Re: [igt-dev] [PATCH i-g-t] lib/i915: add mmap_offset support

Antonio Argenziano
2019-02-22T22:01:44Z

On 22/02/19 13:59, Antonio Argenziano wrote:
> From: "Kalamarz, Lukasz" <lukasz.kalamarz@intel.com>
>
> With recently proposed changes, IGT need to start supporting new
> way of mmaping object, which will be used from now by default.
> This patch modify gem_mmap_wc and gem_mmap functions to be
> in sync with those changes.
>
> v2:
> - Fix IOCTL number. (Daniele)
> - Move wrappers to new file. (Chris)

Not sure how much of the other stuff we might want to bring over so I've
moved only the new wrappers for now.

Antonio

>
> Signed-off-by: Lukasz Kalamarz <lukasz.kalamarz@intel.com>
> Cc: Janulgue Abdiel <abdiel.janulgue@intel.com>
> Cc: Matthew Auld <matthew.auld@intel.com>
> Cc: Michal Winiarski <michal.winiarski@intel.com>
> Cc: Antonio Argenziano <antonio.argenziano@intel.com>
> Cc: Daniele Spurio Ceraolo <daniele.ceraolospurio@intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Signed-off-by: Antonio Argenziano <antonio.argenziano@intel.com>
> ---
> lib/i915/gem_mman.c | 87 ++++++++++++++++++++++++++++++++++++++++++++
> lib/i915/gem_mman.h | 61 +++++++++++++++++++++++++++++++
> lib/ioctl_wrappers.c | 67 +++++++++++++++++++++++-----------
> lib/ioctl_wrappers.h | 1 +
> lib/meson.build | 1 +
> 5 files changed, 196 insertions(+), 21 deletions(-)
> create mode 100644 lib/i915/gem_mman.c
> create mode 100644 lib/i915/gem_mman.h
>
> diff --git a/lib/i915/gem_mman.c b/lib/i915/gem_mman.c
> new file mode 100644
> index 00000000..fb949f44
> --- /dev/null
> +++ b/lib/i915/gem_mman.c
> @@ -0,0 +1,87 @@
> +/*
> + * Copyright © 2007, 2011, 2013, 2014, 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 <stdbool.h>
> +#include <sys/ioctl.h>
> +
> +#include "igt_core.h"
> +#include "ioctl_wrappers.h"
> +
> +#include "gem_mman.h"
> +
> +
> +bool has_mmap_offset(int fd)
> +{
> + static int has_mmap_offset = -1;
> +
> + if (has_mmap_offset == -1) {
> + struct drm_i915_getparam gp;
> +
> + has_mmap_offset = 0;
> +
> + memset(&gp, 0, sizeof(gp));
> + gp.param = 0x55; /* I915_PARAM_MMAP_OFFSET_VERSION */
> + gp.value = &has_mmap_offset;
> + ioctl(fd, DRM_IOCTL_I915_GETPARAM, &gp);
> + }
> +
> + return has_mmap_offset > 0;
> +}
> +
> +/**
> + * __gem_mmap_offset:
> + * @fd: open i915 drm file descriptor
> + * @handle: gem buffer object handle
> + * @offset: offset in the gem buffer of the mmap arena
> + * @size: size of the mmap arena
> + * @prot: memory protection bits as used by mmap()
> + * @flags: flags used to determine caching
> + *
> + * Similar to __gem_mmap but use MMAP_OFFSET IOCTL.
> + *
> + * Returns: A pointer to the created memory mapping, NULL on failure.
> + */
> +void
> +*__gem_mmap_offset(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned int prot, uint64_t flags)
> +{
> + struct local_drm_i915_gem_mmap_offset arg;
> + void *ptr;
> +
> + memset(&arg, 0, sizeof(arg));
> + arg.handle = handle;
> + arg.offset = offset;
> + arg.flags = flags;
> +
> + if (igt_ioctl(fd, LOCAL_DRM_IOCTL_I915_GEM_MMAP_OFFSET, &arg))
> + return NULL;
> +
> + ptr = mmap64(0, size, prot, MAP_SHARED, fd, arg.offset);
> +
> + if (ptr == MAP_FAILED)
> + ptr = NULL;
> + else
> + errno = 0;
> +
> + return ptr;
> +}
> diff --git a/lib/i915/gem_mman.h b/lib/i915/gem_mman.h
> new file mode 100644
> index 00000000..2f24ca99
> --- /dev/null
> +++ b/lib/i915/gem_mman.h
> @@ -0,0 +1,61 @@
> +/*
> + * Copyright © 2007, 2011, 2013, 2014, 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.
> + *
> + */
> +
> +#ifndef GEM_MMAN_H
> +#define GEM_MMAN_H
> +
> +struct local_drm_i915_gem_mmap_offset {
> + /** Handle for the object being mapped. */
> + __u32 handle;
> + __u32 pad;
> + /**
> + * Fake offset to use for subsequent mmap call
> + *
> + * This is a fixed-size type for 32/64 compatibility.
> + */
> + __u64 offset;
> +
> + /**
> + * Flags for extended behaviour.
> + *
> + * It is mandatory that either one of the _WC/_WB flags
> + * should be passed here.
> + */
> + __u64 flags;
> +};
> +
> +#define LOCAL_DRM_I915_GEM_MMAP_OFFSET 0x24
> +#define LOCAL_I915_MMAP_OFFSET_WC (1 << 0)
> +#define LOCAL_I915_MMAP_OFFSET_WB (1 << 1)
> +#define LOCAL_I915_MMAP_OFFSET_UC (1 << 2)
> +
> +#define LOCAL_DRM_IOCTL_I915_GEM_MMAP_OFFSET \
> + DRM_IOWR(DRM_COMMAND_BASE + LOCAL_DRM_I915_GEM_MMAP_OFFSET, struct local_drm_i915_gem_mmap_offset)
> +
> +bool has_mmap_offset(int fd);
> +
> +void *__gem_mmap_offset(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned int prot, uint64_t flags);
> +
> +#endif /* GEM_MMAN_H */
> +
> diff --git a/lib/ioctl_wrappers.c b/lib/ioctl_wrappers.c
> index 404c2fbf..c11b0146 100644
> --- a/lib/ioctl_wrappers.c
> +++ b/lib/ioctl_wrappers.c
> @@ -707,35 +707,50 @@ bool gem_mmap__has_wc(int fd)
> static int has_wc = -1;
>
> if (has_wc == -1) {
> - struct drm_i915_getparam gp;
> - int mmap_version = -1;
> - int gtt_version = -1;
>
> has_wc = 0;
>
> - memset(&gp, 0, sizeof(gp));
> - gp.param = I915_PARAM_MMAP_GTT_VERSION;
> - gp.value = &gtt_version;
> - ioctl(fd, DRM_IOCTL_I915_GETPARAM, &gp);
> -
> - memset(&gp, 0, sizeof(gp));
> - gp.param = I915_PARAM_MMAP_VERSION;
> - gp.value = &mmap_version;
> - ioctl(fd, DRM_IOCTL_I915_GETPARAM, &gp);
> -
> - /* Do we have the new mmap_ioctl with DOMAIN_WC? */
> - if (mmap_version >= 1 && gtt_version >= 2) {
> - struct drm_i915_gem_mmap arg;
> + /* Do we have the new mmap_offset ioctl? */
> + if (has_mmap_offset(fd)) {
> + struct local_drm_i915_gem_mmap_offset arg;
>
> /* Does this device support wc-mmaps ? */
> memset(&arg, 0, sizeof(arg));
> arg.handle = gem_create(fd, 4096);
> arg.offset = 0;
> - arg.size = 4096;
> - arg.flags = I915_MMAP_WC;
> - has_wc = igt_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &arg) == 0;
> + arg.flags = LOCAL_I915_MMAP_OFFSET_WC;
> + has_wc = igt_ioctl(fd, LOCAL_DRM_IOCTL_I915_GEM_MMAP_OFFSET, &arg) == 0;
> gem_close(fd, arg.handle);
> + } else {
> + struct drm_i915_getparam gp;
> + int mmap_version = -1;
> + int gtt_version = -1;
> +
> + memset(&gp, 0, sizeof(gp));
> + gp.param = I915_PARAM_MMAP_GTT_VERSION;
> + gp.value = &gtt_version;
> + ioctl(fd, DRM_IOCTL_I915_GETPARAM, &gp);
> +
> + memset(&gp, 0, sizeof(gp));
> + gp.param = I915_PARAM_MMAP_VERSION;
> + gp.value = &mmap_version;
> + ioctl(fd, DRM_IOCTL_I915_GETPARAM, &gp);
> +
> + /* Do we have the mmap_ioctl with DOMAIN_WC? */
> + if (mmap_version >= 1 && gtt_version >= 2) {
> + struct drm_i915_gem_mmap arg;
> +
> + /* Does this device support wc-mmaps ? */
> + memset(&arg, 0, sizeof(arg));
> + arg.handle = gem_create(fd, 4096);
> + arg.offset = 0;
> + arg.size = 4096;
> + arg.flags = I915_MMAP_WC;
> + has_wc = igt_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &arg) == 0;
> + gem_close(fd, arg.handle);
> + }
> }
> +
> errno = 0;
> }
>
> @@ -795,7 +810,10 @@ static void
> */
> void *__gem_mmap__wc(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot)
> {
> - return __gem_mmap(fd, handle, offset, size, prot, I915_MMAP_WC);
> + if (has_mmap_offset(fd))
> + return __gem_mmap_offset(fd, handle, offset, size, prot, LOCAL_I915_MMAP_OFFSET_WC);
> + else
> + return __gem_mmap(fd, handle, offset, size, prot, I915_MMAP_WC);
> }
>
> /**
> @@ -832,7 +850,14 @@ void *gem_mmap__wc(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsi
> */
> void *__gem_mmap__cpu(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot)
> {
> - return __gem_mmap(fd, handle, offset, size, prot, 0);
> + void *ptr;
> +
> + if (has_mmap_offset(fd))
> + ptr = __gem_mmap_offset(fd, handle, offset, size, prot, LOCAL_I915_MMAP_OFFSET_WB);
> + else
> + ptr = __gem_mmap(fd, handle, offset, size, prot, 0);
> +
> + return ptr;
> }
>
> /**
> diff --git a/lib/ioctl_wrappers.h b/lib/ioctl_wrappers.h
> index b22b36b0..ff4e7681 100644
> --- a/lib/ioctl_wrappers.h
> +++ b/lib/ioctl_wrappers.h
> @@ -38,6 +38,7 @@
>
> #include "i915/gem_context.h"
> #include "i915/gem_scheduler.h"
> +#include "i915/gem_mman.h"
>
> /**
> * igt_ioctl:
> diff --git a/lib/meson.build b/lib/meson.build
> index dd36f818..0eb5585d 100644
> --- a/lib/meson.build
> +++ b/lib/meson.build
> @@ -4,6 +4,7 @@ lib_sources = [
> 'i915/gem_scheduler.c',
> 'i915/gem_submission.c',
> 'i915/gem_ring.c',
> + 'i915/gem_mman.c',
> 'igt_color_encoding.c',
> 'igt_debugfs.c',
> 'igt_device.c',