linux/fs/ubifs/orphan.c
Zhihao Cheng a33e30a0e0 ubifs: Pass node length in all node dumping callers
Function ubifs_dump_node() has been modified to avoid memory oob
accessing while dumping node, node length (corresponding to the
size of allocated memory for node) should be passed into all node
dumping callers.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2020-12-13 22:12:32 +01:00

1053 lines
26 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* This file is part of UBIFS.
*
* Copyright (C) 2006-2008 Nokia Corporation.
*
* Author: Adrian Hunter
*/
#include "ubifs.h"
/*
* An orphan is an inode number whose inode node has been committed to the index
* with a link count of zero. That happens when an open file is deleted
* (unlinked) and then a commit is run. In the normal course of events the inode
* would be deleted when the file is closed. However in the case of an unclean
* unmount, orphans need to be accounted for. After an unclean unmount, the
* orphans' inodes must be deleted which means either scanning the entire index
* looking for them, or keeping a list on flash somewhere. This unit implements
* the latter approach.
*
* The orphan area is a fixed number of LEBs situated between the LPT area and
* the main area. The number of orphan area LEBs is specified when the file
* system is created. The minimum number is 1. The size of the orphan area
* should be so that it can hold the maximum number of orphans that are expected
* to ever exist at one time.
*
* The number of orphans that can fit in a LEB is:
*
* (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)
*
* For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough.
*
* Orphans are accumulated in a rb-tree. When an inode's link count drops to
* zero, the inode number is added to the rb-tree. It is removed from the tree
* when the inode is deleted. Any new orphans that are in the orphan tree when
* the commit is run, are written to the orphan area in 1 or more orphan nodes.
* If the orphan area is full, it is consolidated to make space. There is
* always enough space because validation prevents the user from creating more
* than the maximum number of orphans allowed.
*/
static int dbg_check_orphans(struct ubifs_info *c);
static struct ubifs_orphan *orphan_add(struct ubifs_info *c, ino_t inum,
struct ubifs_orphan *parent_orphan)
{
struct ubifs_orphan *orphan, *o;
struct rb_node **p, *parent = NULL;
orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_NOFS);
if (!orphan)
return ERR_PTR(-ENOMEM);
orphan->inum = inum;
orphan->new = 1;
INIT_LIST_HEAD(&orphan->child_list);
spin_lock(&c->orphan_lock);
if (c->tot_orphans >= c->max_orphans) {
spin_unlock(&c->orphan_lock);
kfree(orphan);
return ERR_PTR(-ENFILE);
}
p = &c->orph_tree.rb_node;
while (*p) {
parent = *p;
o = rb_entry(parent, struct ubifs_orphan, rb);
if (inum < o->inum)
p = &(*p)->rb_left;
else if (inum > o->inum)
p = &(*p)->rb_right;
else {
ubifs_err(c, "orphaned twice");
spin_unlock(&c->orphan_lock);
kfree(orphan);
return ERR_PTR(-EINVAL);
}
}
c->tot_orphans += 1;
c->new_orphans += 1;
rb_link_node(&orphan->rb, parent, p);
rb_insert_color(&orphan->rb, &c->orph_tree);
list_add_tail(&orphan->list, &c->orph_list);
list_add_tail(&orphan->new_list, &c->orph_new);
if (parent_orphan) {
list_add_tail(&orphan->child_list,
&parent_orphan->child_list);
}
spin_unlock(&c->orphan_lock);
dbg_gen("ino %lu", (unsigned long)inum);
return orphan;
}
static struct ubifs_orphan *lookup_orphan(struct ubifs_info *c, ino_t inum)
{
struct ubifs_orphan *o;
struct rb_node *p;
p = c->orph_tree.rb_node;
while (p) {
o = rb_entry(p, struct ubifs_orphan, rb);
if (inum < o->inum)
p = p->rb_left;
else if (inum > o->inum)
p = p->rb_right;
else {
return o;
}
}
return NULL;
}
static void __orphan_drop(struct ubifs_info *c, struct ubifs_orphan *o)
{
rb_erase(&o->rb, &c->orph_tree);
list_del(&o->list);
c->tot_orphans -= 1;
if (o->new) {
list_del(&o->new_list);
c->new_orphans -= 1;
}
kfree(o);
}
static void orphan_delete(struct ubifs_info *c, struct ubifs_orphan *orph)
{
if (orph->del) {
dbg_gen("deleted twice ino %lu", (unsigned long)orph->inum);
return;
}
if (orph->cmt) {
orph->del = 1;
orph->dnext = c->orph_dnext;
c->orph_dnext = orph;
dbg_gen("delete later ino %lu", (unsigned long)orph->inum);
return;
}
__orphan_drop(c, orph);
}
/**
* ubifs_add_orphan - add an orphan.
* @c: UBIFS file-system description object
* @inum: orphan inode number
*
* Add an orphan. This function is called when an inodes link count drops to
* zero.
*/
int ubifs_add_orphan(struct ubifs_info *c, ino_t inum)
{
int err = 0;
ino_t xattr_inum;
union ubifs_key key;
struct ubifs_dent_node *xent, *pxent = NULL;
struct fscrypt_name nm = {0};
struct ubifs_orphan *xattr_orphan;
struct ubifs_orphan *orphan;
orphan = orphan_add(c, inum, NULL);
if (IS_ERR(orphan))
return PTR_ERR(orphan);
lowest_xent_key(c, &key, inum);
while (1) {
xent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(xent)) {
err = PTR_ERR(xent);
if (err == -ENOENT)
break;
kfree(pxent);
return err;
}
fname_name(&nm) = xent->name;
fname_len(&nm) = le16_to_cpu(xent->nlen);
xattr_inum = le64_to_cpu(xent->inum);
xattr_orphan = orphan_add(c, xattr_inum, orphan);
if (IS_ERR(xattr_orphan)) {
kfree(pxent);
kfree(xent);
return PTR_ERR(xattr_orphan);
}
kfree(pxent);
pxent = xent;
key_read(c, &xent->key, &key);
}
kfree(pxent);
return 0;
}
/**
* ubifs_delete_orphan - delete an orphan.
* @c: UBIFS file-system description object
* @inum: orphan inode number
*
* Delete an orphan. This function is called when an inode is deleted.
*/
void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum)
{
struct ubifs_orphan *orph, *child_orph, *tmp_o;
spin_lock(&c->orphan_lock);
orph = lookup_orphan(c, inum);
if (!orph) {
spin_unlock(&c->orphan_lock);
ubifs_err(c, "missing orphan ino %lu", (unsigned long)inum);
dump_stack();
return;
}
list_for_each_entry_safe(child_orph, tmp_o, &orph->child_list, child_list) {
list_del(&child_orph->child_list);
orphan_delete(c, child_orph);
}
orphan_delete(c, orph);
spin_unlock(&c->orphan_lock);
}
/**
* ubifs_orphan_start_commit - start commit of orphans.
* @c: UBIFS file-system description object
*
* Start commit of orphans.
*/
int ubifs_orphan_start_commit(struct ubifs_info *c)
{
struct ubifs_orphan *orphan, **last;
spin_lock(&c->orphan_lock);
last = &c->orph_cnext;
list_for_each_entry(orphan, &c->orph_new, new_list) {
ubifs_assert(c, orphan->new);
ubifs_assert(c, !orphan->cmt);
orphan->new = 0;
orphan->cmt = 1;
*last = orphan;
last = &orphan->cnext;
}
*last = NULL;
c->cmt_orphans = c->new_orphans;
c->new_orphans = 0;
dbg_cmt("%d orphans to commit", c->cmt_orphans);
INIT_LIST_HEAD(&c->orph_new);
if (c->tot_orphans == 0)
c->no_orphs = 1;
else
c->no_orphs = 0;
spin_unlock(&c->orphan_lock);
return 0;
}
/**
* avail_orphs - calculate available space.
* @c: UBIFS file-system description object
*
* This function returns the number of orphans that can be written in the
* available space.
*/
static int avail_orphs(struct ubifs_info *c)
{
int avail_lebs, avail, gap;
avail_lebs = c->orph_lebs - (c->ohead_lnum - c->orph_first) - 1;
avail = avail_lebs *
((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
gap = c->leb_size - c->ohead_offs;
if (gap >= UBIFS_ORPH_NODE_SZ + sizeof(__le64))
avail += (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);
return avail;
}
/**
* tot_avail_orphs - calculate total space.
* @c: UBIFS file-system description object
*
* This function returns the number of orphans that can be written in half
* the total space. That leaves half the space for adding new orphans.
*/
static int tot_avail_orphs(struct ubifs_info *c)
{
int avail_lebs, avail;
avail_lebs = c->orph_lebs;
avail = avail_lebs *
((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
return avail / 2;
}
/**
* do_write_orph_node - write a node to the orphan head.
* @c: UBIFS file-system description object
* @len: length of node
* @atomic: write atomically
*
* This function writes a node to the orphan head from the orphan buffer. If
* %atomic is not zero, then the write is done atomically. On success, %0 is
* returned, otherwise a negative error code is returned.
*/
static int do_write_orph_node(struct ubifs_info *c, int len, int atomic)
{
int err = 0;
if (atomic) {
ubifs_assert(c, c->ohead_offs == 0);
ubifs_prepare_node(c, c->orph_buf, len, 1);
len = ALIGN(len, c->min_io_size);
err = ubifs_leb_change(c, c->ohead_lnum, c->orph_buf, len);
} else {
if (c->ohead_offs == 0) {
/* Ensure LEB has been unmapped */
err = ubifs_leb_unmap(c, c->ohead_lnum);
if (err)
return err;
}
err = ubifs_write_node(c, c->orph_buf, len, c->ohead_lnum,
c->ohead_offs);
}
return err;
}
/**
* write_orph_node - write an orphan node.
* @c: UBIFS file-system description object
* @atomic: write atomically
*
* This function builds an orphan node from the cnext list and writes it to the
* orphan head. On success, %0 is returned, otherwise a negative error code
* is returned.
*/
static int write_orph_node(struct ubifs_info *c, int atomic)
{
struct ubifs_orphan *orphan, *cnext;
struct ubifs_orph_node *orph;
int gap, err, len, cnt, i;
ubifs_assert(c, c->cmt_orphans > 0);
gap = c->leb_size - c->ohead_offs;
if (gap < UBIFS_ORPH_NODE_SZ + sizeof(__le64)) {
c->ohead_lnum += 1;
c->ohead_offs = 0;
gap = c->leb_size;
if (c->ohead_lnum > c->orph_last) {
/*
* We limit the number of orphans so that this should
* never happen.
*/
ubifs_err(c, "out of space in orphan area");
return -EINVAL;
}
}
cnt = (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);
if (cnt > c->cmt_orphans)
cnt = c->cmt_orphans;
len = UBIFS_ORPH_NODE_SZ + cnt * sizeof(__le64);
ubifs_assert(c, c->orph_buf);
orph = c->orph_buf;
orph->ch.node_type = UBIFS_ORPH_NODE;
spin_lock(&c->orphan_lock);
cnext = c->orph_cnext;
for (i = 0; i < cnt; i++) {
orphan = cnext;
ubifs_assert(c, orphan->cmt);
orph->inos[i] = cpu_to_le64(orphan->inum);
orphan->cmt = 0;
cnext = orphan->cnext;
orphan->cnext = NULL;
}
c->orph_cnext = cnext;
c->cmt_orphans -= cnt;
spin_unlock(&c->orphan_lock);
if (c->cmt_orphans)
orph->cmt_no = cpu_to_le64(c->cmt_no);
else
/* Mark the last node of the commit */
orph->cmt_no = cpu_to_le64((c->cmt_no) | (1ULL << 63));
ubifs_assert(c, c->ohead_offs + len <= c->leb_size);
ubifs_assert(c, c->ohead_lnum >= c->orph_first);
ubifs_assert(c, c->ohead_lnum <= c->orph_last);
err = do_write_orph_node(c, len, atomic);
c->ohead_offs += ALIGN(len, c->min_io_size);
c->ohead_offs = ALIGN(c->ohead_offs, 8);
return err;
}
/**
* write_orph_nodes - write orphan nodes until there are no more to commit.
* @c: UBIFS file-system description object
* @atomic: write atomically
*
* This function writes orphan nodes for all the orphans to commit. On success,
* %0 is returned, otherwise a negative error code is returned.
*/
static int write_orph_nodes(struct ubifs_info *c, int atomic)
{
int err;
while (c->cmt_orphans > 0) {
err = write_orph_node(c, atomic);
if (err)
return err;
}
if (atomic) {
int lnum;
/* Unmap any unused LEBs after consolidation */
for (lnum = c->ohead_lnum + 1; lnum <= c->orph_last; lnum++) {
err = ubifs_leb_unmap(c, lnum);
if (err)
return err;
}
}
return 0;
}
/**
* consolidate - consolidate the orphan area.
* @c: UBIFS file-system description object
*
* This function enables consolidation by putting all the orphans into the list
* to commit. The list is in the order that the orphans were added, and the
* LEBs are written atomically in order, so at no time can orphans be lost by
* an unclean unmount.
*
* This function returns %0 on success and a negative error code on failure.
*/
static int consolidate(struct ubifs_info *c)
{
int tot_avail = tot_avail_orphs(c), err = 0;
spin_lock(&c->orphan_lock);
dbg_cmt("there is space for %d orphans and there are %d",
tot_avail, c->tot_orphans);
if (c->tot_orphans - c->new_orphans <= tot_avail) {
struct ubifs_orphan *orphan, **last;
int cnt = 0;
/* Change the cnext list to include all non-new orphans */
last = &c->orph_cnext;
list_for_each_entry(orphan, &c->orph_list, list) {
if (orphan->new)
continue;
orphan->cmt = 1;
*last = orphan;
last = &orphan->cnext;
cnt += 1;
}
*last = NULL;
ubifs_assert(c, cnt == c->tot_orphans - c->new_orphans);
c->cmt_orphans = cnt;
c->ohead_lnum = c->orph_first;
c->ohead_offs = 0;
} else {
/*
* We limit the number of orphans so that this should
* never happen.
*/
ubifs_err(c, "out of space in orphan area");
err = -EINVAL;
}
spin_unlock(&c->orphan_lock);
return err;
}
/**
* commit_orphans - commit orphans.
* @c: UBIFS file-system description object
*
* This function commits orphans to flash. On success, %0 is returned,
* otherwise a negative error code is returned.
*/
static int commit_orphans(struct ubifs_info *c)
{
int avail, atomic = 0, err;
ubifs_assert(c, c->cmt_orphans > 0);
avail = avail_orphs(c);
if (avail < c->cmt_orphans) {
/* Not enough space to write new orphans, so consolidate */
err = consolidate(c);
if (err)
return err;
atomic = 1;
}
err = write_orph_nodes(c, atomic);
return err;
}
/**
* erase_deleted - erase the orphans marked for deletion.
* @c: UBIFS file-system description object
*
* During commit, the orphans being committed cannot be deleted, so they are
* marked for deletion and deleted by this function. Also, the recovery
* adds killed orphans to the deletion list, and therefore they are deleted
* here too.
*/
static void erase_deleted(struct ubifs_info *c)
{
struct ubifs_orphan *orphan, *dnext;
spin_lock(&c->orphan_lock);
dnext = c->orph_dnext;
while (dnext) {
orphan = dnext;
dnext = orphan->dnext;
ubifs_assert(c, !orphan->new);
ubifs_assert(c, orphan->del);
rb_erase(&orphan->rb, &c->orph_tree);
list_del(&orphan->list);
c->tot_orphans -= 1;
dbg_gen("deleting orphan ino %lu", (unsigned long)orphan->inum);
kfree(orphan);
}
c->orph_dnext = NULL;
spin_unlock(&c->orphan_lock);
}
/**
* ubifs_orphan_end_commit - end commit of orphans.
* @c: UBIFS file-system description object
*
* End commit of orphans.
*/
int ubifs_orphan_end_commit(struct ubifs_info *c)
{
int err;
if (c->cmt_orphans != 0) {
err = commit_orphans(c);
if (err)
return err;
}
erase_deleted(c);
err = dbg_check_orphans(c);
return err;
}
/**
* ubifs_clear_orphans - erase all LEBs used for orphans.
* @c: UBIFS file-system description object
*
* If recovery is not required, then the orphans from the previous session
* are not needed. This function locates the LEBs used to record
* orphans, and un-maps them.
*/
int ubifs_clear_orphans(struct ubifs_info *c)
{
int lnum, err;
for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
err = ubifs_leb_unmap(c, lnum);
if (err)
return err;
}
c->ohead_lnum = c->orph_first;
c->ohead_offs = 0;
return 0;
}
/**
* insert_dead_orphan - insert an orphan.
* @c: UBIFS file-system description object
* @inum: orphan inode number
*
* This function is a helper to the 'do_kill_orphans()' function. The orphan
* must be kept until the next commit, so it is added to the rb-tree and the
* deletion list.
*/
static int insert_dead_orphan(struct ubifs_info *c, ino_t inum)
{
struct ubifs_orphan *orphan, *o;
struct rb_node **p, *parent = NULL;
orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL);
if (!orphan)
return -ENOMEM;
orphan->inum = inum;
p = &c->orph_tree.rb_node;
while (*p) {
parent = *p;
o = rb_entry(parent, struct ubifs_orphan, rb);
if (inum < o->inum)
p = &(*p)->rb_left;
else if (inum > o->inum)
p = &(*p)->rb_right;
else {
/* Already added - no problem */
kfree(orphan);
return 0;
}
}
c->tot_orphans += 1;
rb_link_node(&orphan->rb, parent, p);
rb_insert_color(&orphan->rb, &c->orph_tree);
list_add_tail(&orphan->list, &c->orph_list);
orphan->del = 1;
orphan->dnext = c->orph_dnext;
c->orph_dnext = orphan;
dbg_mnt("ino %lu, new %d, tot %d", (unsigned long)inum,
c->new_orphans, c->tot_orphans);
return 0;
}
/**
* do_kill_orphans - remove orphan inodes from the index.
* @c: UBIFS file-system description object
* @sleb: scanned LEB
* @last_cmt_no: cmt_no of last orphan node read is passed and returned here
* @outofdate: whether the LEB is out of date is returned here
* @last_flagged: whether the end orphan node is encountered
*
* This function is a helper to the 'kill_orphans()' function. It goes through
* every orphan node in a LEB and for every inode number recorded, removes
* all keys for that inode from the TNC.
*/
static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
unsigned long long *last_cmt_no, int *outofdate,
int *last_flagged)
{
struct ubifs_scan_node *snod;
struct ubifs_orph_node *orph;
struct ubifs_ino_node *ino = NULL;
unsigned long long cmt_no;
ino_t inum;
int i, n, err, first = 1;
ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
if (!ino)
return -ENOMEM;
list_for_each_entry(snod, &sleb->nodes, list) {
if (snod->type != UBIFS_ORPH_NODE) {
ubifs_err(c, "invalid node type %d in orphan area at %d:%d",
snod->type, sleb->lnum, snod->offs);
ubifs_dump_node(c, snod->node,
c->leb_size - snod->offs);
err = -EINVAL;
goto out_free;
}
orph = snod->node;
/* Check commit number */
cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX;
/*
* The commit number on the master node may be less, because
* of a failed commit. If there are several failed commits in a
* row, the commit number written on orphan nodes will continue
* to increase (because the commit number is adjusted here) even
* though the commit number on the master node stays the same
* because the master node has not been re-written.
*/
if (cmt_no > c->cmt_no)
c->cmt_no = cmt_no;
if (cmt_no < *last_cmt_no && *last_flagged) {
/*
* The last orphan node had a higher commit number and
* was flagged as the last written for that commit
* number. That makes this orphan node, out of date.
*/
if (!first) {
ubifs_err(c, "out of order commit number %llu in orphan node at %d:%d",
cmt_no, sleb->lnum, snod->offs);
ubifs_dump_node(c, snod->node,
c->leb_size - snod->offs);
err = -EINVAL;
goto out_free;
}
dbg_rcvry("out of date LEB %d", sleb->lnum);
*outofdate = 1;
err = 0;
goto out_free;
}
if (first)
first = 0;
n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
for (i = 0; i < n; i++) {
union ubifs_key key1, key2;
inum = le64_to_cpu(orph->inos[i]);
ino_key_init(c, &key1, inum);
err = ubifs_tnc_lookup(c, &key1, ino);
if (err && err != -ENOENT)
goto out_free;
/*
* Check whether an inode can really get deleted.
* linkat() with O_TMPFILE allows rebirth of an inode.
*/
if (err == 0 && ino->nlink == 0) {
dbg_rcvry("deleting orphaned inode %lu",
(unsigned long)inum);
lowest_ino_key(c, &key1, inum);
highest_ino_key(c, &key2, inum);
err = ubifs_tnc_remove_range(c, &key1, &key2);
if (err)
goto out_ro;
}
err = insert_dead_orphan(c, inum);
if (err)
goto out_free;
}
*last_cmt_no = cmt_no;
if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) {
dbg_rcvry("last orph node for commit %llu at %d:%d",
cmt_no, sleb->lnum, snod->offs);
*last_flagged = 1;
} else
*last_flagged = 0;
}
err = 0;
out_free:
kfree(ino);
return err;
out_ro:
ubifs_ro_mode(c, err);
kfree(ino);
return err;
}
/**
* kill_orphans - remove all orphan inodes from the index.
* @c: UBIFS file-system description object
*
* If recovery is required, then orphan inodes recorded during the previous
* session (which ended with an unclean unmount) must be deleted from the index.
* This is done by updating the TNC, but since the index is not updated until
* the next commit, the LEBs where the orphan information is recorded are not
* erased until the next commit.
*/
static int kill_orphans(struct ubifs_info *c)
{
unsigned long long last_cmt_no = 0;
int lnum, err = 0, outofdate = 0, last_flagged = 0;
c->ohead_lnum = c->orph_first;
c->ohead_offs = 0;
/* Check no-orphans flag and skip this if no orphans */
if (c->no_orphs) {
dbg_rcvry("no orphans");
return 0;
}
/*
* Orph nodes always start at c->orph_first and are written to each
* successive LEB in turn. Generally unused LEBs will have been unmapped
* but may contain out of date orphan nodes if the unmap didn't go
* through. In addition, the last orphan node written for each commit is
* marked (top bit of orph->cmt_no is set to 1). It is possible that
* there are orphan nodes from the next commit (i.e. the commit did not
* complete successfully). In that case, no orphans will have been lost
* due to the way that orphans are written, and any orphans added will
* be valid orphans anyway and so can be deleted.
*/
for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
struct ubifs_scan_leb *sleb;
dbg_rcvry("LEB %d", lnum);
sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1);
if (IS_ERR(sleb)) {
if (PTR_ERR(sleb) == -EUCLEAN)
sleb = ubifs_recover_leb(c, lnum, 0,
c->sbuf, -1);
if (IS_ERR(sleb)) {
err = PTR_ERR(sleb);
break;
}
}
err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate,
&last_flagged);
if (err || outofdate) {
ubifs_scan_destroy(sleb);
break;
}
if (sleb->endpt) {
c->ohead_lnum = lnum;
c->ohead_offs = sleb->endpt;
}
ubifs_scan_destroy(sleb);
}
return err;
}
/**
* ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them.
* @c: UBIFS file-system description object
* @unclean: indicates recovery from unclean unmount
* @read_only: indicates read only mount
*
* This function is called when mounting to erase orphans from the previous
* session. If UBIFS was not unmounted cleanly, then the inodes recorded as
* orphans are deleted.
*/
int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only)
{
int err = 0;
c->max_orphans = tot_avail_orphs(c);
if (!read_only) {
c->orph_buf = vmalloc(c->leb_size);
if (!c->orph_buf)
return -ENOMEM;
}
if (unclean)
err = kill_orphans(c);
else if (!read_only)
err = ubifs_clear_orphans(c);
return err;
}
/*
* Everything below is related to debugging.
*/
struct check_orphan {
struct rb_node rb;
ino_t inum;
};
struct check_info {
unsigned long last_ino;
unsigned long tot_inos;
unsigned long missing;
unsigned long long leaf_cnt;
struct ubifs_ino_node *node;
struct rb_root root;
};
static bool dbg_find_orphan(struct ubifs_info *c, ino_t inum)
{
bool found = false;
spin_lock(&c->orphan_lock);
found = !!lookup_orphan(c, inum);
spin_unlock(&c->orphan_lock);
return found;
}
static int dbg_ins_check_orphan(struct rb_root *root, ino_t inum)
{
struct check_orphan *orphan, *o;
struct rb_node **p, *parent = NULL;
orphan = kzalloc(sizeof(struct check_orphan), GFP_NOFS);
if (!orphan)
return -ENOMEM;
orphan->inum = inum;
p = &root->rb_node;
while (*p) {
parent = *p;
o = rb_entry(parent, struct check_orphan, rb);
if (inum < o->inum)
p = &(*p)->rb_left;
else if (inum > o->inum)
p = &(*p)->rb_right;
else {
kfree(orphan);
return 0;
}
}
rb_link_node(&orphan->rb, parent, p);
rb_insert_color(&orphan->rb, root);
return 0;
}
static int dbg_find_check_orphan(struct rb_root *root, ino_t inum)
{
struct check_orphan *o;
struct rb_node *p;
p = root->rb_node;
while (p) {
o = rb_entry(p, struct check_orphan, rb);
if (inum < o->inum)
p = p->rb_left;
else if (inum > o->inum)
p = p->rb_right;
else
return 1;
}
return 0;
}
static void dbg_free_check_tree(struct rb_root *root)
{
struct check_orphan *o, *n;
rbtree_postorder_for_each_entry_safe(o, n, root, rb)
kfree(o);
}
static int dbg_orphan_check(struct ubifs_info *c, struct ubifs_zbranch *zbr,
void *priv)
{
struct check_info *ci = priv;
ino_t inum;
int err;
inum = key_inum(c, &zbr->key);
if (inum != ci->last_ino) {
/* Lowest node type is the inode node, so it comes first */
if (key_type(c, &zbr->key) != UBIFS_INO_KEY)
ubifs_err(c, "found orphan node ino %lu, type %d",
(unsigned long)inum, key_type(c, &zbr->key));
ci->last_ino = inum;
ci->tot_inos += 1;
err = ubifs_tnc_read_node(c, zbr, ci->node);
if (err) {
ubifs_err(c, "node read failed, error %d", err);
return err;
}
if (ci->node->nlink == 0)
/* Must be recorded as an orphan */
if (!dbg_find_check_orphan(&ci->root, inum) &&
!dbg_find_orphan(c, inum)) {
ubifs_err(c, "missing orphan, ino %lu",
(unsigned long)inum);
ci->missing += 1;
}
}
ci->leaf_cnt += 1;
return 0;
}
static int dbg_read_orphans(struct check_info *ci, struct ubifs_scan_leb *sleb)
{
struct ubifs_scan_node *snod;
struct ubifs_orph_node *orph;
ino_t inum;
int i, n, err;
list_for_each_entry(snod, &sleb->nodes, list) {
cond_resched();
if (snod->type != UBIFS_ORPH_NODE)
continue;
orph = snod->node;
n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
for (i = 0; i < n; i++) {
inum = le64_to_cpu(orph->inos[i]);
err = dbg_ins_check_orphan(&ci->root, inum);
if (err)
return err;
}
}
return 0;
}
static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci)
{
int lnum, err = 0;
void *buf;
/* Check no-orphans flag and skip this if no orphans */
if (c->no_orphs)
return 0;
buf = __vmalloc(c->leb_size, GFP_NOFS);
if (!buf) {
ubifs_err(c, "cannot allocate memory to check orphans");
return 0;
}
for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
struct ubifs_scan_leb *sleb;
sleb = ubifs_scan(c, lnum, 0, buf, 0);
if (IS_ERR(sleb)) {
err = PTR_ERR(sleb);
break;
}
err = dbg_read_orphans(ci, sleb);
ubifs_scan_destroy(sleb);
if (err)
break;
}
vfree(buf);
return err;
}
static int dbg_check_orphans(struct ubifs_info *c)
{
struct check_info ci;
int err;
if (!dbg_is_chk_orph(c))
return 0;
ci.last_ino = 0;
ci.tot_inos = 0;
ci.missing = 0;
ci.leaf_cnt = 0;
ci.root = RB_ROOT;
ci.node = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
if (!ci.node) {
ubifs_err(c, "out of memory");
return -ENOMEM;
}
err = dbg_scan_orphans(c, &ci);
if (err)
goto out;
err = dbg_walk_index(c, &dbg_orphan_check, NULL, &ci);
if (err) {
ubifs_err(c, "cannot scan TNC, error %d", err);
goto out;
}
if (ci.missing) {
ubifs_err(c, "%lu missing orphan(s)", ci.missing);
err = -EINVAL;
goto out;
}
dbg_cmt("last inode number is %lu", ci.last_ino);
dbg_cmt("total number of inodes is %lu", ci.tot_inos);
dbg_cmt("total number of leaf nodes is %llu", ci.leaf_cnt);
out:
dbg_free_check_tree(&ci.root);
kfree(ci.node);
return err;
}