diff options
Diffstat (limited to 'fs/jbd2')
| -rw-r--r-- | fs/jbd2/journal.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 1afb701622b..63175f9391a 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -97,6 +97,15 @@ EXPORT_SYMBOL(jbd2_inode_cache); static void __journal_abort_soft (journal_t *journal, int errno); static int jbd2_journal_create_slab(size_t slab_size); +/* Checksumming functions */ +int jbd2_verify_csum_type(journal_t *j, journal_superblock_t *sb) +{ + if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) + return 1; + + return sb->s_checksum_type == JBD2_CRC32C_CHKSUM; +} + /* * Helper function used to manage commit timeouts */ @@ -1376,6 +1385,9 @@ static int journal_get_superblock(journal_t *journal) } } + if (buffer_verified(bh)) + return 0; + sb = journal->j_superblock; err = -EINVAL; @@ -1413,6 +1425,21 @@ static int journal_get_superblock(journal_t *journal) goto out; } + if (JBD2_HAS_COMPAT_FEATURE(journal, JBD2_FEATURE_COMPAT_CHECKSUM) && + JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2)) { + /* Can't have checksum v1 and v2 on at the same time! */ + printk(KERN_ERR "JBD: Can't enable checksumming v1 and v2 " + "at the same time!\n"); + goto out; + } + + if (!jbd2_verify_csum_type(journal, sb)) { + printk(KERN_ERR "JBD: Unknown checksum type\n"); + goto out; + } + + set_buffer_verified(bh); + return 0; out: @@ -1653,6 +1680,10 @@ int jbd2_journal_check_available_features (journal_t *journal, unsigned long com int jbd2_journal_set_features (journal_t *journal, unsigned long compat, unsigned long ro, unsigned long incompat) { +#define INCOMPAT_FEATURE_ON(f) \ + ((incompat & (f)) && !(sb->s_feature_incompat & cpu_to_be32(f))) +#define COMPAT_FEATURE_ON(f) \ + ((compat & (f)) && !(sb->s_feature_compat & cpu_to_be32(f))) journal_superblock_t *sb; if (jbd2_journal_check_used_features(journal, compat, ro, incompat)) @@ -1661,16 +1692,35 @@ int jbd2_journal_set_features (journal_t *journal, unsigned long compat, if (!jbd2_journal_check_available_features(journal, compat, ro, incompat)) return 0; + /* Asking for checksumming v2 and v1? Only give them v2. */ + if (incompat & JBD2_FEATURE_INCOMPAT_CSUM_V2 && + compat & JBD2_FEATURE_COMPAT_CHECKSUM) + compat &= ~JBD2_FEATURE_COMPAT_CHECKSUM; + jbd_debug(1, "Setting new features 0x%lx/0x%lx/0x%lx\n", compat, ro, incompat); sb = journal->j_superblock; + /* If enabling v2 checksums, update superblock */ + if (INCOMPAT_FEATURE_ON(JBD2_FEATURE_INCOMPAT_CSUM_V2)) { + sb->s_checksum_type = JBD2_CRC32C_CHKSUM; + sb->s_feature_compat &= + ~cpu_to_be32(JBD2_FEATURE_COMPAT_CHECKSUM); + } + + /* If enabling v1 checksums, downgrade superblock */ + if (COMPAT_FEATURE_ON(JBD2_FEATURE_COMPAT_CHECKSUM)) + sb->s_feature_incompat &= + ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_CSUM_V2); + sb->s_feature_compat |= cpu_to_be32(compat); sb->s_feature_ro_compat |= cpu_to_be32(ro); sb->s_feature_incompat |= cpu_to_be32(incompat); return 1; +#undef COMPAT_FEATURE_ON +#undef INCOMPAT_FEATURE_ON } /* |