ref: 7e64817a1cf30c6ce31a9a23ab3301dc5fa3056b
parent: fbfb8e6fbaf7833a851b713efa31f0085ea0cc60
author: ngkaho1234 <ngkaho1234@gmail.com>
date: Fri Jan 1 08:48:10 EST 2016
ext4_journal: initial support of journal checksumming is added.
--- a/lwext4/ext4_journal.c
+++ b/lwext4/ext4_journal.c
@@ -118,6 +118,209 @@
#define jbd_alloc_revoke_entry() calloc(1, sizeof(struct revoke_entry))
#define jbd_free_revoke_entry(addr) free(addr)
+static int jbd_has_csum(struct jbd_sb *jbd_sb)
+{+ if (JBD_HAS_INCOMPAT_FEATURE(jbd_sb, JBD_FEATURE_INCOMPAT_CSUM_V2))
+ return 2;
+
+ if (JBD_HAS_INCOMPAT_FEATURE(jbd_sb, JBD_FEATURE_INCOMPAT_CSUM_V3))
+ return 3;
+
+ return 0;
+}
+
+#if CONFIG_META_CSUM_ENABLE
+static uint32_t jbd_sb_csum(struct jbd_sb *jbd_sb)
+{+ uint32_t checksum = 0;
+
+ if (jbd_has_csum(jbd_sb)) {+ uint32_t orig_checksum = jbd_sb->checksum;
+ jbd_set32(jbd_sb, checksum, 0);
+ /* Calculate crc32c checksum against tho whole superblock */
+ checksum = ext4_crc32c(EXT4_CRC32_INIT, jbd_sb,
+ JBD_SUPERBLOCK_SIZE);
+ jbd_sb->checksum = orig_checksum;
+ }
+ return checksum;
+}
+#else
+#define jbd_sb_csum(...) 0
+#endif
+
+static void jbd_sb_csum_set(struct jbd_sb *jbd_sb)
+{+ if (!jbd_has_csum(jbd_sb))
+ return;
+
+ jbd_set32(jbd_sb, checksum, jbd_sb_csum(jbd_sb));
+}
+
+#if CONFIG_META_CSUM_ENABLE
+static bool
+jbd_verify_sb_csum(struct jbd_sb *jbd_sb)
+{+ if (!jbd_has_csum(jbd_sb))
+ return true;
+
+ return jbd_sb_csum(jbd_sb) == jbd_get32(jbd_sb, checksum);
+}
+#else
+#define jbd_verify_sb_csum(...) true
+#endif
+
+#if CONFIG_META_CSUM_ENABLE
+static uint32_t jbd_meta_csum(struct jbd_fs *jbd_fs,
+ struct jbd_bhdr *bhdr)
+{+ uint32_t checksum = 0;
+
+ if (jbd_has_csum(&jbd_fs->sb)) {+ uint32_t block_size = jbd_get32(&jbd_fs->sb, blocksize);
+ struct jbd_block_tail *tail =
+ (struct jbd_block_tail *)((char *)bhdr + block_size -
+ sizeof(struct jbd_block_tail));
+ uint32_t orig_checksum = tail->checksum;
+ tail->checksum = 0;
+
+ /* First calculate crc32c checksum against fs uuid */
+ checksum = ext4_crc32c(EXT4_CRC32_INIT, jbd_fs->sb.uuid,
+ sizeof(jbd_fs->sb.uuid));
+ /* Calculate crc32c checksum against tho whole block */
+ checksum = ext4_crc32(checksum, bhdr,
+ block_size);
+ tail->checksum = orig_checksum;
+ }
+ return checksum;
+}
+#else
+#define jbd_meta_csum(...) 0
+#endif
+
+static void jbd_meta_csum_set(struct jbd_fs *jbd_fs,
+ struct jbd_bhdr *bhdr)
+{+ uint32_t block_size = jbd_get32(&jbd_fs->sb, blocksize);
+ struct jbd_block_tail *tail = (struct jbd_block_tail *)
+ ((char *)bhdr + block_size -
+ sizeof(struct jbd_block_tail));
+ if (!jbd_has_csum(&jbd_fs->sb))
+ return;
+
+ tail->checksum = to_be32(jbd_meta_csum(jbd_fs, bhdr));
+}
+
+#if CONFIG_META_CSUM_ENABLE
+static bool
+jbd_verify_meta_csum(struct jbd_fs *jbd_fs,
+ struct jbd_bhdr *bhdr)
+{+ uint32_t block_size = jbd_get32(&jbd_fs->sb, blocksize);
+ struct jbd_block_tail *tail = (struct jbd_block_tail *)
+ ((char *)bhdr + block_size -
+ sizeof(struct jbd_block_tail));
+ if (!jbd_has_csum(&jbd_fs->sb))
+ return true;
+
+ return jbd_meta_csum(jbd_fs, bhdr) == to_be32(tail->checksum);
+}
+#else
+#define jbd_verify_meta_csum(...) true
+#endif
+
+#if CONFIG_META_CSUM_ENABLE
+static uint32_t jbd_commit_csum(struct jbd_fs *jbd_fs,
+ struct jbd_commit_header *header)
+{+ uint32_t checksum = 0;
+
+ if (jbd_has_csum(&jbd_fs->sb)) {+ uint32_t orig_checksum_type = header->chksum_type,
+ orig_checksum_size = header->chksum_size,
+ orig_checksum = header->chksum[0];
+ uint32_t block_size = jbd_get32(&jbd_fs->sb, blocksize);
+ header->chksum_type = 0;
+ header->chksum_size = 0;
+ header->chksum[0] = 0;
+
+ /* First calculate crc32c checksum against fs uuid */
+ checksum = ext4_crc32c(EXT4_CRC32_INIT, jbd_fs->sb.uuid,
+ sizeof(jbd_fs->sb.uuid));
+ /* Calculate crc32c checksum against tho whole block */
+ checksum = ext4_crc32(checksum, header,
+ block_size);
+
+ header->chksum_type = orig_checksum_type;
+ header->chksum_size = orig_checksum_size;
+ header->chksum[0] = orig_checksum;
+ }
+ return checksum;
+}
+#else
+#define jbd_commit_csum(...) 0
+#endif
+
+static void jbd_commit_csum_set(struct jbd_fs *jbd_fs,
+ struct jbd_commit_header *header)
+{+ if (!jbd_has_csum(&jbd_fs->sb))
+ return;
+
+ header->chksum_type = 0;
+ header->chksum_size = 0;
+ header->chksum[0] = jbd_commit_csum(jbd_fs, header);
+}
+
+#if CONFIG_META_CSUM_ENABLE
+static bool jbd_verify_commit_csum(struct jbd_fs *jbd_fs,
+ struct jbd_commit_header *header)
+{+ if (!jbd_has_csum(&jbd_fs->sb))
+ return true;
+
+ return header->chksum[0] == to_be32(jbd_commit_csum(jbd_fs,
+ header));
+}
+#else
+#define jbd_verify_commit_csum(...) true
+#endif
+
+#if CONFIG_META_CSUM_ENABLE
+static uint32_t jbd_block_csum(struct jbd_fs *jbd_fs, const void *buf)
+{+ uint32_t checksum = 0;
+
+ if (jbd_has_csum(&jbd_fs->sb)) {+ uint32_t block_size = jbd_get32(&jbd_fs->sb, blocksize);
+ /* First calculate crc32c checksum against fs uuid */
+ checksum = ext4_crc32c(EXT4_CRC32_INIT, jbd_fs->sb.uuid,
+ sizeof(jbd_fs->sb.uuid));
+ /* Calculate crc32c checksum against tho whole block */
+ checksum = ext4_crc32(checksum, buf,
+ block_size);
+ }
+ return checksum;
+}
+#else
+#define jbd_block_csum(...) 0
+#endif
+
+static void jbd_block_tag_csum_set(struct jbd_fs *jbd_fs, void *__tag,
+ uint32_t checksum)
+{+ int ver = jbd_has_csum(&jbd_fs->sb);
+ if (!ver)
+ return;
+
+ if (ver == 2) {+ struct jbd_block_tag *tag = __tag;
+ tag->checksum = (uint16_t)to_be32(checksum);
+ } else {+ struct jbd_block_tag3 *tag = __tag;
+ tag->checksum = to_be32(checksum);
+ }
+}
+
/**@brief Write jbd superblock to disk.
* @param jbd_fs jbd filesystem
* @param s jbd superblock
@@ -132,6 +335,7 @@
if (rc != EOK)
return rc;
+ jbd_sb_csum_set(s);
offset = fblock * ext4_sb_get_block_size(&fs->sb);
return ext4_block_writebytes(fs->bdev, offset, s,
EXT4_SUPERBLOCK_SIZE);
@@ -169,7 +373,7 @@
jbd_get32(header, blocktype) != JBD_SUPERBLOCK_V2)
return false;
- return true;
+ return jbd_verify_sb_csum(sb);
}
/**@brief Write back dirty jbd superblock to disk.
@@ -373,6 +577,9 @@
/**@brief Is this the last tag? */
bool last_tag;
+
+ /**@brief crc32c checksum. */
+ uint32_t checksum;
};
/**@brief Extract information from a block tag.
@@ -493,6 +700,8 @@
jbd_set32(tag, flags,
jbd_get32(tag, flags) | JBD_FLAG_SAME_UUID);
+ jbd_block_tag_csum_set(jbd_fs, __tag, tag_info->checksum);
+
if (tag_info->last_tag)
jbd_set32(tag, flags,
jbd_get32(tag, flags) | JBD_FLAG_LAST_TAG);
@@ -517,6 +726,8 @@
jbd_set16(tag, flags,
jbd_get16(tag, flags) | JBD_FLAG_SAME_UUID);
+ jbd_block_tag_csum_set(jbd_fs, __tag, tag_info->checksum);
+
if (tag_info->last_tag)
jbd_set16(tag, flags,
jbd_get16(tag, flags) | JBD_FLAG_LAST_TAG);
@@ -845,6 +1056,14 @@
switch (jbd_get32(header, blocktype)) {case JBD_DESCRIPTOR_BLOCK:
+ if (!jbd_verify_meta_csum(jbd_fs, header)) {+ ext4_dbg(DEBUG_JBD,
+ DBG_WARN "Descriptor block checksum failed."
+ "Journal block: %" PRIu32"\n",
+ this_block);
+ log_end = true;
+ break;
+ }
ext4_dbg(DEBUG_JBD, "Descriptor block: %" PRIu32", "
"trans_id: %" PRIu32"\n",
this_block, this_trans_id);
@@ -862,6 +1081,15 @@
break;
case JBD_COMMIT_BLOCK:
+ if (!jbd_verify_commit_csum(jbd_fs,
+ (struct jbd_commit_header *)header)) {+ ext4_dbg(DEBUG_JBD,
+ DBG_WARN "Commit block checksum failed."
+ "Journal block: %" PRIu32"\n",
+ this_block);
+ log_end = true;
+ break;
+ }
ext4_dbg(DEBUG_JBD, "Commit block: %" PRIu32", "
"trans_id: %" PRIu32"\n",
this_block, this_trans_id);
@@ -871,6 +1099,14 @@
this_trans_id++;
break;
case JBD_REVOKE_BLOCK:
+ if (!jbd_verify_meta_csum(jbd_fs, header)) {+ ext4_dbg(DEBUG_JBD,
+ DBG_WARN "Revoke block checksum failed."
+ "Journal block: %" PRIu32"\n",
+ this_block);
+ log_end = true;
+ break;
+ }
ext4_dbg(DEBUG_JBD, "Revoke block: %" PRIu32", "
"trans_id: %" PRIu32"\n",
this_block, this_trans_id);
@@ -1375,6 +1611,7 @@
jbd_set32(&header->header, blocktype, JBD_COMMIT_BLOCK);
jbd_set32(&header->header, sequence, trans->trans_id);
+ jbd_commit_csum_set(journal->jbd_fs, header);
ext4_bcache_set_dirty(commit_block.buf);
rc = jbd_block_set(journal->jbd_fs, &commit_block);
if (rc != EOK)
@@ -1424,6 +1661,7 @@
TAILQ_FOREACH_SAFE(jbd_buf, &trans->buf_queue, buf_node, tmp) {struct tag_info tag_info;
bool uuid_exist = false;
+ uint32_t checksum;
if (!ext4_bcache_test_flag(jbd_buf->block.buf,
BC_DIRTY)) {/* The buffer has not been modified, just release
@@ -1439,6 +1677,8 @@
free(jbd_buf);
continue;
}
+ checksum = jbd_block_csum(journal->jbd_fs,
+ jbd_buf->block.data);
again:
if (!desc_iblock) {struct jbd_bhdr *bhdr;
@@ -1461,6 +1701,9 @@
tag_tbl_size = journal->block_size -
sizeof(struct jbd_bhdr);
+ if (jbd_has_csum(&journal->jbd_fs->sb))
+ tag_tbl_size -= sizeof(struct jbd_block_tail);
+
if (!trans->start_iblock)
trans->start_iblock = desc_iblock;
@@ -1471,6 +1714,7 @@
tag_info.last_tag = true;
else
tag_info.last_tag = false;
+ tag_info.checksum = checksum;
if (uuid_exist)
memcpy(tag_info.uuid, journal->jbd_fs->sb.uuid,
@@ -1481,6 +1725,8 @@
tag_tbl_size,
&tag_info);
if (rc != EOK) {+ jbd_meta_csum_set(journal->jbd_fs,
+ (struct jbd_bhdr *)desc_block.data);
jbd_block_set(journal->jbd_fs, &desc_block);
desc_iblock = 0;
goto again;
@@ -1506,8 +1752,11 @@
i++;
}
- if (rc == EOK && desc_iblock)
+ if (rc == EOK && desc_iblock) {+ jbd_meta_csum_set(journal->jbd_fs,
+ (struct jbd_bhdr *)desc_block.data);
jbd_block_set(journal->jbd_fs, &desc_block);
+ }
return rc;
}
@@ -1557,6 +1806,9 @@
tag_tbl_size = journal->block_size -
sizeof(struct jbd_revoke_header);
+ if (jbd_has_csum(&journal->jbd_fs->sb))
+ tag_tbl_size -= sizeof(struct jbd_block_tail);
+
if (!trans->start_iblock)
trans->start_iblock = desc_iblock;
@@ -1565,6 +1817,8 @@
if (tag_tbl_size < record_len) {jbd_set32(header, count,
journal->block_size - tag_tbl_size);
+ jbd_meta_csum_set(journal->jbd_fs,
+ (struct jbd_bhdr *)desc_block.data);
jbd_block_set(journal->jbd_fs, &desc_block);
desc_iblock = 0;
header = NULL;
@@ -1589,6 +1843,8 @@
jbd_set32(header, count,
journal->block_size - tag_tbl_size);
+ jbd_meta_csum_set(journal->jbd_fs,
+ (struct jbd_bhdr *)desc_block.data);
jbd_block_set(journal->jbd_fs, &desc_block);
}