From: Alasdair G Kergon <agk@redhat.com>
From: Heinz Mauelshagen <mauelshagen@redhat.com>
Make mirror log synchronization optional.
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/md/dm-log.c | 110 ++++++++++++++++++++++++++++++++++++------
25-akpm/drivers/md/dm-log.h | 6 ++
25-akpm/drivers/md/dm-raid1.c | 14 ++---
3 files changed, 108 insertions(+), 22 deletions(-)
diff -puN drivers/md/dm-log.c~device-mapper-mirror-log-sync-optional drivers/md/dm-log.c
--- 25/drivers/md/dm-log.c~device-mapper-mirror-log-sync-optional Tue Sep 21 14:23:17 2004
+++ 25-akpm/drivers/md/dm-log.c Tue Sep 21 14:23:17 2004
@@ -140,6 +140,13 @@ struct log_c {
int sync_search;
+ /* Resync flag */
+ enum sync {
+ DEFAULTSYNC, /* Synchronize if necessary */
+ NOSYNC, /* Devices known to be already in sync */
+ FORCESYNC, /* Force a sync to happen */
+ } sync;
+
/*
* Disk log fields
*/
@@ -205,7 +212,8 @@ static int read_header(struct log_c *log
header_from_disk(&log->header, log->disk_header);
- if (log->header.magic != MIRROR_MAGIC) {
+ /* New log required? */
+ if (log->sync != DEFAULTSYNC || log->header.magic != MIRROR_MAGIC) {
log->header.magic = MIRROR_MAGIC;
log->header.version = MIRROR_DISK_VERSION;
log->header.nr_regions = 0;
@@ -273,22 +281,38 @@ static int write_bits(struct log_c *log)
}
/*----------------------------------------------------------------
- * constructor/destructor
+ * core log constructor/destructor
+ *
+ * argv contains region_size followed optionally by [no]sync
*--------------------------------------------------------------*/
#define BYTE_SHIFT 3
static int core_ctr(struct dirty_log *log, struct dm_target *ti,
unsigned int argc, char **argv)
{
+ enum sync sync = DEFAULTSYNC;
+
struct log_c *lc;
sector_t region_size;
unsigned int region_count;
size_t bitset_size;
- if (argc != 1) {
- DMWARN("wrong number of arguments to log_c");
+ if (argc < 1 || argc > 2) {
+ DMWARN("wrong number of arguments to mirror log");
return -EINVAL;
}
+ if (argc > 1) {
+ if (!strcmp(argv[1], "sync"))
+ sync = FORCESYNC;
+ else if (!strcmp(argv[1], "nosync"))
+ sync = NOSYNC;
+ else {
+ DMWARN("unrecognised sync argument to mirror log: %s",
+ argv[1]);
+ return -EINVAL;
+ }
+ }
+
if (sscanf(argv[0], SECTOR_FORMAT, ®ion_size) != 1) {
DMWARN("invalid region size string");
return -EINVAL;
@@ -306,6 +330,7 @@ static int core_ctr(struct dirty_log *lo
lc->touched = 0;
lc->region_size = region_size;
lc->region_count = region_count;
+ lc->sync = sync;
/*
* Work out how many words we need to hold the bitset.
@@ -330,8 +355,8 @@ static int core_ctr(struct dirty_log *lo
kfree(lc);
return -ENOMEM;
}
- memset(lc->sync_bits, 0, bitset_size);
- lc->sync_count = 0;
+ memset(lc->sync_bits, (sync == NOSYNC) ? -1 : 0, bitset_size);
+ lc->sync_count = (sync == NOSYNC) ? region_count : 0;
lc->recovering_bits = vmalloc(bitset_size);
if (!lc->recovering_bits) {
@@ -356,6 +381,11 @@ static void core_dtr(struct dirty_log *l
kfree(lc);
}
+/*----------------------------------------------------------------
+ * disk log constructor/destructor
+ *
+ * argv contains log_device region_size followed optionally by [no]sync
+ *--------------------------------------------------------------*/
static int disk_ctr(struct dirty_log *log, struct dm_target *ti,
unsigned int argc, char **argv)
{
@@ -364,8 +394,8 @@ static int disk_ctr(struct dirty_log *lo
struct log_c *lc;
struct dm_dev *dev;
- if (argc != 2) {
- DMWARN("wrong number of arguments to log_d");
+ if (argc < 2 || argc > 3) {
+ DMWARN("wrong number of arguments to disk mirror log");
return -EINVAL;
}
@@ -452,10 +482,15 @@ static int disk_resume(struct dirty_log
if (r)
return r;
- /* zero any new bits if the mirror has grown */
- for (i = lc->header.nr_regions; i < lc->region_count; i++)
- /* FIXME: amazingly inefficient */
- log_clear_bit(lc, lc->clean_bits, i);
+ /* set or clear any new bits */
+ if (lc->sync == NOSYNC)
+ for (i = lc->header.nr_regions; i < lc->region_count; i++)
+ /* FIXME: amazingly inefficient */
+ log_set_bit(lc, lc->clean_bits, i);
+ else
+ for (i = lc->header.nr_regions; i < lc->region_count; i++)
+ /* FIXME: amazingly inefficient */
+ log_clear_bit(lc, lc->clean_bits, i);
/* copy clean across to sync */
memcpy(lc->sync_bits, lc->clean_bits, size);
@@ -566,6 +601,51 @@ static region_t core_get_sync_count(stru
return lc->sync_count;
}
+#define DMEMIT_SYNC \
+ if (lc->sync != DEFAULTSYNC) \
+ DMEMIT("%ssync ", lc->sync == NOSYNC ? "no" : "")
+
+static int core_status(struct dirty_log *log, status_type_t status,
+ char *result, unsigned int maxlen)
+{
+ int sz = 0;
+ struct log_c *lc = log->context;
+
+ switch(status) {
+ case STATUSTYPE_INFO:
+ break;
+
+ case STATUSTYPE_TABLE:
+ DMEMIT("%s %u " SECTOR_FORMAT " ", log->type->name,
+ lc->sync == DEFAULTSYNC ? 1 : 2, lc->region_size);
+ DMEMIT_SYNC;
+ }
+
+ return sz;
+}
+
+static int disk_status(struct dirty_log *log, status_type_t status,
+ char *result, unsigned int maxlen)
+{
+ int sz = 0;
+ char buffer[16];
+ struct log_c *lc = log->context;
+
+ switch(status) {
+ case STATUSTYPE_INFO:
+ break;
+
+ case STATUSTYPE_TABLE:
+ format_dev_t(buffer, lc->log_dev->bdev->bd_dev);
+ DMEMIT("%s %u %s " SECTOR_FORMAT " ", log->type->name,
+ lc->sync == DEFAULTSYNC ? 2 : 3, buffer,
+ lc->region_size);
+ DMEMIT_SYNC;
+ }
+
+ return sz;
+}
+
static struct dirty_log_type _core_type = {
.name = "core",
.module = THIS_MODULE,
@@ -579,7 +659,8 @@ static struct dirty_log_type _core_type
.clear_region = core_clear_region,
.get_resync_work = core_get_resync_work,
.complete_resync_work = core_complete_resync_work,
- .get_sync_count = core_get_sync_count
+ .get_sync_count = core_get_sync_count,
+ .status = core_status,
};
static struct dirty_log_type _disk_type = {
@@ -597,7 +678,8 @@ static struct dirty_log_type _disk_type
.clear_region = core_clear_region,
.get_resync_work = core_get_resync_work,
.complete_resync_work = core_complete_resync_work,
- .get_sync_count = core_get_sync_count
+ .get_sync_count = core_get_sync_count,
+ .status = disk_status,
};
int __init dm_dirty_log_init(void)
diff -puN drivers/md/dm-log.h~device-mapper-mirror-log-sync-optional drivers/md/dm-log.h
--- 25/drivers/md/dm-log.h~device-mapper-mirror-log-sync-optional Tue Sep 21 14:23:17 2004
+++ 25-akpm/drivers/md/dm-log.h Tue Sep 21 14:23:17 2004
@@ -101,6 +101,12 @@ struct dirty_log_type {
* Returns the number of regions that are in sync.
*/
region_t (*get_sync_count)(struct dirty_log *log);
+
+ /*
+ * Support function for mirror status requests.
+ */
+ int (*status)(struct dirty_log *log, status_type_t status_type,
+ char *result, unsigned int maxlen);
};
int dm_register_dirty_log_type(struct dirty_log_type *type);
diff -puN drivers/md/dm-raid1.c~device-mapper-mirror-log-sync-optional drivers/md/dm-raid1.c
--- 25/drivers/md/dm-raid1.c~device-mapper-mirror-log-sync-optional Tue Sep 21 14:23:17 2004
+++ 25-akpm/drivers/md/dm-raid1.c Tue Sep 21 14:23:17 2004
@@ -1009,8 +1009,8 @@ static struct dirty_log *create_dirty_lo
* log_type #log_params <log_params>
* #mirrors [mirror_path offset]{2,}
*
- * For now, #log_params = 1, log_type = "core"
- *
+ * log_type is "core" or "disk"
+ * #log_params is between 1 and 3
*/
#define DM_IO_PAGES 64
static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
@@ -1182,13 +1182,14 @@ static int mirror_status(struct dm_targe
char *result, unsigned int maxlen)
{
char buffer[32];
- unsigned int m, sz = 0;
+ unsigned int m, sz;
struct mirror_set *ms = (struct mirror_set *) ti->private;
+ sz = ms->rh.log->type->status(ms->rh.log, type, result, maxlen);
+
switch (type) {
case STATUSTYPE_INFO:
DMEMIT("%d ", ms->nr_mirrors);
-
for (m = 0; m < ms->nr_mirrors; m++) {
format_dev_t(buffer, ms->mirror[m].dev->bdev->bd_dev);
DMEMIT("%s ", buffer);
@@ -1200,10 +1201,7 @@ static int mirror_status(struct dm_targe
break;
case STATUSTYPE_TABLE:
- DMEMIT("%s 1 " SECTOR_FORMAT " %d ",
- ms->rh.log->type->name, ms->rh.region_size,
- ms->nr_mirrors);
-
+ DMEMIT("%d ", ms->nr_mirrors);
for (m = 0; m < ms->nr_mirrors; m++) {
format_dev_t(buffer, ms->mirror[m].dev->bdev->bd_dev);
DMEMIT("%s " SECTOR_FORMAT " ",
_