[igt-dev] [PATCH i-g-t 2/6] lib/ioctl_wrapper: Implement __gem_mmap
Lukasz Kalamarz
lukasz.kalamarz at intel.com
Wed Jan 9 17:40:53 UTC 2019
Previous implementation of __gem_mmap__cpu and __gem_mmap_wc only
differ with setting proper flag for caching. This patch implement __gem_mmap
which merge those two functions into one wrapper.
Small documentation modification are add to be in par with new implementation.
Signed-off-by: Lukasz Kalamarz <lukasz.kalamarz at intel.com>
Cc: Michal Winiarski <michal.winiarski at intel.com>
Cc: Katarzyna Dec <katarzyna.dec at intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
---
lib/ioctl_wrappers.c | 96 +++++++++++++++++++++++++++++++-------------
lib/ioctl_wrappers.h | 1 +
2 files changed, 68 insertions(+), 29 deletions(-)
diff --git a/lib/ioctl_wrappers.c b/lib/ioctl_wrappers.c
index f71f0e32..87744edc 100644
--- a/lib/ioctl_wrappers.c
+++ b/lib/ioctl_wrappers.c
@@ -736,6 +736,45 @@ bool gem_mmap__has_wc(int fd)
return has_wc > 0;
}
+/**
+ * __gem_mmap:
+ * @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()
+ * @wc: flag marking if we want to set up MMAP_WC flag
+ *
+ * This functions wraps up procedure to establish a memory mapping through
+ * direct cpu access, bypassing the gpu (valid for wc == false). For wc == true
+ * it also bypass cpu caches completely and GTT system agent (i.e. there is no
+ * automatic tiling of the mmapping through the fence registers).
+ *
+ * Returns: A pointer to the created memory mapping, NULL on failure.
+ */
+void *__gem_mmap(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot, bool wc)
+{
+ struct drm_i915_gem_mmap arg;
+
+ if (wc & !gem_mmap__has_wc(fd)) {
+ errno = ENOSYS;
+ return NULL;
+ }
+
+ memset(&arg, 0, sizeof(arg));
+ arg.handle = handle;
+ arg.offset = offset;
+ arg.size = size;
+ arg.flags = wc ? I915_MMAP_WC : 0;
+ if (igt_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &arg))
+ return NULL;
+
+ VG(VALGRIND_MAKE_MEM_DEFINED(from_user_pointer(arg.addr_ptr), arg.size));
+
+ errno = 0;
+ return from_user_pointer(arg.addr_ptr);
+}
+
/**
* __gem_mmap__wc:
* @fd: open i915 drm file descriptor
@@ -753,25 +792,20 @@ bool gem_mmap__has_wc(int fd)
*/
void *__gem_mmap__wc(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot)
{
- struct drm_i915_gem_mmap arg;
+ struct drm_i915_gem_mmap mmap_arg;
- if (!gem_mmap__has_wc(fd)) {
- errno = ENOSYS;
- return NULL;
- }
+ memset(&mmap_arg, 0, sizeof(mmap_arg));
+ mmap_arg.handle = handle;
+ mmap_arg.offset = offset;
+ mmap_arg.size = size;
+ mmap_arg.flags = I915_MMAP_WC;
+ if (igt_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &mmap_arg))
+ return NULL;
- memset(&arg, 0, sizeof(arg));
- arg.handle = handle;
- arg.offset = offset;
- arg.size = size;
- arg.flags = I915_MMAP_WC;
- if (igt_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &arg))
- return NULL;
+ VG(VALGRIND_MAKE_MEM_DEFINED(from_user_pointer(mmap_arg.addr_ptr), mmap_arg.size));
- VG(VALGRIND_MAKE_MEM_DEFINED(from_user_pointer(arg.addr_ptr), arg.size));
-
- errno = 0;
- return from_user_pointer(arg.addr_ptr);
+ errno = 0;
+ return from_user_pointer(mmap_arg.addr_ptr);
}
/**
@@ -782,13 +816,16 @@ void *__gem_mmap__wc(int fd, uint32_t handle, uint64_t offset, uint64_t size, un
* @size: size of the mmap arena
* @prot: memory protection bits as used by mmap()
*
- * Like __gem_mmap__wc() except we assert on failure.
+ * This functions wraps up procedure to establish a memory mapping through
+ * direct cpu access, bypassing the gpu and cpu caches completely and also
+ * bypassing the GTT system agent (i.e. there is no automatic tiling of
+ * the mmapping through the fence registers).We assert on failure.
*
* Returns: A pointer to the created memory mapping
*/
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 = __gem_mmap(fd, handle, offset, size, prot, true);
igt_assert(ptr);
return ptr;
}
@@ -810,17 +847,17 @@ void *__gem_mmap__cpu(int fd, uint32_t handle, uint64_t offset, uint64_t size, u
{
struct drm_i915_gem_mmap mmap_arg;
- memset(&mmap_arg, 0, sizeof(mmap_arg));
- mmap_arg.handle = handle;
- mmap_arg.offset = offset;
- mmap_arg.size = size;
- if (igt_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &mmap_arg))
- return NULL;
+ memset(&mmap_arg, 0, sizeof(mmap_arg));
+ mmap_arg.handle = handle;
+ mmap_arg.offset = offset;
+ mmap_arg.size = size;
+ if (igt_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &mmap_arg))
+ return NULL;
- VG(VALGRIND_MAKE_MEM_DEFINED(from_user_pointer(mmap_arg.addr_ptr), mmap_arg.size));
+ VG(VALGRIND_MAKE_MEM_DEFINED(from_user_pointer(mmap_arg.addr_ptr), mmap_arg.size));
- errno = 0;
- return from_user_pointer(mmap_arg.addr_ptr);
+ errno = 0;
+ return from_user_pointer(mmap_arg.addr_ptr);
}
/**
@@ -831,13 +868,14 @@ void *__gem_mmap__cpu(int fd, uint32_t handle, uint64_t offset, uint64_t size, u
* @size: size of the mmap arena
* @prot: memory protection bits as used by mmap()
*
- * Like __gem_mmap__cpu() except we assert on failure.
+ * This functions wraps up procedure to establish a memory mapping through
+ * direct cpu access, bypassing the gpu completely and we assert on failure.
*
* Returns: A pointer to the created memory mapping
*/
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 = __gem_mmap(fd, handle, offset, size, prot, false);
igt_assert(ptr);
return ptr;
}
diff --git a/lib/ioctl_wrappers.h b/lib/ioctl_wrappers.h
index b22b36b0..51e66c08 100644
--- a/lib/ioctl_wrappers.h
+++ b/lib/ioctl_wrappers.h
@@ -97,6 +97,7 @@ void *gem_mmap__wc(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsi
void *__gem_mmap__gtt(int fd, uint32_t handle, uint64_t size, unsigned prot);
void *__gem_mmap__cpu(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot);
void *__gem_mmap__wc(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot);
+void *__gem_mmap(int fd, uint32_t handle, uint64_t offset, uint64_t size, unsigned prot, bool wc);
int gem_munmap(void *ptr, uint64_t size);
--
2.17.2
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