On Tue, 14 Apr 2015 10:45:42 -0500 Goldwyn Rodrigues <rgoldwyn@xxxxxxx> wrote:
> When "re-add" is writted to /sys/block/mdXX/md/dev-YYY/state,
> the clustered md:
>
> 1. Sends RE_ADD message with the desc_nr. Nodes receiving the message
> clear the Faulty bit in their respective rdev->flags.
> 2. The node initiating re-add, gathers the bitmaps of all nodes
> and copies them into the local bitmap. It does not clear the bitmap
> from which it is copying.
> 3. Initiating node schedules a md recovery to sync the devices.
>
> Signed-off-by: Guoqing Jiang <gqjiang@xxxxxxxx>
> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
> ---
> drivers/md/bitmap.c | 20 +++++++++++---------
> drivers/md/bitmap.h | 2 +-
> drivers/md/md-cluster.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++-
> drivers/md/md-cluster.h | 1 +
> drivers/md/md.c | 12 ++++++++++++
> 5 files changed, 72 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
> index 5ff67c3..956cfb9 100644
> --- a/drivers/md/bitmap.c
> +++ b/drivers/md/bitmap.c
> @@ -1852,7 +1852,7 @@ EXPORT_SYMBOL_GPL(bitmap_load);
> * to our bitmap
> */
> int bitmap_copy_from_slot(struct mddev *mddev, int slot,
> - sector_t *low, sector_t *high)
> + sector_t *low, sector_t *high, bool clear_bits)
> {
> int rv = 0, i, j;
> sector_t block, lo = 0, hi = 0;
> @@ -1879,14 +1879,16 @@ int bitmap_copy_from_slot(struct mddev *mddev, int slot,
> }
> }
>
> - bitmap_update_sb(bitmap);
> - /* Setting this for the ev_page should be enough.
> - * And we do not require both write_all and PAGE_DIRT either
> - */
> - for (i = 0; i < bitmap->storage.file_pages; i++)
> - set_page_attr(bitmap, i, BITMAP_PAGE_DIRTY);
> - bitmap_write_all(bitmap);
> - bitmap_unplug(bitmap);
> + if (clear_bits) {
> + bitmap_update_sb(bitmap);
> + /* Setting this for the ev_page should be enough.
> + * And we do not require both write_all and PAGE_DIRT either
> + */
> + for (i = 0; i < bitmap->storage.file_pages; i++)
> + set_page_attr(bitmap, i, BITMAP_PAGE_DIRTY);
> + bitmap_write_all(bitmap);
> + bitmap_unplug(bitmap);
> + }
> *low = lo;
> *high = hi;
> err:
> diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h
> index 4aabc74..f1f4dd0 100644
> --- a/drivers/md/bitmap.h
> +++ b/drivers/md/bitmap.h
> @@ -263,7 +263,7 @@ void bitmap_daemon_work(struct mddev *mddev);
> int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
> int chunksize, int init);
> int bitmap_copy_from_slot(struct mddev *mddev, int slot,
> - sector_t *lo, sector_t *hi);
> + sector_t *lo, sector_t *hi, bool clear_bits);
> #endif
>
> #endif
> diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
> index 82f1b7b..ad2b5b7 100644
> --- a/drivers/md/md-cluster.c
> +++ b/drivers/md/md-cluster.c
> @@ -73,6 +73,7 @@ enum msg_type {
> RESYNCING,
> NEWDISK,
> REMOVE,
> + RE_ADD,
> };
>
> struct cluster_msg {
> @@ -253,7 +254,7 @@ void recover_bitmaps(struct md_thread *thread)
> str, ret);
> goto clear_bit;
> }
> - ret = bitmap_copy_from_slot(mddev, slot, &lo, &hi);
> + ret = bitmap_copy_from_slot(mddev, slot, &lo, &hi, true);
> if (ret) {
> pr_err("md-cluster: Could not copy data from bitmap %d\n", slot);
> goto dlm_unlock;
> @@ -412,6 +413,16 @@ static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
> pr_warn("%s: %d Could not find disk(%d) to REMOVE\n", __func__, __LINE__, msg->raid_slot);
> }
>
> +static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
> +{
> + struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev, msg->raid_slot);
> +
> + if (rdev && test_bit(Faulty, &rdev->flags))
> + clear_bit(Faulty, &rdev->flags);
> + else
> + pr_warn("%s: %d Could not find disk(%d) which is faulty", __func__, __LINE__, msg->raid_slot);
> +}
> +
> static void process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
> {
> switch (msg->type) {
> @@ -436,6 +447,11 @@ static void process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
> __func__, __LINE__, msg->slot);
> process_remove_disk(mddev, msg);
> break;
> + case RE_ADD:
> + pr_info("%s: %d Received RE_ADD from %d\n",
> + __func__, __LINE__, msg->slot);
> + process_readd_disk(mddev, msg);
> + break;
> default:
> pr_warn("%s:%d Received unknown message from %d\n",
> __func__, __LINE__, msg->slot);
> @@ -883,6 +899,35 @@ static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
> return __sendmsg(cinfo, &cmsg);
> }
>
> +static int gather_bitmaps(struct md_rdev *rdev)
> +{
> + int sn, err;
> + sector_t lo, hi;
> + struct cluster_msg cmsg;
> + struct mddev *mddev = rdev->mddev;
> + struct md_cluster_info *cinfo = mddev->cluster_info;
> +
> + cmsg.type = RE_ADD;
> + cmsg.raid_slot = rdev->desc_nr;
> + err = sendmsg(cinfo, &cmsg);
> + if (err)
> + goto out;
> +
> + for (sn = 0; sn < mddev->bitmap_info.nodes; sn++) {
> + if (sn == (cinfo->slot_number - 1))
> + continue;
> + err = bitmap_copy_from_slot(mddev, sn, &lo, &hi, false);
> + if (err) {
> + pr_warn("md-cluster: Could not gather bitmaps from slot %d", sn);
> + goto out;
> + }
> + if ((hi > 0) && (lo < mddev->recovery_cp))
> + mddev->recovery_cp = lo;
> + }
> +out:
> + return err;
> +}
> +
> static struct md_cluster_operations cluster_ops = {
> .join = join,
> .leave = leave,
> @@ -898,6 +943,7 @@ static struct md_cluster_operations cluster_ops = {
> .add_new_disk_finish = add_new_disk_finish,
> .new_disk_ack = new_disk_ack,
> .remove_disk = remove_disk,
> + .gather_bitmaps = gather_bitmaps,
> };
>
> static int __init cluster_init(void)
> diff --git a/drivers/md/md-cluster.h b/drivers/md/md-cluster.h
> index 71e5143..6817ee0 100644
> --- a/drivers/md/md-cluster.h
> +++ b/drivers/md/md-cluster.h
> @@ -23,6 +23,7 @@ struct md_cluster_operations {
> int (*add_new_disk_finish)(struct mddev *mddev);
> int (*new_disk_ack)(struct mddev *mddev, bool ack);
> int (*remove_disk)(struct mddev *mddev, struct md_rdev *rdev);
> + int (*gather_bitmaps)(struct md_rdev *rdev);
> };
>
> #endif /* _MD_CLUSTER_H */
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index ba01605..8c37bbf 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -2599,11 +2599,23 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
> err = 0;
> }
> } else if (cmd_match(buf, "re-add") && (test_bit(Faulty, &rdev->flags) || (rdev->raid_disk == -1))) {
> + /* clear_bit is performed _after_ all the devices
> + * have their local Faulty bit cleared. If any writes
> + * happen in the meantime in the local node, they
> + * will land in the local bitmap, which will be synced
> + * by this node eventually
> + */
> + if (mddev_is_clustered(rdev->mddev)) {
> + err = md_cluster_ops->gather_bitmaps(rdev);
> + if (err)
> + goto out;
> + }
> clear_bit(Faulty, &rdev->flags);
> err = add_bound_rdev(rdev);
> }
> if (!err)
> sysfs_notify_dirent_safe(rdev->sysfs_state);
> +out:
> return err ? err : len;
> }
> static struct rdev_sysfs_entry rdev_state =
I changed this to:
if (!mddev_is_clustered(rdev->mddev) ||
(err = md_cluster_ops->gather_bitmaps(rdev)) == 0) {
clear_bit(Faulty, &rdev->flags);
err = add_bound_rdev(rdev);
}
because I think it makes the code a bit clearer.
otherwise, applied.
Thanks,
NeilBrown
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