[PATCH] fat: support ->direct_IO()

[linux-2.6-omap-h63xx.git] / fs / fat / cache.c

diff --git a/fs/fat/cache.c b/fs/fat/cache.c
index 77c24fcf712aefdc626781eee7a5bcbb10c62493..1acc941245fb4a4c751c972684202b19d0f2208a 100644 (file)
--- a/fs/fat/cache.c
+++ b/fs/fat/cache.c
@@ -295,7 +295,8 @@ static int fat_bmap_cluster(struct inode *inode, int cluster)
        return dclus;
 }
 
-int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys)
+int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
+            unsigned long *mapped_blocks)
 {
        struct super_block *sb = inode->i_sb;
        struct msdos_sb_info *sbi = MSDOS_SB(sb);
@@ -303,9 +304,12 @@ int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys)
        int cluster, offset;
 
        *phys = 0;
+       *mapped_blocks = 0;
        if ((sbi->fat_bits != 32) && (inode->i_ino == MSDOS_ROOT_INO)) {
-               if (sector < (sbi->dir_entries >> sbi->dir_per_block_bits))
+               if (sector < (sbi->dir_entries >> sbi->dir_per_block_bits)) {
                        *phys = sector + sbi->dir_start;
+                       *mapped_blocks = 1;
+               }
                return 0;
        }
        last_block = (MSDOS_I(inode)->mmu_private + (sb->s_blocksize - 1))
@@ -318,7 +322,11 @@ int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys)
        cluster = fat_bmap_cluster(inode, cluster);
        if (cluster < 0)
                return cluster;
-       else if (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;
 }