[PATCH] md: all hot-add and hot-remove of md intent logging bitmaps
Both file-bitmaps and superblock bitmaps are supported.
If you add a bitmap file on the array device, you lose.
This introduces a 'default_bitmap_offset' field in mddev, as the ioctl used
for adding a superblock bitmap doesn't have room for giving an offset. Later,
this value will be setable via sysfs.
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 63c5661..ae65446 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -623,6 +623,7 @@
mddev->size = sb->size;
mddev->events = md_event(sb);
mddev->bitmap_offset = 0;
+ mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
if (sb->state & (1<<MD_SB_CLEAN))
mddev->recovery_cp = MaxSector;
@@ -648,7 +649,7 @@
printk(KERN_WARNING "md: bitmaps only support for raid1\n");
return -EINVAL;
}
- mddev->bitmap_offset = (MD_SB_BYTES >> 9);
+ mddev->bitmap_offset = mddev->default_bitmap_offset;
}
} else if (mddev->pers == NULL) {
@@ -939,6 +940,9 @@
mddev->size = le64_to_cpu(sb->size)/2;
mddev->events = le64_to_cpu(sb->events);
mddev->bitmap_offset = 0;
+ mddev->default_bitmap_offset = 0;
+ if (mddev->minor_version == 0)
+ mddev->default_bitmap_offset = -(64*1024)/512;
mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
memcpy(mddev->uuid, sb->set_uuid, 16);
@@ -2073,6 +2077,8 @@
info.state = 0;
if (mddev->in_sync)
info.state = (1<<MD_SB_CLEAN);
+ if (mddev->bitmap && mddev->bitmap_offset)
+ info.state = (1<<MD_SB_BITMAP_PRESENT);
info.active_disks = active;
info.working_disks = working;
info.failed_disks = failed;
@@ -2430,25 +2436,51 @@
{
int err;
- if (mddev->pers || mddev->bitmap_file)
- return -EBUSY;
-
- mddev->bitmap_file = fget(fd);
-
- if (mddev->bitmap_file == NULL) {
- printk(KERN_ERR "%s: error: failed to get bitmap file\n",
- mdname(mddev));
- return -EBADF;
+ if (mddev->pers) {
+ if (!mddev->pers->quiesce)
+ return -EBUSY;
+ if (mddev->recovery || mddev->sync_thread)
+ return -EBUSY;
+ /* we should be able to change the bitmap.. */
}
- err = deny_bitmap_write_access(mddev->bitmap_file);
- if (err) {
- printk(KERN_ERR "%s: error: bitmap file is already in use\n",
- mdname(mddev));
- fput(mddev->bitmap_file);
- mddev->bitmap_file = NULL;
- } else
+
+ if (fd >= 0) {
+ if (mddev->bitmap)
+ return -EEXIST; /* cannot add when bitmap is present */
+ mddev->bitmap_file = fget(fd);
+
+ if (mddev->bitmap_file == NULL) {
+ printk(KERN_ERR "%s: error: failed to get bitmap file\n",
+ mdname(mddev));
+ return -EBADF;
+ }
+
+ err = deny_bitmap_write_access(mddev->bitmap_file);
+ if (err) {
+ printk(KERN_ERR "%s: error: bitmap file is already in use\n",
+ mdname(mddev));
+ fput(mddev->bitmap_file);
+ mddev->bitmap_file = NULL;
+ return err;
+ }
mddev->bitmap_offset = 0; /* file overrides offset */
+ } else if (mddev->bitmap == NULL)
+ return -ENOENT; /* cannot remove what isn't there */
+ err = 0;
+ if (mddev->pers) {
+ mddev->pers->quiesce(mddev, 1);
+ if (fd >= 0)
+ err = bitmap_create(mddev);
+ if (fd < 0 || err)
+ bitmap_destroy(mddev);
+ mddev->pers->quiesce(mddev, 0);
+ } else if (fd < 0) {
+ if (mddev->bitmap_file)
+ fput(mddev->bitmap_file);
+ mddev->bitmap_file = NULL;
+ }
+
return err;
}
@@ -2528,6 +2560,11 @@
{
int rv = 0;
int cnt = 0;
+ int state = 0;
+
+ /* calculate expected state,ignoring low bits */
+ if (mddev->bitmap && mddev->bitmap_offset)
+ state |= (1 << MD_SB_BITMAP_PRESENT);
if (mddev->major_version != info->major_version ||
mddev->minor_version != info->minor_version ||
@@ -2536,12 +2573,16 @@
mddev->level != info->level ||
/* mddev->layout != info->layout || */
!mddev->persistent != info->not_persistent||
- mddev->chunk_size != info->chunk_size )
+ mddev->chunk_size != info->chunk_size ||
+ /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
+ ((state^info->state) & 0xfffffe00)
+ )
return -EINVAL;
/* Check there is only one change */
if (mddev->size != info->size) cnt++;
if (mddev->raid_disks != info->raid_disks) cnt++;
if (mddev->layout != info->layout) cnt++;
+ if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) cnt++;
if (cnt == 0) return 0;
if (cnt > 1) return -EINVAL;
@@ -2620,6 +2661,35 @@
}
}
}
+ if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
+ if (mddev->pers->quiesce == NULL)
+ return -EINVAL;
+ if (mddev->recovery || mddev->sync_thread)
+ return -EBUSY;
+ if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
+ /* add the bitmap */
+ if (mddev->bitmap)
+ return -EEXIST;
+ if (mddev->default_bitmap_offset == 0)
+ return -EINVAL;
+ mddev->bitmap_offset = mddev->default_bitmap_offset;
+ mddev->pers->quiesce(mddev, 1);
+ rv = bitmap_create(mddev);
+ if (rv)
+ bitmap_destroy(mddev);
+ mddev->pers->quiesce(mddev, 0);
+ } else {
+ /* remove the bitmap */
+ if (!mddev->bitmap)
+ return -ENOENT;
+ if (mddev->bitmap->file)
+ return -EINVAL;
+ mddev->pers->quiesce(mddev, 1);
+ bitmap_destroy(mddev);
+ mddev->pers->quiesce(mddev, 0);
+ mddev->bitmap_offset = 0;
+ }
+ }
md_update_sb(mddev);
return rv;
}
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index ace41c5..ba643e4 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1565,6 +1565,35 @@
return 0;
}
+void raid1_quiesce(mddev_t *mddev, int state)
+{
+ conf_t *conf = mddev_to_conf(mddev);
+
+ switch(state) {
+ case 0:
+ spin_lock_irq(&conf->resync_lock);
+ conf->barrier++;
+ wait_event_lock_irq(conf->wait_idle, !conf->nr_pending,
+ conf->resync_lock, raid1_unplug(mddev->queue));
+ spin_unlock_irq(&conf->resync_lock);
+ break;
+ case 1:
+ spin_lock_irq(&conf->resync_lock);
+ conf->barrier--;
+ spin_unlock_irq(&conf->resync_lock);
+ wake_up(&conf->wait_resume);
+ wake_up(&conf->wait_idle);
+ break;
+ }
+ if (mddev->thread) {
+ if (mddev->bitmap)
+ mddev->thread->timeout = mddev->bitmap->daemon_sleep * HZ;
+ else
+ mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
+ md_wakeup_thread(mddev->thread);
+ }
+}
+
static mdk_personality_t raid1_personality =
{
@@ -1581,6 +1610,7 @@
.sync_request = sync_request,
.resize = raid1_resize,
.reshape = raid1_reshape,
+ .quiesce = raid1_quiesce,
};
static int __init raid_init(void)
diff --git a/include/linux/raid/md_k.h b/include/linux/raid/md_k.h
index 8c14ba5..817062b 100644
--- a/include/linux/raid/md_k.h
+++ b/include/linux/raid/md_k.h
@@ -278,6 +278,10 @@
* start of bitmap. May be
* negative, but not '0'
*/
+ long default_bitmap_offset; /* this is the offset to use when
+ * hot-adding a bitmap. It should
+ * eventually be settable by sysfs.
+ */
struct list_head all_mddevs;
};
@@ -314,6 +318,12 @@
int (*resize) (mddev_t *mddev, sector_t sectors);
int (*reshape) (mddev_t *mddev, int raid_disks);
int (*reconfig) (mddev_t *mddev, int layout, int chunk_size);
+ /* quiesce moves between quiescence states
+ * 0 - fully active
+ * 1 - no new requests allowed
+ * others - reserved
+ */
+ void (*quiesce) (mddev_t *mddev, int state);
};
