create-function-to-read-journal-inode

   1 ext4: create function to read journal inode
   2
   3 From: Eric Whitney <enwlinux@gmail.com>
   4
   5 Factor out the code used in ext4_get_journal() to read a valid journal
   6 inode from storage, enabling its reuse in other functions.
   7
   8 Signed-off-by: Eric Whitney <enwlinux@gmail.com>
   9 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  10 ---
  11  fs/ext4/super.c | 32 +++++++++++++++++++++++---------
  12  1 file changed, 23 insertions(+), 9 deletions(-)
  13
  14 diff --git a/fs/ext4/super.c b/fs/ext4/super.c
  15 index 50912cc..4b0ca25 100644
  16 --- a/fs/ext4/super.c
  17 +++ b/fs/ext4/super.c
  18 @@ -78,6 +78,8 @@ static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  19  static void ext4_destroy_lazyinit_thread(void);
  20  static void ext4_unregister_li_request(struct super_block *sb);
  21  static void ext4_clear_request_list(void);
  22 +static struct inode *ext4_get_journal_inode(struct super_block *sb,
  23 +                                           unsigned int journal_inum);
  24
  25  /*
  26   * Lock ordering
  27 @@ -4237,18 +4239,16 @@ static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
  28         write_unlock(&journal->j_state_lock);
  29  }
  30
  31 -static journal_t *ext4_get_journal(struct super_block *sb,
  32 -                                  unsigned int journal_inum)
  33 +static struct inode *ext4_get_journal_inode(struct super_block *sb,
  34 +                                            unsigned int journal_inum)
  35  {
  36         struct inode *journal_inode;
  37 -       journal_t *journal;
  38 -
  39 -       BUG_ON(!ext4_has_feature_journal(sb));
  40 -
  41 -       /* First, test for the existence of a valid inode on disk.  Bad
  42 -        * things happen if we iget() an unused inode, as the subsequent
  43 -        * iput() will try to delete it. */
  44
  45 +       /*
  46 +        * Test for the existence of a valid inode on disk.  Bad things
  47 +        * happen if we iget() an unused inode, as the subsequent iput()
  48 +        * will try to delete it.
  49 +        */
  50         journal_inode = ext4_iget(sb, journal_inum);
  51         if (IS_ERR(journal_inode)) {
  52                 ext4_msg(sb, KERN_ERR, "no journal found");
  53 @@ -4268,6 +4268,20 @@ static journal_t *ext4_get_journal(struct super_block *sb,
  54                 iput(journal_inode);
  55                 return NULL;
  56         }
  57 +       return journal_inode;
  58 +}
  59 +
  60 +static journal_t *ext4_get_journal(struct super_block *sb,
  61 +                                  unsigned int journal_inum)
  62 +{
  63 +       struct inode *journal_inode;
  64 +       journal_t *journal;
  65 +
  66 +       BUG_ON(!ext4_has_feature_journal(sb));
  67 +
  68 +       journal_inode = ext4_get_journal_inode(sb, journal_inum);
  69 +       if (!journal_inode)
  70 +               return NULL;
  71
  72         journal = jbd2_journal_init_inode(journal_inode);
  73         if (!journal) {
  74 --
  75 2.1.4
  76
  77