[linux-2.6-block.git] / fs / orangefs / waitqueue.c

/*
 * (C) 2001 Clemson University and The University of Chicago
 * (C) 2011 Omnibond Systems
 *
 * Changes by Acxiom Corporation to implement generic service_operation()
 * function, Copyright Acxiom Corporation, 2005.
 *
 * See COPYING in top-level directory.
 */

/*
 *  In-kernel waitqueue operations.
 */

#include "protocol.h"
#include "orangefs-kernel.h"
#include "orangefs-bufmap.h"

static int wait_for_matching_downcall(struct orangefs_kernel_op_s *);
static void orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *);

/*
 * What we do in this function is to walk the list of operations that are
 * present in the request queue and mark them as purged.
 * NOTE: This is called from the device close after client-core has
 * guaranteed that no new operations could appear on the list since the
 * client-core is anyway going to exit.
 */
void purge_waiting_ops(void)
{
	struct orangefs_kernel_op_s *op;

	spin_lock(&orangefs_request_list_lock);
	list_for_each_entry(op, &orangefs_request_list, list) {
		gossip_debug(GOSSIP_WAIT_DEBUG,
			     "pvfs2-client-core: purging op tag %llu %s\n",
			     llu(op->tag),
			     get_opname_string(op));
		set_op_state_purged(op);
	}
	spin_unlock(&orangefs_request_list_lock);
}

/*
 * submits a ORANGEFS operation and waits for it to complete
 *
 * Note op->downcall.status will contain the status of the operation (in
 * errno format), whether provided by pvfs2-client or a result of failure to
 * service the operation.  If the caller wishes to distinguish, then
 * op->state can be checked to see if it was serviced or not.
 *
 * Returns contents of op->downcall.status for convenience
 */
int service_operation(struct orangefs_kernel_op_s *op,
		      const char *op_name,
		      int flags)
{
	/* flags to modify behavior */
	sigset_t orig_sigset;
	int ret = 0;

	DEFINE_WAIT(wait_entry);

	op->upcall.tgid = current->tgid;
	op->upcall.pid = current->pid;

retry_servicing:
	op->downcall.status = 0;
	gossip_debug(GOSSIP_WAIT_DEBUG,
		     "orangefs: service_operation: %s %p\n",
		     op_name,
		     op);
	gossip_debug(GOSSIP_WAIT_DEBUG,
		     "orangefs: operation posted by process: %s, pid: %i\n",
		     current->comm,
		     current->pid);

	/* mask out signals if this operation is not to be interrupted */
	if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
		orangefs_block_signals(&orig_sigset);

	if (!(flags & ORANGEFS_OP_NO_SEMAPHORE)) {
		ret = mutex_lock_interruptible(&request_mutex);
		/*
		 * check to see if we were interrupted while waiting for
		 * semaphore
		 */
		if (ret < 0) {
			if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
				orangefs_set_signals(&orig_sigset);
			op->downcall.status = ret;
			gossip_debug(GOSSIP_WAIT_DEBUG,
				     "orangefs: service_operation interrupted.\n");
			return ret;
		}
	}

	/* queue up the operation */
	spin_lock(&orangefs_request_list_lock);
	spin_lock(&op->lock);
	set_op_state_waiting(op);
	if (flags & ORANGEFS_OP_PRIORITY)
		list_add(&op->list, &orangefs_request_list);
	else
		list_add_tail(&op->list, &orangefs_request_list);
	spin_unlock(&op->lock);
	wake_up_interruptible(&orangefs_request_list_waitq);
	if (!__is_daemon_in_service()) {
		/*
		 * By incrementing the per-operation attempt counter, we
		 * directly go into the timeout logic while waiting for
		 * the matching downcall to be read
		 */
		gossip_debug(GOSSIP_WAIT_DEBUG,
			     "%s:client core is NOT in service.\n",
			     __func__);
		op->attempts++;
	}
	spin_unlock(&orangefs_request_list_lock);

	if (!(flags & ORANGEFS_OP_NO_SEMAPHORE))
		mutex_unlock(&request_mutex);

	/*
	 * If we are asked to service an asynchronous operation from
	 * VFS perspective, we are done.
	 */
	if (flags & ORANGEFS_OP_ASYNC)
		return 0;

	ret = wait_for_matching_downcall(op);

	if (ret < 0) {
		/* failed to get matching downcall */
		if (ret == -ETIMEDOUT) {
			gossip_err("orangefs: %s -- wait timed out; aborting attempt.\n",
				   op_name);
		}
		orangefs_clean_up_interrupted_operation(op);
		op->downcall.status = ret;
	} else {
		spin_unlock(&op->lock);
		/* got matching downcall; make sure status is in errno format */
		op->downcall.status =
		    orangefs_normalize_to_errno(op->downcall.status);
		ret = op->downcall.status;
	}

	if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
		orangefs_set_signals(&orig_sigset);

	BUG_ON(ret != op->downcall.status);
	/* retry if operation has not been serviced and if requested */
	if (!op_state_serviced(op) && op->downcall.status == -EAGAIN) {
		gossip_debug(GOSSIP_WAIT_DEBUG,
			     "orangefs: tag %llu (%s)"
			     " -- operation to be retried (%d attempt)\n",
			     llu(op->tag),
			     op_name,
			     op->attempts + 1);

		if (!op->uses_shared_memory)
			/*
			 * this operation doesn't use the shared memory
			 * system
			 */
			goto retry_servicing;

		/* op uses shared memory */
		if (orangefs_get_bufmap_init() == 0) {
			WARN_ON(1);
			/*
			 * This operation uses the shared memory system AND
			 * the system is not yet ready. This situation occurs
			 * when the client-core is restarted AND there were
			 * operations waiting to be processed or were already
			 * in process.
			 */
			gossip_debug(GOSSIP_WAIT_DEBUG,
				     "uses_shared_memory is true.\n");
			gossip_debug(GOSSIP_WAIT_DEBUG,
				     "Client core in-service status(%d).\n",
				     is_daemon_in_service());
			gossip_debug(GOSSIP_WAIT_DEBUG, "bufmap_init:%d.\n",
				     orangefs_get_bufmap_init());
			gossip_debug(GOSSIP_WAIT_DEBUG,
				     "operation's status is 0x%0x.\n",
				     op->op_state);

			/*
			 * let process sleep for a few seconds so shared
			 * memory system can be initialized.
			 */
			prepare_to_wait(&orangefs_bufmap_init_waitq,
					&wait_entry,
					TASK_INTERRUPTIBLE);

			/*
			 * Wait for orangefs_bufmap_initialize() to wake me up
			 * within the allotted time.
			 */
			ret = schedule_timeout(
				ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ);

			gossip_debug(GOSSIP_WAIT_DEBUG,
				     "Value returned from schedule_timeout:"
				     "%d.\n",
				     ret);
			gossip_debug(GOSSIP_WAIT_DEBUG,
				     "Is shared memory available? (%d).\n",
				     orangefs_get_bufmap_init());

			finish_wait(&orangefs_bufmap_init_waitq, &wait_entry);

			if (orangefs_get_bufmap_init() == 0) {
				gossip_err("%s:The shared memory system has not started in %d seconds after the client core restarted.  Aborting user's request(%s).\n",
					   __func__,
					   ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS,
					   get_opname_string(op));
				return -EIO;
			}

			/*
			 * Return to the calling function and re-populate a
			 * shared memory buffer.
			 */
			return -EAGAIN;
		}
	}

	gossip_debug(GOSSIP_WAIT_DEBUG,
		     "orangefs: service_operation %s returning: %d for %p.\n",
		     op_name,
		     ret,
		     op);
	return ret;
}

bool orangefs_cancel_op_in_progress(struct orangefs_kernel_op_s *op)
{
	u64 tag = op->tag;
	if (!op_state_in_progress(op))
		return false;

	op->slot_to_free = op->upcall.req.io.buf_index;
	memset(&op->upcall, 0, sizeof(op->upcall));
	memset(&op->downcall, 0, sizeof(op->downcall));
	op->upcall.type = ORANGEFS_VFS_OP_CANCEL;
	op->upcall.req.cancel.op_tag = tag;
	op->downcall.type = ORANGEFS_VFS_OP_INVALID;
	op->downcall.status = -1;
	orangefs_new_tag(op);

	spin_lock(&orangefs_request_list_lock);
	/* orangefs_request_list_lock is enough of a barrier here */
	if (!__is_daemon_in_service()) {
		spin_unlock(&orangefs_request_list_lock);
		return false;
	}
	spin_lock(&op->lock);
	set_op_state_waiting(op);
	list_add(&op->list, &orangefs_request_list);
	spin_unlock(&op->lock);
	spin_unlock(&orangefs_request_list_lock);

	gossip_debug(GOSSIP_UTILS_DEBUG,
		     "Attempting ORANGEFS operation cancellation of tag %llu\n",
		     llu(tag));
	return true;
}

static void orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op)
{
	/*
	 * handle interrupted cases depending on what state we were in when
	 * the interruption is detected.  there is a coarse grained lock
	 * across the operation.
	 *
	 * Called with op->lock held.
	 */
	op->op_state |= OP_VFS_STATE_GIVEN_UP;

	if (op_state_waiting(op)) {
		/*
		 * upcall hasn't been read; remove op from upcall request
		 * list.
		 */
		spin_unlock(&op->lock);
		spin_lock(&orangefs_request_list_lock);
		list_del(&op->list);
		spin_unlock(&orangefs_request_list_lock);
		gossip_debug(GOSSIP_WAIT_DEBUG,
			     "Interrupted: Removed op %p from request_list\n",
			     op);
	} else if (op_state_in_progress(op)) {
		/* op must be removed from the in progress htable */
		spin_unlock(&op->lock);
		spin_lock(&htable_ops_in_progress_lock);
		list_del(&op->list);
		spin_unlock(&htable_ops_in_progress_lock);
		gossip_debug(GOSSIP_WAIT_DEBUG,
			     "Interrupted: Removed op %p"
			     " from htable_ops_in_progress\n",
			     op);
	} else if (!op_state_serviced(op)) {
		spin_unlock(&op->lock);
		gossip_err("interrupted operation is in a weird state 0x%x\n",
			   op->op_state);
	} else {
		/*
		 * It is not intended for execution to flow here,
		 * but having this unlock here makes sparse happy.
		 */
		gossip_err("%s: can't get here.\n", __func__);
		spin_unlock(&op->lock);
	}
	reinit_completion(&op->waitq);
}

/*
 * sleeps on waitqueue waiting for matching downcall.
 * if client-core finishes servicing, then we are good to go.
 * else if client-core exits, we get woken up here, and retry with a timeout
 *
 * Post when this call returns to the caller, the specified op will no
 * longer be on any list or htable.
 *
 * Returns 0 on success and -errno on failure
 * Errors are:
 * EAGAIN in case we want the caller to requeue and try again..
 * EINTR/EIO/ETIMEDOUT indicating we are done trying to service this
 * operation since client-core seems to be exiting too often
 * or if we were interrupted.
 *
 * Returns with op->lock taken.
 */
static int wait_for_matching_downcall(struct orangefs_kernel_op_s *op)
{
	long timeout, n;

	timeout = op->attempts ? op_timeout_secs * HZ : MAX_SCHEDULE_TIMEOUT;
	n = wait_for_completion_interruptible_timeout(&op->waitq, timeout);
	spin_lock(&op->lock);

	if (op_state_serviced(op))
		return 0;

	if (unlikely(n < 0)) {
		gossip_debug(GOSSIP_WAIT_DEBUG,
			     "*** %s:"
			     " operation interrupted by a signal (tag "
			     "%llu, op %p)\n",
			     __func__,
			     llu(op->tag),
			     op);
		return -EINTR;
	}
	op->attempts++;
	if (op_state_purged(op)) {
		gossip_debug(GOSSIP_WAIT_DEBUG,
			     "*** %s:"
			     " operation purged (tag "
			     "%llu, %p, att %d)\n",
			     __func__,
			     llu(op->tag),
			     op,
			     op->attempts);
		return (op->attempts < ORANGEFS_PURGE_RETRY_COUNT) ?
			 -EAGAIN :
			 -EIO;
	}
	/* must have timed out, then... */
	gossip_debug(GOSSIP_WAIT_DEBUG,
		     "*** %s:"
		     " operation timed out (tag"
		     " %llu, %p, att %d)\n",
		     __func__,
		     llu(op->tag),
		     op,
		     op->attempts);
	return -ETIMEDOUT;
}
Commit	Line	Data
1182fca3 MM	1	/*
	2	* (C) 2001 Clemson University and The University of Chicago
	3	* (C) 2011 Omnibond Systems
	4	*
	5	* Changes by Acxiom Corporation to implement generic service_operation()
	6	* function, Copyright Acxiom Corporation, 2005.
	7	*
	8	* See COPYING in top-level directory.
	9	*/
	10
	11	/*
	12	* In-kernel waitqueue operations.
	13	*/
	14
	15	#include "protocol.h"
575e9461 MM	16	#include "orangefs-kernel.h"
575e9461 MM	17	#include "orangefs-bufmap.h"
1182fca3	18
ade3d781	19	static int wait_for_matching_downcall(struct orangefs_kernel_op_s *);
d2d87a3b	20	static void orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *);
ade3d781	21
1182fca3 MM	22	/*
	23	* What we do in this function is to walk the list of operations that are
	24	* present in the request queue and mark them as purged.
	25	* NOTE: This is called from the device close after client-core has
	26	* guaranteed that no new operations could appear on the list since the
	27	* client-core is anyway going to exit.
	28	*/
	29	void purge_waiting_ops(void)
	30	{
8bb8aefd	31	struct orangefs_kernel_op_s *op;
1182fca3	32
8bb8aefd YL	33	spin_lock(&orangefs_request_list_lock);
8bb8aefd YL	34	list_for_each_entry(op, &orangefs_request_list, list) {
1182fca3 MM	35	gossip_debug(GOSSIP_WAIT_DEBUG,
	36	"pvfs2-client-core: purging op tag %llu %s\n",
	37	llu(op->tag),
	38	get_opname_string(op));
1182fca3	39	set_op_state_purged(op);
1182fca3	40	}
8bb8aefd	41	spin_unlock(&orangefs_request_list_lock);
1182fca3 MM	42	}
	43
	44	/*
8bb8aefd	45	* submits a ORANGEFS operation and waits for it to complete
1182fca3 MM	46	*
	47	* Note op->downcall.status will contain the status of the operation (in
	48	* errno format), whether provided by pvfs2-client or a result of failure to
	49	* service the operation. If the caller wishes to distinguish, then
	50	* op->state can be checked to see if it was serviced or not.
	51	*
	52	* Returns contents of op->downcall.status for convenience
	53	*/
8bb8aefd	54	int service_operation(struct orangefs_kernel_op_s *op,
1182fca3 MM	55	const char *op_name,
	56	int flags)
	57	{
	58	/* flags to modify behavior */
	59	sigset_t orig_sigset;
	60	int ret = 0;
	61
ce6c414e	62	DEFINE_WAIT(wait_entry);
1182fca3 MM	63
	64	op->upcall.tgid = current->tgid;
	65	op->upcall.pid = current->pid;
	66
	67	retry_servicing:
	68	op->downcall.status = 0;
	69	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	70	"orangefs: service_operation: %s %p\n",
1182fca3 MM	71	op_name,
	72	op);
	73	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	74	"orangefs: operation posted by process: %s, pid: %i\n",
1182fca3 MM	75	current->comm,
	76	current->pid);
	77
	78	/* mask out signals if this operation is not to be interrupted */
8bb8aefd	79	if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
c146c0b8	80	orangefs_block_signals(&orig_sigset);
1182fca3	81
8bb8aefd	82	if (!(flags & ORANGEFS_OP_NO_SEMAPHORE)) {
1182fca3 MM	83	ret = mutex_lock_interruptible(&request_mutex);
	84	/*
	85	* check to see if we were interrupted while waiting for
	86	* semaphore
	87	*/
	88	if (ret < 0) {
8bb8aefd	89	if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
c146c0b8	90	orangefs_set_signals(&orig_sigset);
1182fca3 MM	91	op->downcall.status = ret;
1182fca3 MM	92	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	93	"orangefs: service_operation interrupted.\n");
1182fca3 MM	94	return ret;
	95	}
	96	}
	97
98815ade AV	98	/* queue up the operation */
	99	spin_lock(&orangefs_request_list_lock);
	100	spin_lock(&op->lock);
	101	set_op_state_waiting(op);
	102	if (flags & ORANGEFS_OP_PRIORITY)
	103	list_add(&op->list, &orangefs_request_list);
	104	else
	105	list_add_tail(&op->list, &orangefs_request_list);
	106	spin_unlock(&op->lock);
	107	wake_up_interruptible(&orangefs_request_list_waitq);
	108	if (!__is_daemon_in_service()) {
1182fca3 MM	109	/*
	110	* By incrementing the per-operation attempt counter, we
	111	* directly go into the timeout logic while waiting for
	112	* the matching downcall to be read
	113	*/
	114	gossip_debug(GOSSIP_WAIT_DEBUG,
98815ade	115	"%s:client core is NOT in service.\n",
1182fca3	116	__func__);
98815ade	117	op->attempts++;
1182fca3	118	}
98815ade	119	spin_unlock(&orangefs_request_list_lock);
1182fca3	120
8bb8aefd	121	if (!(flags & ORANGEFS_OP_NO_SEMAPHORE))
1182fca3 MM	122	mutex_unlock(&request_mutex);
	123
	124	/*
	125	* If we are asked to service an asynchronous operation from
	126	* VFS perspective, we are done.
	127	*/
8bb8aefd	128	if (flags & ORANGEFS_OP_ASYNC)
1182fca3 MM	129	return 0;
1182fca3 MM	130
78699e29	131	ret = wait_for_matching_downcall(op);
1182fca3 MM	132
	133	if (ret < 0) {
	134	/* failed to get matching downcall */
	135	if (ret == -ETIMEDOUT) {
8bb8aefd	136	gossip_err("orangefs: %s -- wait timed out; aborting attempt.\n",
1182fca3 MM	137	op_name);
1182fca3 MM	138	}
d2d87a3b	139	orangefs_clean_up_interrupted_operation(op);
1182fca3 MM	140	op->downcall.status = ret;
1182fca3 MM	141	} else {
d2d87a3b	142	spin_unlock(&op->lock);
1182fca3 MM	143	/* got matching downcall; make sure status is in errno format */
1182fca3 MM	144	op->downcall.status =
8bb8aefd	145	orangefs_normalize_to_errno(op->downcall.status);
1182fca3 MM	146	ret = op->downcall.status;
	147	}
	148
8bb8aefd	149	if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
c146c0b8	150	orangefs_set_signals(&orig_sigset);
1182fca3 MM	151
	152	BUG_ON(ret != op->downcall.status);
	153	/* retry if operation has not been serviced and if requested */
	154	if (!op_state_serviced(op) && op->downcall.status == -EAGAIN) {
	155	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	156	"orangefs: tag %llu (%s)"
1182fca3 MM	157	" -- operation to be retried (%d attempt)\n",
	158	llu(op->tag),
	159	op_name,
	160	op->attempts + 1);
	161
	162	if (!op->uses_shared_memory)
	163	/*
	164	* this operation doesn't use the shared memory
	165	* system
	166	*/
	167	goto retry_servicing;
	168
	169	/* op uses shared memory */
7d221485	170	if (orangefs_get_bufmap_init() == 0) {
6ebcc3fc	171	WARN_ON(1);
1182fca3 MM	172	/*
	173	* This operation uses the shared memory system AND
	174	* the system is not yet ready. This situation occurs
	175	* when the client-core is restarted AND there were
	176	* operations waiting to be processed or were already
	177	* in process.
	178	*/
	179	gossip_debug(GOSSIP_WAIT_DEBUG,
	180	"uses_shared_memory is true.\n");
	181	gossip_debug(GOSSIP_WAIT_DEBUG,
	182	"Client core in-service status(%d).\n",
	183	is_daemon_in_service());
	184	gossip_debug(GOSSIP_WAIT_DEBUG, "bufmap_init:%d.\n",
7d221485	185	orangefs_get_bufmap_init());
1182fca3 MM	186	gossip_debug(GOSSIP_WAIT_DEBUG,
	187	"operation's status is 0x%0x.\n",
	188	op->op_state);
	189
	190	/*
	191	* let process sleep for a few seconds so shared
	192	* memory system can be initialized.
	193	*/
ce6c414e MM	194	prepare_to_wait(&orangefs_bufmap_init_waitq,
	195	&wait_entry,
	196	TASK_INTERRUPTIBLE);
1182fca3	197
1182fca3	198	/*
8bb8aefd	199	* Wait for orangefs_bufmap_initialize() to wake me up
1182fca3 MM	200	* within the allotted time.
1182fca3 MM	201	*/
727cbfea AV	202	ret = schedule_timeout(
727cbfea AV	203	ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ);
1182fca3 MM	204
	205	gossip_debug(GOSSIP_WAIT_DEBUG,
	206	"Value returned from schedule_timeout:"
	207	"%d.\n",
	208	ret);
	209	gossip_debug(GOSSIP_WAIT_DEBUG,
	210	"Is shared memory available? (%d).\n",
7d221485	211	orangefs_get_bufmap_init());
1182fca3	212
ce6c414e	213	finish_wait(&orangefs_bufmap_init_waitq, &wait_entry);
1182fca3	214
7d221485	215	if (orangefs_get_bufmap_init() == 0) {
1182fca3 MM	216	gossip_err("%s:The shared memory system has not started in %d seconds after the client core restarted. Aborting user's request(%s).\n",
1182fca3 MM	217	__func__,
8bb8aefd	218	ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS,
1182fca3 MM	219	get_opname_string(op));
	220	return -EIO;
	221	}
	222
	223	/*
	224	* Return to the calling function and re-populate a
	225	* shared memory buffer.
	226	*/
	227	return -EAGAIN;
	228	}
	229	}
	230
	231	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	232	"orangefs: service_operation %s returning: %d for %p.\n",
1182fca3 MM	233	op_name,
	234	ret,
	235	op);
	236	return ret;
	237	}
	238
78699e29 AV	239	bool orangefs_cancel_op_in_progress(struct orangefs_kernel_op_s *op)
	240	{
	241	u64 tag = op->tag;
	242	if (!op_state_in_progress(op))
	243	return false;
	244
	245	op->slot_to_free = op->upcall.req.io.buf_index;
	246	memset(&op->upcall, 0, sizeof(op->upcall));
	247	memset(&op->downcall, 0, sizeof(op->downcall));
	248	op->upcall.type = ORANGEFS_VFS_OP_CANCEL;
	249	op->upcall.req.cancel.op_tag = tag;
	250	op->downcall.type = ORANGEFS_VFS_OP_INVALID;
	251	op->downcall.status = -1;
	252	orangefs_new_tag(op);
	253
	254	spin_lock(&orangefs_request_list_lock);
	255	/* orangefs_request_list_lock is enough of a barrier here */
	256	if (!__is_daemon_in_service()) {
	257	spin_unlock(&orangefs_request_list_lock);
	258	return false;
	259	}
98815ade AV	260	spin_lock(&op->lock);
	261	set_op_state_waiting(op);
	262	list_add(&op->list, &orangefs_request_list);
	263	spin_unlock(&op->lock);
78699e29 AV	264	spin_unlock(&orangefs_request_list_lock);
	265
	266	gossip_debug(GOSSIP_UTILS_DEBUG,
	267	"Attempting ORANGEFS operation cancellation of tag %llu\n",
	268	llu(tag));
	269	return true;
	270	}
	271
e07db0a2	272	static void orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op)
1182fca3 MM	273	{
	274	/*
	275	* handle interrupted cases depending on what state we were in when
	276	* the interruption is detected. there is a coarse grained lock
	277	* across the operation.
	278	*
eab9b389	279	* Called with op->lock held.
1182fca3	280	*/
ed42fe05	281	op->op_state \|= OP_VFS_STATE_GIVEN_UP;
1182fca3 MM	282
	283	if (op_state_waiting(op)) {
	284	/*
	285	* upcall hasn't been read; remove op from upcall request
	286	* list.
	287	*/
	288	spin_unlock(&op->lock);
ed42fe05 AV	289	spin_lock(&orangefs_request_list_lock);
	290	list_del(&op->list);
	291	spin_unlock(&orangefs_request_list_lock);
1182fca3 MM	292	gossip_debug(GOSSIP_WAIT_DEBUG,
	293	"Interrupted: Removed op %p from request_list\n",
	294	op);
	295	} else if (op_state_in_progress(op)) {
	296	/* op must be removed from the in progress htable */
	297	spin_unlock(&op->lock);
	298	spin_lock(&htable_ops_in_progress_lock);
	299	list_del(&op->list);
	300	spin_unlock(&htable_ops_in_progress_lock);
	301	gossip_debug(GOSSIP_WAIT_DEBUG,
	302	"Interrupted: Removed op %p"
	303	" from htable_ops_in_progress\n",
	304	op);
	305	} else if (!op_state_serviced(op)) {
	306	spin_unlock(&op->lock);
	307	gossip_err("interrupted operation is in a weird state 0x%x\n",
	308	op->op_state);
84d02150 MM	309	} else {
	310	/*
	311	* It is not intended for execution to flow here,
	312	* but having this unlock here makes sparse happy.
	313	*/
	314	gossip_err("%s: can't get here.\n", __func__);
	315	spin_unlock(&op->lock);
1182fca3	316	}
d2d87a3b	317	reinit_completion(&op->waitq);
1182fca3 MM	318	}
	319
	320	/*
	321	* sleeps on waitqueue waiting for matching downcall.
	322	* if client-core finishes servicing, then we are good to go.
	323	* else if client-core exits, we get woken up here, and retry with a timeout
	324	*
	325	* Post when this call returns to the caller, the specified op will no
	326	* longer be on any list or htable.
	327	*
	328	* Returns 0 on success and -errno on failure
	329	* Errors are:
	330	* EAGAIN in case we want the caller to requeue and try again..
	331	* EINTR/EIO/ETIMEDOUT indicating we are done trying to service this
	332	* operation since client-core seems to be exiting too often
	333	* or if we were interrupted.
d2d87a3b AV	334	*
d2d87a3b AV	335	* Returns with op->lock taken.
1182fca3	336	*/
b7ae37b0	337	static int wait_for_matching_downcall(struct orangefs_kernel_op_s *op)
1182fca3	338	{
d2d87a3b	339	long timeout, n;
1182fca3	340
d2d87a3b AV	341	timeout = op->attempts ? op_timeout_secs * HZ : MAX_SCHEDULE_TIMEOUT;
	342	n = wait_for_completion_interruptible_timeout(&op->waitq, timeout);
	343	spin_lock(&op->lock);
1182fca3	344
d2d87a3b AV	345	if (op_state_serviced(op))
d2d87a3b AV	346	return 0;
70c6ea26	347
d2d87a3b AV	348	if (unlikely(n < 0)) {
	349	gossip_debug(GOSSIP_WAIT_DEBUG,
	350	"*** %s:"
	351	" operation interrupted by a signal (tag "
	352	"%llu, op %p)\n",
	353	__func__,
	354	llu(op->tag),
	355	op);
	356	return -EINTR;
1182fca3	357	}
d2d87a3b AV	358	op->attempts++;
	359	if (op_state_purged(op)) {
	360	gossip_debug(GOSSIP_WAIT_DEBUG,
	361	"*** %s:"
	362	" operation purged (tag "
	363	"%llu, %p, att %d)\n",
	364	__func__,
	365	llu(op->tag),
	366	op,
	367	op->attempts);
	368	return (op->attempts < ORANGEFS_PURGE_RETRY_COUNT) ?
	369	-EAGAIN :
	370	-EIO;
	371	}
	372	/* must have timed out, then... */
	373	gossip_debug(GOSSIP_WAIT_DEBUG,
	374	"*** %s:"
	375	" operation timed out (tag"
	376	" %llu, %p, att %d)\n",
	377	__func__,
	378	llu(op->tag),
	379	op,
	380	op->attempts);
	381	return -ETIMEDOUT;
1182fca3	382	}