Commit 543cc10b authored by Lars Ellenberg's avatar Lars Ellenberg Committed by Philipp Reisner
Browse files

drbd: drbd_adm_get_status needs to show some more detail 



We want to see existing connection objects, even if they do not
currently have volumes attached.

Change the .dumpit variant of drbd_adm_get_status to iterate not over
minor devices, but over connections + volumes.

Signed-off-by: default avatarPhilipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: default avatarLars Ellenberg <lars.ellenberg@linbit.com>
parent 73d901b7

drivers/block/drbd/drbd_int.h

+2 −1
Original line number Diff line number Diff line
@@ -171,6 +171,7 @@ drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) { 
extern struct ratelimit_state drbd_ratelimit_state;

extern struct idr minors;

extern struct list_head drbd_tconns;

extern struct mutex drbd_cfg_mutex;



/* on the wire */

enum drbd_packet {
@@ -918,7 +919,7 @@ enum { 


struct drbd_tconn {			/* is a resource from the config file */

	char *name;			/* Resource name */

	struct list_head all_tconn;	/* List of all drbd_tconn, prot by global_state_lock */

	struct list_head all_tconn;	/* linked on global drbd_tconns */

	struct idr volumes;		/* <tconn, vnr> to mdev mapping */

	enum drbd_conns cstate;		/* Only C_STANDALONE to C_WF_REPORT_PARAMS */

	struct mutex cstate_mutex;	/* Protects graceful disconnects */

drivers/block/drbd/drbd_main.c

+8 −7
Original line number Diff line number Diff line
@@ -120,6 +120,7 @@ module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0 
 */

struct idr minors;

struct list_head drbd_tconns;  /* list of struct drbd_tconn */

DEFINE_MUTEX(drbd_cfg_mutex);



struct kmem_cache *drbd_request_cache;

struct kmem_cache *drbd_ee_cache;	/* peer requests */
@@ -2238,14 +2239,14 @@ struct drbd_tconn *conn_by_name(const char *name) 
	if (!name || !name[0])

		return NULL;



	write_lock_irq(&global_state_lock);

	mutex_lock(&drbd_cfg_mutex);

	list_for_each_entry(tconn, &drbd_tconns, all_tconn) {

		if (!strcmp(tconn->name, name))

			goto found;

	}

	tconn = NULL;

found:

	write_unlock_irq(&global_state_lock);

	mutex_unlock(&drbd_cfg_mutex);

	return tconn;

}
@@ -2285,9 +2286,9 @@ struct drbd_tconn *drbd_new_tconn(const char *name) 
	drbd_thread_init(tconn, &tconn->worker, drbd_worker, "worker");

	drbd_thread_init(tconn, &tconn->asender, drbd_asender, "asender");



	write_lock_irq(&global_state_lock);

	list_add(&tconn->all_tconn, &drbd_tconns);

	write_unlock_irq(&global_state_lock);

	mutex_lock(&drbd_cfg_mutex);

	list_add_tail(&tconn->all_tconn, &drbd_tconns);

	mutex_unlock(&drbd_cfg_mutex);



	return tconn;
@@ -2302,9 +2303,9 @@ struct drbd_tconn *drbd_new_tconn(const char *name) 


void drbd_free_tconn(struct drbd_tconn *tconn)

{

	write_lock_irq(&global_state_lock);

	mutex_lock(&drbd_cfg_mutex);

	list_del(&tconn->all_tconn);

	write_unlock_irq(&global_state_lock);

	mutex_unlock(&drbd_cfg_mutex);

	idr_destroy(&tconn->volumes);



	free_cpumask_var(tconn->cpu_mask);

drivers/block/drbd/drbd_nl.c

+97 −20
Original line number Diff line number Diff line
@@ -1544,6 +1544,10 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info) 


	new_my_addr = (struct sockaddr *)&new_conf->my_addr;

	new_peer_addr = (struct sockaddr *)&new_conf->peer_addr;



	/* No need to take drbd_cfg_mutex here.  All reconfiguration is

	 * strictly serialized on genl_lock(). We are protected against

	 * concurrent reconfiguration/addition/deletion */

	list_for_each_entry(oconn, &drbd_tconns, all_tconn) {

		if (oconn == tconn)

			continue;
@@ -2187,6 +2191,24 @@ int drbd_adm_outdate(struct sk_buff *skb, struct genl_info *info) 
	return drbd_adm_simple_request_state(skb, info, NS(disk, D_OUTDATED));

}



int nla_put_drbd_cfg_context(struct sk_buff *skb, const char *conn_name, unsigned vnr)

{

	struct nlattr *nla;

	nla = nla_nest_start(skb, DRBD_NLA_CFG_CONTEXT);

	if (!nla)

		goto nla_put_failure;

	if (vnr != VOLUME_UNSPECIFIED)

		NLA_PUT_U32(skb, T_ctx_volume, vnr);

	NLA_PUT_STRING(skb, T_ctx_conn_name, conn_name);

	nla_nest_end(skb, nla);

	return 0;



nla_put_failure:

	if (nla)

		nla_nest_cancel(skb, nla);

	return -EMSGSIZE;

}



int nla_put_status_info(struct sk_buff *skb, struct drbd_conf *mdev,

		const struct sib_info *sib)

{
@@ -2215,12 +2237,8 @@ int nla_put_status_info(struct sk_buff *skb, struct drbd_conf *mdev, 


	/* We need to add connection name and volume number information still.

	 * Minor number is in drbd_genlmsghdr. */

	nla = nla_nest_start(skb, DRBD_NLA_CFG_CONTEXT);

	if (!nla)

	if (nla_put_drbd_cfg_context(skb, mdev->tconn->name, mdev->vnr))

		goto nla_put_failure;

	NLA_PUT_U32(skb, T_ctx_volume, mdev->vnr);

	NLA_PUT_STRING(skb, T_ctx_conn_name, mdev->tconn->name);

	nla_nest_end(skb, nla);



	if (got_ldev)

		if (disk_conf_to_skb(skb, &mdev->ldev->dc, exclude_sensitive))
@@ -2307,41 +2325,100 @@ int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb) 
{

	struct drbd_conf *mdev;

	struct drbd_genlmsghdr *dh;

	int minor = cb->args[0];



	/* Open coded deferred single idr_for_each_entry iteration.

	struct drbd_tconn *pos = (struct drbd_tconn*)cb->args[0];

	struct drbd_tconn *tconn = NULL;

	struct drbd_tconn *tmp;

	unsigned volume = cb->args[1];



	/* Open coded, deferred, iteration:

	 * list_for_each_entry_safe(tconn, tmp, &drbd_tconns, all_tconn) {

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

	 *	  ...

	 *	}

	 * }

	 * where tconn is cb->args[0];

	 * and i is cb->args[1];

	 *

	 * This may miss entries inserted after this dump started,

	 * or entries deleted before they are reached.

	 * But we need to make sure the mdev won't disappear while

	 * we are looking at it. */

	 *

	 * We need to make sure the mdev won't disappear while

	 * we are looking at it, and revalidate our iterators

	 * on each iteration.

	 */



	/* synchronize with drbd_new_tconn/drbd_free_tconn */

	mutex_lock(&drbd_cfg_mutex);

	/* synchronize with drbd_delete_device */

	rcu_read_lock();

	mdev = idr_get_next(&minors, &minor);

	if (mdev) {

next_tconn:

	/* revalidate iterator position */

	list_for_each_entry(tmp, &drbd_tconns, all_tconn) {

		if (pos == NULL) {

			/* first iteration */

			pos = tmp;

			tconn = pos;

			break;

		}

		if (tmp == pos) {

			tconn = pos;

			break;

		}

	}

	if (tconn) {

		mdev = idr_get_next(&tconn->volumes, &volume);

		if (!mdev) {

			/* No more volumes to dump on this tconn.

			 * Advance tconn iterator. */

			pos = list_entry(tconn->all_tconn.next,

					struct drbd_tconn, all_tconn);

			/* But, did we dump any volume on this tconn yet? */

			if (volume != 0) {

				tconn = NULL;

				volume = 0;

				goto next_tconn;

			}

		}



		dh = genlmsg_put(skb, NETLINK_CB(cb->skb).pid,

				cb->nlh->nlmsg_seq, &drbd_genl_family,

				NLM_F_MULTI, DRBD_ADM_GET_STATUS);

		if (!dh)

			goto errout;

			goto out;



		D_ASSERT(mdev->minor == minor);

		if (!mdev) {

			/* this is a tconn without a single volume */

			dh->minor = -1U;

			dh->ret_code = NO_ERROR;

			if (nla_put_drbd_cfg_context(skb, tconn->name, VOLUME_UNSPECIFIED))

				genlmsg_cancel(skb, dh);

			else

				genlmsg_end(skb, dh);

			goto out;

		}



		D_ASSERT(mdev->vnr == volume);

		D_ASSERT(mdev->tconn == tconn);



		dh->minor = minor;

		dh->minor = mdev_to_minor(mdev);

		dh->ret_code = NO_ERROR;



		if (nla_put_status_info(skb, mdev, NULL)) {

			genlmsg_cancel(skb, dh);

			goto errout;

			goto out;

		}

		genlmsg_end(skb, dh);

        }



errout:

out:

	rcu_read_unlock();

	/* where to start idr_get_next with the next iteration */

        cb->args[0] = minor+1;

	mutex_unlock(&drbd_cfg_mutex);

	/* where to start the next iteration */

        cb->args[0] = (long)pos;

        cb->args[1] = (pos == tconn) ? volume + 1 : 0;



	/* No more minors found: empty skb. Which will terminate the dump. */

	/* No more tconns/volumes/minors found results in an empty skb.

	 * Which will terminate the dump. */

        return skb->len;

}