[PATCH 32/71] ext2: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
From: Kirill A. Shutemov
Date: Sun Mar 20 2016 - 14:54:16 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: Jan Kara <jack@xxxxxxxx>
---
fs/ext2/dir.c | 36 ++++++++++++++++++------------------
fs/ext2/namei.c | 6 +++---
2 files changed, 21 insertions(+), 21 deletions(-)
diff --git a/fs/ext2/dir.c b/fs/ext2/dir.c
index 0c6638b40f21..7ff6fcfa685d 100644
--- a/fs/ext2/dir.c
+++ b/fs/ext2/dir.c
@@ -37,7 +37,7 @@ static inline unsigned ext2_rec_len_from_disk(__le16 dlen)
{
unsigned len = le16_to_cpu(dlen);
-#if (PAGE_CACHE_SIZE >= 65536)
+#if (PAGE_SIZE >= 65536)
if (len == EXT2_MAX_REC_LEN)
return 1 << 16;
#endif
@@ -46,7 +46,7 @@ static inline unsigned ext2_rec_len_from_disk(__le16 dlen)
static inline __le16 ext2_rec_len_to_disk(unsigned len)
{
-#if (PAGE_CACHE_SIZE >= 65536)
+#if (PAGE_SIZE >= 65536)
if (len == (1 << 16))
return cpu_to_le16(EXT2_MAX_REC_LEN);
else
@@ -67,7 +67,7 @@ static inline unsigned ext2_chunk_size(struct inode *inode)
static inline void ext2_put_page(struct page *page)
{
kunmap(page);
- page_cache_release(page);
+ put_page(page);
}
/*
@@ -79,9 +79,9 @@ ext2_last_byte(struct inode *inode, unsigned long page_nr)
{
unsigned last_byte = inode->i_size;
- last_byte -= page_nr << PAGE_CACHE_SHIFT;
- if (last_byte > PAGE_CACHE_SIZE)
- last_byte = PAGE_CACHE_SIZE;
+ last_byte -= page_nr << PAGE_SHIFT;
+ if (last_byte > PAGE_SIZE)
+ last_byte = PAGE_SIZE;
return last_byte;
}
@@ -118,12 +118,12 @@ static void ext2_check_page(struct page *page, int quiet)
char *kaddr = page_address(page);
u32 max_inumber = le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count);
unsigned offs, rec_len;
- unsigned limit = PAGE_CACHE_SIZE;
+ unsigned limit = PAGE_SIZE;
ext2_dirent *p;
char *error;
- if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
- limit = dir->i_size & ~PAGE_CACHE_MASK;
+ if ((dir->i_size >> PAGE_SHIFT) == page->index) {
+ limit = dir->i_size & ~PAGE_MASK;
if (limit & (chunk_size - 1))
goto Ebadsize;
if (!limit)
@@ -176,7 +176,7 @@ bad_entry:
if (!quiet)
ext2_error(sb, __func__, "bad entry in directory #%lu: : %s - "
"offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
- dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
+ dir->i_ino, error, (page->index<<PAGE_SHIFT)+offs,
(unsigned long) le32_to_cpu(p->inode),
rec_len, p->name_len);
goto fail;
@@ -186,7 +186,7 @@ Eend:
ext2_error(sb, "ext2_check_page",
"entry in directory #%lu spans the page boundary"
"offset=%lu, inode=%lu",
- dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
+ dir->i_ino, (page->index<<PAGE_SHIFT)+offs,
(unsigned long) le32_to_cpu(p->inode));
}
fail:
@@ -287,8 +287,8 @@ ext2_readdir(struct file *file, struct dir_context *ctx)
loff_t pos = ctx->pos;
struct inode *inode = file_inode(file);
struct super_block *sb = inode->i_sb;
- unsigned int offset = pos & ~PAGE_CACHE_MASK;
- unsigned long n = pos >> PAGE_CACHE_SHIFT;
+ unsigned int offset = pos & ~PAGE_MASK;
+ unsigned long n = pos >> PAGE_SHIFT;
unsigned long npages = dir_pages(inode);
unsigned chunk_mask = ~(ext2_chunk_size(inode)-1);
unsigned char *types = NULL;
@@ -309,14 +309,14 @@ ext2_readdir(struct file *file, struct dir_context *ctx)
ext2_error(sb, __func__,
"bad page in #%lu",
inode->i_ino);
- ctx->pos += PAGE_CACHE_SIZE - offset;
+ ctx->pos += PAGE_SIZE - offset;
return PTR_ERR(page);
}
kaddr = page_address(page);
if (unlikely(need_revalidate)) {
if (offset) {
offset = ext2_validate_entry(kaddr, offset, chunk_mask);
- ctx->pos = (n<<PAGE_CACHE_SHIFT) + offset;
+ ctx->pos = (n<<PAGE_SHIFT) + offset;
}
file->f_version = inode->i_version;
need_revalidate = 0;
@@ -406,7 +406,7 @@ struct ext2_dir_entry_2 *ext2_find_entry (struct inode * dir,
if (++n >= npages)
n = 0;
/* next page is past the blocks we've got */
- if (unlikely(n > (dir->i_blocks >> (PAGE_CACHE_SHIFT - 9)))) {
+ if (unlikely(n > (dir->i_blocks >> (PAGE_SHIFT - 9)))) {
ext2_error(dir->i_sb, __func__,
"dir %lu size %lld exceeds block count %llu",
dir->i_ino, dir->i_size,
@@ -511,7 +511,7 @@ int ext2_add_link (struct dentry *dentry, struct inode *inode)
kaddr = page_address(page);
dir_end = kaddr + ext2_last_byte(dir, n);
de = (ext2_dirent *)kaddr;
- kaddr += PAGE_CACHE_SIZE - reclen;
+ kaddr += PAGE_SIZE - reclen;
while ((char *)de <= kaddr) {
if ((char *)de == dir_end) {
/* We hit i_size */
@@ -655,7 +655,7 @@ int ext2_make_empty(struct inode *inode, struct inode *parent)
kunmap_atomic(kaddr);
err = ext2_commit_chunk(page, 0, chunk_size);
fail:
- page_cache_release(page);
+ put_page(page);
return err;
}
diff --git a/fs/ext2/namei.c b/fs/ext2/namei.c
index 7a2be8f7f3c3..d34843925b23 100644
--- a/fs/ext2/namei.c
+++ b/fs/ext2/namei.c
@@ -398,7 +398,7 @@ static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
else {
kunmap(dir_page);
- page_cache_release(dir_page);
+ put_page(dir_page);
}
inode_dec_link_count(old_dir);
}
@@ -408,11 +408,11 @@ static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
out_dir:
if (dir_de) {
kunmap(dir_page);
- page_cache_release(dir_page);
+ put_page(dir_page);
}
out_old:
kunmap(old_page);
- page_cache_release(old_page);
+ put_page(old_page);
out:
return err;
}
--
2.7.0