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: Andrei Popa <andrei.popa@i-neo.ro>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 0fadcdb..915ac14 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -413,7 +413,15 @@
btrfs_set_opt(info->mount_opt, NODATASUM);
break;
case Opt_nodatacow:
- printk(KERN_INFO "btrfs: setting nodatacow\n");
+ 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 @@
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";