v4.19.13 snapshot.
diff --git a/fs/orangefs/waitqueue.c b/fs/orangefs/waitqueue.c
new file mode 100644
index 0000000..0729d26
--- /dev/null
+++ b/fs/orangefs/waitqueue.c
@@ -0,0 +1,371 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (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 *op,
+ long timeout,
+ bool interruptible)
+ __acquires(op->lock);
+static void orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op)
+ __releases(op->lock);
+
+/*
+ * 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, *tmp;
+
+ spin_lock(&orangefs_request_list_lock);
+ list_for_each_entry_safe(op, tmp, &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);
+ gossip_debug(GOSSIP_DEV_DEBUG,
+ "%s: op:%s: op_state:%d: process:%s:\n",
+ __func__,
+ get_opname_string(op),
+ op->op_state,
+ current->comm);
+ }
+ 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)
+{
+ long timeout = MAX_SCHEDULE_TIMEOUT;
+ 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,
+ "%s: %s op:%p: process:%s: pid:%d:\n",
+ __func__,
+ op_name,
+ op,
+ current->comm,
+ current->pid);
+
+ /*
+ * If ORANGEFS_OP_NO_MUTEX was set in flags, we need to avoid
+ * acquiring the request_mutex because we're servicing a
+ * high priority remount operation and the request_mutex is
+ * already taken.
+ */
+ if (!(flags & ORANGEFS_OP_NO_MUTEX)) {
+ if (flags & ORANGEFS_OP_INTERRUPTIBLE)
+ ret = mutex_lock_interruptible(&orangefs_request_mutex);
+ else
+ ret = mutex_lock_killable(&orangefs_request_mutex);
+ /*
+ * check to see if we were interrupted while waiting for
+ * mutex
+ */
+ if (ret < 0) {
+ op->downcall.status = ret;
+ gossip_debug(GOSSIP_WAIT_DEBUG,
+ "%s: service_operation interrupted.\n",
+ __func__);
+ return ret;
+ }
+ }
+
+ /* queue up the operation */
+ spin_lock(&orangefs_request_list_lock);
+ spin_lock(&op->lock);
+ set_op_state_waiting(op);
+ gossip_debug(GOSSIP_DEV_DEBUG,
+ "%s: op:%s: op_state:%d: process:%s:\n",
+ __func__,
+ get_opname_string(op),
+ op->op_state,
+ current->comm);
+ /* add high priority remount op to the front of the line. */
+ 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()) {
+ gossip_debug(GOSSIP_WAIT_DEBUG,
+ "%s:client core is NOT in service.\n",
+ __func__);
+ /*
+ * Don't wait for the userspace component to return if
+ * the filesystem is being umounted anyway.
+ */
+ if (op->upcall.type == ORANGEFS_VFS_OP_FS_UMOUNT)
+ timeout = 0;
+ else
+ timeout = op_timeout_secs * HZ;
+ }
+ spin_unlock(&orangefs_request_list_lock);
+
+ if (!(flags & ORANGEFS_OP_NO_MUTEX))
+ mutex_unlock(&orangefs_request_mutex);
+
+ ret = wait_for_matching_downcall(op, timeout,
+ flags & ORANGEFS_OP_INTERRUPTIBLE);
+
+ gossip_debug(GOSSIP_WAIT_DEBUG,
+ "%s: wait_for_matching_downcall returned %d for %p\n",
+ __func__,
+ ret,
+ op);
+
+ /* got matching downcall; make sure status is in errno format */
+ if (!ret) {
+ spin_unlock(&op->lock);
+ op->downcall.status =
+ orangefs_normalize_to_errno(op->downcall.status);
+ ret = op->downcall.status;
+ goto out;
+ }
+
+ /* failed to get matching downcall */
+ if (ret == -ETIMEDOUT) {
+ gossip_err("%s: %s -- wait timed out; aborting attempt.\n",
+ __func__,
+ op_name);
+ }
+
+ /*
+ * remove a waiting op from the request list or
+ * remove an in-progress op from the in-progress list.
+ */
+ orangefs_clean_up_interrupted_operation(op);
+
+ op->downcall.status = ret;
+ /* retry if operation has not been serviced and if requested */
+ if (ret == -EAGAIN) {
+ op->attempts++;
+ timeout = op_timeout_secs * HZ;
+ gossip_debug(GOSSIP_WAIT_DEBUG,
+ "orangefs: tag %llu (%s)"
+ " -- operation to be retried (%d attempt)\n",
+ llu(op->tag),
+ op_name,
+ op->attempts);
+
+ /*
+ * io ops (ops that use the shared memory buffer) have
+ * to be returned to their caller for a retry. Other ops
+ * can just be recycled here.
+ */
+ if (!op->uses_shared_memory)
+ goto retry_servicing;
+ }
+
+out:
+ gossip_debug(GOSSIP_WAIT_DEBUG,
+ "%s: %s returning: %d for %p.\n",
+ __func__,
+ op_name,
+ ret,
+ op);
+ return ret;
+}
+
+/* This can get called on an I/O op if it had a bad service_operation. */
+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);
+ gossip_debug(GOSSIP_DEV_DEBUG,
+ "%s: op:%s: op_state:%d: process:%s:\n",
+ __func__,
+ get_opname_string(op),
+ op->op_state,
+ current->comm);
+ list_add(&op->list, &orangefs_request_list);
+ spin_unlock(&op->lock);
+ spin_unlock(&orangefs_request_list_lock);
+
+ gossip_debug(GOSSIP_WAIT_DEBUG,
+ "Attempting ORANGEFS operation cancellation of tag %llu\n",
+ llu(tag));
+ return true;
+}
+
+/*
+ * Change an op to the "given up" state and remove it from its list.
+ */
+static void
+ orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op)
+ __releases(op->lock)
+{
+ /*
+ * handle interrupted cases depending on what state we were in when
+ * the interruption is detected.
+ *
+ * Called with op->lock held.
+ */
+
+ /*
+ * List manipulation code elsewhere will ignore ops that
+ * have been given up upon.
+ */
+ op->op_state |= OP_VFS_STATE_GIVEN_UP;
+
+ if (list_empty(&op->list)) {
+ /* caught copying to/from daemon */
+ BUG_ON(op_state_serviced(op));
+ spin_unlock(&op->lock);
+ wait_for_completion(&op->waitq);
+ } else 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_init(&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(&orangefs_htable_ops_in_progress_lock);
+ list_del_init(&op->list);
+ spin_unlock(&orangefs_htable_ops_in_progress_lock);
+ gossip_debug(GOSSIP_WAIT_DEBUG,
+ "Interrupted: Removed op %p"
+ " from htable_ops_in_progress\n",
+ op);
+ } else {
+ spin_unlock(&op->lock);
+ gossip_err("interrupted operation is in a weird state 0x%x\n",
+ op->op_state);
+ }
+ 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
+ *
+ * When this call returns to the caller, the specified op will no
+ * longer be in either the in_progress hash table or on the request list.
+ *
+ * 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,
+ bool interruptible)
+ __acquires(op->lock)
+{
+ long n;
+
+ /*
+ * There's a "schedule_timeout" inside of these wait
+ * primitives, during which the op is out of the hands of the
+ * user process that needs something done and is being
+ * manipulated by the client-core process.
+ */
+ if (interruptible)
+ n = wait_for_completion_interruptible_timeout(&op->waitq,
+ timeout);
+ else
+ n = wait_for_completion_killable_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, tag %llu, %p\n",
+ __func__,
+ llu(op->tag),
+ op);
+ return -EINTR;
+ }
+ if (op_state_purged(op)) {
+ gossip_debug(GOSSIP_WAIT_DEBUG,
+ "%s: operation purged, tag %llu, %p, %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, %d)\n",
+ __func__,
+ llu(op->tag),
+ op,
+ op->attempts);
+ return -ETIMEDOUT;
+}