ocfs2: fix wrong check in ocfs2_direct_IO_get_blocks

contig_blocks gotten from ocfs2_extent_map_get_blocks cannot be compared
with clusters_to_alloc. So convert it to clusters first.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Weiwei Wang <wangww631@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index be9905e..1a35c61 100644 (file)
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -523,7 +523,7 @@ static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock,
        unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
        unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
        unsigned long len = bh_result->b_size;
-       unsigned int clusters_to_alloc = 0;
+       unsigned int clusters_to_alloc = 0, contig_clusters = 0;
 
        cpos = ocfs2_blocks_to_clusters(inode->i_sb, iblock);
 
@@ -560,8 +560,10 @@ static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock,
                /* fill hole, allocate blocks can't be larger than the size
                 * of the hole */
                clusters_to_alloc = ocfs2_clusters_for_bytes(inode->i_sb, len);
-               if (clusters_to_alloc > contig_blocks)
-                       clusters_to_alloc = contig_blocks;
+               contig_clusters = ocfs2_clusters_for_blocks(inode->i_sb,
+                               contig_blocks);
+               if (clusters_to_alloc > contig_clusters)
+                       clusters_to_alloc = contig_clusters;
 
                /* allocate extent and insert them into the extent tree */
                ret = ocfs2_extend_allocation(inode, cpos,

diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 460c6c3..690ddc6 100644 (file)
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -717,6 +717,16 @@ static inline u64 ocfs2_clusters_to_blocks(struct super_block *sb,
        return (u64)clusters << c_to_b_bits;
 }
 
+static inline u32 ocfs2_clusters_for_blocks(struct super_block *sb,
+               u64 blocks)
+{
+       int b_to_c_bits = OCFS2_SB(sb)->s_clustersize_bits -
+                       sb->s_blocksize_bits;
+
+       blocks += (1 << b_to_c_bits) - 1;
+       return (u32)(blocks >> b_to_c_bits);
+}
+
 static inline u32 ocfs2_blocks_to_clusters(struct super_block *sb,
                                           u64 blocks)
 {