Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 bugfixes from Ted Ts'o:
 "Bug fixes (all for stable kernels) for ext4:

   - address corner cases for indirect blocks->extent migration

   - fix reserved block accounting invalidate_page when
     page_size != block_size (i.e., ppc or 1k block size file systems)

   - fix deadlocks when a memcg is under heavy memory pressure

   - fix fencepost error in lazytime optimization"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: replace open coded nofail allocation in ext4_free_blocks()
  ext4: correctly migrate a file with a hole at the beginning
  ext4: be more strict when migrating to non-extent based file
  ext4: fix reservation release on invalidatepage for delalloc fs
  ext4: avoid deadlocks in the writeback path by using sb_getblk_gfp
  bufferhead: Add _gfp version for sb_getblk()
  ext4: fix fencepost error in lazytime optimization

5 files changed, 47 insertions, 21 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index aadb72828834..2553aa8b608d 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -504,7 +504,7 @@ __read_extent_tree_block(const char *function, unsigned int line,
         struct buffer_head              *bh;
         int                             err;
 
-        bh = sb_getblk(inode->i_sb, pblk);
+        bh = sb_getblk_gfp(inode->i_sb, pblk, __GFP_MOVABLE | GFP_NOFS);
         if (unlikely(!bh))
                 return ERR_PTR(-ENOMEM);
 
@@ -1089,7 +1089,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
                 err = -EIO;
                 goto cleanup;
         }
-        bh = sb_getblk(inode->i_sb, newblock);
+        bh = sb_getblk_gfp(inode->i_sb, newblock, __GFP_MOVABLE | GFP_NOFS);
         if (unlikely(!bh)) {
                 err = -ENOMEM;
                 goto cleanup;
@@ -1283,7 +1283,7 @@ static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
         if (newblock == 0)
                 return err;
 
-        bh = sb_getblk(inode->i_sb, newblock);
+        bh = sb_getblk_gfp(inode->i_sb, newblock, __GFP_MOVABLE | GFP_NOFS);
         if (unlikely(!bh))
                 return -ENOMEM;
         lock_buffer(bh);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 41f8e55afcd1..cecf9aa10811 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1323,7 +1323,7 @@ static void ext4_da_page_release_reservation(struct page *page,
                                              unsigned int offset,
                                              unsigned int length)
 {
-        int to_release = 0;
+        int to_release = 0, contiguous_blks = 0;
         struct buffer_head *head, *bh;
         unsigned int curr_off = 0;
         struct inode *inode = page->mapping->host;
@@ -1344,14 +1344,23 @@ static void ext4_da_page_release_reservation(struct page *page,
 
                 if ((offset <= curr_off) && (buffer_delay(bh))) {
                         to_release++;
+                        contiguous_blks++;
                         clear_buffer_delay(bh);
+                } else if (contiguous_blks) {
+                        lblk = page->index <<
+                               (PAGE_CACHE_SHIFT - inode->i_blkbits);
+                        lblk += (curr_off >> inode->i_blkbits) -
+                                contiguous_blks;
+                        ext4_es_remove_extent(inode, lblk, contiguous_blks);
+                        contiguous_blks = 0;
                 }
                 curr_off = next_off;
         } while ((bh = bh->b_this_page) != head);
 
-        if (to_release) {
+        if (contiguous_blks) {
                 lblk = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
-                ext4_es_remove_extent(inode, lblk, to_release);
+                lblk += (curr_off >> inode->i_blkbits) - contiguous_blks;
+                ext4_es_remove_extent(inode, lblk, contiguous_blks);
         }
 
         /* If we have released all the blocks belonging to a cluster, then we
@@ -4344,7 +4353,12 @@ static void ext4_update_other_inodes_time(struct super_block *sb,
         int inode_size = EXT4_INODE_SIZE(sb);
 
         oi.orig_ino = orig_ino;
-        ino = (orig_ino & ~(inodes_per_block - 1)) + 1;
+        /*
+         * Calculate the first inode in the inode table block.  Inode
+         * numbers are one-based.  That is, the first inode in a block
+         * (assuming 4k blocks and 256 byte inodes) is (n*16 + 1).
+         */
+        ino = ((orig_ino - 1) & ~(inodes_per_block - 1)) + 1;
         for (i = 0; i < inodes_per_block; i++, ino++, buf += inode_size) {
                 if (ino == orig_ino)
                         continue;
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index f6aedf88da43..34b610ea5030 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4816,18 +4816,12 @@ do_more:
                 /*
                  * blocks being freed are metadata. these blocks shouldn't
                  * be used until this transaction is committed
+                 *
+                 * We use __GFP_NOFAIL because ext4_free_blocks() is not allowed
+                 * to fail.
                  */
-        retry:
-                new_entry = kmem_cache_alloc(ext4_free_data_cachep, GFP_NOFS);
-                if (!new_entry) {
-                        /*
-                         * We use a retry loop because
-                         * ext4_free_blocks() is not allowed to fail.
-                         */
-                        cond_resched();
-                        congestion_wait(BLK_RW_ASYNC, HZ/50);
-                        goto retry;
-                }
+                new_entry = kmem_cache_alloc(ext4_free_data_cachep,
+                                GFP_NOFS|__GFP_NOFAIL);
                 new_entry->efd_start_cluster = bit;
                 new_entry->efd_group = block_group;
                 new_entry->efd_count = count_clusters;
diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
index b52374e42102..6163ad21cb0e 100644
--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -620,6 +620,7 @@ int ext4_ind_migrate(struct inode *inode)
         struct ext4_inode_info          *ei = EXT4_I(inode);
         struct ext4_extent              *ex;
         unsigned int                    i, len;
+        ext4_lblk_t                     start, end;
         ext4_fsblk_t                    blk;
         handle_t                        *handle;
         int                             ret;
@@ -633,6 +634,14 @@ int ext4_ind_migrate(struct inode *inode)
                                        EXT4_FEATURE_RO_COMPAT_BIGALLOC))
                 return -EOPNOTSUPP;
 
+        /*
+         * In order to get correct extent info, force all delayed allocation
+         * blocks to be allocated, otherwise delayed allocation blocks may not
+         * be reflected and bypass the checks on extent header.
+         */
+        if (test_opt(inode->i_sb, DELALLOC))
+                ext4_alloc_da_blocks(inode);
+
         handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
         if (IS_ERR(handle))
                 return PTR_ERR(handle);
@@ -650,11 +659,13 @@ int ext4_ind_migrate(struct inode *inode)
                 goto errout;
         }
         if (eh->eh_entries == 0)
-                blk = len = 0;
+                blk = len = start = end = 0;
         else {
                 len = le16_to_cpu(ex->ee_len);
                 blk = ext4_ext_pblock(ex);
-                if (len > EXT4_NDIR_BLOCKS) {
+                start = le32_to_cpu(ex->ee_block);
+                end = start + len - 1;
+                if (end >= EXT4_NDIR_BLOCKS) {
                         ret = -EOPNOTSUPP;
                         goto errout;
                 }
@@ -662,7 +673,7 @@ int ext4_ind_migrate(struct inode *inode)
 
         ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
         memset(ei->i_data, 0, sizeof(ei->i_data));
-        for (i=0; i < len; i++)
+        for (i = start; i <= end; i++)
                 ei->i_data[i] = cpu_to_le32(blk++);
         ext4_mark_inode_dirty(handle, inode);
 errout:
diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index 73b45225a7ca..e6797ded700e 100644
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h
@@ -317,6 +317,13 @@ sb_getblk(struct super_block *sb, sector_t block)
         return __getblk_gfp(sb->s_bdev, block, sb->s_blocksize, __GFP_MOVABLE);
 }
 
+
+static inline struct buffer_head *
+sb_getblk_gfp(struct super_block *sb, sector_t block, gfp_t gfp)
+{
+        return __getblk_gfp(sb->s_bdev, block, sb->s_blocksize, gfp);
+}
+
 static inline struct buffer_head *
 sb_find_get_block(struct super_block *sb, sector_t block)
 {