libsync: add new Sync kernel API

#define SYNC_IOC_LEGACY_FENCE_INFO	_IOWR(SYNC_IOC_MAGIC, 2,\

	struct sync_fence_info_data)

struct sync_merge_data {

 char name[32];

 int32_t fd2;

 int32_t fence;

 uint32_t flags;

 uint32_t pad;

};

struct sync_file_info {

 char name[32];

 int32_t status;

 uint32_t flags;

 uint32_t num_fences;

 uint32_t pad;

 uint64_t sync_fence_info;

};

struct sync_fence_info {

 char obj_name[32];

 char driver_name[32];

 int32_t status;

 uint32_t flags;

 uint64_t timestamp_ns;

};

/**

 * Mainline API:

 *

 * Opcodes  0, 1 and 2 were burned during a API change to avoid users of the

 * old API to get weird errors when trying to handling sync_files. The API

 * change happened during the de-stage of the Sync Framework when there was

 * no upstream users available.

 */

/**

 * DOC: SYNC_IOC_MERGE - merge two fences

 *

 * Takes a struct sync_merge_data.  Creates a new fence containing copies of

 * the sync_pts in both the calling fd and sync_merge_data.fd2.  Returns the

 * new fence's fd in sync_merge_data.fence

 *

 * This is the new version of the Sync API after the de-stage that happened

 * on Linux kernel 4.7.

 */

#define SYNC_IOC_MERGE		_IOWR(SYNC_IOC_MAGIC, 3, struct sync_merge_data)

/**

 * DOC: SYNC_IOC_FILE_INFO - get detailed information on a sync_file

 *

 * Takes a struct sync_file_info. If num_fences is 0, the field is updated

 * with the actual number of fences. If num_fences is > 0, the system will

 * use the pointer provided on sync_fence_info to return up to num_fences of

 * struct sync_fence_info, with detailed fence information.

 *

 * This is the new version of the Sync API after the de-stage that happened

 * on Linux kernel 4.7.

 */

#define SYNC_IOC_FILE_INFO	_IOWR(SYNC_IOC_MAGIC, 4, struct sync_file_info)

/* timeout in msecs */

int sync_wait(int fd, int timeout);

int sync_merge(const char *name, int fd1, int fd2);