Commit 265be2d0 authored by Philipp Reisner's avatar Philipp Reisner
Browse files

drbd: Finished the "on-no-data-accessible suspend-io;" functionality 



When no data is accessible (no connection to the peer, nor a local disk)
allow the user to select to freeze all IO operations instead of getting
IO errors.

Signed-off-by: default avatarPhilipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: default avatarLars Ellenberg <lars.ellenberg@linbit.com>
parent 905cd7d8

drivers/block/drbd/drbd_int.h

+1 −0
Original line number Diff line number Diff line
@@ -1469,6 +1469,7 @@ extern int w_send_barrier(struct drbd_conf *, struct drbd_work *, int); 
extern int w_send_read_req(struct drbd_conf *, struct drbd_work *, int);

extern int w_prev_work_done(struct drbd_conf *, struct drbd_work *, int);

extern int w_e_reissue(struct drbd_conf *, struct drbd_work *, int);

extern int w_restart_disk_io(struct drbd_conf *, struct drbd_work *, int);



extern void resync_timer_fn(unsigned long data);

drivers/block/drbd/drbd_main.c

+25 −1
Original line number Diff line number Diff line
@@ -925,7 +925,12 @@ static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state 
	if (fp == FP_STONITH &&

	    (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk > D_OUTDATED) &&

	    !(os.role == R_PRIMARY && os.conn < C_CONNECTED && os.pdsk > D_OUTDATED))

		ns.susp = 1;

		ns.susp = 1; /* Suspend IO while fence-peer handler runs (peer lost) */



	if (mdev->sync_conf.on_no_data == OND_SUSPEND_IO &&

	    (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE) &&

	    !(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE))

		ns.susp = 1; /* Suspend IO while no data available (no accessible data available) */



	if (ns.aftr_isp || ns.peer_isp || ns.user_isp) {

		if (ns.conn == C_SYNC_SOURCE)
@@ -1236,6 +1241,25 @@ static void after_state_ch(struct drbd_conf *mdev, union drbd_state os, 
	/* Here we have the actions that are performed after a

	   state change. This function might sleep */



	if (os.susp && ns.susp && mdev->sync_conf.on_no_data == OND_SUSPEND_IO) {

		if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED) {

			if (ns.conn == C_CONNECTED) {

				spin_lock_irq(&mdev->req_lock);

				_tl_restart(mdev, resend);

				_drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);

				spin_unlock_irq(&mdev->req_lock);

			} else /* ns.conn > C_CONNECTED */

				dev_err(DEV, "Unexpected Resynd going on!\n");

		}



		if (os.disk == D_ATTACHING && ns.disk > D_ATTACHING) {

			spin_lock_irq(&mdev->req_lock);

			_tl_restart(mdev, restart_frozen_disk_io);

			_drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);

			spin_unlock_irq(&mdev->req_lock);

		}

	}



	if (fp == FP_STONITH && ns.susp) {

		/* case1: The outdate peer handler is successful:

		 * case2: The connection was established again: */

drivers/block/drbd/drbd_nl.c

+13 −0
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ 
#include <linux/blkpg.h>

#include <linux/cpumask.h>

#include "drbd_int.h"

#include "drbd_req.h"

#include "drbd_wrappers.h"

#include <asm/unaligned.h>

#include <linux/drbd_tag_magic.h>
@@ -494,6 +495,8 @@ char *ppsize(char *buf, unsigned long long size) 
void drbd_suspend_io(struct drbd_conf *mdev)

{

	set_bit(SUSPEND_IO, &mdev->flags);

	if (mdev->state.susp)

		return;

	wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));

}
@@ -1557,6 +1560,7 @@ static int drbd_nl_syncer_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *n 
		sc.rate       = DRBD_RATE_DEF;

		sc.after      = DRBD_AFTER_DEF;

		sc.al_extents = DRBD_AL_EXTENTS_DEF;

		sc.on_no_data  = DRBD_ON_NO_DATA_DEF;

	} else

		memcpy(&sc, &mdev->sync_conf, sizeof(struct syncer_conf));
@@ -1765,7 +1769,16 @@ static int drbd_nl_suspend_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nl 
static int drbd_nl_resume_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,

			     struct drbd_nl_cfg_reply *reply)

{

	drbd_suspend_io(mdev);

	reply->ret_code = drbd_request_state(mdev, NS(susp, 0));

	if (reply->ret_code == SS_SUCCESS) {

		if (mdev->state.conn < C_CONNECTED)

			tl_clear(mdev);

		if (mdev->state.disk == D_DISKLESS || mdev->state.disk == D_FAILED)

			tl_restart(mdev, fail_frozen_disk_io);

	}

	drbd_resume_io(mdev);



	return 0;

}

drivers/block/drbd/drbd_req.c

+24 −0
Original line number Diff line number Diff line
@@ -226,6 +226,8 @@ void _req_may_be_done(struct drbd_request *req, struct bio_and_error *m) 
		return;

	if (s & RQ_LOCAL_PENDING)

		return;

	if (mdev->state.susp)

		return;



	if (req->master_bio) {

		/* this is data_received (remote read)
@@ -634,6 +636,28 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, 
		/* else: done by handed_over_to_network */

		break;



	case fail_frozen_disk_io:

		if (!(req->rq_state & RQ_LOCAL_COMPLETED))

			break;



		_req_may_be_done(req, m);

		break;



	case restart_frozen_disk_io:

		if (!(req->rq_state & RQ_LOCAL_COMPLETED))

			break;



		req->rq_state &= ~RQ_LOCAL_COMPLETED;



		rv = MR_READ;

		if (bio_data_dir(req->master_bio) == WRITE)

			rv = MR_WRITE;



		get_ldev(mdev);

		req->w.cb = w_restart_disk_io;

		drbd_queue_work(&mdev->data.work, &req->w);

		break;



	case resend:

		/* If RQ_NET_OK is already set, we got a P_WRITE_ACK or P_RECV_ACK

		   before the connection loss; only P_BARRIER_ACK was missing.

drivers/block/drbd/drbd_req.h

+2 −0
Original line number Diff line number Diff line
@@ -105,6 +105,8 @@ enum drbd_req_event { 
	write_completed_with_error,

	completed_ok,

	resend,

	fail_frozen_disk_io,

	restart_frozen_disk_io,

	nothing, /* for tracing only */

};