btrfs: read raid stripe tree from disk

If we find the raid-stripe-tree on mount, read it from disk. This is
a backward incompatible feature. The rescue=ignorebadroots mount option
will skip this tree.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/block-rsv.c b/fs/btrfs/block-rsv.c
index 6a8f9629bbbd730a28c51387fa951b1e741740eb..ceb5f586a2d55571d53db2de227f4ef0f5ec1c27 100644 (file)
--- a/fs/btrfs/block-rsv.c
+++ b/fs/btrfs/block-rsv.c
@@ -356,6 +356,11 @@ void btrfs_update_global_block_rsv(struct btrfs_fs_info *fs_info)
                min_items++;
        }
 
+       if (btrfs_fs_incompat(fs_info, RAID_STRIPE_TREE)) {
+               num_bytes += btrfs_root_used(&fs_info->stripe_root->root_item);
+               min_items++;
+       }
+
        /*
         * But we also want to reserve enough space so we can do the fallback
         * global reserve for an unlink, which is an additional
@@ -407,6 +412,7 @@ void btrfs_init_root_block_rsv(struct btrfs_root *root)
        case BTRFS_EXTENT_TREE_OBJECTID:
        case BTRFS_FREE_SPACE_TREE_OBJECTID:
        case BTRFS_BLOCK_GROUP_TREE_OBJECTID:
+       case BTRFS_RAID_STRIPE_TREE_OBJECTID:
                root->block_rsv = &fs_info->delayed_refs_rsv;
                break;
        case BTRFS_ROOT_TREE_OBJECTID:

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 163f37ad1b270dd20454bd932915aa2715e90bc9..dc577b3c53f6c237742ebdf51a35818bdee6a87a 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1179,6 +1179,8 @@ static struct btrfs_root *btrfs_get_global_root(struct btrfs_fs_info *fs_info,
                return btrfs_grab_root(fs_info->block_group_root);
        case BTRFS_FREE_SPACE_TREE_OBJECTID:
                return btrfs_grab_root(btrfs_global_root(fs_info, &key));
+       case BTRFS_RAID_STRIPE_TREE_OBJECTID:
+               return btrfs_grab_root(fs_info->stripe_root);
        default:
                return NULL;
        }
@@ -1259,6 +1261,7 @@ void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
        btrfs_put_root(fs_info->fs_root);
        btrfs_put_root(fs_info->data_reloc_root);
        btrfs_put_root(fs_info->block_group_root);
+       btrfs_put_root(fs_info->stripe_root);
        btrfs_check_leaked_roots(fs_info);
        btrfs_extent_buffer_leak_debug_check(fs_info);
        kfree(fs_info->super_copy);
@@ -1804,6 +1807,7 @@ static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root)
        free_root_extent_buffers(info->fs_root);
        free_root_extent_buffers(info->data_reloc_root);
        free_root_extent_buffers(info->block_group_root);
+       free_root_extent_buffers(info->stripe_root);
        if (free_chunk_root)
                free_root_extent_buffers(info->chunk_root);
 }
@@ -2280,6 +2284,20 @@ static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
                fs_info->uuid_root = root;
        }
 
+       if (btrfs_fs_incompat(fs_info, RAID_STRIPE_TREE)) {
+               location.objectid = BTRFS_RAID_STRIPE_TREE_OBJECTID;
+               root = btrfs_read_tree_root(tree_root, &location);
+               if (IS_ERR(root)) {
+                       if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
+                               ret = PTR_ERR(root);
+                               goto out;
+                       }
+               } else {
+                       set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+                       fs_info->stripe_root = root;
+               }
+       }
+
        return 0;
 out:
        btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",

diff --git a/fs/btrfs/fs.h b/fs/btrfs/fs.h
index 5559c33cd53a50d078986a7e30507521087f5896..b1914a9eb9f62cefa8dd8eb3687d37c01de118bd 100644 (file)
--- a/fs/btrfs/fs.h
+++ b/fs/btrfs/fs.h
@@ -373,6 +373,7 @@ struct btrfs_fs_info {
        struct btrfs_root *uuid_root;
        struct btrfs_root *data_reloc_root;
        struct btrfs_root *block_group_root;
+       struct btrfs_root *stripe_root;
 
        /* The log root tree is a directory of all the other log roots */
        struct btrfs_root *log_root_tree;

diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index dbb8b96da50d3088489c3055f58ac992cb3b3ba9..b9a1d9af8ae8d3ed325efcdf871537f1c34c93f2 100644 (file)
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -333,6 +333,7 @@ struct btrfs_ioctl_fs_info_args {
 #define BTRFS_FEATURE_INCOMPAT_RAID1C34                (1ULL << 11)
 #define BTRFS_FEATURE_INCOMPAT_ZONED           (1ULL << 12)
 #define BTRFS_FEATURE_INCOMPAT_EXTENT_TREE_V2  (1ULL << 13)
+#define BTRFS_FEATURE_INCOMPAT_RAID_STRIPE_TREE        (1ULL << 14)
 
 struct btrfs_ioctl_feature_flags {
        __u64 compat_flags;