btrfs: convert pr_* to btrfs_* where possible

For many printks, we want to know which file system issued the message.

This patch converts most pr_* calls to use the btrfs_* versions instead.
In some cases, this means adding plumbing to allow call sites access to
an fs_info pointer.

fs/btrfs/check-integrity.c is left alone for another day.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 0128bc3..74ed5aa 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1148,7 +1148,7 @@
 	sb->s_iflags |= SB_I_CGROUPWB;
 	err = open_ctree(sb, fs_devices, (char *)data);
 	if (err) {
-		pr_err("BTRFS: open_ctree failed\n");
+		btrfs_err(fs_info, "open_ctree failed");
 		return err;
 	}
 
@@ -1446,12 +1446,13 @@
 
 	if (!IS_ERR(root)) {
 		struct super_block *s = root->d_sb;
+		struct btrfs_fs_info *fs_info = btrfs_sb(s);
 		struct inode *root_inode = d_inode(root);
 		u64 root_objectid = BTRFS_I(root_inode)->root->root_key.objectid;
 
 		ret = 0;
 		if (!is_subvolume_inode(root_inode)) {
-			pr_err("BTRFS: '%s' is not a valid subvolume\n",
+			btrfs_err(fs_info, "'%s' is not a valid subvolume",
 			       subvol_name);
 			ret = -EINVAL;
 		}
@@ -1461,8 +1462,9 @@
 			 * subvolume which was passed by ID is renamed and
 			 * another subvolume is renamed over the old location.
 			 */
-			pr_err("BTRFS: subvol '%s' does not match subvolid %llu\n",
-			       subvol_name, subvol_objectid);
+			btrfs_err(fs_info,
+				  "subvol '%s' does not match subvolid %llu",
+				  subvol_name, subvol_objectid);
 			ret = -EINVAL;
 		}
 		if (ret) {