[PATCH 16/17] ufs: convert ufs_get_page to read_kmap_page

Nate Diller
2007-04-12T02:54:10Z

Replace ufs_get_page()/ufs_get_locked_page() and
ufs_put_page()/ufs_put_locked_page() using the new read_kmap_page() and
put_kmapped_page() calls and their locking variants. Also, change the
ufs_check_page() call to return the page's error status, and update the
call sites accordingly.

Signed-off-by: Nate Diller <nate.diller@gmail.com>

---

diff -urpN -X dontdiff linux-2.6.21-rc5-mm4/fs/ufs/balloc.c linux-2.6.21-rc5-mm4-test/fs/ufs/balloc.c
--- linux-2.6.21-rc5-mm4/fs/ufs/balloc.c 2007-04-05 17:13:29.000000000 -0700
+++ linux-2.6.21-rc5-mm4-test/fs/ufs/balloc.c 2007-04-06 12:46:02.000000000 -0700
@@ -272,7 +272,7 @@ static void ufs_change_blocknr(struct in
index = i >> (PAGE_CACHE_SHIFT - inode->i_blkbits);

if (likely(cur_index != index)) {
- page = ufs_get_locked_page(mapping, index);
+ page = __read_mapping_page(mapping, index, NULL);
if (!page)/* it was truncated */
continue;
if (IS_ERR(page)) {/* or EIO */
@@ -325,8 +325,10 @@ static void ufs_change_blocknr(struct in
bh = bh->b_this_page;
} while (bh != head);

- if (likely(cur_index != index))
- ufs_put_locked_page(page);
+ if (likely(cur_index != index)) {
+ unlock_page(page);
+ page_cache_release(page);
+ }
}
UFSD("EXIT\n");
}
diff -urpN -X dontdiff linux-2.6.21-rc5-mm4/fs/ufs/truncate.c linux-2.6.21-rc5-mm4-test/fs/ufs/truncate.c
--- linux-2.6.21-rc5-mm4/fs/ufs/truncate.c 2007-04-05 17:13:29.000000000 -0700
+++ linux-2.6.21-rc5-mm4-test/fs/ufs/truncate.c 2007-04-06 12:46:14.000000000 -0700
@@ -395,8 +395,9 @@ static int ufs_alloc_lastblock(struct in

lastfrag--;

- lastpage = ufs_get_locked_page(mapping, lastfrag >>
- (PAGE_CACHE_SHIFT - inode->i_blkbits));
+ lastpage = __read_mapping_page(mapping, lastfrag >>
+ (PAGE_CACHE_SHIFT - inode->i_blkbits),
+ NULL);
if (IS_ERR(lastpage)) {
err = -EIO;
goto out;
@@ -441,7 +442,8 @@ static int ufs_alloc_lastblock(struct in
}
}
out_unlock:
- ufs_put_locked_page(lastpage);
+ unlock_page(lastpage);
+ page_cache_release(lastpage);
out:
return err;
}
diff -urpN -X dontdiff linux-2.6.21-rc5-mm4/fs/ufs/util.c linux-2.6.21-rc5-mm4-test/fs/ufs/util.c
--- linux-2.6.21-rc5-mm4/fs/ufs/util.c 2007-04-05 17:14:25.000000000 -0700
+++ linux-2.6.21-rc5-mm4-test/fs/ufs/util.c 2007-04-06 12:40:53.000000000 -0700
@@ -232,55 +232,3 @@ ufs_set_inode_dev(struct super_block *sb
ufsi->i_u1.i_data[0] = cpu_to_fs32(sb, fs32);
}

-/**
- * ufs_get_locked_page() - locate, pin and lock a pagecache page, if not exist
- * read it from disk.
- * @mapping: the address_space to search
- * @index: the page index
- *
- * Locates the desired pagecache page, if not exist we'll read it,
- * locks it, increments its reference
- * count and returns its address.
- *
- */
-
-struct page *ufs_get_locked_page(struct address_space *mapping,
- pgoff_t index)
-{
- struct page *page;
-
- page = find_lock_page(mapping, index);
- if (!page) {
- page = read_mapping_page(mapping, index, NULL);
-
- if (IS_ERR(page)) {
- printk(KERN_ERR "ufs_change_blocknr: "
- "read_mapping_page error: ino %lu, index: %lu\n",
- mapping->host->i_ino, index);
- goto out;
- }
-
- lock_page(page);
-
- if (unlikely(page->mapping == NULL)) {
- /* Truncate got there first */
- unlock_page(page);
- page_cache_release(page);
- page = NULL;
- goto out;
- }
-
- if (!PageUptodate(page) || PageError(page)) {
- unlock_page(page);
- page_cache_release(page);
-
- printk(KERN_ERR "ufs_change_blocknr: "
- "can not read page: ino %lu, index: %lu\n",
- mapping->host->i_ino, index);
-
- page = ERR_PTR(-EIO);
- }
- }
-out:
- return page;
-}
diff -urpN -X dontdiff linux-2.6.21-rc5-mm4/fs/ufs/util.h linux-2.6.21-rc5-mm4-test/fs/ufs/util.h
--- linux-2.6.21-rc5-mm4/fs/ufs/util.h 2007-04-05 17:13:29.000000000 -0700
+++ linux-2.6.21-rc5-mm4-test/fs/ufs/util.h 2007-04-06 12:46:36.000000000 -0700
@@ -251,16 +251,6 @@ extern void _ubh_ubhcpymem_(struct ufs_s
#define ubh_memcpyubh(ubh,mem,size) _ubh_memcpyubh_(uspi,ubh,mem,size)
extern void _ubh_memcpyubh_(struct ufs_sb_private_info *, struct ufs_buffer_head *, unsigned char *, unsigned);

-/* This functions works with cache pages*/
-extern struct page *ufs_get_locked_page(struct address_space *mapping,
- pgoff_t index);
-static inline void ufs_put_locked_page(struct page *page)
-{
- unlock_page(page);
- page_cache_release(page);
-}
-
-
/*
* macros and inline function to get important structures from ufs_sb_private_info
*/
diff -urpN -X dontdiff linux-2.6.21-rc5-mm4/fs/ufs/dir.c linux-2.6.21-rc5-mm4-test/fs/ufs/dir.c
--- linux-2.6.21-rc5-mm4/fs/ufs/dir.c 2007-04-06 12:27:03.000000000 -0700
+++ linux-2.6.21-rc5-mm4-test/fs/ufs/dir.c 2007-04-06 14:43:23.000000000 -0700
@@ -51,12 +51,6 @@ static int ufs_commit_chunk(struct page
return err;
}

-static inline void ufs_put_page(struct page *page)
-{
- kunmap(page);
- page_cache_release(page);
-}
-
static inline unsigned long ufs_dir_pages(struct inode *inode)
{
return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
@@ -71,7 +65,7 @@ ino_t ufs_inode_by_name(struct inode *di
de = ufs_find_entry(dir, dentry, &page);
if (de) {
res = fs32_to_cpu(dir->i_sb, de->d_ino);
- ufs_put_page(page);
+ put_kmapped_page(page);
}
return res;
}
@@ -91,13 +85,13 @@ void ufs_set_link(struct inode *dir, str
de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino);
ufs_set_de_type(dir->i_sb, de, inode->i_mode);
err = ufs_commit_chunk(page, from, to);
- ufs_put_page(page);
+ put_kmapped_page(page);
dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(dir);
}

-static void ufs_check_page(struct page *page)
+static int ufs_check_page(struct page *page)
{
struct inode *dir = page->mapping->host;
struct super_block *sb = dir->i_sb;
@@ -108,6 +102,14 @@ static void ufs_check_page(struct page *
struct ufs_dir_entry *p;
char *error;

+ if (likely(PageChecked(page))) {
+ if (likely(!PageError(page)))
+ return 0;
+
+ put_kmapped_page(page);
+ return -EIO;
+ }
+
if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
limit = dir->i_size & ~PAGE_CACHE_MASK;
if (limit & chunk_mask)
@@ -135,7 +137,7 @@ static void ufs_check_page(struct page *
goto Eend;
out:
SetPageChecked(page);
- return;
+ return 0;

/* Too bad, we had an error */

@@ -174,24 +176,8 @@ Eend:
fail:
SetPageChecked(page);
SetPageError(page);
-}
-
-static struct page *ufs_get_page(struct inode *dir, unsigned long n)
-{
- struct address_space *mapping = dir->i_mapping;
- struct page *page = read_mapping_page(mapping, n, NULL);
- if (!IS_ERR(page)) {
- kmap(page);
- if (!PageChecked(page))
- ufs_check_page(page);
- if (PageError(page))
- goto fail;
- }
- return page;
-
-fail:
- ufs_put_page(page);
- return ERR_PTR(-EIO);
+ put_kmapped_page(page);
+ return -EIO;
}

/*
@@ -218,10 +204,10 @@ ufs_next_entry(struct super_block *sb, s

struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p)
{
- struct page *page = ufs_get_page(dir, 0);
+ struct page *page = read_kmap_page(dir->i_mapping, 0);
struct ufs_dir_entry *de = NULL;

- if (!IS_ERR(page)) {
+ if (!IS_ERR(page) && !ufs_check_page(page)) {
de = ufs_next_entry(dir->i_sb,
(struct ufs_dir_entry *)page_address(page));
*p = page;
@@ -265,8 +251,8 @@ struct ufs_dir_entry *ufs_find_entry(str
n = start;
do {
char *kaddr;
- page = ufs_get_page(dir, n);
- if (!IS_ERR(page)) {
+ page = read_kmap_page(dir->i_mapping, n);
+ if (!IS_ERR(page) && !ufs_check_page(page)) {
kaddr = page_address(page);
de = (struct ufs_dir_entry *) kaddr;
kaddr += ufs_last_byte(dir, n) - reclen;
@@ -274,14 +260,14 @@ struct ufs_dir_entry *ufs_find_entry(str
if (de->d_reclen == 0) {
ufs_error(dir->i_sb, __FUNCTION__,
"zero-length directory entry");
- ufs_put_page(page);
+ put_kmapped_page(page);
goto out;
}
if (ufs_match(sb, namelen, name, de))
goto found;
de = ufs_next_entry(sb, de);
}
- ufs_put_page(page);
+ put_kmapped_page(page);
}
if (++n >= npages)
n = 0;
@@ -325,11 +311,13 @@ int ufs_add_link(struct dentry *dentry,
for (n = 0; n <= npages; n++) {
char *dir_end;

- page = ufs_get_page(dir, n);
+ page = __read_kmap_page(dir->i_mapping, n);
err = PTR_ERR(page);
if (IS_ERR(page))
goto out;
- lock_page(page);
+ err = ufs_check_page(page);
+ if (err)
+ goto out_unlock;
kaddr = page_address(page);
dir_end = kaddr + ufs_last_byte(dir, n);
de = (struct ufs_dir_entry *)kaddr;
@@ -360,8 +348,7 @@ int ufs_add_link(struct dentry *dentry,
goto got_it;
de = (struct ufs_dir_entry *) ((char *) de + rec_len);
}
- unlock_page(page);
- ufs_put_page(page);
+ put_locked_page(page);
}
BUG();
return -EINVAL;
@@ -391,13 +378,12 @@ got_it:

mark_inode_dirty(dir);
/* OFFSET_CACHE */
-out_put:
- ufs_put_page(page);
+ put_kmapped_page(page);
out:
return err;
out_unlock:
- unlock_page(page);
- goto out_put;
+ put_locked_page(page);
+ return err;
}

static inline unsigned
@@ -440,9 +426,9 @@ ufs_readdir(struct file *filp, void *dir
char *kaddr, *limit;
struct ufs_dir_entry *de;

- struct page *page = ufs_get_page(inode, n);
+ struct page *page = read_kmap_page(inode->i_mapping, n);

- if (IS_ERR(page)) {
+ if (IS_ERR(page) || ufs_check_page(page)) {
ufs_error(sb, __FUNCTION__,
"bad page in #%lu",
inode->i_ino);
@@ -464,7 +450,7 @@ ufs_readdir(struct file *filp, void *dir
if (de->d_reclen == 0) {
ufs_error(sb, __FUNCTION__,
"zero-length directory entry");
- ufs_put_page(page);
+ put_kmapped_page(page);
return -EIO;
}
if (de->d_ino) {
@@ -485,13 +471,13 @@ ufs_readdir(struct file *filp, void *dir
(n<<PAGE_CACHE_SHIFT) | offset,
fs32_to_cpu(sb, de->d_ino), d_type);
if (over) {
- ufs_put_page(page);
+ put_kmapped_page(page);
return 0;
}
}
filp->f_pos += fs16_to_cpu(sb, de->d_reclen);
}
- ufs_put_page(page);
+ put_kmapped_page(page);
}
return 0;
}
@@ -542,7 +528,7 @@ int ufs_delete_entry(struct inode *inode
inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
mark_inode_dirty(inode);
out:
- ufs_put_page(page);
+ put_kmapped_page(page);
UFSD("EXIT\n");
return err;
}
@@ -604,9 +590,9 @@ int ufs_empty_dir(struct inode * inode)
for (i = 0; i < npages; i++) {
char *kaddr;
struct ufs_dir_entry *de;
- page = ufs_get_page(inode, i);
+ page = read_kmap_page(inode->i_mapping, i);

- if (IS_ERR(page))
+ if (IS_ERR(page) || ufs_check_page(page))
continue;

kaddr = page_address(page);
@@ -636,12 +622,12 @@ int ufs_empty_dir(struct inode * inode)
}
de = ufs_next_entry(sb, de);
}
- ufs_put_page(page);
+ put_kmapped_page(page);
}
return 1;

not_empty:
- ufs_put_page(page);
+ put_kmapped_page(page);
return 0;
}