#include <linux/mutex.h>
#include <linux/jiffies.h>
#include <linux/rculist.h>
+#include <linux/idr.h>
static DEFINE_MUTEX(dma_list_mutex);
static LIST_HEAD(dma_device_list);
static long dmaengine_ref_count;
+static struct idr dma_idr;
/* --- sysfs implementation --- */
struct dma_chan_dev *chan_dev;
chan_dev = container_of(dev, typeof(*chan_dev), device);
+ if (atomic_dec_and_test(chan_dev->idr_ref)) {
+ mutex_lock(&dma_list_mutex);
+ idr_remove(&dma_idr, chan_dev->dev_id);
+ mutex_unlock(&dma_list_mutex);
+ kfree(chan_dev->idr_ref);
+ }
kfree(chan_dev);
}
return err;
}
-subsys_initcall(dma_channel_table_init);
+arch_initcall(dma_channel_table_init);
/**
* dma_find_channel - find a channel to carry out the operation
struct dma_chan *chan;
int cpu;
- WARN_ONCE(dmaengine_ref_count == 0,
- "client called %s without a reference", __func__);
-
cpu = get_cpu();
chan = per_cpu_ptr(channel_table[tx_type], cpu)->chan;
put_cpu();
struct dma_device *device;
struct dma_chan *chan;
- WARN_ONCE(dmaengine_ref_count == 0,
- "client called %s without a reference", __func__);
-
rcu_read_lock();
list_for_each_entry_rcu(device, &dma_device_list, global_node) {
if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
}
}
-static struct dma_chan *private_candidate(dma_cap_mask_t *mask, struct dma_device *dev)
+static struct dma_chan *private_candidate(dma_cap_mask_t *mask, struct dma_device *dev,
+ dma_filter_fn fn, void *fn_param)
{
struct dma_chan *chan;
- struct dma_chan *ret = NULL;
if (!__dma_device_satisfies_mask(dev, mask)) {
pr_debug("%s: wrong capabilities\n", __func__);
__func__, dma_chan_name(chan));
continue;
}
- ret = chan;
- break;
+ if (fn && !fn(chan, fn_param)) {
+ pr_debug("%s: %s filter said false\n",
+ __func__, dma_chan_name(chan));
+ continue;
+ }
+ return chan;
}
- return ret;
+ return NULL;
}
/**
{
struct dma_device *device, *_d;
struct dma_chan *chan = NULL;
- bool ack;
int err;
/* Find a channel */
mutex_lock(&dma_list_mutex);
list_for_each_entry_safe(device, _d, &dma_device_list, global_node) {
- chan = private_candidate(mask, device);
- if (!chan)
- continue;
-
- if (fn)
- ack = fn(chan, fn_param);
- else
- ack = true;
-
- if (ack) {
+ chan = private_candidate(mask, device, fn, fn_param);
+ if (chan) {
/* Found a suitable channel, try to grab, prep, and
* return it. We first set DMA_PRIVATE to disable
* balance_ref_count as this channel will not be
* published in the general-purpose allocator
*/
dma_cap_set(DMA_PRIVATE, device->cap_mask);
+ device->privatecnt++;
err = dma_chan_get(chan);
if (err == -ENODEV) {
dma_chan_name(chan), err);
else
break;
- } else
- pr_debug("%s: %s filter said false\n",
- __func__, dma_chan_name(chan));
- chan = NULL;
+ if (--device->privatecnt == 0)
+ dma_cap_clear(DMA_PRIVATE, device->cap_mask);
+ chan->private = NULL;
+ chan = NULL;
+ }
}
mutex_unlock(&dma_list_mutex);
WARN_ONCE(chan->client_count != 1,
"chan reference count %d != 1\n", chan->client_count);
dma_chan_put(chan);
+ /* drop PRIVATE cap enabled by __dma_request_channel() */
+ if (--chan->device->privatecnt == 0)
+ dma_cap_clear(DMA_PRIVATE, chan->device->cap_mask);
+ chan->private = NULL;
mutex_unlock(&dma_list_mutex);
}
EXPORT_SYMBOL_GPL(dma_release_channel);
}
EXPORT_SYMBOL(dmaengine_put);
+static bool device_has_all_tx_types(struct dma_device *device)
+{
+ /* A device that satisfies this test has channels that will never cause
+ * an async_tx channel switch event as all possible operation types can
+ * be handled.
+ */
+ #ifdef CONFIG_ASYNC_TX_DMA
+ if (!dma_has_cap(DMA_INTERRUPT, device->cap_mask))
+ return false;
+ #endif
+
+ #if defined(CONFIG_ASYNC_MEMCPY) || defined(CONFIG_ASYNC_MEMCPY_MODULE)
+ if (!dma_has_cap(DMA_MEMCPY, device->cap_mask))
+ return false;
+ #endif
+
+ #if defined(CONFIG_ASYNC_MEMSET) || defined(CONFIG_ASYNC_MEMSET_MODULE)
+ if (!dma_has_cap(DMA_MEMSET, device->cap_mask))
+ return false;
+ #endif
+
+ #if defined(CONFIG_ASYNC_XOR) || defined(CONFIG_ASYNC_XOR_MODULE)
+ if (!dma_has_cap(DMA_XOR, device->cap_mask))
+ return false;
+
+ #ifndef CONFIG_ASYNC_TX_DISABLE_XOR_VAL_DMA
+ if (!dma_has_cap(DMA_XOR_VAL, device->cap_mask))
+ return false;
+ #endif
+ #endif
+
+ #if defined(CONFIG_ASYNC_PQ) || defined(CONFIG_ASYNC_PQ_MODULE)
+ if (!dma_has_cap(DMA_PQ, device->cap_mask))
+ return false;
+
+ #ifndef CONFIG_ASYNC_TX_DISABLE_PQ_VAL_DMA
+ if (!dma_has_cap(DMA_PQ_VAL, device->cap_mask))
+ return false;
+ #endif
+ #endif
+
+ return true;
+}
+
+static int get_dma_id(struct dma_device *device)
+{
+ int rc;
+
+ idr_retry:
+ if (!idr_pre_get(&dma_idr, GFP_KERNEL))
+ return -ENOMEM;
+ mutex_lock(&dma_list_mutex);
+ rc = idr_get_new(&dma_idr, NULL, &device->dev_id);
+ mutex_unlock(&dma_list_mutex);
+ if (rc == -EAGAIN)
+ goto idr_retry;
+ else if (rc != 0)
+ return rc;
+
+ return 0;
+}
+
/**
* dma_async_device_register - registers DMA devices found
* @device: &dma_device
*/
int dma_async_device_register(struct dma_device *device)
{
- static int id;
int chancnt = 0, rc;
struct dma_chan* chan;
+ atomic_t *idr_ref;
if (!device)
return -ENODEV;
!device->device_prep_dma_memcpy);
BUG_ON(dma_has_cap(DMA_XOR, device->cap_mask) &&
!device->device_prep_dma_xor);
- BUG_ON(dma_has_cap(DMA_ZERO_SUM, device->cap_mask) &&
- !device->device_prep_dma_zero_sum);
+ BUG_ON(dma_has_cap(DMA_XOR_VAL, device->cap_mask) &&
+ !device->device_prep_dma_xor_val);
+ BUG_ON(dma_has_cap(DMA_PQ, device->cap_mask) &&
+ !device->device_prep_dma_pq);
+ BUG_ON(dma_has_cap(DMA_PQ_VAL, device->cap_mask) &&
+ !device->device_prep_dma_pq_val);
BUG_ON(dma_has_cap(DMA_MEMSET, device->cap_mask) &&
!device->device_prep_dma_memset);
BUG_ON(dma_has_cap(DMA_INTERRUPT, device->cap_mask) &&
BUG_ON(!device->device_issue_pending);
BUG_ON(!device->dev);
- mutex_lock(&dma_list_mutex);
- device->dev_id = id++;
- mutex_unlock(&dma_list_mutex);
+ /* note: this only matters in the
+ * CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH=y case
+ */
+ if (device_has_all_tx_types(device))
+ dma_cap_set(DMA_ASYNC_TX, device->cap_mask);
+
+ idr_ref = kmalloc(sizeof(*idr_ref), GFP_KERNEL);
+ if (!idr_ref)
+ return -ENOMEM;
+ rc = get_dma_id(device);
+ if (rc != 0) {
+ kfree(idr_ref);
+ return rc;
+ }
+
+ atomic_set(idr_ref, 0);
/* represent channels in sysfs. Probably want devs too */
list_for_each_entry(chan, &device->channels, device_node) {
+ rc = -ENOMEM;
chan->local = alloc_percpu(typeof(*chan->local));
if (chan->local == NULL)
- continue;
+ goto err_out;
chan->dev = kzalloc(sizeof(*chan->dev), GFP_KERNEL);
if (chan->dev == NULL) {
free_percpu(chan->local);
- continue;
+ chan->local = NULL;
+ goto err_out;
}
chan->chan_id = chancnt++;
chan->dev->device.class = &dma_devclass;
chan->dev->device.parent = device->dev;
chan->dev->chan = chan;
+ chan->dev->idr_ref = idr_ref;
+ chan->dev->dev_id = device->dev_id;
+ atomic_inc(idr_ref);
dev_set_name(&chan->dev->device, "dma%dchan%d",
device->dev_id, chan->chan_id);
if (rc) {
free_percpu(chan->local);
chan->local = NULL;
+ kfree(chan->dev);
+ atomic_dec(idr_ref);
goto err_out;
}
chan->client_count = 0;
}
}
list_add_tail_rcu(&device->global_node, &dma_device_list);
+ if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
+ device->privatecnt++; /* Always private */
dma_channel_rebalance();
mutex_unlock(&dma_list_mutex);
return 0;
err_out:
+ /* if we never registered a channel just release the idr */
+ if (atomic_read(idr_ref) == 0) {
+ mutex_lock(&dma_list_mutex);
+ idr_remove(&dma_idr, device->dev_id);
+ mutex_unlock(&dma_list_mutex);
+ kfree(idr_ref);
+ return rc;
+ }
+
list_for_each_entry(chan, &device->channels, device_node) {
if (chan->local == NULL)
continue;
dma_addr_t dma_dest, dma_src;
dma_cookie_t cookie;
int cpu;
+ unsigned long flags;
dma_src = dma_map_single(dev->dev, src, len, DMA_TO_DEVICE);
dma_dest = dma_map_single(dev->dev, dest, len, DMA_FROM_DEVICE);
- tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
- DMA_CTRL_ACK);
+ flags = DMA_CTRL_ACK |
+ DMA_COMPL_SRC_UNMAP_SINGLE |
+ DMA_COMPL_DEST_UNMAP_SINGLE;
+ tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len, flags);
if (!tx) {
dma_unmap_single(dev->dev, dma_src, len, DMA_TO_DEVICE);
dma_addr_t dma_dest, dma_src;
dma_cookie_t cookie;
int cpu;
+ unsigned long flags;
dma_src = dma_map_single(dev->dev, kdata, len, DMA_TO_DEVICE);
dma_dest = dma_map_page(dev->dev, page, offset, len, DMA_FROM_DEVICE);
- tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
- DMA_CTRL_ACK);
+ flags = DMA_CTRL_ACK | DMA_COMPL_SRC_UNMAP_SINGLE;
+ tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len, flags);
if (!tx) {
dma_unmap_single(dev->dev, dma_src, len, DMA_TO_DEVICE);
dma_addr_t dma_dest, dma_src;
dma_cookie_t cookie;
int cpu;
+ unsigned long flags;
dma_src = dma_map_page(dev->dev, src_pg, src_off, len, DMA_TO_DEVICE);
dma_dest = dma_map_page(dev->dev, dest_pg, dest_off, len,
DMA_FROM_DEVICE);
- tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
- DMA_CTRL_ACK);
+ flags = DMA_CTRL_ACK;
+ tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len, flags);
if (!tx) {
dma_unmap_page(dev->dev, dma_src, len, DMA_TO_DEVICE);
/* dma_wait_for_async_tx - spin wait for a transaction to complete
* @tx: in-flight transaction to wait on
- *
- * This routine assumes that tx was obtained from a call to async_memcpy,
- * async_xor, async_memset, etc which ensures that tx is "in-flight" (prepped
- * and submitted). Walking the parent chain is only meant to cover for DMA
- * drivers that do not implement the DMA_INTERRUPT capability and may race with
- * the driver's descriptor cleanup routine.
*/
enum dma_status
dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
{
- enum dma_status status;
- struct dma_async_tx_descriptor *iter;
- struct dma_async_tx_descriptor *parent;
+ unsigned long dma_sync_wait_timeout = jiffies + msecs_to_jiffies(5000);
if (!tx)
return DMA_SUCCESS;
- WARN_ONCE(tx->parent, "%s: speculatively walking dependency chain for"
- " %s\n", __func__, dma_chan_name(tx->chan));
-
- /* poll through the dependency chain, return when tx is complete */
- do {
- iter = tx;
-
- /* find the root of the unsubmitted dependency chain */
- do {
- parent = iter->parent;
- if (!parent)
- break;
- else
- iter = parent;
- } while (parent);
-
- /* there is a small window for ->parent == NULL and
- * ->cookie == -EBUSY
- */
- while (iter->cookie == -EBUSY)
- cpu_relax();
-
- status = dma_sync_wait(iter->chan, iter->cookie);
- } while (status == DMA_IN_PROGRESS || (iter != tx));
-
- return status;
+ while (tx->cookie == -EBUSY) {
+ if (time_after_eq(jiffies, dma_sync_wait_timeout)) {
+ pr_err("%s timeout waiting for descriptor submission\n",
+ __func__);
+ return DMA_ERROR;
+ }
+ cpu_relax();
+ }
+ return dma_sync_wait(tx->chan, tx->cookie);
}
EXPORT_SYMBOL_GPL(dma_wait_for_async_tx);
if (!dep)
return;
+ /* we'll submit tx->next now, so clear the link */
+ tx->next = NULL;
chan = dep->chan;
/* keep submitting up until a channel switch is detected
static int __init dma_bus_init(void)
{
+ idr_init(&dma_idr);
mutex_init(&dma_list_mutex);
return class_register(&dma_devclass);
}
-subsys_initcall(dma_bus_init);
+arch_initcall(dma_bus_init);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff