linux-stable/fs/ubifs/replay.c
Thomas Gleixner 2b27bdcc20 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 336
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 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 51 franklin st fifth floor boston ma 02110
  1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 246 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.674189849@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:07 +02:00

1267 lines
34 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* This file is part of UBIFS.
*
* Copyright (C) 2006-2008 Nokia Corporation.
*
* Authors: Adrian Hunter
* Artem Bityutskiy (Битюцкий Артём)
*/
/*
* This file contains journal replay code. It runs when the file-system is being
* mounted and requires no locking.
*
* The larger is the journal, the longer it takes to scan it, so the longer it
* takes to mount UBIFS. This is why the journal has limited size which may be
* changed depending on the system requirements. But a larger journal gives
* faster I/O speed because it writes the index less frequently. So this is a
* trade-off. Also, the journal is indexed by the in-memory index (TNC), so the
* larger is the journal, the more memory its index may consume.
*/
#include "ubifs.h"
#include <linux/list_sort.h>
#include <crypto/hash.h>
#include <crypto/algapi.h>
/**
* struct replay_entry - replay list entry.
* @lnum: logical eraseblock number of the node
* @offs: node offset
* @len: node length
* @deletion: non-zero if this entry corresponds to a node deletion
* @sqnum: node sequence number
* @list: links the replay list
* @key: node key
* @nm: directory entry name
* @old_size: truncation old size
* @new_size: truncation new size
*
* The replay process first scans all buds and builds the replay list, then
* sorts the replay list in nodes sequence number order, and then inserts all
* the replay entries to the TNC.
*/
struct replay_entry {
int lnum;
int offs;
int len;
u8 hash[UBIFS_HASH_ARR_SZ];
unsigned int deletion:1;
unsigned long long sqnum;
struct list_head list;
union ubifs_key key;
union {
struct fscrypt_name nm;
struct {
loff_t old_size;
loff_t new_size;
};
};
};
/**
* struct bud_entry - entry in the list of buds to replay.
* @list: next bud in the list
* @bud: bud description object
* @sqnum: reference node sequence number
* @free: free bytes in the bud
* @dirty: dirty bytes in the bud
*/
struct bud_entry {
struct list_head list;
struct ubifs_bud *bud;
unsigned long long sqnum;
int free;
int dirty;
};
/**
* set_bud_lprops - set free and dirty space used by a bud.
* @c: UBIFS file-system description object
* @b: bud entry which describes the bud
*
* This function makes sure the LEB properties of bud @b are set correctly
* after the replay. Returns zero in case of success and a negative error code
* in case of failure.
*/
static int set_bud_lprops(struct ubifs_info *c, struct bud_entry *b)
{
const struct ubifs_lprops *lp;
int err = 0, dirty;
ubifs_get_lprops(c);
lp = ubifs_lpt_lookup_dirty(c, b->bud->lnum);
if (IS_ERR(lp)) {
err = PTR_ERR(lp);
goto out;
}
dirty = lp->dirty;
if (b->bud->start == 0 && (lp->free != c->leb_size || lp->dirty != 0)) {
/*
* The LEB was added to the journal with a starting offset of
* zero which means the LEB must have been empty. The LEB
* property values should be @lp->free == @c->leb_size and
* @lp->dirty == 0, but that is not the case. The reason is that
* the LEB had been garbage collected before it became the bud,
* and there was not commit inbetween. The garbage collector
* resets the free and dirty space without recording it
* anywhere except lprops, so if there was no commit then
* lprops does not have that information.
*
* We do not need to adjust free space because the scan has told
* us the exact value which is recorded in the replay entry as
* @b->free.
*
* However we do need to subtract from the dirty space the
* amount of space that the garbage collector reclaimed, which
* is the whole LEB minus the amount of space that was free.
*/
dbg_mnt("bud LEB %d was GC'd (%d free, %d dirty)", b->bud->lnum,
lp->free, lp->dirty);
dbg_gc("bud LEB %d was GC'd (%d free, %d dirty)", b->bud->lnum,
lp->free, lp->dirty);
dirty -= c->leb_size - lp->free;
/*
* If the replay order was perfect the dirty space would now be
* zero. The order is not perfect because the journal heads
* race with each other. This is not a problem but is does mean
* that the dirty space may temporarily exceed c->leb_size
* during the replay.
*/
if (dirty != 0)
dbg_mnt("LEB %d lp: %d free %d dirty replay: %d free %d dirty",
b->bud->lnum, lp->free, lp->dirty, b->free,
b->dirty);
}
lp = ubifs_change_lp(c, lp, b->free, dirty + b->dirty,
lp->flags | LPROPS_TAKEN, 0);
if (IS_ERR(lp)) {
err = PTR_ERR(lp);
goto out;
}
/* Make sure the journal head points to the latest bud */
err = ubifs_wbuf_seek_nolock(&c->jheads[b->bud->jhead].wbuf,
b->bud->lnum, c->leb_size - b->free);
out:
ubifs_release_lprops(c);
return err;
}
/**
* set_buds_lprops - set free and dirty space for all replayed buds.
* @c: UBIFS file-system description object
*
* This function sets LEB properties for all replayed buds. Returns zero in
* case of success and a negative error code in case of failure.
*/
static int set_buds_lprops(struct ubifs_info *c)
{
struct bud_entry *b;
int err;
list_for_each_entry(b, &c->replay_buds, list) {
err = set_bud_lprops(c, b);
if (err)
return err;
}
return 0;
}
/**
* trun_remove_range - apply a replay entry for a truncation to the TNC.
* @c: UBIFS file-system description object
* @r: replay entry of truncation
*/
static int trun_remove_range(struct ubifs_info *c, struct replay_entry *r)
{
unsigned min_blk, max_blk;
union ubifs_key min_key, max_key;
ino_t ino;
min_blk = r->new_size / UBIFS_BLOCK_SIZE;
if (r->new_size & (UBIFS_BLOCK_SIZE - 1))
min_blk += 1;
max_blk = r->old_size / UBIFS_BLOCK_SIZE;
if ((r->old_size & (UBIFS_BLOCK_SIZE - 1)) == 0)
max_blk -= 1;
ino = key_inum(c, &r->key);
data_key_init(c, &min_key, ino, min_blk);
data_key_init(c, &max_key, ino, max_blk);
return ubifs_tnc_remove_range(c, &min_key, &max_key);
}
/**
* inode_still_linked - check whether inode in question will be re-linked.
* @c: UBIFS file-system description object
* @rino: replay entry to test
*
* O_TMPFILE files can be re-linked, this means link count goes from 0 to 1.
* This case needs special care, otherwise all references to the inode will
* be removed upon the first replay entry of an inode with link count 0
* is found.
*/
static bool inode_still_linked(struct ubifs_info *c, struct replay_entry *rino)
{
struct replay_entry *r;
ubifs_assert(c, rino->deletion);
ubifs_assert(c, key_type(c, &rino->key) == UBIFS_INO_KEY);
/*
* Find the most recent entry for the inode behind @rino and check
* whether it is a deletion.
*/
list_for_each_entry_reverse(r, &c->replay_list, list) {
ubifs_assert(c, r->sqnum >= rino->sqnum);
if (key_inum(c, &r->key) == key_inum(c, &rino->key))
return r->deletion == 0;
}
ubifs_assert(c, 0);
return false;
}
/**
* apply_replay_entry - apply a replay entry to the TNC.
* @c: UBIFS file-system description object
* @r: replay entry to apply
*
* Apply a replay entry to the TNC.
*/
static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
{
int err;
dbg_mntk(&r->key, "LEB %d:%d len %d deletion %d sqnum %llu key ",
r->lnum, r->offs, r->len, r->deletion, r->sqnum);
if (is_hash_key(c, &r->key)) {
if (r->deletion)
err = ubifs_tnc_remove_nm(c, &r->key, &r->nm);
else
err = ubifs_tnc_add_nm(c, &r->key, r->lnum, r->offs,
r->len, r->hash, &r->nm);
} else {
if (r->deletion)
switch (key_type(c, &r->key)) {
case UBIFS_INO_KEY:
{
ino_t inum = key_inum(c, &r->key);
if (inode_still_linked(c, r)) {
err = 0;
break;
}
err = ubifs_tnc_remove_ino(c, inum);
break;
}
case UBIFS_TRUN_KEY:
err = trun_remove_range(c, r);
break;
default:
err = ubifs_tnc_remove(c, &r->key);
break;
}
else
err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs,
r->len, r->hash);
if (err)
return err;
if (c->need_recovery)
err = ubifs_recover_size_accum(c, &r->key, r->deletion,
r->new_size);
}
return err;
}
/**
* replay_entries_cmp - compare 2 replay entries.
* @priv: UBIFS file-system description object
* @a: first replay entry
* @b: second replay entry
*
* This is a comparios function for 'list_sort()' which compares 2 replay
* entries @a and @b by comparing their sequence numer. Returns %1 if @a has
* greater sequence number and %-1 otherwise.
*/
static int replay_entries_cmp(void *priv, struct list_head *a,
struct list_head *b)
{
struct ubifs_info *c = priv;
struct replay_entry *ra, *rb;
cond_resched();
if (a == b)
return 0;
ra = list_entry(a, struct replay_entry, list);
rb = list_entry(b, struct replay_entry, list);
ubifs_assert(c, ra->sqnum != rb->sqnum);
if (ra->sqnum > rb->sqnum)
return 1;
return -1;
}
/**
* apply_replay_list - apply the replay list to the TNC.
* @c: UBIFS file-system description object
*
* Apply all entries in the replay list to the TNC. Returns zero in case of
* success and a negative error code in case of failure.
*/
static int apply_replay_list(struct ubifs_info *c)
{
struct replay_entry *r;
int err;
list_sort(c, &c->replay_list, &replay_entries_cmp);
list_for_each_entry(r, &c->replay_list, list) {
cond_resched();
err = apply_replay_entry(c, r);
if (err)
return err;
}
return 0;
}
/**
* destroy_replay_list - destroy the replay.
* @c: UBIFS file-system description object
*
* Destroy the replay list.
*/
static void destroy_replay_list(struct ubifs_info *c)
{
struct replay_entry *r, *tmp;
list_for_each_entry_safe(r, tmp, &c->replay_list, list) {
if (is_hash_key(c, &r->key))
kfree(fname_name(&r->nm));
list_del(&r->list);
kfree(r);
}
}
/**
* insert_node - insert a node to the replay list
* @c: UBIFS file-system description object
* @lnum: node logical eraseblock number
* @offs: node offset
* @len: node length
* @key: node key
* @sqnum: sequence number
* @deletion: non-zero if this is a deletion
* @used: number of bytes in use in a LEB
* @old_size: truncation old size
* @new_size: truncation new size
*
* This function inserts a scanned non-direntry node to the replay list. The
* replay list contains @struct replay_entry elements, and we sort this list in
* sequence number order before applying it. The replay list is applied at the
* very end of the replay process. Since the list is sorted in sequence number
* order, the older modifications are applied first. This function returns zero
* in case of success and a negative error code in case of failure.
*/
static int insert_node(struct ubifs_info *c, int lnum, int offs, int len,
const u8 *hash, union ubifs_key *key,
unsigned long long sqnum, int deletion, int *used,
loff_t old_size, loff_t new_size)
{
struct replay_entry *r;
dbg_mntk(key, "add LEB %d:%d, key ", lnum, offs);
if (key_inum(c, key) >= c->highest_inum)
c->highest_inum = key_inum(c, key);
r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
if (!r)
return -ENOMEM;
if (!deletion)
*used += ALIGN(len, 8);
r->lnum = lnum;
r->offs = offs;
r->len = len;
ubifs_copy_hash(c, hash, r->hash);
r->deletion = !!deletion;
r->sqnum = sqnum;
key_copy(c, key, &r->key);
r->old_size = old_size;
r->new_size = new_size;
list_add_tail(&r->list, &c->replay_list);
return 0;
}
/**
* insert_dent - insert a directory entry node into the replay list.
* @c: UBIFS file-system description object
* @lnum: node logical eraseblock number
* @offs: node offset
* @len: node length
* @key: node key
* @name: directory entry name
* @nlen: directory entry name length
* @sqnum: sequence number
* @deletion: non-zero if this is a deletion
* @used: number of bytes in use in a LEB
*
* This function inserts a scanned directory entry node or an extended
* attribute entry to the replay list. Returns zero in case of success and a
* negative error code in case of failure.
*/
static int insert_dent(struct ubifs_info *c, int lnum, int offs, int len,
const u8 *hash, union ubifs_key *key,
const char *name, int nlen, unsigned long long sqnum,
int deletion, int *used)
{
struct replay_entry *r;
char *nbuf;
dbg_mntk(key, "add LEB %d:%d, key ", lnum, offs);
if (key_inum(c, key) >= c->highest_inum)
c->highest_inum = key_inum(c, key);
r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
if (!r)
return -ENOMEM;
nbuf = kmalloc(nlen + 1, GFP_KERNEL);
if (!nbuf) {
kfree(r);
return -ENOMEM;
}
if (!deletion)
*used += ALIGN(len, 8);
r->lnum = lnum;
r->offs = offs;
r->len = len;
ubifs_copy_hash(c, hash, r->hash);
r->deletion = !!deletion;
r->sqnum = sqnum;
key_copy(c, key, &r->key);
fname_len(&r->nm) = nlen;
memcpy(nbuf, name, nlen);
nbuf[nlen] = '\0';
fname_name(&r->nm) = nbuf;
list_add_tail(&r->list, &c->replay_list);
return 0;
}
/**
* ubifs_validate_entry - validate directory or extended attribute entry node.
* @c: UBIFS file-system description object
* @dent: the node to validate
*
* This function validates directory or extended attribute entry node @dent.
* Returns zero if the node is all right and a %-EINVAL if not.
*/
int ubifs_validate_entry(struct ubifs_info *c,
const struct ubifs_dent_node *dent)
{
int key_type = key_type_flash(c, dent->key);
int nlen = le16_to_cpu(dent->nlen);
if (le32_to_cpu(dent->ch.len) != nlen + UBIFS_DENT_NODE_SZ + 1 ||
dent->type >= UBIFS_ITYPES_CNT ||
nlen > UBIFS_MAX_NLEN || dent->name[nlen] != 0 ||
(key_type == UBIFS_XENT_KEY && strnlen(dent->name, nlen) != nlen) ||
le64_to_cpu(dent->inum) > MAX_INUM) {
ubifs_err(c, "bad %s node", key_type == UBIFS_DENT_KEY ?
"directory entry" : "extended attribute entry");
return -EINVAL;
}
if (key_type != UBIFS_DENT_KEY && key_type != UBIFS_XENT_KEY) {
ubifs_err(c, "bad key type %d", key_type);
return -EINVAL;
}
return 0;
}
/**
* is_last_bud - check if the bud is the last in the journal head.
* @c: UBIFS file-system description object
* @bud: bud description object
*
* This function checks if bud @bud is the last bud in its journal head. This
* information is then used by 'replay_bud()' to decide whether the bud can
* have corruptions or not. Indeed, only last buds can be corrupted by power
* cuts. Returns %1 if this is the last bud, and %0 if not.
*/
static int is_last_bud(struct ubifs_info *c, struct ubifs_bud *bud)
{
struct ubifs_jhead *jh = &c->jheads[bud->jhead];
struct ubifs_bud *next;
uint32_t data;
int err;
if (list_is_last(&bud->list, &jh->buds_list))
return 1;
/*
* The following is a quirk to make sure we work correctly with UBIFS
* images used with older UBIFS.
*
* Normally, the last bud will be the last in the journal head's list
* of bud. However, there is one exception if the UBIFS image belongs
* to older UBIFS. This is fairly unlikely: one would need to use old
* UBIFS, then have a power cut exactly at the right point, and then
* try to mount this image with new UBIFS.
*
* The exception is: it is possible to have 2 buds A and B, A goes
* before B, and B is the last, bud B is contains no data, and bud A is
* corrupted at the end. The reason is that in older versions when the
* journal code switched the next bud (from A to B), it first added a
* log reference node for the new bud (B), and only after this it
* synchronized the write-buffer of current bud (A). But later this was
* changed and UBIFS started to always synchronize the write-buffer of
* the bud (A) before writing the log reference for the new bud (B).
*
* But because older UBIFS always synchronized A's write-buffer before
* writing to B, we can recognize this exceptional situation but
* checking the contents of bud B - if it is empty, then A can be
* treated as the last and we can recover it.
*
* TODO: remove this piece of code in a couple of years (today it is
* 16.05.2011).
*/
next = list_entry(bud->list.next, struct ubifs_bud, list);
if (!list_is_last(&next->list, &jh->buds_list))
return 0;
err = ubifs_leb_read(c, next->lnum, (char *)&data, next->start, 4, 1);
if (err)
return 0;
return data == 0xFFFFFFFF;
}
/* authenticate_sleb_hash and authenticate_sleb_hmac are split out for stack usage */
static int authenticate_sleb_hash(struct ubifs_info *c, struct shash_desc *log_hash, u8 *hash)
{
SHASH_DESC_ON_STACK(hash_desc, c->hash_tfm);
hash_desc->tfm = c->hash_tfm;
ubifs_shash_copy_state(c, log_hash, hash_desc);
return crypto_shash_final(hash_desc, hash);
}
static int authenticate_sleb_hmac(struct ubifs_info *c, u8 *hash, u8 *hmac)
{
SHASH_DESC_ON_STACK(hmac_desc, c->hmac_tfm);
hmac_desc->tfm = c->hmac_tfm;
return crypto_shash_digest(hmac_desc, hash, c->hash_len, hmac);
}
/**
* authenticate_sleb - authenticate one scan LEB
* @c: UBIFS file-system description object
* @sleb: the scan LEB to authenticate
* @log_hash:
* @is_last: if true, this is is the last LEB
*
* This function iterates over the buds of a single LEB authenticating all buds
* with the authentication nodes on this LEB. Authentication nodes are written
* after some buds and contain a HMAC covering the authentication node itself
* and the buds between the last authentication node and the current
* authentication node. It can happen that the last buds cannot be authenticated
* because a powercut happened when some nodes were written but not the
* corresponding authentication node. This function returns the number of nodes
* that could be authenticated or a negative error code.
*/
static int authenticate_sleb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
struct shash_desc *log_hash, int is_last)
{
int n_not_auth = 0;
struct ubifs_scan_node *snod;
int n_nodes = 0;
int err;
u8 *hash, *hmac;
if (!ubifs_authenticated(c))
return sleb->nodes_cnt;
hash = kmalloc(crypto_shash_descsize(c->hash_tfm), GFP_NOFS);
hmac = kmalloc(c->hmac_desc_len, GFP_NOFS);
if (!hash || !hmac) {
err = -ENOMEM;
goto out;
}
list_for_each_entry(snod, &sleb->nodes, list) {
n_nodes++;
if (snod->type == UBIFS_AUTH_NODE) {
struct ubifs_auth_node *auth = snod->node;
err = authenticate_sleb_hash(c, log_hash, hash);
if (err)
goto out;
err = authenticate_sleb_hmac(c, hash, hmac);
if (err)
goto out;
err = ubifs_check_hmac(c, auth->hmac, hmac);
if (err) {
err = -EPERM;
goto out;
}
n_not_auth = 0;
} else {
err = crypto_shash_update(log_hash, snod->node,
snod->len);
if (err)
goto out;
n_not_auth++;
}
}
/*
* A powercut can happen when some nodes were written, but not yet
* the corresponding authentication node. This may only happen on
* the last bud though.
*/
if (n_not_auth) {
if (is_last) {
dbg_mnt("%d unauthenticated nodes found on LEB %d, Ignoring them",
n_not_auth, sleb->lnum);
err = 0;
} else {
dbg_mnt("%d unauthenticated nodes found on non-last LEB %d",
n_not_auth, sleb->lnum);
err = -EPERM;
}
} else {
err = 0;
}
out:
kfree(hash);
kfree(hmac);
return err ? err : n_nodes - n_not_auth;
}
/**
* replay_bud - replay a bud logical eraseblock.
* @c: UBIFS file-system description object
* @b: bud entry which describes the bud
*
* This function replays bud @bud, recovers it if needed, and adds all nodes
* from this bud to the replay list. Returns zero in case of success and a
* negative error code in case of failure.
*/
static int replay_bud(struct ubifs_info *c, struct bud_entry *b)
{
int is_last = is_last_bud(c, b->bud);
int err = 0, used = 0, lnum = b->bud->lnum, offs = b->bud->start;
int n_nodes, n = 0;
struct ubifs_scan_leb *sleb;
struct ubifs_scan_node *snod;
dbg_mnt("replay bud LEB %d, head %d, offs %d, is_last %d",
lnum, b->bud->jhead, offs, is_last);
if (c->need_recovery && is_last)
/*
* Recover only last LEBs in the journal heads, because power
* cuts may cause corruptions only in these LEBs, because only
* these LEBs could possibly be written to at the power cut
* time.
*/
sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, b->bud->jhead);
else
sleb = ubifs_scan(c, lnum, offs, c->sbuf, 0);
if (IS_ERR(sleb))
return PTR_ERR(sleb);
n_nodes = authenticate_sleb(c, sleb, b->bud->log_hash, is_last);
if (n_nodes < 0) {
err = n_nodes;
goto out;
}
ubifs_shash_copy_state(c, b->bud->log_hash,
c->jheads[b->bud->jhead].log_hash);
/*
* The bud does not have to start from offset zero - the beginning of
* the 'lnum' LEB may contain previously committed data. One of the
* things we have to do in replay is to correctly update lprops with
* newer information about this LEB.
*
* At this point lprops thinks that this LEB has 'c->leb_size - offs'
* bytes of free space because it only contain information about
* committed data.
*
* But we know that real amount of free space is 'c->leb_size -
* sleb->endpt', and the space in the 'lnum' LEB between 'offs' and
* 'sleb->endpt' is used by bud data. We have to correctly calculate
* how much of these data are dirty and update lprops with this
* information.
*
* The dirt in that LEB region is comprised of padding nodes, deletion
* nodes, truncation nodes and nodes which are obsoleted by subsequent
* nodes in this LEB. So instead of calculating clean space, we
* calculate used space ('used' variable).
*/
list_for_each_entry(snod, &sleb->nodes, list) {
u8 hash[UBIFS_HASH_ARR_SZ];
int deletion = 0;
cond_resched();
if (snod->sqnum >= SQNUM_WATERMARK) {
ubifs_err(c, "file system's life ended");
goto out_dump;
}
ubifs_node_calc_hash(c, snod->node, hash);
if (snod->sqnum > c->max_sqnum)
c->max_sqnum = snod->sqnum;
switch (snod->type) {
case UBIFS_INO_NODE:
{
struct ubifs_ino_node *ino = snod->node;
loff_t new_size = le64_to_cpu(ino->size);
if (le32_to_cpu(ino->nlink) == 0)
deletion = 1;
err = insert_node(c, lnum, snod->offs, snod->len, hash,
&snod->key, snod->sqnum, deletion,
&used, 0, new_size);
break;
}
case UBIFS_DATA_NODE:
{
struct ubifs_data_node *dn = snod->node;
loff_t new_size = le32_to_cpu(dn->size) +
key_block(c, &snod->key) *
UBIFS_BLOCK_SIZE;
err = insert_node(c, lnum, snod->offs, snod->len, hash,
&snod->key, snod->sqnum, deletion,
&used, 0, new_size);
break;
}
case UBIFS_DENT_NODE:
case UBIFS_XENT_NODE:
{
struct ubifs_dent_node *dent = snod->node;
err = ubifs_validate_entry(c, dent);
if (err)
goto out_dump;
err = insert_dent(c, lnum, snod->offs, snod->len, hash,
&snod->key, dent->name,
le16_to_cpu(dent->nlen), snod->sqnum,
!le64_to_cpu(dent->inum), &used);
break;
}
case UBIFS_TRUN_NODE:
{
struct ubifs_trun_node *trun = snod->node;
loff_t old_size = le64_to_cpu(trun->old_size);
loff_t new_size = le64_to_cpu(trun->new_size);
union ubifs_key key;
/* Validate truncation node */
if (old_size < 0 || old_size > c->max_inode_sz ||
new_size < 0 || new_size > c->max_inode_sz ||
old_size <= new_size) {
ubifs_err(c, "bad truncation node");
goto out_dump;
}
/*
* Create a fake truncation key just to use the same
* functions which expect nodes to have keys.
*/
trun_key_init(c, &key, le32_to_cpu(trun->inum));
err = insert_node(c, lnum, snod->offs, snod->len, hash,
&key, snod->sqnum, 1, &used,
old_size, new_size);
break;
}
case UBIFS_AUTH_NODE:
break;
default:
ubifs_err(c, "unexpected node type %d in bud LEB %d:%d",
snod->type, lnum, snod->offs);
err = -EINVAL;
goto out_dump;
}
if (err)
goto out;
n++;
if (n == n_nodes)
break;
}
ubifs_assert(c, ubifs_search_bud(c, lnum));
ubifs_assert(c, sleb->endpt - offs >= used);
ubifs_assert(c, sleb->endpt % c->min_io_size == 0);
b->dirty = sleb->endpt - offs - used;
b->free = c->leb_size - sleb->endpt;
dbg_mnt("bud LEB %d replied: dirty %d, free %d",
lnum, b->dirty, b->free);
out:
ubifs_scan_destroy(sleb);
return err;
out_dump:
ubifs_err(c, "bad node is at LEB %d:%d", lnum, snod->offs);
ubifs_dump_node(c, snod->node);
ubifs_scan_destroy(sleb);
return -EINVAL;
}
/**
* replay_buds - replay all buds.
* @c: UBIFS file-system description object
*
* This function returns zero in case of success and a negative error code in
* case of failure.
*/
static int replay_buds(struct ubifs_info *c)
{
struct bud_entry *b;
int err;
unsigned long long prev_sqnum = 0;
list_for_each_entry(b, &c->replay_buds, list) {
err = replay_bud(c, b);
if (err)
return err;
ubifs_assert(c, b->sqnum > prev_sqnum);
prev_sqnum = b->sqnum;
}
return 0;
}
/**
* destroy_bud_list - destroy the list of buds to replay.
* @c: UBIFS file-system description object
*/
static void destroy_bud_list(struct ubifs_info *c)
{
struct bud_entry *b;
while (!list_empty(&c->replay_buds)) {
b = list_entry(c->replay_buds.next, struct bud_entry, list);
list_del(&b->list);
kfree(b);
}
}
/**
* add_replay_bud - add a bud to the list of buds to replay.
* @c: UBIFS file-system description object
* @lnum: bud logical eraseblock number to replay
* @offs: bud start offset
* @jhead: journal head to which this bud belongs
* @sqnum: reference node sequence number
*
* This function returns zero in case of success and a negative error code in
* case of failure.
*/
static int add_replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
unsigned long long sqnum)
{
struct ubifs_bud *bud;
struct bud_entry *b;
int err;
dbg_mnt("add replay bud LEB %d:%d, head %d", lnum, offs, jhead);
bud = kmalloc(sizeof(struct ubifs_bud), GFP_KERNEL);
if (!bud)
return -ENOMEM;
b = kmalloc(sizeof(struct bud_entry), GFP_KERNEL);
if (!b) {
err = -ENOMEM;
goto out;
}
bud->lnum = lnum;
bud->start = offs;
bud->jhead = jhead;
bud->log_hash = ubifs_hash_get_desc(c);
if (IS_ERR(bud->log_hash)) {
err = PTR_ERR(bud->log_hash);
goto out;
}
ubifs_shash_copy_state(c, c->log_hash, bud->log_hash);
ubifs_add_bud(c, bud);
b->bud = bud;
b->sqnum = sqnum;
list_add_tail(&b->list, &c->replay_buds);
return 0;
out:
kfree(bud);
kfree(b);
return err;
}
/**
* validate_ref - validate a reference node.
* @c: UBIFS file-system description object
* @ref: the reference node to validate
* @ref_lnum: LEB number of the reference node
* @ref_offs: reference node offset
*
* This function returns %1 if a bud reference already exists for the LEB. %0 is
* returned if the reference node is new, otherwise %-EINVAL is returned if
* validation failed.
*/
static int validate_ref(struct ubifs_info *c, const struct ubifs_ref_node *ref)
{
struct ubifs_bud *bud;
int lnum = le32_to_cpu(ref->lnum);
unsigned int offs = le32_to_cpu(ref->offs);
unsigned int jhead = le32_to_cpu(ref->jhead);
/*
* ref->offs may point to the end of LEB when the journal head points
* to the end of LEB and we write reference node for it during commit.
* So this is why we require 'offs > c->leb_size'.
*/
if (jhead >= c->jhead_cnt || lnum >= c->leb_cnt ||
lnum < c->main_first || offs > c->leb_size ||
offs & (c->min_io_size - 1))
return -EINVAL;
/* Make sure we have not already looked at this bud */
bud = ubifs_search_bud(c, lnum);
if (bud) {
if (bud->jhead == jhead && bud->start <= offs)
return 1;
ubifs_err(c, "bud at LEB %d:%d was already referred", lnum, offs);
return -EINVAL;
}
return 0;
}
/**
* replay_log_leb - replay a log logical eraseblock.
* @c: UBIFS file-system description object
* @lnum: log logical eraseblock to replay
* @offs: offset to start replaying from
* @sbuf: scan buffer
*
* This function replays a log LEB and returns zero in case of success, %1 if
* this is the last LEB in the log, and a negative error code in case of
* failure.
*/
static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf)
{
int err;
struct ubifs_scan_leb *sleb;
struct ubifs_scan_node *snod;
const struct ubifs_cs_node *node;
dbg_mnt("replay log LEB %d:%d", lnum, offs);
sleb = ubifs_scan(c, lnum, offs, sbuf, c->need_recovery);
if (IS_ERR(sleb)) {
if (PTR_ERR(sleb) != -EUCLEAN || !c->need_recovery)
return PTR_ERR(sleb);
/*
* Note, the below function will recover this log LEB only if
* it is the last, because unclean reboots can possibly corrupt
* only the tail of the log.
*/
sleb = ubifs_recover_log_leb(c, lnum, offs, sbuf);
if (IS_ERR(sleb))
return PTR_ERR(sleb);
}
if (sleb->nodes_cnt == 0) {
err = 1;
goto out;
}
node = sleb->buf;
snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
if (c->cs_sqnum == 0) {
/*
* This is the first log LEB we are looking at, make sure that
* the first node is a commit start node. Also record its
* sequence number so that UBIFS can determine where the log
* ends, because all nodes which were have higher sequence
* numbers.
*/
if (snod->type != UBIFS_CS_NODE) {
ubifs_err(c, "first log node at LEB %d:%d is not CS node",
lnum, offs);
goto out_dump;
}
if (le64_to_cpu(node->cmt_no) != c->cmt_no) {
ubifs_err(c, "first CS node at LEB %d:%d has wrong commit number %llu expected %llu",
lnum, offs,
(unsigned long long)le64_to_cpu(node->cmt_no),
c->cmt_no);
goto out_dump;
}
c->cs_sqnum = le64_to_cpu(node->ch.sqnum);
dbg_mnt("commit start sqnum %llu", c->cs_sqnum);
err = ubifs_shash_init(c, c->log_hash);
if (err)
goto out;
err = ubifs_shash_update(c, c->log_hash, node, UBIFS_CS_NODE_SZ);
if (err < 0)
goto out;
}
if (snod->sqnum < c->cs_sqnum) {
/*
* This means that we reached end of log and now
* look to the older log data, which was already
* committed but the eraseblock was not erased (UBIFS
* only un-maps it). So this basically means we have to
* exit with "end of log" code.
*/
err = 1;
goto out;
}
/* Make sure the first node sits at offset zero of the LEB */
if (snod->offs != 0) {
ubifs_err(c, "first node is not at zero offset");
goto out_dump;
}
list_for_each_entry(snod, &sleb->nodes, list) {
cond_resched();
if (snod->sqnum >= SQNUM_WATERMARK) {
ubifs_err(c, "file system's life ended");
goto out_dump;
}
if (snod->sqnum < c->cs_sqnum) {
ubifs_err(c, "bad sqnum %llu, commit sqnum %llu",
snod->sqnum, c->cs_sqnum);
goto out_dump;
}
if (snod->sqnum > c->max_sqnum)
c->max_sqnum = snod->sqnum;
switch (snod->type) {
case UBIFS_REF_NODE: {
const struct ubifs_ref_node *ref = snod->node;
err = validate_ref(c, ref);
if (err == 1)
break; /* Already have this bud */
if (err)
goto out_dump;
err = ubifs_shash_update(c, c->log_hash, ref,
UBIFS_REF_NODE_SZ);
if (err)
goto out;
err = add_replay_bud(c, le32_to_cpu(ref->lnum),
le32_to_cpu(ref->offs),
le32_to_cpu(ref->jhead),
snod->sqnum);
if (err)
goto out;
break;
}
case UBIFS_CS_NODE:
/* Make sure it sits at the beginning of LEB */
if (snod->offs != 0) {
ubifs_err(c, "unexpected node in log");
goto out_dump;
}
break;
default:
ubifs_err(c, "unexpected node in log");
goto out_dump;
}
}
if (sleb->endpt || c->lhead_offs >= c->leb_size) {
c->lhead_lnum = lnum;
c->lhead_offs = sleb->endpt;
}
err = !sleb->endpt;
out:
ubifs_scan_destroy(sleb);
return err;
out_dump:
ubifs_err(c, "log error detected while replaying the log at LEB %d:%d",
lnum, offs + snod->offs);
ubifs_dump_node(c, snod->node);
ubifs_scan_destroy(sleb);
return -EINVAL;
}
/**
* take_ihead - update the status of the index head in lprops to 'taken'.
* @c: UBIFS file-system description object
*
* This function returns the amount of free space in the index head LEB or a
* negative error code.
*/
static int take_ihead(struct ubifs_info *c)
{
const struct ubifs_lprops *lp;
int err, free;
ubifs_get_lprops(c);
lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum);
if (IS_ERR(lp)) {
err = PTR_ERR(lp);
goto out;
}
free = lp->free;
lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
lp->flags | LPROPS_TAKEN, 0);
if (IS_ERR(lp)) {
err = PTR_ERR(lp);
goto out;
}
err = free;
out:
ubifs_release_lprops(c);
return err;
}
/**
* ubifs_replay_journal - replay journal.
* @c: UBIFS file-system description object
*
* This function scans the journal, replays and cleans it up. It makes sure all
* memory data structures related to uncommitted journal are built (dirty TNC
* tree, tree of buds, modified lprops, etc).
*/
int ubifs_replay_journal(struct ubifs_info *c)
{
int err, lnum, free;
BUILD_BUG_ON(UBIFS_TRUN_KEY > 5);
/* Update the status of the index head in lprops to 'taken' */
free = take_ihead(c);
if (free < 0)
return free; /* Error code */
if (c->ihead_offs != c->leb_size - free) {
ubifs_err(c, "bad index head LEB %d:%d", c->ihead_lnum,
c->ihead_offs);
return -EINVAL;
}
dbg_mnt("start replaying the journal");
c->replaying = 1;
lnum = c->ltail_lnum = c->lhead_lnum;
do {
err = replay_log_leb(c, lnum, 0, c->sbuf);
if (err == 1) {
if (lnum != c->lhead_lnum)
/* We hit the end of the log */
break;
/*
* The head of the log must always start with the
* "commit start" node on a properly formatted UBIFS.
* But we found no nodes at all, which means that
* something went wrong and we cannot proceed mounting
* the file-system.
*/
ubifs_err(c, "no UBIFS nodes found at the log head LEB %d:%d, possibly corrupted",
lnum, 0);
err = -EINVAL;
}
if (err)
goto out;
lnum = ubifs_next_log_lnum(c, lnum);
} while (lnum != c->ltail_lnum);
err = replay_buds(c);
if (err)
goto out;
err = apply_replay_list(c);
if (err)
goto out;
err = set_buds_lprops(c);
if (err)
goto out;
/*
* UBIFS budgeting calculations use @c->bi.uncommitted_idx variable
* to roughly estimate index growth. Things like @c->bi.min_idx_lebs
* depend on it. This means we have to initialize it to make sure
* budgeting works properly.
*/
c->bi.uncommitted_idx = atomic_long_read(&c->dirty_zn_cnt);
c->bi.uncommitted_idx *= c->max_idx_node_sz;
ubifs_assert(c, c->bud_bytes <= c->max_bud_bytes || c->need_recovery);
dbg_mnt("finished, log head LEB %d:%d, max_sqnum %llu, highest_inum %lu",
c->lhead_lnum, c->lhead_offs, c->max_sqnum,
(unsigned long)c->highest_inum);
out:
destroy_replay_list(c);
destroy_bud_list(c);
c->replaying = 0;
return err;
}