ref: 534f9cba3aa9390d485275431f2165cda34bd876
parent: ce4eae952d8a1eab8ebe3a168e7e3a791bab9607
author: ngkaho1234 <ngkaho1234@gmail.com>
date: Sat Nov 28 09:51:21 EST 2015
ext4_journal: initial support of processing block_tags array.
--- a/lwext4/ext4_journal.c
+++ b/lwext4/ext4_journal.c
@@ -11,8 +11,10 @@
#include "ext4_blockdev.h"
#include "ext4_crc32c.h"
#include "ext4_debug.h"
+#include "tree.h"
#include <string.h>
+#include <malloc.h>
int jbd_inode_bmap(struct jbd_fs *jbd_fs,
ext4_lblk_t iblock,
@@ -50,12 +52,12 @@
static bool jbd_verify_sb(struct jbd_sb *sb)
{- struct jbd_bhdr *bhdr = &sb->header;
- if (bhdr->magic != to_be32(JBD_MAGIC_NUMBER))
+ struct jbd_bhdr *header = &sb->header;
+ if (jbd_get32(header, magic) != JBD_MAGIC_NUMBER)
return false;
- if (bhdr->blocktype != to_be32(JBD_SUPERBLOCK) &&
- bhdr->blocktype != to_be32(JBD_SUPERBLOCK_V2))
+ if (jbd_get32(header, blocktype) != JBD_SUPERBLOCK &&
+ jbd_get32(header, blocktype) != JBD_SUPERBLOCK_V2)
return false;
return true;
@@ -146,11 +148,154 @@
block);
}
+/*
+ * helper functions to deal with 32 or 64bit block numbers.
+ */
+int jbd_tag_bytes(struct jbd_fs *jbd_fs)
+{+ int size;
+
+ if (JBD_HAS_INCOMPAT_FEATURE(&jbd_fs->sb,
+ JBD_FEATURE_INCOMPAT_CSUM_V3))
+ return sizeof(struct jbd_block_tag3);
+
+ size = sizeof(struct jbd_block_tag);
+
+ if (JBD_HAS_INCOMPAT_FEATURE(&jbd_fs->sb,
+ JBD_FEATURE_INCOMPAT_CSUM_V2))
+ size += sizeof(uint16_t);
+
+ if (JBD_HAS_INCOMPAT_FEATURE(&jbd_fs->sb,
+ JBD_FEATURE_INCOMPAT_64BIT))
+ return size;
+
+ return size - sizeof(uint32_t);
+}
+
+static void
+jbd_extract_block_tag(struct jbd_fs *jbd_fs,
+ uint32_t tag_bytes,
+ void *__tag,
+ ext4_fsblk_t *block,
+ bool *uuid_exist,
+ uint8_t *uuid,
+ bool *last_tag)
+{+ char *uuid_start;
+ *uuid_exist = false;
+ *last_tag = false;
+ if (JBD_HAS_INCOMPAT_FEATURE(&jbd_fs->sb,
+ JBD_FEATURE_INCOMPAT_CSUM_V3)) {+ struct jbd_block_tag3 *tag = __tag;
+ *block = jbd_get32(tag, blocknr);
+ if (JBD_HAS_INCOMPAT_FEATURE(&jbd_fs->sb,
+ JBD_FEATURE_INCOMPAT_64BIT))
+ *block |= (uint64_t)jbd_get32(tag, blocknr_high) << 32;
+
+ if (jbd_get32(tag, flags) & JBD_FLAG_ESCAPE)
+ *block = 0;
+
+ if (!(jbd_get32(tag, flags) & JBD_FLAG_SAME_UUID)) {+ uuid_start = (char *)tag + tag_bytes;
+ *uuid_exist = true;
+ memcpy(uuid, uuid_start, UUID_SIZE);
+ }
+
+ if (jbd_get32(tag, flags) & JBD_FLAG_LAST_TAG)
+ *last_tag = true;
+
+ } else {+ struct jbd_block_tag *tag = __tag;
+ *block = jbd_get32(tag, blocknr);
+ if (JBD_HAS_INCOMPAT_FEATURE(&jbd_fs->sb,
+ JBD_FEATURE_INCOMPAT_64BIT))
+ *block |= (uint64_t)jbd_get32(tag, blocknr_high) << 32;
+
+ if (jbd_get32(tag, flags) & JBD_FLAG_ESCAPE)
+ *block = 0;
+
+ if (!(jbd_get32(tag, flags) & JBD_FLAG_SAME_UUID)) {+ uuid_start = (char *)tag + tag_bytes;
+ *uuid_exist = true;
+ memcpy(uuid, uuid_start, UUID_SIZE);
+ }
+
+ if (jbd_get32(tag, flags) & JBD_FLAG_LAST_TAG)
+ *last_tag = true;
+
+ }
+}
+
+static void
+jbd_iterate_block_table(struct jbd_fs *jbd_fs,
+ void *__tag_start,
+ uint32_t tag_tbl_size,
+ void (*func)(struct jbd_fs * jbd_fs,
+ ext4_fsblk_t block,
+ uint8_t *uuid,
+ void *arg),
+ void *arg)
+{+ ext4_fsblk_t block = 0;
+ uint8_t uuid[UUID_SIZE];
+ char *tag_start, *tag_ptr;
+ uint32_t tag_bytes = jbd_tag_bytes(jbd_fs);
+ tag_start = __tag_start;
+ tag_ptr = tag_start;
+
+ if (JBD_HAS_INCOMPAT_FEATURE(&jbd_fs->sb,
+ JBD_FEATURE_INCOMPAT_CSUM_V2) ||
+ JBD_HAS_INCOMPAT_FEATURE(&jbd_fs->sb,
+ JBD_FEATURE_INCOMPAT_CSUM_V3))
+ tag_tbl_size -= sizeof(struct jbd_block_tail);
+
+ while (tag_ptr - tag_start + tag_bytes <= tag_tbl_size) {+ bool uuid_exist;
+ bool last_tag;
+ jbd_extract_block_tag(jbd_fs,
+ tag_bytes,
+ tag_ptr,
+ &block,
+ &uuid_exist,
+ uuid,
+ &last_tag);
+ if (func)
+ func(jbd_fs, block, uuid, arg);
+
+ if (last_tag)
+ break;
+
+ tag_ptr += tag_bytes;
+ if (uuid_exist)
+ tag_ptr += UUID_SIZE;
+
+ }
+}
+
+static void jbd_display_block_tags(struct jbd_fs *jbd_fs,
+ ext4_fsblk_t block,
+ uint8_t *uuid,
+ void *arg)
+{+ uint32_t *iblock = arg;
+ ext4_dbg(DEBUG_JBD, "Block in block_tag: %" PRIu64 "\n", block);
+ (*iblock)++;
+ (void)jbd_fs;
+ (void)uuid;
+ return;
+}
+
+struct revoke_entry {+ ext4_fsblk_t block;
+ uint32_t trans_id;
+ RB_ENTRY(revoke_entry) revoke_node;
+};
+
/* Make sure we wrap around the log correctly! */
#define wrap(sb, var) \
do { \- if (var >= to_be32((sb)->maxlen)) \
- var -= (to_be32((sb)->maxlen) - to_be32((sb)->first)); \
+ if (var >= jbd_get32((sb), maxlen)) \
+ var -= (jbd_get32((sb), maxlen) - jbd_get32((sb), first)); \
} while (0)
#define ACTION_SCAN 0
@@ -160,8 +305,38 @@
struct recover_info {uint32_t start_trans_id;
uint32_t last_trans_id;
+ RB_HEAD(jbd_revoke, revoke_entry) revoke_root;
};
+static void jbd_build_revoke_root(struct jbd_fs *jbd_fs,
+ struct jbd_bhdr *header,
+ struct recover_info *info)
+{+ struct jbd_revoke_header *revoke_hdr =
+ (struct jbd_revoke_header *)header;
+
+ jbd_iterate_block_table(jbd_fs,
+ revoke_hdr + 1,
+ jbd_get32(&jbd_fs->sb, blocksize) -
+ sizeof(struct jbd_revoke_header),
+ jbd_display_block_tags,
+ NULL);
+
+ (void)info;
+}
+
+static void jbd_debug_descriptor_block(struct jbd_fs *jbd_fs,
+ struct jbd_bhdr *header,
+ uint32_t *iblock)
+{+ jbd_iterate_block_table(jbd_fs,
+ header,
+ jbd_get32(&jbd_fs->sb, blocksize) -
+ sizeof(struct jbd_bhdr),
+ jbd_display_block_tags,
+ iblock);
+}
+
int jbd_iterate_log(struct jbd_fs *jbd_fs,
struct recover_info *info,
int action)
@@ -172,8 +347,8 @@
uint32_t start_trans_id, this_trans_id;
uint32_t start_block, this_block;
- start_trans_id = this_trans_id = to_be32(sb->sequence);
- start_block = this_block = to_be32(sb->start);
+ start_trans_id = this_trans_id = jbd_get32(sb, sequence);
+ start_block = this_block = jbd_get32(sb, start);
ext4_dbg(DEBUG_JBD, "Start of journal at trans id: %" PRIu32 "\n",
start_trans_id);
@@ -192,14 +367,14 @@
break;
header = (struct jbd_bhdr *)block.data;
- if (header->magic != to_be32(JBD_MAGIC_NUMBER)) {+ if (jbd_get32(header, magic) != JBD_MAGIC_NUMBER) {jbd_block_set(jbd_fs, &block);
log_end = true;
continue;
}
- if (header->sequence != to_be32(this_trans_id)) {- if (this_trans_id <= info->last_trans_id)
+ if (jbd_get32(header, sequence) != this_trans_id) {+ if (action != ACTION_SCAN)
r = EIO;
jbd_block_set(jbd_fs, &block);
@@ -207,11 +382,12 @@
continue;
}
- switch (header->blocktype) {+ switch (jbd_get32(header, blocktype)) {case JBD_DESCRIPTOR_BLOCK:
ext4_dbg(DEBUG_JBD, "Descriptor block: %u, "
"trans_id: %u\n",
this_block, this_trans_id);
+ jbd_debug_descriptor_block(jbd_fs, header, &this_block);
break;
case JBD_COMMIT_BLOCK:
ext4_dbg(DEBUG_JBD, "Commit block: %u, "
@@ -223,6 +399,7 @@
ext4_dbg(DEBUG_JBD, "Revoke block: %u, "
"trans_id: %u\n",
this_block, this_trans_id);
+ jbd_build_revoke_root(jbd_fs, header, info);
break;
default:
log_end = true;
--- a/lwext4/ext4_types.h
+++ b/lwext4/ext4_types.h
@@ -976,6 +976,12 @@
uint32_t blocknr_high; /* most-significant high 32bits. */
};
+/* Definitions for the journal tag flags word: */
+#define JBD_FLAG_ESCAPE 1 /* on-disk block is escaped */
+#define JBD_FLAG_SAME_UUID 2 /* block has same uuid as previous */
+#define JBD_FLAG_DELETED 4 /* block deleted by this transaction */
+#define JBD_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
+
/* Tail of descriptor block, for checksumming */
struct jbd_block_tail {uint32_t checksum;
@@ -1154,6 +1160,23 @@
(s, f, v) do { (s)->f = (v); } \while (0)
+/****************************Access macros to jbd2 structures*****************/
+
+#define jbd_get32(s, f) to_be32((s)->f)
+#define jbd_get16(s, f) to_be16((s)->f)
+#define jbd_get8(s, f) (s)->f
+
+#define jbd_set32(s, f, v) \
+ do { \+ (s)->f = to_be32(v); \
+ } while (0)
+#define jbd_set16(s, f, v) \
+ do { \+ (s)->f = to_be16(v); \
+ } while (0)
+#define jbd_set8 \
+ (s, f, v) do { (s)->f = (v); } \+ while (0)
#ifdef __GNUC__
#ifndef __unused