Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

[sfrench/cifs-2.6.git] / drivers / vhost / vhost.c

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index bac939af8dbb149e4998f18a35f80a12455a52f9..15a216cdd507772bc8bbb2539755250aa8001fce 100644 (file)
--- 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);
        }