direct-io: Implement generic deferred AIO completions

[~andy/linux] / fs / ext4 / extents_status.c

diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index 4b8df7fbb10aacc955248d6adc68fc46202e2d5b..91cb110da1b4fe6fe9e334073ddae337507cd5d6 100644 (file)
--- 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;