[v15,12/17] drm/radeon, arm64: untag user pointers in radeon_gem_userptr_ioctl
diff mbox series

Message ID 03fe9d923db75cf72678f3ce103838e67390751a.1557160186.git.andreyknvl@google.com
State New
Headers show
Series
  • arm64: untag user pointers passed to the kernel
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Commit Message

Andrey Konovalov May 6, 2019, 4:30 p.m. UTC
This patch is a part of a series that extends arm64 kernel ABI to allow to
pass tagged user pointers (with the top byte set to something else other
than 0x00) as syscall arguments.

In radeon_gem_userptr_ioctl() an MMU notifier is set up with a (tagged)
userspace pointer. The untagged address should be used so that MMU
notifiers for the untagged address get correctly matched up with the right
BO. This funcation also calls radeon_ttm_tt_pin_userptr(), which uses
provided user pointers for vma lookups, which can only by done with
untagged pointers.

This patch untags user pointers in radeon_gem_userptr_ioctl().

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 drivers/gpu/drm/radeon/radeon_gem.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

Felix Kuehling May 7, 2019, 4:44 p.m. UTC | #1
On 2019-05-06 12:30 p.m., Andrey Konovalov wrote:
> [CAUTION: External Email]
>
> This patch is a part of a series that extends arm64 kernel ABI to allow to
> pass tagged user pointers (with the top byte set to something else other
> than 0x00) as syscall arguments.
>
> In radeon_gem_userptr_ioctl() an MMU notifier is set up with a (tagged)
> userspace pointer. The untagged address should be used so that MMU
> notifiers for the untagged address get correctly matched up with the right
> BO. This funcation also calls radeon_ttm_tt_pin_userptr(), which uses
> provided user pointers for vma lookups, which can only by done with
> untagged pointers.
>
> This patch untags user pointers in radeon_gem_userptr_ioctl().
>
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>


> ---
>   drivers/gpu/drm/radeon/radeon_gem.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c
> index 44617dec8183..90eb78fb5eb2 100644
> --- a/drivers/gpu/drm/radeon/radeon_gem.c
> +++ b/drivers/gpu/drm/radeon/radeon_gem.c
> @@ -291,6 +291,8 @@ int radeon_gem_userptr_ioctl(struct drm_device *dev, void *data,
>          uint32_t handle;
>          int r;
>
> +       args->addr = untagged_addr(args->addr);
> +
>          if (offset_in_page(args->addr | args->size))
>                  return -EINVAL;
>
> --
> 2.21.0.1020.gf2820cf01a-goog
>

Patch
diff mbox series

diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c
index 44617dec8183..90eb78fb5eb2 100644
--- a/drivers/gpu/drm/radeon/radeon_gem.c
+++ b/drivers/gpu/drm/radeon/radeon_gem.c
@@ -291,6 +291,8 @@  int radeon_gem_userptr_ioctl(struct drm_device *dev, void *data,
 	uint32_t handle;
 	int r;
 
+	args->addr = untagged_addr(args->addr);
+
 	if (offset_in_page(args->addr | args->size))
 		return -EINVAL;