drm/ttm: Have the TTM code return -ERESTARTSYS instead of -ERESTART.

Return -ERESTARTSYS instead of -ERESTART when interrupted by a signal.
The -ERESTARTSYS is converted to an -EINTR by the kernel signal layer
before returned to user-space.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

2 files changed, 12 insertions, 24 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 60d8179a8bc..640fb265dd5 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -125,7 +125,7 @@ int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo, bool interruptible)
                 ret = wait_event_interruptible(bo->event_queue,
                                                atomic_read(&bo->reserved) == 0);
                 if (unlikely(ret != 0))
-                        return -ERESTART;
+                        return ret;
         } else {
                 wait_event(bo->event_queue, atomic_read(&bo->reserved) == 0);
         }
@@ -571,7 +571,7 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo, bool interruptible,
         spin_unlock(&bo->lock);
 
         if (unlikely(ret != 0)) {
-                if (ret != -ERESTART) {
+                if (ret != -ERESTARTSYS) {
                         printk(KERN_ERR TTM_PFX
                                "Failed to expire sync object before "
                                "buffer eviction.\n");
@@ -588,7 +588,7 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo, bool interruptible,
         ret = ttm_bo_mem_space(bo, &placement, &evict_mem, interruptible,
                                 no_wait);
         if (ret) {
-                if (ret != -ERESTART)
+                if (ret != -ERESTARTSYS)
                         printk(KERN_ERR TTM_PFX
                                "Failed to find memory space for "
                                "buffer 0x%p eviction.\n", bo);
@@ -598,7 +598,7 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo, bool interruptible,
         ret = ttm_bo_handle_move_mem(bo, &evict_mem, true, interruptible,
                                      no_wait);
         if (ret) {
-                if (ret != -ERESTART)
+                if (ret != -ERESTARTSYS)
                         printk(KERN_ERR TTM_PFX "Buffer eviction failed\n");
                 spin_lock(&glob->lru_lock);
                 if (evict_mem.mm_node) {
@@ -795,7 +795,7 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo,
         uint32_t cur_flags = 0;
         bool type_found = false;
         bool type_ok = false;
-        bool has_eagain = false;
+        bool has_erestartsys = false;
         struct drm_mm_node *node = NULL;
         int i, ret;
 
@@ -882,28 +882,21 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo,
                         mem->mm_node->private = bo;
                         return 0;
                 }
-                if (ret == -ERESTART)
-                        has_eagain = true;
+                if (ret == -ERESTARTSYS)
+                        has_erestartsys = true;
         }
-        ret = (has_eagain) ? -ERESTART : -ENOMEM;
+        ret = (has_erestartsys) ? -ERESTARTSYS : -ENOMEM;
         return ret;
 }
 EXPORT_SYMBOL(ttm_bo_mem_space);
 
 int ttm_bo_wait_cpu(struct ttm_buffer_object *bo, bool no_wait)
 {
-        int ret = 0;
-
         if ((atomic_read(&bo->cpu_writers) > 0) && no_wait)
                 return -EBUSY;
 
-        ret = wait_event_interruptible(bo->event_queue,
-                                       atomic_read(&bo->cpu_writers) == 0);
-
-        if (ret == -ERESTARTSYS)
-                ret = -ERESTART;
-
-        return ret;
+        return wait_event_interruptible(bo->event_queue,
+                                        atomic_read(&bo->cpu_writers) == 0);
 }
 
 int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
@@ -1673,7 +1666,7 @@ int ttm_bo_block_reservation(struct ttm_buffer_object *bo, bool interruptible,
                         ret = wait_event_interruptible
                             (bo->event_queue, atomic_read(&bo->reserved) == 0);
                         if (unlikely(ret != 0))
-                                return -ERESTART;
+                                return ret;
                 } else {
                         wait_event(bo->event_queue,
                                    atomic_read(&bo->reserved) == 0);
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index 1c040d04033..609a85a4d85 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -114,7 +114,7 @@ static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
                 ret = ttm_bo_wait(bo, false, true, false);
                 spin_unlock(&bo->lock);
                 if (unlikely(ret != 0)) {
-                        retval = (ret != -ERESTART) ?
+                        retval = (ret != -ERESTARTSYS) ?
                             VM_FAULT_SIGBUS : VM_FAULT_NOPAGE;
                         goto out_unlock;
                 }
@@ -349,9 +349,6 @@ ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
         switch (ret) {
         case 0:
                 break;
-        case -ERESTART:
-                ret = -EINTR;
-                goto out_unref;
         case -EBUSY:
                 ret = -EAGAIN;
                 goto out_unref;
@@ -421,8 +418,6 @@ ssize_t ttm_bo_fbdev_io(struct ttm_buffer_object *bo, const char __user *wbuf,
         switch (ret) {
         case 0:
                 break;
-        case -ERESTART:
-                return -EINTR;
         case -EBUSY:
                 return -EAGAIN;
         default: