btrfs-progs: Add new option for specify chunk root bytenr

[platform/upstream/btrfs-progs.git] / disk-io.c

diff --git a/disk-io.c b/disk-io.c
index e520d80..88015b7 100644 (file)
--- a/disk-io.c
+++ b/disk-io.c
@@ -1146,7 +1146,8 @@ int btrfs_scan_fs_devices(int fd, const char *path,
        return 0;
 }
 
-int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info)
+int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info,
+                                         u64 chunk_root_bytenr)
 {
        struct btrfs_super_block *sb = fs_info->super_copy;
        u32 sectorsize;
@@ -1173,8 +1174,20 @@ int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info)
                                     btrfs_super_chunk_root_level(sb));
        generation = btrfs_super_chunk_root_generation(sb);
 
+       if (chunk_root_bytenr && !IS_ALIGNED(chunk_root_bytenr,
+                                           btrfs_super_sectorsize(sb))) {
+               warning("chunk_root_bytenr %llu is unaligned to %u, ignore it",
+                       chunk_root_bytenr, btrfs_super_sectorsize(sb));
+               chunk_root_bytenr = 0;
+       }
+
+       if (!chunk_root_bytenr)
+               chunk_root_bytenr = btrfs_super_chunk_root(sb);
+       else
+               generation = 0;
+
        fs_info->chunk_root->node = read_tree_block(fs_info->chunk_root,
-                                                   btrfs_super_chunk_root(sb),
+                                                   chunk_root_bytenr,
                                                    blocksize, generation);
        if (!extent_buffer_uptodate(fs_info->chunk_root->node)) {
                if (fs_info->ignore_chunk_tree_error) {
@@ -1200,6 +1213,7 @@ int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info)
 static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
                                             u64 sb_bytenr,
                                             u64 root_tree_bytenr,
+                                            u64 chunk_root_bytenr,
                                             enum btrfs_open_ctree_flags flags)
 {
        struct btrfs_fs_info *fs_info;
@@ -1273,7 +1287,7 @@ static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
        if (ret)
                goto out_devices;
 
-       ret = btrfs_setup_chunk_tree_and_device_map(fs_info);
+       ret = btrfs_setup_chunk_tree_and_device_map(fs_info, chunk_root_bytenr);
        if (ret)
                goto out_chunk;
 
@@ -1305,6 +1319,7 @@ out:
 
 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
                                         u64 sb_bytenr, u64 root_tree_bytenr,
+                                        u64 chunk_root_bytenr,
                                         enum btrfs_open_ctree_flags flags)
 {
        int fp;
@@ -1320,7 +1335,7 @@ struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
                return NULL;
        }
        info = __open_ctree_fd(fp, filename, sb_bytenr, root_tree_bytenr,
-                              flags);
+                              chunk_root_bytenr, flags);
        close(fp);
        return info;
 }
@@ -1332,7 +1347,7 @@ struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
 
        /* This flags may not return fs_info with any valid root */
        BUG_ON(flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
-       info = open_ctree_fs_info(filename, sb_bytenr, 0, flags);
+       info = open_ctree_fs_info(filename, sb_bytenr, 0, 0, flags);
        if (!info)
                return NULL;
        if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
@@ -1347,7 +1362,7 @@ struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
 
        /* This flags may not return fs_info with any valid root */
        BUG_ON(flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
-       info = __open_ctree_fd(fp, path, sb_bytenr, 0, flags);
+       info = __open_ctree_fd(fp, path, sb_bytenr, 0, 0, flags);
        if (!info)
                return NULL;
        if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)