--- /dev/null
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2014 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 "../bus/scif_bus.h"
+#include "scif_peer_bus.h"
+#include "scif_main.h"
+#include "scif_nodeqp.h"
+#include "scif_map.h"
+
+/*
+ ************************************************************************
+ * SCIF node Queue Pair (QP) setup flow:
+ *
+ * 1) SCIF driver gets probed with a scif_hw_dev via the scif_hw_bus
+ * 2) scif_setup_qp(..) allocates the local qp and calls
+ * scif_setup_qp_connect(..) which allocates and maps the local
+ * buffer for the inbound QP
+ * 3) The local node updates the device page with the DMA address of the QP
+ * 4) A delayed work is scheduled (qp_dwork) which periodically reads if
+ * the peer node has updated its QP DMA address
+ * 5) Once a valid non zero address is found in the QP DMA address field
+ * in the device page, the local node maps the remote node's QP,
+ * updates its outbound QP and sends a SCIF_INIT message to the peer
+ * 6) The SCIF_INIT message is received by the peer node QP interrupt bottom
+ * half handler by calling scif_init(..)
+ * 7) scif_init(..) registers a new SCIF peer node by calling
+ * scif_peer_register_device(..) which signifies the addition of a new
+ * SCIF node
+ * 8) On the mgmt node, P2P network setup/teardown is initiated if all the
+ * remote nodes are online via scif_p2p_setup(..)
+ * 9) For P2P setup, the host maps the remote nodes' aperture and memory
+ * bars and sends a SCIF_NODE_ADD message to both nodes
+ * 10) As part of scif_nodeadd, both nodes set up their local inbound
+ * QPs and send a SCIF_NODE_ADD_ACK to the mgmt node
+ * 11) As part of scif_node_add_ack(..) the mgmt node forwards the
+ * SCIF_NODE_ADD_ACK to the remote nodes
+ * 12) As part of scif_node_add_ack(..) the remote nodes update their
+ * outbound QPs, make sure they can access memory on the remote node
+ * and then add a new SCIF peer node by calling
+ * scif_peer_register_device(..) which signifies the addition of a new
+ * SCIF node.
+ * 13) The SCIF network is now established across all nodes.
+ *
+ ************************************************************************
+ * SCIF node QP teardown flow (initiated by non mgmt node):
+ *
+ * 1) SCIF driver gets a remove callback with a scif_hw_dev via the scif_hw_bus
+ * 2) The device page QP DMA address field is updated with 0x0
+ * 3) A non mgmt node now cleans up all local data structures and sends a
+ * SCIF_EXIT message to the peer and waits for a SCIF_EXIT_ACK
+ * 4) As part of scif_exit(..) handling scif_disconnect_node(..) is called
+ * 5) scif_disconnect_node(..) sends a SCIF_NODE_REMOVE message to all the
+ * peers and waits for a SCIF_NODE_REMOVE_ACK
+ * 6) As part of scif_node_remove(..) a remote node unregisters the peer
+ * node from the SCIF network and sends a SCIF_NODE_REMOVE_ACK
+ * 7) When the mgmt node has received all the SCIF_NODE_REMOVE_ACKs
+ * it sends itself a node remove message whose handling cleans up local
+ * data structures and unregisters the peer node from the SCIF network
+ * 8) The mgmt node sends a SCIF_EXIT_ACK
+ * 9) Upon receipt of the SCIF_EXIT_ACK the node initiating the teardown
+ * completes the SCIF remove routine
+ * 10) The SCIF network is now torn down for the node initiating the
+ * teardown sequence
+ *
+ ************************************************************************
+ * SCIF node QP teardown flow (initiated by mgmt node):
+ *
+ * 1) SCIF driver gets a remove callback with a scif_hw_dev via the scif_hw_bus
+ * 2) The device page QP DMA address field is updated with 0x0
+ * 3) The mgmt node calls scif_disconnect_node(..)
+ * 4) scif_disconnect_node(..) sends a SCIF_NODE_REMOVE message to all the peers
+ * and waits for a SCIF_NODE_REMOVE_ACK
+ * 5) As part of scif_node_remove(..) a remote node unregisters the peer
+ * node from the SCIF network and sends a SCIF_NODE_REMOVE_ACK
+ * 6) When the mgmt node has received all the SCIF_NODE_REMOVE_ACKs
+ * it unregisters the peer node from the SCIF network
+ * 7) The mgmt node sends a SCIF_EXIT message and waits for a SCIF_EXIT_ACK.
+ * 8) A non mgmt node upon receipt of a SCIF_EXIT message calls scif_stop(..)
+ * which would clean up local data structures for all SCIF nodes and
+ * then send a SCIF_EXIT_ACK back to the mgmt node
+ * 9) Upon receipt of the SCIF_EXIT_ACK the the mgmt node sends itself a node
+ * remove message whose handling cleans up local data structures and
+ * destroys any P2P mappings.
+ * 10) The SCIF hardware device for which a remove callback was received is now
+ * disconnected from the SCIF network.
+ */
+/*
+ * Initializes "local" data structures for the QP. Allocates the QP
+ * ring buffer (rb) and initializes the "in bound" queue.
+ */
+int scif_setup_qp_connect(struct scif_qp *qp, dma_addr_t *qp_offset,
+ int local_size, struct scif_dev *scifdev)
+{
+ void *local_q = NULL;
+ int err = 0;
+ u32 tmp_rd = 0;
+
+ spin_lock_init(&qp->send_lock);
+ spin_lock_init(&qp->recv_lock);
+
+ local_q = kzalloc(local_size, GFP_KERNEL);
+ if (!local_q) {
+ err = -ENOMEM;
+ return err;
+ }
+ err = scif_map_single(&qp->local_buf, local_q, scifdev, local_size);
+ if (err)
+ goto kfree;
+ /*
+ * To setup the inbound_q, the buffer lives locally, the read pointer
+ * is remote and the write pointer is local.
+ */
+ scif_rb_init(&qp->inbound_q,
+ &tmp_rd,
+ &qp->local_write,
+ local_q, get_count_order(local_size));
+ /*
+ * The read pointer is NULL initially and it is unsafe to use the ring
+ * buffer til this changes!
+ */
+ qp->inbound_q.read_ptr = NULL;
+ err = scif_map_single(qp_offset, qp,
+ scifdev, sizeof(struct scif_qp));
+ if (err)
+ goto unmap;
+ qp->local_qp = *qp_offset;
+ return err;
+unmap:
+ scif_unmap_single(qp->local_buf, scifdev, local_size);
+ qp->local_buf = 0;
+kfree:
+ kfree(local_q);
+ return err;
+}
+
+/* When the other side has already done it's allocation, this is called */
+int scif_setup_qp_accept(struct scif_qp *qp, dma_addr_t *qp_offset,
+ dma_addr_t phys, int local_size,
+ struct scif_dev *scifdev)
+{
+ void *local_q;
+ void *remote_q;
+ struct scif_qp *remote_qp;
+ int remote_size;
+ int err = 0;
+
+ spin_lock_init(&qp->send_lock);
+ spin_lock_init(&qp->recv_lock);
+ /* Start by figuring out where we need to point */
+ remote_qp = scif_ioremap(phys, sizeof(struct scif_qp), scifdev);
+ if (!remote_qp)
+ return -EIO;
+ qp->remote_qp = remote_qp;
+ if (qp->remote_qp->magic != SCIFEP_MAGIC) {
+ err = -EIO;
+ goto iounmap;
+ }
+ qp->remote_buf = remote_qp->local_buf;
+ remote_size = qp->remote_qp->inbound_q.size;
+ remote_q = scif_ioremap(qp->remote_buf, remote_size, scifdev);
+ if (!remote_q) {
+ err = -EIO;
+ goto iounmap;
+ }
+ qp->remote_qp->local_write = 0;
+ /*
+ * To setup the outbound_q, the buffer lives in remote memory,
+ * the read pointer is local, the write pointer is remote
+ */
+ scif_rb_init(&qp->outbound_q,
+ &qp->local_read,
+ &qp->remote_qp->local_write,
+ remote_q,
+ get_count_order(remote_size));
+ local_q = kzalloc(local_size, GFP_KERNEL);
+ if (!local_q) {
+ err = -ENOMEM;
+ goto iounmap_1;
+ }
+ err = scif_map_single(&qp->local_buf, local_q, scifdev, local_size);
+ if (err)
+ goto kfree;
+ qp->remote_qp->local_read = 0;
+ /*
+ * To setup the inbound_q, the buffer lives locally, the read pointer
+ * is remote and the write pointer is local
+ */
+ scif_rb_init(&qp->inbound_q,
+ &qp->remote_qp->local_read,
+ &qp->local_write,
+ local_q, get_count_order(local_size));
+ err = scif_map_single(qp_offset, qp, scifdev,
+ sizeof(struct scif_qp));
+ if (err)
+ goto unmap;
+ qp->local_qp = *qp_offset;
+ return err;
+unmap:
+ scif_unmap_single(qp->local_buf, scifdev, local_size);
+ qp->local_buf = 0;
+kfree:
+ kfree(local_q);
+iounmap_1:
+ scif_iounmap(remote_q, remote_size, scifdev);
+ qp->outbound_q.rb_base = NULL;
+iounmap:
+ scif_iounmap(qp->remote_qp, sizeof(struct scif_qp), scifdev);
+ qp->remote_qp = NULL;
+ return err;
+}
+
+int scif_setup_qp_connect_response(struct scif_dev *scifdev,
+ struct scif_qp *qp, u64 payload)
+{
+ int err = 0;
+ void *r_buf;
+ int remote_size;
+ phys_addr_t tmp_phys;
+
+ qp->remote_qp = scif_ioremap(payload, sizeof(struct scif_qp), scifdev);
+
+ if (!qp->remote_qp) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ if (qp->remote_qp->magic != SCIFEP_MAGIC) {
+ dev_err(&scifdev->sdev->dev,
+ "SCIFEP_MAGIC mismatch between self %d remote %d\n",
+ scif_dev[scif_info.nodeid].node, scifdev->node);
+ err = -ENODEV;
+ goto error;
+ }
+
+ tmp_phys = qp->remote_qp->local_buf;
+ remote_size = qp->remote_qp->inbound_q.size;
+ r_buf = scif_ioremap(tmp_phys, remote_size, scifdev);
+
+ if (!r_buf)
+ return -EIO;
+
+ qp->local_read = 0;
+ scif_rb_init(&qp->outbound_q,
+ &qp->local_read,
+ &qp->remote_qp->local_write,
+ r_buf,
+ get_count_order(remote_size));
+ /*
+ * resetup the inbound_q now that we know where the
+ * inbound_read really is.
+ */
+ scif_rb_init(&qp->inbound_q,
+ &qp->remote_qp->local_read,
+ &qp->local_write,
+ qp->inbound_q.rb_base,
+ get_count_order(qp->inbound_q.size));
+error:
+ return err;
+}
+
+static __always_inline void
+scif_send_msg_intr(struct scif_dev *scifdev)
+{
+ struct scif_hw_dev *sdev = scifdev->sdev;
+
+ if (scifdev_is_p2p(scifdev))
+ sdev->hw_ops->send_p2p_intr(sdev, scifdev->rdb, &scifdev->mmio);
+ else
+ sdev->hw_ops->send_intr(sdev, scifdev->rdb);
+}
+
+int scif_qp_response(phys_addr_t phys, struct scif_dev *scifdev)
+{
+ int err = 0;
+ struct scifmsg msg;
+
+ err = scif_setup_qp_connect_response(scifdev, scifdev->qpairs, phys);
+ if (!err) {
+ /*
+ * Now that everything is setup and mapped, we're ready
+ * to tell the peer about our queue's location
+ */
+ msg.uop = SCIF_INIT;
+ msg.dst.node = scifdev->node;
+ err = scif_nodeqp_send(scifdev, &msg);
+ }
+ return err;
+}
+
+void scif_send_exit(struct scif_dev *scifdev)
+{
+ struct scifmsg msg;
+ int ret;
+
+ scifdev->exit = OP_IN_PROGRESS;
+ msg.uop = SCIF_EXIT;
+ msg.src.node = scif_info.nodeid;
+ msg.dst.node = scifdev->node;
+ ret = scif_nodeqp_send(scifdev, &msg);
+ if (ret)
+ goto done;
+ /* Wait for a SCIF_EXIT_ACK message */
+ wait_event_timeout(scif_info.exitwq, scifdev->exit == OP_COMPLETED,
+ SCIF_NODE_ALIVE_TIMEOUT);
+done:
+ scifdev->exit = OP_IDLE;
+}
+
+int scif_setup_qp(struct scif_dev *scifdev)
+{
+ int err = 0;
+ int local_size;
+ struct scif_qp *qp;
+
+ local_size = SCIF_NODE_QP_SIZE;
+
+ qp = kzalloc(sizeof(*qp), GFP_KERNEL);
+ if (!qp) {
+ err = -ENOMEM;
+ return err;
+ }
+ qp->magic = SCIFEP_MAGIC;
+ scifdev->qpairs = qp;
+ err = scif_setup_qp_connect(qp, &scifdev->qp_dma_addr,
+ local_size, scifdev);
+ if (err)
+ goto free_qp;
+ /*
+ * We're as setup as we can be. The inbound_q is setup, w/o a usable
+ * outbound q. When we get a message, the read_ptr will be updated,
+ * and we will pull the message.
+ */
+ return err;
+free_qp:
+ kfree(scifdev->qpairs);
+ scifdev->qpairs = NULL;
+ return err;
+}
+
+static void scif_p2p_freesg(struct scatterlist *sg)
+{
+ kfree(sg);
+}
+
+static struct scatterlist *
+scif_p2p_setsg(void __iomem *va, int page_size, int page_cnt)
+{
+ struct scatterlist *sg;
+ struct page *page;
+ int i;
+
+ sg = kcalloc(page_cnt, sizeof(struct scatterlist), GFP_KERNEL);
+ if (!sg)
+ return NULL;
+ sg_init_table(sg, page_cnt);
+ for (i = 0; i < page_cnt; i++) {
+ page = vmalloc_to_page((void __force *)va);
+ if (!page)
+ goto p2p_sg_err;
+ sg_set_page(&sg[i], page, page_size, 0);
+ va += page_size;
+ }
+ return sg;
+p2p_sg_err:
+ kfree(sg);
+ return NULL;
+}
+
+/* Init p2p mappings required to access peerdev from scifdev */
+static struct scif_p2p_info *
+scif_init_p2p_info(struct scif_dev *scifdev, struct scif_dev *peerdev)
+{
+ struct scif_p2p_info *p2p;
+ int num_mmio_pages, num_aper_pages, sg_page_shift, err, num_aper_chunks;
+ struct scif_hw_dev *psdev = peerdev->sdev;
+ struct scif_hw_dev *sdev = scifdev->sdev;
+
+ num_mmio_pages = psdev->mmio->len >> PAGE_SHIFT;
+ num_aper_pages = psdev->aper->len >> PAGE_SHIFT;
+
+ p2p = kzalloc(sizeof(*p2p), GFP_KERNEL);
+ if (!p2p)
+ return NULL;
+ p2p->ppi_sg[SCIF_PPI_MMIO] = scif_p2p_setsg(psdev->mmio->va,
+ PAGE_SIZE, num_mmio_pages);
+ if (!p2p->ppi_sg[SCIF_PPI_MMIO])
+ goto free_p2p;
+ p2p->sg_nentries[SCIF_PPI_MMIO] = num_mmio_pages;
+ sg_page_shift = get_order(min(psdev->aper->len, (u64)(1 << 30)));
+ num_aper_chunks = num_aper_pages >> (sg_page_shift - PAGE_SHIFT);
+ p2p->ppi_sg[SCIF_PPI_APER] = scif_p2p_setsg(psdev->aper->va,
+ 1 << sg_page_shift,
+ num_aper_chunks);
+ p2p->sg_nentries[SCIF_PPI_APER] = num_aper_chunks;
+ err = dma_map_sg(&sdev->dev, p2p->ppi_sg[SCIF_PPI_MMIO],
+ num_mmio_pages, PCI_DMA_BIDIRECTIONAL);
+ if (err != num_mmio_pages)
+ goto scif_p2p_free;
+ err = dma_map_sg(&sdev->dev, p2p->ppi_sg[SCIF_PPI_APER],
+ num_aper_chunks, PCI_DMA_BIDIRECTIONAL);
+ if (err != num_aper_chunks)
+ goto dma_unmap;
+ p2p->ppi_da[SCIF_PPI_MMIO] = sg_dma_address(p2p->ppi_sg[SCIF_PPI_MMIO]);
+ p2p->ppi_da[SCIF_PPI_APER] = sg_dma_address(p2p->ppi_sg[SCIF_PPI_APER]);
+ p2p->ppi_len[SCIF_PPI_MMIO] = num_mmio_pages;
+ p2p->ppi_len[SCIF_PPI_APER] = num_aper_pages;
+ p2p->ppi_peer_id = peerdev->node;
+ return p2p;
+dma_unmap:
+ dma_unmap_sg(&sdev->dev, p2p->ppi_sg[SCIF_PPI_MMIO],
+ p2p->sg_nentries[SCIF_PPI_MMIO], DMA_BIDIRECTIONAL);
+scif_p2p_free:
+ scif_p2p_freesg(p2p->ppi_sg[SCIF_PPI_MMIO]);
+ scif_p2p_freesg(p2p->ppi_sg[SCIF_PPI_APER]);
+free_p2p:
+ kfree(p2p);
+ return NULL;
+}
+
+/**
+ * scif_node_connect: Respond to SCIF_NODE_CONNECT interrupt message
+ * @dst: Destination node
+ *
+ * Connect the src and dst node by setting up the p2p connection
+ * between them. Management node here acts like a proxy.
+ */
+static void scif_node_connect(struct scif_dev *scifdev, int dst)
+{
+ struct scif_dev *dev_j = scifdev;
+ struct scif_dev *dev_i = NULL;
+ struct scif_p2p_info *p2p_ij = NULL; /* bus addr for j from i */
+ struct scif_p2p_info *p2p_ji = NULL; /* bus addr for i from j */
+ struct scif_p2p_info *p2p;
+ struct list_head *pos, *tmp;
+ struct scifmsg msg;
+ int err;
+ u64 tmppayload;
+
+ if (dst < 1 || dst > scif_info.maxid)
+ return;
+
+ dev_i = &scif_dev[dst];
+
+ if (!_scifdev_alive(dev_i))
+ return;
+ /*
+ * If the p2p connection is already setup or in the process of setting
+ * up then just ignore this request. The requested node will get
+ * informed by SCIF_NODE_ADD_ACK or SCIF_NODE_ADD_NACK
+ */
+ if (!list_empty(&dev_i->p2p)) {
+ list_for_each_safe(pos, tmp, &dev_i->p2p) {
+ p2p = list_entry(pos, struct scif_p2p_info, ppi_list);
+ if (p2p->ppi_peer_id == dev_j->node)
+ return;
+ }
+ }
+ p2p_ij = scif_init_p2p_info(dev_i, dev_j);
+ if (!p2p_ij)
+ return;
+ p2p_ji = scif_init_p2p_info(dev_j, dev_i);
+ if (!p2p_ji)
+ return;
+ list_add_tail(&p2p_ij->ppi_list, &dev_i->p2p);
+ list_add_tail(&p2p_ji->ppi_list, &dev_j->p2p);
+
+ /*
+ * Send a SCIF_NODE_ADD to dev_i, pass it its bus address
+ * as seen from dev_j
+ */
+ msg.uop = SCIF_NODE_ADD;
+ msg.src.node = dev_j->node;
+ msg.dst.node = dev_i->node;
+
+ msg.payload[0] = p2p_ji->ppi_da[SCIF_PPI_APER];
+ msg.payload[1] = p2p_ij->ppi_da[SCIF_PPI_MMIO];
+ msg.payload[2] = p2p_ij->ppi_da[SCIF_PPI_APER];
+ msg.payload[3] = p2p_ij->ppi_len[SCIF_PPI_APER] << PAGE_SHIFT;
+
+ err = scif_nodeqp_send(dev_i, &msg);
+ if (err) {
+ dev_err(&scifdev->sdev->dev,
+ "%s %d error %d\n", __func__, __LINE__, err);
+ return;
+ }
+
+ /* Same as above but to dev_j */
+ msg.uop = SCIF_NODE_ADD;
+ msg.src.node = dev_i->node;
+ msg.dst.node = dev_j->node;
+
+ tmppayload = msg.payload[0];
+ msg.payload[0] = msg.payload[2];
+ msg.payload[2] = tmppayload;
+ msg.payload[1] = p2p_ji->ppi_da[SCIF_PPI_MMIO];
+ msg.payload[3] = p2p_ji->ppi_len[SCIF_PPI_APER] << PAGE_SHIFT;
+
+ scif_nodeqp_send(dev_j, &msg);
+}
+
+static void scif_p2p_setup(void)
+{
+ int i, j;
+
+ if (!scif_info.p2p_enable)
+ return;
+
+ for (i = 1; i <= scif_info.maxid; i++)
+ if (!_scifdev_alive(&scif_dev[i]))
+ return;
+
+ for (i = 1; i <= scif_info.maxid; i++) {
+ for (j = 1; j <= scif_info.maxid; j++) {
+ struct scif_dev *scifdev = &scif_dev[i];
+
+ if (i == j)
+ continue;
+ scif_node_connect(scifdev, j);
+ }
+ }
+}
+
+void scif_qp_response_ack(struct work_struct *work)
+{
+ struct scif_dev *scifdev = container_of(work, struct scif_dev,
+ init_msg_work);
+ struct scif_peer_dev *spdev;
+
+ /* Drop the INIT message if it has already been received */
+ if (_scifdev_alive(scifdev))
+ return;
+
+ spdev = scif_peer_register_device(scifdev);
+ if (IS_ERR(spdev))
+ return;
+
+ if (scif_is_mgmt_node()) {
+ mutex_lock(&scif_info.conflock);
+ scif_p2p_setup();
+ mutex_unlock(&scif_info.conflock);
+ }
+}
+
+static char *message_types[] = {"BAD",
+ "INIT",
+ "EXIT",
+ "SCIF_EXIT_ACK",
+ "SCIF_NODE_ADD",
+ "SCIF_NODE_ADD_ACK",
+ "SCIF_NODE_ADD_NACK",
+ "REMOVE_NODE",
+ "REMOVE_NODE_ACK"};
+
+static void
+scif_display_message(struct scif_dev *scifdev, struct scifmsg *msg,
+ const char *label)
+{
+ if (!scif_info.en_msg_log)
+ return;
+ if (msg->uop > SCIF_MAX_MSG) {
+ dev_err(&scifdev->sdev->dev,
+ "%s: unknown msg type %d\n", label, msg->uop);
+ return;
+ }
+ dev_info(&scifdev->sdev->dev,
+ "%s: msg type %s, src %d:%d, dest %d:%d payload 0x%llx:0x%llx:0x%llx:0x%llx\n",
+ label, message_types[msg->uop], msg->src.node, msg->src.port,
+ msg->dst.node, msg->dst.port, msg->payload[0], msg->payload[1],
+ msg->payload[2], msg->payload[3]);
+}
+
+int _scif_nodeqp_send(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_qp *qp = scifdev->qpairs;
+ int err = -ENOMEM, loop_cnt = 0;
+
+ scif_display_message(scifdev, msg, "Sent");
+ if (!qp) {
+ err = -EINVAL;
+ goto error;
+ }
+ spin_lock(&qp->send_lock);
+
+ while ((err = scif_rb_write(&qp->outbound_q,
+ msg, sizeof(struct scifmsg)))) {
+ mdelay(1);
+#define SCIF_NODEQP_SEND_TO_MSEC (3 * 1000)
+ if (loop_cnt++ > (SCIF_NODEQP_SEND_TO_MSEC)) {
+ err = -ENODEV;
+ break;
+ }
+ }
+ if (!err)
+ scif_rb_commit(&qp->outbound_q);
+ spin_unlock(&qp->send_lock);
+ if (!err) {
+ if (scifdev_self(scifdev))
+ /*
+ * For loopback we need to emulate an interrupt by
+ * queuing work for the queue handling real node
+ * Qp interrupts.
+ */
+ queue_work(scifdev->intr_wq, &scifdev->intr_bh);
+ else
+ scif_send_msg_intr(scifdev);
+ }
+error:
+ if (err)
+ dev_dbg(&scifdev->sdev->dev,
+ "%s %d error %d uop %d\n",
+ __func__, __LINE__, err, msg->uop);
+ return err;
+}
+
+/**
+ * scif_nodeqp_send - Send a message on the node queue pair
+ * @scifdev: Scif Device.
+ * @msg: The message to be sent.
+ */
+int scif_nodeqp_send(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ int err;
+ struct device *spdev = NULL;
+
+ if (msg->uop > SCIF_EXIT_ACK) {
+ /* Dont send messages once the exit flow has begun */
+ if (OP_IDLE != scifdev->exit)
+ return -ENODEV;
+ spdev = scif_get_peer_dev(scifdev);
+ if (IS_ERR(spdev)) {
+ err = PTR_ERR(spdev);
+ return err;
+ }
+ }
+ err = _scif_nodeqp_send(scifdev, msg);
+ if (msg->uop > SCIF_EXIT_ACK)
+ scif_put_peer_dev(spdev);
+ return err;
+}
+
+/*
+ * scif_misc_handler:
+ *
+ * Work queue handler for servicing miscellaneous SCIF tasks.
+ * Examples include:
+ * 1) Cleanup of zombie endpoints.
+ */
+void scif_misc_handler(struct work_struct *work)
+{
+ scif_cleanup_zombie_epd();
+}
+
+/**
+ * scif_init() - Respond to SCIF_INIT interrupt message
+ * @scifdev: Remote SCIF device node
+ * @msg: Interrupt message
+ */
+static __always_inline void
+scif_init(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ /*
+ * Allow the thread waiting for device page updates for the peer QP DMA
+ * address to complete initializing the inbound_q.
+ */
+ flush_delayed_work(&scifdev->qp_dwork);
+ /*
+ * Delegate the peer device registration to a workqueue, otherwise if
+ * SCIF client probe (called during peer device registration) calls
+ * scif_connect(..), it will block the message processing thread causing
+ * a deadlock.
+ */
+ schedule_work(&scifdev->init_msg_work);
+}
+
+/**
+ * scif_exit() - Respond to SCIF_EXIT interrupt message
+ * @scifdev: Remote SCIF device node
+ * @msg: Interrupt message
+ *
+ * This function stops the SCIF interface for the node which sent
+ * the SCIF_EXIT message and starts waiting for that node to
+ * resetup the queue pair again.
+ */
+static __always_inline void
+scif_exit(struct scif_dev *scifdev, struct scifmsg *unused)
+{
+ scifdev->exit_ack_pending = true;
+ if (scif_is_mgmt_node())
+ scif_disconnect_node(scifdev->node, false);
+ else
+ scif_stop(scifdev);
+ schedule_delayed_work(&scifdev->qp_dwork,
+ msecs_to_jiffies(1000));
+}
+
+/**
+ * scif_exitack() - Respond to SCIF_EXIT_ACK interrupt message
+ * @scifdev: Remote SCIF device node
+ * @msg: Interrupt message
+ *
+ */
+static __always_inline void
+scif_exit_ack(struct scif_dev *scifdev, struct scifmsg *unused)
+{
+ scifdev->exit = OP_COMPLETED;
+ wake_up(&scif_info.exitwq);
+}
+
+/**
+ * scif_node_add() - Respond to SCIF_NODE_ADD interrupt message
+ * @scifdev: Remote SCIF device node
+ * @msg: Interrupt message
+ *
+ * When the mgmt node driver has finished initializing a MIC node queue pair it
+ * marks the node as online. It then looks for all currently online MIC cards
+ * and send a SCIF_NODE_ADD message to identify the ID of the new card for
+ * peer to peer initialization
+ *
+ * The local node allocates its incoming queue and sends its address in the
+ * SCIF_NODE_ADD_ACK message back to the mgmt node, the mgmt node "reflects"
+ * this message to the new node
+ */
+static __always_inline void
+scif_node_add(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_dev *newdev;
+ dma_addr_t qp_offset;
+ int qp_connect;
+ struct scif_hw_dev *sdev;
+
+ dev_dbg(&scifdev->sdev->dev,
+ "Scifdev %d:%d received NODE_ADD msg for node %d\n",
+ scifdev->node, msg->dst.node, msg->src.node);
+ dev_dbg(&scifdev->sdev->dev,
+ "Remote address for this node's aperture %llx\n",
+ msg->payload[0]);
+ newdev = &scif_dev[msg->src.node];
+ newdev->node = msg->src.node;
+ newdev->sdev = scif_dev[SCIF_MGMT_NODE].sdev;
+ sdev = newdev->sdev;
+
+ if (scif_setup_intr_wq(newdev)) {
+ dev_err(&scifdev->sdev->dev,
+ "failed to setup interrupts for %d\n", msg->src.node);
+ goto interrupt_setup_error;
+ }
+ newdev->mmio.va = ioremap_nocache(msg->payload[1], sdev->mmio->len);
+ if (!newdev->mmio.va) {
+ dev_err(&scifdev->sdev->dev,
+ "failed to map mmio for %d\n", msg->src.node);
+ goto mmio_map_error;
+ }
+ newdev->qpairs = kzalloc(sizeof(*newdev->qpairs), GFP_KERNEL);
+ if (!newdev->qpairs)
+ goto qp_alloc_error;
+ /*
+ * Set the base address of the remote node's memory since it gets
+ * added to qp_offset
+ */
+ newdev->base_addr = msg->payload[0];
+
+ qp_connect = scif_setup_qp_connect(newdev->qpairs, &qp_offset,
+ SCIF_NODE_QP_SIZE, newdev);
+ if (qp_connect) {
+ dev_err(&scifdev->sdev->dev,
+ "failed to setup qp_connect %d\n", qp_connect);
+ goto qp_connect_error;
+ }
+
+ newdev->db = sdev->hw_ops->next_db(sdev);
+ newdev->cookie = sdev->hw_ops->request_irq(sdev, scif_intr_handler,
+ "SCIF_INTR", newdev,
+ newdev->db);
+ if (IS_ERR(newdev->cookie))
+ goto qp_connect_error;
+ newdev->qpairs->magic = SCIFEP_MAGIC;
+ newdev->qpairs->qp_state = SCIF_QP_OFFLINE;
+
+ msg->uop = SCIF_NODE_ADD_ACK;
+ msg->dst.node = msg->src.node;
+ msg->src.node = scif_info.nodeid;
+ msg->payload[0] = qp_offset;
+ msg->payload[2] = newdev->db;
+ scif_nodeqp_send(&scif_dev[SCIF_MGMT_NODE], msg);
+ return;
+qp_connect_error:
+ kfree(newdev->qpairs);
+ newdev->qpairs = NULL;
+qp_alloc_error:
+ iounmap(newdev->mmio.va);
+ newdev->mmio.va = NULL;
+mmio_map_error:
+interrupt_setup_error:
+ dev_err(&scifdev->sdev->dev,
+ "node add failed for node %d\n", msg->src.node);
+ msg->uop = SCIF_NODE_ADD_NACK;
+ msg->dst.node = msg->src.node;
+ msg->src.node = scif_info.nodeid;
+ scif_nodeqp_send(&scif_dev[SCIF_MGMT_NODE], msg);
+}
+
+void scif_poll_qp_state(struct work_struct *work)
+{
+#define SCIF_NODE_QP_RETRY 100
+#define SCIF_NODE_QP_TIMEOUT 100
+ struct scif_dev *peerdev = container_of(work, struct scif_dev,
+ p2p_dwork.work);
+ struct scif_qp *qp = &peerdev->qpairs[0];
+
+ if (qp->qp_state != SCIF_QP_ONLINE ||
+ qp->remote_qp->qp_state != SCIF_QP_ONLINE) {
+ if (peerdev->p2p_retry++ == SCIF_NODE_QP_RETRY) {
+ dev_err(&peerdev->sdev->dev,
+ "Warning: QP check timeout with state %d\n",
+ qp->qp_state);
+ goto timeout;
+ }
+ schedule_delayed_work(&peerdev->p2p_dwork,
+ msecs_to_jiffies(SCIF_NODE_QP_TIMEOUT));
+ return;
+ }
+ scif_peer_register_device(peerdev);
+ return;
+timeout:
+ dev_err(&peerdev->sdev->dev,
+ "%s %d remote node %d offline, state = 0x%x\n",
+ __func__, __LINE__, peerdev->node, qp->qp_state);
+ qp->remote_qp->qp_state = SCIF_QP_OFFLINE;
+ scif_cleanup_scifdev(peerdev);
+}
+
+/**
+ * scif_node_add_ack() - Respond to SCIF_NODE_ADD_ACK interrupt message
+ * @scifdev: Remote SCIF device node
+ * @msg: Interrupt message
+ *
+ * After a MIC node receives the SCIF_NODE_ADD_ACK message it send this
+ * message to the mgmt node to confirm the sequence is finished.
+ *
+ */
+static __always_inline void
+scif_node_add_ack(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_dev *peerdev;
+ struct scif_qp *qp;
+ struct scif_dev *dst_dev = &scif_dev[msg->dst.node];
+
+ dev_dbg(&scifdev->sdev->dev,
+ "Scifdev %d received SCIF_NODE_ADD_ACK msg src %d dst %d\n",
+ scifdev->node, msg->src.node, msg->dst.node);
+ dev_dbg(&scifdev->sdev->dev,
+ "payload %llx %llx %llx %llx\n", msg->payload[0],
+ msg->payload[1], msg->payload[2], msg->payload[3]);
+ if (scif_is_mgmt_node()) {
+ /*
+ * the lock serializes with scif_qp_response_ack. The mgmt node
+ * is forwarding the NODE_ADD_ACK message from src to dst we
+ * need to make sure that the dst has already received a
+ * NODE_ADD for src and setup its end of the qp to dst
+ */
+ mutex_lock(&scif_info.conflock);
+ msg->payload[1] = scif_info.maxid;
+ scif_nodeqp_send(dst_dev, msg);
+ mutex_unlock(&scif_info.conflock);
+ return;
+ }
+ peerdev = &scif_dev[msg->src.node];
+ peerdev->sdev = scif_dev[SCIF_MGMT_NODE].sdev;
+ peerdev->node = msg->src.node;
+
+ qp = &peerdev->qpairs[0];
+
+ if ((scif_setup_qp_connect_response(peerdev, &peerdev->qpairs[0],
+ msg->payload[0])))
+ goto local_error;
+ peerdev->rdb = msg->payload[2];
+ qp->remote_qp->qp_state = SCIF_QP_ONLINE;
+ schedule_delayed_work(&peerdev->p2p_dwork, 0);
+ return;
+local_error:
+ scif_cleanup_scifdev(peerdev);
+}
+
+/**
+ * scif_node_add_nack: Respond to SCIF_NODE_ADD_NACK interrupt message
+ * @msg: Interrupt message
+ *
+ * SCIF_NODE_ADD failed, so inform the waiting wq.
+ */
+static __always_inline void
+scif_node_add_nack(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ if (scif_is_mgmt_node()) {
+ struct scif_dev *dst_dev = &scif_dev[msg->dst.node];
+
+ dev_dbg(&scifdev->sdev->dev,
+ "SCIF_NODE_ADD_NACK received from %d\n", scifdev->node);
+ scif_nodeqp_send(dst_dev, msg);
+ }
+}
+
+/*
+ * scif_node_remove: Handle SCIF_NODE_REMOVE message
+ * @msg: Interrupt message
+ *
+ * Handle node removal.
+ */
+static __always_inline void
+scif_node_remove(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ int node = msg->payload[0];
+ struct scif_dev *scdev = &scif_dev[node];
+
+ scdev->node_remove_ack_pending = true;
+ scif_handle_remove_node(node);
+}
+
+/*
+ * scif_node_remove_ack: Handle SCIF_NODE_REMOVE_ACK message
+ * @msg: Interrupt message
+ *
+ * The peer has acked a SCIF_NODE_REMOVE message.
+ */
+static __always_inline void
+scif_node_remove_ack(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_dev *sdev = &scif_dev[msg->payload[0]];
+
+ atomic_inc(&sdev->disconn_rescnt);
+ wake_up(&sdev->disconn_wq);
+}
+
+static void
+scif_msg_unknown(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ /* Bogus Node Qp Message? */
+ dev_err(&scifdev->sdev->dev,
+ "Unknown message 0x%xn scifdev->node 0x%x\n",
+ msg->uop, scifdev->node);
+}
+
+static void (*scif_intr_func[SCIF_MAX_MSG + 1])
+ (struct scif_dev *, struct scifmsg *msg) = {
+ scif_msg_unknown, /* Error */
+ scif_init, /* SCIF_INIT */
+ scif_exit, /* SCIF_EXIT */
+ scif_exit_ack, /* SCIF_EXIT_ACK */
+ scif_node_add, /* SCIF_NODE_ADD */
+ scif_node_add_ack, /* SCIF_NODE_ADD_ACK */
+ scif_node_add_nack, /* SCIF_NODE_ADD_NACK */
+ scif_node_remove, /* SCIF_NODE_REMOVE */
+ scif_node_remove_ack, /* SCIF_NODE_REMOVE_ACK */
+};
+
+/**
+ * scif_nodeqp_msg_handler() - Common handler for node messages
+ * @scifdev: Remote device to respond to
+ * @qp: Remote memory pointer
+ * @msg: The message to be handled.
+ *
+ * This routine calls the appropriate routine to handle a Node Qp
+ * message receipt
+ */
+static int scif_max_msg_id = SCIF_MAX_MSG;
+
+static void
+scif_nodeqp_msg_handler(struct scif_dev *scifdev,
+ struct scif_qp *qp, struct scifmsg *msg)
+{
+ scif_display_message(scifdev, msg, "Rcvd");
+
+ if (msg->uop > (u32)scif_max_msg_id) {
+ /* Bogus Node Qp Message? */
+ dev_err(&scifdev->sdev->dev,
+ "Unknown message 0x%xn scifdev->node 0x%x\n",
+ msg->uop, scifdev->node);
+ return;
+ }
+
+ scif_intr_func[msg->uop](scifdev, msg);
+}
+
+/**
+ * scif_nodeqp_intrhandler() - Interrupt handler for node messages
+ * @scifdev: Remote device to respond to
+ * @qp: Remote memory pointer
+ *
+ * This routine is triggered by the interrupt mechanism. It reads
+ * messages from the node queue RB and calls the Node QP Message handling
+ * routine.
+ */
+void scif_nodeqp_intrhandler(struct scif_dev *scifdev, struct scif_qp *qp)
+{
+ struct scifmsg msg;
+ int read_size;
+
+ do {
+ read_size = scif_rb_get_next(&qp->inbound_q, &msg, sizeof(msg));
+ if (!read_size)
+ break;
+ scif_nodeqp_msg_handler(scifdev, qp, &msg);
+ /*
+ * The node queue pair is unmapped so skip the read pointer
+ * update after receipt of a SCIF_EXIT_ACK
+ */
+ if (SCIF_EXIT_ACK == msg.uop)
+ break;
+ scif_rb_update_read_ptr(&qp->inbound_q);
+ } while (1);
+}
+
+/**
+ * scif_loopb_wq_handler - Loopback Workqueue Handler.
+ * @work: loop back work
+ *
+ * This work queue routine is invoked by the loopback work queue handler.
+ * It grabs the recv lock, dequeues any available messages from the head
+ * of the loopback message list, calls the node QP message handler,
+ * waits for it to return, then frees up this message and dequeues more
+ * elements of the list if available.
+ */
+static void scif_loopb_wq_handler(struct work_struct *unused)
+{
+ struct scif_dev *scifdev = scif_info.loopb_dev;
+ struct scif_qp *qp = scifdev->qpairs;
+ struct scif_loopb_msg *msg;
+
+ do {
+ msg = NULL;
+ spin_lock(&qp->recv_lock);
+ if (!list_empty(&scif_info.loopb_recv_q)) {
+ msg = list_first_entry(&scif_info.loopb_recv_q,
+ struct scif_loopb_msg,
+ list);
+ list_del(&msg->list);
+ }
+ spin_unlock(&qp->recv_lock);
+
+ if (msg) {
+ scif_nodeqp_msg_handler(scifdev, qp, &msg->msg);
+ kfree(msg);
+ }
+ } while (msg);
+}
+
+/**
+ * scif_loopb_msg_handler() - Workqueue handler for loopback messages.
+ * @scifdev: SCIF device
+ * @qp: Queue pair.
+ *
+ * This work queue routine is triggered when a loopback message is received.
+ *
+ * We need special handling for receiving Node Qp messages on a loopback SCIF
+ * device via two workqueues for receiving messages.
+ *
+ * The reason we need the extra workqueue which is not required with *normal*
+ * non-loopback SCIF devices is the potential classic deadlock described below:
+ *
+ * Thread A tries to send a message on a loopback SCIF device and blocks since
+ * there is no space in the RB while it has the send_lock held or another
+ * lock called lock X for example.
+ *
+ * Thread B: The Loopback Node QP message receive workqueue receives the message
+ * and tries to send a message (eg an ACK) to the loopback SCIF device. It tries
+ * to grab the send lock again or lock X and deadlocks with Thread A. The RB
+ * cannot be drained any further due to this classic deadlock.
+ *
+ * In order to avoid deadlocks as mentioned above we have an extra level of
+ * indirection achieved by having two workqueues.
+ * 1) The first workqueue whose handler is scif_loopb_msg_handler reads
+ * messages from the Node QP RB, adds them to a list and queues work for the
+ * second workqueue.
+ *
+ * 2) The second workqueue whose handler is scif_loopb_wq_handler dequeues
+ * messages from the list, handles them, frees up the memory and dequeues
+ * more elements from the list if possible.
+ */
+int
+scif_loopb_msg_handler(struct scif_dev *scifdev, struct scif_qp *qp)
+{
+ int read_size;
+ struct scif_loopb_msg *msg;
+
+ do {
+ msg = kmalloc(sizeof(*msg), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+ read_size = scif_rb_get_next(&qp->inbound_q, &msg->msg,
+ sizeof(struct scifmsg));
+ if (read_size != sizeof(struct scifmsg)) {
+ kfree(msg);
+ scif_rb_update_read_ptr(&qp->inbound_q);
+ break;
+ }
+ spin_lock(&qp->recv_lock);
+ list_add_tail(&msg->list, &scif_info.loopb_recv_q);
+ spin_unlock(&qp->recv_lock);
+ queue_work(scif_info.loopb_wq, &scif_info.loopb_work);
+ scif_rb_update_read_ptr(&qp->inbound_q);
+ } while (read_size == sizeof(struct scifmsg));
+ return read_size;
+}
+
+/**
+ * scif_setup_loopback_qp - One time setup work for Loopback Node Qp.
+ * @scifdev: SCIF device
+ *
+ * Sets up the required loopback workqueues, queue pairs and ring buffers
+ */
+int scif_setup_loopback_qp(struct scif_dev *scifdev)
+{
+ int err = 0;
+ void *local_q;
+ struct scif_qp *qp;
+ struct scif_peer_dev *spdev;
+
+ err = scif_setup_intr_wq(scifdev);
+ if (err)
+ goto exit;
+ INIT_LIST_HEAD(&scif_info.loopb_recv_q);
+ snprintf(scif_info.loopb_wqname, sizeof(scif_info.loopb_wqname),
+ "SCIF LOOPB %d", scifdev->node);
+ scif_info.loopb_wq =
+ alloc_ordered_workqueue(scif_info.loopb_wqname, 0);
+ if (!scif_info.loopb_wq) {
+ err = -ENOMEM;
+ goto destroy_intr;
+ }
+ INIT_WORK(&scif_info.loopb_work, scif_loopb_wq_handler);
+ /* Allocate Self Qpair */
+ scifdev->qpairs = kzalloc(sizeof(*scifdev->qpairs), GFP_KERNEL);
+ if (!scifdev->qpairs) {
+ err = -ENOMEM;
+ goto destroy_loopb_wq;
+ }
+
+ qp = scifdev->qpairs;
+ qp->magic = SCIFEP_MAGIC;
+ spin_lock_init(&qp->send_lock);
+ spin_lock_init(&qp->recv_lock);
+
+ local_q = kzalloc(SCIF_NODE_QP_SIZE, GFP_KERNEL);
+ if (!local_q) {
+ err = -ENOMEM;
+ goto free_qpairs;
+ }
+ /*
+ * For loopback the inbound_q and outbound_q are essentially the same
+ * since the Node sends a message on the loopback interface to the
+ * outbound_q which is then received on the inbound_q.
+ */
+ scif_rb_init(&qp->outbound_q,
+ &qp->local_read,
+ &qp->local_write,
+ local_q, get_count_order(SCIF_NODE_QP_SIZE));
+
+ scif_rb_init(&qp->inbound_q,
+ &qp->local_read,
+ &qp->local_write,
+ local_q, get_count_order(SCIF_NODE_QP_SIZE));
+ scif_info.nodeid = scifdev->node;
+ spdev = scif_peer_register_device(scifdev);
+ if (IS_ERR(spdev)) {
+ err = PTR_ERR(spdev);
+ goto free_local_q;
+ }
+ scif_info.loopb_dev = scifdev;
+ return err;
+free_local_q:
+ kfree(local_q);
+free_qpairs:
+ kfree(scifdev->qpairs);
+destroy_loopb_wq:
+ destroy_workqueue(scif_info.loopb_wq);
+destroy_intr:
+ scif_destroy_intr_wq(scifdev);
+exit:
+ return err;
+}
+
+/**
+ * scif_destroy_loopback_qp - One time uninit work for Loopback Node Qp
+ * @scifdev: SCIF device
+ *
+ * Destroys the workqueues and frees up the Ring Buffer and Queue Pair memory.
+ */
+int scif_destroy_loopback_qp(struct scif_dev *scifdev)
+{
+ struct scif_peer_dev *spdev;
+
+ rcu_read_lock();
+ spdev = rcu_dereference(scifdev->spdev);
+ rcu_read_unlock();
+ if (spdev)
+ scif_peer_unregister_device(spdev);
+ destroy_workqueue(scif_info.loopb_wq);
+ scif_destroy_intr_wq(scifdev);
+ kfree(scifdev->qpairs->outbound_q.rb_base);
+ kfree(scifdev->qpairs);
+ scifdev->sdev = NULL;
+ scif_info.loopb_dev = NULL;
+ return 0;
+}
+
+void scif_destroy_p2p(struct scif_dev *scifdev)
+{
+ struct scif_dev *peer_dev;
+ struct scif_p2p_info *p2p;
+ struct list_head *pos, *tmp;
+ int bd;
+
+ mutex_lock(&scif_info.conflock);
+ /* Free P2P mappings in the given node for all its peer nodes */
+ list_for_each_safe(pos, tmp, &scifdev->p2p) {
+ p2p = list_entry(pos, struct scif_p2p_info, ppi_list);
+ dma_unmap_sg(&scifdev->sdev->dev, p2p->ppi_sg[SCIF_PPI_MMIO],
+ p2p->sg_nentries[SCIF_PPI_MMIO],
+ DMA_BIDIRECTIONAL);
+ dma_unmap_sg(&scifdev->sdev->dev, p2p->ppi_sg[SCIF_PPI_APER],
+ p2p->sg_nentries[SCIF_PPI_APER],
+ DMA_BIDIRECTIONAL);
+ scif_p2p_freesg(p2p->ppi_sg[SCIF_PPI_MMIO]);
+ scif_p2p_freesg(p2p->ppi_sg[SCIF_PPI_APER]);
+ list_del(pos);
+ kfree(p2p);
+ }
+
+ /* Free P2P mapping created in the peer nodes for the given node */
+ for (bd = SCIF_MGMT_NODE + 1; bd <= scif_info.maxid; bd++) {
+ peer_dev = &scif_dev[bd];
+ list_for_each_safe(pos, tmp, &peer_dev->p2p) {
+ p2p = list_entry(pos, struct scif_p2p_info, ppi_list);
+ if (p2p->ppi_peer_id == scifdev->node) {
+ dma_unmap_sg(&peer_dev->sdev->dev,
+ p2p->ppi_sg[SCIF_PPI_MMIO],
+ p2p->sg_nentries[SCIF_PPI_MMIO],
+ DMA_BIDIRECTIONAL);
+ dma_unmap_sg(&peer_dev->sdev->dev,
+ p2p->ppi_sg[SCIF_PPI_APER],
+ p2p->sg_nentries[SCIF_PPI_APER],
+ DMA_BIDIRECTIONAL);
+ scif_p2p_freesg(p2p->ppi_sg[SCIF_PPI_MMIO]);
+ scif_p2p_freesg(p2p->ppi_sg[SCIF_PPI_APER]);
+ list_del(pos);
+ kfree(p2p);
+ }
+ }
+ }
+ mutex_unlock(&scif_info.conflock);
+}
projects / GitHub / LineageOS / G12 / android_kernel_amlogic_linux-4.9.git / commitdiff