diff options
Diffstat (limited to 'include/linux/virtio.h')
-rw-r--r-- | include/linux/virtio.h | 55 |
1 files changed, 33 insertions, 22 deletions
diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 40d1709bdbf..aff5b4f7404 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -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. @@ -14,7 +15,6 @@ * @callback: the function to call when buffers are consumed (can be NULL). * @name: the name of this virtqueue (mainly for debugging) * @vdev: the virtio device this queue was created for. - * @vq_ops: the operations for this virtqueue (see below). * @priv: a pointer for the virtqueue implementation to use. */ struct virtqueue { @@ -22,60 +22,71 @@ struct virtqueue { void (*callback)(struct virtqueue *vq); const char *name; struct virtio_device *vdev; - struct virtqueue_ops *vq_ops; void *priv; }; /** - * virtqueue_ops - operations for virtqueue abstraction layer - * @add_buf: expose buffer to other end + * operations for virtqueue + * virtqueue_add_buf: expose buffer to other end * vq: the struct virtqueue we're talking about. * sg: the description of the buffer(s). * 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. - * @kick: update after add_buf + * virtqueue_kick: update after add_buf * vq: the struct virtqueue * After one or more add_buf calls, invoke this to kick the other side. - * @get_buf: get the next used buffer + * virtqueue_get_buf: get the next used buffer * vq: the struct virtqueue we're talking about. * len: the length written into the buffer * Returns NULL or the "data" token handed to add_buf. - * @disable_cb: disable callbacks + * virtqueue_disable_cb: disable callbacks * vq: the struct virtqueue we're talking about. * Note that this is not necessarily synchronous, hence unreliable and only * useful as an optimization. - * @enable_cb: restart callbacks after disable_cb. + * virtqueue_enable_cb: restart callbacks after disable_cb. * vq: the struct virtqueue we're talking about. * This re-enables callbacks; it returns "false" if there are pending * buffers in the queue, to detect a possible race between the driver * checking for more work, and enabling callbacks. - * @detach_unused_buf: detach first unused buffer + * virtqueue_detach_unused_buf: detach first unused buffer * vq: the struct virtqueue we're talking about. * Returns NULL or the "data" token handed to add_buf * * Locking rules are straightforward: the driver is responsible for * locking. No two operations may be invoked simultaneously, with the exception - * of @disable_cb. + * of virtqueue_disable_cb. * * All operations can be called in any context. */ -struct virtqueue_ops { - int (*add_buf)(struct virtqueue *vq, - struct scatterlist sg[], - unsigned int out_num, - unsigned int in_num, - void *data); - void (*kick)(struct virtqueue *vq); +int virtqueue_add_buf_gfp(struct virtqueue *vq, + struct scatterlist sg[], + unsigned int out_num, + unsigned int in_num, + void *data, + gfp_t gfp); - void *(*get_buf)(struct virtqueue *vq, unsigned int *len); +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 (*disable_cb)(struct virtqueue *vq); - bool (*enable_cb)(struct virtqueue *vq); - void *(*detach_unused_buf)(struct virtqueue *vq); -}; +void virtqueue_kick(struct virtqueue *vq); + +void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len); + +void virtqueue_disable_cb(struct virtqueue *vq); + +bool virtqueue_enable_cb(struct virtqueue *vq); + +void *virtqueue_detach_unused_buf(struct virtqueue *vq); /** * virtio_device - representation of a device using virtio |