f2fs: introduce f2fs_map_bh to clean codes of check_extent_cache

This patch introduces f2fs_map_bh to clean codes of check_extent_cache.

v2:
 o cleanup f2fs_map_bh pointed out by Jaegeuk Kim.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 64f9049..bce0372 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -248,8 +248,23 @@ int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
        return err;
 }
 
+static void f2fs_map_bh(struct super_block *sb, pgoff_t pgofs,
+                       struct extent_info *ei, struct buffer_head *bh_result)
+{
+       unsigned int blkbits = sb->s_blocksize_bits;
+       size_t count;
+
+       set_buffer_new(bh_result);
+       map_bh(bh_result, sb, ei->blk + pgofs - ei->fofs);
+       count = ei->fofs + ei->len - pgofs;
+       if (count < (UINT_MAX >> blkbits))
+               bh_result->b_size = (count << blkbits);
+       else
+               bh_result->b_size = UINT_MAX;
+}
+
 static int check_extent_cache(struct inode *inode, pgoff_t pgofs,
-                                       struct buffer_head *bh_result)
+                                       struct extent_info *ei)
 {
        struct f2fs_inode_info *fi = F2FS_I(inode);
        pgoff_t start_fofs, end_fofs;
@@ -271,18 +286,7 @@ static int check_extent_cache(struct inode *inode, pgoff_t pgofs,
        start_blkaddr = fi->ext.blk;
 
        if (pgofs >= start_fofs && pgofs <= end_fofs) {
-               unsigned int blkbits = inode->i_sb->s_blocksize_bits;
-               size_t count;
-
-               set_buffer_new(bh_result);
-               map_bh(bh_result, inode->i_sb,
-                               start_blkaddr + pgofs - start_fofs);
-               count = end_fofs - pgofs + 1;
-               if (count < (UINT_MAX >> blkbits))
-                       bh_result->b_size = (count << blkbits);
-               else
-                       bh_result->b_size = UINT_MAX;
-
+               *ei = fi->ext;
                stat_inc_read_hit(inode->i_sb);
                read_unlock(&fi->ext_lock);
                return 1;
@@ -658,13 +662,16 @@ static int __get_data_block(struct inode *inode, sector_t iblock,
        int mode = create ? ALLOC_NODE : LOOKUP_NODE_RA;
        pgoff_t pgofs, end_offset;
        int err = 0, ofs = 1;
+       struct extent_info ei;
        bool allocated = false;
 
        /* Get the page offset from the block offset(iblock) */
        pgofs = (pgoff_t)(iblock >> (PAGE_CACHE_SHIFT - blkbits));
 
-       if (check_extent_cache(inode, pgofs, bh_result))
+       if (check_extent_cache(inode, pgofs, &ei)) {
+               f2fs_map_bh(inode->i_sb, pgofs, &ei, bh_result);
                goto out;
+       }
 
        if (create)
                f2fs_lock_op(F2FS_I_SB(inode));