From: Sudeep Dutt <sudeep.d...@intel.com> 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.di...@intel.com> Reviewed-by: Nikhil Rao <nikhil....@intel.com> Signed-off-by: Sudeep Dutt <sudeep.d...@intel.com> --- drivers/misc/mic/scif/scif_fence.c | 773 +++++++++++++++++++++++++++++++++++++ 1 file changed, 773 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..1620aaa --- /dev/null +++ b/drivers/misc/mic/scif/scif_fence.c @@ -0,0 +1,773 @@ +/* + * 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 (SCIF_MARK_ACK == msg->uop) { + 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 (SCIF_WAIT_ACK == msg->uop) + 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 (SCIF_SIG_ACK == msg->uop) + 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, flags = 0; + + if (x100) { + /* + * For X100 use the status descriptor to write the value to + * the destination. For this the value itself is passed as + * the source address into the DMA engine API + */ + src = val; + } 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); + flags = DMA_PREP_INTERRUPT; + } + + 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 dma_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 dma_fail; + } + dma_async_issue_pending(chan); + tx = ddev->device_prep_dma_memcpy(chan, dst, src, sizeof(val), flags); + 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(status->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 (SCIF_WINDOW_SELF == type) + 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 (SCIF_WINDOW_SELF == type) + 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 (SCIF_WAIT == uop) + msg.payload[2] = mark; + spin_lock(&ep->lock); + if (SCIFEP_CONNECTED == ep->state) + 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 (OP_IN_PROGRESS == fence_req->state) + fence_req->state = OP_FAILED; + } + if (OP_FAILED == fence_req->state && !err) + err = -ENOMEM; + if (SCIF_MARK == uop && OP_COMPLETED == fence_req->state) + *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 (OP_IN_PROGRESS == fence_req->state) + fence_req->state = OP_FAILED; + mutex_unlock(&ep->rma_info.rma_lock); + } + if (OP_FAILED == fence_req->state && !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 (SCIFEP_CONNECTED == ep->state) + 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 (SCIFEP_CONNECTED == ep->state) + 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 (SCIF_LOOPB_MAGIC_MARK == 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/