dmaengine: ack to flags: make use of the unused bits in the 'ack' field

'ack' is currently a simple integer that flags whether or not a client is done
touching fields in the given descriptor.  It is effectively just a single bit
of information.  Converting this to a flags parameter allows the other bits to
be put to use to control completion actions, like dma-unmap, and capture
results, like xor-zero-sum == 0.

Changes are one of:
1/ convert all open-coded ->ack manipulations to use async_tx_ack
   and async_tx_test_ack.
2/ set the ack bit at prep time where possible
3/ make drivers store the flags at prep time
4/ add flags to the device_prep_dma_interrupt prototype

Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

crypto/async_tx/async_memcpy.c

@@ -77,7 +77,7 @@ async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
 			/* if ack is already set then we cannot be sure
 			 * we are referring to the correct operation
 			 */
-			BUG_ON(depend_tx->ack);
+			BUG_ON(async_tx_test_ack(depend_tx));
 			if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
 				panic("%s: DMA_ERROR waiting for depend_tx\n",
 					__func__);

crypto/async_tx/async_tx.c

@@ -446,7 +446,7 @@ async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx,
 	 * otherwise poll for completion
 	 */
 	if (dma_has_cap(DMA_INTERRUPT, device->cap_mask))
-		intr_tx = device->device_prep_dma_interrupt(chan);
+		intr_tx = device->device_prep_dma_interrupt(chan, 0);
 	else
 		intr_tx = NULL;
 
@@ -515,7 +515,8 @@ async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
 		 * 2/ dependencies are 1:1 i.e. two transactions can
 		 * not depend on the same parent
 		 */
-		BUG_ON(depend_tx->ack || depend_tx->next || tx->parent);
+		BUG_ON(async_tx_test_ack(depend_tx) || depend_tx->next ||
+		       tx->parent);
 
 		/* the lock prevents async_tx_run_dependencies from missing
 		 * the setting of ->next when ->parent != NULL
@@ -594,7 +595,7 @@ async_trigger_callback(enum async_tx_flags flags,
 		if (device && !dma_has_cap(DMA_INTERRUPT, device->cap_mask))
 			device = NULL;
 
-		tx = device ? device->device_prep_dma_interrupt(chan) : NULL;
+		tx = device ? device->device_prep_dma_interrupt(chan, 0) : NULL;
 	} else
 		tx = NULL;
 
@@ -610,7 +611,7 @@ async_trigger_callback(enum async_tx_flags flags,
 			/* if ack is already set then we cannot be sure
 			 * we are referring to the correct operation
 			 */
-			BUG_ON(depend_tx->ack);
+			BUG_ON(async_tx_test_ack(depend_tx));
 			if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
 				panic("%s: DMA_ERROR waiting for depend_tx\n",
 					__func__);

crypto/async_tx/async_xor.c

@@ -191,7 +191,7 @@ async_xor(struct page *dest, struct page **src_list, unsigned int offset,
 				/* if ack is already set then we cannot be sure
 				 * we are referring to the correct operation
 				 */
-				BUG_ON(depend_tx->ack);
+				BUG_ON(async_tx_test_ack(depend_tx));
 				if (dma_wait_for_async_tx(depend_tx) ==
 					DMA_ERROR)
 					panic("%s: DMA_ERROR waiting for "

drivers/dma/dmaengine.c

@@ -478,15 +478,15 @@ dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest,
 
 	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, 0);
+	tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
+					 DMA_CTRL_ACK);
 
 	if (!tx) {
 		dma_unmap_single(dev->dev, dma_src, len, DMA_TO_DEVICE);
 		dma_unmap_single(dev->dev, dma_dest, len, DMA_FROM_DEVICE);
 		return -ENOMEM;
 	}
 
-	tx->ack = 1;
 	tx->callback = NULL;
 	cookie = tx->tx_submit(tx);
 
@@ -524,15 +524,15 @@ dma_async_memcpy_buf_to_pg(struct dma_chan *chan, struct page *page,
 
 	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, 0);
+	tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
+					 DMA_CTRL_ACK);
 
 	if (!tx) {
 		dma_unmap_single(dev->dev, dma_src, len, DMA_TO_DEVICE);
 		dma_unmap_page(dev->dev, dma_dest, len, DMA_FROM_DEVICE);
 		return -ENOMEM;
 	}
 
-	tx->ack = 1;
 	tx->callback = NULL;
 	cookie = tx->tx_submit(tx);
 
@@ -573,15 +573,15 @@ dma_async_memcpy_pg_to_pg(struct dma_chan *chan, struct page *dest_pg,
 	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, 0);
+	tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
+					 DMA_CTRL_ACK);
 
 	if (!tx) {
 		dma_unmap_page(dev->dev, dma_src, len, DMA_TO_DEVICE);
 		dma_unmap_page(dev->dev, dma_dest, len, DMA_FROM_DEVICE);
 		return -ENOMEM;
 	}
 
-	tx->ack = 1;
 	tx->callback = NULL;
 	cookie = tx->tx_submit(tx);
 

drivers/dma/fsldma.c

@@ -412,7 +412,7 @@ static void fsl_dma_free_chan_resources(struct dma_chan *chan)
 }
 
 static struct dma_async_tx_descriptor *
-fsl_dma_prep_interrupt(struct dma_chan *chan)
+fsl_dma_prep_interrupt(struct dma_chan *chan, unsigned long flags)
 {
 	struct fsl_dma_chan *fsl_chan;
 	struct fsl_desc_sw *new;
@@ -429,7 +429,7 @@ fsl_dma_prep_interrupt(struct dma_chan *chan)
 	}
 
 	new->async_tx.cookie = -EBUSY;
-	new->async_tx.ack = 0;
+	new->async_tx.flags = flags;
 
 	/* Insert the link descriptor to the LD ring */
 	list_add_tail(&new->node, &new->async_tx.tx_list);
@@ -482,7 +482,7 @@ static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
 			set_desc_next(fsl_chan, &prev->hw, new->async_tx.phys);
 
 		new->async_tx.cookie = 0;
-		new->async_tx.ack = 1;
+		async_tx_ack(&new->async_tx);
 
 		prev = new;
 		len -= copy;
@@ -493,7 +493,7 @@ static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
 		list_add_tail(&new->node, &first->async_tx.tx_list);
 	} while (len);
 
-	new->async_tx.ack = 0; /* client is in control of this ack */
+	new->async_tx.flags = flags; /* client is in control of this ack */
 	new->async_tx.cookie = -EBUSY;
 
 	/* Set End-of-link to the last link descriptor of new list*/
@@ -874,7 +874,7 @@ static int fsl_dma_self_test(struct fsl_dma_chan *fsl_chan)
 	async_tx_ack(tx3);
 
 	/* Interrupt tx test */
-	tx1 = fsl_dma_prep_interrupt(chan);
+	tx1 = fsl_dma_prep_interrupt(chan, 0);
 	async_tx_ack(tx1);
 	cookie = fsl_dma_tx_submit(tx1);
 

drivers/dma/ioat_dma.c

@@ -212,14 +212,14 @@ static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
 	u32 copy;
 	size_t len;
 	dma_addr_t src, dst;
-	int orig_ack;
+	unsigned long orig_flags;
 	unsigned int desc_count = 0;
 
 	/* src and dest and len are stored in the initial descriptor */
 	len = first->len;
 	src = first->src;
 	dst = first->dst;
-	orig_ack = first->async_tx.ack;
+	orig_flags = first->async_tx.flags;
 	new = first;
 
 	spin_lock_bh(&ioat_chan->desc_lock);
@@ -228,7 +228,7 @@ static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
 	do {
 		copy = min_t(size_t, len, ioat_chan->xfercap);
 
-		new->async_tx.ack = 1;
+		async_tx_ack(&new->async_tx);
 
 		hw = new->hw;
 		hw->size = copy;
@@ -264,7 +264,7 @@ static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
 	}
 
 	new->tx_cnt = desc_count;
-	new->async_tx.ack = orig_ack; /* client is in control of this ack */
+	new->async_tx.flags = orig_flags; /* client is in control of this ack */
 
 	/* store the original values for use in later cleanup */
 	if (new != first) {
@@ -304,14 +304,14 @@ static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
 	u32 copy;
 	size_t len;
 	dma_addr_t src, dst;
-	int orig_ack;
+	unsigned long orig_flags;
 	unsigned int desc_count = 0;
 
 	/* src and dest and len are stored in the initial descriptor */
 	len = first->len;
 	src = first->src;
 	dst = first->dst;
-	orig_ack = first->async_tx.ack;
+	orig_flags = first->async_tx.flags;
 	new = first;
 
 	/*
@@ -321,7 +321,7 @@ static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
 	do {
 		copy = min_t(size_t, len, ioat_chan->xfercap);
 
-		new->async_tx.ack = 1;
+		async_tx_ack(&new->async_tx);
 
 		hw = new->hw;
 		hw->size = copy;
@@ -349,7 +349,7 @@ static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
 	}
 
 	new->tx_cnt = desc_count;
-	new->async_tx.ack = orig_ack; /* client is in control of this ack */
+	new->async_tx.flags = orig_flags; /* client is in control of this ack */
 
 	/* store the original values for use in later cleanup */
 	if (new != first) {
@@ -714,7 +714,7 @@ static struct dma_async_tx_descriptor *ioat1_dma_prep_memcpy(
 		new->len = len;
 		new->dst = dma_dest;
 		new->src = dma_src;
-		new->async_tx.ack = 0;
+		new->async_tx.flags = flags;
 		return &new->async_tx;
 	} else
 		return NULL;
@@ -742,7 +742,7 @@ static struct dma_async_tx_descriptor *ioat2_dma_prep_memcpy(
 		new->len = len;
 		new->dst = dma_dest;
 		new->src = dma_src;
-		new->async_tx.ack = 0;
+		new->async_tx.flags = flags;
 		return &new->async_tx;
 	} else
 		return NULL;
@@ -842,7 +842,7 @@ static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
 				 * a completed entry, but not the last, so clean
 				 * up if the client is done with the descriptor
 				 */
-				if (desc->async_tx.ack) {
+				if (async_tx_test_ack(&desc->async_tx)) {
 					list_del(&desc->node);
 					list_add_tail(&desc->node,
 						      &ioat_chan->free_desc);
@@ -979,7 +979,7 @@ static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
 	desc->hw->size = 0;
 	desc->hw->src_addr = 0;
 	desc->hw->dst_addr = 0;
-	desc->async_tx.ack = 1;
+	async_tx_ack(&desc->async_tx);
 	switch (ioat_chan->device->version) {
 	case IOAT_VER_1_2:
 		desc->hw->next = 0;