jbd2: factor out journal initialization from journal_get_superblock()

Current journal_get_superblock() couple journal superblock checking and
partial journal initialization, factor out initialization part from it
to make things clear.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230315013128.3911115-6-chengzhihao1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 8d5fe67..ee678f9 100644 (file)
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1925,21 +1925,13 @@ static int journal_get_superblock(journal_t *journal)
                goto out;
        }
 
-       switch(be32_to_cpu(sb->s_header.h_blocktype)) {
-       case JBD2_SUPERBLOCK_V1:
-               journal->j_format_version = 1;
-               break;
-       case JBD2_SUPERBLOCK_V2:
-               journal->j_format_version = 2;
-               break;
-       default:
+       if (be32_to_cpu(sb->s_header.h_blocktype) != JBD2_SUPERBLOCK_V1 &&
+           be32_to_cpu(sb->s_header.h_blocktype) != JBD2_SUPERBLOCK_V2) {
                printk(KERN_WARNING "JBD2: unrecognised superblock format ID\n");
                goto out;
        }
 
-       if (be32_to_cpu(sb->s_maxlen) < journal->j_total_len)
-               journal->j_total_len = be32_to_cpu(sb->s_maxlen);
-       else if (be32_to_cpu(sb->s_maxlen) > journal->j_total_len) {
+       if (be32_to_cpu(sb->s_maxlen) > journal->j_total_len) {
                printk(KERN_WARNING "JBD2: journal file too short\n");
                goto out;
        }
@@ -1982,25 +1974,14 @@ static int journal_get_superblock(journal_t *journal)
                        journal->j_chksum_driver = NULL;
                        goto out;
                }
-       }
-
-       if (jbd2_journal_has_csum_v2or3(journal)) {
                /* Check superblock checksum */
                if (sb->s_checksum != jbd2_superblock_csum(journal, sb)) {
                        printk(KERN_ERR "JBD2: journal checksum error\n");
                        err = -EFSBADCRC;
                        goto out;
                }
-
-               /* Precompute checksum seed for all metadata */
-               journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid,
-                                                  sizeof(sb->s_uuid));
        }
-
-       journal->j_revoke_records_per_block =
-                               journal_revoke_records_per_block(journal);
        set_buffer_verified(bh);
-
        return 0;
 
 out:
@@ -2025,12 +2006,30 @@ static int load_superblock(journal_t *journal)
 
        sb = journal->j_superblock;
 
+       switch (be32_to_cpu(sb->s_header.h_blocktype)) {
+       case JBD2_SUPERBLOCK_V1:
+               journal->j_format_version = 1;
+               break;
+       case JBD2_SUPERBLOCK_V2:
+               journal->j_format_version = 2;
+               break;
+       }
+
        journal->j_tail_sequence = be32_to_cpu(sb->s_sequence);
        journal->j_tail = be32_to_cpu(sb->s_start);
        journal->j_first = be32_to_cpu(sb->s_first);
        journal->j_errno = be32_to_cpu(sb->s_errno);
        journal->j_last = be32_to_cpu(sb->s_maxlen);
 
+       if (be32_to_cpu(sb->s_maxlen) < journal->j_total_len)
+               journal->j_total_len = be32_to_cpu(sb->s_maxlen);
+       /* Precompute checksum seed for all metadata */
+       if (jbd2_journal_has_csum_v2or3(journal))
+               journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid,
+                                                  sizeof(sb->s_uuid));
+       journal->j_revoke_records_per_block =
+                               journal_revoke_records_per_block(journal);
+
        if (jbd2_has_feature_fast_commit(journal)) {
                journal->j_fc_last = be32_to_cpu(sb->s_maxlen);
                num_fc_blocks = jbd2_journal_get_num_fc_blks(sb);
@@ -2226,8 +2225,7 @@ int jbd2_journal_check_used_features(journal_t *journal, unsigned long compat,
        if (!compat && !ro && !incompat)
                return 1;
        /* Load journal superblock if it is not loaded yet. */
-       if (journal->j_format_version == 0 &&
-           journal_get_superblock(journal) != 0)
+       if (journal_get_superblock(journal))
                return 0;
        if (!jbd2_format_support_feature(journal))
                return 0;