btrfs: Add a new mount option to grow the FS to the limit of the device

Commit Message

Donggeun Kim Aug. 2, 2010, 8:42 a.m. UTC

None

Patch

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index e9bf864..ee71964 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1192,6 +1192,7 @@  struct btrfs_root {
 #define BTRFS_MOUNT_NOSSD		(1 << 9)
 #define BTRFS_MOUNT_DISCARD		(1 << 10)
 #define BTRFS_MOUNT_FORCE_COMPRESS      (1 << 11)
+#define BTRFS_MOUNT_MAXSIZE		(1 << 12)
 
 #define btrfs_clear_opt(o, opt)		((o) &= ~BTRFS_MOUNT_##opt)
 #define btrfs_set_opt(o, opt)		((o) |= BTRFS_MOUNT_##opt)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 34f7c37..a1abf7c 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1533,6 +1533,9 @@  struct btrfs_root *open_ctree(struct super_block *sb,
 	u32 stripesize;
 	u64 generation;
 	u64 features;
+	u64 dev_max_size;
+	u64 dev_old_size;
+	u64 devid;
 	struct btrfs_key location;
 	struct buffer_head *bh;
 	struct btrfs_root *extent_root = kzalloc(sizeof(struct btrfs_root),
@@ -1554,6 +1557,9 @@  struct btrfs_root *open_ctree(struct super_block *sb,
 
 	struct btrfs_super_block *disk_super;
 
+	struct btrfs_trans_handle *trans;
+	struct btrfs_device *device;
+
 	if (!extent_root || !tree_root || !fs_info ||
 	    !chunk_root || !dev_root || !csum_root) {
 		err = -ENOMEM;
@@ -1928,6 +1934,30 @@  struct btrfs_root *open_ctree(struct super_block *sb,
 		btrfs_set_opt(fs_info->mount_opt, SSD);
 	}
 
+	if (btrfs_test_opt(tree_root, MAXSIZE)) {
+		devid = fs_devices->latest_devid;
+		device = btrfs_find_device(tree_root, devid, NULL, NULL);
+		if (!device) {
+			printk(KERN_WARNING "resizer unable to "
+				"find device %llu\n",
+				(unsigned long long)devid);
+			goto fail_trans_kthread;
+		}
+		dev_max_size = device->bdev->bd_inode->i_size;
+		dev_old_size = device->total_bytes;
+		if (dev_max_size > dev_old_size) {
+			trans = btrfs_start_transaction(tree_root, 0);
+			ret = btrfs_grow_device(trans, device, dev_max_size);
+			if (ret)
+				printk(KERN_INFO "unable to resize for %s\n",
+					device->name);
+			else
+				printk(KERN_INFO "new size for %s is %llu\n",
+					device->name, dev_max_size);
+			btrfs_commit_transaction(trans, tree_root);
+		}
+	}
+
 	if (btrfs_super_log_root(disk_super) != 0) {
 		u64 bytenr = btrfs_super_log_root(disk_super);
 
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 859ddaa..d6b8cf2 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -68,7 +68,7 @@  enum {
 	Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd,
 	Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress,
 	Opt_compress_force, Opt_notreelog, Opt_ratio, Opt_flushoncommit,
-	Opt_discard, Opt_err,
+	Opt_discard, Opt_maxsize, Opt_err,
 };
 
 static match_table_t tokens = {
@@ -92,6 +92,7 @@  static match_table_t tokens = {
 	{Opt_flushoncommit, "flushoncommit"},
 	{Opt_ratio, "metadata_ratio=%d"},
 	{Opt_discard, "discard"},
+	{Opt_maxsize, "maxsize"},
 	{Opt_err, NULL},
 };
 
@@ -235,6 +236,9 @@  int btrfs_parse_options(struct btrfs_root *root, char *options)
 		case Opt_discard:
 			btrfs_set_opt(info->mount_opt, DISCARD);
 			break;
+		case Opt_maxsize:
+			btrfs_set_opt(info->mount_opt, MAXSIZE);
+			break;
 		case Opt_err:
 			printk(KERN_INFO "btrfs: unrecognized mount option "
 			       "'%s'\n", p);
@@ -541,6 +545,8 @@  static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
 		seq_puts(seq, ",flushoncommit");
 	if (btrfs_test_opt(root, DISCARD))
 		seq_puts(seq, ",discard");
+	if (btrfs_test_opt(root, MAXSIZE))
+		seq_puts(seq, ",maxsize");
 	if (!(root->fs_info->sb->s_flags & MS_POSIXACL))
 		seq_puts(seq, ",noacl");
 	return 0;