btrfs: log, when replace, is canceled by the user

For debugging or administration purposes, we would want to know if and
when the user cancels the replace, to complement the existing messages
when dev-replace starts or finishes.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog, fold fix for RCU warning from Nikolay ]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index c523478b3de2298e45c5b58e8671b9b58b499fac..e279f04b338889361a11e5d26a06feea948ee13d 100644 (file)
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -703,6 +703,7 @@ int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
 {
        struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
        struct btrfs_device *tgt_device = NULL;
+       struct btrfs_device *src_device = NULL;
        struct btrfs_trans_handle *trans;
        struct btrfs_root *root = fs_info->tree_root;
        int result;
@@ -724,6 +725,7 @@ int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
        case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
                result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
                tgt_device = dev_replace->tgtdev;
+               src_device = dev_replace->srcdev;
                dev_replace->tgtdev = NULL;
                dev_replace->srcdev = NULL;
                break;
@@ -741,6 +743,12 @@ int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
        }
        ret = btrfs_commit_transaction(trans);
        WARN_ON(ret);
+
+       btrfs_info_in_rcu(fs_info,
+               "dev_replace from %s (devid %llu) to %s canceled",
+               btrfs_dev_name(src_device), src_device->devid,
+               btrfs_dev_name(tgt_device));
+
        if (tgt_device)
                btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);