Commit bedb2cca authored by Andrei Popa's avatar Andrei Popa Committed by Chris Mason
Browse files

Btrfs: make compress and nodatacow mount options mutually exclusive 



If a filesystem is mounted with compression and then remounted by adding nodatacow,
the compression is disabled but the compress flag is still visible.
Also, if a filesystem is mounted with nodatacow and then remounted with compression,
nodatacow flag is still present but it's not active.
This patch:
- removes compress flags and notifies that the compression has been disabled if the
  filesystem is mounted with nodatacow
- removes nodatacow and nodatasum flags if mounted with compress.

Signed-off-by: default avatarAndrei Popa <andrei.popa@i-neo.ro>
parent 48940662

fs/btrfs/super.c

+13 −1
Original line number Diff line number Diff line
@@ -413,7 +413,15 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) 
			btrfs_set_opt(info->mount_opt, NODATASUM);

			break;

		case Opt_nodatacow:

			if (!btrfs_test_opt(root, COMPRESS) ||

				!btrfs_test_opt(root, FORCE_COMPRESS)) {

					printk(KERN_INFO "btrfs: setting nodatacow, compression disabled\n");

			} else {

				printk(KERN_INFO "btrfs: setting nodatacow\n");

			}

			info->compress_type = BTRFS_COMPRESS_NONE;

			btrfs_clear_opt(info->mount_opt, COMPRESS);

			btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS);

			btrfs_set_opt(info->mount_opt, NODATACOW);

			btrfs_set_opt(info->mount_opt, NODATASUM);

			break;
@@ -428,10 +436,14 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) 
				compress_type = "zlib";

				info->compress_type = BTRFS_COMPRESS_ZLIB;

				btrfs_set_opt(info->mount_opt, COMPRESS);

				btrfs_clear_opt(info->mount_opt, NODATACOW);

				btrfs_clear_opt(info->mount_opt, NODATASUM);

			} else if (strcmp(args[0].from, "lzo") == 0) {

				compress_type = "lzo";

				info->compress_type = BTRFS_COMPRESS_LZO;

				btrfs_set_opt(info->mount_opt, COMPRESS);

				btrfs_clear_opt(info->mount_opt, NODATACOW);

				btrfs_clear_opt(info->mount_opt, NODATASUM);

				btrfs_set_fs_incompat(info, COMPRESS_LZO);

			} else if (strncmp(args[0].from, "no", 2) == 0) {

				compress_type = "no";

CRA Git | Maintained and supported by SUSTech CRA and CCSE