4 files changed, 48 insertions, 37 deletions

diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index aca191bd5f8f..6eaa28c98ad1 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -98,8 +98,8 @@ next:
 
         *bh = sb_bread(sb, phys);
         if (*bh == NULL) {
-                fat_msg(sb, KERN_ERR, "Directory bread(block %llu) failed",
-                       (llu)phys);
+                fat_msg_ratelimit(sb, KERN_ERR,
+                        "Directory bread(block %llu) failed", (llu)phys);
                 /* skip this block */
                 *pos = (iblock + 1) << sb->s_blocksize_bits;
                 goto next;
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index 66994f316e18..fc35c5c69136 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -82,6 +82,7 @@ struct msdos_sb_info {
         int fatent_shift;
         struct fatent_operations *fatent_ops;
         struct inode *fat_inode;
+        struct inode *fsinfo_inode;
 
         struct ratelimit_state ratelimit;
 
@@ -334,6 +335,11 @@ void __fat_fs_error(struct super_block *sb, int report, const char *fmt, ...);
         __fat_fs_error(sb, __ratelimit(&MSDOS_SB(sb)->ratelimit), fmt , ## args)
 __printf(3, 4) __cold
 void fat_msg(struct super_block *sb, const char *level, const char *fmt, ...);
+#define fat_msg_ratelimit(sb, level, fmt, args...)      \
+        do {    \
+                        if (__ratelimit(&MSDOS_SB(sb)->ratelimit))      \
+                                fat_msg(sb, level, fmt, ## args);       \
+         } while (0)
 extern int fat_clusters_flush(struct super_block *sb);
 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
 extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
diff --git a/fs/fat/fatent.c b/fs/fat/fatent.c
index 2e81ac0df7e2..31f08ab62c56 100644
--- a/fs/fat/fatent.c
+++ b/fs/fat/fatent.c
@@ -308,6 +308,16 @@ void fat_ent_access_init(struct super_block *sb)
         }
 }
 
+static void mark_fsinfo_dirty(struct super_block *sb)
+{
+        struct msdos_sb_info *sbi = MSDOS_SB(sb);
+
+        if (sb->s_flags & MS_RDONLY || sbi->fat_bits != 32)
+                return;
+
+        __mark_inode_dirty(sbi->fsinfo_inode, I_DIRTY_SYNC);
+}
+
 static inline int fat_ent_update_ptr(struct super_block *sb,
                                      struct fat_entry *fatent,
                                      int offset, sector_t blocknr)
@@ -498,7 +508,6 @@ int fat_alloc_clusters(struct inode *inode, int *cluster, int nr_cluster)
                                 sbi->prev_free = entry;
                                 if (sbi->free_clusters != -1)
                                         sbi->free_clusters--;
-                                sb->s_dirt = 1;
 
                                 cluster[idx_clus] = entry;
                                 idx_clus++;
@@ -520,11 +529,11 @@ int fat_alloc_clusters(struct inode *inode, int *cluster, int nr_cluster)
         /* Couldn't allocate the free entries */
         sbi->free_clusters = 0;
         sbi->free_clus_valid = 1;
-        sb->s_dirt = 1;
         err = -ENOSPC;
 
 out:
         unlock_fat(sbi);
+        mark_fsinfo_dirty(sb);
         fatent_brelse(&fatent);
         if (!err) {
                 if (inode_needs_sync(inode))
@@ -549,7 +558,7 @@ int fat_free_clusters(struct inode *inode, int cluster)
         struct fat_entry fatent;
         struct buffer_head *bhs[MAX_BUF_PER_PAGE];
         int i, err, nr_bhs;
-        int first_cl = cluster;
+        int first_cl = cluster, dirty_fsinfo = 0;
 
         nr_bhs = 0;
         fatent_init(&fatent);
@@ -587,7 +596,7 @@ int fat_free_clusters(struct inode *inode, int cluster)
                 ops->ent_put(&fatent, FAT_ENT_FREE);
                 if (sbi->free_clusters != -1) {
                         sbi->free_clusters++;
-                        sb->s_dirt = 1;
+                        dirty_fsinfo = 1;
                 }
 
                 if (nr_bhs + fatent.nr_bhs > MAX_BUF_PER_PAGE) {
@@ -617,6 +626,8 @@ error:
         for (i = 0; i < nr_bhs; i++)
                 brelse(bhs[i]);
         unlock_fat(sbi);
+        if (dirty_fsinfo)
+                mark_fsinfo_dirty(sb);
 
         return err;
 }
@@ -677,7 +688,7 @@ int fat_count_free_clusters(struct super_block *sb)
         }
         sbi->free_clusters = free;
         sbi->free_clus_valid = 1;
-        sb->s_dirt = 1;
+        mark_fsinfo_dirty(sb);
         fatent_brelse(&fatent);
 out:
         unlock_fat(sbi);
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 7edfaadc0787..a3d81ebf6d86 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -459,37 +459,11 @@ static void fat_evict_inode(struct inode *inode)
         fat_detach(inode);
 }
 
-static void fat_write_super(struct super_block *sb)
-{
-        lock_super(sb);
-        sb->s_dirt = 0;
-
-        if (!(sb->s_flags & MS_RDONLY))
-                fat_clusters_flush(sb);
-        unlock_super(sb);
-}
-
-static int fat_sync_fs(struct super_block *sb, int wait)
-{
-        int err = 0;
-
-        if (sb->s_dirt) {
-                lock_super(sb);
-                sb->s_dirt = 0;
-                err = fat_clusters_flush(sb);
-                unlock_super(sb);
-        }
-
-        return err;
-}
-
 static void fat_put_super(struct super_block *sb)
 {
         struct msdos_sb_info *sbi = MSDOS_SB(sb);
 
-        if (sb->s_dirt)
-                fat_write_super(sb);
-
+        iput(sbi->fsinfo_inode);
         iput(sbi->fat_inode);
 
         unload_nls(sbi->nls_disk);
@@ -661,7 +635,18 @@ retry:
 
 static int fat_write_inode(struct inode *inode, struct writeback_control *wbc)
 {
-        return __fat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
+        int err;
+
+        if (inode->i_ino == MSDOS_FSINFO_INO) {
+                struct super_block *sb = inode->i_sb;
+
+                lock_super(sb);
+                err = fat_clusters_flush(sb);
+                unlock_super(sb);
+        } else
+                err = __fat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
+
+        return err;
 }
 
 int fat_sync_inode(struct inode *inode)
@@ -678,8 +663,6 @@ static const struct super_operations fat_sops = {
         .write_inode    = fat_write_inode,
         .evict_inode    = fat_evict_inode,
         .put_super      = fat_put_super,
-        .write_super    = fat_write_super,
-        .sync_fs        = fat_sync_fs,
         .statfs         = fat_statfs,
         .remount_fs     = fat_remount,
 
@@ -1243,6 +1226,7 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,
                    void (*setup)(struct super_block *))
 {
         struct inode *root_inode = NULL, *fat_inode = NULL;
+        struct inode *fsinfo_inode = NULL;
         struct buffer_head *bh;
         struct fat_boot_sector *b;
         struct msdos_sb_info *sbi;
@@ -1489,6 +1473,14 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,
                 goto out_fail;
         MSDOS_I(fat_inode)->i_pos = 0;
         sbi->fat_inode = fat_inode;
+
+        fsinfo_inode = new_inode(sb);
+        if (!fsinfo_inode)
+                goto out_fail;
+        fsinfo_inode->i_ino = MSDOS_FSINFO_INO;
+        sbi->fsinfo_inode = fsinfo_inode;
+        insert_inode_hash(fsinfo_inode);
+
         root_inode = new_inode(sb);
         if (!root_inode)
                 goto out_fail;
@@ -1515,6 +1507,8 @@ out_invalid:
                 fat_msg(sb, KERN_INFO, "Can't find a valid FAT filesystem");
 
 out_fail:
+        if (fsinfo_inode)
+                iput(fsinfo_inode);
         if (fat_inode)
                 iput(fat_inode);
         unload_nls(sbi->nls_io);