ext4: split extent conversion lists to reserved & unreserved parts

Now that we have extent conversions with reserved transaction, we have
to prevent extent conversions without reserved transaction (from DIO
code) to block these (as that would effectively void any transaction
reservation we did).  So split lists, work items, and work queues to
reserved and unreserved parts.

Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 27 insertions, 11 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index eac4d3081ba4..7c8e1713e203 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -750,8 +750,10 @@ static void ext4_put_super(struct super_block *sb)
         ext4_unregister_li_request(sb);
         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 
-        flush_workqueue(sbi->dio_unwritten_wq);
-        destroy_workqueue(sbi->dio_unwritten_wq);
+        flush_workqueue(sbi->unrsv_conversion_wq);
+        flush_workqueue(sbi->rsv_conversion_wq);
+        destroy_workqueue(sbi->unrsv_conversion_wq);
+        destroy_workqueue(sbi->rsv_conversion_wq);
 
         if (sbi->s_journal) {
                 err = jbd2_journal_destroy(sbi->s_journal);
@@ -859,13 +861,15 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
         ei->i_reserved_quota = 0;
 #endif
         ei->jinode = NULL;
-        INIT_LIST_HEAD(&ei->i_completed_io_list);
+        INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
+        INIT_LIST_HEAD(&ei->i_unrsv_conversion_list);
         spin_lock_init(&ei->i_completed_io_lock);
         ei->i_sync_tid = 0;
         ei->i_datasync_tid = 0;
         atomic_set(&ei->i_ioend_count, 0);
         atomic_set(&ei->i_unwritten, 0);
-        INIT_WORK(&ei->i_unwritten_work, ext4_end_io_work);
+        INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
+        INIT_WORK(&ei->i_unrsv_conversion_work, ext4_end_io_unrsv_work);
 
         return &ei->vfs_inode;
 }
@@ -3936,12 +3940,20 @@ no_journal:
          * The maximum number of concurrent works can be high and
          * concurrency isn't really necessary.  Limit it to 1.
          */
-        EXT4_SB(sb)->dio_unwritten_wq =
-                alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
-        if (!EXT4_SB(sb)->dio_unwritten_wq) {
-                printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
+        EXT4_SB(sb)->rsv_conversion_wq =
+                alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
+        if (!EXT4_SB(sb)->rsv_conversion_wq) {
+                printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
                 ret = -ENOMEM;
-                goto failed_mount_wq;
+                goto failed_mount4;
+        }
+
+        EXT4_SB(sb)->unrsv_conversion_wq =
+                alloc_workqueue("ext4-unrsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
+        if (!EXT4_SB(sb)->unrsv_conversion_wq) {
+                printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
+                ret = -ENOMEM;
+                goto failed_mount4;
         }
 
         /*
@@ -4095,7 +4107,10 @@ failed_mount4a:
         sb->s_root = NULL;
 failed_mount4:
         ext4_msg(sb, KERN_ERR, "mount failed");
-        destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
+        if (EXT4_SB(sb)->rsv_conversion_wq)
+                destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
+        if (EXT4_SB(sb)->unrsv_conversion_wq)
+                destroy_workqueue(EXT4_SB(sb)->unrsv_conversion_wq);
 failed_mount_wq:
         if (sbi->s_journal) {
                 jbd2_journal_destroy(sbi->s_journal);
@@ -4541,7 +4556,8 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
         struct ext4_sb_info *sbi = EXT4_SB(sb);
 
         trace_ext4_sync_fs(sb, wait);
-        flush_workqueue(sbi->dio_unwritten_wq);
+        flush_workqueue(sbi->rsv_conversion_wq);
+        flush_workqueue(sbi->unrsv_conversion_wq);
         /*
          * Writeback quota in non-journalled quota case - journalled quota has
          * no dirty dquots