fat: permit to return phy block number by fibmap in fallocated region

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.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/fat/cache.c b/fs/fat/cache.c
index c56bd7e4af925f2417ef21312ee9aec0bdae5313..77778227911a6d1b45a554e5e684bf6fc6c7c466 100644 (file)
--- a/fs/fat/cache.c
+++ b/fs/fat/cache.c
@@ -312,6 +312,7 @@ int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
        const unsigned char blocksize_bits = sb->s_blocksize_bits;
        sector_t last_block;
        int cluster, offset;
+       loff_t i_size = i_size_read(inode);
 
        *phys = 0;
        *mapped_blocks = 0;
@@ -323,10 +324,20 @@ int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
                return 0;
        }
 
-       last_block = (i_size_read(inode) + (blocksize - 1)) >> blocksize_bits;
+       last_block = (i_size + (blocksize - 1)) >> blocksize_bits;
        if (sector >= last_block) {
-               if (!create)
+               if (!create) {
+                       /*
+                        * to map cluster in case of read request
+                        * for a block in fallocated region
+                        */
+                       if (MSDOS_I(inode)->i_disksize >
+                           round_up(i_size, sb->s_blocksize)) {
+                               goto out_map_cluster;
+                       }
+
                        return 0;
+               }
 
                /*
                 * Both ->mmu_private and ->i_disksize can access
@@ -339,6 +350,7 @@ int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
                        return 0;
        }
 
+out_map_cluster:
        cluster = sector >> (sbi->cluster_bits - sb->s_blocksize_bits);
        offset  = sector & (sbi->sec_per_clus - 1);
        cluster = fat_bmap_cluster(inode, cluster);

diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index ffa2eccc62a2a522bed1ede8531b75fa01487f12..4b796d5d735f5a65ed9e75b3e676728a318b0da6 100644 (file)
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -245,9 +245,9 @@ 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);
+       mutex_lock(&mapping->host->i_mutex);
        blocknr = generic_block_bmap(mapping, block, fat_get_block);
-       up_read(&MSDOS_I(mapping->host)->truncate_lock);
+       mutex_unlock(&mapping->host->i_mutex);
 
        return blocknr;
 }