Commit bbd603ef authored by Michael S. Tsirkin's avatar Michael S. Tsirkin Committed by Rusty Russell
Browse files

virtio: add_buf_gfp 



Add an add_buf variant that gets gfp parameter. Use that
to allocate indirect buffers.

Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
parent dc3f5e68

drivers/virtio/virtio_ring.c

+11 −9
Original line number Diff line number Diff line
@@ -110,13 +110,14 @@ struct vring_virtqueue 
static int vring_add_indirect(struct vring_virtqueue *vq,

			      struct scatterlist sg[],

			      unsigned int out,

			      unsigned int in)

			      unsigned int in,

			      gfp_t gfp)

{

	struct vring_desc *desc;

	unsigned head;

	int i;



	desc = kmalloc((out + in) * sizeof(struct vring_desc), GFP_ATOMIC);

	desc = kmalloc((out + in) * sizeof(struct vring_desc), gfp);

	if (!desc)

		return vq->vring.num;
@@ -155,11 +156,12 @@ static int vring_add_indirect(struct vring_virtqueue *vq, 
	return head;

}



int virtqueue_add_buf(struct virtqueue *_vq,

int virtqueue_add_buf_gfp(struct virtqueue *_vq,

			  struct scatterlist sg[],

			  unsigned int out,

			  unsigned int in,

		  void *data)

			  void *data,

			  gfp_t gfp)

{

	struct vring_virtqueue *vq = to_vvq(_vq);

	unsigned int i, avail, head, uninitialized_var(prev);
@@ -171,7 +173,7 @@ int virtqueue_add_buf(struct virtqueue *_vq, 
	/* If the host supports indirect descriptor tables, and we have multiple

	 * buffers, then go indirect. FIXME: tune this threshold */

	if (vq->indirect && (out + in) > 1 && vq->num_free) {

		head = vring_add_indirect(vq, sg, out, in);

		head = vring_add_indirect(vq, sg, out, in, gfp);

		if (head != vq->vring.num)

			goto add_head;

	}
@@ -232,7 +234,7 @@ int virtqueue_add_buf(struct virtqueue *_vq, 
		return vq->num_free ? vq->vring.num : 0;

	return vq->num_free;

}

EXPORT_SYMBOL_GPL(virtqueue_add_buf);

EXPORT_SYMBOL_GPL(virtqueue_add_buf_gfp);



void virtqueue_kick(struct virtqueue *_vq)

{

include/linux/virtio.h

+17 −5
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
#include <linux/spinlock.h>

#include <linux/device.h>

#include <linux/mod_devicetable.h>

#include <linux/gfp.h>



/**

 * virtqueue - a queue to register buffers for sending or receiving.
@@ -32,6 +33,7 @@ struct virtqueue { 
 *	out_num: the number of sg readable by other side

 *	in_num: the number of sg which are writable (after readable ones)

 *	data: the token identifying the buffer.

 *	gfp: how to do memory allocations (if necessary).

 *      Returns remaining capacity of queue (sg segments) or a negative error.

 * virtqueue_kick: update after add_buf

 *	vq: the struct virtqueue
@@ -60,11 +62,21 @@ struct virtqueue { 
 * All operations can be called in any context.

 */



int virtqueue_add_buf(struct virtqueue *vq,

int virtqueue_add_buf_gfp(struct virtqueue *vq,

			  struct scatterlist sg[],

			  unsigned int out_num,

			  unsigned int in_num,

		      void *data);

			  void *data,

			  gfp_t gfp);



static inline int virtqueue_add_buf(struct virtqueue *vq,

				    struct scatterlist sg[],

				    unsigned int out_num,

				    unsigned int in_num,

				    void *data)

{

	return virtqueue_add_buf_gfp(vq, sg, out_num, in_num, data, GFP_ATOMIC);

}



void virtqueue_kick(struct virtqueue *vq);