[PATCH] read_mapping_page for address space

Add read_mapping_page() which is used for callers that pass
mapping->a_ops->readpage as the filler for read_cache_page.  This removes
some duplication from filesystem code.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 9 insertions, 10 deletions

diff --git a/fs/hfsplus/bitmap.c b/fs/hfsplus/bitmap.c
index 9fb51632303c..d128a25b74d2 100644
--- a/fs/hfsplus/bitmap.c
+++ b/fs/hfsplus/bitmap.c
@@ -31,8 +31,7 @@ int hfsplus_block_allocate(struct super_block *sb, u32 size, u32 offset, u32 *ma
         dprint(DBG_BITMAP, "block_allocate: %u,%u,%u\n", size, offset, len);
         mutex_lock(&HFSPLUS_SB(sb).alloc_file->i_mutex);
         mapping = HFSPLUS_SB(sb).alloc_file->i_mapping;
-        page = read_cache_page(mapping, offset / PAGE_CACHE_BITS,
-                               (filler_t *)mapping->a_ops->readpage, NULL);
+        page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS, NULL);
         pptr = kmap(page);
         curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32;
         i = offset % 32;
@@ -72,8 +71,8 @@ int hfsplus_block_allocate(struct super_block *sb, u32 size, u32 offset, u32 *ma
                 offset += PAGE_CACHE_BITS;
                 if (offset >= size)
                         break;
-                page = read_cache_page(mapping, offset / PAGE_CACHE_BITS,
-                                       (filler_t *)mapping->a_ops->readpage, NULL);
+                page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS,
+                                         NULL);
                 curr = pptr = kmap(page);
                 if ((size ^ offset) / PAGE_CACHE_BITS)
                         end = pptr + PAGE_CACHE_BITS / 32;
@@ -119,8 +118,8 @@ found:
                 set_page_dirty(page);
                 kunmap(page);
                 offset += PAGE_CACHE_BITS;
-                page = read_cache_page(mapping, offset / PAGE_CACHE_BITS,
-                                       (filler_t *)mapping->a_ops->readpage, NULL);
+                page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS,
+                                         NULL);
                 pptr = kmap(page);
                 curr = pptr;
                 end = pptr + PAGE_CACHE_BITS / 32;
@@ -167,7 +166,7 @@ int hfsplus_block_free(struct super_block *sb, u32 offset, u32 count)
         mutex_lock(&HFSPLUS_SB(sb).alloc_file->i_mutex);
         mapping = HFSPLUS_SB(sb).alloc_file->i_mapping;
         pnr = offset / PAGE_CACHE_BITS;
-        page = read_cache_page(mapping, pnr, (filler_t *)mapping->a_ops->readpage, NULL);
+        page = read_mapping_page(mapping, pnr, NULL);
         pptr = kmap(page);
         curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32;
         end = pptr + PAGE_CACHE_BITS / 32;
@@ -199,7 +198,7 @@ int hfsplus_block_free(struct super_block *sb, u32 offset, u32 count)
                         break;
                 set_page_dirty(page);
                 kunmap(page);
-                page = read_cache_page(mapping, ++pnr, (filler_t *)mapping->a_ops->readpage, NULL);
+                page = read_mapping_page(mapping, ++pnr, NULL);
                 pptr = kmap(page);
                 curr = pptr;
                 end = pptr + PAGE_CACHE_BITS / 32;
diff --git a/fs/hfsplus/bnode.c b/fs/hfsplus/bnode.c
index 746abc9ecf70..77bf434da679 100644
--- a/fs/hfsplus/bnode.c
+++ b/fs/hfsplus/bnode.c
@@ -440,7 +440,7 @@ static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
         block = off >> PAGE_CACHE_SHIFT;
         node->page_offset = off & ~PAGE_CACHE_MASK;
         for (i = 0; i < tree->pages_per_bnode; block++, i++) {
-                page = read_cache_page(mapping, block, (filler_t *)mapping->a_ops->readpage, NULL);
+                page = read_mapping_page(mapping, block, NULL);
                 if (IS_ERR(page))
                         goto fail;
                 if (PageError(page)) {
diff --git a/fs/hfsplus/btree.c b/fs/hfsplus/btree.c
index effa8991999c..cfc852fdd1b5 100644
--- a/fs/hfsplus/btree.c
+++ b/fs/hfsplus/btree.c
@@ -38,7 +38,7 @@ struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id)
                 goto free_tree;
 
         mapping = tree->inode->i_mapping;
-        page = read_cache_page(mapping, 0, (filler_t *)mapping->a_ops->readpage, NULL);
+        page = read_mapping_page(mapping, 0, NULL);
         if (IS_ERR(page))
                 goto free_tree;