9 files changed, 270 insertions, 177 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index f4e387452246..7dd9b50d5ebc 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -892,7 +892,16 @@ out:
         return err;
 }
 
-#define DIO_CREDITS (EXT4_RESERVE_TRANS_BLOCKS + 32)
+/* Maximum number of blocks we map for direct IO at once. */
+#define DIO_MAX_BLOCKS 4096
+/*
+ * Number of credits we need for writing DIO_MAX_BLOCKS:
+ * We need sb + group descriptor + bitmap + inode -> 4
+ * For B blocks with A block pointers per block we need:
+ * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect).
+ * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25.
+ */
+#define DIO_CREDITS 25
 
 int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
                         unsigned long max_blocks, struct buffer_head *bh,
@@ -939,49 +948,31 @@ static int ext4_get_block(struct inode *inode, sector_t iblock,
                         struct buffer_head *bh_result, int create)
 {
         handle_t *handle = ext4_journal_current_handle();
-        int ret = 0;
+        int ret = 0, started = 0;
         unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
 
-        if (!create)
-                goto get_block;         /* A read */
-
-        if (max_blocks == 1)
-                goto get_block;         /* A single block get */
-
-        if (handle->h_transaction->t_state == T_LOCKED) {
-                /*
-                 * Huge direct-io writes can hold off commits for long
-                 * periods of time.  Let this commit run.
-                 */
-                ext4_journal_stop(handle);
-                handle = ext4_journal_start(inode, DIO_CREDITS);
-                if (IS_ERR(handle))
+        if (create && !handle) {
+                /* Direct IO write... */
+                if (max_blocks > DIO_MAX_BLOCKS)
+                        max_blocks = DIO_MAX_BLOCKS;
+                handle = ext4_journal_start(inode, DIO_CREDITS +
+                              2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb));
+                if (IS_ERR(handle)) {
                         ret = PTR_ERR(handle);
-                goto get_block;
-        }
-
-        if (handle->h_buffer_credits <= EXT4_RESERVE_TRANS_BLOCKS) {
-                /*
-                 * Getting low on buffer credits...
-                 */
-                ret = ext4_journal_extend(handle, DIO_CREDITS);
-                if (ret > 0) {
-                        /*
-                         * Couldn't extend the transaction.  Start a new one.
-                         */
-                        ret = ext4_journal_restart(handle, DIO_CREDITS);
+                        goto out;
                 }
+                started = 1;
         }
 
-get_block:
-        if (ret == 0) {
-                ret = ext4_get_blocks_wrap(handle, inode, iblock,
+        ret = ext4_get_blocks_wrap(handle, inode, iblock,
                                         max_blocks, bh_result, create, 0);
-                if (ret > 0) {
-                        bh_result->b_size = (ret << inode->i_blkbits);
-                        ret = 0;
-                }
+        if (ret > 0) {
+                bh_result->b_size = (ret << inode->i_blkbits);
+                ret = 0;
         }
+        if (started)
+                ext4_journal_stop(handle);
+out:
         return ret;
 }
 
@@ -1671,7 +1662,8 @@ static int ext4_releasepage(struct page *page, gfp_t wait)
  * if the machine crashes during the write.
  *
  * If the O_DIRECT write is intantiating holes inside i_size and the machine
- * crashes then stale disk data _may_ be exposed inside the file.
+ * crashes then stale disk data _may_ be exposed inside the file. But current
+ * VFS code falls back into buffered path in that case so we are safe.
  */
 static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
                         const struct iovec *iov, loff_t offset,
@@ -1680,7 +1672,7 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
         struct file *file = iocb->ki_filp;
         struct inode *inode = file->f_mapping->host;
         struct ext4_inode_info *ei = EXT4_I(inode);
-        handle_t *handle = NULL;
+        handle_t *handle;
         ssize_t ret;
         int orphan = 0;
         size_t count = iov_length(iov, nr_segs);
@@ -1688,17 +1680,21 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
         if (rw == WRITE) {
                 loff_t final_size = offset + count;
 
-                handle = ext4_journal_start(inode, DIO_CREDITS);
-                if (IS_ERR(handle)) {
-                        ret = PTR_ERR(handle);
-                        goto out;
-                }
                 if (final_size > inode->i_size) {
+                        /* Credits for sb + inode write */
+                        handle = ext4_journal_start(inode, 2);
+                        if (IS_ERR(handle)) {
+                                ret = PTR_ERR(handle);
+                                goto out;
+                        }
                         ret = ext4_orphan_add(handle, inode);
-                        if (ret)
-                                goto out_stop;
+                        if (ret) {
+                                ext4_journal_stop(handle);
+                                goto out;
+                        }
                         orphan = 1;
                         ei->i_disksize = inode->i_size;
+                        ext4_journal_stop(handle);
                 }
         }
 
@@ -1706,18 +1702,21 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
                                  offset, nr_segs,
                                  ext4_get_block, NULL);
 
-        /*
-         * Reacquire the handle: ext4_get_block() can restart the transaction
-         */
-        handle = ext4_journal_current_handle();
-
-out_stop:
-        if (handle) {
+        if (orphan) {
                 int err;
 
-                if (orphan && inode->i_nlink)
+                /* Credits for sb + inode write */
+                handle = ext4_journal_start(inode, 2);
+                if (IS_ERR(handle)) {
+                        /* This is really bad luck. We've written the data
+                         * but cannot extend i_size. Bail out and pretend
+                         * the write failed... */
+                        ret = PTR_ERR(handle);
+                        goto out;
+                }
+                if (inode->i_nlink)
                         ext4_orphan_del(handle, inode);
-                if (orphan && ret > 0) {
+                if (ret > 0) {
                         loff_t end = offset + ret;
                         if (end > inode->i_size) {
                                 ei->i_disksize = end;
@@ -2758,13 +2757,7 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
                 ei->i_data[block] = raw_inode->i_block[block];
         INIT_LIST_HEAD(&ei->i_orphan);
 
-        if (inode->i_ino >= EXT4_FIRST_INO(inode->i_sb) + 1 &&
-            EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
-                /*
-                 * When mke2fs creates big inodes it does not zero out
-                 * the unused bytes above EXT4_GOOD_OLD_INODE_SIZE,
-                 * so ignore those first few inodes.
-                 */
+        if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
                 ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
                 if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
                     EXT4_INODE_SIZE(inode->i_sb)) {
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 76e5fedc0a0b..dd0fcfcb35ce 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -420,6 +420,7 @@
 #define MB_DEFAULT_GROUP_PREALLOC       512
 
 static struct kmem_cache *ext4_pspace_cachep;
+static struct kmem_cache *ext4_ac_cachep;
 
 #ifdef EXT4_BB_MAX_BLOCKS
 #undef EXT4_BB_MAX_BLOCKS
@@ -680,7 +681,6 @@ static void *mb_find_buddy(struct ext4_buddy *e4b, int order, int *max)
 {
         char *bb;
 
-        /* FIXME!! is this needed */
         BUG_ON(EXT4_MB_BITMAP(e4b) == EXT4_MB_BUDDY(e4b));
         BUG_ON(max == NULL);
 
@@ -964,7 +964,7 @@ static void ext4_mb_generate_buddy(struct super_block *sb,
         grp->bb_fragments = fragments;
 
         if (free != grp->bb_free) {
-                printk(KERN_DEBUG
+                ext4_error(sb, __FUNCTION__,
                         "EXT4-fs: group %lu: %u blocks in bitmap, %u in gd\n",
                         group, free, grp->bb_free);
                 grp->bb_free = free;
@@ -1821,13 +1821,24 @@ static void ext4_mb_complex_scan_group(struct ext4_allocation_context *ac,
                 i = ext4_find_next_zero_bit(bitmap,
                                                 EXT4_BLOCKS_PER_GROUP(sb), i);
                 if (i >= EXT4_BLOCKS_PER_GROUP(sb)) {
-                        BUG_ON(free != 0);
+                        /*
+                         * IF we corrupt the bitmap  we won't find any
+                         * free blocks even though group info says we
+                         * we have free blocks
+                         */
+                        ext4_error(sb, __FUNCTION__, "%d free blocks as per "
+                                        "group info. But bitmap says 0\n",
+                                        free);
                         break;
                 }
 
                 mb_find_extent(e4b, 0, i, ac->ac_g_ex.fe_len, &ex);
                 BUG_ON(ex.fe_len <= 0);
-                BUG_ON(free < ex.fe_len);
+                if (free < ex.fe_len) {
+                        ext4_error(sb, __FUNCTION__, "%d free blocks as per "
+                                        "group info. But got %d blocks\n",
+                                        free, ex.fe_len);
+                }
 
                 ext4_mb_measure_extent(ac, &ex, e4b);
 
@@ -2959,12 +2970,19 @@ int __init init_ext4_mballoc(void)
         if (ext4_pspace_cachep == NULL)
                 return -ENOMEM;
 
+        ext4_ac_cachep =
+                kmem_cache_create("ext4_alloc_context",
+                                     sizeof(struct ext4_allocation_context),
+                                     0, SLAB_RECLAIM_ACCOUNT, NULL);
+        if (ext4_ac_cachep == NULL) {
+                kmem_cache_destroy(ext4_pspace_cachep);
+                return -ENOMEM;
+        }
 #ifdef CONFIG_PROC_FS
         proc_root_ext4 = proc_mkdir(EXT4_ROOT, proc_root_fs);
         if (proc_root_ext4 == NULL)
                 printk(KERN_ERR "EXT4-fs: Unable to create %s\n", EXT4_ROOT);
 #endif
-
         return 0;
 }
 
@@ -2972,6 +2990,7 @@ void exit_ext4_mballoc(void)
 {
         /* XXX: synchronize_rcu(); */
         kmem_cache_destroy(ext4_pspace_cachep);
+        kmem_cache_destroy(ext4_ac_cachep);
 #ifdef CONFIG_PROC_FS
         remove_proc_entry(EXT4_ROOT, proc_root_fs);
 #endif
@@ -3069,7 +3088,7 @@ static int ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
 
 out_err:
         sb->s_dirt = 1;
-        put_bh(bitmap_bh);
+        brelse(bitmap_bh);
         return err;
 }
 
@@ -3354,13 +3373,10 @@ static void ext4_mb_use_group_pa(struct ext4_allocation_context *ac,
         ac->ac_pa = pa;
 
         /* we don't correct pa_pstart or pa_plen here to avoid
-         * possible race when tte group is being loaded concurrently
+         * possible race when the group is being loaded concurrently
          * instead we correct pa later, after blocks are marked
-         * in on-disk bitmap -- see ext4_mb_release_context() */
-        /*
-         * FIXME!! but the other CPUs can look at this particular
-         * pa and think that it have enought free blocks if we
-         * don't update pa_free here right ?
+         * in on-disk bitmap -- see ext4_mb_release_context()
+         * Other CPUs are prevented from allocating from this pa by lg_mutex
          */
         mb_debug("use %u/%u from group pa %p\n", pa->pa_lstart-len, len, pa);
 }
@@ -3699,7 +3715,7 @@ static int ext4_mb_release_inode_pa(struct ext4_buddy *e4b,
                                 struct buffer_head *bitmap_bh,
                                 struct ext4_prealloc_space *pa)
 {
-        struct ext4_allocation_context ac;
+        struct ext4_allocation_context *ac;
         struct super_block *sb = e4b->bd_sb;
         struct ext4_sb_info *sbi = EXT4_SB(sb);
         unsigned long end;
@@ -3715,9 +3731,13 @@ static int ext4_mb_release_inode_pa(struct ext4_buddy *e4b,
         BUG_ON(group != e4b->bd_group && pa->pa_len != 0);
         end = bit + pa->pa_len;
 
-        ac.ac_sb = sb;
-        ac.ac_inode = pa->pa_inode;
-        ac.ac_op = EXT4_MB_HISTORY_DISCARD;
+        ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
+
+        if (ac) {
+                ac->ac_sb = sb;
+                ac->ac_inode = pa->pa_inode;
+                ac->ac_op = EXT4_MB_HISTORY_DISCARD;
+        }
 
         while (bit < end) {
                 bit = ext4_find_next_zero_bit(bitmap_bh->b_data, end, bit);
@@ -3733,24 +3753,28 @@ static int ext4_mb_release_inode_pa(struct ext4_buddy *e4b,
                                 (unsigned) group);
                 free += next - bit;
 
-                ac.ac_b_ex.fe_group = group;
-                ac.ac_b_ex.fe_start = bit;
-                ac.ac_b_ex.fe_len = next - bit;
-                ac.ac_b_ex.fe_logical = 0;
-                ext4_mb_store_history(&ac);
+                if (ac) {
+                        ac->ac_b_ex.fe_group = group;
+                        ac->ac_b_ex.fe_start = bit;
+                        ac->ac_b_ex.fe_len = next - bit;
+                        ac->ac_b_ex.fe_logical = 0;
+                        ext4_mb_store_history(ac);
+                }
 
                 mb_free_blocks(pa->pa_inode, e4b, bit, next - bit);
                 bit = next + 1;
         }
         if (free != pa->pa_free) {
-                printk(KERN_ERR "pa %p: logic %lu, phys. %lu, len %lu\n",
+                printk(KERN_CRIT "pa %p: logic %lu, phys. %lu, len %lu\n",
                         pa, (unsigned long) pa->pa_lstart,
                         (unsigned long) pa->pa_pstart,
                         (unsigned long) pa->pa_len);
-                printk(KERN_ERR "free %u, pa_free %u\n", free, pa->pa_free);
+                ext4_error(sb, __FUNCTION__, "free %u, pa_free %u\n",
+                                                free, pa->pa_free);
         }
-        BUG_ON(free != pa->pa_free);
         atomic_add(free, &sbi->s_mb_discarded);
+        if (ac)
+                kmem_cache_free(ext4_ac_cachep, ac);
 
         return err;
 }
@@ -3758,12 +3782,15 @@ static int ext4_mb_release_inode_pa(struct ext4_buddy *e4b,
 static int ext4_mb_release_group_pa(struct ext4_buddy *e4b,
                                 struct ext4_prealloc_space *pa)
 {
-        struct ext4_allocation_context ac;
+        struct ext4_allocation_context *ac;
         struct super_block *sb = e4b->bd_sb;
         ext4_group_t group;
         ext4_grpblk_t bit;
 
-        ac.ac_op = EXT4_MB_HISTORY_DISCARD;
+        ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
+
+        if (ac)
+                ac->ac_op = EXT4_MB_HISTORY_DISCARD;
 
         BUG_ON(pa->pa_deleted == 0);
         ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, &bit);
@@ -3771,13 +3798,16 @@ static int ext4_mb_release_group_pa(struct ext4_buddy *e4b,
         mb_free_blocks(pa->pa_inode, e4b, bit, pa->pa_len);
         atomic_add(pa->pa_len, &EXT4_SB(sb)->s_mb_discarded);
 
-        ac.ac_sb = sb;
-        ac.ac_inode = NULL;
-        ac.ac_b_ex.fe_group = group;
-        ac.ac_b_ex.fe_start = bit;
-        ac.ac_b_ex.fe_len = pa->pa_len;
-        ac.ac_b_ex.fe_logical = 0;
-        ext4_mb_store_history(&ac);
+        if (ac) {
+                ac->ac_sb = sb;
+                ac->ac_inode = NULL;
+                ac->ac_b_ex.fe_group = group;
+                ac->ac_b_ex.fe_start = bit;
+                ac->ac_b_ex.fe_len = pa->pa_len;
+                ac->ac_b_ex.fe_logical = 0;
+                ext4_mb_store_history(ac);
+                kmem_cache_free(ext4_ac_cachep, ac);
+        }
 
         return 0;
 }
@@ -4231,7 +4261,7 @@ static int ext4_mb_discard_preallocations(struct super_block *sb, int needed)
 ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
                                  struct ext4_allocation_request *ar, int *errp)
 {
-        struct ext4_allocation_context ac;
+        struct ext4_allocation_context *ac = NULL;
         struct ext4_sb_info *sbi;
         struct super_block *sb;
         ext4_fsblk_t block = 0;
@@ -4257,53 +4287,60 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
         }
         inquota = ar->len;
 
+        ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
+        if (!ac) {
+                *errp = -ENOMEM;
+                return 0;
+        }
+
         ext4_mb_poll_new_transaction(sb, handle);
 
-        *errp = ext4_mb_initialize_context(&ac, ar);
+        *errp = ext4_mb_initialize_context(ac, ar);
         if (*errp) {
                 ar->len = 0;
                 goto out;
         }
 
-        ac.ac_op = EXT4_MB_HISTORY_PREALLOC;
-        if (!ext4_mb_use_preallocated(&ac)) {
+        ac->ac_op = EXT4_MB_HISTORY_PREALLOC;
+        if (!ext4_mb_use_preallocated(ac)) {
 
-                ac.ac_op = EXT4_MB_HISTORY_ALLOC;
-                ext4_mb_normalize_request(&ac, ar);
+                ac->ac_op = EXT4_MB_HISTORY_ALLOC;
+                ext4_mb_normalize_request(ac, ar);
 
 repeat:
                 /* allocate space in core */
-                ext4_mb_regular_allocator(&ac);
+                ext4_mb_regular_allocator(ac);
 
                 /* as we've just preallocated more space than
                  * user requested orinally, we store allocated
                  * space in a special descriptor */
-                if (ac.ac_status == AC_STATUS_FOUND &&
-                                ac.ac_o_ex.fe_len < ac.ac_b_ex.fe_len)
-                        ext4_mb_new_preallocation(&ac);
+                if (ac->ac_status == AC_STATUS_FOUND &&
+                                ac->ac_o_ex.fe_len < ac->ac_b_ex.fe_len)
+                        ext4_mb_new_preallocation(ac);
         }
 
-        if (likely(ac.ac_status == AC_STATUS_FOUND)) {
-                ext4_mb_mark_diskspace_used(&ac, handle);
+        if (likely(ac->ac_status == AC_STATUS_FOUND)) {
+                ext4_mb_mark_diskspace_used(ac, handle);
                 *errp = 0;
-                block = ext4_grp_offs_to_block(sb, &ac.ac_b_ex);
-                ar->len = ac.ac_b_ex.fe_len;
+                block = ext4_grp_offs_to_block(sb, &ac->ac_b_ex);
+                ar->len = ac->ac_b_ex.fe_len;
         } else {
-                freed  = ext4_mb_discard_preallocations(sb, ac.ac_o_ex.fe_len);
+                freed  = ext4_mb_discard_preallocations(sb, ac->ac_o_ex.fe_len);
                 if (freed)
                         goto repeat;
                 *errp = -ENOSPC;
-                ac.ac_b_ex.fe_len = 0;
+                ac->ac_b_ex.fe_len = 0;
                 ar->len = 0;
-                ext4_mb_show_ac(&ac);
+                ext4_mb_show_ac(ac);
         }
 
-        ext4_mb_release_context(&ac);
+        ext4_mb_release_context(ac);
 
 out:
         if (ar->len < inquota)
                 DQUOT_FREE_BLOCK(ar->inode, inquota - ar->len);
 
+        kmem_cache_free(ext4_ac_cachep, ac);
         return block;
 }
 static void ext4_mb_poll_new_transaction(struct super_block *sb,
@@ -4405,9 +4442,9 @@ void ext4_mb_free_blocks(handle_t *handle, struct inode *inode,
                         unsigned long block, unsigned long count,
                         int metadata, unsigned long *freed)
 {
-        struct buffer_head *bitmap_bh = 0;
+        struct buffer_head *bitmap_bh = NULL;
         struct super_block *sb = inode->i_sb;
-        struct ext4_allocation_context ac;
+        struct ext4_allocation_context *ac = NULL;
         struct ext4_group_desc *gdp;
         struct ext4_super_block *es;
         unsigned long overflow;
@@ -4436,9 +4473,12 @@ void ext4_mb_free_blocks(handle_t *handle, struct inode *inode,
 
         ext4_debug("freeing block %lu\n", block);
 
-        ac.ac_op = EXT4_MB_HISTORY_FREE;
-        ac.ac_inode = inode;
-        ac.ac_sb = sb;
+        ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
+        if (ac) {
+                ac->ac_op = EXT4_MB_HISTORY_FREE;
+                ac->ac_inode = inode;
+                ac->ac_sb = sb;
+        }
 
 do_more:
         overflow = 0;
@@ -4504,10 +4544,12 @@ do_more:
         BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
         err = ext4_journal_dirty_metadata(handle, bitmap_bh);
 
-        ac.ac_b_ex.fe_group = block_group;
-        ac.ac_b_ex.fe_start = bit;
-        ac.ac_b_ex.fe_len = count;
-        ext4_mb_store_history(&ac);
+        if (ac) {
+                ac->ac_b_ex.fe_group = block_group;
+                ac->ac_b_ex.fe_start = bit;
+                ac->ac_b_ex.fe_len = count;
+                ext4_mb_store_history(ac);
+        }
 
         if (metadata) {
                 /* blocks being freed are metadata. these blocks shouldn't
@@ -4548,5 +4590,7 @@ do_more:
 error_return:
         brelse(bitmap_bh);
         ext4_std_error(sb, err);
+        if (ac)
+                kmem_cache_free(ext4_ac_cachep, ac);
         return;
 }
diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
index 3ebc2332f52e..8c6c685b9d22 100644
--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -61,10 +61,9 @@ static int finish_range(handle_t *handle, struct inode *inode,
                 retval = ext4_journal_restart(handle, needed);
                 if (retval)
                         goto err_out;
-        }
-        if (needed) {
+        } else if (needed) {
                 retval = ext4_journal_extend(handle, needed);
-                if (retval != 0) {
+                if (retval) {
                         /*
                          * IF not able to extend the journal restart the journal
                          */
@@ -220,6 +219,26 @@ static int update_tind_extent_range(handle_t *handle, struct inode *inode,
 
 }
 
+static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
+{
+        int retval = 0, needed;
+
+        if (handle->h_buffer_credits > EXT4_RESERVE_TRANS_BLOCKS)
+                return 0;
+        /*
+         * We are freeing a blocks. During this we touch
+         * superblock, group descriptor and block bitmap.
+         * So allocate a credit of 3. We may update
+         * quota (user and group).
+         */
+        needed = 3 + 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
+
+        if (ext4_journal_extend(handle, needed) != 0)
+                retval = ext4_journal_restart(handle, needed);
+
+        return retval;
+}
+
 static int free_dind_blocks(handle_t *handle,
                                 struct inode *inode, __le32 i_data)
 {
@@ -234,11 +253,14 @@ static int free_dind_blocks(handle_t *handle,
 
         tmp_idata = (__le32 *)bh->b_data;
         for (i = 0; i < max_entries; i++) {
-                if (tmp_idata[i])
+                if (tmp_idata[i]) {
+                        extend_credit_for_blkdel(handle, inode);
                         ext4_free_blocks(handle, inode,
                                         le32_to_cpu(tmp_idata[i]), 1, 1);
+                }
         }
         put_bh(bh);
+        extend_credit_for_blkdel(handle, inode);
         ext4_free_blocks(handle, inode, le32_to_cpu(i_data), 1, 1);
         return 0;
 }
@@ -267,29 +289,32 @@ static int free_tind_blocks(handle_t *handle,
                 }
         }
         put_bh(bh);
+        extend_credit_for_blkdel(handle, inode);
         ext4_free_blocks(handle, inode, le32_to_cpu(i_data), 1, 1);
         return 0;
 }
 
-static int free_ind_block(handle_t *handle, struct inode *inode)
+static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
 {
         int retval;
-        struct ext4_inode_info *ei = EXT4_I(inode);
 
-        if (ei->i_data[EXT4_IND_BLOCK])
+        /* ei->i_data[EXT4_IND_BLOCK] */
+        if (i_data[0]) {
+                extend_credit_for_blkdel(handle, inode);
                 ext4_free_blocks(handle, inode,
-                                le32_to_cpu(ei->i_data[EXT4_IND_BLOCK]), 1, 1);
+                                le32_to_cpu(i_data[0]), 1, 1);
+        }
 
-        if (ei->i_data[EXT4_DIND_BLOCK]) {
-                retval = free_dind_blocks(handle, inode,
-                                                ei->i_data[EXT4_DIND_BLOCK]);
+        /* ei->i_data[EXT4_DIND_BLOCK] */
+        if (i_data[1]) {
+                retval = free_dind_blocks(handle, inode, i_data[1]);
                 if (retval)
                         return retval;
         }
 
-        if (ei->i_data[EXT4_TIND_BLOCK]) {
-                retval = free_tind_blocks(handle, inode,
-                                                ei->i_data[EXT4_TIND_BLOCK]);
+        /* ei->i_data[EXT4_TIND_BLOCK] */
+        if (i_data[2]) {
+                retval = free_tind_blocks(handle, inode, i_data[2]);
                 if (retval)
                         return retval;
         }
@@ -297,15 +322,13 @@ static int free_ind_block(handle_t *handle, struct inode *inode)
 }
 
 static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
-                                struct inode *tmp_inode, int retval)
+                                struct inode *tmp_inode)
 {
+        int retval;
+        __le32  i_data[3];
         struct ext4_inode_info *ei = EXT4_I(inode);
         struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
 
-        retval = free_ind_block(handle, inode);
-        if (retval)
-                goto err_out;
-
         /*
          * One credit accounted for writing the
          * i_data field of the original inode
@@ -317,6 +340,11 @@ static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
                         goto err_out;
         }
 
+        i_data[0] = ei->i_data[EXT4_IND_BLOCK];
+        i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
+        i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
+
+        down_write(&EXT4_I(inode)->i_data_sem);
         /*
          * We have the extent map build with the tmp inode.
          * Now copy the i_data across
@@ -336,8 +364,15 @@ static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
         spin_lock(&inode->i_lock);
         inode->i_blocks += tmp_inode->i_blocks;
         spin_unlock(&inode->i_lock);
+        up_write(&EXT4_I(inode)->i_data_sem);
 
+        /*
+         * We mark the inode dirty after, because we decrement the
+         * i_blocks when freeing the indirect meta-data blocks
+         */
+        retval = free_ind_block(handle, inode, i_data);
         ext4_mark_inode_dirty(handle, inode);
+
 err_out:
         return retval;
 }
@@ -365,6 +400,7 @@ static int free_ext_idx(handle_t *handle, struct inode *inode,
                 }
         }
         put_bh(bh);
+        extend_credit_for_blkdel(handle, inode);
         ext4_free_blocks(handle, inode, block, 1, 1);
         return retval;
 }
@@ -414,7 +450,12 @@ int ext4_ext_migrate(struct inode *inode, struct file *filp,
         if ((EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
                 return -EINVAL;
 
-        down_write(&EXT4_I(inode)->i_data_sem);
+        if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
+                /*
+                 * don't migrate fast symlink
+                 */
+                return retval;
+
         handle = ext4_journal_start(inode,
                                         EXT4_DATA_TRANS_BLOCKS(inode->i_sb) +
                                         EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
@@ -448,13 +489,6 @@ int ext4_ext_migrate(struct inode *inode, struct file *filp,
         ext4_orphan_add(handle, tmp_inode);
         ext4_journal_stop(handle);
 
-        ei = EXT4_I(inode);
-        i_data = ei->i_data;
-        memset(&lb, 0, sizeof(lb));
-
-        /* 32 bit block address 4 bytes */
-        max_entries = inode->i_sb->s_blocksize >> 2;
-
         /*
          * start with one credit accounted for
          * superblock modification.
@@ -463,7 +497,20 @@ int ext4_ext_migrate(struct inode *inode, struct file *filp,
          * trascation that created the inode. Later as and
          * when we add extents we extent the journal
          */
+        /*
+         * inode_mutex prevent write and truncate on the file. Read still goes
+         * through. We take i_data_sem in ext4_ext_swap_inode_data before we
+         * switch the inode format to prevent read.
+         */
+        mutex_lock(&(inode->i_mutex));
         handle = ext4_journal_start(inode, 1);
+
+        ei = EXT4_I(inode);
+        i_data = ei->i_data;
+        memset(&lb, 0, sizeof(lb));
+
+        /* 32 bit block address 4 bytes */
+        max_entries = inode->i_sb->s_blocksize >> 2;
         for (i = 0; i < EXT4_NDIR_BLOCKS; i++, blk_count++) {
                 if (i_data[i]) {
                         retval = update_extent_range(handle, tmp_inode,
@@ -501,19 +548,6 @@ int ext4_ext_migrate(struct inode *inode, struct file *filp,
          */
         retval = finish_range(handle, tmp_inode, &lb);
 err_out:
-        /*
-         * We are either freeing extent information or indirect
-         * blocks. During this we touch superblock, group descriptor
-         * and block bitmap. Later we mark the tmp_inode dirty
-         * via ext4_ext_tree_init. So allocate a credit of 4
-         * We may update quota (user and group).
-         *
-         * FIXME!! we may be touching bitmaps in different block groups.
-         */
-        if (ext4_journal_extend(handle,
-                        4 + 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb)) != 0)
-                ext4_journal_restart(handle,
-                                4 + 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb));
         if (retval)
                 /*
                  * Failure case delete the extent information with the
@@ -522,7 +556,11 @@ err_out:
                 free_ext_block(handle, tmp_inode);
         else
                 retval = ext4_ext_swap_inode_data(handle, inode,
-                                                        tmp_inode, retval);
+                                                        tmp_inode);
+
+        /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
+        if (ext4_journal_extend(handle, 1) != 0)
+                ext4_journal_restart(handle, 1);
 
         /*
          * Mark the tmp_inode as of size zero
@@ -550,8 +588,7 @@ err_out:
         tmp_inode->i_nlink = 0;
 
         ext4_journal_stop(handle);
-
-        up_write(&EXT4_I(inode)->i_data_sem);
+        mutex_unlock(&(inode->i_mutex));
 
         if (tmp_inode)
                 iput(tmp_inode);
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index d153bb5922fc..a9347fb43bcc 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2223,6 +2223,7 @@ retry:
                 inode->i_op = &ext4_fast_symlink_inode_operations;
                 memcpy((char*)&EXT4_I(inode)->i_data,symname,l);
                 inode->i_size = l-1;
+                EXT4_I(inode)->i_flags &= ~EXT4_EXTENTS_FL;
         }
         EXT4_I(inode)->i_disksize = inode->i_size;
         err = ext4_add_nondir(handle, dentry, inode);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 93beb865c20d..0072da75221f 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1919,6 +1919,17 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent)
                 printk(KERN_WARNING
                        "EXT4-fs warning: feature flags set on rev 0 fs, "
                        "running e2fsck is recommended\n");
+
+        /*
+         * Since ext4 is still considered development code, we require
+         * that the TEST_FILESYS flag in s->flags be set.
+         */
+        if (!(le32_to_cpu(es->s_flags) & EXT2_FLAGS_TEST_FILESYS)) {
+                printk(KERN_WARNING "EXT4-fs: %s: not marked "
+                       "OK to use with test code.\n", sb->s_id);
+                goto failed_mount;
+        }
+
         /*
          * Check feature flags regardless of the revision level, since we
          * previously didn't change the revision level when setting the flags,
diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c
index 8e08efcaede2..a38c7186c570 100644
--- a/fs/jbd/commit.c
+++ b/fs/jbd/commit.c
@@ -104,7 +104,8 @@ static int journal_write_commit_record(journal_t *journal,
 {
         struct journal_head *descriptor;
         struct buffer_head *bh;
-        int i, ret;
+        journal_header_t *header;
+        int ret;
         int barrier_done = 0;
 
         if (is_journal_aborted(journal))
@@ -116,13 +117,10 @@ static int journal_write_commit_record(journal_t *journal,
 
         bh = jh2bh(descriptor);
 
-        /* AKPM: buglet - add `i' to tmp! */
-        for (i = 0; i < bh->b_size; i += 512) {
-                journal_header_t *tmp = (journal_header_t*)bh->b_data;
-                tmp->h_magic = cpu_to_be32(JFS_MAGIC_NUMBER);
-                tmp->h_blocktype = cpu_to_be32(JFS_COMMIT_BLOCK);
-                tmp->h_sequence = cpu_to_be32(commit_transaction->t_tid);
-        }
+        header = (journal_header_t *)(bh->b_data);
+        header->h_magic = cpu_to_be32(JFS_MAGIC_NUMBER);
+        header->h_blocktype = cpu_to_be32(JFS_COMMIT_BLOCK);
+        header->h_sequence = cpu_to_be32(commit_transaction->t_tid);
 
         JBUFFER_TRACE(descriptor, "write commit block");
         set_buffer_dirty(bh);
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 4f302d279279..a8173081f831 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -136,18 +136,20 @@ static int journal_submit_commit_record(journal_t *journal,
 
         JBUFFER_TRACE(descriptor, "submit commit block");
         lock_buffer(bh);
-
+        get_bh(bh);
         set_buffer_dirty(bh);
         set_buffer_uptodate(bh);
         bh->b_end_io = journal_end_buffer_io_sync;
 
         if (journal->j_flags & JBD2_BARRIER &&
-                !JBD2_HAS_COMPAT_FEATURE(journal,
+                !JBD2_HAS_INCOMPAT_FEATURE(journal,
                                          JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) {
                 set_buffer_ordered(bh);
                 barrier_done = 1;
         }
         ret = submit_bh(WRITE, bh);
+        if (barrier_done)
+                clear_buffer_ordered(bh);
 
         /* is it possible for another commit to fail at roughly
          * the same time as this one?  If so, we don't want to
@@ -166,7 +168,6 @@ static int journal_submit_commit_record(journal_t *journal,
                 spin_unlock(&journal->j_state_lock);
 
                 /* And try again, without the barrier */
-                clear_buffer_ordered(bh);
                 set_buffer_uptodate(bh);
                 set_buffer_dirty(bh);
                 ret = submit_bh(WRITE, bh);
@@ -872,7 +873,8 @@ wait_for_iobuf:
                 if (err)
                         __jbd2_journal_abort_hard(journal);
         }
-        err = journal_wait_on_commit_record(cbh);
+        if (!err && !is_journal_aborted(journal))
+                err = journal_wait_on_commit_record(cbh);
 
         if (err)
                 jbd2_journal_abort(journal, err);
diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c
index d36356f7d222..146411387ada 100644
--- a/fs/jbd2/recovery.c
+++ b/fs/jbd2/recovery.c
@@ -641,7 +641,7 @@ static int do_one_pass(journal_t *journal,
                                 if (chksum_err) {
                                         info->end_transaction = next_commit_ID;
 
-                                        if (!JBD2_HAS_COMPAT_FEATURE(journal,
+                                        if (!JBD2_HAS_INCOMPAT_FEATURE(journal,
                                            JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)){
                                                 printk(KERN_ERR
                                                        "JBD: Transaction %u "
diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h
index c4f635a4dd25..250032548597 100644
--- a/include/linux/ext4_fs.h
+++ b/include/linux/ext4_fs.h
@@ -490,6 +490,13 @@ do {									       \
 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 
 /*
+ * Misc. filesystem flags
+ */
+#define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
+#define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
+#define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
+
+/*
  * Mount flags
  */
 #define EXT4_MOUNT_CHECK                0x00001 /* Do mount-time checks */