drm/ttm: make ttm reservation calls behave like reservation calls

This commit converts the source of the val_seq counter to
the ww_mutex api. The reservation objects are converted later,
because there is still a lockdep splat in nouveau that has to
resolved first.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

3 files changed, 34 insertions, 13 deletions

diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h
index 3cb5d848fb66..0a992b016fe9 100644
--- a/include/drm/ttm/ttm_bo_api.h
+++ b/include/drm/ttm/ttm_bo_api.h
@@ -234,7 +234,7 @@ struct ttm_buffer_object {
         struct list_head ddestroy;
         struct list_head swap;
         struct list_head io_reserve_lru;
-        uint32_t val_seq;
+        unsigned long val_seq;
         bool seq_valid;
 
         /**
diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h
index 9c8dca79808e..ec18c5f3e6e9 100644
--- a/include/drm/ttm/ttm_bo_driver.h
+++ b/include/drm/ttm/ttm_bo_driver.h
@@ -38,6 +38,7 @@
 #include <linux/workqueue.h>
 #include <linux/fs.h>
 #include <linux/spinlock.h>
+#include <linux/reservation.h>
 
 struct ttm_backend_func {
         /**
@@ -778,7 +779,7 @@ extern void ttm_mem_io_unlock(struct ttm_mem_type_manager *man);
  * @bo: A pointer to a struct ttm_buffer_object.
  * @interruptible: Sleep interruptible if waiting.
  * @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
- * @use_sequence: If @bo is already reserved, Only sleep waiting for
+ * @use_ticket: If @bo is already reserved, Only sleep waiting for
  * it to become unreserved if @sequence < (@bo)->sequence.
  *
  * Locks a buffer object for validation. (Or prevents other processes from
@@ -819,7 +820,8 @@ extern void ttm_mem_io_unlock(struct ttm_mem_type_manager *man);
  */
 extern int ttm_bo_reserve(struct ttm_buffer_object *bo,
                           bool interruptible,
-                          bool no_wait, bool use_sequence, uint32_t sequence);
+                          bool no_wait, bool use_ticket,
+                          struct ww_acquire_ctx *ticket);
 
 /**
  * ttm_bo_reserve_slowpath_nolru:
@@ -836,7 +838,7 @@ extern int ttm_bo_reserve(struct ttm_buffer_object *bo,
  */
 extern int ttm_bo_reserve_slowpath_nolru(struct ttm_buffer_object *bo,
                                          bool interruptible,
-                                         uint32_t sequence);
+                                         struct ww_acquire_ctx *ticket);
 
 
 /**
@@ -850,7 +852,8 @@ extern int ttm_bo_reserve_slowpath_nolru(struct ttm_buffer_object *bo,
  * held by us, this function cannot deadlock any more.
  */
 extern int ttm_bo_reserve_slowpath(struct ttm_buffer_object *bo,
-                                   bool interruptible, uint32_t sequence);
+                                   bool interruptible,
+                                   struct ww_acquire_ctx *ticket);
 
 /**
  * ttm_bo_reserve_nolru:
@@ -876,8 +879,8 @@ extern int ttm_bo_reserve_slowpath(struct ttm_buffer_object *bo,
  */
 extern int ttm_bo_reserve_nolru(struct ttm_buffer_object *bo,
                                  bool interruptible,
-                                 bool no_wait, bool use_sequence,
-                                 uint32_t sequence);
+                                 bool no_wait, bool use_ticket,
+                                 struct ww_acquire_ctx *ticket);
 
 /**
  * ttm_bo_unreserve
@@ -889,14 +892,25 @@ extern int ttm_bo_reserve_nolru(struct ttm_buffer_object *bo,
 extern void ttm_bo_unreserve(struct ttm_buffer_object *bo);
 
 /**
- * ttm_bo_unreserve_locked
+ * ttm_bo_unreserve_ticket
+ * @bo: A pointer to a struct ttm_buffer_object.
+ * @ticket: ww_acquire_ctx used for reserving
  *
+ * Unreserve a previous reservation of @bo made with @ticket.
+ */
+extern void ttm_bo_unreserve_ticket(struct ttm_buffer_object *bo,
+                                    struct ww_acquire_ctx *ticket);
+
+/**
+ * ttm_bo_unreserve_locked
  * @bo: A pointer to a struct ttm_buffer_object.
+ * @ticket: ww_acquire_ctx used for reserving, or NULL
  *
- * Unreserve a previous reservation of @bo.
+ * Unreserve a previous reservation of @bo made with @ticket.
  * Needs to be called with struct ttm_bo_global::lru_lock held.
  */
-extern void ttm_bo_unreserve_locked(struct ttm_buffer_object *bo);
+extern void ttm_bo_unreserve_ticket_locked(struct ttm_buffer_object *bo,
+                                           struct ww_acquire_ctx *ticket);
 
 /*
  * ttm_bo_util.c
diff --git a/include/drm/ttm/ttm_execbuf_util.h b/include/drm/ttm/ttm_execbuf_util.h
index 547e19f06e57..ba71ef91f4d5 100644
--- a/include/drm/ttm/ttm_execbuf_util.h
+++ b/include/drm/ttm/ttm_execbuf_util.h
@@ -33,6 +33,7 @@
 
 #include <ttm/ttm_bo_api.h>
 #include <linux/list.h>
+#include <linux/reservation.h>
 
 /**
  * struct ttm_validate_buffer
@@ -57,17 +58,20 @@ struct ttm_validate_buffer {
 /**
  * function ttm_eu_backoff_reservation
  *
+ * @ticket:   ww_acquire_ctx from reserve call
  * @list:     thread private list of ttm_validate_buffer structs.
  *
  * Undoes all buffer validation reservations for bos pointed to by
  * the list entries.
  */
 
-extern void ttm_eu_backoff_reservation(struct list_head *list);
+extern void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
+                                       struct list_head *list);
 
 /**
  * function ttm_eu_reserve_buffers
  *
+ * @ticket:  [out] ww_acquire_ctx returned by call.
  * @list:    thread private list of ttm_validate_buffer structs.
  *
  * Tries to reserve bos pointed to by the list entries for validation.
@@ -90,11 +94,13 @@ extern void ttm_eu_backoff_reservation(struct list_head *list);
  * has failed.
  */
 
-extern int ttm_eu_reserve_buffers(struct list_head *list);
+extern int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
+                                  struct list_head *list);
 
 /**
  * function ttm_eu_fence_buffer_objects.
  *
+ * @ticket:      ww_acquire_ctx from reserve call
  * @list:        thread private list of ttm_validate_buffer structs.
  * @sync_obj:    The new sync object for the buffers.
  *
@@ -104,6 +110,7 @@ extern int ttm_eu_reserve_buffers(struct list_head *list);
  *
  */
 
-extern void ttm_eu_fence_buffer_objects(struct list_head *list, void *sync_obj);
+extern void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket,
+                                        struct list_head *list, void *sync_obj);
 
 #endif