#include <linux/slab.h>
#include <linux/module.h>
#include <linux/hrtimer.h>
+#include <linux/kmemleak.h>
#ifdef DEBUG
/* For development, we want to crash whenever the ring is screwed. */
#define END_USE(vq)
#endif
-struct vring_virtqueue
-{
+struct vring_virtqueue {
struct virtqueue vq;
/* Actual memory layout for this queue */
/* Last used index we've seen. */
u16 last_used_idx;
+ /* Last written value to avail->flags */
+ u16 avail_flags_shadow;
+
+ /* Last written value to avail->idx in guest byte order */
+ u16 avail_idx_shadow;
+
/* How to notify other side. FIXME: commonalize hcalls! */
- void (*notify)(struct virtqueue *vq);
+ bool (*notify)(struct virtqueue *vq);
#ifdef DEBUG
/* They're supposed to lock for us. */
#define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq)
-static inline struct scatterlist *sg_next_chained(struct scatterlist *sg,
- unsigned int *count)
-{
- return sg_next(sg);
-}
-
-static inline struct scatterlist *sg_next_arr(struct scatterlist *sg,
- unsigned int *count)
-{
- if (--(*count) == 0)
- return NULL;
- return sg + 1;
-}
-
-/* Set up an indirect table of descriptors and add it to the queue. */
-static inline int vring_add_indirect(struct vring_virtqueue *vq,
- struct scatterlist *sgs[],
- struct scatterlist *(*next)
- (struct scatterlist *, unsigned int *),
- unsigned int total_sg,
- unsigned int total_out,
- unsigned int total_in,
- unsigned int out_sgs,
- unsigned int in_sgs,
- gfp_t gfp)
+static struct vring_desc *alloc_indirect(struct virtqueue *_vq,
+ unsigned int total_sg, gfp_t gfp)
{
struct vring_desc *desc;
- unsigned head;
- struct scatterlist *sg;
- int i, n;
+ unsigned int i;
/*
* We require lowmem mappings for the descriptors because
* otherwise virt_to_phys will give us bogus addresses in the
* virtqueue.
*/
- gfp &= ~(__GFP_HIGHMEM | __GFP_HIGH);
+ gfp &= ~__GFP_HIGHMEM;
desc = kmalloc(total_sg * sizeof(struct vring_desc), gfp);
if (!desc)
- return -ENOMEM;
-
- /* Transfer entries from the sg lists into the indirect page */
- i = 0;
- for (n = 0; n < out_sgs; n++) {
- for (sg = sgs[n]; sg; sg = next(sg, &total_out)) {
- desc[i].flags = VRING_DESC_F_NEXT;
- desc[i].addr = sg_phys(sg);
- desc[i].len = sg->length;
- desc[i].next = i+1;
- i++;
- }
- }
- for (; n < (out_sgs + in_sgs); n++) {
- for (sg = sgs[n]; sg; sg = next(sg, &total_in)) {
- desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
- desc[i].addr = sg_phys(sg);
- desc[i].len = sg->length;
- desc[i].next = i+1;
- i++;
- }
- }
- BUG_ON(i != total_sg);
-
- /* Last one doesn't continue. */
- desc[i-1].flags &= ~VRING_DESC_F_NEXT;
- desc[i-1].next = 0;
-
- /* We're about to use a buffer */
- vq->vq.num_free--;
-
- /* Use a single buffer which doesn't continue */
- head = vq->free_head;
- vq->vring.desc[head].flags = VRING_DESC_F_INDIRECT;
- vq->vring.desc[head].addr = virt_to_phys(desc);
- vq->vring.desc[head].len = i * sizeof(struct vring_desc);
-
- /* Update free pointer */
- vq->free_head = vq->vring.desc[head].next;
+ return NULL;
- return head;
+ for (i = 0; i < total_sg; i++)
+ desc[i].next = cpu_to_virtio16(_vq->vdev, i + 1);
+ return desc;
}
static inline int virtqueue_add(struct virtqueue *_vq,
struct scatterlist *sgs[],
- struct scatterlist *(*next)
- (struct scatterlist *, unsigned int *),
- unsigned int total_out,
- unsigned int total_in,
+ unsigned int total_sg,
unsigned int out_sgs,
unsigned int in_sgs,
void *data,
{
struct vring_virtqueue *vq = to_vvq(_vq);
struct scatterlist *sg;
- unsigned int i, n, avail, uninitialized_var(prev), total_sg;
+ struct vring_desc *desc;
+ unsigned int i, n, avail, descs_used, uninitialized_var(prev);
int head;
+ bool indirect;
START_USE(vq);
BUG_ON(data == NULL);
+ if (unlikely(vq->broken)) {
+ END_USE(vq);
+ return -EIO;
+ }
+
#ifdef DEBUG
{
ktime_t now = ktime_get();
}
#endif
- total_sg = total_in + total_out;
+ BUG_ON(total_sg > vq->vring.num);
+ BUG_ON(total_sg == 0);
+
+ head = vq->free_head;
/* If the host supports indirect descriptor tables, and we have multiple
* buffers, then go indirect. FIXME: tune this threshold */
- if (vq->indirect && total_sg > 1 && vq->vq.num_free) {
- head = vring_add_indirect(vq, sgs, next, total_sg, total_out,
- total_in,
- out_sgs, in_sgs, gfp);
- if (likely(head >= 0))
- goto add_head;
+ if (vq->indirect && total_sg > 1 && vq->vq.num_free)
+ desc = alloc_indirect(_vq, total_sg, gfp);
+ else
+ desc = NULL;
+
+ if (desc) {
+ /* Use a single buffer which doesn't continue */
+ vq->vring.desc[head].flags = cpu_to_virtio16(_vq->vdev, VRING_DESC_F_INDIRECT);
+ vq->vring.desc[head].addr = cpu_to_virtio64(_vq->vdev, virt_to_phys(desc));
+ /* avoid kmemleak false positive (hidden by virt_to_phys) */
+ kmemleak_ignore(desc);
+ vq->vring.desc[head].len = cpu_to_virtio32(_vq->vdev, total_sg * sizeof(struct vring_desc));
+
+ /* Set up rest to use this indirect table. */
+ i = 0;
+ descs_used = 1;
+ indirect = true;
+ } else {
+ desc = vq->vring.desc;
+ i = head;
+ descs_used = total_sg;
+ indirect = false;
}
- BUG_ON(total_sg > vq->vring.num);
- BUG_ON(total_sg == 0);
-
- if (vq->vq.num_free < total_sg) {
+ if (vq->vq.num_free < descs_used) {
pr_debug("Can't add buf len %i - avail = %i\n",
- total_sg, vq->vq.num_free);
+ descs_used, vq->vq.num_free);
/* FIXME: for historical reasons, we force a notify here if
* there are outgoing parts to the buffer. Presumably the
* host should service the ring ASAP. */
}
/* We're about to use some buffers from the free list. */
- vq->vq.num_free -= total_sg;
+ vq->vq.num_free -= descs_used;
- head = i = vq->free_head;
for (n = 0; n < out_sgs; n++) {
- for (sg = sgs[n]; sg; sg = next(sg, &total_out)) {
- vq->vring.desc[i].flags = VRING_DESC_F_NEXT;
- vq->vring.desc[i].addr = sg_phys(sg);
- vq->vring.desc[i].len = sg->length;
+ for (sg = sgs[n]; sg; sg = sg_next(sg)) {
+ desc[i].flags = cpu_to_virtio16(_vq->vdev, VRING_DESC_F_NEXT);
+ desc[i].addr = cpu_to_virtio64(_vq->vdev, sg_phys(sg));
+ desc[i].len = cpu_to_virtio32(_vq->vdev, sg->length);
prev = i;
- i = vq->vring.desc[i].next;
+ i = virtio16_to_cpu(_vq->vdev, desc[i].next);
}
}
for (; n < (out_sgs + in_sgs); n++) {
- for (sg = sgs[n]; sg; sg = next(sg, &total_in)) {
- vq->vring.desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
- vq->vring.desc[i].addr = sg_phys(sg);
- vq->vring.desc[i].len = sg->length;
+ for (sg = sgs[n]; sg; sg = sg_next(sg)) {
+ desc[i].flags = cpu_to_virtio16(_vq->vdev, VRING_DESC_F_NEXT | VRING_DESC_F_WRITE);
+ desc[i].addr = cpu_to_virtio64(_vq->vdev, sg_phys(sg));
+ desc[i].len = cpu_to_virtio32(_vq->vdev, sg->length);
prev = i;
- i = vq->vring.desc[i].next;
+ i = virtio16_to_cpu(_vq->vdev, desc[i].next);
}
}
/* Last one doesn't continue. */
- vq->vring.desc[prev].flags &= ~VRING_DESC_F_NEXT;
+ desc[prev].flags &= cpu_to_virtio16(_vq->vdev, ~VRING_DESC_F_NEXT);
/* Update free pointer */
- vq->free_head = i;
+ if (indirect)
+ vq->free_head = virtio16_to_cpu(_vq->vdev, vq->vring.desc[head].next);
+ else
+ vq->free_head = i;
-add_head:
/* Set token. */
vq->data[head] = data;
/* Put entry in available array (but don't update avail->idx until they
* do sync). */
- avail = (vq->vring.avail->idx & (vq->vring.num-1));
- vq->vring.avail->ring[avail] = head;
+ avail = vq->avail_idx_shadow & (vq->vring.num - 1);
+ vq->vring.avail->ring[avail] = cpu_to_virtio16(_vq->vdev, head);
/* Descriptors and available array need to be set before we expose the
* new available array entries. */
virtio_wmb(vq->weak_barriers);
- vq->vring.avail->idx++;
+ vq->avail_idx_shadow++;
+ vq->vring.avail->idx = cpu_to_virtio16(_vq->vdev, vq->avail_idx_shadow);
vq->num_added++;
+ pr_debug("Added buffer head %i to %p\n", head, vq);
+ END_USE(vq);
+
/* This is very unlikely, but theoretically possible. Kick
* just in case. */
if (unlikely(vq->num_added == (1 << 16) - 1))
virtqueue_kick(_vq);
- pr_debug("Added buffer head %i to %p\n", head, vq);
- END_USE(vq);
-
return 0;
}
-/**
- * virtqueue_add_buf - expose buffer to other end
- * @vq: the struct virtqueue we're talking about.
- * @sg: the description of the buffer(s).
- * @out_num: the number of sg readable by other side
- * @in_num: the number of sg which are writable (after readable ones)
- * @data: the token identifying the buffer.
- * @gfp: how to do memory allocations (if necessary).
- *
- * 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).
- */
-int virtqueue_add_buf(struct virtqueue *_vq,
- struct scatterlist sg[],
- unsigned int out,
- unsigned int in,
- void *data,
- gfp_t gfp)
-{
- struct scatterlist *sgs[2];
-
- sgs[0] = sg;
- sgs[1] = sg + out;
-
- return virtqueue_add(_vq, sgs, sg_next_arr,
- out, in, out ? 1 : 0, in ? 1 : 0, data, gfp);
-}
-EXPORT_SYMBOL_GPL(virtqueue_add_buf);
-
/**
* virtqueue_add_sgs - expose buffers to other end
* @vq: the struct virtqueue we're talking about.
* 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).
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
*/
int virtqueue_add_sgs(struct virtqueue *_vq,
struct scatterlist *sgs[],
void *data,
gfp_t gfp)
{
- unsigned int i, total_out, total_in;
+ unsigned int i, total_sg = 0;
/* Count them first. */
- for (i = total_out = total_in = 0; i < out_sgs; i++) {
- struct scatterlist *sg;
- for (sg = sgs[i]; sg; sg = sg_next(sg))
- total_out++;
- }
- for (; i < out_sgs + in_sgs; i++) {
+ for (i = 0; i < out_sgs + in_sgs; i++) {
struct scatterlist *sg;
for (sg = sgs[i]; sg; sg = sg_next(sg))
- total_in++;
+ total_sg++;
}
- return virtqueue_add(_vq, sgs, sg_next_chained,
- total_out, total_in, out_sgs, in_sgs, data, gfp);
+ return virtqueue_add(_vq, sgs, total_sg, out_sgs, in_sgs, data, gfp);
}
EXPORT_SYMBOL_GPL(virtqueue_add_sgs);
/**
* virtqueue_add_outbuf - expose output buffers to other end
* @vq: the struct virtqueue we're talking about.
- * @sgs: array of scatterlists (need not be terminated!)
- * @num: the number of scatterlists readable by other side
+ * @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).
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
*/
int virtqueue_add_outbuf(struct virtqueue *vq,
- struct scatterlist sg[], unsigned int num,
+ struct scatterlist *sg, unsigned int num,
void *data,
gfp_t gfp)
{
- return virtqueue_add(vq, &sg, sg_next_arr, num, 0, 1, 0, data, gfp);
+ return virtqueue_add(vq, &sg, num, 1, 0, data, gfp);
}
EXPORT_SYMBOL_GPL(virtqueue_add_outbuf);
/**
* virtqueue_add_inbuf - expose input buffers to other end
* @vq: the struct virtqueue we're talking about.
- * @sgs: array of scatterlists (need not be terminated!)
- * @num: the number of scatterlists writable by other side
+ * @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).
+ * Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
*/
int virtqueue_add_inbuf(struct virtqueue *vq,
- struct scatterlist sg[], unsigned int num,
+ struct scatterlist *sg, unsigned int num,
void *data,
gfp_t gfp)
{
- return virtqueue_add(vq, &sg, sg_next_arr, 0, num, 0, 1, data, gfp);
+ return virtqueue_add(vq, &sg, num, 0, 1, data, gfp);
}
EXPORT_SYMBOL_GPL(virtqueue_add_inbuf);
* event. */
virtio_mb(vq->weak_barriers);
- old = vq->vring.avail->idx - vq->num_added;
- new = vq->vring.avail->idx;
+ old = vq->avail_idx_shadow - vq->num_added;
+ new = vq->avail_idx_shadow;
vq->num_added = 0;
#ifdef DEBUG
#endif
if (vq->event) {
- needs_kick = vring_need_event(vring_avail_event(&vq->vring),
+ needs_kick = vring_need_event(virtio16_to_cpu(_vq->vdev, vring_avail_event(&vq->vring)),
new, old);
} else {
- needs_kick = !(vq->vring.used->flags & VRING_USED_F_NO_NOTIFY);
+ needs_kick = !(vq->vring.used->flags & cpu_to_virtio16(_vq->vdev, VRING_USED_F_NO_NOTIFY));
}
END_USE(vq);
return needs_kick;
* @vq: the struct virtqueue
*
* This does not need to be serialized.
+ *
+ * Returns false if host notify failed or queue is broken, otherwise true.
*/
-void virtqueue_notify(struct virtqueue *_vq)
+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. */
- vq->notify(_vq);
+ 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_buf calls, invoke this to kick
+ * 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.
*/
-void virtqueue_kick(struct virtqueue *vq)
+bool virtqueue_kick(struct virtqueue *vq)
{
if (virtqueue_kick_prepare(vq))
- virtqueue_notify(vq);
+ return virtqueue_notify(vq);
+ return true;
}
EXPORT_SYMBOL_GPL(virtqueue_kick);
i = head;
/* Free the indirect table */
- if (vq->vring.desc[i].flags & VRING_DESC_F_INDIRECT)
- kfree(phys_to_virt(vq->vring.desc[i].addr));
+ if (vq->vring.desc[i].flags & cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_INDIRECT))
+ kfree(phys_to_virt(virtio64_to_cpu(vq->vq.vdev, vq->vring.desc[i].addr)));
- while (vq->vring.desc[i].flags & VRING_DESC_F_NEXT) {
- i = vq->vring.desc[i].next;
+ while (vq->vring.desc[i].flags & cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT)) {
+ i = virtio16_to_cpu(vq->vq.vdev, vq->vring.desc[i].next);
vq->vq.num_free++;
}
- vq->vring.desc[i].next = vq->free_head;
+ vq->vring.desc[i].next = cpu_to_virtio16(vq->vq.vdev, vq->free_head);
vq->free_head = head;
/* Plus final descriptor */
vq->vq.num_free++;
static inline bool more_used(const struct vring_virtqueue *vq)
{
- return vq->last_used_idx != vq->vring.used->idx;
+ return vq->last_used_idx != virtio16_to_cpu(vq->vq.vdev, vq->vring.used->idx);
}
/**
* operations at the same time (except where noted).
*
* Returns NULL if there are no used buffers, or the "data" token
- * handed to virtqueue_add_buf().
+ * handed to virtqueue_add_*().
*/
void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len)
{
virtio_rmb(vq->weak_barriers);
last_used = (vq->last_used_idx & (vq->vring.num - 1));
- i = vq->vring.used->ring[last_used].id;
- *len = vq->vring.used->ring[last_used].len;
+ i = virtio32_to_cpu(_vq->vdev, vq->vring.used->ring[last_used].id);
+ *len = virtio32_to_cpu(_vq->vdev, vq->vring.used->ring[last_used].len);
if (unlikely(i >= vq->vring.num)) {
BAD_RING(vq, "id %u out of range\n", i);
/* If we expect an interrupt for the next entry, tell host
* by writing event index and flush out the write before
* the read in the next get_buf call. */
- if (!(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) {
- vring_used_event(&vq->vring) = vq->last_used_idx;
+ if (!(vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) {
+ vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, vq->last_used_idx);
virtio_mb(vq->weak_barriers);
}
{
struct vring_virtqueue *vq = to_vvq(_vq);
- vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
+ if (!(vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) {
+ vq->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
+ vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow);
+ }
+
}
EXPORT_SYMBOL_GPL(virtqueue_disable_cb);
/* Depending on the VIRTIO_RING_F_EVENT_IDX feature, we need to
* either clear the flags bit or point the event index at the next
* entry. Always do both to keep code simple. */
- vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
- vring_used_event(&vq->vring) = last_used_idx = vq->last_used_idx;
+ if (vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) {
+ vq->avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT;
+ vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow);
+ }
+ vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, last_used_idx = vq->last_used_idx);
END_USE(vq);
return last_used_idx;
}
struct vring_virtqueue *vq = to_vvq(_vq);
virtio_mb(vq->weak_barriers);
- return (u16)last_used_idx != vq->vring.used->idx;
+ return (u16)last_used_idx != virtio16_to_cpu(_vq->vdev, vq->vring.used->idx);
}
EXPORT_SYMBOL_GPL(virtqueue_poll);
/* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to
* either clear the flags bit or point the event index at the next
* entry. Always do both to keep code simple. */
- vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
+ if (vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) {
+ vq->avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT;
+ vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow);
+ }
/* TODO: tune this threshold */
- bufs = (u16)(vq->vring.avail->idx - vq->last_used_idx) * 3 / 4;
- vring_used_event(&vq->vring) = vq->last_used_idx + bufs;
+ bufs = (u16)(vq->avail_idx_shadow - vq->last_used_idx) * 3 / 4;
+ vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, vq->last_used_idx + bufs);
virtio_mb(vq->weak_barriers);
- if (unlikely((u16)(vq->vring.used->idx - vq->last_used_idx) > bufs)) {
+ if (unlikely((u16)(virtio16_to_cpu(_vq->vdev, vq->vring.used->idx) - vq->last_used_idx) > bufs)) {
END_USE(vq);
return false;
}
* 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_buf().
+ * Returns NULL or the "data" token handed to virtqueue_add_*().
* This is not valid on an active queue; it is useful only for device
* shutdown.
*/
/* detach_buf clears data, so grab it now. */
buf = vq->data[i];
detach_buf(vq, i);
- vq->vring.avail->idx--;
+ vq->avail_idx_shadow--;
+ vq->vring.avail->idx = cpu_to_virtio16(_vq->vdev, vq->avail_idx_shadow);
END_USE(vq);
return buf;
}
struct virtio_device *vdev,
bool weak_barriers,
void *pages,
- void (*notify)(struct virtqueue *),
+ bool (*notify)(struct virtqueue *),
void (*callback)(struct virtqueue *),
const char *name)
{
vq->weak_barriers = weak_barriers;
vq->broken = false;
vq->last_used_idx = 0;
+ vq->avail_flags_shadow = 0;
+ vq->avail_idx_shadow = 0;
vq->num_added = 0;
list_add_tail(&vq->vq.list, &vdev->vqs);
#ifdef DEBUG
vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX);
/* No callback? Tell other side not to bother us. */
- if (!callback)
- vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
+ if (!callback) {
+ vq->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
+ vq->vring.avail->flags = cpu_to_virtio16(vdev, vq->avail_flags_shadow);
+ }
/* Put everything in free lists. */
vq->free_head = 0;
for (i = 0; i < num-1; i++) {
- vq->vring.desc[i].next = i+1;
+ vq->vring.desc[i].next = cpu_to_virtio16(vdev, i + 1);
vq->data[i] = NULL;
}
vq->data[i] = NULL;
break;
case VIRTIO_RING_F_EVENT_IDX:
break;
+ case VIRTIO_F_VERSION_1:
+ break;
default:
/* We don't understand this bit. */
- clear_bit(i, vdev->features);
+ __virtio_clear_bit(vdev, i);
}
}
}
}
EXPORT_SYMBOL_GPL(virtqueue_get_vring_size);
+bool virtqueue_is_broken(struct virtqueue *_vq)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ return 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;
+
+ list_for_each_entry(_vq, &dev->vqs, list) {
+ struct vring_virtqueue *vq = to_vvq(_vq);
+ vq->broken = true;
+ }
+}
+EXPORT_SYMBOL_GPL(virtio_break_device);
+
+void *virtqueue_get_avail(struct virtqueue *_vq)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ return vq->vring.avail;
+}
+EXPORT_SYMBOL_GPL(virtqueue_get_avail);
+
+void *virtqueue_get_used(struct virtqueue *_vq)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ return vq->vring.used;
+}
+EXPORT_SYMBOL_GPL(virtqueue_get_used);
+
MODULE_LICENSE("GPL");
projects / firefly-linux-kernel-4.4.55.git / blobdiff