[PATCH char-misc-next v2 21/22] misc: mic: SCIF fence
From: Ashutosh Dixit
Date: Tue Sep 29 2015 - 20:51:16 EST
From: Sudeep Dutt <sudeep.dutt@xxxxxxxxx>
This patch implements the fence APIs required to synchronize
DMAs. SCIF provides an interface to return a "mark" for all DMAs
programmed at the instant the API was called. Users can then "wait" on
the mark provided previously by blocking inside the kernel. Upon
receipt of a DMA completion interrupt the waiting thread is woken
up. There is also an interface to signal DMA completion by polling for
a location to be updated via a "signal" cookie to avoid the interrupt
overhead in the mark/wait interface. SCIF allows programming fences on
both the local and the remote node for both the mark/wait or the fence
signal APIs.
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx>
Reviewed-by: Nikhil Rao <nikhil.rao@xxxxxxxxx>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@xxxxxxxxx>
Signed-off-by: Sudeep Dutt <sudeep.dutt@xxxxxxxxx>
---
drivers/misc/mic/scif/scif_fence.c | 771 +++++++++++++++++++++++++++++++++++++
1 file changed, 771 insertions(+)
create mode 100644 drivers/misc/mic/scif/scif_fence.c
diff --git a/drivers/misc/mic/scif/scif_fence.c b/drivers/misc/mic/scif/scif_fence.c
new file mode 100644
index 0000000..7f2c96f
--- /dev/null
+++ b/drivers/misc/mic/scif/scif_fence.c
@@ -0,0 +1,771 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * Intel SCIF driver.
+ *
+ */
+
+#include "scif_main.h"
+
+/**
+ * scif_recv_mark: Handle SCIF_MARK request
+ * @msg: Interrupt message
+ *
+ * The peer has requested a mark.
+ */
+void scif_recv_mark(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
+ int mark, err;
+
+ err = _scif_fence_mark(ep, &mark);
+ if (err)
+ msg->uop = SCIF_MARK_NACK;
+ else
+ msg->uop = SCIF_MARK_ACK;
+ msg->payload[0] = ep->remote_ep;
+ msg->payload[2] = mark;
+ scif_nodeqp_send(ep->remote_dev, msg);
+}
+
+/**
+ * scif_recv_mark_resp: Handle SCIF_MARK_(N)ACK messages.
+ * @msg: Interrupt message
+ *
+ * The peer has responded to a SCIF_MARK message.
+ */
+void scif_recv_mark_resp(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
+ struct scif_fence_info *fence_req =
+ (struct scif_fence_info *)msg->payload[1];
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ if (msg->uop == SCIF_MARK_ACK) {
+ fence_req->state = OP_COMPLETED;
+ fence_req->dma_mark = (int)msg->payload[2];
+ } else {
+ fence_req->state = OP_FAILED;
+ }
+ mutex_unlock(&ep->rma_info.rma_lock);
+ complete(&fence_req->comp);
+}
+
+/**
+ * scif_recv_wait: Handle SCIF_WAIT request
+ * @msg: Interrupt message
+ *
+ * The peer has requested waiting on a fence.
+ */
+void scif_recv_wait(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
+ struct scif_remote_fence_info *fence;
+
+ /*
+ * Allocate structure for remote fence information and
+ * send a NACK if the allocation failed. The peer will
+ * return ENOMEM upon receiving a NACK.
+ */
+ fence = kmalloc(sizeof(*fence), GFP_KERNEL);
+ if (!fence) {
+ msg->payload[0] = ep->remote_ep;
+ msg->uop = SCIF_WAIT_NACK;
+ scif_nodeqp_send(ep->remote_dev, msg);
+ return;
+ }
+
+ /* Prepare the fence request */
+ memcpy(&fence->msg, msg, sizeof(struct scifmsg));
+ INIT_LIST_HEAD(&fence->list);
+
+ /* Insert to the global remote fence request list */
+ mutex_lock(&scif_info.fencelock);
+ atomic_inc(&ep->rma_info.fence_refcount);
+ list_add_tail(&fence->list, &scif_info.fence);
+ mutex_unlock(&scif_info.fencelock);
+
+ schedule_work(&scif_info.misc_work);
+}
+
+/**
+ * scif_recv_wait_resp: Handle SCIF_WAIT_(N)ACK messages.
+ * @msg: Interrupt message
+ *
+ * The peer has responded to a SCIF_WAIT message.
+ */
+void scif_recv_wait_resp(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
+ struct scif_fence_info *fence_req =
+ (struct scif_fence_info *)msg->payload[1];
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ if (msg->uop == SCIF_WAIT_ACK)
+ fence_req->state = OP_COMPLETED;
+ else
+ fence_req->state = OP_FAILED;
+ mutex_unlock(&ep->rma_info.rma_lock);
+ complete(&fence_req->comp);
+}
+
+/**
+ * scif_recv_sig_local: Handle SCIF_SIG_LOCAL request
+ * @msg: Interrupt message
+ *
+ * The peer has requested a signal on a local offset.
+ */
+void scif_recv_sig_local(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
+ int err;
+
+ err = scif_prog_signal(ep, msg->payload[1], msg->payload[2],
+ SCIF_WINDOW_SELF);
+ if (err)
+ msg->uop = SCIF_SIG_NACK;
+ else
+ msg->uop = SCIF_SIG_ACK;
+ msg->payload[0] = ep->remote_ep;
+ scif_nodeqp_send(ep->remote_dev, msg);
+}
+
+/**
+ * scif_recv_sig_remote: Handle SCIF_SIGNAL_REMOTE request
+ * @msg: Interrupt message
+ *
+ * The peer has requested a signal on a remote offset.
+ */
+void scif_recv_sig_remote(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
+ int err;
+
+ err = scif_prog_signal(ep, msg->payload[1], msg->payload[2],
+ SCIF_WINDOW_PEER);
+ if (err)
+ msg->uop = SCIF_SIG_NACK;
+ else
+ msg->uop = SCIF_SIG_ACK;
+ msg->payload[0] = ep->remote_ep;
+ scif_nodeqp_send(ep->remote_dev, msg);
+}
+
+/**
+ * scif_recv_sig_resp: Handle SCIF_SIG_(N)ACK messages.
+ * @msg: Interrupt message
+ *
+ * The peer has responded to a signal request.
+ */
+void scif_recv_sig_resp(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
+ struct scif_fence_info *fence_req =
+ (struct scif_fence_info *)msg->payload[3];
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ if (msg->uop == SCIF_SIG_ACK)
+ fence_req->state = OP_COMPLETED;
+ else
+ fence_req->state = OP_FAILED;
+ mutex_unlock(&ep->rma_info.rma_lock);
+ complete(&fence_req->comp);
+}
+
+static inline void *scif_get_local_va(off_t off, struct scif_window *window)
+{
+ struct page **pages = window->pinned_pages->pages;
+ int page_nr = (off - window->offset) >> PAGE_SHIFT;
+ off_t page_off = off & ~PAGE_MASK;
+
+ return page_address(pages[page_nr]) + page_off;
+}
+
+static void scif_prog_signal_cb(void *arg)
+{
+ struct scif_status *status = arg;
+
+ dma_pool_free(status->ep->remote_dev->signal_pool, status,
+ status->src_dma_addr);
+}
+
+static int _scif_prog_signal(scif_epd_t epd, dma_addr_t dst, u64 val)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ struct dma_chan *chan = ep->rma_info.dma_chan;
+ struct dma_device *ddev = chan->device;
+ bool x100 = !is_dma_copy_aligned(chan->device, 1, 1, 1);
+ struct dma_async_tx_descriptor *tx;
+ struct scif_status *status = NULL;
+ dma_addr_t src;
+ dma_cookie_t cookie;
+ int err;
+
+ tx = ddev->device_prep_dma_memcpy(chan, 0, 0, 0, DMA_PREP_FENCE);
+ if (!tx) {
+ err = -ENOMEM;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto alloc_fail;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ err = (int)cookie;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto alloc_fail;
+ }
+ dma_async_issue_pending(chan);
+ if (x100) {
+ /*
+ * For X100 use the status descriptor to write the value to
+ * the destination.
+ */
+ tx = ddev->device_prep_dma_imm_data(chan, dst, val, 0);
+ } else {
+ status = dma_pool_alloc(ep->remote_dev->signal_pool, GFP_KERNEL,
+ &src);
+ if (!status) {
+ err = -ENOMEM;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto alloc_fail;
+ }
+ status->val = val;
+ status->src_dma_addr = src;
+ status->ep = ep;
+ src += offsetof(struct scif_status, val);
+ tx = ddev->device_prep_dma_memcpy(chan, dst, src, sizeof(val),
+ DMA_PREP_INTERRUPT);
+ }
+ if (!tx) {
+ err = -ENOMEM;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto dma_fail;
+ }
+ if (!x100) {
+ tx->callback = scif_prog_signal_cb;
+ tx->callback_param = status;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ err = -EIO;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto dma_fail;
+ }
+ dma_async_issue_pending(chan);
+ return 0;
+dma_fail:
+ if (!x100)
+ dma_pool_free(ep->remote_dev->signal_pool, status,
+ status->src_dma_addr);
+alloc_fail:
+ return err;
+}
+
+/*
+ * scif_prog_signal:
+ * @epd - Endpoint Descriptor
+ * @offset - registered address to write @val to
+ * @val - Value to be written at @offset
+ * @type - Type of the window.
+ *
+ * Arrange to write a value to the registered offset after ensuring that the
+ * offset provided is indeed valid.
+ */
+int scif_prog_signal(scif_epd_t epd, off_t offset, u64 val,
+ enum scif_window_type type)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ struct scif_window *window = NULL;
+ struct scif_rma_req req;
+ dma_addr_t dst_dma_addr;
+ int err;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ req.out_window = &window;
+ req.offset = offset;
+ req.nr_bytes = sizeof(u64);
+ req.prot = SCIF_PROT_WRITE;
+ req.type = SCIF_WINDOW_SINGLE;
+ if (type == SCIF_WINDOW_SELF)
+ req.head = &ep->rma_info.reg_list;
+ else
+ req.head = &ep->rma_info.remote_reg_list;
+ /* Does a valid window exist? */
+ err = scif_query_window(&req);
+ if (err) {
+ dev_err(scif_info.mdev.this_device,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ goto unlock_ret;
+ }
+
+ if (scif_is_mgmt_node() && scifdev_self(ep->remote_dev)) {
+ u64 *dst_virt;
+
+ if (type == SCIF_WINDOW_SELF)
+ dst_virt = scif_get_local_va(offset, window);
+ else
+ dst_virt =
+ scif_get_local_va(offset, (struct scif_window *)
+ window->peer_window);
+ *dst_virt = val;
+ } else {
+ dst_dma_addr = __scif_off_to_dma_addr(window, offset);
+ err = _scif_prog_signal(epd, dst_dma_addr, val);
+ }
+unlock_ret:
+ mutex_unlock(&ep->rma_info.rma_lock);
+ return err;
+}
+
+static int _scif_fence_wait(scif_epd_t epd, int mark)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ dma_cookie_t cookie = mark & ~SCIF_REMOTE_FENCE;
+ int err;
+
+ /* Wait for DMA callback in scif_fence_mark_cb(..) */
+ err = wait_event_interruptible_timeout(ep->rma_info.markwq,
+ dma_async_is_tx_complete(
+ ep->rma_info.dma_chan,
+ cookie, NULL, NULL) ==
+ DMA_COMPLETE,
+ SCIF_NODE_ALIVE_TIMEOUT);
+ if (!err)
+ err = -ETIMEDOUT;
+ else if (err > 0)
+ err = 0;
+ return err;
+}
+
+/**
+ * scif_rma_handle_remote_fences:
+ *
+ * This routine services remote fence requests.
+ */
+void scif_rma_handle_remote_fences(void)
+{
+ struct list_head *item, *tmp;
+ struct scif_remote_fence_info *fence;
+ struct scif_endpt *ep;
+ int mark, err;
+
+ might_sleep();
+ mutex_lock(&scif_info.fencelock);
+ list_for_each_safe(item, tmp, &scif_info.fence) {
+ fence = list_entry(item, struct scif_remote_fence_info,
+ list);
+ /* Remove fence from global list */
+ list_del(&fence->list);
+
+ /* Initiate the fence operation */
+ ep = (struct scif_endpt *)fence->msg.payload[0];
+ mark = fence->msg.payload[2];
+ err = _scif_fence_wait(ep, mark);
+ if (err)
+ fence->msg.uop = SCIF_WAIT_NACK;
+ else
+ fence->msg.uop = SCIF_WAIT_ACK;
+ fence->msg.payload[0] = ep->remote_ep;
+ scif_nodeqp_send(ep->remote_dev, &fence->msg);
+ kfree(fence);
+ if (!atomic_sub_return(1, &ep->rma_info.fence_refcount))
+ schedule_work(&scif_info.misc_work);
+ }
+ mutex_unlock(&scif_info.fencelock);
+}
+
+static int _scif_send_fence(scif_epd_t epd, int uop, int mark, int *out_mark)
+{
+ int err;
+ struct scifmsg msg;
+ struct scif_fence_info *fence_req;
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+
+ fence_req = kmalloc(sizeof(*fence_req), GFP_KERNEL);
+ if (!fence_req) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ fence_req->state = OP_IN_PROGRESS;
+ init_completion(&fence_req->comp);
+
+ msg.src = ep->port;
+ msg.uop = uop;
+ msg.payload[0] = ep->remote_ep;
+ msg.payload[1] = (u64)fence_req;
+ if (uop == SCIF_WAIT)
+ msg.payload[2] = mark;
+ spin_lock(&ep->lock);
+ if (ep->state == SCIFEP_CONNECTED)
+ err = scif_nodeqp_send(ep->remote_dev, &msg);
+ else
+ err = -ENOTCONN;
+ spin_unlock(&ep->lock);
+ if (err)
+ goto error_free;
+retry:
+ /* Wait for a SCIF_WAIT_(N)ACK message */
+ err = wait_for_completion_timeout(&fence_req->comp,
+ SCIF_NODE_ALIVE_TIMEOUT);
+ if (!err && scifdev_alive(ep))
+ goto retry;
+ if (!err)
+ err = -ENODEV;
+ if (err > 0)
+ err = 0;
+ mutex_lock(&ep->rma_info.rma_lock);
+ if (err < 0) {
+ if (fence_req->state == OP_IN_PROGRESS)
+ fence_req->state = OP_FAILED;
+ }
+ if (fence_req->state == OP_FAILED && !err)
+ err = -ENOMEM;
+ if (uop == SCIF_MARK && fence_req->state == OP_COMPLETED)
+ *out_mark = SCIF_REMOTE_FENCE | fence_req->dma_mark;
+ mutex_unlock(&ep->rma_info.rma_lock);
+error_free:
+ kfree(fence_req);
+error:
+ return err;
+}
+
+/**
+ * scif_send_fence_mark:
+ * @epd: end point descriptor.
+ * @out_mark: Output DMA mark reported by peer.
+ *
+ * Send a remote fence mark request.
+ */
+static int scif_send_fence_mark(scif_epd_t epd, int *out_mark)
+{
+ return _scif_send_fence(epd, SCIF_MARK, 0, out_mark);
+}
+
+/**
+ * scif_send_fence_wait:
+ * @epd: end point descriptor.
+ * @mark: DMA mark to wait for.
+ *
+ * Send a remote fence wait request.
+ */
+static int scif_send_fence_wait(scif_epd_t epd, int mark)
+{
+ return _scif_send_fence(epd, SCIF_WAIT, mark, NULL);
+}
+
+static int _scif_send_fence_signal_wait(struct scif_endpt *ep,
+ struct scif_fence_info *fence_req)
+{
+ int err;
+
+retry:
+ /* Wait for a SCIF_SIG_(N)ACK message */
+ err = wait_for_completion_timeout(&fence_req->comp,
+ SCIF_NODE_ALIVE_TIMEOUT);
+ if (!err && scifdev_alive(ep))
+ goto retry;
+ if (!err)
+ err = -ENODEV;
+ if (err > 0)
+ err = 0;
+ if (err < 0) {
+ mutex_lock(&ep->rma_info.rma_lock);
+ if (fence_req->state == OP_IN_PROGRESS)
+ fence_req->state = OP_FAILED;
+ mutex_unlock(&ep->rma_info.rma_lock);
+ }
+ if (fence_req->state == OP_FAILED && !err)
+ err = -ENXIO;
+ return err;
+}
+
+/**
+ * scif_send_fence_signal:
+ * @epd - endpoint descriptor
+ * @loff - local offset
+ * @lval - local value to write to loffset
+ * @roff - remote offset
+ * @rval - remote value to write to roffset
+ * @flags - flags
+ *
+ * Sends a remote fence signal request
+ */
+static int scif_send_fence_signal(scif_epd_t epd, off_t roff, u64 rval,
+ off_t loff, u64 lval, int flags)
+{
+ int err = 0;
+ struct scifmsg msg;
+ struct scif_fence_info *fence_req;
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+
+ fence_req = kmalloc(sizeof(*fence_req), GFP_KERNEL);
+ if (!fence_req) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ fence_req->state = OP_IN_PROGRESS;
+ init_completion(&fence_req->comp);
+ msg.src = ep->port;
+ if (flags & SCIF_SIGNAL_LOCAL) {
+ msg.uop = SCIF_SIG_LOCAL;
+ msg.payload[0] = ep->remote_ep;
+ msg.payload[1] = roff;
+ msg.payload[2] = rval;
+ msg.payload[3] = (u64)fence_req;
+ spin_lock(&ep->lock);
+ if (ep->state == SCIFEP_CONNECTED)
+ err = scif_nodeqp_send(ep->remote_dev, &msg);
+ else
+ err = -ENOTCONN;
+ spin_unlock(&ep->lock);
+ if (err)
+ goto error_free;
+ err = _scif_send_fence_signal_wait(ep, fence_req);
+ if (err)
+ goto error_free;
+ }
+ fence_req->state = OP_IN_PROGRESS;
+
+ if (flags & SCIF_SIGNAL_REMOTE) {
+ msg.uop = SCIF_SIG_REMOTE;
+ msg.payload[0] = ep->remote_ep;
+ msg.payload[1] = loff;
+ msg.payload[2] = lval;
+ msg.payload[3] = (u64)fence_req;
+ spin_lock(&ep->lock);
+ if (ep->state == SCIFEP_CONNECTED)
+ err = scif_nodeqp_send(ep->remote_dev, &msg);
+ else
+ err = -ENOTCONN;
+ spin_unlock(&ep->lock);
+ if (err)
+ goto error_free;
+ err = _scif_send_fence_signal_wait(ep, fence_req);
+ }
+error_free:
+ kfree(fence_req);
+error:
+ return err;
+}
+
+static void scif_fence_mark_cb(void *arg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)arg;
+
+ wake_up_interruptible(&ep->rma_info.markwq);
+ atomic_dec(&ep->rma_info.fence_refcount);
+}
+
+/*
+ * _scif_fence_mark:
+ *
+ * @epd - endpoint descriptor
+ * Set up a mark for this endpoint and return the value of the mark.
+ */
+int _scif_fence_mark(scif_epd_t epd, int *mark)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ struct dma_chan *chan = ep->rma_info.dma_chan;
+ struct dma_device *ddev = chan->device;
+ struct dma_async_tx_descriptor *tx;
+ dma_cookie_t cookie;
+ int err;
+
+ tx = ddev->device_prep_dma_memcpy(chan, 0, 0, 0, DMA_PREP_FENCE);
+ if (!tx) {
+ err = -ENOMEM;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ return err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ err = (int)cookie;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ return err;
+ }
+ dma_async_issue_pending(chan);
+ tx = ddev->device_prep_dma_interrupt(chan, DMA_PREP_INTERRUPT);
+ if (!tx) {
+ err = -ENOMEM;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ return err;
+ }
+ tx->callback = scif_fence_mark_cb;
+ tx->callback_param = ep;
+ *mark = cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ err = (int)cookie;
+ dev_err(&ep->remote_dev->sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ return err;
+ }
+ atomic_inc(&ep->rma_info.fence_refcount);
+ dma_async_issue_pending(chan);
+ return 0;
+}
+
+#define SCIF_LOOPB_MAGIC_MARK 0xdead
+
+int scif_fence_mark(scif_epd_t epd, int flags, int *mark)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ int err = 0;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI fence_mark: ep %p flags 0x%x mark 0x%x\n",
+ ep, flags, *mark);
+ err = scif_verify_epd(ep);
+ if (err)
+ return err;
+
+ /* Invalid flags? */
+ if (flags & ~(SCIF_FENCE_INIT_SELF | SCIF_FENCE_INIT_PEER))
+ return -EINVAL;
+
+ /* At least one of init self or peer RMA should be set */
+ if (!(flags & (SCIF_FENCE_INIT_SELF | SCIF_FENCE_INIT_PEER)))
+ return -EINVAL;
+
+ /* Exactly one of init self or peer RMA should be set but not both */
+ if ((flags & SCIF_FENCE_INIT_SELF) && (flags & SCIF_FENCE_INIT_PEER))
+ return -EINVAL;
+
+ /*
+ * Management node loopback does not need to use DMA.
+ * Return a valid mark to be symmetric.
+ */
+ if (scifdev_self(ep->remote_dev) && scif_is_mgmt_node()) {
+ *mark = SCIF_LOOPB_MAGIC_MARK;
+ return 0;
+ }
+
+ if (flags & SCIF_FENCE_INIT_SELF)
+ err = _scif_fence_mark(epd, mark);
+ else
+ err = scif_send_fence_mark(ep, mark);
+
+ if (err)
+ dev_err(scif_info.mdev.this_device,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI fence_mark: ep %p flags 0x%x mark 0x%x err %d\n",
+ ep, flags, *mark, err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_fence_mark);
+
+int scif_fence_wait(scif_epd_t epd, int mark)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ int err = 0;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI fence_wait: ep %p mark 0x%x\n",
+ ep, mark);
+ err = scif_verify_epd(ep);
+ if (err)
+ return err;
+ /*
+ * Management node loopback does not need to use DMA.
+ * The only valid mark provided is 0 so simply
+ * return success if the mark is valid.
+ */
+ if (scifdev_self(ep->remote_dev) && scif_is_mgmt_node()) {
+ if (mark == SCIF_LOOPB_MAGIC_MARK)
+ return 0;
+ else
+ return -EINVAL;
+ }
+ if (mark & SCIF_REMOTE_FENCE)
+ err = scif_send_fence_wait(epd, mark);
+ else
+ err = _scif_fence_wait(epd, mark);
+ if (err < 0)
+ dev_err(scif_info.mdev.this_device,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_fence_wait);
+
+int scif_fence_signal(scif_epd_t epd, off_t loff, u64 lval,
+ off_t roff, u64 rval, int flags)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ int err = 0;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI fence_signal: ep %p loff 0x%lx lval 0x%llx roff 0x%lx rval 0x%llx flags 0x%x\n",
+ ep, loff, lval, roff, rval, flags);
+ err = scif_verify_epd(ep);
+ if (err)
+ return err;
+
+ /* Invalid flags? */
+ if (flags & ~(SCIF_FENCE_INIT_SELF | SCIF_FENCE_INIT_PEER |
+ SCIF_SIGNAL_LOCAL | SCIF_SIGNAL_REMOTE))
+ return -EINVAL;
+
+ /* At least one of init self or peer RMA should be set */
+ if (!(flags & (SCIF_FENCE_INIT_SELF | SCIF_FENCE_INIT_PEER)))
+ return -EINVAL;
+
+ /* Exactly one of init self or peer RMA should be set but not both */
+ if ((flags & SCIF_FENCE_INIT_SELF) && (flags & SCIF_FENCE_INIT_PEER))
+ return -EINVAL;
+
+ /* At least one of SCIF_SIGNAL_LOCAL or SCIF_SIGNAL_REMOTE required */
+ if (!(flags & (SCIF_SIGNAL_LOCAL | SCIF_SIGNAL_REMOTE)))
+ return -EINVAL;
+
+ /* Only Dword offsets allowed */
+ if ((flags & SCIF_SIGNAL_LOCAL) && (loff & (sizeof(u32) - 1)))
+ return -EINVAL;
+
+ /* Only Dword aligned offsets allowed */
+ if ((flags & SCIF_SIGNAL_REMOTE) && (roff & (sizeof(u32) - 1)))
+ return -EINVAL;
+
+ if (flags & SCIF_FENCE_INIT_PEER) {
+ err = scif_send_fence_signal(epd, roff, rval, loff,
+ lval, flags);
+ } else {
+ /* Local Signal in Local RAS */
+ if (flags & SCIF_SIGNAL_LOCAL) {
+ err = scif_prog_signal(epd, loff, lval,
+ SCIF_WINDOW_SELF);
+ if (err)
+ goto error_ret;
+ }
+
+ /* Signal in Remote RAS */
+ if (flags & SCIF_SIGNAL_REMOTE)
+ err = scif_prog_signal(epd, roff,
+ rval, SCIF_WINDOW_PEER);
+ }
+error_ret:
+ if (err)
+ dev_err(scif_info.mdev.this_device,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_fence_signal);
--
2.0.0.rc3.2.g998f840
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