firewire: cdev: add ioctls for manual iso resource management
This adds ioctls for allocation and deallocation of a channel or/and
bandwidth without auto-reallocation and without auto-deallocation.
The benefit of these ioctls is that libraw1394-style isochronous
resource management can be implemented without write access to the IRM's
character device file.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-cdev.c b/drivers/firewire/fw-cdev.c
index a227853..08fe68d 100644
--- a/drivers/firewire/fw-cdev.c
+++ b/drivers/firewire/fw-cdev.c
@@ -121,14 +121,15 @@
struct client *client;
/* Schedule work and access todo only with client->lock held. */
struct delayed_work work;
- enum {ISO_RES_ALLOC, ISO_RES_REALLOC, ISO_RES_DEALLOC,} todo;
+ enum {ISO_RES_ALLOC, ISO_RES_REALLOC, ISO_RES_DEALLOC,
+ ISO_RES_ALLOC_ONCE, ISO_RES_DEALLOC_ONCE,} todo;
int generation;
u64 channels;
s32 bandwidth;
struct iso_resource_event *e_alloc, *e_dealloc;
};
-static void schedule_iso_resource(struct iso_resource *);
+static int schedule_iso_resource(struct iso_resource *);
static void release_iso_resource(struct client *, struct client_resource *);
/*
@@ -1033,7 +1034,9 @@
skip = todo == ISO_RES_REALLOC &&
r->generation == generation;
}
- free = todo == ISO_RES_DEALLOC;
+ free = todo == ISO_RES_DEALLOC ||
+ todo == ISO_RES_ALLOC_ONCE ||
+ todo == ISO_RES_DEALLOC_ONCE;
r->generation = generation;
spin_unlock_irq(&client->lock);
@@ -1044,7 +1047,9 @@
fw_iso_resource_manage(client->device->card, generation,
r->channels, &channel, &bandwidth,
- todo == ISO_RES_ALLOC || todo == ISO_RES_REALLOC);
+ todo == ISO_RES_ALLOC ||
+ todo == ISO_RES_REALLOC ||
+ todo == ISO_RES_ALLOC_ONCE);
/*
* Is this generation outdated already? As long as this resource sticks
* in the idr, it will be scheduled again for a newer generation or at
@@ -1082,7 +1087,7 @@
if (todo == ISO_RES_REALLOC && success)
goto out;
- if (todo == ISO_RES_ALLOC) {
+ if (todo == ISO_RES_ALLOC || todo == ISO_RES_ALLOC_ONCE) {
e = r->e_alloc;
r->e_alloc = NULL;
} else {
@@ -1106,10 +1111,17 @@
client_put(client);
}
-static void schedule_iso_resource(struct iso_resource *r)
+static int schedule_iso_resource(struct iso_resource *r)
{
- if (schedule_delayed_work(&r->work, 0))
- client_get(r->client);
+ int scheduled;
+
+ client_get(r->client);
+
+ scheduled = schedule_delayed_work(&r->work, 0);
+ if (!scheduled)
+ client_put(r->client);
+
+ return scheduled;
}
static void release_iso_resource(struct client *client,
@@ -1124,9 +1136,9 @@
spin_unlock_irq(&client->lock);
}
-static int ioctl_allocate_iso_resource(struct client *client, void *buffer)
+static int init_iso_resource(struct client *client,
+ struct fw_cdev_allocate_iso_resource *request, int todo)
{
- struct fw_cdev_allocate_iso_resource *request = buffer;
struct iso_resource_event *e1, *e2;
struct iso_resource *r;
int ret;
@@ -1146,7 +1158,7 @@
INIT_DELAYED_WORK(&r->work, iso_resource_work);
r->client = client;
- r->todo = ISO_RES_ALLOC;
+ r->todo = todo;
r->generation = -1;
r->channels = request->channels;
r->bandwidth = request->bandwidth;
@@ -1158,8 +1170,14 @@
e2->resource.closure = request->closure;
e2->resource.type = FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED;
- r->resource.release = release_iso_resource;
- ret = add_client_resource(client, &r->resource, GFP_KERNEL);
+ if (todo == ISO_RES_ALLOC) {
+ r->resource.release = release_iso_resource;
+ ret = add_client_resource(client, &r->resource, GFP_KERNEL);
+ } else {
+ r->resource.release = NULL;
+ r->resource.handle = -1;
+ ret = schedule_iso_resource(r) ? 0 : -ENOMEM;
+ }
if (ret < 0)
goto fail;
request->handle = r->resource.handle;
@@ -1173,6 +1191,13 @@
return ret;
}
+static int ioctl_allocate_iso_resource(struct client *client, void *buffer)
+{
+ struct fw_cdev_allocate_iso_resource *request = buffer;
+
+ return init_iso_resource(client, request, ISO_RES_ALLOC);
+}
+
static int ioctl_deallocate_iso_resource(struct client *client, void *buffer)
{
struct fw_cdev_deallocate *request = buffer;
@@ -1181,6 +1206,20 @@
release_iso_resource, NULL);
}
+static int ioctl_allocate_iso_resource_once(struct client *client, void *buffer)
+{
+ struct fw_cdev_allocate_iso_resource *request = buffer;
+
+ return init_iso_resource(client, request, ISO_RES_ALLOC_ONCE);
+}
+
+static int ioctl_deallocate_iso_resource_once(struct client *client, void *buffer)
+{
+ struct fw_cdev_allocate_iso_resource *request = buffer;
+
+ return init_iso_resource(client, request, ISO_RES_DEALLOC_ONCE);
+}
+
static int (* const ioctl_handlers[])(struct client *client, void *buffer) = {
ioctl_get_info,
ioctl_send_request,
@@ -1197,6 +1236,8 @@
ioctl_get_cycle_timer,
ioctl_allocate_iso_resource,
ioctl_deallocate_iso_resource,
+ ioctl_allocate_iso_resource_once,
+ ioctl_deallocate_iso_resource_once,
};
static int dispatch_ioctl(struct client *client,