2023-08-11 07:03:31

by Zhang Yi

[permalink] [raw]
Subject: [PATCH v3 01/12] jbd2: move load_superblock() dependent functions

From: Zhang Yi <[email protected]>

Move load_superblock() declaration and the functions it calls before
journal_init_common(). This is a preparation for moving a call to
load_superblock() from jbd2_journal_load() and jbd2_journal_wipe() to
journal_init_common(). No functional changes.

Signed-off-by: Zhang Yi <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
---
fs/jbd2/journal.c | 337 +++++++++++++++++++++++-----------------------
1 file changed, 168 insertions(+), 169 deletions(-)

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index fbce16fedaa4..48c44c7fccf4 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1336,6 +1336,174 @@ static unsigned long jbd2_journal_shrink_count(struct shrinker *shrink,
return count;
}

+/*
+ * If the journal init or create aborts, we need to mark the journal
+ * superblock as being NULL to prevent the journal destroy from writing
+ * back a bogus superblock.
+ */
+static void journal_fail_superblock(journal_t *journal)
+{
+ struct buffer_head *bh = journal->j_sb_buffer;
+ brelse(bh);
+ journal->j_sb_buffer = NULL;
+}
+
+/*
+ * Read the superblock for a given journal, performing initial
+ * validation of the format.
+ */
+static int journal_get_superblock(journal_t *journal)
+{
+ struct buffer_head *bh;
+ journal_superblock_t *sb;
+ int err;
+
+ bh = journal->j_sb_buffer;
+
+ J_ASSERT(bh != NULL);
+ if (buffer_verified(bh))
+ return 0;
+
+ err = bh_read(bh, 0);
+ if (err < 0) {
+ printk(KERN_ERR
+ "JBD2: IO error reading journal superblock\n");
+ goto out;
+ }
+
+ sb = journal->j_superblock;
+
+ err = -EINVAL;
+
+ if (sb->s_header.h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER) ||
+ sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) {
+ printk(KERN_WARNING "JBD2: no valid journal superblock found\n");
+ goto out;
+ }
+
+ 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) {
+ printk(KERN_WARNING "JBD2: journal file too short\n");
+ goto out;
+ }
+
+ if (be32_to_cpu(sb->s_first) == 0 ||
+ be32_to_cpu(sb->s_first) >= journal->j_total_len) {
+ printk(KERN_WARNING
+ "JBD2: Invalid start block of journal: %u\n",
+ be32_to_cpu(sb->s_first));
+ goto out;
+ }
+
+ if (jbd2_has_feature_csum2(journal) &&
+ jbd2_has_feature_csum3(journal)) {
+ /* Can't have checksum v2 and v3 at the same time! */
+ printk(KERN_ERR "JBD2: Can't enable checksumming v2 and v3 "
+ "at the same time!\n");
+ goto out;
+ }
+
+ if (jbd2_journal_has_csum_v2or3_feature(journal) &&
+ jbd2_has_feature_checksum(journal)) {
+ /* Can't have checksum v1 and v2 on at the same time! */
+ printk(KERN_ERR "JBD2: Can't enable checksumming v1 and v2/3 "
+ "at the same time!\n");
+ goto out;
+ }
+
+ if (!jbd2_verify_csum_type(journal, sb)) {
+ printk(KERN_ERR "JBD2: Unknown checksum type\n");
+ goto out;
+ }
+
+ /* Load the checksum driver */
+ if (jbd2_journal_has_csum_v2or3_feature(journal)) {
+ journal->j_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
+ if (IS_ERR(journal->j_chksum_driver)) {
+ printk(KERN_ERR "JBD2: Cannot load crc32c driver.\n");
+ err = PTR_ERR(journal->j_chksum_driver);
+ journal->j_chksum_driver = NULL;
+ goto out;
+ }
+ /* Check superblock checksum */
+ if (sb->s_checksum != jbd2_superblock_csum(journal, sb)) {
+ printk(KERN_ERR "JBD2: journal checksum error\n");
+ err = -EFSBADCRC;
+ goto out;
+ }
+ }
+ set_buffer_verified(bh);
+ return 0;
+
+out:
+ journal_fail_superblock(journal);
+ return err;
+}
+
+static int journal_revoke_records_per_block(journal_t *journal)
+{
+ int record_size;
+ int space = journal->j_blocksize - sizeof(jbd2_journal_revoke_header_t);
+
+ if (jbd2_has_feature_64bit(journal))
+ record_size = 8;
+ else
+ record_size = 4;
+
+ if (jbd2_journal_has_csum_v2or3(journal))
+ space -= sizeof(struct jbd2_journal_block_tail);
+ return space / record_size;
+}
+
+/*
+ * Load the on-disk journal superblock and read the key fields into the
+ * journal_t.
+ */
+static int load_superblock(journal_t *journal)
+{
+ int err;
+ journal_superblock_t *sb;
+ int num_fc_blocks;
+
+ err = journal_get_superblock(journal);
+ if (err)
+ return err;
+
+ sb = journal->j_superblock;
+
+ 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);
+ if (journal->j_last - num_fc_blocks >= JBD2_MIN_JOURNAL_BLOCKS)
+ journal->j_last = journal->j_fc_last - num_fc_blocks;
+ journal->j_fc_first = journal->j_last + 1;
+ journal->j_fc_off = 0;
+ }
+
+ return 0;
+}
+
+
/*
* Management for journal control blocks: functions to create and
* destroy journal_t structures, and to initialise and read existing
@@ -1521,18 +1689,6 @@ journal_t *jbd2_journal_init_inode(struct inode *inode)
return journal;
}

-/*
- * If the journal init or create aborts, we need to mark the journal
- * superblock as being NULL to prevent the journal destroy from writing
- * back a bogus superblock.
- */
-static void journal_fail_superblock(journal_t *journal)
-{
- struct buffer_head *bh = journal->j_sb_buffer;
- brelse(bh);
- journal->j_sb_buffer = NULL;
-}
-
/*
* Given a journal_t structure, initialise the various fields for
* startup of a new journaling session. We use this both when creating
@@ -1889,163 +2045,6 @@ void jbd2_journal_update_sb_errno(journal_t *journal)
}
EXPORT_SYMBOL(jbd2_journal_update_sb_errno);

-static int journal_revoke_records_per_block(journal_t *journal)
-{
- int record_size;
- int space = journal->j_blocksize - sizeof(jbd2_journal_revoke_header_t);
-
- if (jbd2_has_feature_64bit(journal))
- record_size = 8;
- else
- record_size = 4;
-
- if (jbd2_journal_has_csum_v2or3(journal))
- space -= sizeof(struct jbd2_journal_block_tail);
- return space / record_size;
-}
-
-/*
- * Read the superblock for a given journal, performing initial
- * validation of the format.
- */
-static int journal_get_superblock(journal_t *journal)
-{
- struct buffer_head *bh;
- journal_superblock_t *sb;
- int err;
-
- bh = journal->j_sb_buffer;
-
- J_ASSERT(bh != NULL);
- if (buffer_verified(bh))
- return 0;
-
- err = bh_read(bh, 0);
- if (err < 0) {
- printk(KERN_ERR
- "JBD2: IO error reading journal superblock\n");
- goto out;
- }
-
- sb = journal->j_superblock;
-
- err = -EINVAL;
-
- if (sb->s_header.h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER) ||
- sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) {
- printk(KERN_WARNING "JBD2: no valid journal superblock found\n");
- goto out;
- }
-
- 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) {
- printk(KERN_WARNING "JBD2: journal file too short\n");
- goto out;
- }
-
- if (be32_to_cpu(sb->s_first) == 0 ||
- be32_to_cpu(sb->s_first) >= journal->j_total_len) {
- printk(KERN_WARNING
- "JBD2: Invalid start block of journal: %u\n",
- be32_to_cpu(sb->s_first));
- goto out;
- }
-
- if (jbd2_has_feature_csum2(journal) &&
- jbd2_has_feature_csum3(journal)) {
- /* Can't have checksum v2 and v3 at the same time! */
- printk(KERN_ERR "JBD2: Can't enable checksumming v2 and v3 "
- "at the same time!\n");
- goto out;
- }
-
- if (jbd2_journal_has_csum_v2or3_feature(journal) &&
- jbd2_has_feature_checksum(journal)) {
- /* Can't have checksum v1 and v2 on at the same time! */
- printk(KERN_ERR "JBD2: Can't enable checksumming v1 and v2/3 "
- "at the same time!\n");
- goto out;
- }
-
- if (!jbd2_verify_csum_type(journal, sb)) {
- printk(KERN_ERR "JBD2: Unknown checksum type\n");
- goto out;
- }
-
- /* Load the checksum driver */
- if (jbd2_journal_has_csum_v2or3_feature(journal)) {
- journal->j_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
- if (IS_ERR(journal->j_chksum_driver)) {
- printk(KERN_ERR "JBD2: Cannot load crc32c driver.\n");
- err = PTR_ERR(journal->j_chksum_driver);
- journal->j_chksum_driver = NULL;
- goto out;
- }
- /* Check superblock checksum */
- if (sb->s_checksum != jbd2_superblock_csum(journal, sb)) {
- printk(KERN_ERR "JBD2: journal checksum error\n");
- err = -EFSBADCRC;
- goto out;
- }
- }
- set_buffer_verified(bh);
- return 0;
-
-out:
- journal_fail_superblock(journal);
- return err;
-}
-
-/*
- * Load the on-disk journal superblock and read the key fields into the
- * journal_t.
- */
-
-static int load_superblock(journal_t *journal)
-{
- int err;
- journal_superblock_t *sb;
- int num_fc_blocks;
-
- err = journal_get_superblock(journal);
- if (err)
- return err;
-
- sb = journal->j_superblock;
-
- 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);
- if (journal->j_last - num_fc_blocks >= JBD2_MIN_JOURNAL_BLOCKS)
- journal->j_last = journal->j_fc_last - num_fc_blocks;
- journal->j_fc_first = journal->j_last + 1;
- journal->j_fc_off = 0;
- }
-
- return 0;
-}
-
-
/**
* jbd2_journal_load() - Read journal from disk.
* @journal: Journal to act on.
--
2.34.3