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);
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,
}
}
-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;
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,
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;
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;
}
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 },
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);
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)
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;
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:
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();
}
* @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
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;
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;
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);
}
&qp->remote_qp->local_write,
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.
}
}
-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",
* 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);
+ }
}
/**
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);
}
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:
int err = 0;
void *local_q;
struct scif_qp *qp;
- struct scif_peer_dev *spdev;
err = scif_setup_intr_wq(scifdev);
if (err)
&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:
*/
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);
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)
#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 */
#include <linux/types.h>
#include <linux/poll.h>
+#include <linux/device.h>
#include <linux/scif_ioctl.h>
#define SCIF_ACCEPT_SYNC 1
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)
*/
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__ */
projects / linux.git / commitdiff