Commit 85f75dd7 authored by Lars Ellenberg's avatar Lars Ellenberg Committed by Philipp Reisner
Browse files

drbd: introduce in-kernel "down" command 



This greatly simplifies deconfiguration of whole resources.

Signed-off-by: default avatarPhilipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: default avatarLars Ellenberg <lars.ellenberg@linbit.com>
parent 3c5e5f6a

drivers/block/drbd/drbd_main.c

+0 −2
Original line number Diff line number Diff line
@@ -2303,9 +2303,7 @@ struct drbd_tconn *drbd_new_tconn(const char *name) 


void drbd_free_tconn(struct drbd_tconn *tconn)

{

	mutex_lock(&drbd_cfg_mutex);

	list_del(&tconn->all_tconn);

	mutex_unlock(&drbd_cfg_mutex);

	idr_destroy(&tconn->volumes);



	free_cpumask_var(tconn->cpu_mask);

drivers/block/drbd/drbd_nl.c

+152 −51
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ int drbd_adm_delete_minor(struct sk_buff *skb, struct genl_info *info); 


int drbd_adm_create_connection(struct sk_buff *skb, struct genl_info *info);

int drbd_adm_delete_connection(struct sk_buff *skb, struct genl_info *info);

int drbd_adm_down(struct sk_buff *skb, struct genl_info *info);



int drbd_adm_set_role(struct sk_buff *skb, struct genl_info *info);

int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info);
@@ -1416,6 +1417,18 @@ int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info) 
	return 0;

}



static int adm_detach(struct drbd_conf *mdev)

{

	enum drbd_ret_code retcode;

	drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */

	retcode = drbd_request_state(mdev, NS(disk, D_DISKLESS));

	wait_event(mdev->misc_wait,

			mdev->state.disk != D_DISKLESS ||

			!atomic_read(&mdev->local_cnt));

	drbd_resume_io(mdev);

	return retcode;

}



/* Detaching the disk is a process in multiple stages.  First we need to lock

 * out application IO, in-flight IO, IO stuck in drbd_al_begin_io.

 * Then we transition to D_DISKLESS, and wait for put_ldev() to return all
@@ -1423,7 +1436,6 @@ int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info) 
 * Only then we have finally detached. */

int drbd_adm_detach(struct sk_buff *skb, struct genl_info *info)

{

	struct drbd_conf *mdev;

	enum drbd_ret_code retcode;



	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
@@ -1432,13 +1444,7 @@ int drbd_adm_detach(struct sk_buff *skb, struct genl_info *info) 
	if (retcode != NO_ERROR)

		goto out;



	mdev = adm_ctx.mdev;

	drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */

	retcode = drbd_request_state(mdev, NS(disk, D_DISKLESS));

	wait_event(mdev->misc_wait,

			mdev->state.disk != D_DISKLESS ||

			!atomic_read(&mdev->local_cnt));

	drbd_resume_io(mdev);

	retcode = adm_detach(adm_ctx.mdev);

out:

	drbd_adm_finish(info, retcode);

	return 0;
@@ -1680,10 +1686,49 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info) 
	return 0;

}



static enum drbd_state_rv conn_try_disconnect(struct drbd_tconn *tconn, bool force)

{

	enum drbd_state_rv rv;

	if (force) {

		spin_lock_irq(&tconn->req_lock);

		if (tconn->cstate >= C_WF_CONNECTION)

			_conn_request_state(tconn, NS(conn, C_DISCONNECTING), CS_HARD);

		spin_unlock_irq(&tconn->req_lock);

		return SS_SUCCESS;

	}



	rv = conn_request_state(tconn, NS(conn, C_DISCONNECTING), 0);



	switch (rv) {

	case SS_NOTHING_TO_DO:

	case SS_ALREADY_STANDALONE:

		return SS_SUCCESS;

	case SS_PRIMARY_NOP:

		/* Our state checking code wants to see the peer outdated. */

		rv = conn_request_state(tconn, NS2(conn, C_DISCONNECTING,

							pdsk, D_OUTDATED), CS_VERBOSE);

		break;

	case SS_CW_FAILED_BY_PEER:

		/* The peer probably wants to see us outdated. */

		rv = conn_request_state(tconn, NS2(conn, C_DISCONNECTING,

							disk, D_OUTDATED), 0);

		if (rv == SS_IS_DISKLESS || rv == SS_LOWER_THAN_OUTDATED) {

			conn_request_state(tconn, NS(conn, C_DISCONNECTING), CS_HARD);

			rv = SS_SUCCESS;

		}

		break;

	default:;

		/* no special handling necessary */

	}



	return rv;

}



int drbd_adm_disconnect(struct sk_buff *skb, struct genl_info *info)

{

	struct disconnect_parms parms;

	struct drbd_tconn *tconn;

	enum drbd_state_rv rv;

	enum drbd_ret_code retcode;

	int err;
@@ -1704,35 +1749,8 @@ int drbd_adm_disconnect(struct sk_buff *skb, struct genl_info *info) 
		}

	}



	if (parms.force_disconnect) {

		spin_lock_irq(&tconn->req_lock);

		if (tconn->cstate >= C_WF_CONNECTION)

			_conn_request_state(tconn, NS(conn, C_DISCONNECTING), CS_HARD);

		spin_unlock_irq(&tconn->req_lock);

		goto done;

	}



	retcode = conn_request_state(tconn, NS(conn, C_DISCONNECTING), 0);



	if (retcode == SS_NOTHING_TO_DO)

		goto done;

	else if (retcode == SS_ALREADY_STANDALONE)

		goto done;

	else if (retcode == SS_PRIMARY_NOP) {

		/* Our state checking code wants to see the peer outdated. */

		retcode = conn_request_state(tconn, NS2(conn, C_DISCONNECTING,

							pdsk, D_OUTDATED), CS_VERBOSE);

	} else if (retcode == SS_CW_FAILED_BY_PEER) {

		/* The peer probably wants to see us outdated. */

		retcode = conn_request_state(tconn, NS2(conn, C_DISCONNECTING,

							disk, D_OUTDATED), 0);

		if (retcode == SS_IS_DISKLESS || retcode == SS_LOWER_THAN_OUTDATED) {

			conn_request_state(tconn, NS(conn, C_DISCONNECTING), CS_HARD);

			retcode = SS_SUCCESS;

		}

	}



	if (retcode < SS_SUCCESS)

	rv = conn_try_disconnect(tconn, parms.force_disconnect);

	if (rv < SS_SUCCESS)

		goto fail;



	if (wait_event_interruptible(tconn->ping_wait,
@@ -1743,7 +1761,6 @@ int drbd_adm_disconnect(struct sk_buff *skb, struct genl_info *info) 
		goto fail;

	}



 done:

	retcode = NO_ERROR;

 fail:

	drbd_adm_finish(info, retcode);
@@ -2644,9 +2661,21 @@ int drbd_adm_add_minor(struct sk_buff *skb, struct genl_info *info) 
	return 0;

}



static enum drbd_ret_code adm_delete_minor(struct drbd_conf *mdev)

{

	if (mdev->state.disk == D_DISKLESS &&

	    /* no need to be mdev->state.conn == C_STANDALONE &&

	     * we may want to delete a minor from a live replication group.

	     */

	    mdev->state.role == R_SECONDARY) {

		drbd_delete_device(mdev_to_minor(mdev));

		return NO_ERROR;

	} else

		return ERR_MINOR_CONFIGURED;

}



int drbd_adm_delete_minor(struct sk_buff *skb, struct genl_info *info)

{

	struct drbd_conf *mdev;

	enum drbd_ret_code retcode;



	retcode = drbd_adm_prepare(skb, info, DRBD_ADM_NEED_MINOR);
@@ -2655,19 +2684,89 @@ int drbd_adm_delete_minor(struct sk_buff *skb, struct genl_info *info) 
	if (retcode != NO_ERROR)

		goto out;



	mdev = adm_ctx.mdev;

	if (mdev->state.disk == D_DISKLESS &&

	    /* no need to be mdev->state.conn == C_STANDALONE &&

	     * we may want to delete a minor from a live replication group.

	     */

	    mdev->state.role == R_SECONDARY) {

		drbd_delete_device(mdev_to_minor(mdev));

		retcode = NO_ERROR;

	mutex_lock(&drbd_cfg_mutex);

	retcode = adm_delete_minor(adm_ctx.mdev);

	mutex_unlock(&drbd_cfg_mutex);

	/* if this was the last volume of this connection,

	 * this will terminate all threads */

	if (retcode == NO_ERROR)

		conn_reconfig_done(adm_ctx.tconn);

	} else

		retcode = ERR_MINOR_CONFIGURED;

out:

	drbd_adm_finish(info, retcode);

	return 0;

}



int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)

{

	enum drbd_ret_code retcode;

	enum drbd_state_rv rv;

	struct drbd_conf *mdev;

	unsigned i;



	retcode = drbd_adm_prepare(skb, info, 0);

	if (!adm_ctx.reply_skb)

		return retcode;

	if (retcode != NO_ERROR)

		goto out;



	if (!adm_ctx.tconn) {

		retcode = ERR_CONN_NOT_KNOWN;

		goto out;

	}



	mutex_lock(&drbd_cfg_mutex);

	/* demote */

	idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {

		retcode = drbd_set_role(mdev, R_SECONDARY, 0);

		if (retcode < SS_SUCCESS) {

			drbd_msg_put_info("failed to demote");

			goto out_unlock;

		}

	}



	/* disconnect */

	rv = conn_try_disconnect(adm_ctx.tconn, 0);

	if (rv < SS_SUCCESS) {

		retcode = rv; /* enum type mismatch! */

		drbd_msg_put_info("failed to disconnect");

		goto out_unlock;

	}



	/* detach */

	idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {

		rv = adm_detach(mdev);

		if (rv < SS_SUCCESS) {

			retcode = rv; /* enum type mismatch! */

			drbd_msg_put_info("failed to detach");

			goto out_unlock;

		}

	}



	/* delete volumes */

	idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {

		retcode = adm_delete_minor(mdev);

		if (retcode != NO_ERROR) {

			/* "can not happen" */

			drbd_msg_put_info("failed to delete volume");

			goto out_unlock;

		}

	}



	/* stop all threads */

	conn_reconfig_done(adm_ctx.tconn);



	/* delete connection */

	if (conn_lowest_minor(adm_ctx.tconn) < 0) {

		drbd_free_tconn(adm_ctx.tconn);

		retcode = NO_ERROR;

	} else {

		/* "can not happen" */

		retcode = ERR_CONN_IN_USE;

		drbd_msg_put_info("failed to delete connection");

		goto out_unlock;

	}

out_unlock:

	mutex_unlock(&drbd_cfg_mutex);

out:

	drbd_adm_finish(info, retcode);

	return 0;
@@ -2683,12 +2782,14 @@ int drbd_adm_delete_connection(struct sk_buff *skb, struct genl_info *info) 
	if (retcode != NO_ERROR)

		goto out;



	mutex_lock(&drbd_cfg_mutex);

	if (conn_lowest_minor(adm_ctx.tconn) < 0) {

		drbd_free_tconn(adm_ctx.tconn);

		retcode = NO_ERROR;

	} else {

		retcode = ERR_CONN_IN_USE;

	}

	mutex_unlock(&drbd_cfg_mutex);



out:

	drbd_adm_finish(info, retcode);

include/linux/drbd_genl.h

+2 −0
Original line number Diff line number Diff line
@@ -347,3 +347,5 @@ GENL_op(DRBD_ADM_OUTDATE, 25, GENL_doit(drbd_adm_outdate), 
	GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, GENLA_F_REQUIRED))

GENL_op(DRBD_ADM_GET_TIMEOUT_TYPE, 26, GENL_doit(drbd_adm_get_timeout_type),

	GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, GENLA_F_REQUIRED))

GENL_op(DRBD_ADM_DOWN,		27, GENL_doit(drbd_adm_down),

	GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, GENLA_F_REQUIRED))