[igt-dev] [PATCH i-g-t 3/3] tests/i915/gem_mmap_offset: Add new API test for gem_mmap_offset

[Vanshidhar Konda]

On Mon, Nov 25, 2019 at 10:23:09AM +0000, Chris Wilson wrote:
>Quoting Zbigniew Kempczyński (2019-11-25 10:09:57)
>> From: Lukasz Kalamarz <lukasz.kalamarz at intel.com>
>>
>> Few simple tests which tries to create / mmap buffer objects
>> using GEM_MMAP_OFFSET uAPI.
>>
>> Signed-off-by: Lukasz Kalamarz <lukasz.kalamarz at intel.com>
>> Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski at intel.com>
>> Cc: Chris Wilson <chris at chris-wilson.co.uk>
>> Cc: Vanshidhar Konda <vanshidhar.r.konda at intel.com>
>> ---
>>  tests/Makefile.sources       |   3 +
>>  tests/i915/gem_mmap_offset.c | 127 +++++++++++++++++++++++++++++++++++
>>  tests/meson.build            |   1 +
>>  3 files changed, 131 insertions(+)
>>  create mode 100644 tests/i915/gem_mmap_offset.c
>>
>> diff --git a/tests/Makefile.sources b/tests/Makefile.sources
>> index 27801c89..9c6c3933 100644
>> --- a/tests/Makefile.sources
>> +++ b/tests/Makefile.sources
>> @@ -320,6 +320,9 @@ gem_mmap_SOURCES = i915/gem_mmap.c
>>  TESTS_progs += gem_mmap_gtt
>>  gem_mmap_gtt_SOURCES = i915/gem_mmap_gtt.c
>>
>> +TESTS_progs += gem_mmap_offset
>> +gem_mmap_offset_SOURCES = i915/gem_mmap_offset.c
>> +
>>  TESTS_progs += gem_mmap_offset_exhaustion
>>  gem_mmap_offset_exhaustion_SOURCES = i915/gem_mmap_offset_exhaustion.c
>>
>> diff --git a/tests/i915/gem_mmap_offset.c b/tests/i915/gem_mmap_offset.c
>> new file mode 100644
>> index 00000000..44dca831
>> --- /dev/null
>> +++ b/tests/i915/gem_mmap_offset.c
>> @@ -0,0 +1,127 @@
>> +/*
>> + * Copyright © 2019 Intel Corporation
>> + *
>> + * Permission is hereby granted, free of charge, to any person obtaining a
>> + * copy of this software and associated documentation files (the "Software"),
>> + * to deal in the Software without restriction, including without limitation
>> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
>> + * and/or sell copies of the Software, and to permit persons to whom the
>> + * Software is furnished to do so, subject to the following conditions:
>> + *
>> + * The above copyright notice and this permission notice (including the next
>> + * paragraph) shall be included in all copies or substantial portions of the
>> + * Software.
>> + *
>> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
>> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
>> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
>> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
>> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
>> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
>> + * IN THE SOFTWARE.
>> + */
>> +
>> +#include "igt.h"
>> +#include <errno.h>
>> +#include <sys/stat.h>
>> +#include <sys/ioctl.h>
>> +#include "drm.h"
>> +
>> +IGT_TEST_DESCRIPTION("Basic MMAP_OFFSET IOCTL tests for mem regions\n");
>> +
>> +static int mmap_offset_ioctl(int fd, struct local_i915_gem_mmap_offset *arg)
>> +{
>> +       int err = 0;
>> +
>> +       if (igt_ioctl(fd, LOCAL_IOCTL_I915_GEM_MMAP_OFFSET, arg))
>> +               err = -errno;
>> +
>> +       errno = 0;
>> +       return err;
>> +}
>> +
>> +static void mmap_offset_bad_object(int fd)
>> +{
>> +       uint32_t real_handle;
>> +       uint32_t handles[20];
>> +       int i = 0;
>> +
>> +       real_handle = gem_create(fd, 4096);
>> +
>> +       handles[i++] = 0xdeadbeef;
>> +       for (int bit = 0; bit < 16; bit++)
>> +               handles[i++] = real_handle | (1 << (bit + 16));
>> +       handles[i] = real_handle + 1;
>> +
>> +       for (; i >= 0; i--) {
>> +               struct local_i915_gem_mmap_offset arg = {
>> +                       .handle = handles[i],
>> +                       .flags = LOCAL_I915_MMAP_OFFSET_WC,
>
>Hmm, WC isn't guaranteed on all platforms, neither is GTT, nor may be
>WB, nor UC.
>
>That's quite a conundrum. I would actually say use OFFSET_WB for basic
>API correctness checks as that covers all platforms we have today, and
>we'll cross that bridge when we come to it.

Would doing UC not work across all platforms we have? Since, this code
path should not really be performance sensitive, I thought UC would have
been the safest fall back option.

Vanshi

>-Chris