From: Namjae Jeon <namjae.j...@samsung.com>

Make the fibmap call the return the proper physical block number for any
offset request in the fallocated range.

Signed-off-by: Namjae Jeon <namjae.j...@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahra...@samsung.com>
---
 fs/fat/cache.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++------------
 fs/fat/fat.h   |  3 +++
 fs/fat/inode.c | 25 ++++++++++++++++++++++-
 3 files changed, 78 insertions(+), 14 deletions(-)

diff --git a/fs/fat/cache.c b/fs/fat/cache.c
index a132666..e26bc9a 100644
--- a/fs/fat/cache.c
+++ b/fs/fat/cache.c
@@ -303,6 +303,31 @@ static int fat_bmap_cluster(struct inode *inode, int 
cluster)
        return dclus;
 }
 
+static int fat_get_mapped_cluster(struct inode *inode, sector_t sector,
+                                 sector_t last_block,
+                                 unsigned long *mapped_blocks, sector_t *bmap)
+{
+       struct super_block *sb = inode->i_sb;
+       struct msdos_sb_info *sbi = MSDOS_SB(sb);
+       int cluster, offset;
+
+       cluster = sector >> (sbi->cluster_bits - sb->s_blocksize_bits);
+       offset  = sector & (sbi->sec_per_clus - 1);
+       cluster = fat_bmap_cluster(inode, cluster);
+
+       if (cluster < 0)
+               return cluster;
+
+       else if (cluster) {
+               *bmap = fat_clus_to_blknr(sbi, cluster) + offset;
+               *mapped_blocks = sbi->sec_per_clus - offset;
+               if (*mapped_blocks > last_block - sector)
+                       *mapped_blocks = last_block - sector;
+       }
+
+       return 0;
+}
+
 int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
             unsigned long *mapped_blocks, int create)
 {
@@ -311,7 +336,6 @@ int fat_bmap(struct inode *inode, sector_t sector, sector_t 
*phys,
        const unsigned long blocksize = sb->s_blocksize;
        const unsigned char blocksize_bits = sb->s_blocksize_bits;
        sector_t last_block;
-       int cluster, offset;
 
        *phys = 0;
        *mapped_blocks = 0;
@@ -338,16 +362,30 @@ int fat_bmap(struct inode *inode, sector_t sector, 
sector_t *phys,
                        return 0;
        }
 
-       cluster = sector >> (sbi->cluster_bits - sb->s_blocksize_bits);
-       offset  = sector & (sbi->sec_per_clus - 1);
-       cluster = fat_bmap_cluster(inode, cluster);
-       if (cluster < 0)
-               return cluster;
-       else if (cluster) {
-               *phys = fat_clus_to_blknr(sbi, cluster) + offset;
-               *mapped_blocks = sbi->sec_per_clus - offset;
-               if (*mapped_blocks > last_block - sector)
-                       *mapped_blocks = last_block - sector;
-       }
-       return 0;
+       return fat_get_mapped_cluster(inode, sector, last_block, mapped_blocks,
+                                     phys);
+}
+
+int fat_bmap2(struct inode *inode, sector_t sector,
+             unsigned long *mapped_blocks, struct buffer_head *bh_result,
+             int create, sector_t *bmap)
+{
+       struct super_block *sb = inode->i_sb;
+       sector_t last_block;
+       const unsigned long blocksize = sb->s_blocksize;
+       const unsigned char blocksize_bits = sb->s_blocksize_bits;
+
+       BUG_ON(create != 0);
+
+       *bmap = 0;
+       *mapped_blocks = 0;
+
+       last_block = (MSDOS_I(inode)->i_disksize + (blocksize - 1))
+               >> blocksize_bits;
+
+       if (sector >= last_block)
+               return 0;
+
+       return fat_get_mapped_cluster(inode, sector, last_block, mapped_blocks,
+                                     bmap);
 }
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index 7b5851f..7270bdb 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -290,6 +290,9 @@ extern int fat_get_cluster(struct inode *inode, int cluster,
                           int *fclus, int *dclus);
 extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
                    unsigned long *mapped_blocks, int create);
+extern int fat_bmap2(struct inode *inode, sector_t sector,
+                    unsigned long *mapped_blocks,
+                    struct buffer_head *bh_result, int create, sector_t *bmap);
 
 /* fat/dir.c */
 extern const struct file_operations fat_dir_operations;
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 9509d07..a4a0d5f 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -250,13 +250,36 @@ static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
        return ret;
 }
 
+static int fat_get_block_bmap(struct inode *inode, sector_t iblock,
+               struct buffer_head *bh_result, int create)
+{
+       struct super_block *sb = inode->i_sb;
+       unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
+       int err;
+       sector_t bmap;
+       unsigned long mapped_blocks;
+
+       err = fat_bmap2(inode, iblock, &mapped_blocks, bh_result, create,
+                       &bmap);
+       if (err)
+               return err;
+
+       if (bmap) {
+               map_bh(bh_result, sb, bmap);
+               max_blocks = min(mapped_blocks, max_blocks);
+       }
+
+       bh_result->b_size = max_blocks << sb->s_blocksize_bits;
+       return 0;
+}
+
 static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
 {
        sector_t blocknr;
 
        /* fat_get_cluster() assumes the requested blocknr isn't truncated. */
        down_read(&MSDOS_I(mapping->host)->truncate_lock);
-       blocknr = generic_block_bmap(mapping, block, fat_get_block);
+       blocknr = generic_block_bmap(mapping, block, fat_get_block_bmap);
        up_read(&MSDOS_I(mapping->host)->truncate_lock);
 
        return blocknr;
-- 
1.7.11-rc0


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to