From: Zhang Yi <yi.zhang@xxxxxxxxxx> 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@xxxxxxxxxx> --- fs/ext4/super.c | 109 ++++++++++++++++++++++-------------------------- 1 file changed, 49 insertions(+), 60 deletions(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index ce2e02b139af..2f71076f678a 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -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 */ @@ -5780,14 +5760,14 @@ 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; } @@ -5819,9 +5799,6 @@ 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; @@ -5838,25 +5815,25 @@ 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_dev(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); @@ -5869,7 +5846,8 @@ 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; @@ -5879,56 +5857,67 @@ 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; + +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_dev(sb, j_dev, &j_start, &j_len); + if (!journal_bdev) + return NULL; - journal = jbd2_journal_init_dev(bdev, sb->s_bdev, - start, len, blocksize); + 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; } -- 2.34.3