Btrfs: enhance btrfs_scratch_superblock to scratch all superblocks

This patch updates and renames btrfs_scratch_superblocks, (which is used
by the replace device thread), with those fixes from the scratch
superblock code section of btrfs_rm_device(). The fixes are:
  Scratch all copies of superblock
  Notify kobject that superblock has been changed
  Update time on the device

So that btrfs_rm_device() can use the function
btrfs_scratch_superblocks() instead of its own scratch code. And further
replace deivce code which similarly releases device back to the system,
will have the fixes from the btrfs device delete.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
[renamed to btrfs_scratch_superblock]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index c3e2591..1cde784 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1924,7 +1924,8 @@ void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
        if (srcdev->writeable) {
                fs_devices->rw_devices--;
                /* zero out the old super if it is writable */
-               btrfs_scratch_superblock(srcdev);
+               btrfs_scratch_superblocks(srcdev->bdev,
+                                       rcu_str_deref(srcdev->name));
        }
 
        if (srcdev->bdev)
@@ -1974,7 +1975,8 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
        btrfs_sysfs_rm_device_link(fs_info->fs_devices, tgtdev);
 
        if (tgtdev->bdev) {
-               btrfs_scratch_superblock(tgtdev);
+               btrfs_scratch_superblocks(tgtdev->bdev,
+                                       rcu_str_deref(tgtdev->name));
                fs_info->fs_devices->open_devices--;
        }
        fs_info->fs_devices->num_devices--;
@@ -6738,22 +6740,34 @@ int btrfs_get_dev_stats(struct btrfs_root *root,
        return 0;
 }
 
-int btrfs_scratch_superblock(struct btrfs_device *device)
+void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path)
 {
        struct buffer_head *bh;
        struct btrfs_super_block *disk_super;
+       int copy_num;
 
-       bh = btrfs_read_dev_super(device->bdev);
-       if (IS_ERR(bh))
-               return PTR_ERR(bh);
-       disk_super = (struct btrfs_super_block *)bh->b_data;
+       if (!bdev)
+               return;
 
-       memset(&disk_super->magic, 0, sizeof(disk_super->magic));
-       set_buffer_dirty(bh);
-       sync_dirty_buffer(bh);
-       brelse(bh);
+       for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX;
+               copy_num++) {
 
-       return 0;
+               if (btrfs_read_dev_one_super(bdev, copy_num, &bh))
+                       continue;
+
+               disk_super = (struct btrfs_super_block *)bh->b_data;
+
+               memset(&disk_super->magic, 0, sizeof(disk_super->magic));
+               set_buffer_dirty(bh);
+               sync_dirty_buffer(bh);
+               brelse(bh);
+       }
+
+       /* Notify udev that device has changed */
+       btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
+
+       /* Update ctime/mtime for device path for libblkid */
+       update_dev_time(device_path);
 }
 
 /*

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 413a70c..8663bf7 100644 (file)
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -474,7 +474,7 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
                                      struct btrfs_device *tgtdev);
 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
                                              struct btrfs_device *tgtdev);
-int btrfs_scratch_superblock(struct btrfs_device *device);
+void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path);
 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
                           u64 logical, u64 len, int mirror_num);
 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,