#include <linux/module.h>
#include <linux/kernel.h>
+#include <linux/kref.h>
#include <linux/wait.h>
#include <linux/errno.h>
#include <linux/device.h>
unsigned long vm_start;
struct list_head link;
+ struct kref kref;
};
-static inline void __user *
-u64_to_uptr(__u64 value)
+static inline void client_get(struct client *client)
+{
+ kref_get(&client->kref);
+}
+
+static void client_release(struct kref *kref)
+{
+ struct client *client = container_of(kref, struct client, kref);
+
+ fw_device_put(client->device);
+ kfree(client);
+}
+
+static void client_put(struct client *client)
+{
+ kref_put(&client->kref, client_release);
+}
+
+static inline void __user *u64_to_uptr(__u64 value)
{
return (void __user *)(unsigned long)value;
}
-static inline __u64
-uptr_to_u64(void __user *ptr)
+static inline __u64 uptr_to_u64(void __user *ptr)
{
return (__u64)(unsigned long)ptr;
}
idr_init(&client->resource_idr);
INIT_LIST_HEAD(&client->event_list);
init_waitqueue_head(&client->wait);
+ kref_init(&client->kref);
file->private_data = client;
wake_up_interruptible(&client->wait);
}
-static int
-dequeue_event(struct client *client, char __user *buffer, size_t count)
+static int dequeue_event(struct client *client,
+ char __user *buffer, size_t count)
{
unsigned long flags;
struct event *event;
size_t size, total;
- int i, retval;
+ int i, ret;
- retval = wait_event_interruptible(client->wait,
- !list_empty(&client->event_list) ||
- fw_device_is_shutdown(client->device));
- if (retval < 0)
- return retval;
+ ret = wait_event_interruptible(client->wait,
+ !list_empty(&client->event_list) ||
+ fw_device_is_shutdown(client->device));
+ if (ret < 0)
+ return ret;
if (list_empty(&client->event_list) &&
fw_device_is_shutdown(client->device))
return -ENODEV;
spin_lock_irqsave(&client->lock, flags);
- event = container_of(client->event_list.next, struct event, link);
+ event = list_first_entry(&client->event_list, struct event, link);
list_del(&event->link);
spin_unlock_irqrestore(&client->lock, flags);
for (i = 0; i < ARRAY_SIZE(event->v) && total < count; i++) {
size = min(event->v[i].size, count - total);
if (copy_to_user(buffer + total, event->v[i].data, size)) {
- retval = -EFAULT;
+ ret = -EFAULT;
goto out;
}
total += size;
}
- retval = total;
+ ret = total;
out:
kfree(event);
- return retval;
+ return ret;
}
-static ssize_t
-fw_device_op_read(struct file *file,
- char __user *buffer, size_t count, loff_t *offset)
+static ssize_t fw_device_op_read(struct file *file, char __user *buffer,
+ size_t count, loff_t *offset)
{
struct client *client = file->private_data;
return dequeue_event(client, buffer, count);
}
-static void
-fill_bus_reset_event(struct fw_cdev_event_bus_reset *event,
- struct client *client)
+static void fill_bus_reset_event(struct fw_cdev_event_bus_reset *event,
+ struct client *client)
{
struct fw_card *card = client->device->card;
unsigned long flags;
spin_unlock_irqrestore(&card->lock, flags);
}
-static void
-for_each_client(struct fw_device *device,
- void (*callback)(struct client *client))
+static void for_each_client(struct fw_device *device,
+ void (*callback)(struct client *client))
{
struct client *c;
mutex_unlock(&device->client_list_mutex);
}
-static void
-queue_bus_reset_event(struct client *client)
+static void queue_bus_reset_event(struct client *client)
{
struct bus_reset *bus_reset;
return 0;
}
-static int
-add_client_resource(struct client *client, struct client_resource *resource,
- gfp_t gfp_mask)
+static int add_client_resource(struct client *client,
+ struct client_resource *resource, gfp_t gfp_mask)
{
unsigned long flags;
int ret;
else
ret = idr_get_new(&client->resource_idr, resource,
&resource->handle);
+ if (ret >= 0)
+ client_get(client);
spin_unlock_irqrestore(&client->lock, flags);
if (ret == -EAGAIN)
return ret < 0 ? ret : 0;
}
-static int
-release_client_resource(struct client *client, u32 handle,
- client_resource_release_fn_t release,
- struct client_resource **resource)
+static int release_client_resource(struct client *client, u32 handle,
+ client_resource_release_fn_t release,
+ struct client_resource **resource)
{
struct client_resource *r;
unsigned long flags;
else
r->release(client, r);
+ client_put(client);
+
return 0;
}
-static void
-release_transaction(struct client *client, struct client_resource *resource)
+static void release_transaction(struct client *client,
+ struct client_resource *resource)
{
struct response *response =
container_of(resource, struct response, resource);
fw_cancel_transaction(client->device->card, &response->transaction);
}
-static void
-complete_transaction(struct fw_card *card, int rcode,
- void *payload, size_t length, void *data)
+static void complete_transaction(struct fw_card *card, int rcode,
+ void *payload, size_t length, void *data)
{
struct response *response = data;
struct client *client = response->client;
spin_lock_irqsave(&client->lock, flags);
/*
- * If called while in shutdown, the idr tree must be left untouched.
- * The idr handle will be removed later.
+ * 1. If called while in shutdown, the idr tree must be left untouched.
+ * The idr handle will be removed and the client reference will be
+ * dropped later.
+ * 2. If the call chain was release_client_resource ->
+ * release_transaction -> complete_transaction (instead of a normal
+ * conclusion of the transaction), i.e. if this resource was already
+ * unregistered from the idr, the client reference will be dropped
+ * by release_client_resource and we must not drop it here.
*/
- if (!client->in_shutdown)
+ if (!client->in_shutdown &&
+ idr_find(&client->resource_idr, response->resource.handle)) {
idr_remove(&client->resource_idr, response->resource.handle);
+ /* Drop the idr's reference */
+ client_put(client);
+ }
spin_unlock_irqrestore(&client->lock, flags);
r->type = FW_CDEV_EVENT_RESPONSE;
else
queue_event(client, &response->event, r, sizeof(*r) + r->length,
NULL, 0);
+
+ /* Drop the transaction callback's reference */
+ client_put(client);
}
static int ioctl_send_request(struct client *client, void *buffer)
if (ret < 0)
goto failed;
+ /* Get a reference for the transaction callback */
+ client_get(client);
+
fw_send_request(device->card, &response->transaction,
request->tcode & 0x1f,
device->node->node_id,
struct fw_cdev_event_request request;
};
-static void
-release_request(struct client *client, struct client_resource *resource)
+static void release_request(struct client *client,
+ struct client_resource *resource)
{
struct request *request =
container_of(resource, struct request, resource);
kfree(request);
}
-static void
-handle_request(struct fw_card *card, struct fw_request *r,
- int tcode, int destination, int source,
- int generation, int speed,
- unsigned long long offset,
- void *payload, size_t length, void *callback_data)
+static void handle_request(struct fw_card *card, struct fw_request *r,
+ int tcode, int destination, int source,
+ int generation, int speed,
+ unsigned long long offset,
+ void *payload, size_t length, void *callback_data)
{
struct address_handler *handler = callback_data;
struct request *request;
fw_send_response(card, r, RCODE_CONFLICT_ERROR);
}
-static void
-release_address_handler(struct client *client,
- struct client_resource *resource)
+static void release_address_handler(struct client *client,
+ struct client_resource *resource)
{
struct address_handler *handler =
container_of(resource, struct address_handler, resource);
handler->closure = request->closure;
handler->client = client;
- if (fw_core_add_address_handler(&handler->handler, ®ion) < 0) {
+ ret = fw_core_add_address_handler(&handler->handler, ®ion);
+ if (ret < 0) {
kfree(handler);
- return -EBUSY;
+ return ret;
}
handler->resource.release = release_address_handler;
release_descriptor, NULL);
}
-static void
-iso_callback(struct fw_iso_context *context, u32 cycle,
- size_t header_length, void *header, void *data)
+static void iso_callback(struct fw_iso_context *context, u32 cycle,
+ size_t header_length, void *header, void *data)
{
struct client *client = data;
struct iso_interrupt *irq;
ioctl_get_cycle_timer,
};
-static int
-dispatch_ioctl(struct client *client, unsigned int cmd, void __user *arg)
+static int dispatch_ioctl(struct client *client,
+ unsigned int cmd, void __user *arg)
{
char buffer[256];
- int retval;
+ int ret;
if (_IOC_TYPE(cmd) != '#' ||
_IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers))
return -EFAULT;
}
- retval = ioctl_handlers[_IOC_NR(cmd)](client, buffer);
- if (retval < 0)
- return retval;
+ ret = ioctl_handlers[_IOC_NR(cmd)](client, buffer);
+ if (ret < 0)
+ return ret;
if (_IOC_DIR(cmd) & _IOC_READ) {
if (_IOC_SIZE(cmd) > sizeof(buffer) ||
return -EFAULT;
}
- return retval;
+ return ret;
}
-static long
-fw_device_op_ioctl(struct file *file,
- unsigned int cmd, unsigned long arg)
+static long fw_device_op_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
{
struct client *client = file->private_data;
}
#ifdef CONFIG_COMPAT
-static long
-fw_device_op_compat_ioctl(struct file *file,
- unsigned int cmd, unsigned long arg)
+static long fw_device_op_compat_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
{
struct client *client = file->private_data;
struct client *client = file->private_data;
enum dma_data_direction direction;
unsigned long size;
- int page_count, retval;
+ int page_count, ret;
if (fw_device_is_shutdown(client->device))
return -ENODEV;
else
direction = DMA_FROM_DEVICE;
- retval = fw_iso_buffer_init(&client->buffer, client->device->card,
- page_count, direction);
- if (retval < 0)
- return retval;
+ ret = fw_iso_buffer_init(&client->buffer, client->device->card,
+ page_count, direction);
+ if (ret < 0)
+ return ret;
- retval = fw_iso_buffer_map(&client->buffer, vma);
- if (retval < 0)
+ ret = fw_iso_buffer_map(&client->buffer, vma);
+ if (ret < 0)
fw_iso_buffer_destroy(&client->buffer, client->device->card);
- return retval;
+ return ret;
}
static int shutdown_resource(int id, void *p, void *data)
struct client *client = data;
r->release(client, r);
+ client_put(client);
return 0;
}
list_for_each_entry_safe(e, next_e, &client->event_list, link)
kfree(e);
- /*
- * FIXME: client should be reference-counted. It's extremely unlikely
- * but there may still be transactions being completed at this point.
- */
- fw_device_put(client->device);
- kfree(client);
+ client_put(client);
return 0;
}
projects / cascardo / linux.git / blobdiff