vserver 1.9.3

[linux-2.6.git] / drivers / md / dm-log.c

diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c
index 7a1c77d..43a1228 100644 (file)
--- a/drivers/md/dm-log.c
+++ b/drivers/md/dm-log.c
@@ -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, &region_size) != 1) {
                DMWARN("invalid region size string");
                return -EINVAL;
@@ -306,6 +330,7 @@ static int core_ctr(struct dirty_log *log, struct dm_target *ti,
        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 *log, struct dm_target *ti,
                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 *log)
        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 *log, struct dm_target *ti,
        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 *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(struct dirty_log *log)
         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)