1 files changed, 83 insertions, 14 deletions

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index bac939af8dbb..15a216cdd507 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1737,13 +1737,87 @@ static int log_write(void __user *log_base,
         return r;
 }
 
+static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len)
+{
+        struct vhost_umem *umem = vq->umem;
+        struct vhost_umem_node *u;
+        u64 start, end, l, min;
+        int r;
+        bool hit = false;
+
+        while (len) {
+                min = len;
+                /* More than one GPAs can be mapped into a single HVA. So
+                 * iterate all possible umems here to be safe.
+                 */
+                list_for_each_entry(u, &umem->umem_list, link) {
+                        if (u->userspace_addr > hva - 1 + len ||
+                            u->userspace_addr - 1 + u->size < hva)
+                                continue;
+                        start = max(u->userspace_addr, hva);
+                        end = min(u->userspace_addr - 1 + u->size,
+                                  hva - 1 + len);
+                        l = end - start + 1;
+                        r = log_write(vq->log_base,
+                                      u->start + start - u->userspace_addr,
+                                      l);
+                        if (r < 0)
+                                return r;
+                        hit = true;
+                        min = min(l, min);
+                }
+
+                if (!hit)
+                        return -EFAULT;
+
+                len -= min;
+                hva += min;
+        }
+
+        return 0;
+}
+
+static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len)
+{
+        struct iovec iov[64];
+        int i, ret;
+
+        if (!vq->iotlb)
+                return log_write(vq->log_base, vq->log_addr + used_offset, len);
+
+        ret = translate_desc(vq, (uintptr_t)vq->used + used_offset,
+                             len, iov, 64, VHOST_ACCESS_WO);
+        if (ret)
+                return ret;
+
+        for (i = 0; i < ret; i++) {
+                ret = log_write_hva(vq, (uintptr_t)iov[i].iov_base,
+                                    iov[i].iov_len);
+                if (ret)
+                        return ret;
+        }
+
+        return 0;
+}
+
 int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
-                    unsigned int log_num, u64 len)
+                    unsigned int log_num, u64 len, struct iovec *iov, int count)
 {
         int i, r;
 
         /* Make sure data written is seen before log. */
         smp_wmb();
+
+        if (vq->iotlb) {
+                for (i = 0; i < count; i++) {
+                        r = log_write_hva(vq, (uintptr_t)iov[i].iov_base,
+                                          iov[i].iov_len);
+                        if (r < 0)
+                                return r;
+                }
+                return 0;
+        }
+
         for (i = 0; i < log_num; ++i) {
                 u64 l = min(log[i].len, len);
                 r = log_write(vq->log_base, log[i].addr, l);
@@ -1773,9 +1847,8 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq)
                 smp_wmb();
                 /* Log used flag write. */
                 used = &vq->used->flags;
-                log_write(vq->log_base, vq->log_addr +
-                          (used - (void __user *)vq->used),
-                          sizeof vq->used->flags);
+                log_used(vq, (used - (void __user *)vq->used),
+                         sizeof vq->used->flags);
                 if (vq->log_ctx)
                         eventfd_signal(vq->log_ctx, 1);
         }
@@ -1793,9 +1866,8 @@ static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event)
                 smp_wmb();
                 /* Log avail event write */
                 used = vhost_avail_event(vq);
-                log_write(vq->log_base, vq->log_addr +
-                          (used - (void __user *)vq->used),
-                          sizeof *vhost_avail_event(vq));
+                log_used(vq, (used - (void __user *)vq->used),
+                         sizeof *vhost_avail_event(vq));
                 if (vq->log_ctx)
                         eventfd_signal(vq->log_ctx, 1);
         }
@@ -2195,10 +2267,8 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
                 /* Make sure data is seen before log. */
                 smp_wmb();
                 /* Log used ring entry write. */
-                log_write(vq->log_base,
-                          vq->log_addr +
-                           ((void __user *)used - (void __user *)vq->used),
-                          count * sizeof *used);
+                log_used(vq, ((void __user *)used - (void __user *)vq->used),
+                         count * sizeof *used);
         }
         old = vq->last_used_idx;
         new = (vq->last_used_idx += count);
@@ -2240,9 +2310,8 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
                 /* Make sure used idx is seen before log. */
                 smp_wmb();
                 /* Log used index update. */
-                log_write(vq->log_base,
-                          vq->log_addr + offsetof(struct vring_used, idx),
-                          sizeof vq->used->idx);
+                log_used(vq, offsetof(struct vring_used, idx),
+                         sizeof vq->used->idx);
                 if (vq->log_ctx)
                         eventfd_signal(vq->log_ctx, 1);
         }