diff options
Diffstat (limited to 'drivers/misc/mic/scif/scif_api.c')
| -rw-r--r-- | drivers/misc/mic/scif/scif_api.c | 1276 |
1 files changed, 1276 insertions, 0 deletions
diff --git a/drivers/misc/mic/scif/scif_api.c b/drivers/misc/mic/scif/scif_api.c new file mode 100644 index 000000000000..f39d3135a9ef --- /dev/null +++ b/drivers/misc/mic/scif/scif_api.c @@ -0,0 +1,1276 @@ +/* + * 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 <linux/scif.h> +#include "scif_main.h" +#include "scif_map.h" + +static const char * const scif_ep_states[] = { + "Unbound", + "Bound", + "Listening", + "Connected", + "Connecting", + "Mapping", + "Closing", + "Close Listening", + "Disconnected", + "Zombie"}; + +enum conn_async_state { + ASYNC_CONN_IDLE = 1, /* ep setup for async connect */ + ASYNC_CONN_INPROGRESS, /* async connect in progress */ + ASYNC_CONN_FLUSH_WORK /* async work flush in progress */ +}; + +scif_epd_t scif_open(void) +{ + struct scif_endpt *ep; + + might_sleep(); + ep = kzalloc(sizeof(*ep), GFP_KERNEL); + if (!ep) + goto err_ep_alloc; + + ep->qp_info.qp = kzalloc(sizeof(*ep->qp_info.qp), GFP_KERNEL); + if (!ep->qp_info.qp) + goto err_qp_alloc; + + spin_lock_init(&ep->lock); + mutex_init(&ep->sendlock); + mutex_init(&ep->recvlock); + + ep->state = SCIFEP_UNBOUND; + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI open: ep %p success\n", ep); + return ep; + +err_qp_alloc: + kfree(ep); +err_ep_alloc: + return NULL; +} +EXPORT_SYMBOL_GPL(scif_open); + +/* + * scif_disconnect_ep - Disconnects the endpoint if found + * @epd: The end point returned from scif_open() + */ +static struct scif_endpt *scif_disconnect_ep(struct scif_endpt *ep) +{ + struct scifmsg msg; + struct scif_endpt *fep = NULL; + struct scif_endpt *tmpep; + struct list_head *pos, *tmpq; + int err; + + /* + * Wake up any threads blocked in send()/recv() before closing + * out the connection. Grabbing and releasing the send/recv lock + * will ensure that any blocked senders/receivers have exited for + * Ring 0 endpoints. It is a Ring 0 bug to call send/recv after + * close. Ring 3 endpoints are not affected since close will not + * be called while there are IOCTLs executing. + */ + wake_up_interruptible(&ep->sendwq); + wake_up_interruptible(&ep->recvwq); + mutex_lock(&ep->sendlock); + mutex_unlock(&ep->sendlock); + mutex_lock(&ep->recvlock); + mutex_unlock(&ep->recvlock); + + /* Remove from the connected list */ + mutex_lock(&scif_info.connlock); + list_for_each_safe(pos, tmpq, &scif_info.connected) { + tmpep = list_entry(pos, struct scif_endpt, list); + if (tmpep == ep) { + list_del(pos); + fep = tmpep; + spin_lock(&ep->lock); + break; + } + } + + if (!fep) { + /* + * The other side has completed the disconnect before + * the end point can be removed from the list. Therefore + * the ep lock is not locked, traverse the disconnected + * list to find the endpoint and release the conn lock. + */ + list_for_each_safe(pos, tmpq, &scif_info.disconnected) { + tmpep = list_entry(pos, struct scif_endpt, list); + if (tmpep == ep) { + list_del(pos); + break; + } + } + mutex_unlock(&scif_info.connlock); + return NULL; + } + + init_completion(&ep->discon); + msg.uop = SCIF_DISCNCT; + msg.src = ep->port; + msg.dst = ep->peer; + msg.payload[0] = (u64)ep; + msg.payload[1] = ep->remote_ep; + + err = scif_nodeqp_send(ep->remote_dev, &msg); + spin_unlock(&ep->lock); + mutex_unlock(&scif_info.connlock); + + if (!err) + /* Wait for the remote node to respond with SCIF_DISCNT_ACK */ + wait_for_completion_timeout(&ep->discon, + SCIF_NODE_ALIVE_TIMEOUT); + return ep; +} + +int scif_close(scif_epd_t epd) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + struct scif_endpt *tmpep; + struct list_head *pos, *tmpq; + enum scif_epd_state oldstate; + bool flush_conn; + + dev_dbg(scif_info.mdev.this_device, "SCIFAPI close: ep %p %s\n", + ep, scif_ep_states[ep->state]); + might_sleep(); + spin_lock(&ep->lock); + flush_conn = (ep->conn_async_state == ASYNC_CONN_INPROGRESS); + spin_unlock(&ep->lock); + + if (flush_conn) + flush_work(&scif_info.conn_work); + + spin_lock(&ep->lock); + oldstate = ep->state; + + ep->state = SCIFEP_CLOSING; + + switch (oldstate) { + case SCIFEP_ZOMBIE: + case SCIFEP_DISCONNECTED: + spin_unlock(&ep->lock); + /* Remove from the disconnected list */ + mutex_lock(&scif_info.connlock); + list_for_each_safe(pos, tmpq, &scif_info.disconnected) { + tmpep = list_entry(pos, struct scif_endpt, list); + if (tmpep == ep) { + list_del(pos); + break; + } + } + mutex_unlock(&scif_info.connlock); + break; + case SCIFEP_UNBOUND: + case SCIFEP_BOUND: + case SCIFEP_CONNECTING: + spin_unlock(&ep->lock); + break; + case SCIFEP_MAPPING: + case SCIFEP_CONNECTED: + case SCIFEP_CLOSING: + { + spin_unlock(&ep->lock); + scif_disconnect_ep(ep); + break; + } + case SCIFEP_LISTENING: + case SCIFEP_CLLISTEN: + { + struct scif_conreq *conreq; + struct scifmsg msg; + struct scif_endpt *aep; + + spin_unlock(&ep->lock); + spin_lock(&scif_info.eplock); + + /* remove from listen list */ + list_for_each_safe(pos, tmpq, &scif_info.listen) { + tmpep = list_entry(pos, struct scif_endpt, list); + if (tmpep == ep) + list_del(pos); + } + /* Remove any dangling accepts */ + while (ep->acceptcnt) { + aep = list_first_entry(&ep->li_accept, + struct scif_endpt, liacceptlist); + list_del(&aep->liacceptlist); + scif_put_port(aep->port.port); + list_for_each_safe(pos, tmpq, &scif_info.uaccept) { + tmpep = list_entry(pos, struct scif_endpt, + miacceptlist); + if (tmpep == aep) { + list_del(pos); + break; + } + } + spin_unlock(&scif_info.eplock); + mutex_lock(&scif_info.connlock); + list_for_each_safe(pos, tmpq, &scif_info.connected) { + tmpep = list_entry(pos, + struct scif_endpt, list); + if (tmpep == aep) { + list_del(pos); + break; + } + } + list_for_each_safe(pos, tmpq, &scif_info.disconnected) { + tmpep = list_entry(pos, + struct scif_endpt, list); + if (tmpep == aep) { + list_del(pos); + break; + } + } + mutex_unlock(&scif_info.connlock); + scif_teardown_ep(aep); + spin_lock(&scif_info.eplock); + scif_add_epd_to_zombie_list(aep, SCIF_EPLOCK_HELD); + ep->acceptcnt--; + } + + spin_lock(&ep->lock); + spin_unlock(&scif_info.eplock); + + /* Remove and reject any pending connection requests. */ + while (ep->conreqcnt) { + conreq = list_first_entry(&ep->conlist, + struct scif_conreq, list); + list_del(&conreq->list); + + msg.uop = SCIF_CNCT_REJ; + msg.dst.node = conreq->msg.src.node; + msg.dst.port = conreq->msg.src.port; + msg.payload[0] = conreq->msg.payload[0]; + msg.payload[1] = conreq->msg.payload[1]; + /* + * No Error Handling on purpose for scif_nodeqp_send(). + * If the remote node is lost we still want free the + * connection requests on the self node. + */ + scif_nodeqp_send(&scif_dev[conreq->msg.src.node], + &msg); + ep->conreqcnt--; + kfree(conreq); + } + + spin_unlock(&ep->lock); + /* If a kSCIF accept is waiting wake it up */ + wake_up_interruptible(&ep->conwq); + break; + } + } + scif_put_port(ep->port.port); + scif_teardown_ep(ep); + scif_add_epd_to_zombie_list(ep, !SCIF_EPLOCK_HELD); + return 0; +} +EXPORT_SYMBOL_GPL(scif_close); + +/** + * scif_flush() - Wakes up any blocking accepts. The endpoint will no longer + * accept new connections. + * @epd: The end point returned from scif_open() + */ +int __scif_flush(scif_epd_t epd) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + + switch (ep->state) { + case SCIFEP_LISTENING: + { + ep->state = SCIFEP_CLLISTEN; + + /* If an accept is waiting wake it up */ + wake_up_interruptible(&ep->conwq); + break; + } + default: + break; + } + return 0; +} + +int scif_bind(scif_epd_t epd, u16 pn) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + int ret = 0; + int tmp; + + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI bind: ep %p %s requested port number %d\n", + ep, scif_ep_states[ep->state], pn); + if (pn) { + /* + * Similar to IETF RFC 1700, SCIF ports below + * SCIF_ADMIN_PORT_END can only be bound by system (or root) + * processes or by processes executed by privileged users. + */ + if (pn < SCIF_ADMIN_PORT_END && !capable(CAP_SYS_ADMIN)) { + ret = -EACCES; + goto scif_bind_admin_exit; + } + } + + spin_lock(&ep->lock); + if (ep->state == SCIFEP_BOUND) { + ret = -EINVAL; + goto scif_bind_exit; + } else if (ep->state != SCIFEP_UNBOUND) { + ret = -EISCONN; + goto scif_bind_exit; + } + + if (pn) { + tmp = scif_rsrv_port(pn); + if (tmp != pn) { + ret = -EINVAL; + goto scif_bind_exit; + } + } else { + pn = scif_get_new_port(); + if (!pn) { + ret = -ENOSPC; + goto scif_bind_exit; + } + } + + ep->state = SCIFEP_BOUND; + ep->port.node = scif_info.nodeid; + ep->port.port = pn; + ep->conn_async_state = ASYNC_CONN_IDLE; + ret = pn; + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI bind: bound to port number %d\n", pn); +scif_bind_exit: + spin_unlock(&ep->lock); +scif_bind_admin_exit: + return ret; +} +EXPORT_SYMBOL_GPL(scif_bind); + +int scif_listen(scif_epd_t epd, int backlog) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI listen: ep %p %s\n", ep, scif_ep_states[ep->state]); + spin_lock(&ep->lock); + switch (ep->state) { + case SCIFEP_ZOMBIE: + case SCIFEP_CLOSING: + case SCIFEP_CLLISTEN: + case SCIFEP_UNBOUND: + case SCIFEP_DISCONNECTED: + spin_unlock(&ep->lock); + return -EINVAL; + case SCIFEP_LISTENING: + case SCIFEP_CONNECTED: + case SCIFEP_CONNECTING: + case SCIFEP_MAPPING: + spin_unlock(&ep->lock); + return -EISCONN; + case SCIFEP_BOUND: + break; + } + + ep->state = SCIFEP_LISTENING; + ep->backlog = backlog; + + ep->conreqcnt = 0; + ep->acceptcnt = 0; + INIT_LIST_HEAD(&ep->conlist); + init_waitqueue_head(&ep->conwq); + INIT_LIST_HEAD(&ep->li_accept); + spin_unlock(&ep->lock); + + /* + * Listen status is complete so delete the qp information not needed + * on a listen before placing on the list of listening ep's + */ + scif_teardown_ep(ep); + ep->qp_info.qp = NULL; + + spin_lock(&scif_info.eplock); + list_add_tail(&ep->list, &scif_info.listen); + spin_unlock(&scif_info.eplock); + return 0; +} +EXPORT_SYMBOL_GPL(scif_listen); + +/* + ************************************************************************ + * SCIF connection flow: + * + * 1) A SCIF listening endpoint can call scif_accept(..) to wait for SCIF + * connections via a SCIF_CNCT_REQ message + * 2) A SCIF endpoint can initiate a SCIF connection by calling + * scif_connect(..) which calls scif_setup_qp_connect(..) which + * allocates the local qp for the endpoint ring buffer and then sends + * a SCIF_CNCT_REQ to the remote node and waits for a SCIF_CNCT_GNT or + * a SCIF_CNCT_REJ message + * 3) The peer node handles a SCIF_CNCT_REQ via scif_cnctreq_resp(..) which + * wakes up any threads blocked in step 1 or sends a SCIF_CNCT_REJ + * message otherwise + * 4) A thread blocked waiting for incoming connections allocates its local + * endpoint QP and ring buffer following which it sends a SCIF_CNCT_GNT + * and waits for a SCIF_CNCT_GNT(N)ACK. If the allocation fails then + * the node sends a SCIF_CNCT_REJ message + * 5) Upon receipt of a SCIF_CNCT_GNT or a SCIF_CNCT_REJ message the + * connecting endpoint is woken up as part of handling + * scif_cnctgnt_resp(..) following which it maps the remote endpoints' + * QP, updates its outbound QP and sends a SCIF_CNCT_GNTACK message on + * success or a SCIF_CNCT_GNTNACK message on failure and completes + * the scif_connect(..) API + * 6) Upon receipt of a SCIF_CNCT_GNT(N)ACK the accepting endpoint blocked + * in step 4 is woken up and completes the scif_accept(..) API + * 7) The SCIF connection is now established between the two SCIF endpoints. + */ +static int scif_conn_func(struct scif_endpt *ep) +{ + int err = 0; + struct scifmsg msg; + struct device *spdev; + + /* Initiate the first part of the endpoint QP setup */ + err = scif_setup_qp_connect(ep->qp_info.qp, &ep->qp_info.qp_offset, + SCIF_ENDPT_QP_SIZE, ep->remote_dev); + if (err) { + dev_err(&ep->remote_dev->sdev->dev, + "%s err %d qp_offset 0x%llx\n", + __func__, err, ep->qp_info.qp_offset); + ep->state = SCIFEP_BOUND; + goto connect_error_simple; + } + + spdev = scif_get_peer_dev(ep->remote_dev); + if (IS_ERR(spdev)) { + err = PTR_ERR(spdev); + goto cleanup_qp; + } + /* Format connect message and send it */ + msg.src = ep->port; + msg.dst = ep->conn_port; + msg.uop = SCIF_CNCT_REQ; + msg.payload[0] = (u64)ep; + msg.payload[1] = ep->qp_info.qp_offset; + err = _scif_nodeqp_send(ep->remote_dev, &msg); + if (err) + goto connect_error_dec; + scif_put_peer_dev(spdev); + /* + * Wait for the remote node to respond with SCIF_CNCT_GNT or + * SCIF_CNCT_REJ message. + */ + err = wait_event_timeout(ep->conwq, ep->state != SCIFEP_CONNECTING, + SCIF_NODE_ALIVE_TIMEOUT); + if (!err) { + dev_err(&ep->remote_dev->sdev->dev, + "%s %d timeout\n", __func__, __LINE__); + ep->state = SCIFEP_BOUND; + } + spdev = scif_get_peer_dev(ep->remote_dev); + if (IS_ERR(spdev)) { + err = PTR_ERR(spdev); + goto cleanup_qp; + } + if (ep->state == SCIFEP_MAPPING) { + err = scif_setup_qp_connect_response(ep->remote_dev, + ep->qp_info.qp, + ep->qp_info.gnt_pld); + /* + * If the resource to map the queue are not available then + * we need to tell the other side to terminate the accept + */ + if (err) { + dev_err(&ep->remote_dev->sdev->dev, + "%s %d err %d\n", __func__, __LINE__, err); + msg.uop = SCIF_CNCT_GNTNACK; + msg.payload[0] = ep->remote_ep; + _scif_nodeqp_send(ep->remote_dev, &msg); + ep->state = SCIFEP_BOUND; + goto connect_error_dec; + } + + msg.uop = SCIF_CNCT_GNTACK; + msg.payload[0] = ep->remote_ep; + err = _scif_nodeqp_send(ep->remote_dev, &msg); + if (err) { + ep->state = SCIFEP_BOUND; + goto connect_error_dec; + } + ep->state = SCIFEP_CONNECTED; + mutex_lock(&scif_info.connlock); + list_add_tail(&ep->list, &scif_info.connected); + mutex_unlock(&scif_info.connlock); + dev_dbg(&ep->remote_dev->sdev->dev, + "SCIFAPI connect: ep %p connected\n", ep); + } else if (ep->state == SCIFEP_BOUND) { + dev_dbg(&ep->remote_dev->sdev->dev, + "SCIFAPI connect: ep %p connection refused\n", ep); + err = -ECONNREFUSED; + goto connect_error_dec; + } + scif_put_peer_dev(spdev); + return err; +connect_error_dec: + scif_put_peer_dev(spdev); +cleanup_qp: + scif_cleanup_ep_qp(ep); +connect_error_simple: + return err; +} + +/* + * scif_conn_handler: + * + * Workqueue handler for servicing non-blocking SCIF connect + * + */ +void scif_conn_handler(struct work_struct *work) +{ + struct scif_endpt *ep; + + do { + ep = NULL; + spin_lock(&scif_info.nb_connect_lock); + if (!list_empty(&scif_info.nb_connect_list)) { + ep = list_first_entry(&scif_info.nb_connect_list, + struct scif_endpt, conn_list); + list_del(&ep->conn_list); + } + spin_unlock(&scif_info.nb_connect_lock); + if (ep) + ep->conn_err = scif_conn_func(ep); + } while (ep); +} + +int __scif_connect(scif_epd_t epd, struct scif_port_id *dst, bool non_block) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + int err = 0; + struct scif_dev *remote_dev; + struct device *spdev; + + dev_dbg(scif_info.mdev.this_device, "SCIFAPI connect: ep %p %s\n", ep, + scif_ep_states[ep->state]); + + if (!scif_dev || dst->node > scif_info.maxid) + return -ENODEV; + + might_sleep(); + + remote_dev = &scif_dev[dst->node]; + spdev = scif_get_peer_dev(remote_dev); + if (IS_ERR(spdev)) { + err = PTR_ERR(spdev); + return err; + } + + spin_lock(&ep->lock); + switch (ep->state) { + case SCIFEP_ZOMBIE: + case SCIFEP_CLOSING: + err = -EINVAL; + break; + case SCIFEP_DISCONNECTED: + if (ep->conn_async_state == ASYNC_CONN_INPROGRESS) + ep->conn_async_state = ASYNC_CONN_FLUSH_WORK; + else + err = -EINVAL; + break; + case SCIFEP_LISTENING: + case SCIFEP_CLLISTEN: + err = -EOPNOTSUPP; + break; + case SCIFEP_CONNECTING: + case SCIFEP_MAPPING: + if (ep->conn_async_state == ASYNC_CONN_INPROGRESS) + err = -EINPROGRESS; + else + err = -EISCONN; + break; + case SCIFEP_CONNECTED: + if (ep->conn_async_state == ASYNC_CONN_INPROGRESS) + ep->conn_async_state = ASYNC_CONN_FLUSH_WORK; + else + err = -EISCONN; + break; + case SCIFEP_UNBOUND: + ep->port.port = scif_get_new_port(); + if (!ep->port.port) { + err = -ENOSPC; + } else { + ep->port.node = scif_info.nodeid; + ep->conn_async_state = ASYNC_CONN_IDLE; + } + /* Fall through */ + case SCIFEP_BOUND: + /* + * If a non-blocking connect has been already initiated + * (conn_async_state is either ASYNC_CONN_INPROGRESS or + * ASYNC_CONN_FLUSH_WORK), the end point could end up in + * SCIF_BOUND due an error in the connection process + * (e.g., connection refused) If conn_async_state is + * ASYNC_CONN_INPROGRESS - transition to ASYNC_CONN_FLUSH_WORK + * so that the error status can be collected. If the state is + * already ASYNC_CONN_FLUSH_WORK - then set the error to + * EINPROGRESS since some other thread is waiting to collect + * error status. + */ + if (ep->conn_async_state == ASYNC_CONN_INPROGRESS) { + ep->conn_async_state = ASYNC_CONN_FLUSH_WORK; + } else if (ep->conn_async_state == ASYNC_CONN_FLUSH_WORK) { + err = -EINPROGRESS; + } else { + ep->conn_port = *dst; + init_waitqueue_head(&ep->sendwq); + init_waitqueue_head(&ep->recvwq); + init_waitqueue_head(&ep->conwq); + ep->conn_async_state = 0; + + if (unlikely(non_block)) + ep->conn_async_state = ASYNC_CONN_INPROGRESS; + } + break; + } + + if (err || ep->conn_async_state == ASYNC_CONN_FLUSH_WORK) + goto connect_simple_unlock1; + + ep->state = SCIFEP_CONNECTING; + ep->remote_dev = &scif_dev[dst->node]; + ep->qp_info.qp->magic = SCIFEP_MAGIC; + if (ep->conn_async_state == ASYNC_CONN_INPROGRESS) { + spin_lock(&scif_info.nb_connect_lock); + list_add_tail(&ep->conn_list, &scif_info.nb_connect_list); + spin_unlock(&scif_info.nb_connect_lock); + err = -EINPROGRESS; + schedule_work(&scif_info.conn_work); + } +connect_simple_unlock1: + spin_unlock(&ep->lock); + scif_put_peer_dev(spdev); + if (err) { + return err; + } else if (ep->conn_async_state == ASYNC_CONN_FLUSH_WORK) { + flush_work(&scif_info.conn_work); + err = ep->conn_err; + spin_lock(&ep->lock); + ep->conn_async_state = ASYNC_CONN_IDLE; + spin_unlock(&ep->lock); + } else { + err = scif_conn_func(ep); + } + return err; +} + +int scif_connect(scif_epd_t epd, struct scif_port_id *dst) +{ + return __scif_connect(epd, dst, false); +} +EXPORT_SYMBOL_GPL(scif_connect); + +/** + * scif_accept() - Accept a connection request from the remote node + * + * The function accepts a connection request from the remote node. Successful + * complete is indicate by a new end point being created and passed back + * to the caller for future reference. + * + * Upon successful complete a zero will be returned and the peer information + * will be filled in. + * + * If the end point is not in the listening state -EINVAL will be returned. + * + * If during the connection sequence resource allocation fails the -ENOMEM + * will be returned. + * + * If the function is called with the ASYNC flag set and no connection requests + * are pending it will return -EAGAIN. + * + * If the remote side is not sending any connection requests the caller may + * terminate this function with a signal. If so a -EINTR will be returned. + */ +int scif_accept(scif_epd_t epd, struct scif_port_id *peer, + scif_epd_t *newepd, int flags) +{ + struct scif_endpt *lep = (struct scif_endpt *)epd; + struct scif_endpt *cep; + struct scif_conreq *conreq; + struct scifmsg msg; + int err; + struct device *spdev; + + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI accept: ep %p %s\n", lep, scif_ep_states[lep->state]); + + if (flags & ~SCIF_ACCEPT_SYNC) + return -EINVAL; + + if (!peer || !newepd) + return -EINVAL; + + might_sleep(); + spin_lock(&lep->lock); + if (lep->state != SCIFEP_LISTENING) { + spin_unlock(&lep->lock); + return -EINVAL; + } + + if (!lep->conreqcnt && !(flags & SCIF_ACCEPT_SYNC)) { + /* No connection request present and we do not want to wait */ + spin_unlock(&lep->lock); + return -EAGAIN; + } + + lep->files = current->files; +retry_connection: + spin_unlock(&lep->lock); + /* Wait for the remote node to send us a SCIF_CNCT_REQ */ + err = wait_event_interruptible(lep->conwq, + (lep->conreqcnt || + (lep->state != SCIFEP_LISTENING))); + if (err) + return err; + + if (lep->state != SCIFEP_LISTENING) + return -EINTR; + + spin_lock(&lep->lock); + + if (!lep->conreqcnt) + goto retry_connection; + + /* Get the first connect request off the list */ + conreq = list_first_entry(&lep->conlist, struct scif_conreq, list); + list_del(&conreq->list); + lep->conreqcnt--; + spin_unlock(&lep->lock); + + /* Fill in the peer information */ + peer->node = conreq->msg.src.node; + peer->port = conreq->msg.src.port; + + cep = kzalloc(sizeof(*cep), GFP_KERNEL); + if (!cep) { + err = -ENOMEM; + goto scif_accept_error_epalloc; + } + spin_lock_init(&cep->lock); + mutex_init(&cep->sendlock); + mutex_init(&cep->recvlock); + cep->state = SCIFEP_CONNECTING; + cep->remote_dev = &scif_dev[peer->node]; + cep->remote_ep = conreq->msg.payload[0]; + + cep->qp_info.qp = kzalloc(sizeof(*cep->qp_info.qp), GFP_KERNEL); + if (!cep->qp_info.qp) { + err = -ENOMEM; + goto scif_accept_error_qpalloc; + } + + cep->qp_info.qp->magic = SCIFEP_MAGIC; + spdev = scif_get_peer_dev(cep->remote_dev); + if (IS_ERR(spdev)) { + err = PTR_ERR(spdev); + goto scif_accept_error_map; + } + err = scif_setup_qp_accept(cep->qp_info.qp, &cep->qp_info.qp_offset, + conreq->msg.payload[1], SCIF_ENDPT_QP_SIZE, + cep->remote_dev); + if (err) { + dev_dbg(&cep->remote_dev->sdev->dev, + "SCIFAPI accept: ep %p new %p scif_setup_qp_accept %d qp_offset 0x%llx\n", + lep, cep, err, cep->qp_info.qp_offset); + scif_put_peer_dev(spdev); + goto scif_accept_error_map; + } + + cep->port.node = lep->port.node; + cep->port.port = lep->port.port; + cep->peer.node = peer->node; + cep->peer.port = peer->port; + init_waitqueue_head(&cep->sendwq); + init_waitqueue_head(&cep->recvwq); + init_waitqueue_head(&cep->conwq); + + msg.uop = SCIF_CNCT_GNT; + msg.src = cep->port; + msg.payload[0] = cep->remote_ep; + msg.payload[1] = cep->qp_info.qp_offset; + msg.payload[2] = (u64)cep; + + err = _scif_nodeqp_send(cep->remote_dev, &msg); + scif_put_peer_dev(spdev); + if (err) + goto scif_accept_error_map; +retry: + /* Wait for the remote node to respond with SCIF_CNCT_GNT(N)ACK */ + err = wait_event_timeout(cep->conwq, cep->state != SCIFEP_CONNECTING, + SCIF_NODE_ACCEPT_TIMEOUT); + if (!err && scifdev_alive(cep)) + goto retry; + err = !err ? -ENODEV : 0; + if (err) + goto scif_accept_error_map; + kfree(conreq); + + spin_lock(&cep->lock); + + if (cep->state == SCIFEP_CLOSING) { + /* + * Remote failed to allocate resources and NAKed the grant. + * There is at this point nothing referencing the new end point. + */ + spin_unlock(&cep->lock); + scif_teardown_ep(cep); + kfree(cep); + + /* If call with sync flag then go back and wait. */ + if (flags & SCIF_ACCEPT_SYNC) { + spin_lock(&lep->lock); + goto retry_connection; + } + return -EAGAIN; + } + + scif_get_port(cep->port.port); + *newepd = (scif_epd_t)cep; + spin_unlock(&cep->lock); + return 0; +scif_accept_error_map: + scif_teardown_ep(cep); +scif_accept_error_qpalloc: + kfree(cep); +scif_accept_error_epalloc: + msg.uop = SCIF_CNCT_REJ; + msg.dst.node = conreq->msg.src.node; + msg.dst.port = conreq->msg.src.port; + msg.payload[0] = conreq->msg.payload[0]; + msg.payload[1] = conreq->msg.payload[1]; + scif_nodeqp_send(&scif_dev[conreq->msg.src.node], &msg); + kfree(conreq); + return err; +} +EXPORT_SYMBOL_GPL(scif_accept); + +/* + * scif_msg_param_check: + * @epd: The end point returned from scif_open() + * @len: Length to receive + * @flags: blocking or non blocking + * + * Validate parameters for messaging APIs scif_send(..)/scif_recv(..). + */ +static inline int scif_msg_param_check(scif_epd_t epd, int len, int flags) +{ + int ret = -EINVAL; + + if (len < 0) + goto err_ret; + if (flags && (!(flags & SCIF_RECV_BLOCK))) + goto err_ret; + ret = 0; +err_ret: + return ret; +} + +static int _scif_send(scif_epd_t epd, void *msg, int len, int flags) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + struct scifmsg notif_msg; + int curr_xfer_len = 0, sent_len = 0, write_count; + int ret = 0; + struct scif_qp *qp = ep->qp_info.qp; + + if (flags & SCIF_SEND_BLOCK) + might_sleep(); + + spin_lock(&ep->lock); + while (sent_len != len && SCIFEP_CONNECTED == ep->state) { + write_count = scif_rb_space(&qp->outbound_q); + if (write_count) { + /* Best effort to send as much data as possible */ + curr_xfer_len = min(len - sent_len, write_count); + ret = scif_rb_write(&qp->outbound_q, msg, + curr_xfer_len); + if (ret < 0) + break; + /* Success. Update write pointer */ + scif_rb_commit(&qp->outbound_q); + /* + * Send a notification to the peer about the + * produced data message. + */ + notif_msg.src = ep->port; + notif_msg.uop = SCIF_CLIENT_SENT; + notif_msg.payload[0] = ep->remote_ep; + ret = _scif_nodeqp_send(ep->remote_dev, ¬if_msg); + if (ret) + break; + sent_len += curr_xfer_len; + msg = msg + curr_xfer_len; + continue; + } + curr_xfer_len = min(len - sent_len, SCIF_ENDPT_QP_SIZE - 1); + /* Not enough RB space. return for the Non Blocking case */ + if (!(flags & SCIF_SEND_BLOCK)) + break; + + spin_unlock(&ep->lock); + /* Wait for a SCIF_CLIENT_RCVD message in the Blocking case */ + ret = + wait_event_interruptible(ep->sendwq, + (SCIFEP_CONNECTED != ep->state) || + (scif_rb_space(&qp->outbound_q) >= + curr_xfer_len)); + spin_lock(&ep->lock); + if (ret) + break; + } + if (sent_len) + ret = sent_len; + else if (!ret && SCIFEP_CONNECTED != ep->state) + ret = SCIFEP_DISCONNECTED == ep->state ? + -ECONNRESET : -ENOTCONN; + spin_unlock(&ep->lock); + return ret; +} + +static int _scif_recv(scif_epd_t epd, void *msg, int len, int flags) +{ + int read_size; + struct scif_endpt *ep = (struct scif_endpt *)epd; + struct scifmsg notif_msg; + int curr_recv_len = 0, remaining_len = len, read_count; + int ret = 0; + struct scif_qp *qp = ep->qp_info.qp; + + if (flags & SCIF_RECV_BLOCK) + might_sleep(); + spin_lock(&ep->lock); + while (remaining_len && (SCIFEP_CONNECTED == ep->state || + SCIFEP_DISCONNECTED == ep->state)) { + read_count = scif_rb_count(&qp->inbound_q, remaining_len); + if (read_count) { + /* + * Best effort to recv as much data as there + * are bytes to read in the RB particularly + * important for the Non Blocking case. + */ + curr_recv_len = min(remaining_len, read_count); + read_size = scif_rb_get_next(&qp->inbound_q, + msg, curr_recv_len); + if (ep->state == SCIFEP_CONNECTED) { + /* + * Update the read pointer only if the endpoint + * is still connected else the read pointer + * might no longer exist since the peer has + * freed resources! + */ + scif_rb_update_read_ptr(&qp->inbound_q); + /* + * Send a notification to the peer about the + * consumed data message only if the EP is in + * SCIFEP_CONNECTED state. + */ + notif_msg.src = ep->port; + notif_msg.uop = SCIF_CLIENT_RCVD; + notif_msg.payload[0] = ep->remote_ep; + ret = _scif_nodeqp_send(ep->remote_dev, + ¬if_msg); + if (ret) + break; + } + remaining_len -= curr_recv_len; + msg = msg + curr_recv_len; + continue; + } + /* + * Bail out now if the EP is in SCIFEP_DISCONNECTED state else + * we will keep looping forever. + */ + if (ep->state == SCIFEP_DISCONNECTED) + break; + /* + * Return in the Non Blocking case if there is no data + * to read in this iteration. + */ + if (!(flags & SCIF_RECV_BLOCK)) + break; + curr_recv_len = min(remaining_len, SCIF_ENDPT_QP_SIZE - 1); + spin_unlock(&ep->lock); + /* + * Wait for a SCIF_CLIENT_SEND message in the blocking case + * or until other side disconnects. + */ + ret = + wait_event_interruptible(ep->recvwq, + SCIFEP_CONNECTED != ep->state || + scif_rb_count(&qp->inbound_q, + curr_recv_len) + >= curr_recv_len); + spin_lock(&ep->lock); + if (ret) + break; + } + if (len - remaining_len) + ret = len - remaining_len; + else if (!ret && ep->state != SCIFEP_CONNECTED) + ret = ep->state == SCIFEP_DISCONNECTED ? + -ECONNRESET : -ENOTCONN; + spin_unlock(&ep->lock); + return ret; +} + +/** + * scif_user_send() - Send data to connection queue + * @epd: The end point returned from scif_open() + * @msg: Address to place data + * @len: Length to receive + * @flags: blocking or non blocking + * + * This function is called from the driver IOCTL entry point + * only and is a wrapper for _scif_send(). + */ +int scif_user_send(scif_epd_t epd, void __user *msg, int len, int flags) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + int err = 0; + int sent_len = 0; + char *tmp; + int loop_len; + int chunk_len = min(len, (1 << (MAX_ORDER + PAGE_SHIFT - 1))); + + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI send (U): ep %p %s\n", ep, scif_ep_states[ep->state]); + if (!len) + return 0; + + err = scif_msg_param_check(epd, len, flags); + if (err) + goto send_err; + + tmp = kmalloc(chunk_len, GFP_KERNEL); + if (!tmp) { + err = -ENOMEM; + goto send_err; + } + /* + * Grabbing the lock before breaking up the transfer in + * multiple chunks is required to ensure that messages do + * not get fragmented and reordered. + */ + mutex_lock(&ep->sendlock); + while (sent_len != len) { + loop_len = len - sent_len; + loop_len = min(chunk_len, loop_len); + if (copy_from_user(tmp, msg, loop_len)) { + err = -EFAULT; + goto send_free_err; + } + err = _scif_send(epd, tmp, loop_len, flags); + if (err < 0) + goto send_free_err; + sent_len += err; + msg += err; + if (err != loop_len) + goto send_free_err; + } +send_free_err: + mutex_unlock(&ep->sendlock); + kfree(tmp); +send_err: + return err < 0 ? err : sent_len; +} + +/** + * scif_user_recv() - Receive data from connection queue + * @epd: The end point returned from scif_open() + * @msg: Address to place data + * @len: Length to receive + * @flags: blocking or non blocking + * + * This function is called from the driver IOCTL entry point + * only and is a wrapper for _scif_recv(). + */ +int scif_user_recv(scif_epd_t epd, void __user *msg, int len, int flags) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + int err = 0; + int recv_len = 0; + char *tmp; + int loop_len; + int chunk_len = min(len, (1 << (MAX_ORDER + PAGE_SHIFT - 1))); + + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI recv (U): ep %p %s\n", ep, scif_ep_states[ep->state]); + if (!len) + return 0; + + err = scif_msg_param_check(epd, len, flags); + if (err) + goto recv_err; + + tmp = kmalloc(chunk_len, GFP_KERNEL); + if (!tmp) { + err = -ENOMEM; + goto recv_err; + } + /* + * Grabbing the lock before breaking up the transfer in + * multiple chunks is required to ensure that messages do + * not get fragmented and reordered. + */ + mutex_lock(&ep->recvlock); + while (recv_len != len) { + loop_len = len - recv_len; + loop_len = min(chunk_len, loop_len); + err = _scif_recv(epd, tmp, loop_len, flags); + if (err < 0) + goto recv_free_err; + if (copy_to_user(msg, tmp, err)) { + err = -EFAULT; + goto recv_free_err; + } + recv_len += err; + msg += err; + if (err != loop_len) + goto recv_free_err; + } +recv_free_err: + mutex_unlock(&ep->recvlock); + kfree(tmp); +recv_err: + return err < 0 ? err : recv_len; +} + +/** + * scif_send() - Send data to connection queue + * @epd: The end point returned from scif_open() + * @msg: Address to place data + * @len: Length to receive + * @flags: blocking or non blocking + * + * This function is called from the kernel mode only and is + * a wrapper for _scif_send(). + */ +int scif_send(scif_epd_t epd, void *msg, int len, int flags) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + int ret; + + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI send (K): ep %p %s\n", ep, scif_ep_states[ep->state]); + if (!len) + return 0; + + ret = scif_msg_param_check(epd, len, flags); + if (ret) + return ret; + if (!ep->remote_dev) + return -ENOTCONN; + /* + * Grab the mutex lock in the blocking case only + * to ensure messages do not get fragmented/reordered. + * The non blocking mode is protected using spin locks + * in _scif_send(). + */ + if (flags & SCIF_SEND_BLOCK) + mutex_lock(&ep->sendlock); + + ret = _scif_send(epd, msg, len, flags); + + if (flags & SCIF_SEND_BLOCK) + mutex_unlock(&ep->sendlock); + return ret; +} +EXPORT_SYMBOL_GPL(scif_send); + +/** + * scif_recv() - Receive data from connection queue + * @epd: The end point returned from scif_open() + * @msg: Address to place data + * @len: Length to receive + * @flags: blocking or non blocking + * + * This function is called from the kernel mode only and is + * a wrapper for _scif_recv(). + */ +int scif_recv(scif_epd_t epd, void *msg, int len, int flags) +{ + struct scif_endpt *ep = (struct scif_endpt *)epd; + int ret; + + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI recv (K): ep %p %s\n", ep, scif_ep_states[ep->state]); + if (!len) + return 0; + + ret = scif_msg_param_check(epd, len, flags); + if (ret) + return ret; + /* + * Grab the mutex lock in the blocking case only + * to ensure messages do not get fragmented/reordered. + * The non blocking mode is protected using spin locks + * in _scif_send(). + */ + if (flags & SCIF_RECV_BLOCK) + mutex_lock(&ep->recvlock); + + ret = _scif_recv(epd, msg, len, flags); + + if (flags & SCIF_RECV_BLOCK) + mutex_unlock(&ep->recvlock); + + return ret; +} +EXPORT_SYMBOL_GPL(scif_recv); + +int scif_get_node_ids(u16 *nodes, int len, u16 *self) +{ + int online = 0; + int offset = 0; + int node; + + if (!scif_is_mgmt_node()) + scif_get_node_info(); + + *self = scif_info.nodeid; + mutex_lock(&scif_info.conflock); + len = min_t(int, len, scif_info.total); + for (node = 0; node <= scif_info.maxid; node++) { + if (_scifdev_alive(&scif_dev[node])) { + online++; + if (offset < len) + nodes[offset++] = node; + } + } + dev_dbg(scif_info.mdev.this_device, + "SCIFAPI get_node_ids total %d online %d filled in %d nodes\n", + scif_info.total, online, offset); + mutex_unlock(&scif_info.conflock); + + return online; +} +EXPORT_SYMBOL_GPL(scif_get_node_ids); |