struct vring_desc_state desc_state[];
};
+
+/*
+ * Helpers.
+ */
+
#define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq)
/*
cpu_addr, size, direction);
}
+static int vring_mapping_error(const struct vring_virtqueue *vq,
+ dma_addr_t addr)
+{
+ if (!vring_use_dma_api(vq->vq.vdev))
+ return 0;
+
+ return dma_mapping_error(vring_dma_dev(vq), addr);
+}
+
+
+/*
+ * Split ring specific functions - *_split().
+ */
+
static void vring_unmap_one_split(const struct vring_virtqueue *vq,
struct vring_desc *desc)
{
}
}
-static int vring_mapping_error(const struct vring_virtqueue *vq,
- dma_addr_t addr)
-{
- if (!vring_use_dma_api(vq->vq.vdev))
- return 0;
-
- return dma_mapping_error(vring_dma_dev(vq), addr);
-}
-
static struct vring_desc *alloc_indirect_split(struct virtqueue *_vq,
unsigned int total_sg,
gfp_t gfp)
return -EIO;
}
-static inline int virtqueue_add(struct virtqueue *_vq,
- struct scatterlist *sgs[],
- unsigned int total_sg,
- unsigned int out_sgs,
- unsigned int in_sgs,
- void *data,
- void *ctx,
- gfp_t gfp)
-{
- return virtqueue_add_split(_vq, sgs, total_sg,
- out_sgs, in_sgs, data, ctx, gfp);
-}
-
-/**
- * virtqueue_add_sgs - expose buffers to other end
- * @vq: the struct virtqueue we're talking about.
- * @sgs: array of terminated scatterlists.
- * @out_num: the number of scatterlists readable by other side
- * @in_num: the number of scatterlists which are writable (after readable ones)
- * @data: the token identifying the buffer.
- * @gfp: how to do memory allocations (if necessary).
- *
- * Caller must ensure we don't call this with other virtqueue operations
- * at the same time (except where noted).
- *
- * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
- */
-int virtqueue_add_sgs(struct virtqueue *_vq,
- struct scatterlist *sgs[],
- unsigned int out_sgs,
- unsigned int in_sgs,
- void *data,
- gfp_t gfp)
-{
- unsigned int i, total_sg = 0;
-
- /* Count them first. */
- for (i = 0; i < out_sgs + in_sgs; i++) {
- struct scatterlist *sg;
- for (sg = sgs[i]; sg; sg = sg_next(sg))
- total_sg++;
- }
- return virtqueue_add(_vq, sgs, total_sg, out_sgs, in_sgs,
- data, NULL, gfp);
-}
-EXPORT_SYMBOL_GPL(virtqueue_add_sgs);
-
-/**
- * virtqueue_add_outbuf - expose output buffers to other end
- * @vq: the struct virtqueue we're talking about.
- * @sg: scatterlist (must be well-formed and terminated!)
- * @num: the number of entries in @sg readable by other side
- * @data: the token identifying the buffer.
- * @gfp: how to do memory allocations (if necessary).
- *
- * Caller must ensure we don't call this with other virtqueue operations
- * at the same time (except where noted).
- *
- * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
- */
-int virtqueue_add_outbuf(struct virtqueue *vq,
- struct scatterlist *sg, unsigned int num,
- void *data,
- gfp_t gfp)
-{
- return virtqueue_add(vq, &sg, num, 1, 0, data, NULL, gfp);
-}
-EXPORT_SYMBOL_GPL(virtqueue_add_outbuf);
-
-/**
- * virtqueue_add_inbuf - expose input buffers to other end
- * @vq: the struct virtqueue we're talking about.
- * @sg: scatterlist (must be well-formed and terminated!)
- * @num: the number of entries in @sg writable by other side
- * @data: the token identifying the buffer.
- * @gfp: how to do memory allocations (if necessary).
- *
- * Caller must ensure we don't call this with other virtqueue operations
- * at the same time (except where noted).
- *
- * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
- */
-int virtqueue_add_inbuf(struct virtqueue *vq,
- struct scatterlist *sg, unsigned int num,
- void *data,
- gfp_t gfp)
-{
- return virtqueue_add(vq, &sg, num, 0, 1, data, NULL, gfp);
-}
-EXPORT_SYMBOL_GPL(virtqueue_add_inbuf);
-
-/**
- * virtqueue_add_inbuf_ctx - expose input buffers to other end
- * @vq: the struct virtqueue we're talking about.
- * @sg: scatterlist (must be well-formed and terminated!)
- * @num: the number of entries in @sg writable by other side
- * @data: the token identifying the buffer.
- * @ctx: extra context for the token
- * @gfp: how to do memory allocations (if necessary).
- *
- * Caller must ensure we don't call this with other virtqueue operations
- * at the same time (except where noted).
- *
- * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
- */
-int virtqueue_add_inbuf_ctx(struct virtqueue *vq,
- struct scatterlist *sg, unsigned int num,
- void *data,
- void *ctx,
- gfp_t gfp)
-{
- return virtqueue_add(vq, &sg, num, 0, 1, data, ctx, gfp);
-}
-EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_ctx);
-
static bool virtqueue_kick_prepare_split(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
return needs_kick;
}
-/**
- * virtqueue_kick_prepare - first half of split virtqueue_kick call.
- * @vq: the struct virtqueue
- *
- * Instead of virtqueue_kick(), you can do:
- * if (virtqueue_kick_prepare(vq))
- * virtqueue_notify(vq);
- *
- * This is sometimes useful because the virtqueue_kick_prepare() needs
- * to be serialized, but the actual virtqueue_notify() call does not.
- */
-bool virtqueue_kick_prepare(struct virtqueue *_vq)
-{
- return virtqueue_kick_prepare_split(_vq);
-}
-EXPORT_SYMBOL_GPL(virtqueue_kick_prepare);
-
-/**
- * virtqueue_notify - second half of split virtqueue_kick call.
- * @vq: the struct virtqueue
- *
- * This does not need to be serialized.
- *
- * Returns false if host notify failed or queue is broken, otherwise true.
- */
-bool virtqueue_notify(struct virtqueue *_vq)
-{
- struct vring_virtqueue *vq = to_vvq(_vq);
-
- if (unlikely(vq->broken))
- return false;
-
- /* Prod other side to tell it about changes. */
- if (!vq->notify(_vq)) {
- vq->broken = true;
- return false;
- }
- return true;
-}
-EXPORT_SYMBOL_GPL(virtqueue_notify);
-
-/**
- * virtqueue_kick - update after add_buf
- * @vq: the struct virtqueue
- *
- * After one or more virtqueue_add_* calls, invoke this to kick
- * the other side.
- *
- * Caller must ensure we don't call this with other virtqueue
- * operations at the same time (except where noted).
- *
- * Returns false if kick failed, otherwise true.
- */
-bool virtqueue_kick(struct virtqueue *vq)
-{
- if (virtqueue_kick_prepare(vq))
- return virtqueue_notify(vq);
- return true;
-}
-EXPORT_SYMBOL_GPL(virtqueue_kick);
-
static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head,
void **ctx)
{
return ret;
}
-/**
- * virtqueue_get_buf - get the next used buffer
- * @vq: the struct virtqueue we're talking about.
- * @len: the length written into the buffer
- *
- * If the device wrote data into the buffer, @len will be set to the
- * amount written. This means you don't need to clear the buffer
- * beforehand to ensure there's no data leakage in the case of short
- * writes.
- *
- * Caller must ensure we don't call this with other virtqueue
- * operations at the same time (except where noted).
- *
- * Returns NULL if there are no used buffers, or the "data" token
- * handed to virtqueue_add_*().
- */
-void *virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int *len,
- void **ctx)
-{
- return virtqueue_get_buf_ctx_split(_vq, len, ctx);
-}
-EXPORT_SYMBOL_GPL(virtqueue_get_buf_ctx);
-
-void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len)
-{
- return virtqueue_get_buf_ctx(_vq, len, NULL);
-}
-EXPORT_SYMBOL_GPL(virtqueue_get_buf);
-
static void virtqueue_disable_cb_split(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
}
}
-/**
- * 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.
- *
- * Unlike other operations, this need not be serialized.
- */
-void virtqueue_disable_cb(struct virtqueue *_vq)
-{
- virtqueue_disable_cb_split(_vq);
-}
-EXPORT_SYMBOL_GPL(virtqueue_disable_cb);
-
static unsigned virtqueue_enable_cb_prepare_split(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
return last_used_idx;
}
-/**
- * virtqueue_enable_cb_prepare - restart callbacks after disable_cb
- * @vq: the struct virtqueue we're talking about.
- *
- * This re-enables callbacks; it returns current queue state
- * in an opaque unsigned value. This value should be later tested by
- * virtqueue_poll, to detect a possible race between the driver checking for
- * more work, and enabling callbacks.
- *
- * Caller must ensure we don't call this with other virtqueue
- * operations at the same time (except where noted).
- */
-unsigned virtqueue_enable_cb_prepare(struct virtqueue *_vq)
-{
- return virtqueue_enable_cb_prepare_split(_vq);
-}
-EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare);
-
static bool virtqueue_poll_split(struct virtqueue *_vq, unsigned last_used_idx)
{
struct vring_virtqueue *vq = to_vvq(_vq);
vq->vring.used->idx);
}
-/**
- * virtqueue_poll - query pending used buffers
- * @vq: the struct virtqueue we're talking about.
- * @last_used_idx: virtqueue state (from call to virtqueue_enable_cb_prepare).
- *
- * Returns "true" if there are pending used buffers in the queue.
- *
- * This does not need to be serialized.
- */
-bool virtqueue_poll(struct virtqueue *_vq, unsigned last_used_idx)
-{
- struct vring_virtqueue *vq = to_vvq(_vq);
-
- virtio_mb(vq->weak_barriers);
- return virtqueue_poll_split(_vq, last_used_idx);
-}
-EXPORT_SYMBOL_GPL(virtqueue_poll);
-
-/**
- * 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.
- *
- * Caller must ensure we don't call this with other virtqueue
- * operations at the same time (except where noted).
- */
-bool virtqueue_enable_cb(struct virtqueue *_vq)
-{
- unsigned last_used_idx = virtqueue_enable_cb_prepare(_vq);
- return !virtqueue_poll(_vq, last_used_idx);
-}
-EXPORT_SYMBOL_GPL(virtqueue_enable_cb);
-
static bool virtqueue_enable_cb_delayed_split(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
return true;
}
-/**
- * virtqueue_enable_cb_delayed - restart callbacks after disable_cb.
- * @vq: the struct virtqueue we're talking about.
- *
- * This re-enables callbacks but hints to the other side to delay
- * interrupts until most of the available buffers have been processed;
- * it returns "false" if there are many pending buffers in the queue,
- * to detect a possible race between the driver checking for more work,
- * and enabling callbacks.
- *
- * Caller must ensure we don't call this with other virtqueue
- * operations at the same time (except where noted).
- */
-bool virtqueue_enable_cb_delayed(struct virtqueue *_vq)
-{
- return virtqueue_enable_cb_delayed_split(_vq);
-}
-EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed);
-
static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
return NULL;
}
+
+/*
+ * Generic functions and exported symbols.
+ */
+
+static inline int virtqueue_add(struct virtqueue *_vq,
+ struct scatterlist *sgs[],
+ unsigned int total_sg,
+ unsigned int out_sgs,
+ unsigned int in_sgs,
+ void *data,
+ void *ctx,
+ gfp_t gfp)
+{
+ return virtqueue_add_split(_vq, sgs, total_sg,
+ out_sgs, in_sgs, data, ctx, gfp);
+}
+
+/**
+ * virtqueue_add_sgs - expose buffers to other end
+ * @vq: the struct virtqueue we're talking about.
+ * @sgs: array of terminated scatterlists.
+ * @out_num: the number of scatterlists readable by other side
+ * @in_num: the number of scatterlists which are writable (after readable ones)
+ * @data: the token identifying the buffer.
+ * @gfp: how to do memory allocations (if necessary).
+ *
+ * Caller must ensure we don't call this with other virtqueue operations
+ * at the same time (except where noted).
+ *
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
+ */
+int virtqueue_add_sgs(struct virtqueue *_vq,
+ struct scatterlist *sgs[],
+ unsigned int out_sgs,
+ unsigned int in_sgs,
+ void *data,
+ gfp_t gfp)
+{
+ unsigned int i, total_sg = 0;
+
+ /* Count them first. */
+ for (i = 0; i < out_sgs + in_sgs; i++) {
+ struct scatterlist *sg;
+
+ for (sg = sgs[i]; sg; sg = sg_next(sg))
+ total_sg++;
+ }
+ return virtqueue_add(_vq, sgs, total_sg, out_sgs, in_sgs,
+ data, NULL, gfp);
+}
+EXPORT_SYMBOL_GPL(virtqueue_add_sgs);
+
+/**
+ * virtqueue_add_outbuf - expose output buffers to other end
+ * @vq: the struct virtqueue we're talking about.
+ * @sg: scatterlist (must be well-formed and terminated!)
+ * @num: the number of entries in @sg readable by other side
+ * @data: the token identifying the buffer.
+ * @gfp: how to do memory allocations (if necessary).
+ *
+ * Caller must ensure we don't call this with other virtqueue operations
+ * at the same time (except where noted).
+ *
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
+ */
+int virtqueue_add_outbuf(struct virtqueue *vq,
+ struct scatterlist *sg, unsigned int num,
+ void *data,
+ gfp_t gfp)
+{
+ return virtqueue_add(vq, &sg, num, 1, 0, data, NULL, gfp);
+}
+EXPORT_SYMBOL_GPL(virtqueue_add_outbuf);
+
+/**
+ * virtqueue_add_inbuf - expose input buffers to other end
+ * @vq: the struct virtqueue we're talking about.
+ * @sg: scatterlist (must be well-formed and terminated!)
+ * @num: the number of entries in @sg writable by other side
+ * @data: the token identifying the buffer.
+ * @gfp: how to do memory allocations (if necessary).
+ *
+ * Caller must ensure we don't call this with other virtqueue operations
+ * at the same time (except where noted).
+ *
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
+ */
+int virtqueue_add_inbuf(struct virtqueue *vq,
+ struct scatterlist *sg, unsigned int num,
+ void *data,
+ gfp_t gfp)
+{
+ return virtqueue_add(vq, &sg, num, 0, 1, data, NULL, gfp);
+}
+EXPORT_SYMBOL_GPL(virtqueue_add_inbuf);
+
+/**
+ * virtqueue_add_inbuf_ctx - expose input buffers to other end
+ * @vq: the struct virtqueue we're talking about.
+ * @sg: scatterlist (must be well-formed and terminated!)
+ * @num: the number of entries in @sg writable by other side
+ * @data: the token identifying the buffer.
+ * @ctx: extra context for the token
+ * @gfp: how to do memory allocations (if necessary).
+ *
+ * Caller must ensure we don't call this with other virtqueue operations
+ * at the same time (except where noted).
+ *
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
+ */
+int virtqueue_add_inbuf_ctx(struct virtqueue *vq,
+ struct scatterlist *sg, unsigned int num,
+ void *data,
+ void *ctx,
+ gfp_t gfp)
+{
+ return virtqueue_add(vq, &sg, num, 0, 1, data, ctx, gfp);
+}
+EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_ctx);
+
+/**
+ * virtqueue_kick_prepare - first half of split virtqueue_kick call.
+ * @vq: the struct virtqueue
+ *
+ * Instead of virtqueue_kick(), you can do:
+ * if (virtqueue_kick_prepare(vq))
+ * virtqueue_notify(vq);
+ *
+ * This is sometimes useful because the virtqueue_kick_prepare() needs
+ * to be serialized, but the actual virtqueue_notify() call does not.
+ */
+bool virtqueue_kick_prepare(struct virtqueue *_vq)
+{
+ return virtqueue_kick_prepare_split(_vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_kick_prepare);
+
+/**
+ * virtqueue_notify - second half of split virtqueue_kick call.
+ * @vq: the struct virtqueue
+ *
+ * This does not need to be serialized.
+ *
+ * Returns false if host notify failed or queue is broken, otherwise true.
+ */
+bool virtqueue_notify(struct virtqueue *_vq)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ if (unlikely(vq->broken))
+ return false;
+
+ /* Prod other side to tell it about changes. */
+ if (!vq->notify(_vq)) {
+ vq->broken = true;
+ return false;
+ }
+ return true;
+}
+EXPORT_SYMBOL_GPL(virtqueue_notify);
+
+/**
+ * virtqueue_kick - update after add_buf
+ * @vq: the struct virtqueue
+ *
+ * After one or more virtqueue_add_* calls, invoke this to kick
+ * the other side.
+ *
+ * Caller must ensure we don't call this with other virtqueue
+ * operations at the same time (except where noted).
+ *
+ * Returns false if kick failed, otherwise true.
+ */
+bool virtqueue_kick(struct virtqueue *vq)
+{
+ if (virtqueue_kick_prepare(vq))
+ return virtqueue_notify(vq);
+ return true;
+}
+EXPORT_SYMBOL_GPL(virtqueue_kick);
+
+/**
+ * virtqueue_get_buf - get the next used buffer
+ * @vq: the struct virtqueue we're talking about.
+ * @len: the length written into the buffer
+ *
+ * If the device wrote data into the buffer, @len will be set to the
+ * amount written. This means you don't need to clear the buffer
+ * beforehand to ensure there's no data leakage in the case of short
+ * writes.
+ *
+ * Caller must ensure we don't call this with other virtqueue
+ * operations at the same time (except where noted).
+ *
+ * Returns NULL if there are no used buffers, or the "data" token
+ * handed to virtqueue_add_*().
+ */
+void *virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int *len,
+ void **ctx)
+{
+ return virtqueue_get_buf_ctx_split(_vq, len, ctx);
+}
+EXPORT_SYMBOL_GPL(virtqueue_get_buf_ctx);
+
+void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len)
+{
+ return virtqueue_get_buf_ctx(_vq, len, NULL);
+}
+EXPORT_SYMBOL_GPL(virtqueue_get_buf);
+
+/**
+ * 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.
+ *
+ * Unlike other operations, this need not be serialized.
+ */
+void virtqueue_disable_cb(struct virtqueue *_vq)
+{
+ virtqueue_disable_cb_split(_vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_disable_cb);
+
+/**
+ * virtqueue_enable_cb_prepare - restart callbacks after disable_cb
+ * @vq: the struct virtqueue we're talking about.
+ *
+ * This re-enables callbacks; it returns current queue state
+ * in an opaque unsigned value. This value should be later tested by
+ * virtqueue_poll, to detect a possible race between the driver checking for
+ * more work, and enabling callbacks.
+ *
+ * Caller must ensure we don't call this with other virtqueue
+ * operations at the same time (except where noted).
+ */
+unsigned virtqueue_enable_cb_prepare(struct virtqueue *_vq)
+{
+ return virtqueue_enable_cb_prepare_split(_vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare);
+
+/**
+ * virtqueue_poll - query pending used buffers
+ * @vq: the struct virtqueue we're talking about.
+ * @last_used_idx: virtqueue state (from call to virtqueue_enable_cb_prepare).
+ *
+ * Returns "true" if there are pending used buffers in the queue.
+ *
+ * This does not need to be serialized.
+ */
+bool virtqueue_poll(struct virtqueue *_vq, unsigned last_used_idx)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ virtio_mb(vq->weak_barriers);
+ return virtqueue_poll_split(_vq, last_used_idx);
+}
+EXPORT_SYMBOL_GPL(virtqueue_poll);
+
+/**
+ * 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.
+ *
+ * Caller must ensure we don't call this with other virtqueue
+ * operations at the same time (except where noted).
+ */
+bool virtqueue_enable_cb(struct virtqueue *_vq)
+{
+ unsigned last_used_idx = virtqueue_enable_cb_prepare(_vq);
+
+ return !virtqueue_poll(_vq, last_used_idx);
+}
+EXPORT_SYMBOL_GPL(virtqueue_enable_cb);
+
+/**
+ * virtqueue_enable_cb_delayed - restart callbacks after disable_cb.
+ * @vq: the struct virtqueue we're talking about.
+ *
+ * This re-enables callbacks but hints to the other side to delay
+ * interrupts until most of the available buffers have been processed;
+ * it returns "false" if there are many pending buffers in the queue,
+ * to detect a possible race between the driver checking for more work,
+ * and enabling callbacks.
+ *
+ * Caller must ensure we don't call this with other virtqueue
+ * operations at the same time (except where noted).
+ */
+bool virtqueue_enable_cb_delayed(struct virtqueue *_vq)
+{
+ return virtqueue_enable_cb_delayed_split(_vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed);
+
/**
* virtqueue_detach_unused_buf - detach first unused buffer
* @vq: the struct virtqueue we're talking about.
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