xen/gntdev: convert priv->lock to a mutex

Unmapping may require sleeping and we unmap while holding priv->lock, so
convert it to a mutex.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

1 files changed, 20 insertions, 20 deletions

diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index 8cc3f069a10f..3c2534433b30 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -67,7 +67,7 @@ struct gntdev_priv {
          * Only populated if populate_freeable_maps == 1 */
         struct list_head freeable_maps;
         /* lock protects maps and freeable_maps */
-        spinlock_t lock;
+        struct mutex lock;
         struct mm_struct *mm;
         struct mmu_notifier mn;
 };
@@ -221,9 +221,9 @@ static void gntdev_put_map(struct gntdev_priv *priv, struct grant_map *map)
         }
 
         if (populate_freeable_maps && priv) {
-                spin_lock(&priv->lock);
+                mutex_lock(&priv->lock);
                 list_del(&map->next);
-                spin_unlock(&priv->lock);
+                mutex_unlock(&priv->lock);
         }
 
         if (map->pages && !use_ptemod)
@@ -395,9 +395,9 @@ static void gntdev_vma_close(struct vm_area_struct *vma)
                  * not do any unmapping, since that has been done prior to
                  * closing the vma, but it may still iterate the unmap_ops list.
                  */
-                spin_lock(&priv->lock);
+                mutex_lock(&priv->lock);
                 map->vma = NULL;
-                spin_unlock(&priv->lock);
+                mutex_unlock(&priv->lock);
         }
         vma->vm_private_data = NULL;
         gntdev_put_map(priv, map);
@@ -441,14 +441,14 @@ static void mn_invl_range_start(struct mmu_notifier *mn,
         struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn);
         struct grant_map *map;
 
-        spin_lock(&priv->lock);
+        mutex_lock(&priv->lock);
         list_for_each_entry(map, &priv->maps, next) {
                 unmap_if_in_range(map, start, end);
         }
         list_for_each_entry(map, &priv->freeable_maps, next) {
                 unmap_if_in_range(map, start, end);
         }
-        spin_unlock(&priv->lock);
+        mutex_unlock(&priv->lock);
 }
 
 static void mn_invl_page(struct mmu_notifier *mn,
@@ -465,7 +465,7 @@ static void mn_release(struct mmu_notifier *mn,
         struct grant_map *map;
         int err;
 
-        spin_lock(&priv->lock);
+        mutex_lock(&priv->lock);
         list_for_each_entry(map, &priv->maps, next) {
                 if (!map->vma)
                         continue;
@@ -484,7 +484,7 @@ static void mn_release(struct mmu_notifier *mn,
                 err = unmap_grant_pages(map, /* offset */ 0, map->count);
                 WARN_ON(err);
         }
-        spin_unlock(&priv->lock);
+        mutex_unlock(&priv->lock);
 }
 
 static struct mmu_notifier_ops gntdev_mmu_ops = {
@@ -506,7 +506,7 @@ static int gntdev_open(struct inode *inode, struct file *flip)
 
         INIT_LIST_HEAD(&priv->maps);
         INIT_LIST_HEAD(&priv->freeable_maps);
-        spin_lock_init(&priv->lock);
+        mutex_init(&priv->lock);
 
         if (use_ptemod) {
                 priv->mm = get_task_mm(current);
@@ -580,10 +580,10 @@ static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv,
                 return -EFAULT;
         }
 
-        spin_lock(&priv->lock);
+        mutex_lock(&priv->lock);
         gntdev_add_map(priv, map);
         op.index = map->index << PAGE_SHIFT;
-        spin_unlock(&priv->lock);
+        mutex_unlock(&priv->lock);
 
         if (copy_to_user(u, &op, sizeof(op)) != 0)
                 return -EFAULT;
@@ -602,7 +602,7 @@ static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv,
                 return -EFAULT;
         pr_debug("priv %p, del %d+%d\n", priv, (int)op.index, (int)op.count);
 
-        spin_lock(&priv->lock);
+        mutex_lock(&priv->lock);
         map = gntdev_find_map_index(priv, op.index >> PAGE_SHIFT, op.count);
         if (map) {
                 list_del(&map->next);
@@ -610,7 +610,7 @@ static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv,
                         list_add_tail(&map->next, &priv->freeable_maps);
                 err = 0;
         }
-        spin_unlock(&priv->lock);
+        mutex_unlock(&priv->lock);
         if (map)
                 gntdev_put_map(priv, map);
         return err;
@@ -678,7 +678,7 @@ static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u)
         out_flags = op.action;
         out_event = op.event_channel_port;
 
-        spin_lock(&priv->lock);
+        mutex_lock(&priv->lock);
 
         list_for_each_entry(map, &priv->maps, next) {
                 uint64_t begin = map->index << PAGE_SHIFT;
@@ -706,7 +706,7 @@ static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u)
         rc = 0;
 
  unlock_out:
-        spin_unlock(&priv->lock);
+        mutex_unlock(&priv->lock);
 
         /* Drop the reference to the event channel we did not save in the map */
         if (out_flags & UNMAP_NOTIFY_SEND_EVENT)
@@ -756,7 +756,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
         pr_debug("map %d+%d at %lx (pgoff %lx)\n",
                         index, count, vma->vm_start, vma->vm_pgoff);
 
-        spin_lock(&priv->lock);
+        mutex_lock(&priv->lock);
         map = gntdev_find_map_index(priv, index, count);
         if (!map)
                 goto unlock_out;
@@ -791,7 +791,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
                         map->flags |= GNTMAP_readonly;
         }
 
-        spin_unlock(&priv->lock);
+        mutex_unlock(&priv->lock);
 
         if (use_ptemod) {
                 err = apply_to_page_range(vma->vm_mm, vma->vm_start,
@@ -819,11 +819,11 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
         return 0;
 
 unlock_out:
-        spin_unlock(&priv->lock);
+        mutex_unlock(&priv->lock);
         return err;
 
 out_unlock_put:
-        spin_unlock(&priv->lock);
+        mutex_unlock(&priv->lock);
 out_put_map:
         if (use_ptemod)
                 map->vma = NULL;