[PATCH 7/17] jffs2: convert jffs2_gc_fetch_page to read_cache_page

Nate Diller
2007-04-12T02:52:18Z

Replace jffs2_gc_fetch_page() and jffs2_gc_release_page() using the
read_cache_page() and put_kmapped_page() calls, and update the call site
accordingly. Explicit calls to kmap()/kunmap() make the code more clear.

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

---

diff -urpN -X dontdiff linux-2.6.21-rc5-mm4/fs/jffs2/fs.c linux-2.6.21-rc5-mm4-test/fs/jffs2/fs.c
--- linux-2.6.21-rc5-mm4/fs/jffs2/fs.c 2007-04-05 17:14:25.000000000 -0700
+++ linux-2.6.21-rc5-mm4-test/fs/jffs2/fs.c 2007-04-06 01:59:19.000000000 -0700
@@ -621,33 +621,6 @@ struct jffs2_inode_info *jffs2_gc_fetch_
return JFFS2_INODE_INFO(inode);
}

-unsigned char *jffs2_gc_fetch_page(struct jffs2_sb_info *c,
- struct jffs2_inode_info *f,
- unsigned long offset,
- unsigned long *priv)
-{
- struct inode *inode = OFNI_EDONI_2SFFJ(f);
- struct page *pg;
-
- pg = read_cache_page(inode->i_mapping, offset >> PAGE_CACHE_SHIFT,
- (void *)jffs2_do_readpage_unlock, inode);
- if (IS_ERR(pg))
- return (void *)pg;
-
- *priv = (unsigned long)pg;
- return kmap(pg);
-}
-
-void jffs2_gc_release_page(struct jffs2_sb_info *c,
- unsigned char *ptr,
- unsigned long *priv)
-{
- struct page *pg = (void *)*priv;
-
- kunmap(pg);
- page_cache_release(pg);
-}
-
static int jffs2_flash_setup(struct jffs2_sb_info *c) {
int ret = 0;

diff -urpN -X dontdiff linux-2.6.21-rc5-mm4/fs/jffs2/gc.c linux-2.6.21-rc5-mm4-test/fs/jffs2/gc.c
--- linux-2.6.21-rc5-mm4/fs/jffs2/gc.c 2007-04-05 17:13:10.000000000 -0700
+++ linux-2.6.21-rc5-mm4-test/fs/jffs2/gc.c 2007-04-06 01:59:19.000000000 -0700
@@ -1078,7 +1078,7 @@ static int jffs2_garbage_collect_dnode(s
uint32_t alloclen, offset, orig_end, orig_start;
int ret = 0;
unsigned char *comprbuf = NULL, *writebuf;
- unsigned long pg;
+ struct page *page;
unsigned char *pg_ptr;

memset(&ri, 0, sizeof(ri));
@@ -1219,12 +1219,16 @@ static int jffs2_garbage_collect_dnode(s
* page OK. We'll actually write it out again in commit_write, which is a little
* suboptimal, but at least we're correct.
*/
- pg_ptr = jffs2_gc_fetch_page(c, f, start, &pg);
+ page = read_cache_page(OFNI_EDONI_2SFFJ(f)->i_mapping,
+ start >> PAGE_CACHE_SHIFT,
+ (void *)jffs2_do_readpage_unlock,
+ OFNI_EDONI_2SFFJ(f));

- if (IS_ERR(pg_ptr)) {
+ if (IS_ERR(page)) {
printk(KERN_WARNING "read_cache_page() returned error: %ld\n", PTR_ERR(pg_ptr));
- return PTR_ERR(pg_ptr);
+ return PTR_ERR(page);
}
+ pg_ptr = kmap(page);

offset = start;
while(offset < orig_end) {
@@ -1287,6 +1291,7 @@ static int jffs2_garbage_collect_dnode(s
}
}

- jffs2_gc_release_page(c, pg_ptr, &pg);
+ kunmap(page);
+ page_cache_release(page);
return ret;
}