Btrfs: pass fs_info instead of root

A small number of functions that are used in a device replace
procedure when the operation is resumed at mount time are unable
to pass the same root pointer that would be used in the regular
(ioctl) context. And since the root pointer is not required, only
the fs_info is, the root pointer argument is replaced with the
fs_info pointer argument.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 12 insertions, 11 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 6cd8a32c448..d2c0bccca60 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1398,7 +1398,7 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
 		disk_super = (struct btrfs_super_block *)bh->b_data;
 		devid = btrfs_stack_device_id(&disk_super->dev_item);
 		dev_uuid = disk_super->dev_item.uuid;
-		device = btrfs_find_device(root, devid, dev_uuid,
+		device = btrfs_find_device(root->fs_info, devid, dev_uuid,
 					   disk_super->fsid);
 		if (!device) {
 			ret = -ENOENT;
@@ -1435,7 +1435,7 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
 	spin_unlock(&root->fs_info->free_chunk_lock);
 
 	device->in_fs_metadata = 0;
-	btrfs_scrub_cancel_dev(root, device);
+	btrfs_scrub_cancel_dev(root->fs_info, device);
 
 	/*
 	 * the device list mutex makes sure that we don't change
@@ -1492,7 +1492,7 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
 	 * at this point, the device is zero sized.  We want to
 	 * remove it from the devices list and zero out the old super
 	 */
-	if (clear_super) {
+	if (clear_super && disk_super) {
 		/* make sure this device isn't detected as part of
 		 * the FS anymore
 		 */
@@ -1540,7 +1540,7 @@ int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
 	disk_super = (struct btrfs_super_block *)bh->b_data;
 	devid = btrfs_stack_device_id(&disk_super->dev_item);
 	dev_uuid = disk_super->dev_item.uuid;
-	*device = btrfs_find_device(root, devid, dev_uuid,
+	*device = btrfs_find_device(root->fs_info, devid, dev_uuid,
 				    disk_super->fsid);
 	brelse(bh);
 	if (!*device)
@@ -1699,7 +1699,8 @@ next_slot:
 		read_extent_buffer(leaf, fs_uuid,
 				   (unsigned long)btrfs_device_fsid(dev_item),
 				   BTRFS_UUID_SIZE);
-		device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
+		device = btrfs_find_device(root->fs_info, devid, dev_uuid,
+					   fs_uuid);
 		BUG_ON(!device); /* Logic error */
 
 		if (device->fs_devices->seeding) {
@@ -4463,13 +4464,13 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 	return 0;
 }
 
-struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
+struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
 				       u8 *uuid, u8 *fsid)
 {
 	struct btrfs_device *device;
 	struct btrfs_fs_devices *cur_devices;
 
-	cur_devices = root->fs_info->fs_devices;
+	cur_devices = fs_info->fs_devices;
 	while (cur_devices) {
 		if (!fsid ||
 		    !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
@@ -4567,8 +4568,8 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
 		read_extent_buffer(leaf, uuid, (unsigned long)
 				   btrfs_stripe_dev_uuid_nr(chunk, i),
 				   BTRFS_UUID_SIZE);
-		map->stripes[i].dev = btrfs_find_device(root, devid, uuid,
-							NULL);
+		map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
+							uuid, NULL);
 		if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
 			kfree(map);
 			free_extent_map(em);
@@ -4686,7 +4687,7 @@ static int read_one_dev(struct btrfs_root *root,
 			return ret;
 	}
 
-	device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
+	device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
 	if (!device || !device->bdev) {
 		if (!btrfs_test_opt(root, DEGRADED))
 			return -EIO;
@@ -5078,7 +5079,7 @@ int btrfs_get_dev_stats(struct btrfs_root *root,
 	int i;
 
 	mutex_lock(&fs_devices->device_list_mutex);
-	dev = btrfs_find_device(root, stats->devid, NULL, NULL);
+	dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
 	mutex_unlock(&fs_devices->device_list_mutex);
 
 	if (!dev) {