1 files changed, 56 insertions, 38 deletions

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 5a87384ea4ff..bd0b248de2cf 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -608,6 +608,40 @@ void dmaengine_put(void)
 }
 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;
+        #endif
+
+        #if defined(CONFIG_ASYNC_PQ) || defined(CONFIG_ASYNC_PQ_MODULE)
+        if (!dma_has_cap(DMA_PQ, device->cap_mask))
+                return false;
+        #endif
+
+        return true;
+}
+
 static int get_dma_id(struct dma_device *device)
 {
         int rc;
@@ -644,8 +678,12 @@ int dma_async_device_register(struct dma_device *device)
                 !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) &&
@@ -661,6 +699,12 @@ int dma_async_device_register(struct dma_device *device)
         BUG_ON(!device->device_issue_pending);
         BUG_ON(!device->dev);
 
+        /* 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;
@@ -933,55 +977,29 @@ void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
 {
         tx->chan = chan;
         spin_lock_init(&tx->lock);
-        INIT_LIST_HEAD(&tx->tx_list);
 }
 EXPORT_SYMBOL(dma_async_tx_descriptor_init);
 
 /* 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);