add patch create-function-to-read-journal-inode

[ext4-patch-queue.git] / move-more-common-code-into-journal_init_common

jbd2: move more common code into journal_init_common()

From: Geliang Tang <geliangtang@gmail.com>

There are some repetitive code in jbd2_journal_init_dev() and
jbd2_journal_init_inode(). So this patch moves the common code into
journal_init_common() helper to simplify the code. And fix the coding
style warnings reported by checkpatch.pl by the way.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 fs/jbd2/journal.c | 131 +++++++++++++++++++++++++++++++++-----------------------------------------------------
 1 file changed, 50 insertions(+), 81 deletions(-)

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 46261a6..927da49 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1090,11 +1090,15 @@ static void jbd2_stats_proc_exit(journal_t *journal)
  * very few fields yet: that has to wait until we have created the
  * journal structures from from scratch, or loaded them from disk. */
 
-static journal_t * journal_init_common (void)
+static journal_t *journal_init_common(struct block_device *bdev,
+                       struct block_device *fs_dev,
+                       unsigned long long start, int len, int blocksize)
 {
        static struct lock_class_key jbd2_trans_commit_key;
        journal_t *journal;
        int err;
+       struct buffer_head *bh;
+       int n;
 
        journal = kzalloc(sizeof(*journal), GFP_KERNEL);
        if (!journal)
@@ -1131,6 +1135,32 @@ static journal_t * journal_init_common (void)
        lockdep_init_map(&journal->j_trans_commit_map, "jbd2_handle",
                         &jbd2_trans_commit_key, 0);
 
+       /* journal descriptor can store up to n blocks -bzzz */
+       journal->j_blocksize = blocksize;
+       journal->j_dev = bdev;
+       journal->j_fs_dev = fs_dev;
+       journal->j_blk_offset = start;
+       journal->j_maxlen = len;
+       n = journal->j_blocksize / sizeof(journal_block_tag_t);
+       journal->j_wbufsize = n;
+       journal->j_wbuf = kmalloc_array(n, sizeof(struct buffer_head *),
+                                       GFP_KERNEL);
+       if (!journal->j_wbuf) {
+               kfree(journal);
+               return NULL;
+       }
+
+       bh = getblk_unmovable(journal->j_dev, start, journal->j_blocksize);
+       if (!bh) {
+               pr_err("%s: Cannot get buffer for journal superblock\n",
+                       __func__);
+               kfree(journal->j_wbuf);
+               kfree(journal);
+               return NULL;
+       }
+       journal->j_sb_buffer = bh;
+       journal->j_superblock = (journal_superblock_t *)bh->b_data;
+
        return journal;
 }
 
@@ -1157,51 +1187,21 @@ static journal_t * journal_init_common (void)
  *  range of blocks on an arbitrary block device.
  *
  */
-journal_t * jbd2_journal_init_dev(struct block_device *bdev,
+journal_t *jbd2_journal_init_dev(struct block_device *bdev,
                        struct block_device *fs_dev,
                        unsigned long long start, int len, int blocksize)
 {
-       journal_t *journal = journal_init_common();
-       struct buffer_head *bh;
-       int n;
+       journal_t *journal;
 
+       journal = journal_init_common(bdev, fs_dev, start, len, blocksize);
        if (!journal)
                return NULL;
 
-       /* journal descriptor can store up to n blocks -bzzz */
-       journal->j_blocksize = blocksize;
-       journal->j_dev = bdev;
-       journal->j_fs_dev = fs_dev;
-       journal->j_blk_offset = start;
-       journal->j_maxlen = len;
        bdevname(journal->j_dev, journal->j_devname);
        strreplace(journal->j_devname, '/', '!');
        jbd2_stats_proc_init(journal);
-       n = journal->j_blocksize / sizeof(journal_block_tag_t);
-       journal->j_wbufsize = n;
-       journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL);
-       if (!journal->j_wbuf) {
-               printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n",
-                       __func__);
-               goto out_err;
-       }
-
-       bh = __getblk(journal->j_dev, start, journal->j_blocksize);
-       if (!bh) {
-               printk(KERN_ERR
-                      "%s: Cannot get buffer for journal superblock\n",
-                      __func__);
-               goto out_err;
-       }
-       journal->j_sb_buffer = bh;
-       journal->j_superblock = (journal_superblock_t *)bh->b_data;
 
        return journal;
-out_err:
-       kfree(journal->j_wbuf);
-       jbd2_stats_proc_exit(journal);
-       kfree(journal);
-       return NULL;
 }
 
 /**
@@ -1212,67 +1212,36 @@ out_err:
  * the journal.  The inode must exist already, must support bmap() and
  * must have all data blocks preallocated.
  */
-journal_t * jbd2_journal_init_inode (struct inode *inode)
+journal_t *jbd2_journal_init_inode(struct inode *inode)
 {
-       struct buffer_head *bh;
-       journal_t *journal = journal_init_common();
+       journal_t *journal;
        char *p;
-       int err;
-       int n;
        unsigned long long blocknr;
 
+       blocknr = bmap(inode, 0);
+       if (!blocknr) {
+               pr_err("%s: Cannot locate journal superblock\n",
+                       __func__);
+               return NULL;
+       }
+
+       jbd_debug(1, "JBD2: inode %s/%ld, size %lld, bits %d, blksize %ld\n",
+                 inode->i_sb->s_id, inode->i_ino, (long long) inode->i_size,
+                 inode->i_sb->s_blocksize_bits, inode->i_sb->s_blocksize);
+
+       journal = journal_init_common(inode->i_sb->s_bdev, inode->i_sb->s_bdev,
+                       blocknr, inode->i_size >> inode->i_sb->s_blocksize_bits,
+                       inode->i_sb->s_blocksize);
        if (!journal)
                return NULL;
 
-       journal->j_dev = journal->j_fs_dev = inode->i_sb->s_bdev;
        journal->j_inode = inode;
        bdevname(journal->j_dev, journal->j_devname);
        p = strreplace(journal->j_devname, '/', '!');
        sprintf(p, "-%lu", journal->j_inode->i_ino);
-       jbd_debug(1,
-                 "journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n",
-                 journal, inode->i_sb->s_id, inode->i_ino,
-                 (long long) inode->i_size,
-                 inode->i_sb->s_blocksize_bits, inode->i_sb->s_blocksize);
-
-       journal->j_maxlen = inode->i_size >> inode->i_sb->s_blocksize_bits;
-       journal->j_blocksize = inode->i_sb->s_blocksize;
        jbd2_stats_proc_init(journal);
 
-       /* journal descriptor can store up to n blocks -bzzz */
-       n = journal->j_blocksize / sizeof(journal_block_tag_t);
-       journal->j_wbufsize = n;
-       journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL);
-       if (!journal->j_wbuf) {
-               printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n",
-                       __func__);
-               goto out_err;
-       }
-
-       err = jbd2_journal_bmap(journal, 0, &blocknr);
-       /* If that failed, give up */
-       if (err) {
-               printk(KERN_ERR "%s: Cannot locate journal superblock\n",
-                      __func__);
-               goto out_err;
-       }
-
-       bh = getblk_unmovable(journal->j_dev, blocknr, journal->j_blocksize);
-       if (!bh) {
-               printk(KERN_ERR
-                      "%s: Cannot get buffer for journal superblock\n",
-                      __func__);
-               goto out_err;
-       }
-       journal->j_sb_buffer = bh;
-       journal->j_superblock = (journal_superblock_t *)bh->b_data;
-
        return journal;
-out_err:
-       kfree(journal->j_wbuf);
-       jbd2_stats_proc_exit(journal);
-       kfree(journal);
-       return NULL;
 }
 
 /*