ext4: cleanup ext4_get_dev_journal() and ext4_get_journal()

Factor out a new helper form ext4_get_dev_journal() to get external
journal bdev and check validation of this device, drop ext4_blkdev_get()
helper, and also remove duplicate check of journal feature. It makes
ext4_get_dev_journal() more clear than before.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230811063610.2980059-12-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Zhang Yi 2023-08-11 14:36:09 +08:00 committed by Theodore Ts'o
parent 8e6cf5fbb7
commit bc74e6a38d

View file

@ -1105,26 +1105,6 @@ static const struct blk_holder_ops ext4_holder_ops = {
.mark_dead = ext4_bdev_mark_dead,
};
/*
* Open the external journal device
*/
static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
{
struct block_device *bdev;
bdev = blkdev_get_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE, sb,
&ext4_holder_ops);
if (IS_ERR(bdev))
goto fail;
return bdev;
fail:
ext4_msg(sb, KERN_ERR,
"failed to open journal device unknown-block(%u,%u) %ld",
MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
return NULL;
}
/*
* Release the journal device
*/
@ -5768,14 +5748,14 @@ static struct inode *ext4_get_journal_inode(struct super_block *sb,
ext4_msg(sb, KERN_ERR, "journal inode is deleted");
return NULL;
}
ext4_debug("Journal inode found at %p: %lld bytes\n",
journal_inode, journal_inode->i_size);
if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
ext4_msg(sb, KERN_ERR, "invalid journal inode");
iput(journal_inode);
return NULL;
}
ext4_debug("Journal inode found at %p: %lld bytes\n",
journal_inode, journal_inode->i_size);
return journal_inode;
}
@ -5807,9 +5787,6 @@ static journal_t *ext4_get_journal(struct super_block *sb,
struct inode *journal_inode;
journal_t *journal;
if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
return NULL;
journal_inode = ext4_get_journal_inode(sb, journal_inum);
if (!journal_inode)
return NULL;
@ -5826,25 +5803,25 @@ static journal_t *ext4_get_journal(struct super_block *sb,
return journal;
}
static journal_t *ext4_get_dev_journal(struct super_block *sb,
dev_t j_dev)
static struct block_device *ext4_get_journal_blkdev(struct super_block *sb,
dev_t j_dev, ext4_fsblk_t *j_start,
ext4_fsblk_t *j_len)
{
struct buffer_head *bh;
journal_t *journal;
ext4_fsblk_t start;
ext4_fsblk_t len;
struct block_device *bdev;
int hblock, blocksize;
ext4_fsblk_t sb_block;
unsigned long offset;
struct ext4_super_block *es;
struct block_device *bdev;
if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
return NULL;
bdev = ext4_blkdev_get(j_dev, sb);
if (bdev == NULL)
bdev = blkdev_get_by_dev(j_dev, BLK_OPEN_READ | BLK_OPEN_WRITE, sb,
&ext4_holder_ops);
if (IS_ERR(bdev)) {
ext4_msg(sb, KERN_ERR,
"failed to open journal device unknown-block(%u,%u) %ld",
MAJOR(j_dev), MINOR(j_dev), PTR_ERR(bdev));
return NULL;
}
blocksize = sb->s_blocksize;
hblock = bdev_logical_block_size(bdev);
@ -5857,7 +5834,8 @@ static journal_t *ext4_get_dev_journal(struct super_block *sb,
sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
offset = EXT4_MIN_BLOCK_SIZE % blocksize;
set_blocksize(bdev, blocksize);
if (!(bh = __bread(bdev, sb_block, blocksize))) {
bh = __bread(bdev, sb_block, blocksize);
if (!bh) {
ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
"external journal");
goto out_bdev;
@ -5867,56 +5845,67 @@ static journal_t *ext4_get_dev_journal(struct super_block *sb,
if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
!(le32_to_cpu(es->s_feature_incompat) &
EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
ext4_msg(sb, KERN_ERR, "external journal has "
"bad superblock");
brelse(bh);
goto out_bdev;
ext4_msg(sb, KERN_ERR, "external journal has bad superblock");
goto out_bh;
}
if ((le32_to_cpu(es->s_feature_ro_compat) &
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
es->s_checksum != ext4_superblock_csum(sb, es)) {
ext4_msg(sb, KERN_ERR, "external journal has "
"corrupt superblock");
brelse(bh);
goto out_bdev;
ext4_msg(sb, KERN_ERR, "external journal has corrupt superblock");
goto out_bh;
}
if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
ext4_msg(sb, KERN_ERR, "journal UUID does not match");
brelse(bh);
goto out_bdev;
goto out_bh;
}
len = ext4_blocks_count(es);
start = sb_block + 1;
brelse(bh); /* we're done with the superblock */
*j_start = sb_block + 1;
*j_len = ext4_blocks_count(es);
brelse(bh);
return bdev;
journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
start, len, blocksize);
out_bh:
brelse(bh);
out_bdev:
blkdev_put(bdev, sb);
return NULL;
}
static journal_t *ext4_get_dev_journal(struct super_block *sb,
dev_t j_dev)
{
journal_t *journal;
ext4_fsblk_t j_start;
ext4_fsblk_t j_len;
struct block_device *journal_bdev;
journal_bdev = ext4_get_journal_blkdev(sb, j_dev, &j_start, &j_len);
if (!journal_bdev)
return NULL;
journal = jbd2_journal_init_dev(journal_bdev, sb->s_bdev, j_start,
j_len, sb->s_blocksize);
if (IS_ERR(journal)) {
ext4_msg(sb, KERN_ERR, "failed to create device journal");
goto out_bdev;
}
journal->j_private = sb;
if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
ext4_msg(sb, KERN_ERR, "I/O error on journal device");
goto out_journal;
}
if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
ext4_msg(sb, KERN_ERR, "External journal has more than one "
"user (unsupported) - %d",
be32_to_cpu(journal->j_superblock->s_nr_users));
goto out_journal;
}
EXT4_SB(sb)->s_journal_bdev = bdev;
journal->j_private = sb;
EXT4_SB(sb)->s_journal_bdev = journal_bdev;
ext4_init_journal_params(sb, journal);
return journal;
out_journal:
jbd2_journal_destroy(journal);
out_bdev:
blkdev_put(bdev, sb);
blkdev_put(journal_bdev, sb);
return NULL;
}