PG_PUD_COLOUR) >= size) {
+ if ((vmf->pgoff | PG_PUD_COLOUR) >= size) {
dax_pud_dbg(NULL, address,
"offset + huge page size > file size");
return VM_FAULT_FALLBACK;
@@ -959,7 +957,7 @@ static int dax_pud_fault(struct vm_area_struct *vma, struct vm_fault *vmf,

memset(&bh, 0, sizeof(bh));
bh.b_bdev = inode->i_sb->s_bdev;
- block = (sector_t)pgoff << (PAGE_SHIFT - blkbits);
+ block = (sector_t)vmf->pgoff << (PAGE_SHIFT - blkbits);

bh.b_size = PUD_SIZE;

@@ -989,7 +987,7 @@ static int dax_pud_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
* zero pages covering this hole
*/
if (alloc) {
- loff_t lstart = pgoff << PAGE_SHIFT;
+ loff_t lstart = vmf->pgoff << PAGE_SHIFT;
loff_t lend = lstart + PUD_SIZE - 1; /* inclusive */

truncate_pagecache_range(inode, lstart, lend);
--
2.7.0.rc3