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>

4 files changed, 23 insertions, 35 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 60d8179a8bcd..640fb265dd5a 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 1c040d040338..609a85a4d855 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:
diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h
index 2f7f56da2147..4fd498523ce3 100644
--- a/include/drm/ttm/ttm_bo_api.h
+++ b/include/drm/ttm/ttm_bo_api.h
@@ -303,7 +303,7 @@ ttm_bo_reference(struct ttm_buffer_object *bo)
  * Note: It might be necessary to block validations before the
  * wait by reserving the buffer.
  * Returns -EBUSY if no_wait is true and the buffer is busy.
- * Returns -ERESTART if interrupted by a signal.
+ * Returns -ERESTARTSYS if interrupted by a signal.
  */
 extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy,
                        bool interruptible, bool no_wait);
@@ -321,7 +321,7 @@ extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy,
  * -EINVAL on invalid proposed placement.
  * -ENOMEM on out-of-memory condition.
  * -EBUSY if no_wait is true and buffer busy.
- * -ERESTART if interrupted by a signal.
+ * -ERESTARTSYS if interrupted by a signal.
  */
 extern int ttm_buffer_object_validate(struct ttm_buffer_object *bo,
                                         struct ttm_placement *placement,
@@ -347,7 +347,7 @@ extern void ttm_bo_unref(struct ttm_buffer_object **bo);
  * waiting for buffer idle. This lock is recursive.
  * Returns
  * -EBUSY if the buffer is busy and no_wait is true.
- * -ERESTART if interrupted by a signal.
+ * -ERESTARTSYS if interrupted by a signal.
  */
 
 extern int
@@ -390,7 +390,7 @@ extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo);
  * Returns
  * -ENOMEM: Out of memory.
  * -EINVAL: Invalid placement flags.
- * -ERESTART: Interrupted by signal while sleeping waiting for resources.
+ * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
  */
 
 extern int ttm_buffer_object_init(struct ttm_bo_device *bdev,
@@ -430,7 +430,7 @@ extern int ttm_buffer_object_init(struct ttm_bo_device *bdev,
  * Returns
  * -ENOMEM: Out of memory.
  * -EINVAL: Invalid placement flags.
- * -ERESTART: Interrupted by signal while waiting for resources.
+ * -ERESTARTSYS: Interrupted by signal while waiting for resources.
  */
 
 extern int ttm_buffer_object_create(struct ttm_bo_device *bdev,
@@ -521,7 +521,7 @@ extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type);
  *
  * Returns:
  * -EINVAL: Invalid or uninitialized memory type.
- * -ERESTART: The call was interrupted by a signal while waiting to
+ * -ERESTARTSYS: The call was interrupted by a signal while waiting to
  * evict a buffer.
  */
 
@@ -624,7 +624,7 @@ extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
  * be called from the fops::read and fops::write method.
  * Returns:
  * See man (2) write, man(2) read. In particular,
- * the function may return -EINTR if
+ * the function may return -ERESTARTSYS if
  * interrupted by a signal.
  */
 
diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h
index fa5c9e51ee7e..ff7664e0c3cd 100644
--- a/include/drm/ttm/ttm_bo_driver.h
+++ b/include/drm/ttm/ttm_bo_driver.h
@@ -638,7 +638,7 @@ extern bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev,
  * -EBUSY: No space available (only if no_wait == 1).
  * -ENOMEM: Could not allocate memory for the buffer object, either due to
  * fragmentation or concurrent allocators.
- * -ERESTART: An interruptible sleep was interrupted by a signal.
+ * -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
  */
 extern int ttm_bo_mem_space(struct ttm_buffer_object *bo,
                                 struct ttm_placement *placement,
@@ -653,7 +653,7 @@ extern int ttm_bo_mem_space(struct ttm_buffer_object *bo,
  * Wait until a buffer object is no longer sync'ed for CPU access.
  * Returns:
  * -EBUSY: Buffer object was sync'ed for CPU access. (only if no_wait == 1).
- * -ERESTART: An interruptible sleep was interrupted by a signal.
+ * -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
  */
 
 extern int ttm_bo_wait_cpu(struct ttm_buffer_object *bo, bool no_wait);
@@ -757,7 +757,7 @@ extern void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo);
  * -EAGAIN: The reservation may cause a deadlock.
  * Release all buffer reservations, wait for @bo to become unreserved and
  * try again. (only if use_sequence == 1).
- * -ERESTART: A wait for the buffer to become unreserved was interrupted by
+ * -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
  * a signal. Release all buffer reservations and return to user-space.
  */
 extern int ttm_bo_reserve(struct ttm_buffer_object *bo,
@@ -798,7 +798,7 @@ extern int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo,
  *
  * Returns:
  * -EBUSY: If no_wait == 1 and the buffer is already reserved.
- * -ERESTART: If interruptible == 1 and the process received a signal
+ * -ERESTARTSYS: If interruptible == 1 and the process received a signal
  * while sleeping.
  */
 extern int ttm_bo_block_reservation(struct ttm_buffer_object *bo,