[Why] The kernel has support for creating a blob with flags, particularly write only flag. The user space should use libdrm library to make use of the blob flags.
[How] Create drmModeCreatePropertyBlobWithFlags which has the same implementation as the existing drmModeCreatePropertyBlob but with a flag argument.
Signed-off-by: Mark Yacoub markyacoub@chromium.org --- include/drm/drm_mode.h | 6 ++++++ xf86drmMode.c | 7 +++++++ xf86drmMode.h | 3 +++ 3 files changed, 16 insertions(+)
diff --git a/include/drm/drm_mode.h b/include/drm/drm_mode.h index 9b6722d4..b0df381f 100644 --- a/include/drm/drm_mode.h +++ b/include/drm/drm_mode.h @@ -991,6 +991,9 @@ struct drm_format_modifier { __u64 modifier; };
+#define DRM_MODE_CREATE_BLOB_WRITE_ONLY \ + (1 << 0) /* data of the blob can't be read by user space */ + /** * struct drm_mode_create_blob - Create New blob property * @@ -1004,6 +1007,9 @@ struct drm_mode_create_blob { __u32 length; /** @blob_id: Return: new property ID. */ __u32 blob_id; + /** Flags for special handling. */ + __u32 flags; + __u32 pad; };
/** diff --git a/xf86drmMode.c b/xf86drmMode.c index 87e96603..072b395c 100644 --- a/xf86drmMode.c +++ b/xf86drmMode.c @@ -1592,6 +1592,12 @@ drm_public int drmModeCreatePropertyBlob(int fd, const void *data, size_t length, uint32_t *id) { + return drmModeCreatePropertyBlobWithFlags(fd, data, length, id, 0); +} + +extern int drmModeCreatePropertyBlobWithFlags(int fd, const void *data, + size_t length, uint32_t *id, + uint32_t flags) { struct drm_mode_create_blob create; int ret;
@@ -1603,6 +1609,7 @@ drmModeCreatePropertyBlob(int fd, const void *data, size_t length, create.length = length; create.data = (uintptr_t) data; create.blob_id = 0; + create.flags = flags; *id = 0;
ret = DRM_IOCTL(fd, DRM_IOCTL_MODE_CREATEPROPBLOB, &create); diff --git a/xf86drmMode.h b/xf86drmMode.h index 19bf91dd..f22b8174 100644 --- a/xf86drmMode.h +++ b/xf86drmMode.h @@ -450,6 +450,9 @@ extern int drmModeAtomicCommit(int fd,
extern int drmModeCreatePropertyBlob(int fd, const void *data, size_t size, uint32_t *id); +extern int drmModeCreatePropertyBlobWithFlags(int fd, const void *data, + size_t size, uint32_t *id, + uint32_t flags); extern int drmModeDestroyPropertyBlob(int fd, uint32_t id);
/*