/*
* Ext4 orphan inode handling
*/
#include <linux/fs.h>
#include <linux/quotaops.h>
#include <linux/buffer_head.h>
#include "ext4.h"
#include "ext4_jbd2.h"
static int ext4_orphan_file_add(handle_t *handle, struct inode *inode)
{
int i, j, start;
struct ext4_orphan_info *oi = &EXT4_SB(inode->i_sb)->s_orphan_info;
int ret = 0;
bool found = false;
__le32 *bdata;
int inodes_per_ob = ext4_inodes_per_orphan_block(inode->i_sb);
int looped = 0;
/*
* Find block with free orphan entry. Use CPU number for a naive hash
* for a search start in the orphan file
*/
start = raw_smp_processor_id()*13 % oi->of_blocks;
i = start;
do {
if (atomic_dec_if_positive(&oi->of_binfo[i].ob_free_entries)
>= 0) {
found = true;
break;
}
if (++i >= oi->of_blocks)
i = 0;
} while (i != start);
if (!found) {
/*
* For now we don't grow or shrink orphan file. We just use
* whatever was allocated at mke2fs time. The additional
* credits we would have to reserve for each orphan inode
* operation just don't seem worth it.
*/
return -ENOSPC;
}
ret = ext4_journal_get_write_access(handle, inode->i_sb,
oi->of_binfo[i].ob_bh, EXT4_JTR_ORPHAN_FILE);
if (ret) {
atomic_inc(&oi->of_binfo[i].ob_free_entries);
return ret;
}
bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
/* Find empty slot in a block */
j = 0;
do {
if (looped) {
/*
* Did we walk through the block several times without
* finding free entry? It is theoretically possible
* if entries get constantly allocated and freed or
* if the block is corrupted. Avoid indefinite looping
* and bail. We'll use orphan list instead.
*/
if (looped > 3) {
atomic_inc(&oi->of_binfo[i].ob_free_entries);
return -ENOSPC;
}
cond_resched();
}
while (bdata[j]) {
if (++j >= inodes_per_ob) {
j = 0;
looped++;
}
}
} while (cmpxchg(&bdata[j], (__le32)0, cpu_to_le32(inode->i_ino)) !=
(__le32)0);
EXT4_I(inode)->i_orphan_idx = i * inodes_per_ob + j;
ext4_set_inode_state(inode, EXT4_STATE_ORPHAN_FILE);
return ext4_handle_dirty_metadata(handle, NULL, oi->of_binfo[i].ob_bh);
}
/*
* ext4_orphan_add() links an unlinked or truncated inode into a list of
* such inodes, starting at the superblock, in case we crash before the
* file is closed/deleted, or in case the inode truncate spans multiple
* transactions and the last transaction is not recovered after a crash.
*
* At filesystem recovery time, we walk this list deleting unlinked
* inodes and truncating linked inodes in ext4_orphan_cleanup().
*
* Orphan list manipulation functions must be called under i_rwsem unless
* we are just creating the inode or deleting it.
*/
int ext4_orphan_add(handle_t *handle, struct inode *inode)
{
struct super_block *sb = inode->i_sb;
struct ext4_sb_info *sbi = EXT4_SB(sb);
struct ext4_iloc iloc;
int err = 0, rc;
bool dirty = false;
if (!sbi->s_journal || is_bad_inode(inode))
return 0;
WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
!inode_is_locked(inode));
/*
* Inode orphaned in orphan file or in orphan list?
*/
if (ext4_test_inode_state(inode, EXT4_STATE_ORPHAN_FILE) ||
!list_empty(&EXT4_I(inode)->i_orphan))
return 0;
/*
* Orphan handling is only valid for files with data blocks
* being truncated, or files being unlinked. Note that we either
* hold i_rwsem, or the inode can not be referenced from outside,
* so i_nlink should not be bumped due to race
*/
ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
if (sbi->s_orphan_info.of_blocks) {
err = ext4_orphan_file_add(handle, inode);
/*
* Fallback to normal orphan list of orphan file is
* out of space
*/
if (err != -ENOSPC)
return err;
}
BUFFER_TRACE(sbi->s_sbh, "get_write_access");
err = ext4_journal_get_write_access(handle, sb, sbi->s_sbh,
EXT4_JTR_NONE);
if (err)
goto out;
err = ext4_reserve_inode_write(handle, inode, &iloc);
if (err)
goto out;
mutex_lock(&sbi->s_orphan_lock);
/*
* Due to previous errors inode may be already a part of on-disk
* orphan list. If so skip on-disk list modification.
*/
if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) >
(le32_to_cpu(sbi->s_es->s_inodes_count))) {
/* Insert this inode at the head of the on-disk orphan list */
NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
lock_buffer(sbi->s_sbh);
sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
ext4_superblock_csum_set(sb);
unlock_buffer(sbi->s_sbh);
dirty = true;
}
list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
mutex_unlock(&sbi->s_orphan_lock);
if (dirty) {
err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
if (!err)
err = rc;
if (err) {
/*
* We have to remove inode from in-memory list if
* addition to on disk orphan list failed. Stray orphan
* list entries can cause panics at unmount time.
*/
mutex_lock(&sbi->s_orphan_lock);
list_del_init(&EXT4_I(inode)->i_orphan);
mutex_unlock(&sbi->s_orphan_lock);
}
} else
brelse(iloc.bh);
ext4_debug("superblock will point to %lu\n", inode->i_ino);
ext4_debug("orphan inode %lu will point to %d\n",
inode->i_ino, NEXT_ORPHAN(inode));
out:
ext4_std_error(sb, err);
return err;
}
static int ext4_orphan_file_del(handle_t *handle, struct inode *inode)
{
struct ext4_orphan_info *oi = &EXT4_SB(inode->i_sb)->s_orphan_info;
__le32 *bdata;
int blk, off;
int inodes_per_ob = ext4_inodes_per_orphan_block(inode->i_sb);
int ret = 0;
if (!handle)
goto out;
blk = EXT4_I(inode)->i_orphan_idx / inodes_per_ob;
off = EXT4_I(inode)->i_orphan_idx % inodes_per_ob;
if (WARN_ON_ONCE(blk >= oi->of_blocks))
goto out;
ret = ext4_journal_get_write_access(handle, inode->i_sb,
oi->of_binfo[blk].ob_bh, EXT4_JTR_ORPHAN_FILE);
if (ret)
goto out;
bdata = (__le32 *)(oi->of_binfo[blk].ob_bh->b_data);
bdata[off] = 0;
atomic_inc(&oi->of_binfo[blk].ob_free_entries);
ret = ext4_handle_dirty_metadata(handle, NULL, oi->of_binfo[blk].ob_bh);
out:
ext4_clear_inode_state(inode, EXT4_STATE_ORPHAN_FILE);
INIT_LIST_HEAD(&EXT4_I(inode)->i_orphan);
return ret;
}
/*
* ext4_orphan_del() removes an unlinked or truncated inode from the list
* of such inodes stored on disk, because it is finally being cleaned up.
*/
int ext4_orphan_del(handle_t *handle, struct inode *inode)
{
struct list_head *prev;
struct ext4_inode_info *ei = EXT4_I(inode);
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
__u32 ino_next;
struct ext4_iloc iloc;
int err = 0;
if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
return 0;
WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
!inode_is_locked(inode));
if (ext4_test_inode_state(inode, EXT4_STATE_ORPHAN_FILE))
return ext4_orphan_file_del(handle, inode);
/* Do this quick check before taking global s_orphan_lock. */
if (list_empty(&ei->i_orphan))
return 0;
if (handle) {
/* Grab inode buffer early before taking global s_orphan_lock */
err = ext4_reserve_inode_write(handle, inode, &iloc);
}
mutex_lock(&sbi->s_orphan_lock);
ext4_debug("remove inode %lu from orphan list\n", inode->i_ino);
prev = ei->i_orphan.prev;
list_del_init(&ei->i_orphan);
/* If we're on an error path, we may not have a valid
* transaction handle with which to update the orphan list on
* disk, but we still need to remove the inode from the linked
* list in memory. */
if (!handle || err) {
mutex_unlock(&sbi->s_orphan_lock);
goto out_err;
}
ino_next = NEXT_ORPHAN(inode);
if (prev == &sbi->s_orphan) {
ext4_debug("superblock will point to %u\n", ino_next);
BUFFER_TRACE(sbi->s_sbh, "get_write_access");
err = ext4_journal_get_write_access(handle, inode->i_sb,
sbi->s_sbh, EXT4_JTR_NONE);
if (err) {
mutex_unlock(&sbi->s_orphan_lock);
goto out_brelse;
}
lock_buffer(sbi->s_sbh);
sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
ext4_superblock_csum_set(inode->i_sb);
unlock_buffer(sbi->s_sbh);
mutex_unlock(&sbi->s_orphan_lock);
err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
} else {
struct ext4_iloc iloc2;
struct inode *i_prev =
&list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
ext4_debug("orphan inode %lu will point to %u\n",
i_prev->i_ino, ino_next);
err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
if (err) {
mutex_unlock(&sbi->s_orphan_lock);
goto out_brelse;
}
NEXT_ORPHAN(i_prev) = ino_next;
err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
mutex_unlock(&sbi->s_orphan_lock);
}
if (err)
goto out_brelse;
NEXT_ORPHAN(inode) = 0;
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
out_err:
ext4_std_error(inode->i_sb, err);
return err;
out_brelse:
brelse(iloc.bh);
goto out_err;
}
#ifdef CONFIG_QUOTA
static int ext4_quota_on_mount(struct super_block *sb, int type)
{
return dquot_quota_on_mount(sb,
rcu_dereference_protected(EXT4_SB(sb)->s_qf_names[type],
lockdep_is_held(&sb->s_umount)),
EXT4_SB(sb)->s_jquota_fmt, type);
}
#endif
static void ext4_process_orphan(struct inode *inode,
int *nr_truncates, int *nr_orphans)
{
struct super_block *sb = inode->i_sb;
int ret;
dquot_initialize(inode);
if (inode->i_nlink) {
if (test_opt(sb, DEBUG))
ext4_msg(sb, KERN_DEBUG,
"%s: truncating inode %lu to %lld bytes",
__func__, inode->i_ino, inode->i_size);
ext4_debug("truncating inode %lu to %lld bytes\n",
inode->i_ino, inode->i_size);
inode_lock(inode);
truncate_inode_pages(inode->i_mapping, inode->i_size);
ret = ext4_truncate(inode);
if (ret) {
/*
* We need to clean up the in-core orphan list
* manually if ext4_truncate() failed to get a
* transaction handle.
*/
ext4_orphan_del(NULL, inode);
ext4_std_error(inode->i_sb, ret);
}
inode_unlock(inode);
(*nr_truncates)++;
} else {
if (test_opt(sb, DEBUG))
ext4_msg(sb, KERN_DEBUG,
"%s: deleting unreferenced inode %lu",
__func__, inode->i_ino);
ext4_debug("deleting unreferenced inode %lu\n",
inode->i_ino);
(*nr_orphans)++;
}
iput(inode); /* The delete magic happens here! */
}
/* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
* the superblock) which were deleted from all directories, but held open by
* a process at the time of a crash. We walk the list and try to delete these
* inodes at recovery time (only with a read-write filesystem).
*
* In order to keep the orphan inode chain consistent during traversal (in
* case of crash during recovery), we link each inode into the superblock
* orphan list_head and handle it the same way as an inode deletion during
* normal operation (which journals the operations for us).
*
* We only do an iget() and an iput() on each inode, which is very safe if we
* accidentally point at an in-use or already deleted inode. The worst that
* can happen in this case is that we get a "bit already cleared" message from
* ext4_free_inode(). The only reason we would point at a wrong inode is if
* e2fsck was run on this filesystem, and it must have already done the orphan
* inode cleanup for us, so we can safely abort without any further action.
*/
void ext4_orphan_cleanup(struct super_block *sb, struct ext4_super_block *es)
{
unsigned int s_flags = sb->s_flags;
int nr_orphans = 0, nr_truncates = 0;
struct inode *inode;
int i, j;
#ifdef CONFIG_QUOTA
int quota_update = 0;
#endif
__le32 *bdata;
struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
if (!es->s_last_orphan && !oi->of_blocks) {
ext4_debug("no orphan inodes to clean up\n");
return;
}
if (bdev_read_only(sb->s_bdev)) {
ext4_msg(sb, KERN_ERR, "write access "
"unavailable, skipping orphan cleanup");
return;
}
/* Check if feature set would not allow a r/w mount */
if (!ext4_feature_set_ok(sb, 0)) {
ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
"unknown ROCOMPAT features");
return;
}
if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
/* don't clear list on RO mount w/ errors */
if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
"clearing orphan list.");
es->s_last_orphan = 0;
}
ext4_debug("Skipping orphan recovery on fs with errors.\n");
return;
}
if (s_flags & SB_RDONLY) {
ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
sb->s_flags &= ~SB_RDONLY;
}
#ifdef CONFIG_QUOTA
/*
* Turn on quotas which were not enabled for read-only mounts if
* filesystem has quota feature, so that they are updated correctly.
*/
if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
int ret = ext4_enable_quotas(sb);
if (!ret)
quota_update = 1;
else
ext4_msg(sb, KERN_ERR,
"Cannot turn on quotas: error %d", ret);
}
/* Turn on journaled quotas used for old sytle */
for (i = 0; i < EXT4_MAXQUOTAS; i++) {
if (EXT4_SB(sb)->s_qf_names[i]) {
int ret = ext4_quota_on_mount(sb, i);
if (!ret)
quota_update = 1;
else
ext4_msg(sb, KERN_ERR,
"Cannot turn on journaled "
"quota: type %d: error %d", i, ret);
}
}
#endif
while (es->s_last_orphan) {
/*
* We may have encountered an error during cleanup; if
* so, skip the rest.
*/
if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
ext4_debug("Skipping orphan recovery on fs with errors.\n");
es->s_last_orphan = 0;
break;
}
inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
if (IS_ERR(inode)) {
es->s_last_orphan = 0;
break;
}
list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
ext4_process_orphan(inode, &nr_truncates, &nr_orphans);
}
for (i = 0; i < oi->of_blocks; i++) {
bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
for (j = 0; j < inodes_per_ob; j++) {
if (!bdata[j])
continue;
inode = ext4_orphan_get(sb, le32_to_cpu(bdata[j]));
if (IS_ERR(inode))
continue;
ext4_set_inode_state(inode, EXT4_STATE_ORPHAN_FILE);
EXT4_I(inode)->i_orphan_idx = i * inodes_per_ob + j;
ext4_process_orphan(inode, &nr_truncates, &nr_orphans);
}
}
#define PLURAL(x) (x), ((x) == 1) ? "" : "s"
if (nr_orphans)
ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
PLURAL(nr_orphans));
if (nr_truncates)
ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
PLURAL(nr_truncates));
#ifdef CONFIG_QUOTA
/* Turn off quotas if they were enabled for orphan cleanup */
if (quota_update) {
for (i = 0; i < EXT4_MAXQUOTAS; i++) {
if (sb_dqopt(sb)->files[i])
dquot_quota_off(sb, i);
}
}
#endif
sb->s_flags = s_flags; /* Restore SB_RDONLY status */
}
void ext4_release_orphan_info(struct super_block *sb)
{
int i;
struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
if (!oi->of_blocks)
return;
for (i = 0; i < oi->of_blocks; i++)
brelse(oi->of_binfo[i].ob_bh);
kfree(oi->of_binfo);
}
static struct ext4_orphan_block_tail *ext4_orphan_block_tail(
struct super_block *sb,
struct buffer_head *bh)
{
return (struct ext4_orphan_block_tail *)(bh->b_data + sb->s_blocksize -
sizeof(struct ext4_orphan_block_tail));
}
static int ext4_orphan_file_block_csum_verify(struct super_block *sb,
struct buffer_head *bh)
{
__u32 calculated;
int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
struct ext4_orphan_block_tail *ot;
__le64 dsk_block_nr = cpu_to_le64(bh->b_blocknr);
if (!ext4_has_metadata_csum(sb))
return 1;
ot = ext4_orphan_block_tail(sb, bh);
calculated = ext4_chksum(EXT4_SB(sb), oi->of_csum_seed,
(__u8 *)&dsk_block_nr, sizeof(dsk_block_nr));
calculated = ext4_chksum(EXT4_SB(sb), calculated, (__u8 *)bh->b_data,
inodes_per_ob * sizeof(__u32));
return le32_to_cpu(ot->ob_checksum) == calculated;
}
/* This gets called only when checksumming is enabled */
void ext4_orphan_file_block_trigger(struct jbd2_buffer_trigger_type *triggers,
struct buffer_head *bh,
void *data, size_t size)
{
struct super_block *sb = EXT4_TRIGGER(triggers)->sb;
__u32 csum;
int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
struct ext4_orphan_block_tail *ot;
__le64 dsk_block_nr = cpu_to_le64(bh->b_blocknr);
csum = ext4_chksum(EXT4_SB(sb), oi->of_csum_seed,
(__u8 *)&dsk_block_nr, sizeof(dsk_block_nr));
csum = ext4_chksum(EXT4_SB(sb), csum, (__u8 *)data,
inodes_per_ob * sizeof(__u32));
ot = ext4_orphan_block_tail(sb, bh);
ot->ob_checksum = cpu_to_le32(csum);
}
int ext4_init_orphan_info(struct super_block *sb)
{
struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
struct inode *inode;
int i, j;
int ret;
int free;
__le32 *bdata;
int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
struct ext4_orphan_block_tail *ot;
ino_t orphan_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_orphan_file_inum);
if (!ext4_has_feature_orphan_file(sb))
return 0;
inode = ext4_iget(sb, orphan_ino, EXT4_IGET_SPECIAL);
if (IS_ERR(inode)) {
ext4_msg(sb, KERN_ERR, "get orphan inode failed");
return PTR_ERR(inode);
}
oi->of_blocks = inode->i_size >> sb->s_blocksize_bits;
oi->of_csum_seed = EXT4_I(inode)->i_csum_seed;
oi->of_binfo = kmalloc(oi->of_blocks*sizeof(struct ext4_orphan_block),
GFP_KERNEL);
if (!oi->of_binfo) {
ret = -ENOMEM;
goto out_put;
}
for (i = 0; i < oi->of_blocks; i++) {
oi->of_binfo[i].ob_bh = ext4_bread(NULL, inode, i, 0);
if (IS_ERR(oi->of_binfo[i].ob_bh)) {
ret = PTR_ERR(oi->of_binfo[i].ob_bh);
goto out_free;
}
if (!oi->of_binfo[i].ob_bh) {
ret = -EIO;
goto out_free;
}
ot = ext4_orphan_block_tail(sb, oi->of_binfo[i].ob_bh);
if (le32_to_cpu(ot->ob_magic) != EXT4_ORPHAN_BLOCK_MAGIC) {
ext4_error(sb, "orphan file block %d: bad magic", i);
ret = -EIO;
goto out_free;
}
if (!ext4_orphan_file_block_csum_verify(sb,
oi->of_binfo[i].ob_bh)) {
ext4_error(sb, "orphan file block %d: bad checksum", i);
ret = -EIO;
goto out_free;
}
bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
free = 0;
for (j = 0; j < inodes_per_ob; j++)
if (bdata[j] == 0)
free++;
atomic_set(&oi->of_binfo[i].ob_free_entries, free);
}
iput(inode);
return 0;
out_free:
for (i--; i >= 0; i--)
brelse(oi->of_binfo[i].ob_bh);
kfree(oi->of_binfo);
out_put:
iput(inode);
return ret;
}
int ext4_orphan_file_empty(struct super_block *sb)
{
struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
int i;
int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
if (!ext4_has_feature_orphan_file(sb))
return 1;
for (i = 0; i < oi->of_blocks; i++)
if (atomic_read(&oi->of_binfo[i].ob_free_entries) !=
inodes_per_ob)
return 0;
return 1;
}
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