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()

Author: torvalds

fs/ext4/extents.c

@@ -2835,6 +2835,9 @@ int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
 				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 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 		/* 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 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 	}
 
 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,

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;

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));