#include <fcntl.h>
#include <sys/stat.h>
#include <zlib.h>
+#include <getopt.h>
+
#include "kerncompat.h"
#include "ctree.h"
#include "disk-io.h"
#include "volumes.h"
#include "utils.h"
#include "crc32c.h"
+#include "extent-cache.h"
+#include "find-root.h"
+#include "help.h"
-static u16 csum_size = 0;
-static u64 search_objectid = BTRFS_ROOT_TREE_OBJECTID;
-static u64 search_generation = 0;
-static unsigned long search_level = 0;
-
-static void usage(void)
+static void find_root_usage(void)
{
- fprintf(stderr, "Usage: find-roots [-o search_objectid] "
+ fprintf(stderr, "Usage: find-roots [-a] [-o search_objectid] "
"[ -g search_generation ] [ -l search_level ] <device>\n");
}
-static 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 struct btrfs_root *open_ctree_broken(int fd, const char *device)
-{
- struct btrfs_fs_info *fs_info;
- struct btrfs_super_block *disk_super;
- struct btrfs_fs_devices *fs_devices = NULL;
- struct extent_buffer *eb;
- int ret;
-
- fs_info = btrfs_new_fs_info(0, BTRFS_SUPER_INFO_OFFSET);
- if (!fs_info) {
- fprintf(stderr, "Failed to allocate memory for fs_info\n");
- return NULL;
- }
-
- ret = btrfs_scan_fs_devices(fd, device, &fs_devices, 0, 1, 0);
- if (ret)
- goto out;
-
- fs_info->fs_devices = fs_devices;
-
- ret = btrfs_open_devices(fs_devices, O_RDONLY);
- if (ret)
- goto out_devices;
-
- disk_super = fs_info->super_copy;
- ret = btrfs_read_dev_super(fs_devices->latest_bdev,
- disk_super, fs_info->super_bytenr, 1);
- if (ret) {
- printk("No valid btrfs found\n");
- goto out_devices;
- }
-
- memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
-
- ret = btrfs_check_fs_compatibility(disk_super, 0);
- if (ret)
- goto out_devices;
-
- ret = btrfs_setup_chunk_tree_and_device_map(fs_info);
- if (ret)
- goto out_chunk;
-
- eb = fs_info->chunk_root->node;
- read_extent_buffer(eb, fs_info->chunk_tree_uuid,
- btrfs_header_chunk_tree_uuid(eb), BTRFS_UUID_SIZE);
-
- return fs_info->chunk_root;
-out_chunk:
- free_extent_buffer(fs_info->chunk_root->node);
- btrfs_cleanup_all_caches(fs_info);
-out_devices:
- btrfs_close_devices(fs_info->fs_devices);
-out:
- btrfs_free_fs_info(fs_info);
- return NULL;
-}
-
-static int search_iobuf(struct btrfs_root *root, void *iobuf,
- size_t iobuf_size, off_t offset)
-{
- u64 gen = search_generation;
- u64 objectid = search_objectid;
- u32 size = btrfs_super_nodesize(root->fs_info->super_copy);
- u8 level = search_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 = btrfs_stack_header_bytenr(header);
- h_owner = btrfs_stack_header_owner(header);
- h_level = header->level;
- h_gen = btrfs_stack_header_generation(header);
-
- if (h_owner != objectid)
- goto next;
- if (h_byte != (offset + block_off))
- goto next;
- if (h_level < level)
- goto next;
- level = h_level;
- 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 level %Lu\n", h_byte,
- h_gen, gen, h_level);
- goto next;
- }
- printf("Found tree root at %Lu gen %Lu level %Lu\n", h_byte,
- h_gen, h_level);
- 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;
-}
-
/*
* Get reliable generation and level for given root.
*
case BTRFS_CHUNK_TREE_OBJECTID:
level = btrfs_super_chunk_root_level(super);
gen = btrfs_super_chunk_root_generation(super);
- printf("Search for chunk root is not supported yet\n");
break;
case BTRFS_TREE_LOG_OBJECTID:
level = btrfs_super_log_root_level(super);
}
}
+static void print_one_result(struct cache_extent *tree_block,
+ u8 level, u64 generation,
+ struct btrfs_find_root_filter *filter)
+{
+ int unsure = 0;
+
+ if (filter->match_gen == (u64)-1 || filter->match_level == (u8)-1)
+ unsure = 1;
+ printf("Well block %llu(gen: %llu level: %u) seems good, ",
+ tree_block->start, generation, level);
+ if (unsure)
+ printf("but we are unsure about the correct generation/level\n");
+ else if (level == filter->match_level &&
+ generation == filter->match_gen)
+ printf("and it matches superblock\n");
+ else
+ printf("but generation/level doesn't match, want gen: %llu level: %u\n",
+ filter->match_gen, filter->match_level);
+}
+
+static void print_find_root_result(struct cache_tree *result,
+ struct btrfs_find_root_filter *filter)
+{
+ struct btrfs_find_root_gen_cache *gen_cache;
+ struct cache_extent *cache;
+ struct cache_extent *tree_block;
+ u64 generation = 0;
+ u8 level = 0;
+
+ for (cache = last_cache_extent(result);
+ cache; cache = prev_cache_extent(cache)) {
+ gen_cache = container_of(cache,
+ struct btrfs_find_root_gen_cache, cache);
+ level = gen_cache->highest_level;
+ generation = cache->start;
+ /* For exact found one, skip it as it's output before */
+ if (level == filter->match_level &&
+ generation == filter->match_gen &&
+ !filter->search_all)
+ continue;
+ for (tree_block = last_cache_extent(&gen_cache->eb_tree);
+ tree_block; tree_block = prev_cache_extent(tree_block))
+ print_one_result(tree_block, level, generation, filter);
+ }
+}
+
int main(int argc, char **argv)
{
- struct btrfs_root *root;
- int opt;
+ struct btrfs_fs_info *fs_info;
+ struct btrfs_find_root_filter filter = {0};
+ struct cache_tree result;
+ struct cache_extent *found;
int ret;
- while ((opt = getopt(argc, argv, "l:o:g:")) != -1) {
- switch(opt) {
- case 'o':
- search_objectid = arg_strtou64(optarg);
- break;
- case 'g':
- search_generation = arg_strtou64(optarg);
- break;
- case 'l':
- search_level = arg_strtou64(optarg);
- break;
- default:
- usage();
- exit(1);
+ /* Default to search root tree */
+ filter.objectid = BTRFS_ROOT_TREE_OBJECTID;
+ filter.match_gen = (u64)-1;
+ filter.match_level = (u8)-1;
+ while (1) {
+ static const struct option long_options[] = {
+ { "help", no_argument, NULL, GETOPT_VAL_HELP},
+ { NULL, 0, NULL, 0 }
+ };
+ int c = getopt_long(argc, argv, "al:o:g:", long_options, NULL);
+
+ if (c < 0)
+ break;
+
+ switch (c) {
+ case 'a':
+ filter.search_all = 1;
+ break;
+ case 'o':
+ filter.objectid = arg_strtou64(optarg);
+ break;
+ case 'g':
+ filter.generation = arg_strtou64(optarg);
+ break;
+ case 'l':
+ filter.level = arg_strtou64(optarg);
+ break;
+ case GETOPT_VAL_HELP:
+ default:
+ find_root_usage();
+ exit(c != GETOPT_VAL_HELP);
}
}
set_argv0(argv);
- argc = argc - optind;
- if (check_argc_min(argc, 1)) {
- usage();
+ if (check_argc_min(argc - optind, 1)) {
+ find_root_usage();
exit(1);
}
- root = open_ctree(argv[optind], 0, OPEN_CTREE_CHUNK_ROOT_ONLY);
- if (!root) {
- fprintf(stderr, "Open ctree failed\n");
+ fs_info = open_ctree_fs_info(argv[optind], 0, 0, 0,
+ OPEN_CTREE_CHUNK_ROOT_ONLY |
+ OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
+ if (!fs_info) {
+ error("open ctree failed");
exit(1);
}
-
- if (search_generation == 0)
- get_root_gen_and_level(search_objectid, root->fs_info,
- &search_generation, NULL);
-
- csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
- ret = find_root(root);
- close_ctree(root);
+ cache_tree_init(&result);
+
+ get_root_gen_and_level(filter.objectid, fs_info,
+ &filter.match_gen, &filter.match_level);
+ ret = btrfs_find_root_search(fs_info, &filter, &result, &found);
+ if (ret < 0) {
+ fprintf(stderr, "Fail to search the tree root: %s\n",
+ strerror(-ret));
+ goto out;
+ }
+ if (ret > 0) {
+ printf("Found tree root at %llu gen %llu level %u\n",
+ found->start, filter.match_gen, filter.match_level);
+ ret = 0;
+ }
+ print_find_root_result(&result, &filter);
+out:
+ btrfs_find_root_free(&result);
+ close_ctree_fs_info(fs_info);
+ btrfs_close_all_devices();
return ret;
}
projects / platform / upstream / btrfs-progs.git / blobdiff