linux/fs/bcachefs/fsck.c
Kent Overstreet 0728eed7b6 bcachefs: Fix a locking bug in fsck
This works around a btree locking issue - we can't be holding read locks
while taking write locks, which currently means we can't have live
iterators holding read locks at commit time.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:37 -04:00

1494 lines
34 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include "bcachefs.h"
#include "btree_update.h"
#include "dirent.h"
#include "error.h"
#include "fs-common.h"
#include "fsck.h"
#include "inode.h"
#include "keylist.h"
#include "super.h"
#include "xattr.h"
#include <linux/dcache.h> /* struct qstr */
#include <linux/generic-radix-tree.h>
#define QSTR(n) { { { .len = strlen(n) } }, .name = n }
static s64 bch2_count_inode_sectors(struct btree_trans *trans, u64 inum)
{
struct btree_iter *iter;
struct bkey_s_c k;
u64 sectors = 0;
int ret;
for_each_btree_key(trans, iter, BTREE_ID_EXTENTS,
POS(inum, 0), 0, k, ret) {
if (k.k->p.inode != inum)
break;
if (bkey_extent_is_allocation(k.k))
sectors += k.k->size;
}
bch2_trans_iter_free(trans, iter);
return ret ?: sectors;
}
static int __remove_dirent(struct btree_trans *trans,
struct bkey_s_c_dirent dirent)
{
struct bch_fs *c = trans->c;
struct qstr name;
struct bch_inode_unpacked dir_inode;
struct bch_hash_info dir_hash_info;
u64 dir_inum = dirent.k->p.inode;
int ret;
char *buf;
name.len = bch2_dirent_name_bytes(dirent);
buf = bch2_trans_kmalloc(trans, name.len + 1);
if (IS_ERR(buf))
return PTR_ERR(buf);
memcpy(buf, dirent.v->d_name, name.len);
buf[name.len] = '\0';
name.name = buf;
ret = bch2_inode_find_by_inum_trans(trans, dir_inum, &dir_inode);
if (ret && ret != -EINTR)
bch_err(c, "remove_dirent: err %i looking up directory inode", ret);
if (ret)
return ret;
dir_hash_info = bch2_hash_info_init(c, &dir_inode);
ret = bch2_hash_delete(trans, bch2_dirent_hash_desc,
&dir_hash_info, dir_inum, &name);
if (ret && ret != -EINTR)
bch_err(c, "remove_dirent: err %i deleting dirent", ret);
if (ret)
return ret;
return 0;
}
static int remove_dirent(struct btree_trans *trans,
struct bkey_s_c_dirent dirent)
{
return __bch2_trans_do(trans, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW,
__remove_dirent(trans, dirent));
}
static int reattach_inode(struct bch_fs *c,
struct bch_inode_unpacked *lostfound_inode,
u64 inum)
{
struct bch_inode_unpacked dir_u, inode_u;
char name_buf[20];
struct qstr name;
int ret;
snprintf(name_buf, sizeof(name_buf), "%llu", inum);
name = (struct qstr) QSTR(name_buf);
ret = bch2_trans_do(c, NULL, NULL,
BTREE_INSERT_LAZY_RW,
bch2_link_trans(&trans, lostfound_inode->bi_inum,
inum, &dir_u, &inode_u, &name));
if (ret)
bch_err(c, "error %i reattaching inode %llu", ret, inum);
return ret;
}
struct inode_walker {
bool first_this_inode;
bool have_inode;
u64 cur_inum;
struct bch_inode_unpacked inode;
};
static struct inode_walker inode_walker_init(void)
{
return (struct inode_walker) {
.cur_inum = -1,
.have_inode = false,
};
}
static int walk_inode(struct btree_trans *trans,
struct inode_walker *w, u64 inum)
{
if (inum != w->cur_inum) {
int ret = bch2_inode_find_by_inum_trans(trans, inum,
&w->inode);
if (ret && ret != -ENOENT)
return ret;
w->have_inode = !ret;
w->cur_inum = inum;
w->first_this_inode = true;
} else {
w->first_this_inode = false;
}
return 0;
}
struct hash_check {
struct bch_hash_info info;
/* start of current chain of hash collisions: */
struct btree_iter *chain;
/* next offset in current chain of hash collisions: */
u64 chain_end;
};
static void hash_check_init(struct hash_check *h)
{
h->chain = NULL;
h->chain_end = 0;
}
static void hash_stop_chain(struct btree_trans *trans,
struct hash_check *h)
{
if (h->chain)
bch2_trans_iter_free(trans, h->chain);
h->chain = NULL;
}
static void hash_check_set_inode(struct btree_trans *trans,
struct hash_check *h,
const struct bch_inode_unpacked *bi)
{
h->info = bch2_hash_info_init(trans->c, bi);
hash_stop_chain(trans, h);
}
static int hash_redo_key(const struct bch_hash_desc desc,
struct btree_trans *trans, struct hash_check *h,
struct btree_iter *k_iter, struct bkey_s_c k,
u64 hashed)
{
struct bkey_i delete;
struct bkey_i *tmp;
tmp = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
if (IS_ERR(tmp))
return PTR_ERR(tmp);
bkey_reassemble(tmp, k);
bkey_init(&delete.k);
delete.k.p = k_iter->pos;
bch2_trans_update(trans, k_iter, &delete, 0);
return bch2_hash_set(trans, desc, &h->info, k_iter->pos.inode,
tmp, BCH_HASH_SET_MUST_CREATE);
}
static int fsck_hash_delete_at(struct btree_trans *trans,
const struct bch_hash_desc desc,
struct bch_hash_info *info,
struct btree_iter *iter)
{
int ret;
retry:
ret = bch2_hash_delete_at(trans, desc, info, iter) ?:
bch2_trans_commit(trans, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW);
if (ret == -EINTR) {
ret = bch2_btree_iter_traverse(iter);
if (!ret)
goto retry;
}
return ret;
}
static int hash_check_duplicates(struct btree_trans *trans,
const struct bch_hash_desc desc, struct hash_check *h,
struct btree_iter *k_iter, struct bkey_s_c k)
{
struct bch_fs *c = trans->c;
struct btree_iter *iter;
struct bkey_s_c k2;
char buf[200];
int ret = 0;
if (!bkey_cmp(h->chain->pos, k_iter->pos))
return 0;
iter = bch2_trans_copy_iter(trans, h->chain);
BUG_ON(IS_ERR(iter));
for_each_btree_key_continue(iter, 0, k2, ret) {
if (bkey_cmp(k2.k->p, k.k->p) >= 0)
break;
if (fsck_err_on(k2.k->type == desc.key_type &&
!desc.cmp_bkey(k, k2), c,
"duplicate hash table keys:\n%s",
(bch2_bkey_val_to_text(&PBUF(buf), c,
k), buf))) {
ret = fsck_hash_delete_at(trans, desc, &h->info, k_iter);
if (ret)
return ret;
ret = 1;
break;
}
}
fsck_err:
bch2_trans_iter_free(trans, iter);
return ret;
}
static void hash_set_chain_start(struct btree_trans *trans,
const struct bch_hash_desc desc,
struct hash_check *h,
struct btree_iter *k_iter, struct bkey_s_c k)
{
bool hole = (k.k->type != KEY_TYPE_whiteout &&
k.k->type != desc.key_type);
if (hole || k.k->p.offset > h->chain_end + 1)
hash_stop_chain(trans, h);
if (!hole) {
if (!h->chain) {
h->chain = bch2_trans_copy_iter(trans, k_iter);
BUG_ON(IS_ERR(h->chain));
}
h->chain_end = k.k->p.offset;
}
}
static bool key_has_correct_hash(struct btree_trans *trans,
const struct bch_hash_desc desc,
struct hash_check *h,
struct btree_iter *k_iter, struct bkey_s_c k)
{
u64 hash;
hash_set_chain_start(trans, desc, h, k_iter, k);
if (k.k->type != desc.key_type)
return true;
hash = desc.hash_bkey(&h->info, k);
return hash >= h->chain->pos.offset &&
hash <= k.k->p.offset;
}
static int hash_check_key(struct btree_trans *trans,
const struct bch_hash_desc desc, struct hash_check *h,
struct btree_iter *k_iter, struct bkey_s_c k)
{
struct bch_fs *c = trans->c;
char buf[200];
u64 hashed;
int ret = 0;
hash_set_chain_start(trans, desc, h, k_iter, k);
if (k.k->type != desc.key_type)
return 0;
hashed = desc.hash_bkey(&h->info, k);
if (fsck_err_on(hashed < h->chain->pos.offset ||
hashed > k.k->p.offset, c,
"hash table key at wrong offset: btree %u, %llu, "
"hashed to %llu chain starts at %llu\n%s",
desc.btree_id, k.k->p.offset,
hashed, h->chain->pos.offset,
(bch2_bkey_val_to_text(&PBUF(buf), c, k), buf))) {
ret = __bch2_trans_do(trans, NULL, NULL,
BTREE_INSERT_NOFAIL|BTREE_INSERT_LAZY_RW,
hash_redo_key(desc, trans, h, k_iter, k, hashed));
if (ret) {
bch_err(c, "hash_redo_key err %i", ret);
return ret;
}
return 1;
}
ret = hash_check_duplicates(trans, desc, h, k_iter, k);
fsck_err:
return ret;
}
static int check_dirent_hash(struct btree_trans *trans, struct hash_check *h,
struct btree_iter *iter, struct bkey_s_c *k)
{
struct bch_fs *c = trans->c;
struct bkey_i_dirent *d = NULL;
int ret = -EINVAL;
char buf[200];
unsigned len;
u64 hash;
if (key_has_correct_hash(trans, bch2_dirent_hash_desc, h, iter, *k))
return 0;
len = bch2_dirent_name_bytes(bkey_s_c_to_dirent(*k));
BUG_ON(!len);
memcpy(buf, bkey_s_c_to_dirent(*k).v->d_name, len);
buf[len] = '\0';
d = kmalloc(bkey_bytes(k->k), GFP_KERNEL);
if (!d) {
bch_err(c, "memory allocation failure");
return -ENOMEM;
}
bkey_reassemble(&d->k_i, *k);
do {
--len;
if (!len)
goto err_redo;
d->k.u64s = BKEY_U64s + dirent_val_u64s(len);
BUG_ON(bkey_val_bytes(&d->k) <
offsetof(struct bch_dirent, d_name) + len);
memset(d->v.d_name + len, 0,
bkey_val_bytes(&d->k) -
offsetof(struct bch_dirent, d_name) - len);
hash = bch2_dirent_hash_desc.hash_bkey(&h->info,
bkey_i_to_s_c(&d->k_i));
} while (hash < h->chain->pos.offset ||
hash > k->k->p.offset);
if (fsck_err(c, "dirent with junk at end, was %s (%zu) now %s (%u)",
buf, strlen(buf), d->v.d_name, len)) {
ret = __bch2_trans_do(trans, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW,
(bch2_trans_update(trans, iter, &d->k_i, 0), 0));
if (ret)
goto err;
*k = bch2_btree_iter_peek(iter);
BUG_ON(k->k->type != KEY_TYPE_dirent);
}
err:
fsck_err:
kfree(d);
return ret;
err_redo:
hash = bch2_dirent_hash_desc.hash_bkey(&h->info, *k);
if (fsck_err(c, "cannot fix dirent by removing trailing garbage %s (%zu)\n"
"hash table key at wrong offset: btree %u, offset %llu, "
"hashed to %llu chain starts at %llu\n%s",
buf, strlen(buf), BTREE_ID_DIRENTS,
k->k->p.offset, hash, h->chain->pos.offset,
(bch2_bkey_val_to_text(&PBUF(buf), c,
*k), buf))) {
ret = __bch2_trans_do(trans, NULL, NULL,
BTREE_INSERT_NOFAIL|BTREE_INSERT_LAZY_RW,
hash_redo_key(bch2_dirent_hash_desc, trans,
h, iter, *k, hash));
if (ret)
bch_err(c, "hash_redo_key err %i", ret);
else
ret = 1;
}
goto err;
}
static int bch2_inode_truncate(struct bch_fs *c, u64 inode_nr, u64 new_size)
{
return bch2_btree_delete_range(c, BTREE_ID_EXTENTS,
POS(inode_nr, round_up(new_size, block_bytes(c)) >> 9),
POS(inode_nr + 1, 0), NULL);
}
static int bch2_fix_overlapping_extent(struct btree_trans *trans,
struct btree_iter *iter,
struct bkey_s_c k, struct bpos cut_at)
{
struct btree_iter *u_iter;
struct bkey_i *u;
int ret;
u = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
ret = PTR_ERR_OR_ZERO(u);
if (ret)
return ret;
bkey_reassemble(u, k);
bch2_cut_front(cut_at, u);
u_iter = bch2_trans_copy_iter(trans, iter);
ret = PTR_ERR_OR_ZERO(u_iter);
if (ret)
return ret;
/*
* We don't want to go through the
* extent_handle_overwrites path:
*/
__bch2_btree_iter_set_pos(u_iter, u->k.p, false);
/*
* XXX: this is going to leave disk space
* accounting slightly wrong
*/
ret = bch2_trans_update(trans, u_iter, u, 0);
bch2_trans_iter_put(trans, u_iter);
return ret;
}
/*
* Walk extents: verify that extents have a corresponding S_ISREG inode, and
* that i_size an i_sectors are consistent
*/
noinline_for_stack
static int check_extents(struct bch_fs *c)
{
struct inode_walker w = inode_walker_init();
struct btree_trans trans;
struct btree_iter *iter;
struct bkey_s_c k;
struct bkey prev = KEY(0, 0, 0);
u64 i_sectors;
int ret = 0;
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
bch_verbose(c, "checking extents");
iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS,
POS(BCACHEFS_ROOT_INO, 0),
BTREE_ITER_INTENT);
retry:
for_each_btree_key_continue(iter, 0, k, ret) {
if (bkey_cmp(prev.p, bkey_start_pos(k.k)) > 0) {
char buf1[100];
char buf2[100];
bch2_bkey_to_text(&PBUF(buf1), &prev);
bch2_bkey_to_text(&PBUF(buf2), k.k);
if (fsck_err(c, "overlapping extents: %s, %s", buf1, buf2)) {
ret = __bch2_trans_do(&trans, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW,
bch2_fix_overlapping_extent(&trans,
iter, k, prev.p));
if (ret)
goto err;
}
}
prev = *k.k;
ret = walk_inode(&trans, &w, k.k->p.inode);
if (ret)
break;
if (fsck_err_on(!w.have_inode, c,
"extent type %u for missing inode %llu",
k.k->type, k.k->p.inode) ||
fsck_err_on(w.have_inode &&
!S_ISREG(w.inode.bi_mode) && !S_ISLNK(w.inode.bi_mode), c,
"extent type %u for non regular file, inode %llu mode %o",
k.k->type, k.k->p.inode, w.inode.bi_mode)) {
bch2_trans_unlock(&trans);
ret = bch2_inode_truncate(c, k.k->p.inode, 0);
if (ret)
goto err;
continue;
}
if (fsck_err_on(w.first_this_inode &&
w.have_inode &&
!(w.inode.bi_flags & BCH_INODE_I_SECTORS_DIRTY) &&
w.inode.bi_sectors !=
(i_sectors = bch2_count_inode_sectors(&trans, w.cur_inum)),
c, "i_sectors wrong: got %llu, should be %llu",
w.inode.bi_sectors, i_sectors)) {
struct bkey_inode_buf p;
w.inode.bi_sectors = i_sectors;
bch2_trans_unlock(&trans);
bch2_inode_pack(&p, &w.inode);
ret = bch2_btree_insert(c, BTREE_ID_INODES,
&p.inode.k_i, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW);
if (ret) {
bch_err(c, "error in fsck: error %i updating inode", ret);
goto err;
}
/* revalidate iterator: */
k = bch2_btree_iter_peek(iter);
}
if (fsck_err_on(w.have_inode &&
!(w.inode.bi_flags & BCH_INODE_I_SIZE_DIRTY) &&
k.k->type != KEY_TYPE_reservation &&
k.k->p.offset > round_up(w.inode.bi_size, block_bytes(c)) >> 9, c,
"extent type %u offset %llu past end of inode %llu, i_size %llu",
k.k->type, k.k->p.offset, k.k->p.inode, w.inode.bi_size)) {
bch2_trans_unlock(&trans);
ret = bch2_inode_truncate(c, k.k->p.inode,
w.inode.bi_size);
if (ret)
goto err;
continue;
}
}
err:
fsck_err:
if (ret == -EINTR)
goto retry;
return bch2_trans_exit(&trans) ?: ret;
}
/*
* Walk dirents: verify that they all have a corresponding S_ISDIR inode,
* validate d_type
*/
noinline_for_stack
static int check_dirents(struct bch_fs *c)
{
struct inode_walker w = inode_walker_init();
struct hash_check h;
struct btree_trans trans;
struct btree_iter *iter;
struct bkey_s_c k;
unsigned name_len;
char buf[200];
int ret = 0;
bch_verbose(c, "checking dirents");
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
hash_check_init(&h);
iter = bch2_trans_get_iter(&trans, BTREE_ID_DIRENTS,
POS(BCACHEFS_ROOT_INO, 0), 0);
retry:
for_each_btree_key_continue(iter, 0, k, ret) {
struct bkey_s_c_dirent d;
struct bch_inode_unpacked target;
bool have_target;
u64 d_inum;
ret = walk_inode(&trans, &w, k.k->p.inode);
if (ret)
break;
if (fsck_err_on(!w.have_inode, c,
"dirent in nonexisting directory:\n%s",
(bch2_bkey_val_to_text(&PBUF(buf), c,
k), buf)) ||
fsck_err_on(!S_ISDIR(w.inode.bi_mode), c,
"dirent in non directory inode type %u:\n%s",
mode_to_type(w.inode.bi_mode),
(bch2_bkey_val_to_text(&PBUF(buf), c,
k), buf))) {
ret = bch2_btree_delete_at(&trans, iter, 0);
if (ret)
goto err;
continue;
}
if (w.first_this_inode && w.have_inode)
hash_check_set_inode(&trans, &h, &w.inode);
ret = check_dirent_hash(&trans, &h, iter, &k);
if (ret > 0) {
ret = 0;
continue;
}
if (ret)
goto fsck_err;
if (ret)
goto fsck_err;
if (k.k->type != KEY_TYPE_dirent)
continue;
d = bkey_s_c_to_dirent(k);
d_inum = le64_to_cpu(d.v->d_inum);
name_len = bch2_dirent_name_bytes(d);
if (fsck_err_on(!name_len, c, "empty dirent") ||
fsck_err_on(name_len == 1 &&
!memcmp(d.v->d_name, ".", 1), c,
". dirent") ||
fsck_err_on(name_len == 2 &&
!memcmp(d.v->d_name, "..", 2), c,
".. dirent") ||
fsck_err_on(name_len == 2 &&
!memcmp(d.v->d_name, "..", 2), c,
".. dirent") ||
fsck_err_on(memchr(d.v->d_name, '/', name_len), c,
"dirent name has invalid chars")) {
ret = remove_dirent(&trans, d);
if (ret)
goto err;
continue;
}
if (fsck_err_on(d_inum == d.k->p.inode, c,
"dirent points to own directory:\n%s",
(bch2_bkey_val_to_text(&PBUF(buf), c,
k), buf))) {
ret = remove_dirent(&trans, d);
if (ret)
goto err;
continue;
}
ret = bch2_inode_find_by_inum_trans(&trans, d_inum, &target);
if (ret && ret != -ENOENT)
break;
have_target = !ret;
ret = 0;
if (fsck_err_on(!have_target, c,
"dirent points to missing inode:\n%s",
(bch2_bkey_val_to_text(&PBUF(buf), c,
k), buf))) {
ret = remove_dirent(&trans, d);
if (ret)
goto err;
continue;
}
if (fsck_err_on(have_target &&
d.v->d_type !=
mode_to_type(target.bi_mode), c,
"incorrect d_type: should be %u:\n%s",
mode_to_type(target.bi_mode),
(bch2_bkey_val_to_text(&PBUF(buf), c,
k), buf))) {
struct bkey_i_dirent *n;
n = kmalloc(bkey_bytes(d.k), GFP_KERNEL);
if (!n) {
ret = -ENOMEM;
goto err;
}
bkey_reassemble(&n->k_i, d.s_c);
n->v.d_type = mode_to_type(target.bi_mode);
ret = __bch2_trans_do(&trans, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW,
(bch2_trans_update(&trans, iter, &n->k_i, 0), 0));
kfree(n);
if (ret)
goto err;
}
}
hash_stop_chain(&trans, &h);
err:
fsck_err:
if (ret == -EINTR)
goto retry;
return bch2_trans_exit(&trans) ?: ret;
}
/*
* Walk xattrs: verify that they all have a corresponding inode
*/
noinline_for_stack
static int check_xattrs(struct bch_fs *c)
{
struct inode_walker w = inode_walker_init();
struct hash_check h;
struct btree_trans trans;
struct btree_iter *iter;
struct bkey_s_c k;
int ret = 0;
bch_verbose(c, "checking xattrs");
hash_check_init(&h);
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
iter = bch2_trans_get_iter(&trans, BTREE_ID_XATTRS,
POS(BCACHEFS_ROOT_INO, 0), 0);
retry:
for_each_btree_key_continue(iter, 0, k, ret) {
ret = walk_inode(&trans, &w, k.k->p.inode);
if (ret)
break;
if (fsck_err_on(!w.have_inode, c,
"xattr for missing inode %llu",
k.k->p.inode)) {
ret = bch2_btree_delete_at(&trans, iter, 0);
if (ret)
goto err;
continue;
}
if (w.first_this_inode && w.have_inode)
hash_check_set_inode(&trans, &h, &w.inode);
ret = hash_check_key(&trans, bch2_xattr_hash_desc,
&h, iter, k);
if (ret)
goto fsck_err;
}
err:
fsck_err:
if (ret == -EINTR)
goto retry;
return bch2_trans_exit(&trans) ?: ret;
}
/* Get root directory, create if it doesn't exist: */
static int check_root(struct bch_fs *c, struct bch_inode_unpacked *root_inode)
{
struct bkey_inode_buf packed;
int ret;
bch_verbose(c, "checking root directory");
ret = bch2_inode_find_by_inum(c, BCACHEFS_ROOT_INO, root_inode);
if (ret && ret != -ENOENT)
return ret;
if (fsck_err_on(ret, c, "root directory missing"))
goto create_root;
if (fsck_err_on(!S_ISDIR(root_inode->bi_mode), c,
"root inode not a directory"))
goto create_root;
return 0;
fsck_err:
return ret;
create_root:
bch2_inode_init(c, root_inode, 0, 0, S_IFDIR|0755,
0, NULL);
root_inode->bi_inum = BCACHEFS_ROOT_INO;
bch2_inode_pack(&packed, root_inode);
return bch2_btree_insert(c, BTREE_ID_INODES, &packed.inode.k_i,
NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW);
}
/* Get lost+found, create if it doesn't exist: */
static int check_lostfound(struct bch_fs *c,
struct bch_inode_unpacked *root_inode,
struct bch_inode_unpacked *lostfound_inode)
{
struct qstr lostfound = QSTR("lost+found");
struct bch_hash_info root_hash_info =
bch2_hash_info_init(c, root_inode);
u64 inum;
int ret;
bch_verbose(c, "checking lost+found");
inum = bch2_dirent_lookup(c, BCACHEFS_ROOT_INO, &root_hash_info,
&lostfound);
if (!inum) {
bch_notice(c, "creating lost+found");
goto create_lostfound;
}
ret = bch2_inode_find_by_inum(c, inum, lostfound_inode);
if (ret && ret != -ENOENT)
return ret;
if (fsck_err_on(ret, c, "lost+found missing"))
goto create_lostfound;
if (fsck_err_on(!S_ISDIR(lostfound_inode->bi_mode), c,
"lost+found inode not a directory"))
goto create_lostfound;
return 0;
fsck_err:
return ret;
create_lostfound:
bch2_inode_init_early(c, lostfound_inode);
ret = bch2_trans_do(c, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW,
bch2_create_trans(&trans,
BCACHEFS_ROOT_INO, root_inode,
lostfound_inode, &lostfound,
0, 0, S_IFDIR|0700, 0, NULL, NULL));
if (ret)
bch_err(c, "error creating lost+found: %i", ret);
return ret;
}
struct inode_bitmap {
unsigned long *bits;
size_t size;
};
static inline bool inode_bitmap_test(struct inode_bitmap *b, size_t nr)
{
return nr < b->size ? test_bit(nr, b->bits) : false;
}
static inline int inode_bitmap_set(struct inode_bitmap *b, size_t nr)
{
if (nr >= b->size) {
size_t new_size = max_t(size_t, max_t(size_t,
PAGE_SIZE * 8,
b->size * 2),
nr + 1);
void *n;
new_size = roundup_pow_of_two(new_size);
n = krealloc(b->bits, new_size / 8, GFP_KERNEL|__GFP_ZERO);
if (!n) {
return -ENOMEM;
}
b->bits = n;
b->size = new_size;
}
__set_bit(nr, b->bits);
return 0;
}
struct pathbuf {
size_t nr;
size_t size;
struct pathbuf_entry {
u64 inum;
u64 offset;
} *entries;
};
static int path_down(struct pathbuf *p, u64 inum)
{
if (p->nr == p->size) {
size_t new_size = max_t(size_t, 256UL, p->size * 2);
void *n = krealloc(p->entries,
new_size * sizeof(p->entries[0]),
GFP_KERNEL);
if (!n)
return -ENOMEM;
p->entries = n;
p->size = new_size;
};
p->entries[p->nr++] = (struct pathbuf_entry) {
.inum = inum,
.offset = 0,
};
return 0;
}
noinline_for_stack
static int check_directory_structure(struct bch_fs *c,
struct bch_inode_unpacked *lostfound_inode)
{
struct inode_bitmap dirs_done = { NULL, 0 };
struct pathbuf path = { 0, 0, NULL };
struct pathbuf_entry *e;
struct btree_trans trans;
struct btree_iter *iter;
struct bkey_s_c k;
struct bkey_s_c_dirent dirent;
bool had_unreachable;
u64 d_inum;
int ret = 0;
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
bch_verbose(c, "checking directory structure");
/* DFS: */
restart_dfs:
had_unreachable = false;
ret = inode_bitmap_set(&dirs_done, BCACHEFS_ROOT_INO);
if (ret) {
bch_err(c, "memory allocation failure in inode_bitmap_set()");
goto err;
}
ret = path_down(&path, BCACHEFS_ROOT_INO);
if (ret)
goto err;
while (path.nr) {
next:
e = &path.entries[path.nr - 1];
if (e->offset == U64_MAX)
goto up;
for_each_btree_key(&trans, iter, BTREE_ID_DIRENTS,
POS(e->inum, e->offset + 1), 0, k, ret) {
if (k.k->p.inode != e->inum)
break;
e->offset = k.k->p.offset;
if (k.k->type != KEY_TYPE_dirent)
continue;
dirent = bkey_s_c_to_dirent(k);
if (dirent.v->d_type != DT_DIR)
continue;
d_inum = le64_to_cpu(dirent.v->d_inum);
if (fsck_err_on(inode_bitmap_test(&dirs_done, d_inum), c,
"directory %llu has multiple hardlinks",
d_inum)) {
ret = remove_dirent(&trans, dirent);
if (ret)
goto err;
continue;
}
ret = inode_bitmap_set(&dirs_done, d_inum);
if (ret) {
bch_err(c, "memory allocation failure in inode_bitmap_set()");
goto err;
}
ret = path_down(&path, d_inum);
if (ret) {
goto err;
}
ret = bch2_trans_iter_free(&trans, iter);
if (ret) {
bch_err(c, "btree error %i in fsck", ret);
goto err;
}
goto next;
}
ret = bch2_trans_iter_free(&trans, iter) ?: ret;
if (ret) {
bch_err(c, "btree error %i in fsck", ret);
goto err;
}
up:
path.nr--;
}
iter = bch2_trans_get_iter(&trans, BTREE_ID_INODES, POS_MIN, 0);
retry:
for_each_btree_key_continue(iter, 0, k, ret) {
if (k.k->type != KEY_TYPE_inode)
continue;
if (!S_ISDIR(le16_to_cpu(bkey_s_c_to_inode(k).v->bi_mode)))
continue;
ret = bch2_empty_dir_trans(&trans, k.k->p.inode);
if (ret == -EINTR)
goto retry;
if (!ret)
continue;
if (fsck_err_on(!inode_bitmap_test(&dirs_done, k.k->p.inode), c,
"unreachable directory found (inum %llu)",
k.k->p.inode)) {
bch2_trans_unlock(&trans);
ret = reattach_inode(c, lostfound_inode, k.k->p.inode);
if (ret) {
goto err;
}
had_unreachable = true;
}
}
bch2_trans_iter_free(&trans, iter);
if (ret)
goto err;
if (had_unreachable) {
bch_info(c, "reattached unreachable directories, restarting pass to check for loops");
kfree(dirs_done.bits);
kfree(path.entries);
memset(&dirs_done, 0, sizeof(dirs_done));
memset(&path, 0, sizeof(path));
goto restart_dfs;
}
err:
fsck_err:
ret = bch2_trans_exit(&trans) ?: ret;
kfree(dirs_done.bits);
kfree(path.entries);
return ret;
}
struct nlink {
u32 count;
u32 dir_count;
};
typedef GENRADIX(struct nlink) nlink_table;
static void inc_link(struct bch_fs *c, nlink_table *links,
u64 range_start, u64 *range_end,
u64 inum, bool dir)
{
struct nlink *link;
if (inum < range_start || inum >= *range_end)
return;
link = genradix_ptr_alloc(links, inum - range_start, GFP_KERNEL);
if (!link) {
bch_verbose(c, "allocation failed during fsck - will need another pass");
*range_end = inum;
return;
}
if (dir)
link->dir_count++;
else
link->count++;
}
noinline_for_stack
static int bch2_gc_walk_dirents(struct bch_fs *c, nlink_table *links,
u64 range_start, u64 *range_end)
{
struct btree_trans trans;
struct btree_iter *iter;
struct bkey_s_c k;
struct bkey_s_c_dirent d;
u64 d_inum;
int ret;
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
inc_link(c, links, range_start, range_end, BCACHEFS_ROOT_INO, false);
for_each_btree_key(&trans, iter, BTREE_ID_DIRENTS, POS_MIN, 0, k, ret) {
switch (k.k->type) {
case KEY_TYPE_dirent:
d = bkey_s_c_to_dirent(k);
d_inum = le64_to_cpu(d.v->d_inum);
if (d.v->d_type == DT_DIR)
inc_link(c, links, range_start, range_end,
d.k->p.inode, true);
inc_link(c, links, range_start, range_end,
d_inum, false);
break;
}
bch2_trans_cond_resched(&trans);
}
ret = bch2_trans_exit(&trans) ?: ret;
if (ret)
bch_err(c, "error in fsck: btree error %i while walking dirents", ret);
return ret;
}
static int check_inode_nlink(struct bch_fs *c,
struct bch_inode_unpacked *lostfound_inode,
struct bch_inode_unpacked *u,
struct nlink *link,
bool *do_update)
{
u32 i_nlink = bch2_inode_nlink_get(u);
u32 real_i_nlink =
link->count * nlink_bias(u->bi_mode) +
link->dir_count;
int ret = 0;
/*
* These should have been caught/fixed by earlier passes, we don't
* repair them here:
*/
if (S_ISDIR(u->bi_mode) && link->count > 1) {
need_fsck_err(c, "directory %llu with multiple hardlinks: %u",
u->bi_inum, link->count);
return 0;
}
if (S_ISDIR(u->bi_mode) && !link->count) {
need_fsck_err(c, "unreachable directory found (inum %llu)",
u->bi_inum);
return 0;
}
if (!S_ISDIR(u->bi_mode) && link->dir_count) {
need_fsck_err(c, "non directory with subdirectories",
u->bi_inum);
return 0;
}
if (!link->count &&
!(u->bi_flags & BCH_INODE_UNLINKED) &&
(c->sb.features & (1 << BCH_FEATURE_atomic_nlink))) {
if (fsck_err(c, "unreachable inode %llu not marked as unlinked (type %u)",
u->bi_inum, mode_to_type(u->bi_mode)) ==
FSCK_ERR_IGNORE)
return 0;
ret = reattach_inode(c, lostfound_inode, u->bi_inum);
if (ret)
return ret;
link->count = 1;
real_i_nlink = nlink_bias(u->bi_mode) + link->dir_count;
goto set_i_nlink;
}
if (i_nlink < link->count) {
if (fsck_err(c, "inode %llu i_link too small (%u < %u, type %i)",
u->bi_inum, i_nlink, link->count,
mode_to_type(u->bi_mode)) == FSCK_ERR_IGNORE)
return 0;
goto set_i_nlink;
}
if (i_nlink != real_i_nlink &&
c->sb.clean) {
if (fsck_err(c, "filesystem marked clean, "
"but inode %llu has wrong i_nlink "
"(type %u i_nlink %u, should be %u)",
u->bi_inum, mode_to_type(u->bi_mode),
i_nlink, real_i_nlink) == FSCK_ERR_IGNORE)
return 0;
goto set_i_nlink;
}
if (i_nlink != real_i_nlink &&
(c->sb.features & (1 << BCH_FEATURE_atomic_nlink))) {
if (fsck_err(c, "inode %llu has wrong i_nlink "
"(type %u i_nlink %u, should be %u)",
u->bi_inum, mode_to_type(u->bi_mode),
i_nlink, real_i_nlink) == FSCK_ERR_IGNORE)
return 0;
goto set_i_nlink;
}
if (real_i_nlink && i_nlink != real_i_nlink)
bch_verbose(c, "setting inode %llu nlink from %u to %u",
u->bi_inum, i_nlink, real_i_nlink);
set_i_nlink:
if (i_nlink != real_i_nlink) {
bch2_inode_nlink_set(u, real_i_nlink);
*do_update = true;
}
fsck_err:
return ret;
}
static int check_inode(struct btree_trans *trans,
struct bch_inode_unpacked *lostfound_inode,
struct btree_iter *iter,
struct bkey_s_c_inode inode,
struct nlink *link)
{
struct bch_fs *c = trans->c;
struct bch_inode_unpacked u;
bool do_update = false;
int ret = 0;
ret = bch2_inode_unpack(inode, &u);
bch2_trans_unlock(trans);
if (bch2_fs_inconsistent_on(ret, c,
"error unpacking inode %llu in fsck",
inode.k->p.inode))
return ret;
if (link) {
ret = check_inode_nlink(c, lostfound_inode, &u, link,
&do_update);
if (ret)
return ret;
}
if (u.bi_flags & BCH_INODE_UNLINKED &&
(!c->sb.clean ||
fsck_err(c, "filesystem marked clean, but inode %llu unlinked",
u.bi_inum))) {
bch_verbose(c, "deleting inode %llu", u.bi_inum);
ret = bch2_inode_rm(c, u.bi_inum);
if (ret)
bch_err(c, "error in fsck: error %i while deleting inode", ret);
return ret;
}
if (u.bi_flags & BCH_INODE_I_SIZE_DIRTY &&
(!c->sb.clean ||
fsck_err(c, "filesystem marked clean, but inode %llu has i_size dirty",
u.bi_inum))) {
bch_verbose(c, "truncating inode %llu", u.bi_inum);
/*
* XXX: need to truncate partial blocks too here - or ideally
* just switch units to bytes and that issue goes away
*/
ret = bch2_inode_truncate(c, u.bi_inum, u.bi_size);
if (ret) {
bch_err(c, "error in fsck: error %i truncating inode", ret);
return ret;
}
/*
* We truncated without our normal sector accounting hook, just
* make sure we recalculate it:
*/
u.bi_flags |= BCH_INODE_I_SECTORS_DIRTY;
u.bi_flags &= ~BCH_INODE_I_SIZE_DIRTY;
do_update = true;
}
if (u.bi_flags & BCH_INODE_I_SECTORS_DIRTY &&
(!c->sb.clean ||
fsck_err(c, "filesystem marked clean, but inode %llu has i_sectors dirty",
u.bi_inum))) {
s64 sectors;
bch_verbose(c, "recounting sectors for inode %llu",
u.bi_inum);
sectors = bch2_count_inode_sectors(trans, u.bi_inum);
if (sectors < 0) {
bch_err(c, "error in fsck: error %i recounting inode sectors",
(int) sectors);
return sectors;
}
u.bi_sectors = sectors;
u.bi_flags &= ~BCH_INODE_I_SECTORS_DIRTY;
do_update = true;
}
if (do_update) {
struct bkey_inode_buf p;
bch2_inode_pack(&p, &u);
ret = __bch2_trans_do(trans, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW,
(bch2_trans_update(trans, iter, &p.inode.k_i, 0), 0));
if (ret)
bch_err(c, "error in fsck: error %i "
"updating inode", ret);
}
fsck_err:
return ret;
}
noinline_for_stack
static int bch2_gc_walk_inodes(struct bch_fs *c,
struct bch_inode_unpacked *lostfound_inode,
nlink_table *links,
u64 range_start, u64 range_end)
{
struct btree_trans trans;
struct btree_iter *iter;
struct bkey_s_c k;
struct nlink *link, zero_links = { 0, 0 };
struct genradix_iter nlinks_iter;
int ret = 0, ret2 = 0;
u64 nlinks_pos;
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
iter = bch2_trans_get_iter(&trans, BTREE_ID_INODES,
POS(range_start, 0), 0);
nlinks_iter = genradix_iter_init(links, 0);
while ((k = bch2_btree_iter_peek(iter)).k &&
!(ret2 = bkey_err(k))) {
peek_nlinks: link = genradix_iter_peek(&nlinks_iter, links);
if (!link && (!k.k || iter->pos.inode >= range_end))
break;
nlinks_pos = range_start + nlinks_iter.pos;
if (iter->pos.inode > nlinks_pos) {
/* Should have been caught by dirents pass: */
need_fsck_err_on(link && link->count, c,
"missing inode %llu (nlink %u)",
nlinks_pos, link->count);
genradix_iter_advance(&nlinks_iter, links);
goto peek_nlinks;
}
if (iter->pos.inode < nlinks_pos || !link)
link = &zero_links;
if (k.k && k.k->type == KEY_TYPE_inode) {
ret = check_inode(&trans, lostfound_inode, iter,
bkey_s_c_to_inode(k), link);
BUG_ON(ret == -EINTR);
if (ret)
break;
} else {
/* Should have been caught by dirents pass: */
need_fsck_err_on(link->count, c,
"missing inode %llu (nlink %u)",
nlinks_pos, link->count);
}
if (nlinks_pos == iter->pos.inode)
genradix_iter_advance(&nlinks_iter, links);
bch2_btree_iter_next(iter);
bch2_trans_cond_resched(&trans);
}
fsck_err:
bch2_trans_exit(&trans);
if (ret2)
bch_err(c, "error in fsck: btree error %i while walking inodes", ret2);
return ret ?: ret2;
}
noinline_for_stack
static int check_inode_nlinks(struct bch_fs *c,
struct bch_inode_unpacked *lostfound_inode)
{
nlink_table links;
u64 this_iter_range_start, next_iter_range_start = 0;
int ret = 0;
bch_verbose(c, "checking inode nlinks");
genradix_init(&links);
do {
this_iter_range_start = next_iter_range_start;
next_iter_range_start = U64_MAX;
ret = bch2_gc_walk_dirents(c, &links,
this_iter_range_start,
&next_iter_range_start);
if (ret)
break;
ret = bch2_gc_walk_inodes(c, lostfound_inode, &links,
this_iter_range_start,
next_iter_range_start);
if (ret)
break;
genradix_free(&links);
} while (next_iter_range_start != U64_MAX);
genradix_free(&links);
return ret;
}
/*
* Checks for inconsistencies that shouldn't happen, unless we have a bug.
* Doesn't fix them yet, mainly because they haven't yet been observed:
*/
int bch2_fsck_full(struct bch_fs *c)
{
struct bch_inode_unpacked root_inode, lostfound_inode;
return check_extents(c) ?:
check_dirents(c) ?:
check_xattrs(c) ?:
check_root(c, &root_inode) ?:
check_lostfound(c, &root_inode, &lostfound_inode) ?:
check_directory_structure(c, &lostfound_inode) ?:
check_inode_nlinks(c, &lostfound_inode);
}
int bch2_fsck_inode_nlink(struct bch_fs *c)
{
struct bch_inode_unpacked root_inode, lostfound_inode;
return check_root(c, &root_inode) ?:
check_lostfound(c, &root_inode, &lostfound_inode) ?:
check_inode_nlinks(c, &lostfound_inode);
}
int bch2_fsck_walk_inodes_only(struct bch_fs *c)
{
struct btree_trans trans;
struct btree_iter *iter;
struct bkey_s_c k;
struct bkey_s_c_inode inode;
int ret;
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
for_each_btree_key(&trans, iter, BTREE_ID_INODES, POS_MIN, 0, k, ret) {
if (k.k->type != KEY_TYPE_inode)
continue;
inode = bkey_s_c_to_inode(k);
if (inode.v->bi_flags &
(BCH_INODE_I_SIZE_DIRTY|
BCH_INODE_I_SECTORS_DIRTY|
BCH_INODE_UNLINKED)) {
ret = check_inode(&trans, NULL, iter, inode, NULL);
BUG_ON(ret == -EINTR);
if (ret)
break;
}
}
BUG_ON(ret == -EINTR);
return bch2_trans_exit(&trans) ?: ret;
}