[PATCH] 64-bit jbd2 core
Here is the patch to JBD to handle 64 bit block numbers, originally from Zach
Brown. This patch is useful only after adding support for 64-bit block
numbers in the filesystem.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index b1a4eaf..44d68a1 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -271,6 +271,14 @@
journal_do_submit_data(wbuf, bufs);
}
+static inline void write_tag_block(int tag_bytes, journal_block_tag_t *tag,
+ sector_t block)
+{
+ tag->t_blocknr = cpu_to_be32(block & (u32)~0);
+ if (tag_bytes > JBD_TAG_SIZE32)
+ tag->t_blocknr_high = cpu_to_be32((block >> 31) >> 1);
+}
+
/*
* jbd2_journal_commit_transaction
*
@@ -293,6 +301,7 @@
int first_tag = 0;
int tag_flag;
int i;
+ int tag_bytes = journal_tag_bytes(journal);
/*
* First job: lock down the current transaction and wait for
@@ -597,10 +606,10 @@
tag_flag |= JBD2_FLAG_SAME_UUID;
tag = (journal_block_tag_t *) tagp;
- tag->t_blocknr = cpu_to_be32(jh2bh(jh)->b_blocknr);
+ write_tag_block(tag_bytes, tag, jh2bh(jh)->b_blocknr);
tag->t_flags = cpu_to_be32(tag_flag);
- tagp += sizeof(journal_block_tag_t);
- space_left -= sizeof(journal_block_tag_t);
+ tagp += tag_bytes;
+ space_left -= tag_bytes;
if (first_tag) {
memcpy (tagp, journal->j_uuid, 16);
@@ -614,7 +623,7 @@
if (bufs == journal->j_wbufsize ||
commit_transaction->t_buffers == NULL ||
- space_left < sizeof(journal_block_tag_t) + 16) {
+ space_left < tag_bytes + 16) {
jbd_debug(4, "JBD: Submit %d IOs\n", bufs);
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 8d0f71e..926ebcb 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1610,6 +1610,17 @@
}
/*
+ * helper functions to deal with 32 or 64bit block numbers.
+ */
+size_t journal_tag_bytes(journal_t *journal)
+{
+ if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT))
+ return JBD_TAG_SIZE64;
+ else
+ return JBD_TAG_SIZE32;
+}
+
+/*
* Simple support for retrying memory allocations. Introduced to help to
* debug different VM deadlock avoidance strategies.
*/
diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c
index b2012d1..2486843 100644
--- a/fs/jbd2/recovery.c
+++ b/fs/jbd2/recovery.c
@@ -178,19 +178,20 @@
* Count the number of in-use tags in a journal descriptor block.
*/
-static int count_tags(struct buffer_head *bh, int size)
+static int count_tags(journal_t *journal, struct buffer_head *bh)
{
char * tagp;
journal_block_tag_t * tag;
- int nr = 0;
+ int nr = 0, size = journal->j_blocksize;
+ int tag_bytes = journal_tag_bytes(journal);
tagp = &bh->b_data[sizeof(journal_header_t)];
- while ((tagp - bh->b_data + sizeof(journal_block_tag_t)) <= size) {
+ while ((tagp - bh->b_data + tag_bytes) <= size) {
tag = (journal_block_tag_t *) tagp;
nr++;
- tagp += sizeof(journal_block_tag_t);
+ tagp += tag_bytes;
if (!(tag->t_flags & cpu_to_be32(JBD2_FLAG_SAME_UUID)))
tagp += 16;
@@ -307,6 +308,14 @@
return err;
}
+static inline sector_t read_tag_block(int tag_bytes, journal_block_tag_t *tag)
+{
+ sector_t block = be32_to_cpu(tag->t_blocknr);
+ if (tag_bytes > JBD_TAG_SIZE32)
+ block |= (u64)be32_to_cpu(tag->t_blocknr_high) << 32;
+ return block;
+}
+
static int do_one_pass(journal_t *journal,
struct recovery_info *info, enum passtype pass)
{
@@ -318,11 +327,12 @@
struct buffer_head * bh;
unsigned int sequence;
int blocktype;
+ int tag_bytes = journal_tag_bytes(journal);
/* Precompute the maximum metadata descriptors in a descriptor block */
int MAX_BLOCKS_PER_DESC;
MAX_BLOCKS_PER_DESC = ((journal->j_blocksize-sizeof(journal_header_t))
- / sizeof(journal_block_tag_t));
+ / tag_bytes);
/*
* First thing is to establish what we expect to find in the log
@@ -412,8 +422,7 @@
* in pass REPLAY; otherwise, just skip over the
* blocks it describes. */
if (pass != PASS_REPLAY) {
- next_log_block +=
- count_tags(bh, journal->j_blocksize);
+ next_log_block += count_tags(journal, bh);
wrap(journal, next_log_block);
brelse(bh);
continue;
@@ -424,7 +433,7 @@
* getting done here! */
tagp = &bh->b_data[sizeof(journal_header_t)];
- while ((tagp - bh->b_data +sizeof(journal_block_tag_t))
+ while ((tagp - bh->b_data + tag_bytes)
<= journal->j_blocksize) {
unsigned long io_block;
@@ -446,7 +455,8 @@
unsigned long blocknr;
J_ASSERT(obh != NULL);
- blocknr = be32_to_cpu(tag->t_blocknr);
+ blocknr = read_tag_block(tag_bytes,
+ tag);
/* If the block has been
* revoked, then we're all done
@@ -494,7 +504,7 @@
}
skip_write:
- tagp += sizeof(journal_block_tag_t);
+ tagp += tag_bytes;
if (!(flags & JBD2_FLAG_SAME_UUID))
tagp += 16;
@@ -572,17 +582,24 @@
{
jbd2_journal_revoke_header_t *header;
int offset, max;
+ int record_len = 4;
header = (jbd2_journal_revoke_header_t *) bh->b_data;
offset = sizeof(jbd2_journal_revoke_header_t);
max = be32_to_cpu(header->r_count);
- while (offset < max) {
+ if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT))
+ record_len = 8;
+
+ while (offset + record_len <= max) {
unsigned long blocknr;
int err;
- blocknr = be32_to_cpu(* ((__be32 *) (bh->b_data+offset)));
- offset += 4;
+ if (record_len == 4)
+ blocknr = be32_to_cpu(* ((__be32 *) (bh->b_data+offset)));
+ else
+ blocknr = be64_to_cpu(* ((__be64 *) (bh->b_data+offset)));
+ offset += record_len;
err = jbd2_journal_set_revoke(journal, blocknr, sequence);
if (err)
return err;
diff --git a/fs/jbd2/revoke.c b/fs/jbd2/revoke.c
index 5820a0c..8aac875 100644
--- a/fs/jbd2/revoke.c
+++ b/fs/jbd2/revoke.c
@@ -584,9 +584,17 @@
*descriptorp = descriptor;
}
- * ((__be32 *)(&jh2bh(descriptor)->b_data[offset])) =
- cpu_to_be32(record->blocknr);
- offset += 4;
+ if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT)) {
+ * ((__be64 *)(&jh2bh(descriptor)->b_data[offset])) =
+ cpu_to_be64(record->blocknr);
+ offset += 8;
+
+ } else {
+ * ((__be32 *)(&jh2bh(descriptor)->b_data[offset])) =
+ cpu_to_be32(record->blocknr);
+ offset += 4;
+ }
+
*offsetp = offset;
}
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 3251f7a..5e5aa64 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -150,14 +150,21 @@
/*
- * The block tag: used to describe a single buffer in the journal
+ * The block tag: used to describe a single buffer in the journal.
+ * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this
+ * raw struct shouldn't be used for pointer math or sizeof() - use
+ * journal_tag_bytes(journal) instead to compute this.
*/
typedef struct journal_block_tag_s
{
__be32 t_blocknr; /* The on-disk block number */
__be32 t_flags; /* See below */
+ __be32 t_blocknr_high; /* most-significant high 32bits. */
} journal_block_tag_t;
+#define JBD_TAG_SIZE32 (offsetof(journal_block_tag_t, t_blocknr_high))
+#define JBD_TAG_SIZE64 (sizeof(journal_block_tag_t))
+
/*
* The revoke descriptor: used on disk to describe a series of blocks to
* be revoked from the log
@@ -235,11 +242,13 @@
((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
#define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001
+#define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002
/* Features known to this kernel version: */
#define JBD2_KNOWN_COMPAT_FEATURES 0
#define JBD2_KNOWN_ROCOMPAT_FEATURES 0
-#define JBD2_KNOWN_INCOMPAT_FEATURES JBD2_FEATURE_INCOMPAT_REVOKE
+#define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \
+ JBD2_FEATURE_INCOMPAT_64BIT)
#ifdef __KERNEL__
@@ -1052,6 +1061,7 @@
}
extern int jbd2_journal_blocks_per_page(struct inode *inode);
+extern size_t journal_tag_bytes(journal_t *journal);
/*
* Return the minimum number of blocks which must be free in the journal