From bfe2bc512884d0b1c5297a15350f940ca80e439b Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Thu, 23 Jun 2016 02:04:30 -0400 Subject: [PATCH] vhost: introduce vhost memory accessors This patch introduces vhost memory accessors which were just wrappers for userspace address access helpers. This is a requirement for vhost device iotlb implementation which will add iotlb translations in those accessors. Signed-off-by: Jason Wang Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 50 ++++++++++++++++++++++++++++++------------- 1 file changed, 35 insertions(+), 15 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 0061a7bd85f6..e1b5047d8f19 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -638,6 +638,22 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, return 1; } +#define vhost_put_user(vq, x, ptr) __put_user(x, ptr) + +static int vhost_copy_to_user(struct vhost_virtqueue *vq, void *to, + const void *from, unsigned size) +{ + return __copy_to_user(to, from, size); +} + +#define vhost_get_user(vq, x, ptr) __get_user(x, ptr) + +static int vhost_copy_from_user(struct vhost_virtqueue *vq, void *to, + void *from, unsigned size) +{ + return __copy_from_user(to, from, size); +} + static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, struct vring_desc __user *desc, struct vring_avail __user *avail, @@ -1143,7 +1159,8 @@ EXPORT_SYMBOL_GPL(vhost_log_write); static int vhost_update_used_flags(struct vhost_virtqueue *vq) { void __user *used; - if (__put_user(cpu_to_vhost16(vq, vq->used_flags), &vq->used->flags) < 0) + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), + &vq->used->flags) < 0) return -EFAULT; if (unlikely(vq->log_used)) { /* Make sure the flag is seen before log. */ @@ -1161,7 +1178,8 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq) static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event) { - if (__put_user(cpu_to_vhost16(vq, vq->avail_idx), vhost_avail_event(vq))) + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), + vhost_avail_event(vq))) return -EFAULT; if (unlikely(vq->log_used)) { void __user *used; @@ -1199,7 +1217,7 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq) r = -EFAULT; goto err; } - r = __get_user(last_used_idx, &vq->used->idx); + r = vhost_get_user(vq, last_used_idx, &vq->used->idx); if (r) goto err; vq->last_used_idx = vhost16_to_cpu(vq, last_used_idx); @@ -1379,7 +1397,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* Check it isn't doing very strange things with descriptor numbers. */ last_avail_idx = vq->last_avail_idx; - if (unlikely(__get_user(avail_idx, &vq->avail->idx))) { + if (unlikely(vhost_get_user(vq, avail_idx, &vq->avail->idx))) { vq_err(vq, "Failed to access avail idx at %p\n", &vq->avail->idx); return -EFAULT; @@ -1401,8 +1419,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* Grab the next descriptor number they're advertising, and increment * the index we've seen. */ - if (unlikely(__get_user(ring_head, - &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { + if (unlikely(vhost_get_user(vq, ring_head, + &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { vq_err(vq, "Failed to read head: idx %d address %p\n", last_avail_idx, &vq->avail->ring[last_avail_idx % vq->num]); @@ -1437,7 +1455,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, i, vq->num, head); return -EINVAL; } - ret = __copy_from_user(&desc, vq->desc + i, sizeof desc); + ret = vhost_copy_from_user(vq, &desc, vq->desc + i, + sizeof desc); if (unlikely(ret)) { vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", i, vq->desc + i); @@ -1525,15 +1544,15 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq, start = vq->last_used_idx & (vq->num - 1); used = vq->used->ring + start; if (count == 1) { - if (__put_user(heads[0].id, &used->id)) { + if (vhost_put_user(vq, heads[0].id, &used->id)) { vq_err(vq, "Failed to write used id"); return -EFAULT; } - if (__put_user(heads[0].len, &used->len)) { + if (vhost_put_user(vq, heads[0].len, &used->len)) { vq_err(vq, "Failed to write used len"); return -EFAULT; } - } else if (__copy_to_user(used, heads, count * sizeof *used)) { + } else if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) { vq_err(vq, "Failed to write used"); return -EFAULT; } @@ -1577,7 +1596,8 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, /* Make sure buffer is written before we update index. */ smp_wmb(); - if (__put_user(cpu_to_vhost16(vq, vq->last_used_idx), &vq->used->idx)) { + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), + &vq->used->idx)) { vq_err(vq, "Failed to increment used idx"); return -EFAULT; } @@ -1609,7 +1629,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { __virtio16 flags; - if (__get_user(flags, &vq->avail->flags)) { + if (vhost_get_user(vq, flags, &vq->avail->flags)) { vq_err(vq, "Failed to get flags"); return true; } @@ -1623,7 +1643,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (unlikely(!v)) return true; - if (__get_user(event, vhost_used_event(vq))) { + if (vhost_get_user(vq, event, vhost_used_event(vq))) { vq_err(vq, "Failed to get used event idx"); return true; } @@ -1665,7 +1685,7 @@ bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq) __virtio16 avail_idx; int r; - r = __get_user(avail_idx, &vq->avail->idx); + r = vhost_get_user(vq, avail_idx, &vq->avail->idx); if (r) return false; @@ -1700,7 +1720,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) /* They could have slipped one in as we were doing that: make * sure it's written, then check again. */ smp_mb(); - r = __get_user(avail_idx, &vq->avail->idx); + r = vhost_get_user(vq, avail_idx, &vq->avail->idx); if (r) { vq_err(vq, "Failed to check avail idx at %p: %d\n", &vq->avail->idx, r); -- 2.20.1