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-rw-r--r--find-root.c434
1 files changed, 0 insertions, 434 deletions
diff --git a/find-root.c b/find-root.c
deleted file mode 100644
index 810d8358..00000000
--- a/find-root.c
+++ /dev/null
@@ -1,434 +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 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->super_copy = calloc(1, BTRFS_SUPER_INFO_SIZE);
- 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, NULL);
- if (err) {
- offset += map_length;
- continue;
- }
-
- if (!(type & BTRFS_BLOCK_GROUP_METADATA)) {
- offset += map_length;
- kfree(multi);
- 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) {
- fprintf(stderr, "Open ctree failed\n");
- exit(1);
- }
-
- csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
- ret = find_root(root);
- close_ctree(root);
- return ret;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 13:24:01 +0000