[igt-dev] [PATCH i-g-t 2/2] lib/i915: Add mmap_offset support

Antonio Argenziano
2019-02-26T00:20:24Z

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)

v3:
- Use mmap IOCTL for lowr level wrappers. (Chris)

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 | 125 ++++++++++++++++++++++++++++++++++++--------
lib/i915/gem_mman.h | 33 ++++++++++++
2 files changed, 136 insertions(+), 22 deletions(-)

diff --git a/lib/i915/gem_mman.c b/lib/i915/gem_mman.c
index 3cf9a6bb..f89d389e 100644
--- a/lib/i915/gem_mman.c
+++ b/lib/i915/gem_mman.c
@@ -106,36 +106,51 @@ 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;
+
+ errno = 0;
}

return has_wc > 0;
@@ -211,7 +226,12 @@ void *__gem_mmap__wc(int fd, uint32_t handle, uint64_t offset, uint64_t size, un
*/
void *gem_mmap__wc(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot)
{
- void *ptr = __gem_mmap__wc(fd, handle, offset, size, prot);
+ void *ptr;
+
+ ptr = __gem_mmap_offset(fd, handle, offset, size, prot, LOCAL_I915_MMAP_OFFSET_WC);
+ if (!ptr)
+ ptr = __gem_mmap__wc(fd, handle, offset, size, prot);
+
igt_assert(ptr);
return ptr;
}
@@ -248,7 +268,68 @@ void *__gem_mmap__cpu(int fd, uint32_t handle, uint64_t offset, uint64_t size, u
*/
void *gem_mmap__cpu(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot)
{
- void *ptr = __gem_mmap__cpu(fd, handle, offset, size, prot);
+ void *ptr;
+
+ ptr = __gem_mmap_offset(fd, handle, offset, size, prot, LOCAL_I915_MMAP_OFFSET_WB);
+ if (!ptr)
+ ptr = __gem_mmap(fd, handle, offset, size, prot, 0);
+
igt_assert(ptr);
return ptr;
}
+
+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
index f7242ed7..c2c10249 100644
--- a/lib/i915/gem_mman.h
+++ b/lib/i915/gem_mman.h
@@ -51,5 +51,38 @@ int gem_munmap(void *ptr, uint64_t size);
*/
#define gem_require_mmap_wc(fd) igt_require(gem_mmap__has_wc(fd))

+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 */

--
2.20.1