> You assume here that near_copies is 2, but you never check for that.
>
Fixed.
> Also - and this applies to raid5 and raid10 - the devices may not be
> all the
> same size. raid5 and raid10 will just use the size of the smallest
> device,
> but raid0 won't. For for a seamless conversion, you need to handle the
> case
> that the devices are not the same size. Either disallow that case, or
> make
> use of the extra space.
>
I've removed setup_conf() from the original patch.
Now raid0 reuses create_strip_zones() when takeovering from Raid5 and from Raid10,
so multiply zones are supported.
Is it the right solution for the second problem?
Thanks,
Maciek Trela.
Signed-off-by: Maciej Trela <maciej.trela@xxxxxxxxx>
---
drivers/md/raid0.c | 116 +++++++++++++++++++++++++++++++++++++++++++++++++--
1 files changed, 111 insertions(+), 5 deletions(-)
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index 77605cd..35d1869 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -22,6 +22,7 @@
#include <linux/seq_file.h>
#include "md.h"
#include "raid0.h"
+#include "raid5.h"
static void raid0_unplug(struct request_queue *q)
{
@@ -87,7 +88,7 @@ static void dump_zones(mddev_t *mddev)
printk(KERN_INFO "**********************************\n\n");
}
-static int create_strip_zones(mddev_t *mddev)
+static int create_strip_zones(mddev_t *mddev, void** private_conf)
{
int i, c, err;
sector_t curr_zone_end, sectors;
@@ -260,7 +261,9 @@ static int create_strip_zones(mddev_t *mddev)
(mddev->chunk_sectors << 9) * mddev->raid_disks);
printk(KERN_INFO "raid0: done.\n");
- mddev->private = conf;
+ if (private_conf)
+ *private_conf = conf;
+
return 0;
abort:
kfree(conf->strip_zone);
@@ -328,9 +331,13 @@ static int raid0_run(mddev_t *mddev)
blk_queue_max_sectors(mddev->queue, mddev->chunk_sectors);
mddev->queue->queue_lock = &mddev->queue->__queue_lock;
- ret = create_strip_zones(mddev);
- if (ret < 0)
- return ret;
+ /* if private is not null, we are here after takeover */
+ if (mddev->private == NULL)
+ {
+ ret = create_strip_zones(mddev, &mddev->private);
+ if (ret < 0)
+ return ret;
+ }
/* calculate array device size */
md_set_array_sectors(mddev, raid0_size(mddev, 0, 0));
@@ -542,6 +549,103 @@ static void raid0_status(struct seq_file *seq, mddev_t *mddev)
return;
}
+static void *raid0_takeover_raid5(mddev_t *mddev)
+{
+ mdk_rdev_t *rdev;
+ raid0_conf_t *priv_conf;
+
+ if (mddev->degraded != 1) {
+ printk("error: raid5 must be degraded! Degraded disks: %d\n",
+ mddev->degraded);
+ return ERR_PTR(-EINVAL);
+ }
+
+ list_for_each_entry(rdev, &mddev->disks, same_set) {
+ /* check slot number for a disk */
+ if (rdev->raid_disk == mddev->raid_disks-1) {
+ printk("error: raid5 must have missing parity disk!\n");
+ return ERR_PTR(-EINVAL);
+ }
+ }
+
+ /* Set new parameters */
+ mddev->new_level = 0;
+ mddev->new_chunk_sectors = mddev->chunk_sectors;
+ mddev->degraded = 0;
+ mddev->raid_disks--;
+ mddev->delta_disks = -1;
+ /* make sure it will be not marked as dirty */
+ mddev->recovery_cp = MaxSector;
+
+ create_strip_zones(mddev, (void**)&priv_conf);
+ return priv_conf;
+}
+
+static void *raid0_takeover_raid10(mddev_t *mddev)
+{
+ mdk_rdev_t *rdev;
+ raid0_conf_t *priv_conf;
+
+ /* Check layout:
+ * - far_copies must be 1
+ * - near_copies must be 2
+ * - disks number must be even
+ * - all mirrors must be already degraded
+ */
+ if (mddev->layout != ((1 << 8) + 2)) {
+ printk(KERN_ERR "error: Raid0 cannot takover layout: %x\n", mddev->layout);
+ return ERR_PTR(-EINVAL);
+ }
+ if (mddev->raid_disks & 1) {
+ printk(KERN_ERR "error: Raid0 cannot takover Raid10 with odd disk number.\n");
+ return ERR_PTR(-EINVAL);
+ }
+ if (mddev->degraded != (mddev->raid_disks>>1)) {
+ printk(KERN_ERR "error: All mirrors must be already degraded!\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ /* Set new parameters */
+ mddev->new_level = 0;
+ mddev->new_chunk_sectors = mddev->chunk_sectors;
+ mddev->raid_disks -= mddev->degraded;
+ mddev->delta_disks = -mddev->degraded;
+ mddev->degraded = 0;
+ /* make sure it will be not marked as dirty */
+ mddev->recovery_cp = MaxSector;
+
+ list_for_each_entry(rdev, &mddev->disks, same_set) {
+ rdev->raid_disk /= 2;
+ }
+
+ create_strip_zones(mddev, (void**)&priv_conf);
+ return priv_conf;
+}
+
+static void *raid0_takeover(mddev_t *mddev)
+{
+ /* raid0 can take over:
+ * raid5 - providing it is Raid4 layout and one disk is faulty
+ * raid10 - assuming we have all necessary active disks
+ */
+ if (mddev->level == 5) {
+ if (mddev->layout == ALGORITHM_PARITY_N) {
+ return raid0_takeover_raid5(mddev);
+ }
+ printk("Error: Raid can only takeover Raid5 with layout: %d\n",
+ ALGORITHM_PARITY_N);
+ }
+
+ if (mddev->level == 10)
+ return raid0_takeover_raid10(mddev);
+
+ return ERR_PTR(-EINVAL);
+}
+
+static void raid0_quiesce(mddev_t *mddev, int state)
+{
+}
+
static struct mdk_personality raid0_personality=
{
.name = "raid0",
@@ -552,6 +656,8 @@ static struct mdk_personality raid0_personality=
.stop = raid0_stop,
.status = raid0_status,
.size = raid0_size,
+ .takeover = raid0_takeover,
+ .quiesce = raid0_quiesce,
};
static int __init raid0_init (void)
--
1.6.3.3
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
