ext4: each filesystem creates and uses its own mb_cache

This patch adds new interfaces to create and destory cache,
ext4_xattr_create_cache() and ext4_xattr_destroy_cache(), and remove
the cache creation and destory calls from ex4_init_xattr() and
ext4_exitxattr() in fs/ext4/xattr.c.

fs/ext4/super.c has been changed so that when a filesystem is mounted
a cache is allocated and attched to its ext4_sb_info structure.

fs/mbcache.c has been changed so that only one slab allocator is
allocated and used by all mbcache structures.

Signed-off-by: T. Makphaibulchoke <tmac@hp.com>

1 files changed, 17 insertions, 8 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 89baee42f353..5a51af7d0335 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -59,6 +59,7 @@ static struct kset *ext4_kset;
 static struct ext4_lazy_init *ext4_li_info;
 static struct mutex ext4_li_mtx;
 static struct ext4_features *ext4_feat;
+static int ext4_mballoc_ready;
 
 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
                              unsigned long journal_devnum);
@@ -845,6 +846,10 @@ static void ext4_put_super(struct super_block *sb)
                 invalidate_bdev(sbi->journal_bdev);
                 ext4_blkdev_remove(sbi);
         }
+        if (sbi->s_mb_cache) {
+                ext4_xattr_destroy_cache(sbi->s_mb_cache);
+                sbi->s_mb_cache = NULL;
+        }
         if (sbi->s_mmp_tsk)
                 kthread_stop(sbi->s_mmp_tsk);
         sb->s_fs_info = NULL;
@@ -4010,6 +4015,14 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
 
 no_journal:
+        if (ext4_mballoc_ready) {
+                sbi->s_mb_cache = ext4_xattr_create_cache(sb->s_id);
+                if (!sbi->s_mb_cache) {
+                        ext4_msg(sb, KERN_ERR, "Failed to create an mb_cache");
+                        goto failed_mount_wq;
+                }
+        }
+
         /*
          * Get the # of file system overhead blocks from the
          * superblock if present.
@@ -5519,11 +5532,9 @@ static int __init ext4_init_fs(void)
 
         err = ext4_init_mballoc();
         if (err)
-                goto out3;
-
-        err = ext4_init_xattr();
-        if (err)
                 goto out2;
+        else
+                ext4_mballoc_ready = 1;
         err = init_inodecache();
         if (err)
                 goto out1;
@@ -5539,10 +5550,9 @@ out:
         unregister_as_ext3();
         destroy_inodecache();
 out1:
-        ext4_exit_xattr();
-out2:
+        ext4_mballoc_ready = 0;
         ext4_exit_mballoc();
-out3:
+out2:
         ext4_exit_feat_adverts();
 out4:
         if (ext4_proc_root)
@@ -5565,7 +5575,6 @@ static void __exit ext4_exit_fs(void)
         unregister_as_ext3();
         unregister_filesystem(&ext4_fs_type);
         destroy_inodecache();
-        ext4_exit_xattr();
         ext4_exit_mballoc();
         ext4_exit_feat_adverts();
         remove_proc_entry("fs/ext4", NULL);