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-rw-r--r--crypto/async_tx/async_tx.c350
1 files changed, 5 insertions, 345 deletions
diff --git a/crypto/async_tx/async_tx.c b/crypto/async_tx/async_tx.c
index dcbf1be..f21147f 100644
--- a/crypto/async_tx/async_tx.c
+++ b/crypto/async_tx/async_tx.c
@@ -28,351 +28,18 @@
#include <linux/async_tx.h>
#ifdef CONFIG_DMA_ENGINE
-static enum dma_state_client
-dma_channel_add_remove(struct dma_client *client,
- struct dma_chan *chan, enum dma_state state);
-
-static struct dma_client async_tx_dma = {
- .event_callback = dma_channel_add_remove,
- /* .cap_mask == 0 defaults to all channels */
-};
-
-/**
- * dma_cap_mask_all - enable iteration over all operation types
- */
-static dma_cap_mask_t dma_cap_mask_all;
-
-/**
- * chan_ref_percpu - tracks channel allocations per core/opertion
- */
-struct chan_ref_percpu {
- struct dma_chan_ref *ref;
-};
-
-static int channel_table_initialized;
-static struct chan_ref_percpu *channel_table[DMA_TX_TYPE_END];
-
-/**
- * async_tx_lock - protect modification of async_tx_master_list and serialize
- * rebalance operations
- */
-static spinlock_t async_tx_lock;
-
-static LIST_HEAD(async_tx_master_list);
-
-/* async_tx_issue_pending_all - start all transactions on all channels */
-void async_tx_issue_pending_all(void)
-{
- struct dma_chan_ref *ref;
-
- rcu_read_lock();
- list_for_each_entry_rcu(ref, &async_tx_master_list, node)
- ref->chan->device->device_issue_pending(ref->chan);
- rcu_read_unlock();
-}
-EXPORT_SYMBOL_GPL(async_tx_issue_pending_all);
-
-/* dma_wait_for_async_tx - spin wait for a transcation to complete
- * @tx: transaction to wait on
- */
-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;
-
- if (!tx)
- return DMA_SUCCESS;
-
- /* 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;
-}
-EXPORT_SYMBOL_GPL(dma_wait_for_async_tx);
-
-/* async_tx_run_dependencies - helper routine for dma drivers to process
- * (start) dependent operations on their target channel
- * @tx: transaction with dependencies
- */
-void async_tx_run_dependencies(struct dma_async_tx_descriptor *tx)
-{
- struct dma_async_tx_descriptor *dep = tx->next;
- struct dma_async_tx_descriptor *dep_next;
- struct dma_chan *chan;
-
- if (!dep)
- return;
-
- chan = dep->chan;
-
- /* keep submitting up until a channel switch is detected
- * in that case we will be called again as a result of
- * processing the interrupt from async_tx_channel_switch
- */
- for (; dep; dep = dep_next) {
- spin_lock_bh(&dep->lock);
- dep->parent = NULL;
- dep_next = dep->next;
- if (dep_next && dep_next->chan == chan)
- dep->next = NULL; /* ->next will be submitted */
- else
- dep_next = NULL; /* submit current dep and terminate */
- spin_unlock_bh(&dep->lock);
-
- dep->tx_submit(dep);
- }
-
- chan->device->device_issue_pending(chan);
-}
-EXPORT_SYMBOL_GPL(async_tx_run_dependencies);
-
-static void
-free_dma_chan_ref(struct rcu_head *rcu)
-{
- struct dma_chan_ref *ref;
- ref = container_of(rcu, struct dma_chan_ref, rcu);
- kfree(ref);
-}
-
-static void
-init_dma_chan_ref(struct dma_chan_ref *ref, struct dma_chan *chan)
-{
- INIT_LIST_HEAD(&ref->node);
- INIT_RCU_HEAD(&ref->rcu);
- ref->chan = chan;
- atomic_set(&ref->count, 0);
-}
-
-/**
- * get_chan_ref_by_cap - returns the nth channel of the given capability
- * defaults to returning the channel with the desired capability and the
- * lowest reference count if the index can not be satisfied
- * @cap: capability to match
- * @index: nth channel desired, passing -1 has the effect of forcing the
- * default return value
- */
-static struct dma_chan_ref *
-get_chan_ref_by_cap(enum dma_transaction_type cap, int index)
-{
- struct dma_chan_ref *ret_ref = NULL, *min_ref = NULL, *ref;
-
- rcu_read_lock();
- list_for_each_entry_rcu(ref, &async_tx_master_list, node)
- if (dma_has_cap(cap, ref->chan->device->cap_mask)) {
- if (!min_ref)
- min_ref = ref;
- else if (atomic_read(&ref->count) <
- atomic_read(&min_ref->count))
- min_ref = ref;
-
- if (index-- == 0) {
- ret_ref = ref;
- break;
- }
- }
- rcu_read_unlock();
-
- if (!ret_ref)
- ret_ref = min_ref;
-
- if (ret_ref)
- atomic_inc(&ret_ref->count);
-
- return ret_ref;
-}
-
-/**
- * async_tx_rebalance - redistribute the available channels, optimize
- * for cpu isolation in the SMP case, and opertaion isolation in the
- * uniprocessor case
- */
-static void async_tx_rebalance(void)
-{
- int cpu, cap, cpu_idx = 0;
- unsigned long flags;
-
- if (!channel_table_initialized)
- return;
-
- spin_lock_irqsave(&async_tx_lock, flags);
-
- /* undo the last distribution */
- for_each_dma_cap_mask(cap, dma_cap_mask_all)
- for_each_possible_cpu(cpu) {
- struct dma_chan_ref *ref =
- per_cpu_ptr(channel_table[cap], cpu)->ref;
- if (ref) {
- atomic_set(&ref->count, 0);
- per_cpu_ptr(channel_table[cap], cpu)->ref =
- NULL;
- }
- }
-
- for_each_dma_cap_mask(cap, dma_cap_mask_all)
- for_each_online_cpu(cpu) {
- struct dma_chan_ref *new;
- if (NR_CPUS > 1)
- new = get_chan_ref_by_cap(cap, cpu_idx++);
- else
- new = get_chan_ref_by_cap(cap, -1);
-
- per_cpu_ptr(channel_table[cap], cpu)->ref = new;
- }
-
- spin_unlock_irqrestore(&async_tx_lock, flags);
-}
-
-static enum dma_state_client
-dma_channel_add_remove(struct dma_client *client,
- struct dma_chan *chan, enum dma_state state)
-{
- unsigned long found, flags;
- struct dma_chan_ref *master_ref, *ref;
- enum dma_state_client ack = DMA_DUP; /* default: take no action */
-
- switch (state) {
- case DMA_RESOURCE_AVAILABLE:
- found = 0;
- rcu_read_lock();
- list_for_each_entry_rcu(ref, &async_tx_master_list, node)
- if (ref->chan == chan) {
- found = 1;
- break;
- }
- rcu_read_unlock();
-
- pr_debug("async_tx: dma resource available [%s]\n",
- found ? "old" : "new");
-
- if (!found)
- ack = DMA_ACK;
- else
- break;
-
- /* add the channel to the generic management list */
- master_ref = kmalloc(sizeof(*master_ref), GFP_KERNEL);
- if (master_ref) {
- /* keep a reference until async_tx is unloaded */
- dma_chan_get(chan);
- init_dma_chan_ref(master_ref, chan);
- spin_lock_irqsave(&async_tx_lock, flags);
- list_add_tail_rcu(&master_ref->node,
- &async_tx_master_list);
- spin_unlock_irqrestore(&async_tx_lock,
- flags);
- } else {
- printk(KERN_WARNING "async_tx: unable to create"
- " new master entry in response to"
- " a DMA_RESOURCE_ADDED event"
- " (-ENOMEM)\n");
- return 0;
- }
-
- async_tx_rebalance();
- break;
- case DMA_RESOURCE_REMOVED:
- found = 0;
- spin_lock_irqsave(&async_tx_lock, flags);
- list_for_each_entry(ref, &async_tx_master_list, node)
- if (ref->chan == chan) {
- /* permit backing devices to go away */
- dma_chan_put(ref->chan);
- list_del_rcu(&ref->node);
- call_rcu(&ref->rcu, free_dma_chan_ref);
- found = 1;
- break;
- }
- spin_unlock_irqrestore(&async_tx_lock, flags);
-
- pr_debug("async_tx: dma resource removed [%s]\n",
- found ? "ours" : "not ours");
-
- if (found)
- ack = DMA_ACK;
- else
- break;
-
- async_tx_rebalance();
- break;
- case DMA_RESOURCE_SUSPEND:
- case DMA_RESOURCE_RESUME:
- printk(KERN_WARNING "async_tx: does not support dma channel"
- " suspend/resume\n");
- break;
- default:
- BUG();
- }
-
- return ack;
-}
-
-static int __init
-async_tx_init(void)
+static int __init async_tx_init(void)
{
- enum dma_transaction_type cap;
-
- spin_lock_init(&async_tx_lock);
- bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END);
-
- /* an interrupt will never be an explicit operation type.
- * clearing this bit prevents allocation to a slot in 'channel_table'
- */
- clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits);
-
- for_each_dma_cap_mask(cap, dma_cap_mask_all) {
- channel_table[cap] = alloc_percpu(struct chan_ref_percpu);
- if (!channel_table[cap])
- goto err;
- }
-
- channel_table_initialized = 1;
- dma_async_client_register(&async_tx_dma);
- dma_async_client_chan_request(&async_tx_dma);
+ dmaengine_get();
printk(KERN_INFO "async_tx: api initialized (async)\n");
return 0;
-err:
- printk(KERN_ERR "async_tx: initialization failure\n");
-
- while (--cap >= 0)
- free_percpu(channel_table[cap]);
-
- return 1;
}
static void __exit async_tx_exit(void)
{
- enum dma_transaction_type cap;
-
- channel_table_initialized = 0;
-
- for_each_dma_cap_mask(cap, dma_cap_mask_all)
- if (channel_table[cap])
- free_percpu(channel_table[cap]);
-
- dma_async_client_unregister(&async_tx_dma);
+ dmaengine_put();
}
/**
@@ -387,16 +54,9 @@ __async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
{
/* see if we can keep the chain on one channel */
if (depend_tx &&
- dma_has_cap(tx_type, depend_tx->chan->device->cap_mask))
+ dma_has_cap(tx_type, depend_tx->chan->device->cap_mask))
return depend_tx->chan;
- else if (likely(channel_table_initialized)) {
- struct dma_chan_ref *ref;
- int cpu = get_cpu();
- ref = per_cpu_ptr(channel_table[tx_type], cpu)->ref;
- put_cpu();
- return ref ? ref->chan : NULL;
- } else
- return NULL;
+ return dma_find_channel(tx_type);
}
EXPORT_SYMBOL_GPL(__async_tx_find_channel);
#else