*
* LOCKING:
*
- * The subsystem keeps two global lists, dma_device_list and dma_client_list.
- * Both of these are protected by a mutex, dma_list_mutex.
+ * The subsystem keeps a global list of dma_device structs it is protected by a
+ * mutex, dma_list_mutex.
*
* Each device has a channels list, which runs unlocked but is never modified
* once the device is registered, it's just setup by the driver.
*
- * Each client is responsible for keeping track of the channels it uses. See
- * the definition of dma_event_callback in dmaengine.h.
- *
* Each device has a kref, which is initialized to 1 when the device is
* registered. A kref_get is done for each device registered. When the
* device is released, the corresponding kref_put is done in the release
static DEFINE_MUTEX(dma_list_mutex);
static LIST_HEAD(dma_device_list);
-static LIST_HEAD(dma_client_list);
static long dmaengine_ref_count;
/* --- sysfs implementation --- */
/* allocate upon first client reference */
if (chan->client_count == 1 && err == 0) {
- int desc_cnt = chan->device->device_alloc_chan_resources(chan, NULL);
+ int desc_cnt = chan->device->device_alloc_chan_resources(chan);
if (desc_cnt < 0) {
err = desc_cnt;
chan->device->device_free_chan_resources(chan);
}
-/**
- * dma_client_chan_alloc - try to allocate channels to a client
- * @client: &dma_client
- *
- * Called with dma_list_mutex held.
- */
-static void dma_client_chan_alloc(struct dma_client *client)
-{
- struct dma_device *device;
- struct dma_chan *chan;
- enum dma_state_client ack;
-
- /* Find a channel */
- list_for_each_entry(device, &dma_device_list, global_node) {
- if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
- continue;
- if (!dma_device_satisfies_mask(device, client->cap_mask))
- continue;
-
- list_for_each_entry(chan, &device->channels, device_node) {
- if (!chan->client_count)
- continue;
- ack = client->event_callback(client, chan,
- DMA_RESOURCE_AVAILABLE);
-
- /* we are done once this client rejects
- * an available resource
- */
- if (ack == DMA_NAK)
- return;
- }
- }
-}
-
enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
{
enum dma_status status;
EXPORT_SYMBOL_GPL(dma_release_channel);
/**
- * dma_chans_notify_available - broadcast available channels to the clients
- */
-static void dma_clients_notify_available(void)
-{
- struct dma_client *client;
-
- mutex_lock(&dma_list_mutex);
-
- list_for_each_entry(client, &dma_client_list, global_node)
- dma_client_chan_alloc(client);
-
- mutex_unlock(&dma_list_mutex);
-}
-
-/**
* dmaengine_get - register interest in dma_channels
*/
void dmaengine_get(void)
EXPORT_SYMBOL(dmaengine_put);
/**
- * dma_async_client_chan_request - send all available channels to the
- * client that satisfy the capability mask
- * @client - requester
- */
-void dma_async_client_chan_request(struct dma_client *client)
-{
- mutex_lock(&dma_list_mutex);
- dma_client_chan_alloc(client);
- mutex_unlock(&dma_list_mutex);
-}
-EXPORT_SYMBOL(dma_async_client_chan_request);
-
-/**
* dma_async_device_register - registers DMA devices found
* @device: &dma_device
*/
dma_channel_rebalance();
mutex_unlock(&dma_list_mutex);
- dma_clients_notify_available();
-
return 0;
err_out:
spin_unlock_bh(&dwc->lock);
}
-static int dwc_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int dwc_alloc_chan_resources(struct dma_chan *chan)
{
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
struct dw_dma *dw = to_dw_dma(chan->device);
*
* Return - The number of descriptors allocated.
*/
-static int fsl_dma_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int fsl_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
* ioat_dma_alloc_chan_resources - returns the number of allocated descriptors
* @chan: the channel to be filled out
*/
-static int ioat_dma_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int ioat_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
struct ioat_desc_sw *desc;
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (device->common.device_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (device->common.device_alloc_chan_resources(dma_chan) < 1) {
dev_err(&device->pdev->dev,
"selftest cannot allocate chan resource\n");
err = -ENODEV;
* greater than 2x the number slots needed to satisfy a device->max_xor
* request.
* */
-static int iop_adma_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int iop_adma_alloc_chan_resources(struct dma_chan *chan)
{
char *hw_desc;
int idx;
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (iop_adma_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
err = -ENODEV;
goto out;
}
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (iop_adma_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
err = -ENODEV;
goto out;
}
}
/* returns the number of allocated descriptors */
-static int mv_xor_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int mv_xor_alloc_chan_resources(struct dma_chan *chan)
{
char *hw_desc;
int idx;
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (mv_xor_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (mv_xor_alloc_chan_resources(dma_chan) < 1) {
err = -ENODEV;
goto out;
}
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (mv_xor_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (mv_xor_alloc_chan_resources(dma_chan) < 1) {
err = -ENODEV;
goto out;
}
struct atmel_mci_dma {
#ifdef CONFIG_MMC_ATMELMCI_DMA
- struct dma_client client;
struct dma_chan *chan;
struct dma_async_tx_descriptor *data_desc;
#endif
#include <linux/dma-mapping.h>
/**
- * enum dma_state - resource PNP/power management state
- * @DMA_RESOURCE_SUSPEND: DMA device going into low power state
- * @DMA_RESOURCE_RESUME: DMA device returning to full power
- * @DMA_RESOURCE_AVAILABLE: DMA device available to the system
- * @DMA_RESOURCE_REMOVED: DMA device removed from the system
- */
-enum dma_state {
- DMA_RESOURCE_SUSPEND,
- DMA_RESOURCE_RESUME,
- DMA_RESOURCE_AVAILABLE,
- DMA_RESOURCE_REMOVED,
-};
-
-/**
* enum dma_state_client - state of the channel in the client
* @DMA_ACK: client would like to use, or was using this channel
* @DMA_DUP: client has already seen this channel, or is not using this channel
void dma_chan_cleanup(struct kref *kref);
-/*
- * typedef dma_event_callback - function pointer to a DMA event callback
- * For each channel added to the system this routine is called for each client.
- * If the client would like to use the channel it returns '1' to signal (ack)
- * the dmaengine core to take out a reference on the channel and its
- * corresponding device. A client must not 'ack' an available channel more
- * than once. When a channel is removed all clients are notified. If a client
- * is using the channel it must 'ack' the removal. A client must not 'ack' a
- * removed channel more than once.
- * @client - 'this' pointer for the client context
- * @chan - channel to be acted upon
- * @state - available or removed
- */
-struct dma_client;
-typedef enum dma_state_client (*dma_event_callback) (struct dma_client *client,
- struct dma_chan *chan, enum dma_state state);
-
/**
* typedef dma_filter_fn - callback filter for dma_request_channel
* @chan: channel to be reviewed
*/
typedef enum dma_state_client (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
-/**
- * struct dma_client - info on the entity making use of DMA services
- * @event_callback: func ptr to call when something happens
- * @cap_mask: only return channels that satisfy the requested capabilities
- * a value of zero corresponds to any capability
- * @slave: data for preparing slave transfer. Must be non-NULL iff the
- * DMA_SLAVE capability is requested.
- * @global_node: list_head for global dma_client_list
- */
-struct dma_client {
- dma_event_callback event_callback;
- dma_cap_mask_t cap_mask;
- struct list_head global_node;
-};
-
typedef void (*dma_async_tx_callback)(void *dma_async_param);
/**
* struct dma_async_tx_descriptor - async transaction descriptor
int dev_id;
struct device *dev;
- int (*device_alloc_chan_resources)(struct dma_chan *chan,
- struct dma_client *client);
+ int (*device_alloc_chan_resources)(struct dma_chan *chan);
void (*device_free_chan_resources)(struct dma_chan *chan);
struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(
void dmaengine_get(void);
void dmaengine_put(void);
-void dma_async_client_chan_request(struct dma_client *client);
dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan,
void *dest, void *src, size_t len);
dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan,
static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
static struct list_head ptype_all __read_mostly; /* Taps */
-#ifdef CONFIG_NET_DMA
-struct net_dma {
- struct dma_client client;
- spinlock_t lock;
- cpumask_t channel_mask;
- struct dma_chan **channels;
-};
-
-static enum dma_state_client
-netdev_dma_event(struct dma_client *client, struct dma_chan *chan,
- enum dma_state state);
-
-static struct net_dma net_dma = {
- .client = {
- .event_callback = netdev_dma_event,
- },
-};
-#endif
-
/*
* The @dev_base_head list is protected by @dev_base_lock and the rtnl
* semaphore.
return NOTIFY_OK;
}
-#ifdef CONFIG_NET_DMA
-/**
- * netdev_dma_event - event callback for the net_dma_client
- * @client: should always be net_dma_client
- * @chan: DMA channel for the event
- * @state: DMA state to be handled
- */
-static enum dma_state_client
-netdev_dma_event(struct dma_client *client, struct dma_chan *chan,
- enum dma_state state)
-{
- int i, found = 0, pos = -1;
- struct net_dma *net_dma =
- container_of(client, struct net_dma, client);
- enum dma_state_client ack = DMA_DUP; /* default: take no action */
-
- spin_lock(&net_dma->lock);
- switch (state) {
- case DMA_RESOURCE_AVAILABLE:
- for (i = 0; i < nr_cpu_ids; i++)
- if (net_dma->channels[i] == chan) {
- found = 1;
- break;
- } else if (net_dma->channels[i] == NULL && pos < 0)
- pos = i;
-
- if (!found && pos >= 0) {
- ack = DMA_ACK;
- net_dma->channels[pos] = chan;
- cpu_set(pos, net_dma->channel_mask);
- }
- break;
- case DMA_RESOURCE_REMOVED:
- for (i = 0; i < nr_cpu_ids; i++)
- if (net_dma->channels[i] == chan) {
- found = 1;
- pos = i;
- break;
- }
-
- if (found) {
- ack = DMA_ACK;
- cpu_clear(pos, net_dma->channel_mask);
- net_dma->channels[i] = NULL;
- }
- break;
- default:
- break;
- }
- spin_unlock(&net_dma->lock);
-
- return ack;
-}
-
-/**
- * netdev_dma_register - register the networking subsystem as a DMA client
- */
-static int __init netdev_dma_register(void)
-{
- net_dma.channels = kzalloc(nr_cpu_ids * sizeof(struct net_dma),
- GFP_KERNEL);
- if (unlikely(!net_dma.channels)) {
- printk(KERN_NOTICE
- "netdev_dma: no memory for net_dma.channels\n");
- return -ENOMEM;
- }
- spin_lock_init(&net_dma.lock);
- dma_cap_set(DMA_MEMCPY, net_dma.client.cap_mask);
- dmaengine_get();
- return 0;
-}
-
-#else
-static int __init netdev_dma_register(void) { return -ENODEV; }
-#endif /* CONFIG_NET_DMA */
/**
* netdev_increment_features - increment feature set by one
if (register_pernet_device(&default_device_ops))
goto out;
- netdev_dma_register();
-
open_softirq(NET_TX_SOFTIRQ, net_tx_action);
open_softirq(NET_RX_SOFTIRQ, net_rx_action);
hotcpu_notifier(dev_cpu_callback, 0);
dst_init();
dev_mcast_init();
+ #ifdef CONFIG_NET_DMA
+ dmaengine_get();
+ #endif
rc = 0;
out:
return rc;
git://ftp.safe.ca / safe / jmp / linux-2.6 / commitdiff