btrfs: move last_flush_error to write_dev_flush and wait_dev_flush

We parallelize the flush command across devices using our own code,
write_dev_flush() sends the flush command to each device and
wait_dev_flush() waits for the flush to complete on all devices. Errors
from each device are recorded at device->last_flush_error and reset to
BLK_STS_OK in write_dev_flush() and to the error, if any, in
wait_dev_flush(). These functions are called from barrier_all_devices().

This patch consolidates the use of device->last_flush_error in
write_dev_flush() and wait_dev_flush() to remove it from
barrier_all_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 1122ed8427b2554fe64926714c20c5cb607410f1..0cb53762474af890345c048b951ca2a4d28001b7 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -4086,6 +4086,8 @@ static void write_dev_flush(struct btrfs_device *device)
 {
        struct bio *bio = &device->flush_bio;
 
+       device->last_flush_error = BLK_STS_OK;
+
 #ifndef CONFIG_BTRFS_FS_CHECK_INTEGRITY
        /*
         * When a disk has write caching disabled, we skip submission of a bio
@@ -4125,6 +4127,11 @@ static blk_status_t wait_dev_flush(struct btrfs_device *device)
        clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
        wait_for_completion_io(&device->flush_wait);
 
+       if (bio->bi_status) {
+               device->last_flush_error = bio->bi_status;
+               btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_FLUSH_ERRS);
+       }
+
        return bio->bi_status;
 }
 
@@ -4159,7 +4166,6 @@ static int barrier_all_devices(struct btrfs_fs_info *info)
                        continue;
 
                write_dev_flush(dev);
-               dev->last_flush_error = BLK_STS_OK;
        }
 
        /* wait for all the barriers */
@@ -4175,12 +4181,8 @@ static int barrier_all_devices(struct btrfs_fs_info *info)
                        continue;
 
                ret = wait_dev_flush(dev);
-               if (ret) {
-                       dev->last_flush_error = ret;
-                       btrfs_dev_stat_inc_and_print(dev,
-                                       BTRFS_DEV_STAT_FLUSH_ERRS);
+               if (ret)
                        errors_wait++;
-               }
        }
 
        if (errors_wait) {