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: Jeff Dike <jdike@xxxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
---
fs/hostfs/hostfs_kern.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index d1abbee281d1..7016653f3e41 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -410,12 +410,12 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc)
struct inode *inode = mapping->host;
char *buffer;
loff_t base = page_offset(page);
- int count = PAGE_CACHE_SIZE;
- int end_index = inode->i_size >> PAGE_CACHE_SHIFT;
+ int count = PAGE_SIZE;
+ int end_index = inode->i_size >> PAGE_SHIFT;
int err;
if (page->index >= end_index)
- count = inode->i_size & (PAGE_CACHE_SIZE-1);
+ count = inode->i_size & (PAGE_SIZE-1);
buffer = kmap(page);
@@ -447,7 +447,7 @@ static int hostfs_readpage(struct file *file, struct page *page)
buffer = kmap(page);
bytes_read = read_file(FILE_HOSTFS_I(file)->fd, &start, buffer,
- PAGE_CACHE_SIZE);
+ PAGE_SIZE);
if (bytes_read < 0) {
ClearPageUptodate(page);
SetPageError(page);
@@ -455,7 +455,7 @@ static int hostfs_readpage(struct file *file, struct page *page)
goto out;
}
- memset(buffer + bytes_read, 0, PAGE_CACHE_SIZE - bytes_read);
+ memset(buffer + bytes_read, 0, PAGE_SIZE - bytes_read);
ClearPageError(page);
SetPageUptodate(page);
@@ -471,7 +471,7 @@ static int hostfs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
- pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+ pgoff_t index = pos >> PAGE_SHIFT;
*pagep = grab_cache_page_write_begin(mapping, index, flags);
if (!*pagep)
@@ -485,14 +485,14 @@ static int hostfs_write_end(struct file *file, struct address_space *mapping,
{
struct inode *inode = mapping->host;
void *buffer;
- unsigned from = pos & (PAGE_CACHE_SIZE - 1);
+ unsigned from = pos & (PAGE_SIZE - 1);
int err;
buffer = kmap(page);
err = write_file(FILE_HOSTFS_I(file)->fd, &pos, buffer + from, copied);
kunmap(page);
- if (!PageUptodate(page) && err == PAGE_CACHE_SIZE)
+ if (!PageUptodate(page) && err == PAGE_SIZE)
SetPageUptodate(page);
/*
@@ -502,7 +502,7 @@ static int hostfs_write_end(struct file *file, struct address_space *mapping,
if (err > 0 && (pos > inode->i_size))
inode->i_size = pos;
unlock_page(page);
- page_cache_release(page);
+ put_page(page);
return err;
}
--
2.7.0
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