[linux-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);
}

static inline void
__add_op_to_request_list(struct orangefs_kernel_op_s *op)
{
	spin_lock(&op->lock);
	set_op_state_waiting(op);
	list_add_tail(&op->list, &orangefs_request_list);
	spin_unlock(&op->lock);
	wake_up_interruptible(&orangefs_request_list_waitq);
}

static inline void
add_op_to_request_list(struct orangefs_kernel_op_s *op)
{
	spin_lock(&orangefs_request_list_lock);
	__add_op_to_request_list(op);
	spin_unlock(&orangefs_request_list_lock);
}

static inline
void add_priority_op_to_request_list(struct orangefs_kernel_op_s *op)
{
	spin_lock(&orangefs_request_list_lock);
	spin_lock(&op->lock);
	set_op_state_waiting(op);

	list_add(&op->list, &orangefs_request_list);
	spin_unlock(&orangefs_request_list_lock);
	spin_unlock(&op->lock);
	wake_up_interruptible(&orangefs_request_list_waitq);
}

/*
 * 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;
		}
	}

	gossip_debug(GOSSIP_WAIT_DEBUG,
		     "%s:About to call is_daemon_in_service().\n",
		     __func__);

	if (is_daemon_in_service() < 0) {
		/*
		 * 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(%d).\n",
			     __func__,
			     is_daemon_in_service());
		op->attempts++;
	}

	/* queue up the operation */
	if (flags & ORANGEFS_OP_PRIORITY) {
		add_priority_op_to_request_list(op);
	} else {
		gossip_debug(GOSSIP_WAIT_DEBUG,
			     "%s:About to call add_op_to_request_list().\n",
			     __func__);
		add_op_to_request_list(op);
	}

	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;
	}
	__add_op_to_request_list(op);
	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	}
1182fca3 MM	43
fc916da5	44	static inline void
78699e29	45	__add_op_to_request_list(struct orangefs_kernel_op_s *op)
fc916da5	46	{
fc916da5 AV	47	spin_lock(&op->lock);
	48	set_op_state_waiting(op);
	49	list_add_tail(&op->list, &orangefs_request_list);
fc916da5 AV	50	spin_unlock(&op->lock);
	51	wake_up_interruptible(&orangefs_request_list_waitq);
	52	}
	53
78699e29 AV	54	static inline void
	55	add_op_to_request_list(struct orangefs_kernel_op_s *op)
	56	{
	57	spin_lock(&orangefs_request_list_lock);
	58	__add_op_to_request_list(op);
	59	spin_unlock(&orangefs_request_list_lock);
	60	}
	61
fc916da5 AV	62	static inline
	63	void add_priority_op_to_request_list(struct orangefs_kernel_op_s *op)
	64	{
	65	spin_lock(&orangefs_request_list_lock);
	66	spin_lock(&op->lock);
	67	set_op_state_waiting(op);
	68
	69	list_add(&op->list, &orangefs_request_list);
	70	spin_unlock(&orangefs_request_list_lock);
	71	spin_unlock(&op->lock);
	72	wake_up_interruptible(&orangefs_request_list_waitq);
	73	}
	74
1182fca3	75	/*
8bb8aefd	76	* submits a ORANGEFS operation and waits for it to complete
1182fca3 MM	77	*
	78	* Note op->downcall.status will contain the status of the operation (in
	79	* errno format), whether provided by pvfs2-client or a result of failure to
	80	* service the operation. If the caller wishes to distinguish, then
	81	* op->state can be checked to see if it was serviced or not.
	82	*
	83	* Returns contents of op->downcall.status for convenience
	84	*/
8bb8aefd	85	int service_operation(struct orangefs_kernel_op_s *op,
1182fca3 MM	86	const char *op_name,
	87	int flags)
	88	{
	89	/* flags to modify behavior */
	90	sigset_t orig_sigset;
	91	int ret = 0;
	92
ce6c414e	93	DEFINE_WAIT(wait_entry);
1182fca3 MM	94
	95	op->upcall.tgid = current->tgid;
	96	op->upcall.pid = current->pid;
	97
	98	retry_servicing:
	99	op->downcall.status = 0;
	100	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	101	"orangefs: service_operation: %s %p\n",
1182fca3 MM	102	op_name,
	103	op);
	104	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	105	"orangefs: operation posted by process: %s, pid: %i\n",
1182fca3 MM	106	current->comm,
	107	current->pid);
	108
	109	/* mask out signals if this operation is not to be interrupted */
8bb8aefd	110	if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
c146c0b8	111	orangefs_block_signals(&orig_sigset);
1182fca3	112
8bb8aefd	113	if (!(flags & ORANGEFS_OP_NO_SEMAPHORE)) {
1182fca3 MM	114	ret = mutex_lock_interruptible(&request_mutex);
	115	/*
	116	* check to see if we were interrupted while waiting for
	117	* semaphore
	118	*/
	119	if (ret < 0) {
8bb8aefd	120	if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
c146c0b8	121	orangefs_set_signals(&orig_sigset);
1182fca3 MM	122	op->downcall.status = ret;
1182fca3 MM	123	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	124	"orangefs: service_operation interrupted.\n");
1182fca3 MM	125	return ret;
	126	}
	127	}
	128
	129	gossip_debug(GOSSIP_WAIT_DEBUG,
	130	"%s:About to call is_daemon_in_service().\n",
	131	__func__);
	132
	133	if (is_daemon_in_service() < 0) {
	134	/*
	135	* By incrementing the per-operation attempt counter, we
	136	* directly go into the timeout logic while waiting for
	137	* the matching downcall to be read
	138	*/
	139	gossip_debug(GOSSIP_WAIT_DEBUG,
	140	"%s:client core is NOT in service(%d).\n",
	141	__func__,
	142	is_daemon_in_service());
	143	op->attempts++;
	144	}
	145
	146	/* queue up the operation */
8bb8aefd	147	if (flags & ORANGEFS_OP_PRIORITY) {
1182fca3 MM	148	add_priority_op_to_request_list(op);
	149	} else {
	150	gossip_debug(GOSSIP_WAIT_DEBUG,
	151	"%s:About to call add_op_to_request_list().\n",
	152	__func__);
	153	add_op_to_request_list(op);
	154	}
	155
8bb8aefd	156	if (!(flags & ORANGEFS_OP_NO_SEMAPHORE))
1182fca3 MM	157	mutex_unlock(&request_mutex);
	158
	159	/*
	160	* If we are asked to service an asynchronous operation from
	161	* VFS perspective, we are done.
	162	*/
8bb8aefd	163	if (flags & ORANGEFS_OP_ASYNC)
1182fca3 MM	164	return 0;
1182fca3 MM	165
78699e29	166	ret = wait_for_matching_downcall(op);
1182fca3 MM	167
	168	if (ret < 0) {
	169	/* failed to get matching downcall */
	170	if (ret == -ETIMEDOUT) {
8bb8aefd	171	gossip_err("orangefs: %s -- wait timed out; aborting attempt.\n",
1182fca3 MM	172	op_name);
1182fca3 MM	173	}
d2d87a3b	174	orangefs_clean_up_interrupted_operation(op);
1182fca3 MM	175	op->downcall.status = ret;
1182fca3 MM	176	} else {
d2d87a3b	177	spin_unlock(&op->lock);
1182fca3 MM	178	/* got matching downcall; make sure status is in errno format */
1182fca3 MM	179	op->downcall.status =
8bb8aefd	180	orangefs_normalize_to_errno(op->downcall.status);
1182fca3 MM	181	ret = op->downcall.status;
	182	}
	183
8bb8aefd	184	if (!(flags & ORANGEFS_OP_INTERRUPTIBLE))
c146c0b8	185	orangefs_set_signals(&orig_sigset);
1182fca3 MM	186
	187	BUG_ON(ret != op->downcall.status);
	188	/* retry if operation has not been serviced and if requested */
	189	if (!op_state_serviced(op) && op->downcall.status == -EAGAIN) {
	190	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	191	"orangefs: tag %llu (%s)"
1182fca3 MM	192	" -- operation to be retried (%d attempt)\n",
	193	llu(op->tag),
	194	op_name,
	195	op->attempts + 1);
	196
	197	if (!op->uses_shared_memory)
	198	/*
	199	* this operation doesn't use the shared memory
	200	* system
	201	*/
	202	goto retry_servicing;
	203
	204	/* op uses shared memory */
7d221485	205	if (orangefs_get_bufmap_init() == 0) {
6ebcc3fc	206	WARN_ON(1);
1182fca3 MM	207	/*
	208	* This operation uses the shared memory system AND
	209	* the system is not yet ready. This situation occurs
	210	* when the client-core is restarted AND there were
	211	* operations waiting to be processed or were already
	212	* in process.
	213	*/
	214	gossip_debug(GOSSIP_WAIT_DEBUG,
	215	"uses_shared_memory is true.\n");
	216	gossip_debug(GOSSIP_WAIT_DEBUG,
	217	"Client core in-service status(%d).\n",
	218	is_daemon_in_service());
	219	gossip_debug(GOSSIP_WAIT_DEBUG, "bufmap_init:%d.\n",
7d221485	220	orangefs_get_bufmap_init());
1182fca3 MM	221	gossip_debug(GOSSIP_WAIT_DEBUG,
	222	"operation's status is 0x%0x.\n",
	223	op->op_state);
	224
	225	/*
	226	* let process sleep for a few seconds so shared
	227	* memory system can be initialized.
	228	*/
ce6c414e MM	229	prepare_to_wait(&orangefs_bufmap_init_waitq,
	230	&wait_entry,
	231	TASK_INTERRUPTIBLE);
1182fca3	232
1182fca3	233	/*
8bb8aefd	234	* Wait for orangefs_bufmap_initialize() to wake me up
1182fca3 MM	235	* within the allotted time.
1182fca3 MM	236	*/
727cbfea AV	237	ret = schedule_timeout(
727cbfea AV	238	ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ);
1182fca3 MM	239
	240	gossip_debug(GOSSIP_WAIT_DEBUG,
	241	"Value returned from schedule_timeout:"
	242	"%d.\n",
	243	ret);
	244	gossip_debug(GOSSIP_WAIT_DEBUG,
	245	"Is shared memory available? (%d).\n",
7d221485	246	orangefs_get_bufmap_init());
1182fca3	247
ce6c414e	248	finish_wait(&orangefs_bufmap_init_waitq, &wait_entry);
1182fca3	249
7d221485	250	if (orangefs_get_bufmap_init() == 0) {
1182fca3 MM	251	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	252	__func__,
8bb8aefd	253	ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS,
1182fca3 MM	254	get_opname_string(op));
	255	return -EIO;
	256	}
	257
	258	/*
	259	* Return to the calling function and re-populate a
	260	* shared memory buffer.
	261	*/
	262	return -EAGAIN;
	263	}
	264	}
	265
	266	gossip_debug(GOSSIP_WAIT_DEBUG,
8bb8aefd	267	"orangefs: service_operation %s returning: %d for %p.\n",
1182fca3 MM	268	op_name,
	269	ret,
	270	op);
	271	return ret;
	272	}
	273
78699e29 AV	274	bool orangefs_cancel_op_in_progress(struct orangefs_kernel_op_s *op)
	275	{
	276	u64 tag = op->tag;
	277	if (!op_state_in_progress(op))
	278	return false;
	279
	280	op->slot_to_free = op->upcall.req.io.buf_index;
	281	memset(&op->upcall, 0, sizeof(op->upcall));
	282	memset(&op->downcall, 0, sizeof(op->downcall));
	283	op->upcall.type = ORANGEFS_VFS_OP_CANCEL;
	284	op->upcall.req.cancel.op_tag = tag;
	285	op->downcall.type = ORANGEFS_VFS_OP_INVALID;
	286	op->downcall.status = -1;
	287	orangefs_new_tag(op);
	288
	289	spin_lock(&orangefs_request_list_lock);
	290	/* orangefs_request_list_lock is enough of a barrier here */
	291	if (!__is_daemon_in_service()) {
	292	spin_unlock(&orangefs_request_list_lock);
	293	return false;
	294	}
	295	__add_op_to_request_list(op);
	296	spin_unlock(&orangefs_request_list_lock);
	297
	298	gossip_debug(GOSSIP_UTILS_DEBUG,
	299	"Attempting ORANGEFS operation cancellation of tag %llu\n",
	300	llu(tag));
	301	return true;
	302	}
	303
e07db0a2	304	static void orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op)
1182fca3 MM	305	{
	306	/*
	307	* handle interrupted cases depending on what state we were in when
	308	* the interruption is detected. there is a coarse grained lock
	309	* across the operation.
	310	*
eab9b389	311	* Called with op->lock held.
1182fca3	312	*/
ed42fe05	313	op->op_state \|= OP_VFS_STATE_GIVEN_UP;
1182fca3 MM	314
	315	if (op_state_waiting(op)) {
	316	/*
	317	* upcall hasn't been read; remove op from upcall request
	318	* list.
	319	*/
	320	spin_unlock(&op->lock);
ed42fe05 AV	321	spin_lock(&orangefs_request_list_lock);
	322	list_del(&op->list);
	323	spin_unlock(&orangefs_request_list_lock);
1182fca3 MM	324	gossip_debug(GOSSIP_WAIT_DEBUG,
	325	"Interrupted: Removed op %p from request_list\n",
	326	op);
	327	} else if (op_state_in_progress(op)) {
	328	/* op must be removed from the in progress htable */
	329	spin_unlock(&op->lock);
	330	spin_lock(&htable_ops_in_progress_lock);
	331	list_del(&op->list);
	332	spin_unlock(&htable_ops_in_progress_lock);
	333	gossip_debug(GOSSIP_WAIT_DEBUG,
	334	"Interrupted: Removed op %p"
	335	" from htable_ops_in_progress\n",
	336	op);
	337	} else if (!op_state_serviced(op)) {
	338	spin_unlock(&op->lock);
	339	gossip_err("interrupted operation is in a weird state 0x%x\n",
	340	op->op_state);
84d02150 MM	341	} else {
	342	/*
	343	* It is not intended for execution to flow here,
	344	* but having this unlock here makes sparse happy.
	345	*/
	346	gossip_err("%s: can't get here.\n", __func__);
	347	spin_unlock(&op->lock);
1182fca3	348	}
d2d87a3b	349	reinit_completion(&op->waitq);
1182fca3 MM	350	}
	351
	352	/*
	353	* sleeps on waitqueue waiting for matching downcall.
	354	* if client-core finishes servicing, then we are good to go.
	355	* else if client-core exits, we get woken up here, and retry with a timeout
	356	*
	357	* Post when this call returns to the caller, the specified op will no
	358	* longer be on any list or htable.
	359	*
	360	* Returns 0 on success and -errno on failure
	361	* Errors are:
	362	* EAGAIN in case we want the caller to requeue and try again..
	363	* EINTR/EIO/ETIMEDOUT indicating we are done trying to service this
	364	* operation since client-core seems to be exiting too often
	365	* or if we were interrupted.
d2d87a3b AV	366	*
d2d87a3b AV	367	* Returns with op->lock taken.
1182fca3	368	*/
b7ae37b0	369	static int wait_for_matching_downcall(struct orangefs_kernel_op_s *op)
1182fca3	370	{
d2d87a3b	371	long timeout, n;
1182fca3	372
d2d87a3b AV	373	timeout = op->attempts ? op_timeout_secs * HZ : MAX_SCHEDULE_TIMEOUT;
	374	n = wait_for_completion_interruptible_timeout(&op->waitq, timeout);
	375	spin_lock(&op->lock);
1182fca3	376
d2d87a3b AV	377	if (op_state_serviced(op))
d2d87a3b AV	378	return 0;
70c6ea26	379
d2d87a3b AV	380	if (unlikely(n < 0)) {
	381	gossip_debug(GOSSIP_WAIT_DEBUG,
	382	"*** %s:"
	383	" operation interrupted by a signal (tag "
	384	"%llu, op %p)\n",
	385	__func__,
	386	llu(op->tag),
	387	op);
	388	return -EINTR;
1182fca3	389	}
d2d87a3b AV	390	op->attempts++;
	391	if (op_state_purged(op)) {
	392	gossip_debug(GOSSIP_WAIT_DEBUG,
	393	"*** %s:"
	394	" operation purged (tag "
	395	"%llu, %p, att %d)\n",
	396	__func__,
	397	llu(op->tag),
	398	op,
	399	op->attempts);
	400	return (op->attempts < ORANGEFS_PURGE_RETRY_COUNT) ?
	401	-EAGAIN :
	402	-EIO;
	403	}
	404	/* must have timed out, then... */
	405	gossip_debug(GOSSIP_WAIT_DEBUG,
	406	"*** %s:"
	407	" operation timed out (tag"
	408	" %llu, %p, att %d)\n",
	409	__func__,
	410	llu(op->tag),
	411	op,
	412	op->attempts);
	413	return -ETIMEDOUT;
1182fca3	414	}