Signed-off-by: Wang Sheng-Hui <[email protected]>
---
 Makefile          |    4 +-
 btrfs-find-root.c |  454 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 find-root.c       |  454 -----------------------------------------------------
 3 files changed, 456 insertions(+), 456 deletions(-)
 create mode 100644 btrfs-find-root.c
 delete mode 100644 find-root.c

diff --git a/Makefile b/Makefile
index f4bb782..833dddf 100644
--- a/Makefile
+++ b/Makefile
@@ -48,8 +48,8 @@ btrfs: $(objects) btrfs.o help.o common.o $(cmds_objects)
 calc-size: $(objects) calc-size.o
        $(CC) $(CFLAGS) -o calc-size calc-size.o $(objects) $(LDFLAGS) $(LIBS)

-btrfs-find-root: $(objects) find-root.o
-       $(CC) $(CFLAGS) -o btrfs-find-root find-root.o $(objects) $(LDFLAGS) 
$(LIBS)
+btrfs-find-root: $(objects) btrfs-find-root.o
+       $(CC) $(CFLAGS) -o btrfs-find-root btrfs-find-root.o $(objects) 
$(LDFLAGS) $(LIBS)

 btrfs-restore: $(objects) restore.o
        $(CC) $(CFLAGS) -o btrfs-restore restore.o $(objects) $(LDFLAGS) 
$(LIBS) $(RESTORE_LIBS)
diff --git a/btrfs-find-root.c b/btrfs-find-root.c
new file mode 100644
index 0000000..2fb40e5
--- /dev/null
+++ b/btrfs-find-root.c
@@ -0,0 +1,454 @@
+/*
+ * Copyright (C) 2011 Red Hat.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#define _XOPEN_SOURCE 500
+#define _GNU_SOURCE 1
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <zlib.h>
+#include "kerncompat.h"
+#include "ctree.h"
+#include "disk-io.h"
+#include "print-tree.h"
+#include "transaction.h"
+#include "list.h"
+#include "version.h"
+#include "volumes.h"
+#include "utils.h"
+#include "crc32c.h"
+
+static u16 csum_size = 0;
+static u64 search_objectid = BTRFS_ROOT_TREE_OBJECTID;
+
+static void usage()
+{
+       fprintf(stderr, "Usage: find-roots [-o search_objectid] <device>\n");
+}
+
+int csum_block(void *buf, u32 len)
+{
+       char *result;
+       u32 crc = ~(u32)0;
+       int ret = 0;
+
+       result = malloc(csum_size * sizeof(char));
+       if (!result) {
+               fprintf(stderr, "No memory\n");
+               return 1;
+       }
+
+       len -= BTRFS_CSUM_SIZE;
+       crc = crc32c(crc, buf + BTRFS_CSUM_SIZE, len);
+       btrfs_csum_final(crc, result);
+
+       if (memcmp(buf, result, csum_size))
+               ret = 1;
+       free(result);
+       return ret;
+}
+
+static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
+                       u32 stripesize, struct btrfs_root *root,
+                       struct btrfs_fs_info *fs_info, u64 objectid)
+{
+       root->node = NULL;
+       root->commit_root = NULL;
+       root->sectorsize = sectorsize;
+       root->nodesize = nodesize;
+       root->leafsize = leafsize;
+       root->stripesize = stripesize;
+       root->ref_cows = 0;
+       root->track_dirty = 0;
+
+       root->fs_info = fs_info;
+       root->objectid = objectid;
+       root->last_trans = 0;
+       root->highest_inode = 0;
+       root->last_inode_alloc = 0;
+
+       INIT_LIST_HEAD(&root->dirty_list);
+       memset(&root->root_key, 0, sizeof(root->root_key));
+       memset(&root->root_item, 0, sizeof(root->root_item));
+       root->root_key.objectid = objectid;
+       return 0;
+}
+
+static int close_all_devices(struct btrfs_fs_info *fs_info)
+{
+       struct list_head *list;
+       struct list_head *next;
+       struct btrfs_device *device;
+
+       return 0;
+
+       list = &fs_info->fs_devices->devices;
+       list_for_each(next, list) {
+               device = list_entry(next, struct btrfs_device, dev_list);
+               close(device->fd);
+       }
+       return 0;
+}
+
+static struct btrfs_root *open_ctree_broken(int fd, const char *device)
+{
+       u32 sectorsize;
+       u32 nodesize;
+       u32 leafsize;
+       u32 blocksize;
+       u32 stripesize;
+       u64 generation;
+       struct btrfs_root *tree_root = malloc(sizeof(struct btrfs_root));
+       struct btrfs_root *extent_root = malloc(sizeof(struct btrfs_root));
+       struct btrfs_root *chunk_root = malloc(sizeof(struct btrfs_root));
+       struct btrfs_root *dev_root = malloc(sizeof(struct btrfs_root));
+       struct btrfs_root *csum_root = malloc(sizeof(struct btrfs_root));
+       struct btrfs_fs_info *fs_info = malloc(sizeof(*fs_info));
+       int ret;
+       struct btrfs_super_block *disk_super;
+       struct btrfs_fs_devices *fs_devices = NULL;
+       u64 total_devs;
+       u64 features;
+
+       ret = btrfs_scan_one_device(fd, device, &fs_devices,
+                                   &total_devs, BTRFS_SUPER_INFO_OFFSET);
+
+       if (ret) {
+               fprintf(stderr, "No valid Btrfs found on %s\n", device);
+               goto out;
+       }
+
+       if (total_devs != 1) {
+               ret = btrfs_scan_for_fsid(fs_devices, total_devs, 1);
+               if (ret)
+                       goto out;
+       }
+
+       memset(fs_info, 0, sizeof(*fs_info));
+       fs_info->tree_root = tree_root;
+       fs_info->extent_root = extent_root;
+       fs_info->chunk_root = chunk_root;
+       fs_info->dev_root = dev_root;
+       fs_info->csum_root = csum_root;
+
+       fs_info->readonly = 1;
+
+       extent_io_tree_init(&fs_info->extent_cache);
+       extent_io_tree_init(&fs_info->free_space_cache);
+       extent_io_tree_init(&fs_info->block_group_cache);
+       extent_io_tree_init(&fs_info->pinned_extents);
+       extent_io_tree_init(&fs_info->pending_del);
+       extent_io_tree_init(&fs_info->extent_ins);
+       cache_tree_init(&fs_info->fs_root_cache);
+
+       cache_tree_init(&fs_info->mapping_tree.cache_tree);
+
+       mutex_init(&fs_info->fs_mutex);
+       fs_info->fs_devices = fs_devices;
+       INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
+       INIT_LIST_HEAD(&fs_info->space_info);
+
+       __setup_root(4096, 4096, 4096, 4096, tree_root,
+                    fs_info, BTRFS_ROOT_TREE_OBJECTID);
+
+       ret = btrfs_open_devices(fs_devices, O_RDONLY);
+       if (ret)
+               goto out_cleanup;
+
+       fs_info->super_bytenr = BTRFS_SUPER_INFO_OFFSET;
+       disk_super = &fs_info->super_copy;
+       ret = btrfs_read_dev_super(fs_devices->latest_bdev,
+                                  disk_super, BTRFS_SUPER_INFO_OFFSET);
+       if (ret) {
+               printk("No valid btrfs found\n");
+               goto out_devices;
+       }
+
+       memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
+
+
+       features = btrfs_super_incompat_flags(disk_super) &
+                  ~BTRFS_FEATURE_INCOMPAT_SUPP;
+       if (features) {
+               printk("couldn't open because of unsupported "
+                      "option features (%Lx).\n", features);
+               goto out_devices;
+       }
+
+       features = btrfs_super_incompat_flags(disk_super);
+       if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
+               features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
+               btrfs_set_super_incompat_flags(disk_super, features);
+       }
+
+       nodesize = btrfs_super_nodesize(disk_super);
+       leafsize = btrfs_super_leafsize(disk_super);
+       sectorsize = btrfs_super_sectorsize(disk_super);
+       stripesize = btrfs_super_stripesize(disk_super);
+       tree_root->nodesize = nodesize;
+       tree_root->leafsize = leafsize;
+       tree_root->sectorsize = sectorsize;
+       tree_root->stripesize = stripesize;
+
+       ret = btrfs_read_sys_array(tree_root);
+       if (ret)
+               goto out_devices;
+       blocksize = btrfs_level_size(tree_root,
+                                    btrfs_super_chunk_root_level(disk_super));
+       generation = btrfs_super_chunk_root_generation(disk_super);
+
+       __setup_root(nodesize, leafsize, sectorsize, stripesize,
+                    chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
+
+       chunk_root->node = read_tree_block(chunk_root,
+                                          btrfs_super_chunk_root(disk_super),
+                                          blocksize, generation);
+       if (!chunk_root->node) {
+               printk("Couldn't read chunk root\n");
+               goto out_devices;
+       }
+
+       read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
+                (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
+                BTRFS_UUID_SIZE);
+
+       if (!(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_METADUMP)) {
+               ret = btrfs_read_chunk_tree(chunk_root);
+               if (ret)
+                       goto out_chunk;
+       }
+
+       return fs_info->chunk_root;
+out_chunk:
+       free_extent_buffer(fs_info->chunk_root->node);
+out_devices:
+       close_all_devices(fs_info);
+out_cleanup:
+       extent_io_tree_cleanup(&fs_info->extent_cache);
+       extent_io_tree_cleanup(&fs_info->free_space_cache);
+       extent_io_tree_cleanup(&fs_info->block_group_cache);
+       extent_io_tree_cleanup(&fs_info->pinned_extents);
+       extent_io_tree_cleanup(&fs_info->pending_del);
+       extent_io_tree_cleanup(&fs_info->extent_ins);
+out:
+       free(tree_root);
+       free(extent_root);
+       free(chunk_root);
+       free(dev_root);
+       free(csum_root);
+       free(fs_info);
+       return NULL;
+}
+
+static int search_iobuf(struct btrfs_root *root, void *iobuf,
+                       size_t iobuf_size, off_t offset)
+{
+       u64 gen = btrfs_super_generation(&root->fs_info->super_copy);
+       u64 objectid = search_objectid;
+       u32 size = btrfs_super_nodesize(&root->fs_info->super_copy);
+       u8 level = root->fs_info->super_copy.root_level;
+       size_t block_off = 0;
+
+       while (block_off < iobuf_size) {
+               void *block = iobuf + block_off;
+               struct btrfs_header *header = block;
+               u64 h_byte, h_level, h_gen, h_owner;
+
+//             printf("searching %Lu\n", offset + block_off);
+               h_byte = le64_to_cpu(header->bytenr);
+               h_owner = le64_to_cpu(header->owner);
+               h_level = header->level;
+               h_gen = le64_to_cpu(header->generation);
+
+               if (h_owner != objectid)
+                       goto next;
+               if (h_byte != (offset + block_off))
+                       goto next;
+               if (h_level != level)
+                       goto next;
+               if (csum_block(block, size)) {
+                       fprintf(stderr, "Well block %Lu seems good, "
+                               "but the csum doesn't match\n",
+                               h_byte);
+                       goto next;
+               }
+               if (h_gen != gen) {
+                       fprintf(stderr, "Well block %Lu seems great, "
+                               "but generation doesn't match, "
+                               "have=%Lu, want=%Lu\n", h_byte, h_gen,
+                               gen);
+                       goto next;
+               }
+               printf("Found tree root at %Lu\n", h_byte);
+               return 0;
+next:
+               block_off += size;
+       }
+
+       return 1;
+}
+
+static int read_physical(struct btrfs_root *root, int fd, u64 offset,
+                        u64 bytenr, u64 len)
+{
+       char *iobuf = malloc(len);
+       ssize_t done;
+       size_t total_read = 0;
+       int ret = 1;
+
+       if (!iobuf) {
+               fprintf(stderr, "No memory\n");
+               return -1;
+       }
+
+       while (total_read < len) {
+               done = pread64(fd, iobuf + total_read, len - total_read,
+                              bytenr + total_read);
+               if (done < 0) {
+                       fprintf(stderr, "Failed to read: %s\n",
+                               strerror(errno));
+                       ret = -1;
+                       goto out;
+               }
+               total_read += done;
+       }
+
+       ret = search_iobuf(root, iobuf, total_read, offset);
+out:
+       free(iobuf);
+       return ret;
+}
+
+static int find_root(struct btrfs_root *root)
+{
+       struct btrfs_multi_bio *multi = NULL;
+       struct btrfs_device *device;
+       u64 metadata_offset = 0, metadata_size = 0;
+       off_t offset = 0;
+       off_t bytenr;
+       int fd;
+       int err;
+       int ret = 1;
+
+       printf("Super think's the tree root is at %Lu, chunk root %Lu\n",
+              btrfs_super_root(&root->fs_info->super_copy),
+              btrfs_super_chunk_root(&root->fs_info->super_copy));
+
+       err = btrfs_next_metadata(&root->fs_info->mapping_tree,
+                                 &metadata_offset, &metadata_size);
+       if (err)
+               return ret;
+
+       offset = metadata_offset;
+       while (1) {
+               u64 map_length = 4096;
+               u64 type;
+
+               if (offset >
+                   btrfs_super_total_bytes(&root->fs_info->super_copy)) {
+                       printf("Went past the fs size, exiting");
+                       break;
+               }
+               if (offset >= (metadata_offset + metadata_size)) {
+                       err = btrfs_next_metadata(&root->fs_info->mapping_tree,
+                                                 &metadata_offset,
+                                                 &metadata_size);
+                       if (err) {
+                               printf("No more metdata to scan, exiting\n");
+                               break;
+                       }
+                       offset = metadata_offset;
+               }
+               err = __btrfs_map_block(&root->fs_info->mapping_tree, READ,
+                                     offset, &map_length, &type, &multi, 0);
+               if (err) {
+                       offset += map_length;
+                       continue;
+               }
+
+               if (!(type & BTRFS_BLOCK_GROUP_METADATA)) {
+                       offset += map_length;
+                       continue;
+               }
+
+               device = multi->stripes[0].dev;
+               fd = device->fd;
+               bytenr = multi->stripes[0].physical;
+               kfree(multi);
+
+               err = read_physical(root, fd, offset, bytenr, map_length);
+               if (!err) {
+                       ret = 0;
+                       break;
+               } else if (err < 0) {
+                       ret = err;
+                       break;
+               }
+               offset += map_length;
+       }
+       return ret;
+}
+
+int main(int argc, char **argv)
+{
+       struct btrfs_root *root;
+       int dev_fd;
+       int opt;
+       int ret;
+
+       while ((opt = getopt(argc, argv, "o:")) != -1) {
+               switch(opt) {
+                       case 'o':
+                               errno = 0;
+                               search_objectid = (u64)strtoll(optarg, NULL,
+                                                              10);
+                               if (errno) {
+                                       fprintf(stderr, "Error parsing "
+                                               "objectid\n");
+                                       exit(1);
+                               }
+                               break;
+                       default:
+                               usage();
+                               exit(1);
+               }
+       }
+
+       if (optind >= argc) {
+               usage();
+               exit(1);
+       }
+
+       dev_fd = open(argv[optind], O_RDONLY);
+       if (dev_fd < 0) {
+               fprintf(stderr, "Failed to open device %s\n", argv[optind]);
+               exit(1);
+       }
+
+       root = open_ctree_broken(dev_fd, argv[optind]);
+       close(dev_fd);
+       if (!root)
+               exit(1);
+
+       csum_size = btrfs_super_csum_size(&root->fs_info->super_copy);
+       ret = find_root(root);
+       close_ctree(root);
+       return ret;
+}
diff --git a/find-root.c b/find-root.c
deleted file mode 100644
index 2fb40e5..0000000
--- a/find-root.c
+++ /dev/null
@@ -1,454 +0,0 @@
-/*
- * Copyright (C) 2011 Red Hat.  All rights reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License v2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 021110-1307, USA.
- */
-
-#define _XOPEN_SOURCE 500
-#define _GNU_SOURCE 1
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/stat.h>
-#include <zlib.h>
-#include "kerncompat.h"
-#include "ctree.h"
-#include "disk-io.h"
-#include "print-tree.h"
-#include "transaction.h"
-#include "list.h"
-#include "version.h"
-#include "volumes.h"
-#include "utils.h"
-#include "crc32c.h"
-
-static u16 csum_size = 0;
-static u64 search_objectid = BTRFS_ROOT_TREE_OBJECTID;
-
-static void usage()
-{
-       fprintf(stderr, "Usage: find-roots [-o search_objectid] <device>\n");
-}
-
-int csum_block(void *buf, u32 len)
-{
-       char *result;
-       u32 crc = ~(u32)0;
-       int ret = 0;
-
-       result = malloc(csum_size * sizeof(char));
-       if (!result) {
-               fprintf(stderr, "No memory\n");
-               return 1;
-       }
-
-       len -= BTRFS_CSUM_SIZE;
-       crc = crc32c(crc, buf + BTRFS_CSUM_SIZE, len);
-       btrfs_csum_final(crc, result);
-
-       if (memcmp(buf, result, csum_size))
-               ret = 1;
-       free(result);
-       return ret;
-}
-
-static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
-                       u32 stripesize, struct btrfs_root *root,
-                       struct btrfs_fs_info *fs_info, u64 objectid)
-{
-       root->node = NULL;
-       root->commit_root = NULL;
-       root->sectorsize = sectorsize;
-       root->nodesize = nodesize;
-       root->leafsize = leafsize;
-       root->stripesize = stripesize;
-       root->ref_cows = 0;
-       root->track_dirty = 0;
-
-       root->fs_info = fs_info;
-       root->objectid = objectid;
-       root->last_trans = 0;
-       root->highest_inode = 0;
-       root->last_inode_alloc = 0;
-
-       INIT_LIST_HEAD(&root->dirty_list);
-       memset(&root->root_key, 0, sizeof(root->root_key));
-       memset(&root->root_item, 0, sizeof(root->root_item));
-       root->root_key.objectid = objectid;
-       return 0;
-}
-
-static int close_all_devices(struct btrfs_fs_info *fs_info)
-{
-       struct list_head *list;
-       struct list_head *next;
-       struct btrfs_device *device;
-
-       return 0;
-
-       list = &fs_info->fs_devices->devices;
-       list_for_each(next, list) {
-               device = list_entry(next, struct btrfs_device, dev_list);
-               close(device->fd);
-       }
-       return 0;
-}
-
-static struct btrfs_root *open_ctree_broken(int fd, const char *device)
-{
-       u32 sectorsize;
-       u32 nodesize;
-       u32 leafsize;
-       u32 blocksize;
-       u32 stripesize;
-       u64 generation;
-       struct btrfs_root *tree_root = malloc(sizeof(struct btrfs_root));
-       struct btrfs_root *extent_root = malloc(sizeof(struct btrfs_root));
-       struct btrfs_root *chunk_root = malloc(sizeof(struct btrfs_root));
-       struct btrfs_root *dev_root = malloc(sizeof(struct btrfs_root));
-       struct btrfs_root *csum_root = malloc(sizeof(struct btrfs_root));
-       struct btrfs_fs_info *fs_info = malloc(sizeof(*fs_info));
-       int ret;
-       struct btrfs_super_block *disk_super;
-       struct btrfs_fs_devices *fs_devices = NULL;
-       u64 total_devs;
-       u64 features;
-
-       ret = btrfs_scan_one_device(fd, device, &fs_devices,
-                                   &total_devs, BTRFS_SUPER_INFO_OFFSET);
-
-       if (ret) {
-               fprintf(stderr, "No valid Btrfs found on %s\n", device);
-               goto out;
-       }
-
-       if (total_devs != 1) {
-               ret = btrfs_scan_for_fsid(fs_devices, total_devs, 1);
-               if (ret)
-                       goto out;
-       }
-
-       memset(fs_info, 0, sizeof(*fs_info));
-       fs_info->tree_root = tree_root;
-       fs_info->extent_root = extent_root;
-       fs_info->chunk_root = chunk_root;
-       fs_info->dev_root = dev_root;
-       fs_info->csum_root = csum_root;
-
-       fs_info->readonly = 1;
-
-       extent_io_tree_init(&fs_info->extent_cache);
-       extent_io_tree_init(&fs_info->free_space_cache);
-       extent_io_tree_init(&fs_info->block_group_cache);
-       extent_io_tree_init(&fs_info->pinned_extents);
-       extent_io_tree_init(&fs_info->pending_del);
-       extent_io_tree_init(&fs_info->extent_ins);
-       cache_tree_init(&fs_info->fs_root_cache);
-
-       cache_tree_init(&fs_info->mapping_tree.cache_tree);
-
-       mutex_init(&fs_info->fs_mutex);
-       fs_info->fs_devices = fs_devices;
-       INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
-       INIT_LIST_HEAD(&fs_info->space_info);
-
-       __setup_root(4096, 4096, 4096, 4096, tree_root,
-                    fs_info, BTRFS_ROOT_TREE_OBJECTID);
-
-       ret = btrfs_open_devices(fs_devices, O_RDONLY);
-       if (ret)
-               goto out_cleanup;
-
-       fs_info->super_bytenr = BTRFS_SUPER_INFO_OFFSET;
-       disk_super = &fs_info->super_copy;
-       ret = btrfs_read_dev_super(fs_devices->latest_bdev,
-                                  disk_super, BTRFS_SUPER_INFO_OFFSET);
-       if (ret) {
-               printk("No valid btrfs found\n");
-               goto out_devices;
-       }
-
-       memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
-
-
-       features = btrfs_super_incompat_flags(disk_super) &
-                  ~BTRFS_FEATURE_INCOMPAT_SUPP;
-       if (features) {
-               printk("couldn't open because of unsupported "
-                      "option features (%Lx).\n", features);
-               goto out_devices;
-       }
-
-       features = btrfs_super_incompat_flags(disk_super);
-       if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
-               features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
-               btrfs_set_super_incompat_flags(disk_super, features);
-       }
-
-       nodesize = btrfs_super_nodesize(disk_super);
-       leafsize = btrfs_super_leafsize(disk_super);
-       sectorsize = btrfs_super_sectorsize(disk_super);
-       stripesize = btrfs_super_stripesize(disk_super);
-       tree_root->nodesize = nodesize;
-       tree_root->leafsize = leafsize;
-       tree_root->sectorsize = sectorsize;
-       tree_root->stripesize = stripesize;
-
-       ret = btrfs_read_sys_array(tree_root);
-       if (ret)
-               goto out_devices;
-       blocksize = btrfs_level_size(tree_root,
-                                    btrfs_super_chunk_root_level(disk_super));
-       generation = btrfs_super_chunk_root_generation(disk_super);
-
-       __setup_root(nodesize, leafsize, sectorsize, stripesize,
-                    chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
-
-       chunk_root->node = read_tree_block(chunk_root,
-                                          btrfs_super_chunk_root(disk_super),
-                                          blocksize, generation);
-       if (!chunk_root->node) {
-               printk("Couldn't read chunk root\n");
-               goto out_devices;
-       }
-
-       read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
-                (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
-                BTRFS_UUID_SIZE);
-
-       if (!(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_METADUMP)) {
-               ret = btrfs_read_chunk_tree(chunk_root);
-               if (ret)
-                       goto out_chunk;
-       }
-
-       return fs_info->chunk_root;
-out_chunk:
-       free_extent_buffer(fs_info->chunk_root->node);
-out_devices:
-       close_all_devices(fs_info);
-out_cleanup:
-       extent_io_tree_cleanup(&fs_info->extent_cache);
-       extent_io_tree_cleanup(&fs_info->free_space_cache);
-       extent_io_tree_cleanup(&fs_info->block_group_cache);
-       extent_io_tree_cleanup(&fs_info->pinned_extents);
-       extent_io_tree_cleanup(&fs_info->pending_del);
-       extent_io_tree_cleanup(&fs_info->extent_ins);
-out:
-       free(tree_root);
-       free(extent_root);
-       free(chunk_root);
-       free(dev_root);
-       free(csum_root);
-       free(fs_info);
-       return NULL;
-}
-
-static int search_iobuf(struct btrfs_root *root, void *iobuf,
-                       size_t iobuf_size, off_t offset)
-{
-       u64 gen = btrfs_super_generation(&root->fs_info->super_copy);
-       u64 objectid = search_objectid;
-       u32 size = btrfs_super_nodesize(&root->fs_info->super_copy);
-       u8 level = root->fs_info->super_copy.root_level;
-       size_t block_off = 0;
-
-       while (block_off < iobuf_size) {
-               void *block = iobuf + block_off;
-               struct btrfs_header *header = block;
-               u64 h_byte, h_level, h_gen, h_owner;
-
-//             printf("searching %Lu\n", offset + block_off);
-               h_byte = le64_to_cpu(header->bytenr);
-               h_owner = le64_to_cpu(header->owner);
-               h_level = header->level;
-               h_gen = le64_to_cpu(header->generation);
-
-               if (h_owner != objectid)
-                       goto next;
-               if (h_byte != (offset + block_off))
-                       goto next;
-               if (h_level != level)
-                       goto next;
-               if (csum_block(block, size)) {
-                       fprintf(stderr, "Well block %Lu seems good, "
-                               "but the csum doesn't match\n",
-                               h_byte);
-                       goto next;
-               }
-               if (h_gen != gen) {
-                       fprintf(stderr, "Well block %Lu seems great, "
-                               "but generation doesn't match, "
-                               "have=%Lu, want=%Lu\n", h_byte, h_gen,
-                               gen);
-                       goto next;
-               }
-               printf("Found tree root at %Lu\n", h_byte);
-               return 0;
-next:
-               block_off += size;
-       }
-
-       return 1;
-}
-
-static int read_physical(struct btrfs_root *root, int fd, u64 offset,
-                        u64 bytenr, u64 len)
-{
-       char *iobuf = malloc(len);
-       ssize_t done;
-       size_t total_read = 0;
-       int ret = 1;
-
-       if (!iobuf) {
-               fprintf(stderr, "No memory\n");
-               return -1;
-       }
-
-       while (total_read < len) {
-               done = pread64(fd, iobuf + total_read, len - total_read,
-                              bytenr + total_read);
-               if (done < 0) {
-                       fprintf(stderr, "Failed to read: %s\n",
-                               strerror(errno));
-                       ret = -1;
-                       goto out;
-               }
-               total_read += done;
-       }
-
-       ret = search_iobuf(root, iobuf, total_read, offset);
-out:
-       free(iobuf);
-       return ret;
-}
-
-static int find_root(struct btrfs_root *root)
-{
-       struct btrfs_multi_bio *multi = NULL;
-       struct btrfs_device *device;
-       u64 metadata_offset = 0, metadata_size = 0;
-       off_t offset = 0;
-       off_t bytenr;
-       int fd;
-       int err;
-       int ret = 1;
-
-       printf("Super think's the tree root is at %Lu, chunk root %Lu\n",
-              btrfs_super_root(&root->fs_info->super_copy),
-              btrfs_super_chunk_root(&root->fs_info->super_copy));
-
-       err = btrfs_next_metadata(&root->fs_info->mapping_tree,
-                                 &metadata_offset, &metadata_size);
-       if (err)
-               return ret;
-
-       offset = metadata_offset;
-       while (1) {
-               u64 map_length = 4096;
-               u64 type;
-
-               if (offset >
-                   btrfs_super_total_bytes(&root->fs_info->super_copy)) {
-                       printf("Went past the fs size, exiting");
-                       break;
-               }
-               if (offset >= (metadata_offset + metadata_size)) {
-                       err = btrfs_next_metadata(&root->fs_info->mapping_tree,
-                                                 &metadata_offset,
-                                                 &metadata_size);
-                       if (err) {
-                               printf("No more metdata to scan, exiting\n");
-                               break;
-                       }
-                       offset = metadata_offset;
-               }
-               err = __btrfs_map_block(&root->fs_info->mapping_tree, READ,
-                                     offset, &map_length, &type, &multi, 0);
-               if (err) {
-                       offset += map_length;
-                       continue;
-               }
-
-               if (!(type & BTRFS_BLOCK_GROUP_METADATA)) {
-                       offset += map_length;
-                       continue;
-               }
-
-               device = multi->stripes[0].dev;
-               fd = device->fd;
-               bytenr = multi->stripes[0].physical;
-               kfree(multi);
-
-               err = read_physical(root, fd, offset, bytenr, map_length);
-               if (!err) {
-                       ret = 0;
-                       break;
-               } else if (err < 0) {
-                       ret = err;
-                       break;
-               }
-               offset += map_length;
-       }
-       return ret;
-}
-
-int main(int argc, char **argv)
-{
-       struct btrfs_root *root;
-       int dev_fd;
-       int opt;
-       int ret;
-
-       while ((opt = getopt(argc, argv, "o:")) != -1) {
-               switch(opt) {
-                       case 'o':
-                               errno = 0;
-                               search_objectid = (u64)strtoll(optarg, NULL,
-                                                              10);
-                               if (errno) {
-                                       fprintf(stderr, "Error parsing "
-                                               "objectid\n");
-                                       exit(1);
-                               }
-                               break;
-                       default:
-                               usage();
-                               exit(1);
-               }
-       }
-
-       if (optind >= argc) {
-               usage();
-               exit(1);
-       }
-
-       dev_fd = open(argv[optind], O_RDONLY);
-       if (dev_fd < 0) {
-               fprintf(stderr, "Failed to open device %s\n", argv[optind]);
-               exit(1);
-       }
-
-       root = open_ctree_broken(dev_fd, argv[optind]);
-       close(dev_fd);
-       if (!root)
-               exit(1);
-
-       csum_size = btrfs_super_csum_size(&root->fs_info->super_copy);
-       ret = find_root(root);
-       close_ctree(root);
-       return ret;
-}
-- 
1.7.5.4
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