Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 bugfixes from Ted Ts'o:
 "Fixes for 3.11-rc2, sent at 5pm, in the professoinal style.  :-)"

I'm not sure I like this new level of "professionalism".
9-5, people, 9-5.

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: call ext4_es_lru_add() after handling cache miss
  ext4: yield during large unlinks
  ext4: make the extent_status code more robust against ENOMEM failures
  ext4: simplify calculation of blocks to free on error
  ext4: fix error handling in ext4_ext_truncate()

3 files changed, 60 insertions, 21 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 7097b0f680e6..a61873808f76 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -2835,6 +2835,9 @@ again:
                                 err = -EIO;
                                 break;
                         }
+                        /* Yield here to deal with large extent trees.
+                         * Should be a no-op if we did IO above. */
+                        cond_resched();
                         if (WARN_ON(i + 1 > depth)) {
                                 err = -EIO;
                                 break;
@@ -4261,8 +4264,8 @@ got_allocated_blocks:
                 /* not a good idea to call discard here directly,
                  * but otherwise we'd need to call it every free() */
                 ext4_discard_preallocations(inode);
-                ext4_free_blocks(handle, inode, NULL, ext4_ext_pblock(&newex),
-                                 ext4_ext_get_actual_len(&newex), fb_flags);
+                ext4_free_blocks(handle, inode, NULL, newblock,
+                                 EXT4_C2B(sbi, allocated_clusters), fb_flags);
                 goto out2;
         }
 
@@ -4382,8 +4385,9 @@ out2:
         }
 
 out3:
-        trace_ext4_ext_map_blocks_exit(inode, flags, map, err ? err : allocated);
-
+        trace_ext4_ext_map_blocks_exit(inode, flags, map,
+                                       err ? err : allocated);
+        ext4_es_lru_add(inode);
         return err ? err : allocated;
 }
 
@@ -4405,9 +4409,20 @@ void ext4_ext_truncate(handle_t *handle, struct inode *inode)
 
         last_block = (inode->i_size + sb->s_blocksize - 1)
                         >> EXT4_BLOCK_SIZE_BITS(sb);
+retry:
         err = ext4_es_remove_extent(inode, last_block,
                                     EXT_MAX_BLOCKS - last_block);
+        if (err == ENOMEM) {
+                cond_resched();
+                congestion_wait(BLK_RW_ASYNC, HZ/50);
+                goto retry;
+        }
+        if (err) {
+                ext4_std_error(inode->i_sb, err);
+                return;
+        }
         err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
+        ext4_std_error(inode->i_sb, err);
 }
 
 static void ext4_falloc_update_inode(struct inode *inode,
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index 4b8df7fbb10a..91cb110da1b4 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -148,6 +148,8 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
                               ext4_lblk_t end);
 static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei,
                                        int nr_to_scan);
+static int __ext4_es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
+                            struct ext4_inode_info *locked_ei);
 
 int __init ext4_init_es(void)
 {
@@ -665,7 +667,13 @@ int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
         err = __es_remove_extent(inode, lblk, end);
         if (err != 0)
                 goto error;
+retry:
         err = __es_insert_extent(inode, &newes);
+        if (err == -ENOMEM && __ext4_es_shrink(EXT4_SB(inode->i_sb), 1,
+                                               EXT4_I(inode)))
+                goto retry;
+        if (err == -ENOMEM && !ext4_es_is_delayed(&newes))
+                err = 0;
 
 error:
         write_unlock(&EXT4_I(inode)->i_es_lock);
@@ -744,8 +752,10 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
         struct extent_status orig_es;
         ext4_lblk_t len1, len2;
         ext4_fsblk_t block;
-        int err = 0;
+        int err;
 
+retry:
+        err = 0;
         es = __es_tree_search(&tree->root, lblk);
         if (!es)
                 goto out;
@@ -780,6 +790,10 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
                         if (err) {
                                 es->es_lblk = orig_es.es_lblk;
                                 es->es_len = orig_es.es_len;
+                                if ((err == -ENOMEM) &&
+                                    __ext4_es_shrink(EXT4_SB(inode->i_sb), 1,
+                                                     EXT4_I(inode)))
+                                        goto retry;
                                 goto out;
                         }
                 } else {
@@ -889,22 +903,14 @@ static int ext4_inode_touch_time_cmp(void *priv, struct list_head *a,
                 return -1;
 }
 
-static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
+static int __ext4_es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
+                            struct ext4_inode_info *locked_ei)
 {
-        struct ext4_sb_info *sbi = container_of(shrink,
-                                        struct ext4_sb_info, s_es_shrinker);
         struct ext4_inode_info *ei;
         struct list_head *cur, *tmp;
         LIST_HEAD(skiped);
-        int nr_to_scan = sc->nr_to_scan;
         int ret, nr_shrunk = 0;
 
-        ret = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
-        trace_ext4_es_shrink_enter(sbi->s_sb, nr_to_scan, ret);
-
-        if (!nr_to_scan)
-                return ret;
-
         spin_lock(&sbi->s_es_lru_lock);
 
         /*
@@ -933,7 +939,7 @@ static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
                         continue;
                 }
 
-                if (ei->i_es_lru_nr == 0)
+                if (ei->i_es_lru_nr == 0 || ei == locked_ei)
                         continue;
 
                 write_lock(&ei->i_es_lock);
@@ -952,6 +958,27 @@ static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
         list_splice_tail(&skiped, &sbi->s_es_lru);
         spin_unlock(&sbi->s_es_lru_lock);
 
+        if (locked_ei && nr_shrunk == 0)
+                nr_shrunk = __es_try_to_reclaim_extents(ei, nr_to_scan);
+
+        return nr_shrunk;
+}
+
+static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
+{
+        struct ext4_sb_info *sbi = container_of(shrink,
+                                        struct ext4_sb_info, s_es_shrinker);
+        int nr_to_scan = sc->nr_to_scan;
+        int ret, nr_shrunk;
+
+        ret = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
+        trace_ext4_es_shrink_enter(sbi->s_sb, nr_to_scan, ret);
+
+        if (!nr_to_scan)
+                return ret;
+
+        nr_shrunk = __ext4_es_shrink(sbi, nr_to_scan, NULL);
+
         ret = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
         trace_ext4_es_shrink_exit(sbi->s_sb, nr_shrunk, ret);
         return ret;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 98b9bff92a8a..ba33c67d6e48 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -514,10 +514,9 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
                   "logical block %lu\n", inode->i_ino, flags, map->m_len,
                   (unsigned long) map->m_lblk);
 
-        ext4_es_lru_add(inode);
-
         /* Lookup extent status tree firstly */
         if (ext4_es_lookup_extent(inode, map->m_lblk, &es)) {
+                ext4_es_lru_add(inode);
                 if (ext4_es_is_written(&es) || ext4_es_is_unwritten(&es)) {
                         map->m_pblk = ext4_es_pblock(&es) +
                                         map->m_lblk - es.es_lblk;
@@ -1529,11 +1528,9 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
                   "logical block %lu\n", inode->i_ino, map->m_len,
                   (unsigned long) map->m_lblk);
 
-        ext4_es_lru_add(inode);
-
         /* Lookup extent status tree firstly */
         if (ext4_es_lookup_extent(inode, iblock, &es)) {
-
+                ext4_es_lru_add(inode);
                 if (ext4_es_is_hole(&es)) {
                         retval = 0;
                         down_read((&EXT4_I(inode)->i_data_sem));