[src/trunk]: src/sys/external/bsd/drm2/linux drm: Support dma_resv_reserve_sh...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5391605d1238
branches:  trunk
changeset: 1028943:5391605d1238
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sun Dec 19 12:32:53 2021 +0000

description:
drm: Support dma_resv_reserve_shared(..., num_fences>1).

diffstat:

 sys/external/bsd/drm2/linux/linux_dma_resv.c |  21 ++++++++++-----------
 1 files changed, 10 insertions(+), 11 deletions(-)

diffs (64 lines):

diff -r e75e66cbd9c7 -r 5391605d1238 sys/external/bsd/drm2/linux/linux_dma_resv.c
--- a/sys/external/bsd/drm2/linux/linux_dma_resv.c      Sun Dec 19 12:32:45 2021 +0000
+++ b/sys/external/bsd/drm2/linux/linux_dma_resv.c      Sun Dec 19 12:32:53 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: linux_dma_resv.c,v 1.17 2021/12/19 12:31:34 riastradh Exp $    */
+/*     $NetBSD: linux_dma_resv.c,v 1.18 2021/12/19 12:32:53 riastradh Exp $    */
 
 /*-
  * Copyright (c) 2018 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_dma_resv.c,v 1.17 2021/12/19 12:31:34 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_dma_resv.c,v 1.18 2021/12/19 12:32:53 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/poll.h>
@@ -300,10 +300,10 @@
 }
 
 /*
- * dma_resv_reserve_shared(robj)
+ * dma_resv_reserve_shared(robj, num_fences)
  *
- *     Reserve space in robj to add a shared fence.  To be used only
- *     once before calling dma_resv_add_shared_fence.
+ *     Reserve space in robj to add num_fences shared fences.  To be
+ *     used only once before calling dma_resv_add_shared_fence.
  *
  *     Caller must have robj locked.
  *
@@ -317,7 +317,6 @@
        uint32_t n, nalloc;
 
        KASSERT(dma_resv_held(robj));
-       KASSERT(num_fences == 1);
 
        list = robj->fence;
        prealloc = robj->robj_prealloc;
@@ -325,18 +324,18 @@
        /* If there's an existing list, check it for space.  */
        if (list) {
                /* If there's too many already, give up.  */
-               if (list->shared_count == UINT32_MAX)
+               if (list->shared_count > UINT32_MAX - num_fences)
                        return -ENOMEM;
 
-               /* Add one more. */
-               n = list->shared_count + 1;
+               /* Add some more. */
+               n = list->shared_count + num_fences;
 
                /* If there's enough for one more, we're done.  */
                if (n <= list->shared_max)
                        return 0;
        } else {
-               /* No list already.  We need space for 1.  */
-               n = 1;
+               /* No list already.  We need space for num_fences.  */
+               n = num_fences;
        }
 
        /* If not, maybe there's a preallocated list ready.  */