btrfs: add_missing_dev() should return the actual error

add_missing_dev() can return device pointer so that IS_ERR/PTR_ERR can
be used to check for the actual error that occurred in the function.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
[ minor error message adjustment ]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 763d04b4e5b74f7b754b9c24d1cfd63efdf46fe2..23b628cfad198e3d8141aa0959c45ec1a582f171 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6238,7 +6238,7 @@ static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices,
 
        device = btrfs_alloc_device(NULL, &devid, dev_uuid);
        if (IS_ERR(device))
-               return NULL;
+               return device;
 
        list_add(&device->dev_list, &fs_devices->devices);
        device->fs_devices = fs_devices;
@@ -6443,9 +6443,12 @@ static int read_one_chunk(struct btrfs_fs_info *fs_info, struct btrfs_key *key,
                        map->stripes[i].dev =
                                add_missing_dev(fs_info->fs_devices, devid,
                                                uuid);
-                       if (!map->stripes[i].dev) {
+                       if (IS_ERR(map->stripes[i].dev)) {
                                free_extent_map(em);
-                               return -EIO;
+                               btrfs_err(fs_info,
+                                       "failed to init missing dev %llu: %ld",
+                                       devid, PTR_ERR(map->stripes[i].dev));
+                               return PTR_ERR(map->stripes[i].dev);
                        }
                        btrfs_report_missing_device(fs_info, devid, uuid);
                }
@@ -6571,8 +6574,12 @@ static int read_one_dev(struct btrfs_fs_info *fs_info,
                }
 
                device = add_missing_dev(fs_devices, devid, dev_uuid);
-               if (!device)
-                       return -ENOMEM;
+               if (IS_ERR(device)) {
+                       btrfs_err(fs_info,
+                               "failed to add missing dev %llu: %ld",
+                               devid, PTR_ERR(device));
+                       return PTR_ERR(device);
+               }
                btrfs_report_missing_device(fs_info, devid, dev_uuid);
        } else {
                if (!device->bdev) {