[PATCH v2 6/9] drm/xe: Add xe_migrate_job_lock/unlock helpers

[Matthew Brost]

Add xe_migrate_job_lock/unlock helpers is used ensure ordering when
issuing GT TLB invalidation jobs.

v2:
 - Fix multi-line comments (checkpatch)

Signed-off-by: Matthew Brost <matthew.brost at intel.com>
---
 drivers/gpu/drm/xe/xe_migrate.c | 36 +++++++++++++++++++++++++++++++++
 drivers/gpu/drm/xe/xe_migrate.h |  4 ++++
 2 files changed, 40 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index b5f85162b9ed..1f57adcbb535 100644
--- a/drivers/gpu/drm/xe/xe_migrate.c
+++ b/drivers/gpu/drm/xe/xe_migrate.c
@@ -1917,6 +1917,42 @@ int xe_migrate_access_memory(struct xe_migrate *m, struct xe_bo *bo,
 	return IS_ERR(fence) ? PTR_ERR(fence) : 0;
 }
 
+/**
+ * xe_migrate_job_lock() - Lock migrate job lock
+ * @m: The migration context.
+ * @q: Queue associated with the operation which requires a lock
+ *
+ * Lock the migrate job lock if the queue is a migration queue, otherwise
+ * assert the VM's dma-resv is held (user queue's have own locking).
+ */
+void xe_migrate_job_lock(struct xe_migrate *m, struct xe_exec_queue *q)
+{
+	bool is_migrate = q == m->q;
+
+	if (is_migrate)
+		mutex_lock(&m->job_mutex);
+	else
+		xe_vm_assert_held(q->vm);	/* User queues VM's should be locked */
+}
+
+/**
+ * xe_migrate_job_unlock() - Unlock migrate job lock
+ * @m: The migration context.
+ * @q: Queue associated with the operation which requires a lock
+ *
+ * Unlock the migrate job lock if the queue is a migration queue, otherwise
+ * assert the VM's dma-resv is held (user queue's have own locking).
+ */
+void xe_migrate_job_unlock(struct xe_migrate *m, struct xe_exec_queue *q)
+{
+	bool is_migrate = q == m->q;
+
+	if (is_migrate)
+		mutex_unlock(&m->job_mutex);
+	else
+		xe_vm_assert_held(q->vm);	/* User queues VM's should be locked */
+}
+
 #if IS_ENABLED(CONFIG_DRM_XE_KUNIT_TEST)
 #include "tests/xe_migrate.c"
 #endif
diff --git a/drivers/gpu/drm/xe/xe_migrate.h b/drivers/gpu/drm/xe/xe_migrate.h
index fb9839c1bae0..e9d83d320f8c 100644
--- a/drivers/gpu/drm/xe/xe_migrate.h
+++ b/drivers/gpu/drm/xe/xe_migrate.h
@@ -134,4 +134,8 @@ xe_migrate_update_pgtables(struct xe_migrate *m,
 void xe_migrate_wait(struct xe_migrate *m);
 
 struct xe_exec_queue *xe_tile_migrate_exec_queue(struct xe_tile *tile);
+
+void xe_migrate_job_lock(struct xe_migrate *m, struct xe_exec_queue *q);
+void xe_migrate_job_unlock(struct xe_migrate *m, struct xe_exec_queue *q);
+
 #endif
-- 
2.34.1