2022-11-10 17:46:05

by John Keeping

Subject: [PATCH] drm/rockchip: avoid duplicate mappings for IOMMU devices

If a buffer is allocated with alloc_kmap, then it is vmap'd on creation
and there is no reason to map it again in rockchip_gem_prime_vmap() when
the existing mapping can be used.

Signed-off-by: John Keeping <[email protected]>
---
drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
index 6edb7c52cb3d..c9507d27f0ba 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
@@ -519,8 +519,14 @@ int rockchip_gem_prime_vmap(struct drm_gem_object *obj, struct iosys_map *map)
struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);

if (rk_obj->pages) {
- void *vaddr = vmap(rk_obj->pages, rk_obj->num_pages, VM_MAP,
- pgprot_writecombine(PAGE_KERNEL));
+ void *vaddr;
+
+ if (rk_obj->kvaddr)
+ vaddr = rk_obj->kvaddr;
+ else
+ vaddr = vmap(rk_obj->pages, rk_obj->num_pages, VM_MAP,
+ pgprot_writecombine(PAGE_KERNEL));
+
if (!vaddr)
return -ENOMEM;
iosys_map_set_vaddr(map, vaddr);
@@ -540,7 +546,8 @@ void rockchip_gem_prime_vunmap(struct drm_gem_object *obj,
struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);

if (rk_obj->pages) {
- vunmap(map->vaddr);
+ if (map->vaddr != rk_obj->kvaddr)
+ vunmap(map->vaddr);
return;
}

--
2.38.1

2023-02-05 14:56:55

by Heiko Stübner

Subject: Re: [PATCH] drm/rockchip: avoid duplicate mappings for IOMMU devices

On Thu, 10 Nov 2022 17:24:14 +0000, John Keeping wrote:
> If a buffer is allocated with alloc_kmap, then it is vmap'd on creation
> and there is no reason to map it again in rockchip_gem_prime_vmap() when
> the existing mapping can be used.
>
>

Applied, thanks!

[1/1] drm/rockchip: avoid duplicate mappings for IOMMU devices
commit: 0020d4cfa3eea0e5fad23af49411217da854fc83

Best regards,
--
Heiko Stuebner <[email protected]>