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btrfs-progs/cmds-restore.c

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/*
* 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.
*/
#include "kerncompat.h"
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <lzo/lzoconf.h>
#include <lzo/lzo1x.h>
#include <zlib.h>
#include <regex.h>
#include <getopt.h>
#include <sys/types.h>
#include <sys/xattr.h>
#include "ctree.h"
#include "disk-io.h"
#include "print-tree.h"
#include "transaction.h"
#include "list.h"
#include "volumes.h"
#include "utils.h"
#include "commands.h"
static char fs_name[PATH_MAX];
static char path_name[PATH_MAX];
static char symlink_target[PATH_MAX];
static int get_snaps = 0;
static int verbose = 0;
static int restore_metadata = 0;
static int restore_symlinks = 0;
static int ignore_errors = 0;
static int overwrite = 0;
static int get_xattrs = 0;
static int dry_run = 0;
#define LZO_LEN 4
#define lzo1x_worst_compress(x) ((x) + ((x) / 16) + 64 + 3)
static int decompress_zlib(char *inbuf, char *outbuf, u64 compress_len,
u64 decompress_len)
{
z_stream strm;
int ret;
memset(&strm, 0, sizeof(strm));
ret = inflateInit(&strm);
if (ret != Z_OK) {
error("zlib init returned %d", ret);
return -1;
}
strm.avail_in = compress_len;
strm.next_in = (unsigned char *)inbuf;
strm.avail_out = decompress_len;
strm.next_out = (unsigned char *)outbuf;
ret = inflate(&strm, Z_NO_FLUSH);
if (ret != Z_STREAM_END) {
(void)inflateEnd(&strm);
error("zlib inflate failed: %d", ret);
return -1;
}
(void)inflateEnd(&strm);
return 0;
}
static inline size_t read_compress_length(unsigned char *buf)
{
__le32 dlen;
memcpy(&dlen, buf, LZO_LEN);
return le32_to_cpu(dlen);
}
static int decompress_lzo(struct btrfs_root *root, unsigned char *inbuf,
char *outbuf, u64 compress_len, u64 *decompress_len)
{
size_t new_len;
size_t in_len;
size_t out_len = 0;
size_t tot_len;
size_t tot_in;
int ret;
ret = lzo_init();
if (ret != LZO_E_OK) {
error("lzo init returned %d", ret);
return -1;
}
tot_len = read_compress_length(inbuf);
inbuf += LZO_LEN;
tot_in = LZO_LEN;
while (tot_in < tot_len) {
size_t mod_page;
size_t rem_page;
in_len = read_compress_length(inbuf);
if ((tot_in + LZO_LEN + in_len) > tot_len) {
error("bad compress length %lu",
(unsigned long)in_len);
return -1;
}
inbuf += LZO_LEN;
tot_in += LZO_LEN;
new_len = lzo1x_worst_compress(root->sectorsize);
ret = lzo1x_decompress_safe((const unsigned char *)inbuf, in_len,
(unsigned char *)outbuf,
(void *)&new_len, NULL);
if (ret != LZO_E_OK) {
error("lzo decompress failed: %d", ret);
return -1;
}
out_len += new_len;
outbuf += new_len;
inbuf += in_len;
tot_in += in_len;
/*
* If the 4 byte header does not fit to the rest of the page we
* have to move to the next one, unless we read some garbage
*/
mod_page = tot_in % root->sectorsize;
rem_page = root->sectorsize - mod_page;
if (rem_page < LZO_LEN) {
inbuf += rem_page;
tot_in += rem_page;
}
}
*decompress_len = out_len;
return 0;
}
static int decompress(struct btrfs_root *root, char *inbuf, char *outbuf,
u64 compress_len, u64 *decompress_len, int compress)
{
switch (compress) {
case BTRFS_COMPRESS_ZLIB:
return decompress_zlib(inbuf, outbuf, compress_len,
*decompress_len);
case BTRFS_COMPRESS_LZO:
return decompress_lzo(root, (unsigned char *)inbuf, outbuf,
compress_len, decompress_len);
default:
break;
}
error("invalid compression type: %d", compress);
return -1;
}
static int next_leaf(struct btrfs_root *root, struct btrfs_path *path)
{
int slot;
int level = 1;
int offset = 1;
struct extent_buffer *c;
struct extent_buffer *next = NULL;
again:
for (; level < BTRFS_MAX_LEVEL; level++) {
if (path->nodes[level])
break;
}
if (level >= BTRFS_MAX_LEVEL)
return 1;
slot = path->slots[level] + 1;
while(level < BTRFS_MAX_LEVEL) {
if (!path->nodes[level])
return 1;
slot = path->slots[level] + offset;
c = path->nodes[level];
if (slot >= btrfs_header_nritems(c)) {
level++;
if (level == BTRFS_MAX_LEVEL)
return 1;
offset = 1;
continue;
}
if (path->reada)
reada_for_search(root, path, level, slot, 0);
next = read_node_slot(root, c, slot);
if (extent_buffer_uptodate(next))
break;
offset++;
}
path->slots[level] = slot;
while(1) {
level--;
c = path->nodes[level];
free_extent_buffer(c);
path->nodes[level] = next;
path->slots[level] = 0;
if (!level)
break;
if (path->reada)
reada_for_search(root, path, level, 0, 0);
next = read_node_slot(root, next, 0);
if (!extent_buffer_uptodate(next))
goto again;
}
return 0;
}
static int copy_one_inline(struct btrfs_root *root, int fd,
struct btrfs_path *path, u64 pos)
{
struct extent_buffer *leaf = path->nodes[0];
struct btrfs_file_extent_item *fi;
char buf[4096];
char *outbuf;
u64 ram_size;
ssize_t done;
unsigned long ptr;
int ret;
int len;
int inline_item_len;
int compress;
fi = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_file_extent_item);
ptr = btrfs_file_extent_inline_start(fi);
len = btrfs_file_extent_inline_len(leaf, path->slots[0], fi);
inline_item_len = btrfs_file_extent_inline_item_len(leaf, btrfs_item_nr(path->slots[0]));
read_extent_buffer(leaf, buf, ptr, inline_item_len);
compress = btrfs_file_extent_compression(leaf, fi);
if (compress == BTRFS_COMPRESS_NONE) {
done = pwrite(fd, buf, len, pos);
if (done < len) {
fprintf(stderr, "Short inline write, wanted %d, did "
"%zd: %d\n", len, done, errno);
return -1;
}
return 0;
}
ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
outbuf = calloc(1, ram_size);
if (!outbuf) {
error("not enough memory");
return -ENOMEM;
}
ret = decompress(root, buf, outbuf, len, &ram_size, compress);
if (ret) {
free(outbuf);
return ret;
}
done = pwrite(fd, outbuf, ram_size, pos);
free(outbuf);
if (done < ram_size) {
fprintf(stderr, "Short compressed inline write, wanted %Lu, "
"did %zd: %d\n", ram_size, done, errno);
return -1;
}
return 0;
}
static int copy_one_extent(struct btrfs_root *root, int fd,
struct extent_buffer *leaf,
struct btrfs_file_extent_item *fi, u64 pos)
{
struct btrfs_multi_bio *multi = NULL;
struct btrfs_device *device;
char *inbuf, *outbuf = NULL;
ssize_t done, total = 0;
u64 bytenr;
u64 ram_size;
u64 disk_size;
u64 num_bytes;
u64 length;
u64 size_left;
u64 dev_bytenr;
u64 offset;
u64 count = 0;
int compress;
int ret;
int dev_fd;
int mirror_num = 1;
int num_copies;
compress = btrfs_file_extent_compression(leaf, fi);
bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
disk_size = btrfs_file_extent_disk_num_bytes(leaf, fi);
ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
offset = btrfs_file_extent_offset(leaf, fi);
num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
size_left = disk_size;
if (compress == BTRFS_COMPRESS_NONE)
bytenr += offset;
if (verbose && offset)
printf("offset is %Lu\n", offset);
/* we found a hole */
if (disk_size == 0)
return 0;
inbuf = malloc(size_left);
if (!inbuf) {
error("not enough memory\n");
return -ENOMEM;
}
if (compress != BTRFS_COMPRESS_NONE) {
outbuf = calloc(1, ram_size);
if (!outbuf) {
error("not enough memory");
free(inbuf);
return -ENOMEM;
}
}
again:
length = size_left;
ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
bytenr, &length, &multi, mirror_num, NULL);
if (ret) {
error("cannot map block logical %llu length %llu: %d",
(unsigned long long)bytenr,
(unsigned long long)length, ret);
goto out;
}
device = multi->stripes[0].dev;
dev_fd = device->fd;
device->total_ios++;
dev_bytenr = multi->stripes[0].physical;
free(multi);
if (size_left < length)
length = size_left;
done = pread(dev_fd, inbuf+count, length, dev_bytenr);
/* Need both checks, or we miss negative values due to u64 conversion */
if (done < 0 || done < length) {
num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
bytenr, length);
mirror_num++;
/* mirror_num is 1-indexed, so num_copies is a valid mirror. */
if (mirror_num > num_copies) {
ret = -1;
error("exhausted mirrors trying to read (%d > %d)",
mirror_num, num_copies);
goto out;
}
fprintf(stderr, "Trying another mirror\n");
goto again;
}
mirror_num = 1;
size_left -= length;
count += length;
bytenr += length;
if (size_left)
goto again;
if (compress == BTRFS_COMPRESS_NONE) {
while (total < num_bytes) {
done = pwrite(fd, inbuf+total, num_bytes-total,
pos+total);
if (done < 0) {
ret = -1;
error("cannot write data: %d %s", errno, strerror(errno));
goto out;
}
total += done;
}
ret = 0;
goto out;
}
ret = decompress(root, inbuf, outbuf, disk_size, &ram_size, compress);
if (ret) {
num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
bytenr, length);
mirror_num++;
if (mirror_num >= num_copies) {
ret = -1;
goto out;
}
fprintf(stderr, "Trying another mirror\n");
goto again;
}
while (total < num_bytes) {
done = pwrite(fd, outbuf + offset + total,
num_bytes - total,
pos + total);
if (done < 0) {
ret = -1;
goto out;
}
total += done;
}
out:
free(inbuf);
free(outbuf);
return ret;
}
enum loop_response {
LOOP_STOP,
LOOP_CONTINUE,
LOOP_DONTASK
};
static enum loop_response ask_to_continue(const char *file)
{
char buf[2];
char *ret;
printf("We seem to be looping a lot on %s, do you want to keep going "
"on ? (y/N/a): ", file);
again:
ret = fgets(buf, 2, stdin);
if (*ret == '\n' || tolower(*ret) == 'n')
return LOOP_STOP;
if (tolower(*ret) == 'a')
return LOOP_DONTASK;
if (tolower(*ret) != 'y') {
printf("Please enter one of 'y', 'n', or 'a': ");
goto again;
}
return LOOP_CONTINUE;
}
static int set_file_xattrs(struct btrfs_root *root, u64 inode,
int fd, const char *file_name)
{
struct btrfs_key key;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_dir_item *di;
u32 name_len = 0;
u32 data_len = 0;
u32 len = 0;
u32 cur, total_len;
char *name = NULL;
char *data = NULL;
int ret = 0;
key.objectid = inode;
key.type = BTRFS_XATTR_ITEM_KEY;
key.offset = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto out;
leaf = path->nodes[0];
while (1) {
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
do {
ret = next_leaf(root, path);
if (ret < 0) {
error("searching for extended attributes: %d\n",
ret);
goto out;
} else if (ret) {
/* No more leaves to search */
ret = 0;
goto out;
}
leaf = path->nodes[0];
} while (!leaf);
continue;
}
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (key.type != BTRFS_XATTR_ITEM_KEY || key.objectid != inode)
break;
cur = 0;
total_len = btrfs_item_size_nr(leaf, path->slots[0]);
di = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_dir_item);
while (cur < total_len) {
len = btrfs_dir_name_len(leaf, di);
if (len > name_len) {
free(name);
name = (char *) malloc(len + 1);
if (!name) {
ret = -ENOMEM;
goto out;
}
}
read_extent_buffer(leaf, name,
(unsigned long)(di + 1), len);
name[len] = '\0';
name_len = len;
len = btrfs_dir_data_len(leaf, di);
if (len > data_len) {
free(data);
data = (char *) malloc(len);
if (!data) {
ret = -ENOMEM;
goto out;
}
}
read_extent_buffer(leaf, data,
(unsigned long)(di + 1) + name_len,
len);
data_len = len;
if (fsetxattr(fd, name, data, data_len, 0))
error("setting extended attribute %s on file %s: %s",
name, file_name, strerror(errno));
len = sizeof(*di) + name_len + data_len;
cur += len;
di = (struct btrfs_dir_item *)((char *)di + len);
}
path->slots[0]++;
}
ret = 0;
out:
btrfs_free_path(path);
free(name);
free(data);
return ret;
}
static int copy_metadata(struct btrfs_root *root, int fd,
struct btrfs_key *key)
{
struct btrfs_path *path;
struct btrfs_inode_item *inode_item;
int ret;
path = btrfs_alloc_path();
if (!path) {
error("not enough memory");
return -ENOMEM;
}
ret = btrfs_lookup_inode(NULL, root, path, key, 0);
if (ret == 0) {
struct btrfs_timespec *bts;
struct timespec times[2];
inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_inode_item);
ret = fchown(fd, btrfs_inode_uid(path->nodes[0], inode_item),
btrfs_inode_gid(path->nodes[0], inode_item));
if (ret) {
error("failed to change owner: %s", strerror(errno));
goto out;
}
ret = fchmod(fd, btrfs_inode_mode(path->nodes[0], inode_item));
if (ret) {
error("failed to change mode: %s", strerror(errno));
goto out;
}
bts = btrfs_inode_atime(inode_item);
times[0].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
times[0].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
bts = btrfs_inode_mtime(inode_item);
times[1].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
times[1].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
ret = futimens(fd, times);
if (ret) {
error("failed to set times: %s", strerror(errno));
goto out;
}
}
out:
btrfs_free_path(path);
return ret;
}
static int copy_file(struct btrfs_root *root, int fd, struct btrfs_key *key,
const char *file)
{
struct extent_buffer *leaf;
struct btrfs_path *path;
struct btrfs_file_extent_item *fi;
struct btrfs_inode_item *inode_item;
struct btrfs_timespec *bts;
struct btrfs_key found_key;
int ret;
int extent_type;
int compression;
int loops = 0;
u64 found_size = 0;
struct timespec times[2];
int times_ok = 0;
path = btrfs_alloc_path();
if (!path) {
error("not enough memory");
return -ENOMEM;
}
ret = btrfs_lookup_inode(NULL, root, path, key, 0);
if (ret == 0) {
inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_inode_item);
found_size = btrfs_inode_size(path->nodes[0], inode_item);
if (restore_metadata) {
/*
* Change the ownership and mode now, set times when
* copyout is finished.
*/
ret = fchown(fd, btrfs_inode_uid(path->nodes[0], inode_item),
btrfs_inode_gid(path->nodes[0], inode_item));
if (ret && !ignore_errors)
goto out;
ret = fchmod(fd, btrfs_inode_mode(path->nodes[0], inode_item));
if (ret && !ignore_errors)
goto out;
bts = btrfs_inode_atime(inode_item);
times[0].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
times[0].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
bts = btrfs_inode_mtime(inode_item);
times[1].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
times[1].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
times_ok = 1;
}
}
btrfs_release_path(path);
key->offset = 0;
key->type = BTRFS_EXTENT_DATA_KEY;
ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
if (ret < 0) {
error("searching extent data returned %d", ret);
goto out;
}
leaf = path->nodes[0];
while (!leaf) {
ret = next_leaf(root, path);
if (ret < 0) {
error("cannot get next leaf: %d", ret);
goto out;
} else if (ret > 0) {
/* No more leaves to search */
ret = 0;
goto out;
}
leaf = path->nodes[0];
}
while (1) {
if (loops >= 0 && loops++ >= 1024) {
enum loop_response resp;
resp = ask_to_continue(file);
if (resp == LOOP_STOP)
break;
else if (resp == LOOP_CONTINUE)
loops = 0;
else if (resp == LOOP_DONTASK)
loops = -1;
}
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
do {
ret = next_leaf(root, path);
if (ret < 0) {
fprintf(stderr, "Error searching %d\n", ret);
goto out;
} else if (ret) {
/* No more leaves to search */
btrfs_free_path(path);
goto set_size;
}
leaf = path->nodes[0];
} while (!leaf);
continue;
}
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (found_key.objectid != key->objectid)
break;
if (found_key.type != key->type)
break;
fi = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_file_extent_item);
extent_type = btrfs_file_extent_type(leaf, fi);
compression = btrfs_file_extent_compression(leaf, fi);
if (compression >= BTRFS_COMPRESS_LAST) {
warning("compression type %d not supported",
compression);
ret = -1;
goto out;
}
if (extent_type == BTRFS_FILE_EXTENT_PREALLOC)
goto next;
if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
ret = copy_one_inline(root, fd, path, found_key.offset);
if (ret)
goto out;
} else if (extent_type == BTRFS_FILE_EXTENT_REG) {
ret = copy_one_extent(root, fd, leaf, fi,
found_key.offset);
if (ret)
goto out;
} else {
warning("weird extent type %d", extent_type);
}
next:
path->slots[0]++;
}
btrfs_free_path(path);
set_size:
if (found_size) {
ret = ftruncate(fd, (loff_t)found_size);
if (ret)
return ret;
}
if (get_xattrs) {
ret = set_file_xattrs(root, key->objectid, fd, file);
if (ret)
return ret;
}
if (restore_metadata && times_ok) {
ret = futimens(fd, times);
if (ret)
return ret;
}
return 0;
out:
btrfs_free_path(path);
return ret;
}
/*
* returns:
* 0 if the file exists and should be skipped.
* 1 if the file does NOT exist
* 2 if the file exists but is OK to overwrite
*/
static int overwrite_ok(const char * path)
{
static int warn = 0;
struct stat st;
int ret;
/* don't be fooled by symlinks */
ret = fstatat(-1, path_name, &st, AT_SYMLINK_NOFOLLOW);
if (!ret) {
if (overwrite)
return 2;
if (verbose || !warn)
printf("Skipping existing file"
" %s\n", path);
if (!warn)
printf("If you wish to overwrite use -o\n");
warn = 1;
return 0;
}
return 1;
}
static int copy_symlink(struct btrfs_root *root, struct btrfs_key *key,
const char *file)
{
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_file_extent_item *extent_item;
struct btrfs_inode_item *inode_item;
u32 len;
u32 name_offset;
int ret;
struct btrfs_timespec *bts;
struct timespec times[2];
ret = overwrite_ok(path_name);
if (ret == 0)
return 0; /* skip this file */
/* symlink() can't overwrite, so unlink first */
if (ret == 2) {
ret = unlink(path_name);
if (ret) {
fprintf(stderr, "failed to unlink '%s' for overwrite\n",
path_name);
return ret;
}
}
key->type = BTRFS_EXTENT_DATA_KEY;
key->offset = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
if (ret < 0)
goto out;
leaf = path->nodes[0];
if (!leaf) {
fprintf(stderr, "Error getting leaf for symlink '%s'\n", file);
ret = -1;
goto out;
}
extent_item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_file_extent_item);
len = btrfs_file_extent_inline_item_len(leaf,
btrfs_item_nr(path->slots[0]));
if (len >= PATH_MAX) {
fprintf(stderr, "Symlink '%s' target length %d is longer than PATH_MAX\n",
fs_name, len);
ret = -1;
goto out;
}
name_offset = (unsigned long) extent_item
+ offsetof(struct btrfs_file_extent_item, disk_bytenr);
read_extent_buffer(leaf, symlink_target, name_offset, len);
symlink_target[len] = 0;
if (!dry_run) {
ret = symlink(symlink_target, path_name);
if (ret < 0) {
fprintf(stderr, "Failed to restore symlink '%s': %s\n",
path_name, strerror(errno));
goto out;
}
}
printf("SYMLINK: '%s' => '%s'\n", path_name, symlink_target);
ret = 0;
if (!restore_metadata)
goto out;
/*
* Symlink metadata operates differently than files/directories, so do
* our own work here.
*/
key->type = BTRFS_INODE_ITEM_KEY;
key->offset = 0;
btrfs_release_path(path);
ret = btrfs_lookup_inode(NULL, root, path, key, 0);
if (ret) {
fprintf(stderr, "Failed to lookup inode for '%s'\n", file);
goto out;
}
inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_inode_item);
ret = fchownat(-1, file, btrfs_inode_uid(path->nodes[0], inode_item),
btrfs_inode_gid(path->nodes[0], inode_item),
AT_SYMLINK_NOFOLLOW);
if (ret) {
fprintf(stderr, "Failed to change owner: %s\n",
strerror(errno));
goto out;
}
bts = btrfs_inode_atime(inode_item);
times[0].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
times[0].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
bts = btrfs_inode_mtime(inode_item);
times[1].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
times[1].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
ret = utimensat(-1, file, times, AT_SYMLINK_NOFOLLOW);
if (ret)
fprintf(stderr, "Failed to set times: %s\n", strerror(errno));
out:
btrfs_free_path(path);
return ret;
}
static int search_dir(struct btrfs_root *root, struct btrfs_key *key,
const char *output_rootdir, const char *in_dir,
const regex_t *mreg)
{
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_dir_item *dir_item;
struct btrfs_key found_key, location;
char filename[BTRFS_NAME_LEN + 1];
unsigned long name_ptr;
int name_len;
int ret = 0;
int fd;
int loops = 0;
u8 type;
path = btrfs_alloc_path();
if (!path) {
fprintf(stderr, "Ran out of memory\n");
return -ENOMEM;
}
key->offset = 0;
key->type = BTRFS_DIR_INDEX_KEY;
ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
if (ret < 0) {
fprintf(stderr, "Error searching %d\n", ret);
goto out;
}
ret = 0;
leaf = path->nodes[0];
while (!leaf) {
if (verbose > 1)
printf("No leaf after search, looking for the next "
"leaf\n");
ret = next_leaf(root, path);
if (ret < 0) {
fprintf(stderr, "Error getting next leaf %d\n",
ret);
goto out;
} else if (ret > 0) {
/* No more leaves to search */
if (verbose)
printf("Reached the end of the tree looking "
"for the directory\n");
ret = 0;
goto out;
}
leaf = path->nodes[0];
}
while (leaf) {
if (loops++ >= 1024) {
printf("We have looped trying to restore files in %s "
"too many times to be making progress, "
"stopping\n", in_dir);
break;
}
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
do {
ret = next_leaf(root, path);
if (ret < 0) {
fprintf(stderr, "Error searching %d\n",
ret);
goto out;
} else if (ret > 0) {
/* No more leaves to search */
if (verbose)
printf("Reached the end of "
"the tree searching the"
" directory\n");
ret = 0;
goto out;
}
leaf = path->nodes[0];
} while (!leaf);
continue;
}
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (found_key.objectid != key->objectid) {
if (verbose > 1)
printf("Found objectid=%Lu, key=%Lu\n",
found_key.objectid, key->objectid);
break;
}
if (found_key.type != key->type) {
if (verbose > 1)
printf("Found type=%u, want=%u\n",
found_key.type, key->type);
break;
}
dir_item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_dir_item);
name_ptr = (unsigned long)(dir_item + 1);
name_len = btrfs_dir_name_len(leaf, dir_item);
read_extent_buffer(leaf, filename, name_ptr, name_len);
filename[name_len] = '\0';
type = btrfs_dir_type(leaf, dir_item);
btrfs_dir_item_key_to_cpu(leaf, dir_item, &location);
/* full path from root of btrfs being restored */
snprintf(fs_name, PATH_MAX, "%s/%s", in_dir, filename);
if (mreg && REG_NOMATCH == regexec(mreg, fs_name, 0, NULL, 0))
goto next;
/* full path from system root */
snprintf(path_name, PATH_MAX, "%s%s", output_rootdir, fs_name);
/*
* Restore directories, files, symlinks and metadata.
*/
if (type == BTRFS_FT_REG_FILE) {
if (!overwrite_ok(path_name))
goto next;
if (verbose)
printf("Restoring %s\n", path_name);
if (dry_run)
goto next;
fd = open(path_name, O_CREAT|O_WRONLY, 0644);
if (fd < 0) {
fprintf(stderr, "Error creating %s: %d\n",
path_name, errno);
if (ignore_errors)
goto next;
ret = -1;
goto out;
}
loops = 0;
ret = copy_file(root, fd, &location, path_name);
close(fd);
if (ret) {
fprintf(stderr, "Error copying data for %s\n",
path_name);
if (ignore_errors)
goto next;
goto out;
}
} else if (type == BTRFS_FT_DIR) {
struct btrfs_root *search_root = root;
char *dir = strdup(fs_name);
if (!dir) {
fprintf(stderr, "Ran out of memory\n");
ret = -ENOMEM;
goto out;
}
if (location.type == BTRFS_ROOT_ITEM_KEY) {
/*
* If we are a snapshot and this is the index
* object to ourselves just skip it.
*/
if (location.objectid ==
root->root_key.objectid) {
free(dir);
goto next;
}
location.offset = (u64)-1;
search_root = btrfs_read_fs_root(root->fs_info,
&location);
if (IS_ERR(search_root)) {
free(dir);
fprintf(stderr, "Error reading "
"subvolume %s: %lu\n",
path_name,
PTR_ERR(search_root));
if (ignore_errors)
goto next;
ret = PTR_ERR(search_root);
goto out;
}
/*
* A subvolume will have a key.offset of 0, a
* snapshot will have key.offset of a transid.
*/
if (search_root->root_key.offset != 0 &&
get_snaps == 0) {
free(dir);
printf("Skipping snapshot %s\n",
filename);
goto next;
}
location.objectid = BTRFS_FIRST_FREE_OBJECTID;
}
if (verbose)
printf("Restoring %s\n", path_name);
errno = 0;
if (dry_run)
ret = 0;
else
ret = mkdir(path_name, 0755);
if (ret && errno != EEXIST) {
free(dir);
fprintf(stderr, "Error mkdiring %s: %d\n",
path_name, errno);
if (ignore_errors)
goto next;
ret = -1;
goto out;
}
loops = 0;
ret = search_dir(search_root, &location,
output_rootdir, dir, mreg);
free(dir);
if (ret) {
fprintf(stderr, "Error searching %s\n",
path_name);
if (ignore_errors)
goto next;
goto out;
}
} else if (type == BTRFS_FT_SYMLINK) {
if (restore_symlinks)
ret = copy_symlink(root, &location, path_name);
if (ret < 0) {
if (ignore_errors)
goto next;
btrfs_free_path(path);
return ret;
}
}
next:
path->slots[0]++;
}
if (restore_metadata) {
snprintf(path_name, PATH_MAX, "%s%s", output_rootdir, in_dir);
fd = open(path_name, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "ERROR: Failed to access %s to restore metadata\n",
path_name);
if (!ignore_errors) {
ret = -1;
goto out;
}
} else {
/*
* Set owner/mode/time on the directory as well
*/
key->type = BTRFS_INODE_ITEM_KEY;
ret = copy_metadata(root, fd, key);
close(fd);
if (ret && !ignore_errors)
goto out;
}
}
if (verbose)
printf("Done searching %s\n", in_dir);
out:
btrfs_free_path(path);
return ret;
}
static int do_list_roots(struct btrfs_root *root)
{
struct btrfs_key key;
struct btrfs_key found_key;
struct btrfs_disk_key disk_key;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_root_item ri;
unsigned long offset;
int slot;
int ret;
root = root->fs_info->tree_root;
path = btrfs_alloc_path();
if (!path) {
fprintf(stderr, "Failed to alloc path\n");
return -ENOMEM;
}
key.offset = 0;
key.objectid = 0;
key.type = BTRFS_ROOT_ITEM_KEY;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0) {
fprintf(stderr, "Failed to do search %d\n", ret);
btrfs_free_path(path);
return -1;
}
leaf = path->nodes[0];
while (1) {
slot = path->slots[0];
if (slot >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, path);
if (ret)
break;
leaf = path->nodes[0];
slot = path->slots[0];
}
btrfs_item_key(leaf, &disk_key, slot);
btrfs_disk_key_to_cpu(&found_key, &disk_key);
if (btrfs_key_type(&found_key) != BTRFS_ROOT_ITEM_KEY) {
path->slots[0]++;
continue;
}
offset = btrfs_item_ptr_offset(leaf, slot);
read_extent_buffer(leaf, &ri, offset, sizeof(ri));
printf(" tree ");
btrfs_print_key(&disk_key);
printf(" %Lu level %d\n", btrfs_root_bytenr(&ri),
btrfs_root_level(&ri));
path->slots[0]++;
}
btrfs_free_path(path);
return 0;
}
static struct btrfs_root *open_fs(const char *dev, u64 root_location,
int super_mirror, int list_roots)
{
struct btrfs_fs_info *fs_info = NULL;
struct btrfs_root *root = NULL;
u64 bytenr;
int i;
for (i = super_mirror; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
fs_info = open_ctree_fs_info(dev, bytenr, root_location, 0,
OPEN_CTREE_PARTIAL);
if (fs_info)
break;
fprintf(stderr, "Could not open root, trying backup super\n");
}
if (!fs_info)
return NULL;
/*
* All we really need to succeed is reading the chunk tree, everything
* else we can do by hand, since we only need to read the tree root and
* the fs_root.
*/
if (!extent_buffer_uptodate(fs_info->tree_root->node)) {
u64 generation;
root = fs_info->tree_root;
if (!root_location)
root_location = btrfs_super_root(fs_info->super_copy);
generation = btrfs_super_generation(fs_info->super_copy);
root->node = read_tree_block(root, root_location,
root->nodesize, generation);
if (!extent_buffer_uptodate(root->node)) {
fprintf(stderr, "Error opening tree root\n");
close_ctree(root);
return NULL;
}
}
if (!list_roots && !fs_info->fs_root) {
struct btrfs_key key;
key.objectid = BTRFS_FS_TREE_OBJECTID;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
fs_info->fs_root = btrfs_read_fs_root_no_cache(fs_info, &key);
if (IS_ERR(fs_info->fs_root)) {
fprintf(stderr, "Couldn't read fs root: %ld\n",
PTR_ERR(fs_info->fs_root));
close_ctree(fs_info->tree_root);
return NULL;
}
}
if (list_roots && do_list_roots(fs_info->tree_root)) {
close_ctree(fs_info->tree_root);
return NULL;
}
return fs_info->fs_root;
}
static int find_first_dir(struct btrfs_root *root, u64 *objectid)
{
struct btrfs_path *path;
struct btrfs_key found_key;
struct btrfs_key key;
int ret = -1;
int i;
key.objectid = 0;
key.type = BTRFS_DIR_INDEX_KEY;
key.offset = 0;
path = btrfs_alloc_path();
if (!path) {
fprintf(stderr, "Ran out of memory\n");
return ret;
}
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0) {
fprintf(stderr, "Error searching %d\n", ret);
goto out;
}
if (!path->nodes[0]) {
fprintf(stderr, "No leaf!\n");
goto out;
}
again:
for (i = path->slots[0];
i < btrfs_header_nritems(path->nodes[0]); i++) {
btrfs_item_key_to_cpu(path->nodes[0], &found_key, i);
if (found_key.type != key.type)
continue;
printf("Using objectid %Lu for first dir\n",
found_key.objectid);
*objectid = found_key.objectid;
ret = 0;
goto out;
}
do {
ret = next_leaf(root, path);
if (ret < 0) {
fprintf(stderr, "Error getting next leaf %d\n",
ret);
goto out;
} else if (ret > 0) {
fprintf(stderr, "No more leaves\n");
goto out;
}
} while (!path->nodes[0]);
if (path->nodes[0])
goto again;
printf("Couldn't find a dir index item\n");
out:
btrfs_free_path(path);
return ret;
}
const char * const cmd_restore_usage[] = {
"btrfs restore [options] <device> <path> | -l <device>",
"Try to restore files from a damaged filesystem (unmounted)",
"",
"-s|--snapshots get snapshots",
"-x|--xattr get extended attributes",
"-m|--metadata restore owner, mode and times",
"-S|--symlinks restore symbolic links",
"-v|--verbose verbose",
"-i|--ignore-errors ignore errors",
"-o|--overwrite overwrite",
"-t <bytenr> tree location",
"-f <bytenr> filesystem location",
"-u|--super <mirror> super mirror",
"-r|--root <rootid> root objectid",
"-d find dir",
"-l|--list-roots list tree roots",
"-D|--dry-run dry run (only list files that would be recovered)",
"--path-regex <regex>",
" restore only filenames matching regex,",
" you have to use following syntax (possibly quoted):",
" ^/(|home(|/username(|/Desktop(|/.*))))$",
"-c ignore case (--path-regex only)",
NULL
};
int cmd_restore(int argc, char **argv)
{
struct btrfs_root *root;
struct btrfs_key key;
char dir_name[PATH_MAX];
u64 tree_location = 0;
u64 fs_location = 0;
u64 root_objectid = 0;
int len;
int ret;
int super_mirror = 0;
int find_dir = 0;
int list_roots = 0;
const char *match_regstr = NULL;
int match_cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
regex_t match_reg, *mreg = NULL;
char reg_err[256];
while (1) {
int opt;
static const struct option long_options[] = {
{ "path-regex", required_argument, NULL, 256},
{ "dry-run", no_argument, NULL, 'D'},
{ "metadata", no_argument, NULL, 'm'},
{ "symlinks", no_argument, NULL, 'S'},
{ "snapshots", no_argument, NULL, 's'},
{ "xattr", no_argument, NULL, 'x'},
{ "verbose", no_argument, NULL, 'v'},
{ "ignore-errors", no_argument, NULL, 'i'},
{ "overwrite", no_argument, NULL, 'o'},
{ "super", required_argument, NULL, 'u'},
{ "root", required_argument, NULL, 'r'},
{ "list-roots", no_argument, NULL, 'l'},
{ NULL, 0, NULL, 0}
};
opt = getopt_long(argc, argv, "sSxviot:u:dmf:r:lDc", long_options,
NULL);
if (opt < 0)
break;
switch (opt) {
case 's':
get_snaps = 1;
break;
case 'v':
verbose++;
break;
case 'i':
ignore_errors = 1;
break;
case 'o':
overwrite = 1;
break;
case 't':
tree_location = arg_strtou64(optarg);
break;
case 'f':
fs_location = arg_strtou64(optarg);
break;
case 'u':
super_mirror = arg_strtou64(optarg);
if (super_mirror >= BTRFS_SUPER_MIRROR_MAX) {
fprintf(stderr, "Super mirror not "
"valid\n");
exit(1);
}
break;
case 'd':
find_dir = 1;
break;
case 'r':
root_objectid = arg_strtou64(optarg);
if (!is_fstree(root_objectid)) {
fprintf(stderr, "objectid %llu is not a valid fs/file tree\n",
root_objectid);
exit(1);
}
break;
case 'l':
list_roots = 1;
break;
case 'm':
restore_metadata = 1;
break;
case 'S':
restore_symlinks = 1;
break;
case 'D':
dry_run = 1;
break;
case 'c':
match_cflags |= REG_ICASE;
break;
/* long option without single letter alternative */
case 256:
match_regstr = optarg;
break;
case 'x':
get_xattrs = 1;
break;
default:
usage(cmd_restore_usage);
}
}
if (!list_roots && check_argc_min(argc - optind, 2))
usage(cmd_restore_usage);
else if (list_roots && check_argc_min(argc - optind, 1))
usage(cmd_restore_usage);
if (fs_location && root_objectid) {
fprintf(stderr, "don't use -f and -r at the same time.\n");
return 1;
}
if ((ret = check_mounted(argv[optind])) < 0) {
fprintf(stderr, "Could not check mount status: %s\n",
strerror(-ret));
return 1;
} else if (ret) {
fprintf(stderr, "%s is currently mounted. Aborting.\n", argv[optind]);
return 1;
}
root = open_fs(argv[optind], tree_location, super_mirror, list_roots);
if (root == NULL)
return 1;
if (list_roots)
goto out;
if (fs_location != 0) {
free_extent_buffer(root->node);
root->node = read_tree_block(root, fs_location, root->nodesize, 0);
if (!extent_buffer_uptodate(root->node)) {
fprintf(stderr, "Failed to read fs location\n");
ret = 1;
goto out;
}
}
memset(path_name, 0, PATH_MAX);
if (strlen(argv[optind + 1]) >= PATH_MAX) {
fprintf(stderr, "ERROR: path too long\n");
ret = 1;
goto out;
}
strncpy(dir_name, argv[optind + 1], sizeof dir_name);
dir_name[sizeof dir_name - 1] = 0;
/* Strip the trailing / on the dir name */
len = strlen(dir_name);
while (len && dir_name[--len] == '/') {
dir_name[len] = '\0';
}
if (root_objectid != 0) {
struct btrfs_root *orig_root = root;
key.objectid = root_objectid;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
root = btrfs_read_fs_root(orig_root->fs_info, &key);
if (IS_ERR(root)) {
fprintf(stderr, "fail to read root %llu: %s\n",
root_objectid, strerror(-PTR_ERR(root)));
root = orig_root;
ret = 1;
goto out;
}
key.type = 0;
key.offset = 0;
}
if (find_dir) {
ret = find_first_dir(root, &key.objectid);
if (ret)
goto out;
} else {
key.objectid = BTRFS_FIRST_FREE_OBJECTID;
}
if (match_regstr) {
ret = regcomp(&match_reg, match_regstr, match_cflags);
if (ret) {
regerror(ret, &match_reg, reg_err, sizeof(reg_err));
fprintf(stderr, "Regex compile failed: %s\n", reg_err);
goto out;
}
mreg = &match_reg;
}
if (dry_run)
printf("This is a dry-run, no files are going to be restored\n");
ret = search_dir(root, &key, dir_name, "", mreg);
out:
if (mreg)
regfree(mreg);
close_ctree(root);
return !!ret;
}
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