s390/virtio_ccw: use DMA handle from DMA API

Change and use ccw_device_dma_zalloc() so it returns a virtual address like
before, which can be used to access data. However also pass a new dma32_t
pointer type handle, which correlates to the returned virtual address.
This pointer is used to directly pass/set the DMA handle as returned by the
DMA API.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

3 files changed, 53 insertions, 46 deletions

diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 094431a62ad5..1d68db1a3d4e 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -1114,26 +1114,33 @@ static int cio_dma_pool_init(void)
 	return 0;
 }
 
-void *cio_gp_dma_zalloc(struct gen_pool *gp_dma, struct device *dma_dev,
-			size_t size)
+void *__cio_gp_dma_zalloc(struct gen_pool *gp_dma, struct device *dma_dev,
+			  size_t size, dma32_t *dma_handle)
 {
 	dma_addr_t dma_addr;
-	unsigned long addr;
 	size_t chunk_size;
+	void *addr;
 
 	if (!gp_dma)
 		return NULL;
-	addr = gen_pool_alloc(gp_dma, size);
+	addr = gen_pool_dma_alloc(gp_dma, size, &dma_addr);
 	while (!addr) {
 		chunk_size = round_up(size, PAGE_SIZE);
-		addr = (unsigned long) dma_alloc_coherent(dma_dev,
-					 chunk_size, &dma_addr, CIO_DMA_GFP);
+		addr = dma_alloc_coherent(dma_dev, chunk_size, &dma_addr, CIO_DMA_GFP);
 		if (!addr)
 			return NULL;
-		gen_pool_add_virt(gp_dma, addr, dma_addr, chunk_size, -1);
-		addr = gen_pool_alloc(gp_dma, size);
+		gen_pool_add_virt(gp_dma, (unsigned long)addr, dma_addr, chunk_size, -1);
+		addr = gen_pool_dma_alloc(gp_dma, size, dma_handle ? &dma_addr : NULL);
 	}
-	return (void *) addr;
+	if (dma_handle)
+		*dma_handle = (__force dma32_t)dma_addr;
+	return addr;
+}
+
+void *cio_gp_dma_zalloc(struct gen_pool *gp_dma, struct device *dma_dev,
+			size_t size)
+{
+	return __cio_gp_dma_zalloc(gp_dma, dma_dev, size, NULL);
 }
 
 void cio_gp_dma_free(struct gen_pool *gp_dma, void *cpu_addr, size_t size)
diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
index a5dba3829769..40c97f873075 100644
--- a/drivers/s390/cio/device_ops.c
+++ b/drivers/s390/cio/device_ops.c
@@ -823,13 +823,14 @@ EXPORT_SYMBOL_GPL(ccw_device_get_chid);
  * the subchannels dma pool. Maximal size of allocation supported
  * is PAGE_SIZE.
  */
-void *ccw_device_dma_zalloc(struct ccw_device *cdev, size_t size)
+void *ccw_device_dma_zalloc(struct ccw_device *cdev, size_t size,
+			    dma32_t *dma_handle)
 {
 	void *addr;
 
 	if (!get_device(&cdev->dev))
 		return NULL;
-	addr = cio_gp_dma_zalloc(cdev->private->dma_pool, &cdev->dev, size);
+	addr = __cio_gp_dma_zalloc(cdev->private->dma_pool, &cdev->dev, size, dma_handle);
 	if (IS_ERR_OR_NULL(addr))
 		put_device(&cdev->dev);
 	return addr;
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index ac77951c30c4..ee9c82721a7e 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -123,6 +123,7 @@ struct virtio_rev_info {
 
 struct virtio_ccw_vq_info {
 	struct virtqueue *vq;
+	dma32_t info_block_addr;
 	int num;
 	union {
 		struct vq_info_block s;
@@ -354,7 +355,8 @@ static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 
 	if (vcdev->is_thinint) {
 		thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
-						     sizeof(*thinint_area));
+						     sizeof(*thinint_area),
+						     &ccw->cda);
 		if (!thinint_area)
 			return;
 		thinint_area->summary_indicator =
@@ -362,17 +364,16 @@ static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 		thinint_area->isc = VIRTIO_AIRQ_ISC;
 		ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 		ccw->count = sizeof(*thinint_area);
-		ccw->cda = virt_to_dma32(thinint_area);
 	} else {
 		/* payload is the address of the indicators */
 		indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
-						   sizeof(indicators(vcdev)));
+						   sizeof(indicators(vcdev)),
+						   &ccw->cda);
 		if (!indicatorp)
 			return;
 		*indicatorp = 0;
 		ccw->cmd_code = CCW_CMD_SET_IND;
 		ccw->count = sizeof(indicators(vcdev));
-		ccw->cda = virt_to_dma32(indicatorp);
 	}
 	/* Deregister indicators from host. */
 	*indicators(vcdev) = 0;
@@ -463,7 +464,7 @@ static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 	}
 	ccw->cmd_code = CCW_CMD_SET_VQ;
 	ccw->flags = 0;
-	ccw->cda = virt_to_dma32(info->info_block);
+	ccw->cda = info->info_block_addr;
 	ret = ccw_io_helper(vcdev, ccw,
 			    VIRTIO_CCW_DOING_SET_VQ | index);
 	/*
@@ -486,7 +487,7 @@ static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 	struct ccw1 *ccw;
 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return;
 
@@ -525,7 +526,8 @@ static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 		goto out_err;
 	}
 	info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
-						 sizeof(*info->info_block));
+						 sizeof(*info->info_block),
+						 &info->info_block_addr);
 	if (!info->info_block) {
 		dev_warn(&vcdev->cdev->dev, "no info block\n");
 		err = -ENOMEM;
@@ -571,7 +573,7 @@ static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 	}
 	ccw->cmd_code = CCW_CMD_SET_VQ;
 	ccw->flags = 0;
-	ccw->cda = virt_to_dma32(info->info_block);
+	ccw->cda = info->info_block_addr;
 	err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 	if (err) {
 		dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
@@ -609,7 +611,8 @@ static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 	struct airq_info *info;
 
 	thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
-					     sizeof(*thinint_area));
+					     sizeof(*thinint_area),
+					     &ccw->cda);
 	if (!thinint_area) {
 		ret = -ENOMEM;
 		goto out;
@@ -630,7 +633,6 @@ static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 	ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 	ccw->flags = CCW_FLAG_SLI;
 	ccw->count = sizeof(*thinint_area);
-	ccw->cda = virt_to_dma32(thinint_area);
 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 	if (ret) {
 		if (ret == -EOPNOTSUPP) {
@@ -662,7 +664,7 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 	int ret, i, queue_idx = 0;
 	struct ccw1 *ccw;
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return -ENOMEM;
 
@@ -687,7 +689,8 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 	 * the address of the indicators.
 	*/
 	indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
-					   sizeof(indicators(vcdev)));
+					   sizeof(indicators(vcdev)),
+					   &ccw->cda);
 	if (!indicatorp)
 		goto out;
 	*indicatorp = virt_to_dma64(indicators(vcdev));
@@ -703,7 +706,6 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 		ccw->cmd_code = CCW_CMD_SET_IND;
 		ccw->flags = 0;
 		ccw->count = sizeof(indicators(vcdev));
-		ccw->cda = virt_to_dma32(indicatorp);
 		ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 		if (ret)
 			goto out;
@@ -714,7 +716,6 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 	ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 	ccw->flags = 0;
 	ccw->count = sizeof(indicators2(vcdev));
-	ccw->cda = virt_to_dma32(indicatorp);
 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 	if (ret)
 		goto out;
@@ -738,7 +739,7 @@ static void virtio_ccw_reset(struct virtio_device *vdev)
 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 	struct ccw1 *ccw;
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return;
 
@@ -762,11 +763,12 @@ static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 	u64 rc;
 	struct ccw1 *ccw;
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return 0;
 
-	features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
+	features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features),
+					 &ccw->cda);
 	if (!features) {
 		rc = 0;
 		goto out_free;
@@ -776,7 +778,6 @@ static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 	ccw->cmd_code = CCW_CMD_READ_FEAT;
 	ccw->flags = 0;
 	ccw->count = sizeof(*features);
-	ccw->cda = virt_to_dma32(features);
 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 	if (ret) {
 		rc = 0;
@@ -793,7 +794,6 @@ static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 	ccw->cmd_code = CCW_CMD_READ_FEAT;
 	ccw->flags = 0;
 	ccw->count = sizeof(*features);
-	ccw->cda = virt_to_dma32(features);
 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 	if (ret == 0)
 		rc |= (u64)le32_to_cpu(features->features) << 32;
@@ -825,11 +825,12 @@ static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 		return -EINVAL;
 	}
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return -ENOMEM;
 
-	features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
+	features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features),
+					 &ccw->cda);
 	if (!features) {
 		ret = -ENOMEM;
 		goto out_free;
@@ -846,7 +847,6 @@ static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 	ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 	ccw->flags = 0;
 	ccw->count = sizeof(*features);
-	ccw->cda = virt_to_dma32(features);
 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 	if (ret)
 		goto out_free;
@@ -860,7 +860,6 @@ static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 	ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 	ccw->flags = 0;
 	ccw->count = sizeof(*features);
-	ccw->cda = virt_to_dma32(features);
 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 
 out_free:
@@ -879,12 +878,13 @@ static void virtio_ccw_get_config(struct virtio_device *vdev,
 	void *config_area;
 	unsigned long flags;
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return;
 
 	config_area = ccw_device_dma_zalloc(vcdev->cdev,
-					    VIRTIO_CCW_CONFIG_SIZE);
+					    VIRTIO_CCW_CONFIG_SIZE,
+					    &ccw->cda);
 	if (!config_area)
 		goto out_free;
 
@@ -892,7 +892,6 @@ static void virtio_ccw_get_config(struct virtio_device *vdev,
 	ccw->cmd_code = CCW_CMD_READ_CONF;
 	ccw->flags = 0;
 	ccw->count = offset + len;
-	ccw->cda = virt_to_dma32(config_area);
 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 	if (ret)
 		goto out_free;
@@ -919,12 +918,13 @@ static void virtio_ccw_set_config(struct virtio_device *vdev,
 	void *config_area;
 	unsigned long flags;
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return;
 
 	config_area = ccw_device_dma_zalloc(vcdev->cdev,
-					    VIRTIO_CCW_CONFIG_SIZE);
+					    VIRTIO_CCW_CONFIG_SIZE,
+					    &ccw->cda);
 	if (!config_area)
 		goto out_free;
 
@@ -939,7 +939,6 @@ static void virtio_ccw_set_config(struct virtio_device *vdev,
 	ccw->cmd_code = CCW_CMD_WRITE_CONF;
 	ccw->flags = 0;
 	ccw->count = offset + len;
-	ccw->cda = virt_to_dma32(config_area);
 	ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 
 out_free:
@@ -956,7 +955,7 @@ static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 	if (vcdev->revision < 2)
 		return vcdev->dma_area->status;
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return old_status;
 
@@ -983,7 +982,7 @@ static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 	struct ccw1 *ccw;
 	int ret;
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return;
 
@@ -1278,10 +1277,10 @@ static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
 	struct ccw1 *ccw;
 	int ret;
 
-	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
+	ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 	if (!ccw)
 		return -ENOMEM;
-	rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
+	rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev), &ccw->cda);
 	if (!rev) {
 		ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 		return -ENOMEM;
@@ -1291,7 +1290,6 @@ static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
 	ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
 	ccw->flags = 0;
 	ccw->count = sizeof(*rev);
-	ccw->cda = virt_to_dma32(rev);
 
 	vcdev->revision = VIRTIO_CCW_REV_MAX;
 	do {
@@ -1333,7 +1331,8 @@ static int virtio_ccw_online(struct ccw_device *cdev)
 	vcdev->vdev.dev.parent = &cdev->dev;
 	vcdev->cdev = cdev;
 	vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
-						sizeof(*vcdev->dma_area));
+						sizeof(*vcdev->dma_area),
+						NULL);
 	if (!vcdev->dma_area) {
 		ret = -ENOMEM;
 		goto out_free;