[PATCH 64/71] xfs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

From: Kirill A. Shutemov
Date: Sun Mar 20 2016 - 14:47:43 EST


PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago
with promise that one day it will be possible to implement page cache with
bigger chunks than PAGE_SIZE.

This promise never materialized. And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_*
or PAGE_* constant should be used in a particular case, especially on the
border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special. They are not.

The changes are pretty straight-forward:

- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

- page_cache_get() -> get_page();

- page_cache_release() -> put_page();

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
---
fs/xfs/libxfs/xfs_bmap.c | 4 ++--
fs/xfs/xfs_aops.c | 38 +++++++++++++++++++-------------------
fs/xfs/xfs_bmap_util.c | 4 ++--
fs/xfs/xfs_file.c | 12 ++++++------
fs/xfs/xfs_linux.h | 2 +-
fs/xfs/xfs_mount.c | 2 +-
fs/xfs/xfs_mount.h | 4 ++--
fs/xfs/xfs_pnfs.c | 4 ++--
fs/xfs/xfs_super.c | 8 ++++----
9 files changed, 39 insertions(+), 39 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index ef00156f4f96..aafecc12a8e2 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -3745,11 +3745,11 @@ xfs_bmap_btalloc(
args.prod = align;
if ((args.mod = (xfs_extlen_t)do_mod(ap->offset, args.prod)))
args.mod = (xfs_extlen_t)(args.prod - args.mod);
- } else if (mp->m_sb.sb_blocksize >= PAGE_CACHE_SIZE) {
+ } else if (mp->m_sb.sb_blocksize >= PAGE_SIZE) {
args.prod = 1;
args.mod = 0;
} else {
- args.prod = PAGE_CACHE_SIZE >> mp->m_sb.sb_blocklog;
+ args.prod = PAGE_SIZE >> mp->m_sb.sb_blocklog;
if ((args.mod = (xfs_extlen_t)(do_mod(ap->offset, args.prod))))
args.mod = (xfs_extlen_t)(args.prod - args.mod);
}
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 5c57b7b40728..d12dfcfd0cc8 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -719,14 +719,14 @@ xfs_convert_page(
* Derivation:
*
* End offset is the highest offset that this page should represent.
- * If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1))
- * will evaluate non-zero and be less than PAGE_CACHE_SIZE and
+ * If we are on the last page, (end_offset & (PAGE_SIZE - 1))
+ * will evaluate non-zero and be less than PAGE_SIZE and
* hence give us the correct page_dirty count. On any other page,
* it will be zero and in that case we need page_dirty to be the
* count of buffers on the page.
*/
end_offset = min_t(unsigned long long,
- (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
+ (xfs_off_t)(page->index + 1) << PAGE_SHIFT,
i_size_read(inode));

/*
@@ -749,9 +749,9 @@ xfs_convert_page(
goto fail_unlock_page;

len = 1 << inode->i_blkbits;
- p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
- PAGE_CACHE_SIZE);
- p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
+ p_offset = min_t(unsigned long, end_offset & (PAGE_SIZE - 1),
+ PAGE_SIZE);
+ p_offset = p_offset ? roundup(p_offset, len) : PAGE_SIZE;
page_dirty = p_offset / len;

/*
@@ -927,7 +927,7 @@ next_buffer:

xfs_iunlock(ip, XFS_ILOCK_EXCL);
out_invalidate:
- xfs_vm_invalidatepage(page, 0, PAGE_CACHE_SIZE);
+ xfs_vm_invalidatepage(page, 0, PAGE_SIZE);
return;
}

@@ -984,8 +984,8 @@ xfs_vm_writepage(

/* Is this page beyond the end of the file? */
offset = i_size_read(inode);
- end_index = offset >> PAGE_CACHE_SHIFT;
- last_index = (offset - 1) >> PAGE_CACHE_SHIFT;
+ end_index = offset >> PAGE_SHIFT;
+ last_index = (offset - 1) >> PAGE_SHIFT;

/*
* The page index is less than the end_index, adjust the end_offset
@@ -999,7 +999,7 @@ xfs_vm_writepage(
* ---------------------------------^------------------|
*/
if (page->index < end_index)
- end_offset = (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT;
+ end_offset = (xfs_off_t)(page->index + 1) << PAGE_SHIFT;
else {
/*
* Check whether the page to write out is beyond or straddles
@@ -1012,7 +1012,7 @@ xfs_vm_writepage(
* | | Straddles |
* ---------------------------------^-----------|--------|
*/
- unsigned offset_into_page = offset & (PAGE_CACHE_SIZE - 1);
+ unsigned offset_into_page = offset & (PAGE_SIZE - 1);

/*
* Skip the page if it is fully outside i_size, e.g. due to a
@@ -1043,7 +1043,7 @@ xfs_vm_writepage(
* memory is zeroed when mapped, and writes to that region are
* not written out to the file."
*/
- zero_user_segment(page, offset_into_page, PAGE_CACHE_SIZE);
+ zero_user_segment(page, offset_into_page, PAGE_SIZE);

/* Adjust the end_offset to the end of file */
end_offset = offset;
@@ -1162,7 +1162,7 @@ xfs_vm_writepage(
end_index <<= inode->i_blkbits;

/* to pages */
- end_index = (end_index - 1) >> PAGE_CACHE_SHIFT;
+ end_index = (end_index - 1) >> PAGE_SHIFT;

/* check against file size */
if (end_index > last_index)
@@ -1753,7 +1753,7 @@ xfs_vm_write_failed(
loff_t block_offset;
loff_t block_start;
loff_t block_end;
- loff_t from = pos & (PAGE_CACHE_SIZE - 1);
+ loff_t from = pos & (PAGE_SIZE - 1);
loff_t to = from + len;
struct buffer_head *bh, *head;

@@ -1768,7 +1768,7 @@ xfs_vm_write_failed(
* start of the page by using shifts rather than masks the mismatch
* problem.
*/
- block_offset = (pos >> PAGE_CACHE_SHIFT) << PAGE_CACHE_SHIFT;
+ block_offset = (pos >> PAGE_SHIFT) << PAGE_SHIFT;

ASSERT(block_offset + from == pos);

@@ -1825,11 +1825,11 @@ xfs_vm_write_begin(
struct page **pagep,
void **fsdata)
{
- pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+ pgoff_t index = pos >> PAGE_SHIFT;
struct page *page;
int status;

- ASSERT(len <= PAGE_CACHE_SIZE);
+ ASSERT(len <= PAGE_SIZE);

page = grab_cache_page_write_begin(mapping, index, flags);
if (!page)
@@ -1854,7 +1854,7 @@ xfs_vm_write_begin(
truncate_pagecache_range(inode, start, pos + len);
}

- page_cache_release(page);
+ put_page(page);
page = NULL;
}

@@ -1882,7 +1882,7 @@ xfs_vm_write_end(
{
int ret;

- ASSERT(len <= PAGE_CACHE_SIZE);
+ ASSERT(len <= PAGE_SIZE);

ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
if (unlikely(ret < len)) {
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 6c876012b2e5..d788858da5e1 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1235,7 +1235,7 @@ xfs_free_file_space(
/* wait for the completion of any pending DIOs */
inode_dio_wait(VFS_I(ip));

- rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE);
+ rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_SIZE);
ioffset = round_down(offset, rounding);
iendoffset = round_up(offset + len, rounding) - 1;
error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, ioffset,
@@ -1464,7 +1464,7 @@ xfs_shift_file_space(
if (error)
return error;
error = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
- offset >> PAGE_CACHE_SHIFT, -1);
+ offset >> PAGE_SHIFT, -1);
if (error)
return error;

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 52883ac3cf84..aab748adf273 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -106,8 +106,8 @@ xfs_iozero(
unsigned offset, bytes;
void *fsdata;

- offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
- bytes = PAGE_CACHE_SIZE - offset;
+ offset = (pos & (PAGE_SIZE -1)); /* Within page */
+ bytes = PAGE_SIZE - offset;
if (bytes > count)
bytes = count;

@@ -799,8 +799,8 @@ xfs_file_dio_aio_write(
/* see generic_file_direct_write() for why this is necessary */
if (mapping->nrpages) {
invalidate_inode_pages2_range(mapping,
- pos >> PAGE_CACHE_SHIFT,
- end >> PAGE_CACHE_SHIFT);
+ pos >> PAGE_SHIFT,
+ end >> PAGE_SHIFT);
}

if (ret > 0) {
@@ -1207,9 +1207,9 @@ xfs_find_get_desired_pgoff(

pagevec_init(&pvec, 0);

- index = startoff >> PAGE_CACHE_SHIFT;
+ index = startoff >> PAGE_SHIFT;
endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
- end = endoff >> PAGE_CACHE_SHIFT;
+ end = endoff >> PAGE_SHIFT;
do {
int want;
unsigned nr_pages;
diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
index ec0e239a0fa9..a8192dc797dc 100644
--- a/fs/xfs/xfs_linux.h
+++ b/fs/xfs/xfs_linux.h
@@ -135,7 +135,7 @@ typedef __u32 xfs_nlink_t;
* Size of block device i/o is parameterized here.
* Currently the system supports page-sized i/o.
*/
-#define BLKDEV_IOSHIFT PAGE_CACHE_SHIFT
+#define BLKDEV_IOSHIFT PAGE_SHIFT
#define BLKDEV_IOSIZE (1<<BLKDEV_IOSHIFT)
/* number of BB's per block device block */
#define BLKDEV_BB BTOBB(BLKDEV_IOSIZE)
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index bb753b359bee..9091e2fe1e0c 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -171,7 +171,7 @@ xfs_sb_validate_fsb_count(
ASSERT(sbp->sb_blocklog >= BBSHIFT);

/* Limited by ULONG_MAX of page cache index */
- if (nblocks >> (PAGE_CACHE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
+ if (nblocks >> (PAGE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
return -EFBIG;
return 0;
}
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index b57098481c10..cd2cb5ef4c08 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -221,12 +221,12 @@ static inline unsigned long
xfs_preferred_iosize(xfs_mount_t *mp)
{
if (mp->m_flags & XFS_MOUNT_COMPAT_IOSIZE)
- return PAGE_CACHE_SIZE;
+ return PAGE_SIZE;
return (mp->m_swidth ?
(mp->m_swidth << mp->m_sb.sb_blocklog) :
((mp->m_flags & XFS_MOUNT_DFLT_IOSIZE) ?
(1 << (int)MAX(mp->m_readio_log, mp->m_writeio_log)) :
- PAGE_CACHE_SIZE));
+ PAGE_SIZE));
}

#define XFS_LAST_UNMOUNT_WAS_CLEAN(mp) \
diff --git a/fs/xfs/xfs_pnfs.c b/fs/xfs/xfs_pnfs.c
index ade236e90bb3..51ddaf2c2b8c 100644
--- a/fs/xfs/xfs_pnfs.c
+++ b/fs/xfs/xfs_pnfs.c
@@ -293,8 +293,8 @@ xfs_fs_commit_blocks(
* Make sure reads through the pagecache see the new data.
*/
error = invalidate_inode_pages2_range(inode->i_mapping,
- start >> PAGE_CACHE_SHIFT,
- (end - 1) >> PAGE_CACHE_SHIFT);
+ start >> PAGE_SHIFT,
+ (end - 1) >> PAGE_SHIFT);
WARN_ON_ONCE(error);

error = xfs_iomap_write_unwritten(ip, start, length);
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 59c9b7bd958d..89f1d5e064a9 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -547,10 +547,10 @@ xfs_max_file_offset(
/* Figure out maximum filesize, on Linux this can depend on
* the filesystem blocksize (on 32 bit platforms).
* __block_write_begin does this in an [unsigned] long...
- * page->index << (PAGE_CACHE_SHIFT - bbits)
+ * page->index << (PAGE_SHIFT - bbits)
* So, for page sized blocks (4K on 32 bit platforms),
* this wraps at around 8Tb (hence MAX_LFS_FILESIZE which is
- * (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
+ * (((u64)PAGE_SIZE << (BITS_PER_LONG-1))-1)
* but for smaller blocksizes it is less (bbits = log2 bsize).
* Note1: get_block_t takes a long (implicit cast from above)
* Note2: The Large Block Device (LBD and HAVE_SECTOR_T) patch
@@ -561,10 +561,10 @@ xfs_max_file_offset(
#if BITS_PER_LONG == 32
# if defined(CONFIG_LBDAF)
ASSERT(sizeof(sector_t) == 8);
- pagefactor = PAGE_CACHE_SIZE;
+ pagefactor = PAGE_SIZE;
bitshift = BITS_PER_LONG;
# else
- pagefactor = PAGE_CACHE_SIZE >> (PAGE_CACHE_SHIFT - blockshift);
+ pagefactor = PAGE_SIZE >> (PAGE_SHIFT - blockshift);
# endif
#endif

--
2.7.0