*/
#define GB_OPERATION_TYPE_RESPONSE 0x80
+#define OPERATION_TIMEOUT_DEFAULT 1000 /* milliseconds */
+
/*
* XXX This needs to be coordinated with host driver parameters
+ * XXX May need to reduce to allow for message header within a page
*/
#define GB_OPERATION_MESSAGE_SIZE_MAX 4096
+static struct kmem_cache *gb_operation_cache;
+
/* Workqueue to handle Greybus operation completions. */
-static struct workqueue_struct *gb_operation_recv_workqueue;
+static struct workqueue_struct *gb_operation_workqueue;
/*
* All operation messages (both requests and responses) begin with
- * a common header that encodes the size of the data (header
- * included). This header also contains a unique identifier, which
- * is used to keep track of in-flight operations. Finally, the
- * header contains a operation type field, whose interpretation is
- * dependent on what type of device lies on the other end of the
- * connection. Response messages are distinguished from request
- * messages by setting the high bit (0x80) in the operation type
- * value.
+ * a header that encodes the size of the data (header included).
+ * This header also contains a unique identifier, which is used to
+ * keep track of in-flight operations. The header contains an
+ * operation type field, whose interpretation is dependent on what
+ * type of protocol is used over the connection.
+ *
+ * The high bit (0x80) of the operation type field is used to
+ * indicate whether the message is a request (clear) or a response
+ * (set).
+ *
+ * Response messages include an additional status byte, which
+ * communicates the result of the corresponding request. A zero
+ * status value means the operation completed successfully. Any
+ * other value indicates an error; in this case, the payload of the
+ * response message (if any) is ignored. The status byte must be
+ * zero in the header for a request message.
*
* The wire format for all numeric fields in the header is little
* endian. Any operation-specific data begins immediately after the
* header, and is 64-bit aligned.
*/
struct gb_operation_msg_hdr {
- __le16 size; /* Size in bytes of header + payload */
- __le16 id; /* Operation unique id */
- __u8 type; /* E.g GB_I2C_TYPE_* or GB_GPIO_TYPE_* */
- /* 3 bytes pad, must be zero (ignore when read) */
+ __le16 size; /* Size in bytes of header + payload */
+ __le16 operation_id; /* Operation unique id */
+ __u8 type; /* E.g GB_I2C_TYPE_* or GB_GPIO_TYPE_* */
+ __u8 result; /* Result of request (in responses only) */
+ /* 2 bytes pad, must be zero (ignore when read) */
} __aligned(sizeof(u64));
/* XXX Could be per-host device, per-module, or even per-connection */
static DEFINE_SPINLOCK(gb_operations_lock);
-static void gb_operation_insert(struct gb_operation *operation)
+static void gb_pending_operation_insert(struct gb_operation *operation)
{
struct gb_connection *connection = operation->connection;
- struct rb_root *root = &connection->pending;
- struct rb_node *node = &operation->node;
- struct rb_node **link = &root->rb_node;
- struct rb_node *above = NULL;
struct gb_operation_msg_hdr *header;
- __le16 wire_id;
/*
- * Assign the operation's id, and store it in the header of
- * both request and response message headers.
+ * Assign the operation's id and move it into its
+ * connection's pending list.
*/
- operation->id = gb_connection_operation_id(connection);
- wire_id = cpu_to_le16(operation->id);
- header = operation->request->transfer_buffer;
- header->id = wire_id;
-
- /* OK, insert the operation into its connection's tree */
spin_lock_irq(&gb_operations_lock);
-
- while (*link) {
- struct gb_operation *other;
-
- above = *link;
- other = rb_entry(above, struct gb_operation, node);
- header = other->request->transfer_buffer;
- if (other->id > operation->id)
- link = &above->rb_left;
- else if (other->id < operation->id)
- link = &above->rb_right;
- }
- rb_link_node(node, above, link);
- rb_insert_color(node, root);
-
+ operation->id = ++connection->op_cycle;
+ list_move_tail(&operation->links, &connection->pending);
spin_unlock_irq(&gb_operations_lock);
+
+ /* Store the operation id in the request header */
+ header = operation->request->header;
+ header->operation_id = cpu_to_le16(operation->id);
}
-static void gb_operation_remove(struct gb_operation *operation)
+static void gb_pending_operation_remove(struct gb_operation *operation)
{
+ struct gb_connection *connection = operation->connection;
+
+ /* Take us off of the list of pending operations */
spin_lock_irq(&gb_operations_lock);
- rb_erase(&operation->node, &operation->connection->pending);
+ list_move_tail(&operation->links, &connection->operations);
spin_unlock_irq(&gb_operations_lock);
}
static struct gb_operation *
-gb_operation_find(struct gb_connection *connection, u16 id)
+gb_pending_operation_find(struct gb_connection *connection, u16 operation_id)
{
- struct gb_operation *operation = NULL;
- struct rb_node *node;
+ struct gb_operation *operation;
bool found = false;
spin_lock_irq(&gb_operations_lock);
- node = connection->pending.rb_node;
- while (node && !found) {
- operation = rb_entry(node, struct gb_operation, node);
- if (operation->id > id)
- node = node->rb_left;
- else if (operation->id < id)
- node = node->rb_right;
- else
+ list_for_each_entry(operation, &connection->pending, links)
+ if (operation->id == operation_id) {
found = true;
- }
+ break;
+ }
spin_unlock_irq(&gb_operations_lock);
return found ? operation : NULL;
}
+static int gb_message_send(struct gb_message *message, gfp_t gfp_mask)
+{
+ struct gb_connection *connection = message->operation->connection;
+ u16 dest_cport_id = connection->interface_cport_id;
+ int ret = 0;
+
+ message->cookie = connection->hd->driver->buffer_send(connection->hd,
+ dest_cport_id,
+ message->header,
+ message->size,
+ gfp_mask);
+ if (IS_ERR(message->cookie)) {
+ ret = PTR_ERR(message->cookie);
+ message->cookie = NULL;
+ }
+ return ret;
+}
+
/*
- * An operations's response message has arrived. If no callback was
+ * Cancel a message whose buffer we have passed to the host device
+ * layer to be sent.
+ */
+static void gb_message_cancel(struct gb_message *message)
+{
+ struct greybus_host_device *hd;
+
+ if (!message->cookie)
+ return; /* Don't bother if the message isn't in flight */
+
+ hd = message->operation->connection->hd;
+ hd->driver->buffer_cancel(message->cookie);
+}
+
+/*
+ * An operation's response message has arrived. If no callback was
* supplied it was submitted for asynchronous completion, so we notify
* any waiters. Otherwise we assume calling the completion is enough
* and nobody else will be waiting.
*/
-void gb_operation_complete(struct gb_operation *operation)
+static void gb_operation_complete(struct gb_operation *operation)
{
if (operation->callback)
operation->callback(operation);
else
complete_all(&operation->completion);
+ gb_operation_put(operation);
}
-/* Wait for a submitted operation to complete */
+/*
+ * Wait for a submitted operation to complete. Returns -RESTARTSYS
+ * if the wait was interrupted. Otherwise returns the result of the
+ * operation.
+ */
int gb_operation_wait(struct gb_operation *operation)
{
int ret;
ret = wait_for_completion_interruptible(&operation->completion);
/* If interrupted, cancel the in-flight buffer */
if (ret < 0)
- ret = greybus_kill_gbuf(operation->request);
+ gb_message_cancel(operation->request);
+ else
+ ret = operation->errno;
return ret;
-
}
-
-typedef void (*gb_operation_recv_handler)(struct gb_operation *operation);
-static gb_operation_recv_handler gb_operation_recv_handlers[] = {
- [GREYBUS_PROTOCOL_CONTROL] = NULL,
- [GREYBUS_PROTOCOL_AP] = NULL,
- [GREYBUS_PROTOCOL_GPIO] = NULL,
- [GREYBUS_PROTOCOL_I2C] = NULL,
- [GREYBUS_PROTOCOL_UART] = NULL,
- [GREYBUS_PROTOCOL_HID] = NULL,
- [GREYBUS_PROTOCOL_VENDOR] = NULL,
-};
-
+#if 0
static void gb_operation_request_handle(struct gb_operation *operation)
{
- u8 protocol = operation->connection->protocol;
+ struct gb_protocol *protocol = operation->connection->protocol;
+ struct gb_operation_msg_hdr *header;
- /* Subtract one from array size to stay within u8 range */
- if (protocol <= (u8)(ARRAY_SIZE(gb_operation_recv_handlers) - 1)) {
- gb_operation_recv_handler handler;
+ header = operation->request->header;
- handler = gb_operation_recv_handlers[protocol];
- if (handler) {
- handler(operation); /* Handle the request */
- return;
- }
+ /*
+ * If the protocol has no incoming request handler, report
+ * an error and mark the request bad.
+ */
+ if (protocol->request_recv) {
+ protocol->request_recv(header->type, operation);
+ return;
}
- gb_connection_err(operation->connection, "unrecognized protocol %u\n",
- (unsigned int)protocol);
- operation->result = GB_OP_PROTOCOL_BAD;
- gb_operation_complete(operation);
+ gb_connection_err(operation->connection,
+ "unexpected incoming request type 0x%02hhx\n", header->type);
+ operation->errno = -EPROTONOSUPPORT;
}
+#endif
/*
- * Either this operation contains an incoming request, or its
- * response has arrived. An incoming request will have a null
- * response buffer pointer (it is the responsibility of the request
- * handler to allocate and fill in the response buffer).
+ * Complete an operation in non-atomic context. The operation's
+ * result value should have been set before queueing this.
*/
-static void gb_operation_recv_work(struct work_struct *recv_work)
+static void gb_operation_work(struct work_struct *work)
{
struct gb_operation *operation;
- bool incoming_request;
- operation = container_of(recv_work, struct gb_operation, recv_work);
- incoming_request = operation->response == NULL;
- if (incoming_request)
- gb_operation_request_handle(operation);
+ operation = container_of(work, struct gb_operation, work);
gb_operation_complete(operation);
-
- /* We're finished with the buffer we read into */
- if (incoming_request)
- greybus_gbuf_finished(operation->request);
- else
- greybus_gbuf_finished(operation->response);
}
/*
- * Buffer completion function. We get notified whenever any buffer
- * completes. For outbound messages, this tells us that the message
- * has been sent. For inbound messages, it means the data has
- * landed in the buffer and is ready to be processed.
+ * Timeout call for the operation.
*
- * Either way, we don't do anything. We don't really care when an
- * outbound message has been sent, and for incoming messages we
- * we'll be done with everything we need to do before we mark it
- * finished.
- *
- * XXX We may want to record that a buffer is (or is no longer) in flight.
+ * If this fires, something went wrong, so mark the result as timed out, and
+ * run the completion handler, which (hopefully) should clean up the operation
+ * properly.
*/
-static void gb_operation_gbuf_complete(struct gbuf *gbuf)
+static void operation_timeout(struct work_struct *work)
{
- return;
+ struct gb_operation *operation;
+
+ operation = container_of(work, struct gb_operation, timeout_work.work);
+ pr_debug("%s: timeout!\n", __func__);
+
+ operation->errno = -ETIMEDOUT;
+ gb_operation_complete(operation);
}
/*
- * Allocate a buffer to be used for an operation request or response
- * message. For outgoing messages, both types of message contain a
+ * Given a pointer to the header in a message sent on a given host
+ * device, return the associated message structure. (This "header"
+ * is just the buffer pointer we supply to the host device for
+ * sending.)
+ */
+static struct gb_message *
+gb_hd_message_find(struct greybus_host_device *hd, void *header)
+{
+ struct gb_message *message;
+ u8 *result;
+
+ result = (u8 *)header - hd->buffer_headroom - sizeof(*message);
+ message = (struct gb_message *)result;
+
+ return message;
+}
+
+/*
+ * Allocate a message to be used for an operation request or
+ * response. For outgoing messages, both types of message contain a
* common header, which is filled in here. Incoming requests or
* responses also contain the same header, but there's no need to
* initialize it here (it'll be overwritten by the incoming
* message).
+ *
+ * Our message structure consists of:
+ * message structure
+ * headroom
+ * message header \_ these combined are
+ * message payload / the message size
*/
-struct gbuf *gb_operation_gbuf_create(struct gb_operation *operation,
- u8 type, size_t size, bool data_out)
+static struct gb_message *
+gb_operation_message_alloc(struct greybus_host_device *hd, u8 type,
+ size_t payload_size, gfp_t gfp_flags)
{
- struct gb_connection *connection = operation->connection;
+ struct gb_message *message;
struct gb_operation_msg_hdr *header;
- struct gbuf *gbuf;
- gfp_t gfp_flags = data_out ? GFP_KERNEL : GFP_ATOMIC;
+ size_t message_size = payload_size + sizeof(*header);
+ size_t size;
+ u8 *buffer;
+
+ if (message_size > hd->buffer_size_max)
+ return NULL;
- size += sizeof(*header);
- gbuf = greybus_alloc_gbuf(connection, gb_operation_gbuf_complete,
- size, data_out, gfp_flags, operation);
- if (!gbuf)
+ size = sizeof(*message) + hd->buffer_headroom + message_size;
+ message = kzalloc(size, gfp_flags);
+ if (!message)
return NULL;
+ buffer = &message->buffer[0];
+ header = (struct gb_operation_msg_hdr *)(buffer + hd->buffer_headroom);
/* Fill in the header structure */
- header = (struct gb_operation_msg_hdr *)gbuf->transfer_buffer;
- header->size = cpu_to_le16(size);
- header->id = 0; /* Filled in when submitted */
+ header->size = cpu_to_le16(message_size);
+ header->operation_id = 0; /* Filled in when submitted */
header->type = type;
- return gbuf;
+ message->header = header;
+ message->payload = header + 1;
+ message->size = message_size;
+
+ return message;
+}
+
+static void gb_operation_message_free(struct gb_message *message)
+{
+ kfree(message);
+}
+
+/*
+ * Map an enum gb_operation_status value (which is represented in a
+ * message as a single byte) to an appropriate Linux negative errno.
+ */
+int gb_operation_status_map(u8 status)
+{
+ switch (status) {
+ case GB_OP_SUCCESS:
+ return 0;
+ case GB_OP_INVALID:
+ return -EINVAL;
+ case GB_OP_NO_MEMORY:
+ return -ENOMEM;
+ case GB_OP_INTERRUPTED:
+ return -EINTR;
+ case GB_OP_RETRY:
+ return -EAGAIN;
+ case GB_OP_PROTOCOL_BAD:
+ return -EPROTONOSUPPORT;
+ case GB_OP_OVERFLOW:
+ return -E2BIG;
+ case GB_OP_TIMEOUT:
+ return -ETIMEDOUT;
+ default:
+ return -EIO;
+ }
}
/*
* Create a Greybus operation to be sent over the given connection.
- * The request buffer will big enough for a payload of the given
+ * The request buffer will be big enough for a payload of the given
* size. Outgoing requests must specify the size of the response
* buffer size, which must be sufficient to hold all expected
* response data.
* Returns a pointer to the new operation or a null pointer if an
* error occurs.
*/
-struct gb_operation *gb_operation_create(struct gb_connection *connection,
- u8 type, size_t request_size,
- size_t response_size)
+static struct gb_operation *
+gb_operation_create_common(struct gb_connection *connection, bool outgoing,
+ u8 type, size_t request_size,
+ size_t response_size)
{
+ struct greybus_host_device *hd = connection->hd;
struct gb_operation *operation;
gfp_t gfp_flags = response_size ? GFP_KERNEL : GFP_ATOMIC;
- bool outgoing = response_size != 0;
- /* XXX Use a slab cache */
- operation = kzalloc(sizeof(*operation), gfp_flags);
+ operation = kmem_cache_zalloc(gb_operation_cache, gfp_flags);
if (!operation)
return NULL;
- operation->connection = connection; /* XXX refcount? */
+ operation->connection = connection;
- operation->request = gb_operation_gbuf_create(operation, type,
- request_size,
- outgoing);
- if (!operation->request) {
- kfree(operation);
- return NULL;
- }
- operation->request_payload = operation->request->transfer_buffer +
- sizeof(struct gb_operation_msg_hdr);
- /* We always use the full request buffer */
- operation->request->actual_length = request_size;
+ operation->request = gb_operation_message_alloc(hd, type, request_size,
+ gfp_flags);
+ if (!operation->request)
+ goto err_cache;
+ operation->request->operation = operation;
if (outgoing) {
type |= GB_OPERATION_TYPE_RESPONSE;
- operation->response = gb_operation_gbuf_create(operation,
- type, response_size,
- false);
- if (!operation->response) {
- greybus_free_gbuf(operation->request);
- kfree(operation);
- return NULL;
- }
- operation->response_payload =
- operation->response->transfer_buffer +
- sizeof(struct gb_operation_msg_hdr);
+ operation->response = gb_operation_message_alloc(hd, type,
+ response_size, GFP_KERNEL);
+ if (!operation->response)
+ goto err_request;
+ operation->response->operation = operation;
}
- INIT_WORK(&operation->recv_work, gb_operation_recv_work);
+ INIT_WORK(&operation->work, gb_operation_work);
operation->callback = NULL; /* set at submit time */
init_completion(&operation->completion);
+ INIT_DELAYED_WORK(&operation->timeout_work, operation_timeout);
+ kref_init(&operation->kref);
spin_lock_irq(&gb_operations_lock);
list_add_tail(&operation->links, &connection->operations);
spin_unlock_irq(&gb_operations_lock);
return operation;
+
+err_request:
+ gb_operation_message_free(operation->request);
+err_cache:
+ kmem_cache_free(gb_operation_cache, operation);
+
+ return NULL;
+}
+
+struct gb_operation *gb_operation_create(struct gb_connection *connection,
+ u8 type, size_t request_size,
+ size_t response_size)
+{
+ return gb_operation_create_common(connection, true, type,
+ request_size, response_size);
+}
+
+static struct gb_operation *
+gb_operation_create_incoming(struct gb_connection *connection,
+ u8 type, size_t request_size,
+ size_t response_size)
+{
+ return gb_operation_create_common(connection, false, type,
+ request_size, response_size);
+}
+
+/*
+ * Get an additional reference on an operation.
+ */
+void gb_operation_get(struct gb_operation *operation)
+{
+ kref_get(&operation->kref);
}
/*
* Destroy a previously created operation.
*/
-void gb_operation_destroy(struct gb_operation *operation)
+static void _gb_operation_destroy(struct kref *kref)
{
- if (WARN_ON(!operation))
- return;
+ struct gb_operation *operation;
+
+ operation = container_of(kref, struct gb_operation, kref);
/* XXX Make sure it's not in flight */
spin_lock_irq(&gb_operations_lock);
list_del(&operation->links);
spin_unlock_irq(&gb_operations_lock);
- greybus_free_gbuf(operation->response);
- greybus_free_gbuf(operation->request);
+ gb_operation_message_free(operation->response);
+ gb_operation_message_free(operation->request);
+
+ kmem_cache_free(gb_operation_cache, operation);
+}
- kfree(operation);
+/*
+ * Drop a reference on an operation, and destroy it when the last
+ * one is gone.
+ */
+void gb_operation_put(struct gb_operation *operation)
+{
+ if (!WARN_ON(!operation))
+ kref_put(&operation->kref, _gb_operation_destroy);
}
/*
int gb_operation_request_send(struct gb_operation *operation,
gb_operation_callback callback)
{
+ unsigned long timeout;
int ret;
+ if (operation->connection->state != GB_CONNECTION_STATE_ENABLED)
+ return -ENOTCONN;
+
/*
- * XXX
- * I think the order of operations is going to be
- * significant, and if so, we may need a mutex to surround
- * setting the operation id and submitting the gbuf.
+ * First, get an extra reference on the operation.
+ * It'll be dropped when the operation completes.
*/
+ gb_operation_get(operation);
+
operation->callback = callback;
- gb_operation_insert(operation);
- ret = greybus_submit_gbuf(operation->request, GFP_KERNEL);
- if (ret)
+ gb_pending_operation_insert(operation);
+
+ /*
+ * We impose a time limit for requests to complete. We need
+ * to set the timer before we send the request though, so we
+ * don't lose a race with the receipt of the resposne.
+ */
+ timeout = msecs_to_jiffies(OPERATION_TIMEOUT_DEFAULT);
+ schedule_delayed_work(&operation->timeout_work, timeout);
+
+ /* All set, send the request */
+ ret = gb_message_send(operation->request, GFP_KERNEL);
+ if (ret || callback)
return ret;
- if (!callback)
- ret = gb_operation_wait(operation);
- return ret;
+ return gb_operation_wait(operation);
}
/*
*/
int gb_operation_response_send(struct gb_operation *operation)
{
- /* XXX
- * Caller needs to have set operation->response->actual_length
- */
- gb_operation_remove(operation);
gb_operation_destroy(operation);
return 0;
}
/*
- * Handle data arriving on a connection. This is called in
- * interrupt context, so just copy the incoming data into a buffer
- * and do remaining handling via a work queue.
+ * This function is called when a buffer send request has completed.
+ * The "header" is the message header--the beginning of what we
+ * asked to have sent.
*/
-void gb_connection_operation_recv(struct gb_connection *connection,
- void *data, size_t size)
+void
+greybus_data_sent(struct greybus_host_device *hd, void *header, int status)
+{
+ struct gb_message *message;
+ struct gb_operation *operation;
+
+ /* If there's no error, there's really nothing to do */
+ if (!status)
+ return; /* Mark it complete? */
+
+ /* XXX Right now we assume we're an outgoing request */
+ message = gb_hd_message_find(hd, header);
+ operation = message->operation;
+ operation->errno = status;
+ queue_work(gb_operation_workqueue, &operation->work);
+}
+EXPORT_SYMBOL_GPL(greybus_data_sent);
+
+/*
+ * We've received data on a connection, and it doesn't look like a
+ * response, so we assume it's a request.
+ *
+ * This is called in interrupt context, so just copy the incoming
+ * data into the request buffer and handle the rest via workqueue.
+ */
+void gb_connection_recv_request(struct gb_connection *connection,
+ u16 operation_id, u8 type, void *data, size_t size)
{
- struct gb_operation_msg_hdr *header;
struct gb_operation *operation;
- struct gbuf *gbuf;
- u16 msg_size;
- if (size > GB_OPERATION_MESSAGE_SIZE_MAX) {
- gb_connection_err(connection, "message too big");
+ operation = gb_operation_create_incoming(connection, type, size, 0);
+ if (!operation) {
+ gb_connection_err(connection, "can't create operation");
+ return; /* XXX Respond with pre-allocated ENOMEM */
+ }
+ operation->id = operation_id;
+ memcpy(operation->request->header, data, size);
+
+ /* XXX Right now this will just complete the operation */
+ operation->errno = -ENOSYS;
+ queue_work(gb_operation_workqueue, &operation->work);
+}
+
+/*
+ * We've received data that appears to be an operation response
+ * message. Look up the operation, and record that we've received
+ * its response.
+ *
+ * This is called in interrupt context, so just copy the incoming
+ * data into the response buffer and handle the rest via workqueue.
+ */
+static void gb_connection_recv_response(struct gb_connection *connection,
+ u16 operation_id, void *data, size_t size)
+{
+ struct gb_operation *operation;
+ struct gb_message *message;
+ struct gb_operation_msg_hdr *header;
+ int result;
+
+ operation = gb_pending_operation_find(connection, operation_id);
+ if (!operation) {
+ gb_connection_err(connection, "operation not found");
return;
}
- header = data;
- msg_size = le16_to_cpu(header->size);
- if (header->type & GB_OPERATION_TYPE_RESPONSE) {
- u16 id = le16_to_cpu(header->id);
-
- operation = gb_operation_find(connection, id);
- if (!operation) {
- gb_connection_err(connection, "operation not found");
- return;
- }
- gb_operation_remove(operation);
- gbuf = operation->response;
- if (size > gbuf->transfer_buffer_length) {
- gb_connection_err(connection, "recv buffer too small");
- return;
- }
+ cancel_delayed_work(&operation->timeout_work);
+ gb_pending_operation_remove(operation);
+
+ message = operation->response;
+ if (size <= message->size) {
+ /* Transfer the operation result from the response header */
+ header = message->header;
+ result = gb_operation_status_map(header->result);
} else {
- WARN_ON(msg_size != size);
- operation = gb_operation_create(connection, header->type,
- msg_size, 0);
- if (!operation) {
- gb_connection_err(connection, "can't create operation");
- return;
- }
- gbuf = operation->request;
+ gb_connection_err(connection, "recv buffer too small");
+ result = -E2BIG;
}
- memcpy(gbuf->transfer_buffer, data, msg_size);
- gbuf->actual_length = msg_size;
+ /* We must ignore the payload if a bad status is returned */
+ if (!result)
+ memcpy(message->header, data, size);
/* The rest will be handled in work queue context */
- queue_work(gb_operation_recv_workqueue, &operation->recv_work);
+ operation->errno = result;
+ queue_work(gb_operation_workqueue, &operation->work);
+}
+
+/*
+ * Handle data arriving on a connection. As soon as we return the
+ * supplied data buffer will be reused (so unless we do something
+ * with, it's effectively dropped).
+ */
+void gb_connection_recv(struct gb_connection *connection,
+ void *data, size_t size)
+{
+ struct gb_operation_msg_hdr *header;
+ size_t msg_size;
+ u16 operation_id;
+
+ if (connection->state != GB_CONNECTION_STATE_ENABLED) {
+ gb_connection_err(connection, "dropping %zu received bytes",
+ size);
+ return;
+ }
+
+ if (size < sizeof(*header)) {
+ gb_connection_err(connection, "message too small");
+ return;
+ }
+
+ header = data;
+ msg_size = (size_t)le16_to_cpu(header->size);
+ if (msg_size > size) {
+ gb_connection_err(connection, "incomplete message");
+ return; /* XXX Should still complete operation */
+ }
+
+ operation_id = le16_to_cpu(header->operation_id);
+ if (header->type & GB_OPERATION_TYPE_RESPONSE)
+ gb_connection_recv_response(connection, operation_id,
+ data, msg_size);
+ else
+ gb_connection_recv_request(connection, operation_id,
+ header->type, data, msg_size);
+}
+
+/*
+ * Cancel an operation.
+ */
+void gb_operation_cancel(struct gb_operation *operation)
+{
+ operation->canceled = true;
+ gb_message_cancel(operation->request);
+ gb_message_cancel(operation->response);
}
int gb_operation_init(void)
{
- gb_operation_recv_workqueue = alloc_workqueue("greybus_recv", 0, 1);
- if (!gb_operation_recv_workqueue)
+ gb_operation_cache = kmem_cache_create("gb_operation_cache",
+ sizeof(struct gb_operation), 0, 0, NULL);
+ if (!gb_operation_cache)
return -ENOMEM;
+ gb_operation_workqueue = alloc_workqueue("greybus_operation", 0, 1);
+ if (!gb_operation_workqueue) {
+ kmem_cache_destroy(gb_operation_cache);
+ gb_operation_cache = NULL;
+ return -ENOMEM;
+ }
+
return 0;
}
void gb_operation_exit(void)
{
- destroy_workqueue(gb_operation_recv_workqueue);
+ destroy_workqueue(gb_operation_workqueue);
+ gb_operation_workqueue = NULL;
+ kmem_cache_destroy(gb_operation_cache);
+ gb_operation_cache = NULL;
}
projects / cascardo / linux.git / blobdiff