clean up write_begin usage for directories in pagecache

For filesystem that implement directories in pagecache we call
block_write_begin with an already allocated page for this code, while the
normal regular file write path uses the default block_write_begin behaviour.

Get rid of the __foofs_write_begin helper and opencode the normal write_begin
call in foofs_write_begin, while adding a new foofs_prepare_chunk helper for
the directory code.  The added benefit is that foofs_prepare_chunk has
a much saner calling convention.

Note that the interruptible flag passed into block_write_begin is always
ignored if we already pass in a page (see next patch for details), and
we never were doing truncations of exessive blocks for this case either so we
can switch directly to block_write_begin_newtrunc.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Christoph Hellwig
2010-06-04 11:29:56 +02:00
committed by Al Viro
parent 282dc17884
commit f4e420dc42
13 changed files with 57 additions and 107 deletions

View File

@@ -271,8 +271,7 @@ int minix_add_link(struct dentry *dentry, struct inode *inode)
got_it:
pos = page_offset(page) + p - (char *)page_address(page);
err = __minix_write_begin(NULL, page->mapping, pos, sbi->s_dirsize,
AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
err = minix_prepare_chunk(page, pos, sbi->s_dirsize);
if (err)
goto out_unlock;
memcpy (namx, name, namelen);
@@ -297,8 +296,7 @@ out_unlock:
int minix_delete_entry(struct minix_dir_entry *de, struct page *page)
{
struct address_space *mapping = page->mapping;
struct inode *inode = (struct inode*)mapping->host;
struct inode *inode = page->mapping->host;
char *kaddr = page_address(page);
loff_t pos = page_offset(page) + (char*)de - kaddr;
struct minix_sb_info *sbi = minix_sb(inode->i_sb);
@@ -306,8 +304,7 @@ int minix_delete_entry(struct minix_dir_entry *de, struct page *page)
int err;
lock_page(page);
err = __minix_write_begin(NULL, mapping, pos, len,
AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
err = minix_prepare_chunk(page, pos, len);
if (err == 0) {
if (sbi->s_version == MINIX_V3)
((minix3_dirent *) de)->inode = 0;
@@ -325,16 +322,14 @@ int minix_delete_entry(struct minix_dir_entry *de, struct page *page)
int minix_make_empty(struct inode *inode, struct inode *dir)
{
struct address_space *mapping = inode->i_mapping;
struct page *page = grab_cache_page(mapping, 0);
struct page *page = grab_cache_page(inode->i_mapping, 0);
struct minix_sb_info *sbi = minix_sb(inode->i_sb);
char *kaddr;
int err;
if (!page)
return -ENOMEM;
err = __minix_write_begin(NULL, mapping, 0, 2 * sbi->s_dirsize,
AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
err = minix_prepare_chunk(page, 0, 2 * sbi->s_dirsize);
if (err) {
unlock_page(page);
goto fail;
@@ -425,8 +420,7 @@ not_empty:
void minix_set_link(struct minix_dir_entry *de, struct page *page,
struct inode *inode)
{
struct address_space *mapping = page->mapping;
struct inode *dir = mapping->host;
struct inode *dir = page->mapping->host;
struct minix_sb_info *sbi = minix_sb(dir->i_sb);
loff_t pos = page_offset(page) +
(char *)de-(char*)page_address(page);
@@ -434,8 +428,7 @@ void minix_set_link(struct minix_dir_entry *de, struct page *page,
lock_page(page);
err = __minix_write_begin(NULL, mapping, pos, sbi->s_dirsize,
AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
err = minix_prepare_chunk(page, pos, sbi->s_dirsize);
if (err == 0) {
if (sbi->s_version == MINIX_V3)
((minix3_dirent *) de)->inode = inode->i_ino;

View File

@@ -357,12 +357,10 @@ static int minix_readpage(struct file *file, struct page *page)
return block_read_full_page(page,minix_get_block);
}
int __minix_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
{
return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
minix_get_block);
return block_write_begin_newtrunc(NULL, page->mapping, pos, len, 0,
&page, NULL, minix_get_block);
}
static int minix_write_begin(struct file *file, struct address_space *mapping,
@@ -370,7 +368,8 @@ static int minix_write_begin(struct file *file, struct address_space *mapping,
struct page **pagep, void **fsdata)
{
*pagep = NULL;
return __minix_write_begin(file, mapping, pos, len, flags, pagep, fsdata);
return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
minix_get_block);
}
static sector_t minix_bmap(struct address_space *mapping, sector_t block)

View File

@@ -53,9 +53,7 @@ extern int minix_new_block(struct inode * inode);
extern void minix_free_block(struct inode *inode, unsigned long block);
extern unsigned long minix_count_free_blocks(struct minix_sb_info *sbi);
extern int minix_getattr(struct vfsmount *, struct dentry *, struct kstat *);
extern int __minix_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata);
extern int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len);
extern void V1_minix_truncate(struct inode *);
extern void V2_minix_truncate(struct inode *);