diff options
| -rw-r--r-- | drivers/misc/mic/scif/scif_api.c | 43 | ||||
| -rw-r--r-- | drivers/misc/mic/scif/scif_main.c | 88 | ||||
| -rw-r--r-- | drivers/misc/mic/scif/scif_main.h | 5 | ||||
| -rw-r--r-- | drivers/misc/mic/scif/scif_nm.c | 10 | ||||
| -rw-r--r-- | drivers/misc/mic/scif/scif_nodeqp.c | 65 | ||||
| -rw-r--r-- | drivers/misc/mic/scif/scif_peer_bus.c | 165 | ||||
| -rw-r--r-- | drivers/misc/mic/scif/scif_peer_bus.h | 42 | ||||
| -rw-r--r-- | include/linux/scif.h | 58 |
8 files changed, 255 insertions, 221 deletions
diff --git a/drivers/misc/mic/scif/scif_api.c b/drivers/misc/mic/scif/scif_api.c index bf2d70fcd055..b47d56d5d93c 100644 --- a/drivers/misc/mic/scif/scif_api.c +++ b/drivers/misc/mic/scif/scif_api.c @@ -1430,3 +1430,46 @@ int scif_get_node_ids(u16 *nodes, int len, u16 *self) return online; } EXPORT_SYMBOL_GPL(scif_get_node_ids); + +static int scif_add_client_dev(struct device *dev, struct subsys_interface *si) +{ + struct scif_client *client = + container_of(si, struct scif_client, si); + struct scif_peer_dev *spdev = + container_of(dev, struct scif_peer_dev, dev); + + if (client->probe) + client->probe(spdev); + return 0; +} + +static void scif_remove_client_dev(struct device *dev, + struct subsys_interface *si) +{ + struct scif_client *client = + container_of(si, struct scif_client, si); + struct scif_peer_dev *spdev = + container_of(dev, struct scif_peer_dev, dev); + + if (client->remove) + client->remove(spdev); +} + +void scif_client_unregister(struct scif_client *client) +{ + subsys_interface_unregister(&client->si); +} +EXPORT_SYMBOL_GPL(scif_client_unregister); + +int scif_client_register(struct scif_client *client) +{ + struct subsys_interface *si = &client->si; + + si->name = client->name; + si->subsys = &scif_peer_bus; + si->add_dev = scif_add_client_dev; + si->remove_dev = scif_remove_client_dev; + + return subsys_interface_register(&client->si); +} +EXPORT_SYMBOL_GPL(scif_client_register); diff --git a/drivers/misc/mic/scif/scif_main.c b/drivers/misc/mic/scif/scif_main.c index 6ce851f5c7e6..f90bd06900cb 100644 --- a/drivers/misc/mic/scif/scif_main.c +++ b/drivers/misc/mic/scif/scif_main.c @@ -80,35 +80,6 @@ irqreturn_t scif_intr_handler(int irq, void *data) return IRQ_HANDLED; } -static int scif_peer_probe(struct scif_peer_dev *spdev) -{ - struct scif_dev *scifdev = &scif_dev[spdev->dnode]; - - mutex_lock(&scif_info.conflock); - scif_info.total++; - scif_info.maxid = max_t(u32, spdev->dnode, scif_info.maxid); - mutex_unlock(&scif_info.conflock); - rcu_assign_pointer(scifdev->spdev, spdev); - - /* In the future SCIF kernel client devices will be added here */ - return 0; -} - -static void scif_peer_remove(struct scif_peer_dev *spdev) -{ - struct scif_dev *scifdev = &scif_dev[spdev->dnode]; - - /* In the future SCIF kernel client devices will be removed here */ - spdev = rcu_dereference(scifdev->spdev); - if (spdev) - RCU_INIT_POINTER(scifdev->spdev, NULL); - synchronize_rcu(); - - mutex_lock(&scif_info.conflock); - scif_info.total--; - mutex_unlock(&scif_info.conflock); -} - static void scif_qp_setup_handler(struct work_struct *work) { struct scif_dev *scifdev = container_of(work, struct scif_dev, @@ -139,20 +110,13 @@ static void scif_qp_setup_handler(struct work_struct *work) } } -static int scif_setup_scifdev(struct scif_hw_dev *sdev) +static int scif_setup_scifdev(void) { + /* We support a maximum of 129 SCIF nodes including the mgmt node */ +#define MAX_SCIF_NODES 129 int i; - u8 num_nodes; + u8 num_nodes = MAX_SCIF_NODES; - if (sdev->snode) { - struct mic_bootparam __iomem *bp = sdev->rdp; - - num_nodes = ioread8(&bp->tot_nodes); - } else { - struct mic_bootparam *bp = sdev->dp; - - num_nodes = bp->tot_nodes; - } scif_dev = kcalloc(num_nodes, sizeof(*scif_dev), GFP_KERNEL); if (!scif_dev) return -ENOMEM; @@ -163,7 +127,7 @@ static int scif_setup_scifdev(struct scif_hw_dev *sdev) scifdev->exit = OP_IDLE; init_waitqueue_head(&scifdev->disconn_wq); mutex_init(&scifdev->lock); - INIT_WORK(&scifdev->init_msg_work, scif_qp_response_ack); + INIT_WORK(&scifdev->peer_add_work, scif_add_peer_device); INIT_DELAYED_WORK(&scifdev->p2p_dwork, scif_poll_qp_state); INIT_DELAYED_WORK(&scifdev->qp_dwork, @@ -181,27 +145,21 @@ static void scif_destroy_scifdev(void) static int scif_probe(struct scif_hw_dev *sdev) { - struct scif_dev *scifdev; + struct scif_dev *scifdev = &scif_dev[sdev->dnode]; int rc; dev_set_drvdata(&sdev->dev, sdev); + scifdev->sdev = sdev; + if (1 == atomic_add_return(1, &g_loopb_cnt)) { - struct scif_dev *loopb_dev; + struct scif_dev *loopb_dev = &scif_dev[sdev->snode]; - rc = scif_setup_scifdev(sdev); - if (rc) - goto exit; - scifdev = &scif_dev[sdev->dnode]; - scifdev->sdev = sdev; - loopb_dev = &scif_dev[sdev->snode]; loopb_dev->sdev = sdev; rc = scif_setup_loopback_qp(loopb_dev); if (rc) - goto free_sdev; - } else { - scifdev = &scif_dev[sdev->dnode]; - scifdev->sdev = sdev; + goto exit; } + rc = scif_setup_intr_wq(scifdev); if (rc) goto destroy_loopb; @@ -237,8 +195,6 @@ destroy_intr: destroy_loopb: if (atomic_dec_and_test(&g_loopb_cnt)) scif_destroy_loopback_qp(&scif_dev[sdev->snode]); -free_sdev: - scif_destroy_scifdev(); exit: return rc; } @@ -290,13 +246,6 @@ static void scif_remove(struct scif_hw_dev *sdev) scifdev->sdev = NULL; } -static struct scif_peer_driver scif_peer_driver = { - .driver.name = KBUILD_MODNAME, - .driver.owner = THIS_MODULE, - .probe = scif_peer_probe, - .remove = scif_peer_remove, -}; - static struct scif_hw_dev_id id_table[] = { { MIC_SCIF_DEV, SCIF_DEV_ANY_ID }, { 0 }, @@ -312,6 +261,8 @@ static struct scif_driver scif_driver = { static int _scif_init(void) { + int rc; + spin_lock_init(&scif_info.eplock); spin_lock_init(&scif_info.nb_connect_lock); spin_lock_init(&scif_info.port_lock); @@ -326,10 +277,15 @@ static int _scif_init(void) init_waitqueue_head(&scif_info.exitwq); scif_info.en_msg_log = 0; scif_info.p2p_enable = 1; + rc = scif_setup_scifdev(); + if (rc) + goto error; INIT_WORK(&scif_info.misc_work, scif_misc_handler); INIT_WORK(&scif_info.conn_work, scif_conn_handler); idr_init(&scif_ports); return 0; +error: + return rc; } static void _scif_exit(void) @@ -347,12 +303,9 @@ static int __init scif_init(void) rc = scif_peer_bus_init(); if (rc) goto exit; - rc = scif_peer_register_driver(&scif_peer_driver); - if (rc) - goto peer_bus_exit; rc = scif_register_driver(&scif_driver); if (rc) - goto unreg_scif_peer; + goto peer_bus_exit; rc = misc_register(mdev); if (rc) goto unreg_scif; @@ -360,8 +313,6 @@ static int __init scif_init(void) return 0; unreg_scif: scif_unregister_driver(&scif_driver); -unreg_scif_peer: - scif_peer_unregister_driver(&scif_peer_driver); peer_bus_exit: scif_peer_bus_exit(); exit: @@ -374,7 +325,6 @@ static void __exit scif_exit(void) scif_exit_debugfs(); misc_deregister(&scif_info.mdev); scif_unregister_driver(&scif_driver); - scif_peer_unregister_driver(&scif_peer_driver); scif_peer_bus_exit(); _scif_exit(); } diff --git a/drivers/misc/mic/scif/scif_main.h b/drivers/misc/mic/scif/scif_main.h index 87c13279a8f0..b0795b059803 100644 --- a/drivers/misc/mic/scif/scif_main.h +++ b/drivers/misc/mic/scif/scif_main.h @@ -140,7 +140,7 @@ struct scif_p2p_info { * @db: doorbell the peer will trigger to generate an interrupt on self * @rdb: Doorbell to trigger on the peer to generate an interrupt on the peer * @cookie: Cookie received while registering the interrupt handler - * init_msg_work: work scheduled for SCIF_INIT message processing + * @peer_add_work: Work for handling device_add for peer devices * @p2p_dwork: Delayed work to enable polling for P2P state * @qp_dwork: Delayed work for enabling polling for remote QP information * @p2p_retry: Number of times to retry polling of P2P state @@ -166,7 +166,7 @@ struct scif_dev { int db; int rdb; struct mic_irq *cookie; - struct work_struct init_msg_work; + struct work_struct peer_add_work; struct delayed_work p2p_dwork; struct delayed_work qp_dwork; int p2p_retry; @@ -183,6 +183,7 @@ struct scif_dev { extern struct scif_info scif_info; extern struct idr scif_ports; +extern struct bus_type scif_peer_bus; extern struct scif_dev *scif_dev; extern const struct file_operations scif_fops; extern const struct file_operations scif_anon_fops; diff --git a/drivers/misc/mic/scif/scif_nm.c b/drivers/misc/mic/scif/scif_nm.c index 9b4c5382d6a7..f1b1b97b3636 100644 --- a/drivers/misc/mic/scif/scif_nm.c +++ b/drivers/misc/mic/scif/scif_nm.c @@ -147,14 +147,8 @@ void scif_cleanup_scifdev(struct scif_dev *dev) void scif_handle_remove_node(int node) { struct scif_dev *scifdev = &scif_dev[node]; - struct scif_peer_dev *spdev; - - rcu_read_lock(); - spdev = rcu_dereference(scifdev->spdev); - rcu_read_unlock(); - if (spdev) - scif_peer_unregister_device(spdev); - else + + if (scif_peer_unregister_device(scifdev)) scif_send_acks(scifdev); } diff --git a/drivers/misc/mic/scif/scif_nodeqp.c b/drivers/misc/mic/scif/scif_nodeqp.c index 6dfdae3452d6..5cdb9f088350 100644 --- a/drivers/misc/mic/scif/scif_nodeqp.c +++ b/drivers/misc/mic/scif/scif_nodeqp.c @@ -260,6 +260,11 @@ int scif_setup_qp_connect_response(struct scif_dev *scifdev, r_buf, get_count_order(remote_size)); /* + * Because the node QP may already be processing an INIT message, set + * the read pointer so the cached read offset isn't lost + */ + qp->remote_qp->local_read = qp->inbound_q.current_read_offset; + /* * resetup the inbound_q now that we know where the * inbound_read really is. */ @@ -529,27 +534,6 @@ static void scif_p2p_setup(void) } } -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", @@ -682,13 +666,14 @@ scif_init(struct scif_dev *scifdev, struct scifmsg *msg) * 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_peer_register_device(scifdev); + + if (scif_is_mgmt_node()) { + mutex_lock(&scif_info.conflock); + scif_p2p_setup(); + mutex_unlock(&scif_info.conflock); + } } /** @@ -838,13 +823,13 @@ void scif_poll_qp_state(struct work_struct *work) 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_peer_unregister_device(peerdev); scif_cleanup_scifdev(peerdev); } @@ -894,6 +879,9 @@ scif_node_add_ack(struct scif_dev *scifdev, struct scifmsg *msg) goto local_error; peerdev->rdb = msg->payload[2]; qp->remote_qp->qp_state = SCIF_QP_ONLINE; + + scif_peer_register_device(peerdev); + schedule_delayed_work(&peerdev->p2p_dwork, 0); return; local_error: @@ -1169,7 +1157,6 @@ 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) @@ -1216,15 +1203,11 @@ int scif_setup_loopback_qp(struct scif_dev *scifdev) &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_peer_register_device(scifdev); + scif_info.loopb_dev = scifdev; return err; -free_local_q: - kfree(local_q); free_qpairs: kfree(scifdev->qpairs); destroy_loopb_wq: @@ -1243,13 +1226,7 @@ exit: */ 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); + scif_peer_unregister_device(scifdev); destroy_workqueue(scif_info.loopb_wq); scif_destroy_intr_wq(scifdev); kfree(scifdev->qpairs->outbound_q.rb_base); diff --git a/drivers/misc/mic/scif/scif_peer_bus.c b/drivers/misc/mic/scif/scif_peer_bus.c index 589ae9ad2501..547bf7bdd5c2 100644 --- a/drivers/misc/mic/scif/scif_peer_bus.c +++ b/drivers/misc/mic/scif/scif_peer_bus.c @@ -24,93 +24,138 @@ dev_to_scif_peer(struct device *dev) return container_of(dev, struct scif_peer_dev, dev); } -static inline struct scif_peer_driver * -drv_to_scif_peer(struct device_driver *drv) -{ - return container_of(drv, struct scif_peer_driver, driver); -} +struct bus_type scif_peer_bus = { + .name = "scif_peer_bus", +}; -static int scif_peer_dev_match(struct device *dv, struct device_driver *dr) +static void scif_peer_release_dev(struct device *d) { - return !strncmp(dev_name(dv), dr->name, 4); + struct scif_peer_dev *sdev = dev_to_scif_peer(d); + struct scif_dev *scifdev = &scif_dev[sdev->dnode]; + + scif_cleanup_scifdev(scifdev); + kfree(sdev); } -static int scif_peer_dev_probe(struct device *d) +static int scif_peer_initialize_device(struct scif_dev *scifdev) { - struct scif_peer_dev *dev = dev_to_scif_peer(d); - struct scif_peer_driver *drv = drv_to_scif_peer(dev->dev.driver); + struct scif_peer_dev *spdev; + int ret; - return drv->probe(dev); -} + spdev = kzalloc(sizeof(*spdev), GFP_KERNEL); + if (!spdev) { + ret = -ENOMEM; + goto err; + } -static int scif_peer_dev_remove(struct device *d) -{ - struct scif_peer_dev *dev = dev_to_scif_peer(d); - struct scif_peer_driver *drv = drv_to_scif_peer(dev->dev.driver); + spdev->dev.parent = scifdev->sdev->dev.parent; + spdev->dev.release = scif_peer_release_dev; + spdev->dnode = scifdev->node; + spdev->dev.bus = &scif_peer_bus; + dev_set_name(&spdev->dev, "scif_peer-dev%u", spdev->dnode); + + device_initialize(&spdev->dev); + get_device(&spdev->dev); + rcu_assign_pointer(scifdev->spdev, spdev); - drv->remove(dev); + mutex_lock(&scif_info.conflock); + scif_info.total++; + scif_info.maxid = max_t(u32, spdev->dnode, scif_info.maxid); + mutex_unlock(&scif_info.conflock); return 0; +err: + dev_err(&scifdev->sdev->dev, + "dnode %d: initialize_device rc %d\n", scifdev->node, ret); + return ret; } -static struct bus_type scif_peer_bus = { - .name = "scif_peer_bus", - .match = scif_peer_dev_match, - .probe = scif_peer_dev_probe, - .remove = scif_peer_dev_remove, -}; - -int scif_peer_register_driver(struct scif_peer_driver *driver) +static int scif_peer_add_device(struct scif_dev *scifdev) { - driver->driver.bus = &scif_peer_bus; - return driver_register(&driver->driver); + struct scif_peer_dev *spdev = rcu_dereference(scifdev->spdev); + int ret; + + ret = device_add(&spdev->dev); + put_device(&spdev->dev); + if (ret) { + dev_err(&scifdev->sdev->dev, + "dnode %d: peer device_add failed\n", scifdev->node); + goto put_spdev; + } + dev_dbg(&spdev->dev, "Added peer dnode %d\n", spdev->dnode); + return 0; +put_spdev: + RCU_INIT_POINTER(scifdev->spdev, NULL); + synchronize_rcu(); + put_device(&spdev->dev); + + mutex_lock(&scif_info.conflock); + scif_info.total--; + mutex_unlock(&scif_info.conflock); + return ret; } -void scif_peer_unregister_driver(struct scif_peer_driver *driver) +void scif_add_peer_device(struct work_struct *work) { - driver_unregister(&driver->driver); + struct scif_dev *scifdev = container_of(work, struct scif_dev, + peer_add_work); + + scif_peer_add_device(scifdev); } -static void scif_peer_release_dev(struct device *d) +/* + * Peer device registration is split into a device_initialize and a device_add. + * The reason for doing this is as follows: First, peer device registration + * itself cannot be done in the message processing thread and must be delegated + * to another workqueue, otherwise if SCIF client probe, called during peer + * device registration, calls scif_connect(..), it will block the message + * processing thread causing a deadlock. Next, device_initialize is done in the + * "top-half" message processing thread and device_add in the "bottom-half" + * workqueue. If this is not done, SCIF_CNCT_REQ message processing executing + * concurrently with SCIF_INIT message processing is unable to get a reference + * on the peer device, thereby failing the connect request. + */ +void scif_peer_register_device(struct scif_dev *scifdev) { - struct scif_peer_dev *sdev = dev_to_scif_peer(d); - struct scif_dev *scifdev = &scif_dev[sdev->dnode]; + int ret; - scif_cleanup_scifdev(scifdev); - kfree(sdev); + mutex_lock(&scifdev->lock); + ret = scif_peer_initialize_device(scifdev); + if (ret) + goto exit; + schedule_work(&scifdev->peer_add_work); +exit: + mutex_unlock(&scifdev->lock); } -struct scif_peer_dev * -scif_peer_register_device(struct scif_dev *scifdev) +int scif_peer_unregister_device(struct scif_dev *scifdev) { - int ret; struct scif_peer_dev *spdev; - spdev = kzalloc(sizeof(*spdev), GFP_KERNEL); - if (!spdev) - return ERR_PTR(-ENOMEM); - - spdev->dev.parent = scifdev->sdev->dev.parent; - spdev->dev.release = scif_peer_release_dev; - spdev->dnode = scifdev->node; - spdev->dev.bus = &scif_peer_bus; + mutex_lock(&scifdev->lock); + /* Flush work to ensure device register is complete */ + flush_work(&scifdev->peer_add_work); - dev_set_name(&spdev->dev, "scif_peer-dev%u", spdev->dnode); /* - * device_register() causes the bus infrastructure to look for a - * matching driver. + * Continue holding scifdev->lock since theoretically unregister_device + * can be called simultaneously from multiple threads */ - ret = device_register(&spdev->dev); - if (ret) - goto free_spdev; - return spdev; -free_spdev: - kfree(spdev); - return ERR_PTR(ret); -} - -void scif_peer_unregister_device(struct scif_peer_dev *sdev) -{ - device_unregister(&sdev->dev); + spdev = rcu_dereference(scifdev->spdev); + if (!spdev) { + mutex_unlock(&scifdev->lock); + return -ENODEV; + } + + RCU_INIT_POINTER(scifdev->spdev, NULL); + synchronize_rcu(); + mutex_unlock(&scifdev->lock); + + dev_dbg(&spdev->dev, "Removing peer dnode %d\n", spdev->dnode); + device_unregister(&spdev->dev); + + mutex_lock(&scif_info.conflock); + scif_info.total--; + mutex_unlock(&scif_info.conflock); + return 0; } int scif_peer_bus_init(void) diff --git a/drivers/misc/mic/scif/scif_peer_bus.h b/drivers/misc/mic/scif/scif_peer_bus.h index 33f0dbb30152..a3b8dd2edaa5 100644 --- a/drivers/misc/mic/scif/scif_peer_bus.h +++ b/drivers/misc/mic/scif/scif_peer_bus.h @@ -19,47 +19,13 @@ #include <linux/device.h> #include <linux/mic_common.h> - -/* - * Peer devices show up as PCIe devices for the mgmt node but not the cards. - * The mgmt node discovers all the cards on the PCIe bus and informs the other - * cards about their peers. Upon notification of a peer a node adds a peer - * device to the peer bus to maintain symmetry in the way devices are - * discovered across all nodes in the SCIF network. - */ -/** - * scif_peer_dev - representation of a peer SCIF device - * @dev: underlying device - * @dnode - The destination node which this device will communicate with. - */ -struct scif_peer_dev { - struct device dev; - u8 dnode; -}; - -/** - * scif_peer_driver - operations for a scif_peer I/O driver - * @driver: underlying device driver (populate name and owner). - * @id_table: the ids serviced by this driver. - * @probe: the function to call when a device is found. Returns 0 or -errno. - * @remove: the function to call when a device is removed. - */ -struct scif_peer_driver { - struct device_driver driver; - const struct scif_peer_dev_id *id_table; - - int (*probe)(struct scif_peer_dev *dev); - void (*remove)(struct scif_peer_dev *dev); -}; +#include <linux/scif.h> struct scif_dev; -int scif_peer_register_driver(struct scif_peer_driver *driver); -void scif_peer_unregister_driver(struct scif_peer_driver *driver); - -struct scif_peer_dev *scif_peer_register_device(struct scif_dev *sdev); -void scif_peer_unregister_device(struct scif_peer_dev *sdev); - +void scif_add_peer_device(struct work_struct *work); +void scif_peer_register_device(struct scif_dev *sdev); +int scif_peer_unregister_device(struct scif_dev *scifdev); int scif_peer_bus_init(void); void scif_peer_bus_exit(void); #endif /* _SCIF_PEER_BUS_H */ diff --git a/include/linux/scif.h b/include/linux/scif.h index b1923ad2ddd3..fd62c051b166 100644 --- a/include/linux/scif.h +++ b/include/linux/scif.h @@ -55,6 +55,7 @@ #include <linux/types.h> #include <linux/poll.h> +#include <linux/device.h> #include <linux/scif_ioctl.h> #define SCIF_ACCEPT_SYNC 1 @@ -105,6 +106,37 @@ struct scif_pollepd { short revents; }; +/** + * scif_peer_dev - representation of a peer SCIF device + * + * Peer devices show up as PCIe devices for the mgmt node but not the cards. + * The mgmt node discovers all the cards on the PCIe bus and informs the other + * cards about their peers. Upon notification of a peer a node adds a peer + * device to the peer bus to maintain symmetry in the way devices are + * discovered across all nodes in the SCIF network. + * + * @dev: underlying device + * @dnode - The destination node which this device will communicate with. + */ +struct scif_peer_dev { + struct device dev; + u8 dnode; +}; + +/** + * scif_client - representation of a SCIF client + * @name: client name + * @probe - client method called when a peer device is registered + * @remove - client method called when a peer device is unregistered + * @si - subsys_interface used internally for implementing SCIF clients + */ +struct scif_client { + const char *name; + void (*probe)(struct scif_peer_dev *spdev); + void (*remove)(struct scif_peer_dev *spdev); + struct subsys_interface si; +}; + #define SCIF_OPEN_FAILED ((scif_epd_t)-1) #define SCIF_REGISTER_FAILED ((off_t)-1) #define SCIF_MMAP_FAILED ((void *)-1) @@ -1064,4 +1096,30 @@ int scif_get_node_ids(u16 *nodes, int len, u16 *self); */ int scif_poll(struct scif_pollepd *epds, unsigned int nepds, long timeout); +/** + * scif_client_register() - Register a SCIF client + * @client: client to be registered + * + * scif_client_register() registers a SCIF client. The probe() method + * of the client is called when SCIF peer devices come online and the + * remove() method is called when the peer devices disappear. + * + * Return: + * Upon successful completion, scif_client_register() returns a non-negative + * value. Otherwise the return value is the same as subsys_interface_register() + * in the kernel. + */ +int scif_client_register(struct scif_client *client); + +/** + * scif_client_unregister() - Unregister a SCIF client + * @client: client to be unregistered + * + * scif_client_unregister() unregisters a SCIF client. + * + * Return: + * None + */ +void scif_client_unregister(struct scif_client *client); + #endif /* __SCIF_H__ */ |