There is already a virtqueue abstract structure in virtio subsystem
(see struct virtqueue in include/linux/virtio.h), however the vring
based virtqueue is used only in the past years, the virtqueue related
methods mix much with vring(just look like the codes, virtqueue_xxx
functions are implemented in virtio_ring.c).
Abstract virtqueue related methods(see struct virtqueue_ops), and
separate virtqueue_xxx symbols from vring. This allows a non-vring
based transport in the future. With this change, the following symbols
are exported from virtio.ko instead of virtio_ring.ko:
virtqueue_add_sgs
virtqueue_add_outbuf
virtqueue_add_inbuf
virtqueue_add_inbuf_ctx
virtqueue_kick_prepare
virtqueue_notify
virtqueue_kick
virtqueue_enable_cb_prepare
virtqueue_enable_cb
virtqueue_enable_cb_delayed
virtqueue_disable_cb
virtqueue_poll
virtqueue_get_buf_ctx
virtqueue_get_buf
virtqueue_detach_unused_buf
virtqueue_get_vring_size
virtqueue_resize
virtqueue_is_broken
virtio_break_device
__virtio_unbreak_device
Cc: Stefan Hajnoczi <stefanha at redhat.com>
Signed-off-by: zhenwei pi <pizhenwei at bytedance.com>
---
drivers/virtio/virtio.c | 362 +++++++++++++++++++++++++++++++++++
drivers/virtio/virtio_ring.c | 282 +++++----------------------
include/linux/virtio.h | 29 +++
3 files changed, 443 insertions(+), 230 deletions(-)
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 3893dc29eb26..8d8715a10f26 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -553,6 +553,368 @@ int virtio_device_restore(struct virtio_device *dev)
EXPORT_SYMBOL_GPL(virtio_device_restore);
#endif
+/**
+ * virtqueue_add_sgs - expose buffers to other end
+ * @vq: the struct virtqueue we're talking about.
+ * @sgs: array of terminated scatterlists.
+ * @out_sgs: the number of scatterlists readable by other side
+ * @in_sgs: 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 vq->ops->add_sgs(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 vq->ops->add_sgs(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 vq->ops->add_sgs(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 vq->ops->add_sgs(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 vq->ops->kick_prepare(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)
+{
+ return vq->ops->notify(vq);
+}
+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_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 int virtqueue_enable_cb_prepare(struct virtqueue *vq)
+{
+ return vq->ops->enable_cb_prepare(vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare);
+
+/**
+ * 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 int val = vq->ops->enable_cb_prepare(vq);
+
+ return !vq->ops->poll(vq, val);
+}
+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 vq->ops->enable_cb_delayed(vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed);
+
+/**
+ * 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)
+{
+ vq->ops->disable_cb(vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_disable_cb);
+
+/**
+ * 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 int idx)
+{
+ return vq->ops->poll(vq, idx);
+}
+EXPORT_SYMBOL_GPL(virtqueue_poll);
+
+/**
+ * virtqueue_get_buf_ctx - get the next used buffer
+ * @vq: the struct virtqueue we're talking about.
+ * @len: the length written into the buffer
+ * @ctx: extra context for the token
+ *
+ * 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 vq->ops->get_buf_ctx(vq, len, ctx);
+}
+EXPORT_SYMBOL_GPL(virtqueue_get_buf_ctx);
+
+void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len)
+{
+ return vq->ops->get_buf_ctx(vq, len, NULL);
+}
+EXPORT_SYMBOL_GPL(virtqueue_get_buf);
+
+/**
+ * virtqueue_detach_unused_buf - detach first unused buffer
+ * @vq: the struct virtqueue we're talking about.
+ *
+ * Returns NULL or the "data" token handed to virtqueue_add_*().
+ * This is not valid on an active queue; it is useful for device
+ * shutdown or the reset queue.
+ */
+void *virtqueue_detach_unused_buf(struct virtqueue *vq)
+{
+ return vq->ops->detach_unused_buf(vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf);
+
+/**
+ * virtqueue_get_vring_size - return the size of the virtqueue's vring
+ * @vq: the struct virtqueue containing the vring of interest.
+ *
+ * Returns the size of the vring. This is mainly used for boasting to
+ * userspace. Unlike other operations, this need not be serialized.
+ */
+unsigned int virtqueue_get_vring_size(const struct virtqueue *vq)
+{
+ return vq->ops->get_vring_size(vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_get_vring_size);
+
+/**
+ * virtqueue_resize - resize the vring of vq
+ * @vq: the struct virtqueue we're talking about.
+ * @num: new ring num
+ * @recycle: callback for recycle the useless buffer
+ *
+ * When it is really necessary to create a new vring, it will set the current
vq
+ * into the reset state. Then call the passed callback to recycle the buffer
+ * that is no longer used. Only after the new vring is successfully created,
the
+ * old vring will be released.
+ *
+ * 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.
+ * 0: success.
+ * -ENOMEM: Failed to allocate a new ring, fall back to the original ring size.
+ * vq can still work normally
+ * -EBUSY: Failed to sync with device, vq may not work properly
+ * -ENOENT: Transport or device not supported
+ * -E2BIG/-EINVAL: num error
+ * -EPERM: Operation not permitted
+ *
+ */
+int virtqueue_resize(struct virtqueue *vq, u32 num,
+ void (*recycle)(struct virtqueue *vq, void *buf))
+{
+ if (vq->ops->resize)
+ return vq->ops->resize(vq, num, recycle);
+
+ return -ENOENT;
+}
+EXPORT_SYMBOL_GPL(virtqueue_resize);
+
+bool virtqueue_is_broken(const struct virtqueue *vq)
+{
+ return vq->ops->is_broken(vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_is_broken);
+
+/*
+ * This should prevent the device from being used, allowing drivers to
+ * recover. You may need to grab appropriate locks to flush.
+ */
+void virtio_break_device(struct virtio_device *dev)
+{
+ struct virtqueue *vq;
+
+ spin_lock(&dev->vqs_list_lock);
+ list_for_each_entry(vq, &dev->vqs, list) {
+ vq->ops->__break(vq);
+ }
+ spin_unlock(&dev->vqs_list_lock);
+}
+EXPORT_SYMBOL_GPL(virtio_break_device);
+
+/*
+ * This should allow the device to be used by the driver. You may
+ * need to grab appropriate locks to flush the write to
+ * vq->broken. This should only be used in some specific case e.g
+ * (probing and restoring). This function should only be called by the
+ * core, not directly by the driver.
+ */
+void __virtio_unbreak_device(struct virtio_device *dev)
+{
+ struct virtqueue *vq;
+
+ spin_lock(&dev->vqs_list_lock);
+ list_for_each_entry(vq, &dev->vqs, list) {
+ vq->ops->__unbreak(vq);
+ }
+ spin_unlock(&dev->vqs_list_lock);
+}
+EXPORT_SYMBOL_GPL(__virtio_unbreak_device);
+
static int virtio_init(void)
{
if (bus_register(&virtio_bus) != 0)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index c5310eaf8b46..7b86417255db 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -227,6 +227,8 @@ static struct virtqueue *__vring_new_virtqueue(unsigned int
index,
static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num);
static void vring_free(struct virtqueue *_vq);
+static struct virtqueue_ops vring_ops;
+
/*
* Helpers.
*/
@@ -2041,6 +2043,7 @@ static struct virtqueue *vring_create_virtqueue_packed(
vq->vq.name = name;
vq->vq.index = index;
vq->vq.reset = false;
+ vq->vq.ops = &vring_ops;
vq->we_own_ring = true;
vq->notify = notify;
vq->weak_barriers = weak_barriers;
@@ -2114,17 +2117,17 @@ static int virtqueue_resize_packed(struct virtqueue
*_vq, u32 num)
/*
- * Generic functions and exported symbols.
+ * Vring specific operation functions
*/
-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)
+static inline int vring_virtqueue_add_sgs(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)
{
struct vring_virtqueue *vq = to_vvq(_vq);
@@ -2135,110 +2138,7 @@ static inline int virtqueue_add(struct virtqueue *_vq,
}
/**
- * virtqueue_add_sgs - expose buffers to other end
- * @_vq: the struct virtqueue we're talking about.
- * @sgs: array of terminated scatterlists.
- * @out_sgs: the number of scatterlists readable by other side
- * @in_sgs: 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.
+ * vring_virtqueue_kick_prepare - first half of split virtqueue_kick call.
* @_vq: the struct virtqueue
*
* Instead of virtqueue_kick(), you can do:
@@ -2248,24 +2148,23 @@ EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_ctx);
* 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)
+static bool vring_virtqueue_kick_prepare(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
return vq->packed_ring ? virtqueue_kick_prepare_packed(_vq) :
virtqueue_kick_prepare_split(_vq);
}
-EXPORT_SYMBOL_GPL(virtqueue_kick_prepare);
/**
- * virtqueue_notify - second half of split virtqueue_kick call.
+ * vring_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)
+static bool vring_virtqueue_notify(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
@@ -2279,30 +2178,9 @@ bool virtqueue_notify(struct virtqueue *_vq)
}
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_ctx - get the next used buffer
+ * vring_virtqueue_get_buf_ctx - get the next used buffer
* @_vq: the struct virtqueue we're talking about.
* @len: the length written into the buffer
* @ctx: extra context for the token
@@ -2318,7 +2196,7 @@ EXPORT_SYMBOL_GPL(virtqueue_kick);
* 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,
+static void *vring_virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int
*len,
void **ctx)
{
struct vring_virtqueue *vq = to_vvq(_vq);
@@ -2326,15 +2204,9 @@ void *virtqueue_get_buf_ctx(struct virtqueue *_vq,
unsigned int *len,
return vq->packed_ring ? virtqueue_get_buf_ctx_packed(_vq, len, ctx) :
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
+ * vring_virtqueue_disable_cb - disable callbacks
* @_vq: the struct virtqueue we're talking about.
*
* Note that this is not necessarily synchronous, hence unreliable and only
@@ -2342,7 +2214,7 @@ EXPORT_SYMBOL_GPL(virtqueue_get_buf);
*
* Unlike other operations, this need not be serialized.
*/
-void virtqueue_disable_cb(struct virtqueue *_vq)
+static void vring_virtqueue_disable_cb(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
@@ -2351,10 +2223,9 @@ void virtqueue_disable_cb(struct virtqueue *_vq)
else
virtqueue_disable_cb_split(_vq);
}
-EXPORT_SYMBOL_GPL(virtqueue_disable_cb);
/**
- * virtqueue_enable_cb_prepare - restart callbacks after disable_cb
+ * vring_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
@@ -2365,7 +2236,7 @@ EXPORT_SYMBOL_GPL(virtqueue_disable_cb);
* Caller must ensure we don't call this with other virtqueue
* operations at the same time (except where noted).
*/
-unsigned int virtqueue_enable_cb_prepare(struct virtqueue *_vq)
+static unsigned int vring_virtqueue_enable_cb_prepare(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
@@ -2375,10 +2246,9 @@ unsigned int virtqueue_enable_cb_prepare(struct virtqueue
*_vq)
return vq->packed_ring ? virtqueue_enable_cb_prepare_packed(_vq) :
virtqueue_enable_cb_prepare_split(_vq);
}
-EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare);
/**
- * virtqueue_poll - query pending used buffers
+ * vring_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).
*
@@ -2386,7 +2256,7 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare);
*
* This does not need to be serialized.
*/
-bool virtqueue_poll(struct virtqueue *_vq, unsigned int last_used_idx)
+static bool vring_virtqueue_poll(struct virtqueue *_vq, unsigned int
last_used_idx)
{
struct vring_virtqueue *vq = to_vvq(_vq);
@@ -2397,29 +2267,9 @@ bool virtqueue_poll(struct virtqueue *_vq, unsigned int
last_used_idx)
return vq->packed_ring ? virtqueue_poll_packed(_vq, last_used_idx) :
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 int 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.
+ * vring_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
@@ -2431,7 +2281,7 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb);
* 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)
+static bool vring_virtqueue_enable_cb_delayed(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
@@ -2441,24 +2291,22 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq)
return vq->packed_ring ? virtqueue_enable_cb_delayed_packed(_vq) :
virtqueue_enable_cb_delayed_split(_vq);
}
-EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed);
/**
- * virtqueue_detach_unused_buf - detach first unused buffer
+ * vring_virtqueue_detach_unused_buf - detach first unused buffer
* @_vq: the struct virtqueue we're talking about.
*
* Returns NULL or the "data" token handed to virtqueue_add_*().
* This is not valid on an active queue; it is useful for device
* shutdown or the reset queue.
*/
-void *virtqueue_detach_unused_buf(struct virtqueue *_vq)
+static void *vring_virtqueue_detach_unused_buf(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
return vq->packed_ring ? virtqueue_detach_unused_buf_packed(_vq) :
virtqueue_detach_unused_buf_split(_vq);
}
-EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf);
static inline bool more_used(const struct vring_virtqueue *vq)
{
@@ -2531,6 +2379,7 @@ static struct virtqueue *__vring_new_virtqueue(unsigned
int index,
vq->vq.name = name;
vq->vq.index = index;
vq->vq.reset = false;
+ vq->vq.ops = &vring_ops;
vq->we_own_ring = false;
vq->notify = notify;
vq->weak_barriers = weak_barriers;
@@ -2616,7 +2465,7 @@ struct virtqueue *vring_create_virtqueue_dma(
EXPORT_SYMBOL_GPL(vring_create_virtqueue_dma);
/**
- * virtqueue_resize - resize the vring of vq
+ * vring_virtqueue_resize - resize the vring of vq
* @_vq: the struct virtqueue we're talking about.
* @num: new ring num
* @recycle: callback for recycle the useless buffer
@@ -2639,8 +2488,8 @@ EXPORT_SYMBOL_GPL(vring_create_virtqueue_dma);
* -EPERM: Operation not permitted
*
*/
-int virtqueue_resize(struct virtqueue *_vq, u32 num,
- void (*recycle)(struct virtqueue *vq, void *buf))
+static int vring_virtqueue_resize(struct virtqueue *_vq, u32 num,
+ void (*recycle)(struct virtqueue *vq, void *buf))
{
struct vring_virtqueue *vq = to_vvq(_vq);
struct virtio_device *vdev = vq->vq.vdev;
@@ -2669,7 +2518,7 @@ int virtqueue_resize(struct virtqueue *_vq, u32 num,
if (err)
return err;
- while ((buf = virtqueue_detach_unused_buf(_vq)) != NULL)
+ while ((buf = vring_virtqueue_detach_unused_buf(_vq)) != NULL)
recycle(_vq, buf);
if (vq->packed_ring)
@@ -2682,7 +2531,6 @@ int virtqueue_resize(struct virtqueue *_vq, u32 num,
return err;
}
-EXPORT_SYMBOL_GPL(virtqueue_resize);
/* Only available for split ring */
struct virtqueue *vring_new_virtqueue(unsigned int index,
@@ -2809,20 +2657,19 @@ void vring_transport_features(struct virtio_device
*vdev)
EXPORT_SYMBOL_GPL(vring_transport_features);
/**
- * virtqueue_get_vring_size - return the size of the virtqueue's vring
+ * vring_virtqueue_get_vring_size - return the size of the virtqueue's
vring
* @_vq: the struct virtqueue containing the vring of interest.
*
* Returns the size of the vring. This is mainly used for boasting to
* userspace. Unlike other operations, this need not be serialized.
*/
-unsigned int virtqueue_get_vring_size(const struct virtqueue *_vq)
+static unsigned int vring_virtqueue_get_vring_size(const struct virtqueue *_vq)
{
const struct vring_virtqueue *vq = to_vvq(_vq);
return vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num;
}
-EXPORT_SYMBOL_GPL(virtqueue_get_vring_size);
/*
* This function should only be called by the core, not directly by the driver.
@@ -2848,54 +2695,29 @@ void __virtqueue_unbreak(struct virtqueue *_vq)
}
EXPORT_SYMBOL_GPL(__virtqueue_unbreak);
-bool virtqueue_is_broken(const struct virtqueue *_vq)
+static bool vring_virtqueue_is_broken(const struct virtqueue *_vq)
{
const struct vring_virtqueue *vq = to_vvq(_vq);
return READ_ONCE(vq->broken);
}
-EXPORT_SYMBOL_GPL(virtqueue_is_broken);
-
-/*
- * This should prevent the device from being used, allowing drivers to
- * recover. You may need to grab appropriate locks to flush.
- */
-void virtio_break_device(struct virtio_device *dev)
-{
- struct virtqueue *_vq;
-
- spin_lock(&dev->vqs_list_lock);
- list_for_each_entry(_vq, &dev->vqs, list) {
- struct vring_virtqueue *vq = to_vvq(_vq);
-
- /* Pairs with READ_ONCE() in virtqueue_is_broken(). */
- WRITE_ONCE(vq->broken, true);
- }
- spin_unlock(&dev->vqs_list_lock);
-}
-EXPORT_SYMBOL_GPL(virtio_break_device);
-
-/*
- * This should allow the device to be used by the driver. You may
- * need to grab appropriate locks to flush the write to
- * vq->broken. This should only be used in some specific case e.g
- * (probing and restoring). This function should only be called by the
- * core, not directly by the driver.
- */
-void __virtio_unbreak_device(struct virtio_device *dev)
-{
- struct virtqueue *_vq;
-
- spin_lock(&dev->vqs_list_lock);
- list_for_each_entry(_vq, &dev->vqs, list) {
- struct vring_virtqueue *vq = to_vvq(_vq);
- /* Pairs with READ_ONCE() in virtqueue_is_broken(). */
- WRITE_ONCE(vq->broken, false);
- }
- spin_unlock(&dev->vqs_list_lock);
-}
-EXPORT_SYMBOL_GPL(__virtio_unbreak_device);
+static struct virtqueue_ops vring_ops = {
+ .add_sgs = vring_virtqueue_add_sgs,
+ .kick_prepare = vring_virtqueue_kick_prepare,
+ .notify = vring_virtqueue_notify,
+ .enable_cb_prepare = vring_virtqueue_enable_cb_prepare,
+ .enable_cb_delayed = vring_virtqueue_enable_cb_delayed,
+ .disable_cb = vring_virtqueue_disable_cb,
+ .poll = vring_virtqueue_poll,
+ .get_buf_ctx = vring_virtqueue_get_buf_ctx,
+ .detach_unused_buf = vring_virtqueue_detach_unused_buf,
+ .get_vring_size = vring_virtqueue_get_vring_size,
+ .resize = vring_virtqueue_resize,
+ .__break = __virtqueue_break,
+ .__unbreak = __virtqueue_unbreak,
+ .is_broken = vring_virtqueue_is_broken,
+};
dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *_vq)
{
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index b93238db94e3..845858b8761e 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -10,6 +10,34 @@
#include <linux/mod_devicetable.h>
#include <linux/gfp.h>
+struct virtqueue;
+
+/**
+ * struct virtqueue_ops - abstract operations for a virtqueue.
+ *
+ * Descriptions of each field see the comments in virtio.c
+ */
+struct virtqueue_ops {
+ int (*add_sgs)(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);
+ bool (*kick_prepare)(struct virtqueue *vq);
+ bool (*notify)(struct virtqueue *vq);
+ unsigned int (*enable_cb_prepare)(struct virtqueue *vq);
+ bool (*enable_cb_delayed)(struct virtqueue *vq);
+ void (*disable_cb)(struct virtqueue *vq);
+ bool (*poll)(struct virtqueue *vq, unsigned int idx);
+ void *(*get_buf_ctx)(struct virtqueue *vq, unsigned int *len, void **ctx);
+ void *(*detach_unused_buf)(struct virtqueue *vq);
+ unsigned int (*get_vring_size)(const struct virtqueue *vq);
+ int (*resize)(struct virtqueue *vq, u32 num,
+ void (*recycle)(struct virtqueue *vq, void *buf));
+ void (*__break)(struct virtqueue *vq);
+ void (*__unbreak)(struct virtqueue *vq);
+ bool (*is_broken)(const struct virtqueue *vq);
+};
+
/**
* struct virtqueue - a queue to register buffers for sending or receiving.
* @list: the chain of virtqueues for this device
@@ -36,6 +64,7 @@ struct virtqueue {
unsigned int num_max;
bool reset;
void *priv;
+ struct virtqueue_ops *ops;
};
int virtqueue_add_outbuf(struct virtqueue *vq,
--
2.20.1
Michael S. Tsirkin
2023-May-12 10:46 UTC
[PATCH 1/2] virtio: abstract virtqueue related methods
On Fri, May 12, 2023 at 05:46:17PM +0800, zhenwei pi wrote:> There is already a virtqueue abstract structure in virtio subsystem > (see struct virtqueue in include/linux/virtio.h), however the vring > based virtqueue is used only in the past years, the virtqueue related > methods mix much with vring(just look like the codes, virtqueue_xxx > functions are implemented in virtio_ring.c). > > Abstract virtqueue related methods(see struct virtqueue_ops), and > separate virtqueue_xxx symbols from vring. This allows a non-vring > based transport in the future. With this change, the following symbols > are exported from virtio.ko instead of virtio_ring.ko: > virtqueue_add_sgs > virtqueue_add_outbuf > virtqueue_add_inbuf > virtqueue_add_inbuf_ctx > virtqueue_kick_prepare > virtqueue_notify > virtqueue_kick > virtqueue_enable_cb_prepare > virtqueue_enable_cb > virtqueue_enable_cb_delayed > virtqueue_disable_cb > virtqueue_poll > virtqueue_get_buf_ctx > virtqueue_get_buf > virtqueue_detach_unused_buf > virtqueue_get_vring_size > virtqueue_resize > virtqueue_is_broken > virtio_break_device > __virtio_unbreak_device > > Cc: Stefan Hajnoczi <stefanha at redhat.com> > Signed-off-by: zhenwei pi <pizhenwei at bytedance.com> > --- > drivers/virtio/virtio.c | 362 +++++++++++++++++++++++++++++++++++ > drivers/virtio/virtio_ring.c | 282 +++++---------------------- > include/linux/virtio.h | 29 +++ > 3 files changed, 443 insertions(+), 230 deletions(-) > > diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c > index 3893dc29eb26..8d8715a10f26 100644 > --- a/drivers/virtio/virtio.c > +++ b/drivers/virtio/virtio.c > @@ -553,6 +553,368 @@ int virtio_device_restore(struct virtio_device *dev) > EXPORT_SYMBOL_GPL(virtio_device_restore); > #endif > > +/** > + * virtqueue_add_sgs - expose buffers to other end > + * @vq: the struct virtqueue we're talking about. > + * @sgs: array of terminated scatterlists. > + * @out_sgs: the number of scatterlists readable by other side > + * @in_sgs: 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 vq->ops->add_sgs(vq, sgs, total_sg, out_sgs, in_sgs, > + data, NULL, gfp); > +} > +EXPORT_SYMBOL_GPL(virtqueue_add_sgs);Hmm this kind of indirection on data path is going to be costly performance-wise especially when retpolines are in place. Any data on this?> + > +/** > + * 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 vq->ops->add_sgs(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 vq->ops->add_sgs(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 vq->ops->add_sgs(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 vq->ops->kick_prepare(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) > +{ > + return vq->ops->notify(vq); > +} > +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_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 int virtqueue_enable_cb_prepare(struct virtqueue *vq) > +{ > + return vq->ops->enable_cb_prepare(vq); > +} > +EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare); > + > +/** > + * 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 int val = vq->ops->enable_cb_prepare(vq); > + > + return !vq->ops->poll(vq, val); > +} > +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 vq->ops->enable_cb_delayed(vq); > +} > +EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed); > + > +/** > + * 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) > +{ > + vq->ops->disable_cb(vq); > +} > +EXPORT_SYMBOL_GPL(virtqueue_disable_cb); > + > +/** > + * 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 int idx) > +{ > + return vq->ops->poll(vq, idx); > +} > +EXPORT_SYMBOL_GPL(virtqueue_poll); > + > +/** > + * virtqueue_get_buf_ctx - get the next used buffer > + * @vq: the struct virtqueue we're talking about. > + * @len: the length written into the buffer > + * @ctx: extra context for the token > + * > + * 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 vq->ops->get_buf_ctx(vq, len, ctx); > +} > +EXPORT_SYMBOL_GPL(virtqueue_get_buf_ctx); > + > +void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len) > +{ > + return vq->ops->get_buf_ctx(vq, len, NULL); > +} > +EXPORT_SYMBOL_GPL(virtqueue_get_buf); > + > +/** > + * virtqueue_detach_unused_buf - detach first unused buffer > + * @vq: the struct virtqueue we're talking about. > + * > + * Returns NULL or the "data" token handed to virtqueue_add_*(). > + * This is not valid on an active queue; it is useful for device > + * shutdown or the reset queue. > + */ > +void *virtqueue_detach_unused_buf(struct virtqueue *vq) > +{ > + return vq->ops->detach_unused_buf(vq); > +} > +EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf); > + > +/** > + * virtqueue_get_vring_size - return the size of the virtqueue's vring > + * @vq: the struct virtqueue containing the vring of interest. > + * > + * Returns the size of the vring. This is mainly used for boasting to > + * userspace. Unlike other operations, this need not be serialized. > + */ > +unsigned int virtqueue_get_vring_size(const struct virtqueue *vq) > +{ > + return vq->ops->get_vring_size(vq); > +} > +EXPORT_SYMBOL_GPL(virtqueue_get_vring_size); > + > +/** > + * virtqueue_resize - resize the vring of vq > + * @vq: the struct virtqueue we're talking about. > + * @num: new ring num > + * @recycle: callback for recycle the useless buffer > + * > + * When it is really necessary to create a new vring, it will set the current vq > + * into the reset state. Then call the passed callback to recycle the buffer > + * that is no longer used. Only after the new vring is successfully created, the > + * old vring will be released. > + * > + * 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. > + * 0: success. > + * -ENOMEM: Failed to allocate a new ring, fall back to the original ring size. > + * vq can still work normally > + * -EBUSY: Failed to sync with device, vq may not work properly > + * -ENOENT: Transport or device not supported > + * -E2BIG/-EINVAL: num error > + * -EPERM: Operation not permitted > + * > + */ > +int virtqueue_resize(struct virtqueue *vq, u32 num, > + void (*recycle)(struct virtqueue *vq, void *buf)) > +{ > + if (vq->ops->resize) > + return vq->ops->resize(vq, num, recycle); > + > + return -ENOENT; > +} > +EXPORT_SYMBOL_GPL(virtqueue_resize); > + > +bool virtqueue_is_broken(const struct virtqueue *vq) > +{ > + return vq->ops->is_broken(vq); > +} > +EXPORT_SYMBOL_GPL(virtqueue_is_broken); > + > +/* > + * This should prevent the device from being used, allowing drivers to > + * recover. You may need to grab appropriate locks to flush. > + */ > +void virtio_break_device(struct virtio_device *dev) > +{ > + struct virtqueue *vq; > + > + spin_lock(&dev->vqs_list_lock); > + list_for_each_entry(vq, &dev->vqs, list) { > + vq->ops->__break(vq); > + } > + spin_unlock(&dev->vqs_list_lock); > +} > +EXPORT_SYMBOL_GPL(virtio_break_device); > + > +/* > + * This should allow the device to be used by the driver. You may > + * need to grab appropriate locks to flush the write to > + * vq->broken. This should only be used in some specific case e.g > + * (probing and restoring). This function should only be called by the > + * core, not directly by the driver. > + */ > +void __virtio_unbreak_device(struct virtio_device *dev) > +{ > + struct virtqueue *vq; > + > + spin_lock(&dev->vqs_list_lock); > + list_for_each_entry(vq, &dev->vqs, list) { > + vq->ops->__unbreak(vq); > + } > + spin_unlock(&dev->vqs_list_lock); > +} > +EXPORT_SYMBOL_GPL(__virtio_unbreak_device); > + > static int virtio_init(void) > { > if (bus_register(&virtio_bus) != 0) > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index c5310eaf8b46..7b86417255db 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -227,6 +227,8 @@ static struct virtqueue *__vring_new_virtqueue(unsigned int index, > static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num); > static void vring_free(struct virtqueue *_vq); > > +static struct virtqueue_ops vring_ops; > + > /* > * Helpers. > */ > @@ -2041,6 +2043,7 @@ static struct virtqueue *vring_create_virtqueue_packed( > vq->vq.name = name; > vq->vq.index = index; > vq->vq.reset = false; > + vq->vq.ops = &vring_ops; > vq->we_own_ring = true; > vq->notify = notify; > vq->weak_barriers = weak_barriers; > @@ -2114,17 +2117,17 @@ static int virtqueue_resize_packed(struct virtqueue *_vq, u32 num) > > > /* > - * Generic functions and exported symbols. > + * Vring specific operation functions > */ > > -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) > +static inline int vring_virtqueue_add_sgs(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) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > @@ -2135,110 +2138,7 @@ static inline int virtqueue_add(struct virtqueue *_vq, > } > > /** > - * virtqueue_add_sgs - expose buffers to other end > - * @_vq: the struct virtqueue we're talking about. > - * @sgs: array of terminated scatterlists. > - * @out_sgs: the number of scatterlists readable by other side > - * @in_sgs: 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. > + * vring_virtqueue_kick_prepare - first half of split virtqueue_kick call. > * @_vq: the struct virtqueue > * > * Instead of virtqueue_kick(), you can do: > @@ -2248,24 +2148,23 @@ EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_ctx); > * 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) > +static bool vring_virtqueue_kick_prepare(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > return vq->packed_ring ? virtqueue_kick_prepare_packed(_vq) : > virtqueue_kick_prepare_split(_vq); > } > -EXPORT_SYMBOL_GPL(virtqueue_kick_prepare); > > /** > - * virtqueue_notify - second half of split virtqueue_kick call. > + * vring_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) > +static bool vring_virtqueue_notify(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > @@ -2279,30 +2178,9 @@ bool virtqueue_notify(struct virtqueue *_vq) > } > 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_ctx - get the next used buffer > + * vring_virtqueue_get_buf_ctx - get the next used buffer > * @_vq: the struct virtqueue we're talking about. > * @len: the length written into the buffer > * @ctx: extra context for the token > @@ -2318,7 +2196,7 @@ EXPORT_SYMBOL_GPL(virtqueue_kick); > * 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, > +static void *vring_virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int *len, > void **ctx) > { > struct vring_virtqueue *vq = to_vvq(_vq); > @@ -2326,15 +2204,9 @@ void *virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int *len, > return vq->packed_ring ? virtqueue_get_buf_ctx_packed(_vq, len, ctx) : > 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 > + * vring_virtqueue_disable_cb - disable callbacks > * @_vq: the struct virtqueue we're talking about. > * > * Note that this is not necessarily synchronous, hence unreliable and only > @@ -2342,7 +2214,7 @@ EXPORT_SYMBOL_GPL(virtqueue_get_buf); > * > * Unlike other operations, this need not be serialized. > */ > -void virtqueue_disable_cb(struct virtqueue *_vq) > +static void vring_virtqueue_disable_cb(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > @@ -2351,10 +2223,9 @@ void virtqueue_disable_cb(struct virtqueue *_vq) > else > virtqueue_disable_cb_split(_vq); > } > -EXPORT_SYMBOL_GPL(virtqueue_disable_cb); > > /** > - * virtqueue_enable_cb_prepare - restart callbacks after disable_cb > + * vring_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 > @@ -2365,7 +2236,7 @@ EXPORT_SYMBOL_GPL(virtqueue_disable_cb); > * Caller must ensure we don't call this with other virtqueue > * operations at the same time (except where noted). > */ > -unsigned int virtqueue_enable_cb_prepare(struct virtqueue *_vq) > +static unsigned int vring_virtqueue_enable_cb_prepare(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > @@ -2375,10 +2246,9 @@ unsigned int virtqueue_enable_cb_prepare(struct virtqueue *_vq) > return vq->packed_ring ? virtqueue_enable_cb_prepare_packed(_vq) : > virtqueue_enable_cb_prepare_split(_vq); > } > -EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare); > > /** > - * virtqueue_poll - query pending used buffers > + * vring_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). > * > @@ -2386,7 +2256,7 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare); > * > * This does not need to be serialized. > */ > -bool virtqueue_poll(struct virtqueue *_vq, unsigned int last_used_idx) > +static bool vring_virtqueue_poll(struct virtqueue *_vq, unsigned int last_used_idx) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > @@ -2397,29 +2267,9 @@ bool virtqueue_poll(struct virtqueue *_vq, unsigned int last_used_idx) > return vq->packed_ring ? virtqueue_poll_packed(_vq, last_used_idx) : > 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 int 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. > + * vring_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 > @@ -2431,7 +2281,7 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb); > * 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) > +static bool vring_virtqueue_enable_cb_delayed(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > @@ -2441,24 +2291,22 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) > return vq->packed_ring ? virtqueue_enable_cb_delayed_packed(_vq) : > virtqueue_enable_cb_delayed_split(_vq); > } > -EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed); > > /** > - * virtqueue_detach_unused_buf - detach first unused buffer > + * vring_virtqueue_detach_unused_buf - detach first unused buffer > * @_vq: the struct virtqueue we're talking about. > * > * Returns NULL or the "data" token handed to virtqueue_add_*(). > * This is not valid on an active queue; it is useful for device > * shutdown or the reset queue. > */ > -void *virtqueue_detach_unused_buf(struct virtqueue *_vq) > +static void *vring_virtqueue_detach_unused_buf(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > return vq->packed_ring ? virtqueue_detach_unused_buf_packed(_vq) : > virtqueue_detach_unused_buf_split(_vq); > } > -EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf); > > static inline bool more_used(const struct vring_virtqueue *vq) > { > @@ -2531,6 +2379,7 @@ static struct virtqueue *__vring_new_virtqueue(unsigned int index, > vq->vq.name = name; > vq->vq.index = index; > vq->vq.reset = false; > + vq->vq.ops = &vring_ops; > vq->we_own_ring = false; > vq->notify = notify; > vq->weak_barriers = weak_barriers; > @@ -2616,7 +2465,7 @@ struct virtqueue *vring_create_virtqueue_dma( > EXPORT_SYMBOL_GPL(vring_create_virtqueue_dma); > > /** > - * virtqueue_resize - resize the vring of vq > + * vring_virtqueue_resize - resize the vring of vq > * @_vq: the struct virtqueue we're talking about. > * @num: new ring num > * @recycle: callback for recycle the useless buffer > @@ -2639,8 +2488,8 @@ EXPORT_SYMBOL_GPL(vring_create_virtqueue_dma); > * -EPERM: Operation not permitted > * > */ > -int virtqueue_resize(struct virtqueue *_vq, u32 num, > - void (*recycle)(struct virtqueue *vq, void *buf)) > +static int vring_virtqueue_resize(struct virtqueue *_vq, u32 num, > + void (*recycle)(struct virtqueue *vq, void *buf)) > { > struct vring_virtqueue *vq = to_vvq(_vq); > struct virtio_device *vdev = vq->vq.vdev; > @@ -2669,7 +2518,7 @@ int virtqueue_resize(struct virtqueue *_vq, u32 num, > if (err) > return err; > > - while ((buf = virtqueue_detach_unused_buf(_vq)) != NULL) > + while ((buf = vring_virtqueue_detach_unused_buf(_vq)) != NULL) > recycle(_vq, buf); > > if (vq->packed_ring) > @@ -2682,7 +2531,6 @@ int virtqueue_resize(struct virtqueue *_vq, u32 num, > > return err; > } > -EXPORT_SYMBOL_GPL(virtqueue_resize); > > /* Only available for split ring */ > struct virtqueue *vring_new_virtqueue(unsigned int index, > @@ -2809,20 +2657,19 @@ void vring_transport_features(struct virtio_device *vdev) > EXPORT_SYMBOL_GPL(vring_transport_features); > > /** > - * virtqueue_get_vring_size - return the size of the virtqueue's vring > + * vring_virtqueue_get_vring_size - return the size of the virtqueue's vring > * @_vq: the struct virtqueue containing the vring of interest. > * > * Returns the size of the vring. This is mainly used for boasting to > * userspace. Unlike other operations, this need not be serialized. > */ > -unsigned int virtqueue_get_vring_size(const struct virtqueue *_vq) > +static unsigned int vring_virtqueue_get_vring_size(const struct virtqueue *_vq) > { > > const struct vring_virtqueue *vq = to_vvq(_vq); > > return vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num; > } > -EXPORT_SYMBOL_GPL(virtqueue_get_vring_size); > > /* > * This function should only be called by the core, not directly by the driver. > @@ -2848,54 +2695,29 @@ void __virtqueue_unbreak(struct virtqueue *_vq) > } > EXPORT_SYMBOL_GPL(__virtqueue_unbreak); > > -bool virtqueue_is_broken(const struct virtqueue *_vq) > +static bool vring_virtqueue_is_broken(const struct virtqueue *_vq) > { > const struct vring_virtqueue *vq = to_vvq(_vq); > > return READ_ONCE(vq->broken); > } > -EXPORT_SYMBOL_GPL(virtqueue_is_broken); > - > -/* > - * This should prevent the device from being used, allowing drivers to > - * recover. You may need to grab appropriate locks to flush. > - */ > -void virtio_break_device(struct virtio_device *dev) > -{ > - struct virtqueue *_vq; > - > - spin_lock(&dev->vqs_list_lock); > - list_for_each_entry(_vq, &dev->vqs, list) { > - struct vring_virtqueue *vq = to_vvq(_vq); > - > - /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ > - WRITE_ONCE(vq->broken, true); > - } > - spin_unlock(&dev->vqs_list_lock); > -} > -EXPORT_SYMBOL_GPL(virtio_break_device); > - > -/* > - * This should allow the device to be used by the driver. You may > - * need to grab appropriate locks to flush the write to > - * vq->broken. This should only be used in some specific case e.g > - * (probing and restoring). This function should only be called by the > - * core, not directly by the driver. > - */ > -void __virtio_unbreak_device(struct virtio_device *dev) > -{ > - struct virtqueue *_vq; > - > - spin_lock(&dev->vqs_list_lock); > - list_for_each_entry(_vq, &dev->vqs, list) { > - struct vring_virtqueue *vq = to_vvq(_vq); > > - /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ > - WRITE_ONCE(vq->broken, false); > - } > - spin_unlock(&dev->vqs_list_lock); > -} > -EXPORT_SYMBOL_GPL(__virtio_unbreak_device); > +static struct virtqueue_ops vring_ops = { > + .add_sgs = vring_virtqueue_add_sgs, > + .kick_prepare = vring_virtqueue_kick_prepare, > + .notify = vring_virtqueue_notify, > + .enable_cb_prepare = vring_virtqueue_enable_cb_prepare, > + .enable_cb_delayed = vring_virtqueue_enable_cb_delayed, > + .disable_cb = vring_virtqueue_disable_cb, > + .poll = vring_virtqueue_poll, > + .get_buf_ctx = vring_virtqueue_get_buf_ctx, > + .detach_unused_buf = vring_virtqueue_detach_unused_buf, > + .get_vring_size = vring_virtqueue_get_vring_size, > + .resize = vring_virtqueue_resize, > + .__break = __virtqueue_break, > + .__unbreak = __virtqueue_unbreak, > + .is_broken = vring_virtqueue_is_broken, > +}; > > dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *_vq) > { > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > index b93238db94e3..845858b8761e 100644 > --- a/include/linux/virtio.h > +++ b/include/linux/virtio.h > @@ -10,6 +10,34 @@ > #include <linux/mod_devicetable.h> > #include <linux/gfp.h> > > +struct virtqueue; > + > +/** > + * struct virtqueue_ops - abstract operations for a virtqueue. > + * > + * Descriptions of each field see the comments in virtio.c > + */ > +struct virtqueue_ops { > + int (*add_sgs)(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); > + bool (*kick_prepare)(struct virtqueue *vq); > + bool (*notify)(struct virtqueue *vq); > + unsigned int (*enable_cb_prepare)(struct virtqueue *vq); > + bool (*enable_cb_delayed)(struct virtqueue *vq); > + void (*disable_cb)(struct virtqueue *vq); > + bool (*poll)(struct virtqueue *vq, unsigned int idx); > + void *(*get_buf_ctx)(struct virtqueue *vq, unsigned int *len, void **ctx); > + void *(*detach_unused_buf)(struct virtqueue *vq); > + unsigned int (*get_vring_size)(const struct virtqueue *vq); > + int (*resize)(struct virtqueue *vq, u32 num, > + void (*recycle)(struct virtqueue *vq, void *buf)); > + void (*__break)(struct virtqueue *vq); > + void (*__unbreak)(struct virtqueue *vq); > + bool (*is_broken)(const struct virtqueue *vq); > +}; > + > /** > * struct virtqueue - a queue to register buffers for sending or receiving. > * @list: the chain of virtqueues for this device > @@ -36,6 +64,7 @@ struct virtqueue { > unsigned int num_max; > bool reset; > void *priv; > + struct virtqueue_ops *ops; > }; > > int virtqueue_add_outbuf(struct virtqueue *vq, > -- > 2.20.1
kernel test robot
2023-May-12 16:40 UTC
[PATCH 1/2] virtio: abstract virtqueue related methods
Hi zhenwei,
kernel test robot noticed the following build errors:
[auto build test ERROR on mst-vhost/linux-next]
[also build test ERROR on linus/master v6.4-rc1 next-20230512]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url:
https://github.com/intel-lab-lkp/linux/commits/zhenwei-pi/virtio-abstract-virtqueue-related-methods/20230512-174928
base: https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git linux-next
patch link:
https://lore.kernel.org/r/20230512094618.433707-2-pizhenwei%40bytedance.com
patch subject: [PATCH 1/2] virtio: abstract virtqueue related methods
config: loongarch-allyesconfig
(https://download.01.org/0day-ci/archive/20230513/202305130012.LQ2KTO5C-lkp at
intel.com/config)
compiler: loongarch64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget
https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O
~/bin/make.cross
chmod +x ~/bin/make.cross
#
https://github.com/intel-lab-lkp/linux/commit/372bc1a0371968752fe0f5ec6e81edee6f9c44dd
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review
zhenwei-pi/virtio-abstract-virtqueue-related-methods/20230512-174928
git checkout 372bc1a0371968752fe0f5ec6e81edee6f9c44dd
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1
O=build_dir ARCH=loongarch olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1
O=build_dir ARCH=loongarch SHELL=/bin/bash drivers/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp at intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202305130012.LQ2KTO5C-lkp at
intel.com/
All errors (new ones prefixed by >>):
drivers/virtio/virtio.c: In function
'virtio_break_device':>> drivers/virtio/virtio.c:893:24: error: 'struct virtqueue_ops'
has no member named '__builtin_loongarch_break'
893 | vq->ops->__break(vq);
| ^~
vim +893 drivers/virtio/virtio.c
882
883 /*
884 * This should prevent the device from being used, allowing drivers to
885 * recover. You may need to grab appropriate locks to flush.
886 */
887 void virtio_break_device(struct virtio_device *dev)
888 {
889 struct virtqueue *vq;
890
891 spin_lock(&dev->vqs_list_lock);
892 list_for_each_entry(vq, &dev->vqs, list) {
> 893 vq->ops->__break(vq);
894 }
895 spin_unlock(&dev->vqs_list_lock);
896 }
897 EXPORT_SYMBOL_GPL(virtio_break_device);
898
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests
kernel test robot
2023-May-13 17:22 UTC
[PATCH 1/2] virtio: abstract virtqueue related methods
Hi zhenwei,
kernel test robot noticed the following build warnings:
[auto build test WARNING on mst-vhost/linux-next]
[also build test WARNING on linus/master v6.4-rc1 next-20230512]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url:
https://github.com/intel-lab-lkp/linux/commits/zhenwei-pi/virtio-abstract-virtqueue-related-methods/20230512-174928
base: https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git linux-next
patch link:
https://lore.kernel.org/r/20230512094618.433707-2-pizhenwei%40bytedance.com
patch subject: [PATCH 1/2] virtio: abstract virtqueue related methods
reproduce:
#
https://github.com/intel-lab-lkp/linux/commit/372bc1a0371968752fe0f5ec6e81edee6f9c44dd
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review
zhenwei-pi/virtio-abstract-virtqueue-related-methods/20230512-174928
git checkout 372bc1a0371968752fe0f5ec6e81edee6f9c44dd
make menuconfig
# enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS,
CONFIG_WARN_ABI_ERRORS
make htmldocs
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp at intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202305140142.c0QQq9wZ-lkp at
intel.com/
All warnings (new ones prefixed by >>):
>> ./drivers/virtio/virtio_ring.c:1: warning:
'virtqueue_add_inbuf' not found
>> ./drivers/virtio/virtio_ring.c:1: warning:
'virtqueue_add_outbuf' not found
>> ./drivers/virtio/virtio_ring.c:1: warning: 'virtqueue_add_sgs'
not found
>> ./drivers/virtio/virtio_ring.c:1: warning:
'virtqueue_get_buf_ctx' not found
>> ./drivers/virtio/virtio_ring.c:1: warning:
'virtqueue_disable_cb' not found
>> ./drivers/virtio/virtio_ring.c:1: warning:
'virtqueue_enable_cb' not found
vim +/virtqueue_add_inbuf +1 ./drivers/virtio/virtio_ring.c
fd534e9b5fdcf9 Thomas Gleixner 2019-05-23 @1 // SPDX-License-Identifier:
GPL-2.0-or-later
0a8a69dd77ddbd Rusty Russell 2007-10-22 2 /* Virtio ring
implementation.
0a8a69dd77ddbd Rusty Russell 2007-10-22 3 *
0a8a69dd77ddbd Rusty Russell 2007-10-22 4 * Copyright 2007 Rusty
Russell IBM Corporation
0a8a69dd77ddbd Rusty Russell 2007-10-22 5 */
0a8a69dd77ddbd Rusty Russell 2007-10-22 6 #include
<linux/virtio.h>
0a8a69dd77ddbd Rusty Russell 2007-10-22 7 #include
<linux/virtio_ring.h>
e34f87256794b8 Rusty Russell 2008-07-25 8 #include
<linux/virtio_config.h>
0a8a69dd77ddbd Rusty Russell 2007-10-22 9 #include
<linux/device.h>
5a0e3ad6af8660 Tejun Heo 2010-03-24 10 #include <linux/slab.h>
b5a2c4f1996d1d Paul Gortmaker 2011-07-03 11 #include
<linux/module.h>
e93300b1afc7cd Rusty Russell 2012-01-12 12 #include
<linux/hrtimer.h>
780bc7903a32ed Andy Lutomirski 2016-02-02 13 #include
<linux/dma-mapping.h>
88938359e2dfe1 Alexander Potapenko 2022-09-15 14 #include
<linux/kmsan.h>
f8ce72632fa7ed Michael S. Tsirkin 2021-08-10 15 #include
<linux/spinlock.h>
78fe39872378b0 Andy Lutomirski 2016-02-02 16 #include <xen/xen.h>
0a8a69dd77ddbd Rusty Russell 2007-10-22 17
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests