firewire: cdev: add closure to async stream ioctl

This changes the as yet unreleased FW_CDEV_IOC_SEND_STREAM_PACKET ioctl
to generate an fw_cdev_event_response event just like the other two
ioctls for asynchronous request transmission do.  This way, clients get
feedback on successful or unsuccessful transmission.

This also adds input validation for length, tag, channel, sy, speed.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

3 files changed, 40 insertions, 57 deletions

diff --git a/drivers/firewire/fw-cdev.c b/drivers/firewire/fw-cdev.c
index 95a207545eb..7eb6594cc3e 100644
--- a/drivers/firewire/fw-cdev.c
+++ b/drivers/firewire/fw-cdev.c
@@ -522,7 +522,8 @@ static int init_request(struct client *client,
         struct outbound_transaction_event *e;
         int ret;
 
-        if (request->length > 4096 || request->length > 512 << speed)
+        if (request->tcode != TCODE_STREAM_DATA &&
+            (request->length > 4096 || request->length > 512 << speed))
                 return -EIO;
 
         e = kmalloc(sizeof(*e) + request->length, GFP_KERNEL);
@@ -1247,36 +1248,27 @@ static int ioctl_send_broadcast_request(struct client *client, void *buffer)
         return init_request(client, request, LOCAL_BUS | 0x3f, SCODE_100);
 }
 
-struct stream_packet {
-        struct fw_packet packet;
-        u8 data[0];
-};
-
-static void send_stream_packet_done(struct fw_packet *packet,
-                                    struct fw_card *card, int status)
-{
-        kfree(container_of(packet, struct stream_packet, packet));
-}
-
 static int ioctl_send_stream_packet(struct client *client, void *buffer)
 {
-        struct fw_cdev_send_stream_packet *request = buffer;
-        struct stream_packet *p;
+        struct fw_cdev_send_stream_packet *p = buffer;
+        struct fw_cdev_send_request request;
+        int dest;
 
-        p = kmalloc(sizeof(*p) + request->size, GFP_KERNEL);
-        if (p == NULL)
-                return -ENOMEM;
+        if (p->speed > client->device->card->link_speed ||
+            p->length > 1024 << p->speed)
+                return -EIO;
 
-        if (request->data &&
-            copy_from_user(p->data, u64_to_uptr(request->data), request->size)) {
-                kfree(p);
-                return -EFAULT;
-        }
-        fw_send_stream_packet(client->device->card, &p->packet,
-                              request->generation, request->speed,
-                              request->channel, request->sy, request->tag,
-                              p->data, request->size, send_stream_packet_done);
-        return 0;
+        if (p->tag > 3 || p->channel > 63 || p->sy > 15)
+                return -EINVAL;
+
+        dest = fw_stream_packet_destination_id(p->tag, p->channel, p->sy);
+        request.tcode           = TCODE_STREAM_DATA;
+        request.length          = p->length;
+        request.closure         = p->closure;
+        request.data            = p->data;
+        request.generation      = p->generation;
+
+        return init_request(client, &request, dest, p->speed);
 }
 
 static int (* const ioctl_handlers[])(struct client *client, void *buffer) = {
diff --git a/drivers/firewire/fw-transaction.c b/drivers/firewire/fw-transaction.c
index e3da5899196..4a9b37461c2 100644
--- a/drivers/firewire/fw-transaction.c
+++ b/drivers/firewire/fw-transaction.c
@@ -37,10 +37,6 @@
 #include "fw-topology.h"
 #include "fw-device.h"
 
-#define HEADER_TAG(tag)                 ((tag) << 14)
-#define HEADER_CHANNEL(ch)              ((ch) << 8)
-#define HEADER_SY(sy)                   ((sy) << 0)
-
 #define HEADER_PRI(pri)                 ((pri) << 0)
 #define HEADER_TCODE(tcode)             ((tcode) << 4)
 #define HEADER_RETRY(retry)             ((retry) << 8)
@@ -158,6 +154,18 @@ static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
 {
         int ext_tcode;
 
+        if (tcode == TCODE_STREAM_DATA) {
+                packet->header[0] =
+                        HEADER_DATA_LENGTH(length) |
+                        destination_id |
+                        HEADER_TCODE(TCODE_STREAM_DATA);
+                packet->header_length = 4;
+                packet->payload = payload;
+                packet->payload_length = length;
+
+                goto common;
+        }
+
         if (tcode > 0x10) {
                 ext_tcode = tcode & ~0x10;
                 tcode = TCODE_LOCK_REQUEST;
@@ -204,7 +212,7 @@ static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
                 packet->payload_length = 0;
                 break;
         }
-
+ common:
         packet->speed = speed;
         packet->generation = generation;
         packet->ack = 0;
@@ -246,6 +254,9 @@ static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
  * @param callback function to be called when the transaction is completed
  * @param callback_data pointer to arbitrary data, which will be
  *   passed to the callback
+ *
+ * In case of asynchronous stream packets i.e. TCODE_STREAM_DATA, the caller
+ * needs to synthesize @destination_id with fw_stream_packet_destination_id().
  */
 void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
                      int destination_id, int generation, int speed,
@@ -297,27 +308,6 @@ void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
 }
 EXPORT_SYMBOL(fw_send_request);
 
-void fw_send_stream_packet(struct fw_card *card, struct fw_packet *p,
-                int generation, int speed, int channel, int sy, int tag,
-                void *payload, size_t length, fw_packet_callback_t callback)
-{
-        p->callback = callback;
-        p->header[0] =
-                  HEADER_DATA_LENGTH(length)
-                | HEADER_TAG(tag)
-                | HEADER_CHANNEL(channel)
-                | HEADER_TCODE(TCODE_STREAM_DATA)
-                | HEADER_SY(sy);
-        p->header_length = 4;
-        p->payload = payload;
-        p->payload_length = length;
-        p->speed = speed;
-        p->generation = generation;
-        p->ack = 0;
-
-        card->driver->send_request(card, p);
-}
-
 struct transaction_callback_data {
         struct completion done;
         void *payload;
diff --git a/drivers/firewire/fw-transaction.h b/drivers/firewire/fw-transaction.h
index f90f09c0583..d4f42cecbdf 100644
--- a/drivers/firewire/fw-transaction.h
+++ b/drivers/firewire/fw-transaction.h
@@ -412,10 +412,6 @@ void fw_send_request(struct fw_card *card, struct fw_transaction *t,
                 int tcode, int destination_id, int generation, int speed,
                 unsigned long long offset, void *payload, size_t length,
                 fw_transaction_callback_t callback, void *callback_data);
-void fw_send_stream_packet(struct fw_card *card, struct fw_packet *p,
-                int generation, int speed, int channel, int sy, int tag,
-                void *payload, size_t length, fw_packet_callback_t callback);
-
 int fw_cancel_transaction(struct fw_card *card,
                           struct fw_transaction *transaction);
 void fw_flush_transactions(struct fw_card *card);
@@ -425,6 +421,11 @@ int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
 void fw_send_phy_config(struct fw_card *card,
                         int node_id, int generation, int gap_count);
 
+static inline int fw_stream_packet_destination_id(int tag, int channel, int sy)
+{
+        return tag << 14 | channel << 8 | sy;
+}
+
 /*
  * Called by the topology code to inform the device code of node
  * activity; found, lost, or updated nodes.