1 files changed, 87 insertions, 46 deletions

diff --git a/drivers/gpu/drm/xe/xe_sync.c b/drivers/gpu/drm/xe/xe_sync.c
index e4c220cf9115..f87276df18f2 100644
--- a/drivers/gpu/drm/xe/xe_sync.c
+++ b/drivers/gpu/drm/xe/xe_sync.c
@@ -12,14 +12,14 @@
 
 #include <drm/drm_print.h>
 #include <drm/drm_syncobj.h>
-#include <drm/xe_drm.h>
+#include <uapi/drm/xe_drm.h>
 
 #include "xe_device_types.h"
 #include "xe_exec_queue.h"
 #include "xe_macros.h"
 #include "xe_sched_job_types.h"
 
-struct user_fence {
+struct xe_user_fence {
 	struct xe_device *xe;
 	struct kref refcount;
 	struct dma_fence_cb cb;
@@ -27,39 +27,45 @@ struct user_fence {
 	struct mm_struct *mm;
 	u64 __user *addr;
 	u64 value;
+	int signalled;
 };
 
 static void user_fence_destroy(struct kref *kref)
 {
-	struct user_fence *ufence = container_of(kref, struct user_fence,
+	struct xe_user_fence *ufence = container_of(kref, struct xe_user_fence,
 						 refcount);
 
 	mmdrop(ufence->mm);
 	kfree(ufence);
 }
 
-static void user_fence_get(struct user_fence *ufence)
+static void user_fence_get(struct xe_user_fence *ufence)
 {
 	kref_get(&ufence->refcount);
 }
 
-static void user_fence_put(struct user_fence *ufence)
+static void user_fence_put(struct xe_user_fence *ufence)
 {
 	kref_put(&ufence->refcount, user_fence_destroy);
 }
 
-static struct user_fence *user_fence_create(struct xe_device *xe, u64 addr,
-					    u64 value)
+static struct xe_user_fence *user_fence_create(struct xe_device *xe, u64 addr,
+					       u64 value)
 {
-	struct user_fence *ufence;
+	struct xe_user_fence *ufence;
+	u64 __user *ptr = u64_to_user_ptr(addr);
+	u64 __maybe_unused prefetch_val;
 
-	ufence = kmalloc(sizeof(*ufence), GFP_KERNEL);
+	if (get_user(prefetch_val, ptr))
+		return ERR_PTR(-EFAULT);
+
+	ufence = kzalloc(sizeof(*ufence), GFP_KERNEL);
 	if (!ufence)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	ufence->xe = xe;
 	kref_init(&ufence->refcount);
-	ufence->addr = u64_to_user_ptr(addr);
+	ufence->addr = ptr;
 	ufence->value = value;
 	ufence->mm = current->mm;
 	mmgrab(ufence->mm);
@@ -69,7 +75,7 @@ static struct user_fence *user_fence_create(struct xe_device *xe, u64 addr,
 
 static void user_fence_worker(struct work_struct *w)
 {
-	struct user_fence *ufence = container_of(w, struct user_fence, worker);
+	struct xe_user_fence *ufence = container_of(w, struct xe_user_fence, worker);
 
 	if (mmget_not_zero(ufence->mm)) {
 		kthread_use_mm(ufence->mm);
@@ -77,13 +83,20 @@ static void user_fence_worker(struct work_struct *w)
 			XE_WARN_ON("Copy to user failed");
 		kthread_unuse_mm(ufence->mm);
 		mmput(ufence->mm);
+	} else {
+		drm_dbg(&ufence->xe->drm, "mmget_not_zero() failed, ufence wasn't signaled\n");
 	}
 
+	/*
+	 * Wake up waiters only after updating the ufence state, allowing the UMD
+	 * to safely reuse the same ufence without encountering -EBUSY errors.
+	 */
+	WRITE_ONCE(ufence->signalled, 1);
 	wake_up_all(&ufence->xe->ufence_wq);
 	user_fence_put(ufence);
 }
 
-static void kick_ufence(struct user_fence *ufence, struct dma_fence *fence)
+static void kick_ufence(struct xe_user_fence *ufence, struct dma_fence *fence)
 {
 	INIT_WORK(&ufence->worker, user_fence_worker);
 	queue_work(ufence->xe->ordered_wq, &ufence->worker);
@@ -92,7 +105,7 @@ static void kick_ufence(struct user_fence *ufence, struct dma_fence *fence)
 
 static void user_fence_cb(struct dma_fence *fence, struct dma_fence_cb *cb)
 {
-	struct user_fence *ufence = container_of(cb, struct user_fence, cb);
+	struct xe_user_fence *ufence = container_of(cb, struct xe_user_fence, cb);
 
 	kick_ufence(ufence, fence);
 }
@@ -181,8 +194,8 @@ int xe_sync_entry_parse(struct xe_device *xe, struct xe_file *xef,
 		} else {
 			sync->ufence = user_fence_create(xe, sync_in.addr,
 							 sync_in.timeline_value);
-			if (XE_IOCTL_DBG(xe, !sync->ufence))
-				return -ENOMEM;
+			if (XE_IOCTL_DBG(xe, IS_ERR(sync->ufence)))
+				return PTR_ERR(sync->ufence);
 		}
 
 		break;
@@ -197,33 +210,18 @@ int xe_sync_entry_parse(struct xe_device *xe, struct xe_file *xef,
 
 	return 0;
 }
-
-int xe_sync_entry_wait(struct xe_sync_entry *sync)
-{
-	if (sync->fence)
-		dma_fence_wait(sync->fence, true);
-
-	return 0;
-}
+ALLOW_ERROR_INJECTION(xe_sync_entry_parse, ERRNO);
 
 int xe_sync_entry_add_deps(struct xe_sync_entry *sync, struct xe_sched_job *job)
 {
-	int err;
-
-	if (sync->fence) {
-		err = drm_sched_job_add_dependency(&job->drm,
-						   dma_fence_get(sync->fence));
-		if (err) {
-			dma_fence_put(sync->fence);
-			return err;
-		}
-	}
+	if (sync->fence)
+		return  drm_sched_job_add_dependency(&job->drm,
+						     dma_fence_get(sync->fence));
 
 	return 0;
 }
 
-void xe_sync_entry_signal(struct xe_sync_entry *sync, struct xe_sched_job *job,
-			  struct dma_fence *fence)
+void xe_sync_entry_signal(struct xe_sync_entry *sync, struct dma_fence *fence)
 {
 	if (!(sync->flags & DRM_XE_SYNC_FLAG_SIGNAL))
 		return;
@@ -252,10 +250,6 @@ void xe_sync_entry_signal(struct xe_sync_entry *sync, struct xe_sched_job *job,
 			user_fence_put(sync->ufence);
 			dma_fence_put(fence);
 		}
-	} else if (sync->type == DRM_XE_SYNC_TYPE_USER_FENCE) {
-		job->user_fence.used = true;
-		job->user_fence.addr = sync->addr;
-		job->user_fence.value = sync->timeline_value;
 	}
 }
 
@@ -263,10 +257,8 @@ void xe_sync_entry_cleanup(struct xe_sync_entry *sync)
 {
 	if (sync->syncobj)
 		drm_syncobj_put(sync->syncobj);
-	if (sync->fence)
-		dma_fence_put(sync->fence);
-	if (sync->chain_fence)
-		dma_fence_put(&sync->chain_fence->base);
+	dma_fence_put(sync->fence);
+	dma_fence_chain_free(sync->chain_fence);
 	if (sync->ufence)
 		user_fence_put(sync->ufence);
 }
@@ -307,7 +299,6 @@ xe_sync_in_fence_get(struct xe_sync_entry *sync, int num_sync,
 	/* Easy case... */
 	if (!num_in_fence) {
 		fence = xe_exec_queue_last_fence_get(q, vm);
-		dma_fence_get(fence);
 		return fence;
 	}
 
@@ -322,7 +313,6 @@ xe_sync_in_fence_get(struct xe_sync_entry *sync, int num_sync,
 		}
 	}
 	fences[current_fence++] = xe_exec_queue_last_fence_get(q, vm);
-	dma_fence_get(fences[current_fence - 1]);
 	cf = dma_fence_array_create(num_in_fence, fences,
 				    vm->composite_fence_ctx,
 				    vm->composite_fence_seqno++,
@@ -342,3 +332,54 @@ err_out:
 
 	return ERR_PTR(-ENOMEM);
 }
+
+/**
+ * __xe_sync_ufence_get() - Get user fence from user fence
+ * @ufence: input user fence
+ *
+ * Get a user fence reference from user fence
+ *
+ * Return: xe_user_fence pointer with reference
+ */
+struct xe_user_fence *__xe_sync_ufence_get(struct xe_user_fence *ufence)
+{
+	user_fence_get(ufence);
+
+	return ufence;
+}
+
+/**
+ * xe_sync_ufence_get() - Get user fence from sync
+ * @sync: input sync
+ *
+ * Get a user fence reference from sync.
+ *
+ * Return: xe_user_fence pointer with reference
+ */
+struct xe_user_fence *xe_sync_ufence_get(struct xe_sync_entry *sync)
+{
+	user_fence_get(sync->ufence);
+
+	return sync->ufence;
+}
+
+/**
+ * xe_sync_ufence_put() - Put user fence reference
+ * @ufence: user fence reference
+ *
+ */
+void xe_sync_ufence_put(struct xe_user_fence *ufence)
+{
+	user_fence_put(ufence);
+}
+
+/**
+ * xe_sync_ufence_get_status() - Get user fence status
+ * @ufence: user fence
+ *
+ * Return: 1 if signalled, 0 not signalled, <0 on error
+ */
+int xe_sync_ufence_get_status(struct xe_user_fence *ufence)
+{
+	return READ_ONCE(ufence->signalled);
+}