On Tue, Feb 21, 2017 at 08:44:00PM +0100, Artur Paszkiewicz wrote:
> Add a function to modify the log by removing an rdev when a drive fails
> or adding when a spare/replacement is activated as a raid member.
>
> Removing a disk just clears the child log rdev pointer. No new stripes
> will be accepted for this child log in ppl_write_stripe() and running io
> units will be processed without writing PPL to the device.
>
> Adding a disk sets the child log rdev pointer and writes an empty PPL
> header.
>
> Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@xxxxxxxxx>
> ---
> drivers/md/raid5-ppl.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> drivers/md/raid5.c | 15 +++++++++++++++
> drivers/md/raid5.h | 8 ++++++++
> 3 files changed, 70 insertions(+)
>
> diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c
> index a7693353243a..c2070d124849 100644
> --- a/drivers/md/raid5-ppl.c
> +++ b/drivers/md/raid5-ppl.c
> @@ -319,6 +319,12 @@ static void ppl_submit_iounit(struct ppl_io_unit *io)
>
> bio = bio_alloc_bioset(GFP_NOIO, BIO_MAX_PAGES, ppl_conf->bs);
> bio->bi_private = io;
> +
> + if (!log->rdev || test_bit(Faulty, &log->rdev->flags)) {
> + ppl_log_endio(bio);
> + return;
> + }
> +
> bio->bi_end_io = ppl_log_endio;
> bio->bi_opf = REQ_OP_WRITE | REQ_FUA;
> bio->bi_bdev = log->rdev->bdev;
> @@ -1098,3 +1104,44 @@ int ppl_init_log(struct r5conf *conf)
> ppl_exit_log(ppl_conf);
> return ret;
> }
> +
> +int ppl_modify_log(struct ppl_conf *ppl_conf, struct md_rdev *rdev,
> + enum ppl_modify_log_operation operation)
> +{
> + struct ppl_log *log;
> + int ret = 0;
> + char b[BDEVNAME_SIZE];
> +
> + if (!rdev)
> + return -EINVAL;
> +
> + pr_debug("%s: disk: %d operation: %s dev: %s\n",
> + __func__, rdev->raid_disk,
> + operation == PPL_MODIFY_LOG_DISK_REMOVE ? "remove" :
> + (operation == PPL_MODIFY_LOG_DISK_ADD ? "add" : "?"),
> + bdevname(rdev->bdev, b));
> +
> + if (rdev->raid_disk < 0)
> + return 0;
> +
> + if (rdev->raid_disk >= ppl_conf->count)
> + return -ENODEV;
> +
> + log = &ppl_conf->child_logs[rdev->raid_disk];
> +
> + mutex_lock(&log->io_mutex);
> + if (operation == PPL_MODIFY_LOG_DISK_REMOVE) {
> + log->rdev = NULL;
> + } else if (operation == PPL_MODIFY_LOG_DISK_ADD) {
> + ret = ppl_validate_rdev(rdev);
> + if (!ret) {
> + log->rdev = rdev;
> + ret = ppl_write_empty_header(log);
> + }
> + } else {
> + ret = -EINVAL;
> + }
> + mutex_unlock(&log->io_mutex);
> +
> + return ret;
> +}
> diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
> index 8b52392457d8..b17e90f06f19 100644
> --- a/drivers/md/raid5.c
> +++ b/drivers/md/raid5.c
> @@ -7623,6 +7623,12 @@ static int raid5_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
> *rdevp = rdev;
> }
> }
> + if (conf->ppl) {
> + err = ppl_modify_log(conf->ppl, rdev,
> + PPL_MODIFY_LOG_DISK_REMOVE);
> + if (err)
> + goto abort;
> + }
> if (p->replacement) {
> /* We must have just cleared 'rdev' */
> p->rdev = p->replacement;
> @@ -7632,6 +7638,10 @@ static int raid5_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
> */
> p->replacement = NULL;
> clear_bit(WantReplacement, &rdev->flags);
> +
> + if (conf->ppl)
> + err = ppl_modify_log(conf->ppl, p->rdev,
> + PPL_MODIFY_LOG_DISK_ADD);
> } else
> /* We might have just removed the Replacement as faulty-
> * clear the bit just in case
> @@ -7695,6 +7705,11 @@ static int raid5_add_disk(struct mddev *mddev, struct md_rdev *rdev)
> if (rdev->saved_raid_disk != disk)
> conf->fullsync = 1;
> rcu_assign_pointer(p->rdev, rdev);
> +
> + if (conf->ppl)
> + err = ppl_modify_log(conf->ppl, rdev,
> + PPL_MODIFY_LOG_DISK_ADD);
> +
> goto out;
> }
> }
> diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
> index f915a7a0e752..43cfa5fa71b3 100644
> --- a/drivers/md/raid5.h
> +++ b/drivers/md/raid5.h
> @@ -806,4 +806,12 @@ extern void ppl_exit_log(struct ppl_conf *log);
> extern int ppl_write_stripe(struct ppl_conf *log, struct stripe_head *sh);
> extern void ppl_write_stripe_run(struct ppl_conf *log);
> extern void ppl_stripe_write_finished(struct stripe_head *sh);
> +
> +enum ppl_modify_log_operation {
> + PPL_MODIFY_LOG_DISK_REMOVE,
> + PPL_MODIFY_LOG_DISK_ADD,
> +};
a bool for this parameter is better
> +extern int ppl_modify_log(struct ppl_conf *log, struct md_rdev *rdev,
> + enum ppl_modify_log_operation operation);
So this should be put into raid5-log.h and rename to log_modify_log(conf, xxx)
or other sensible name.
Thanks,
Shaohua
--
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
