Merge tag 'for-5.3/io_uring-20190711' of git://git.kernel.dk/linux-block

Pull io_uring updates from Jens Axboe:
 "This contains:

   - Support for recvmsg/sendmsg as first class opcodes.

     I don't envision going much further down this path, as there are
     plans in progress to support potentially any system call in an
     async fashion through io_uring. But I think it does make sense to
     have certain core ops available directly, especially those that can
     support a "try this non-blocking" flag/mode. (me)

   - Handle generic short reads automatically.

     This can happen fairly easily if parts of the buffered read is
     cached. Since the application needs to issue another request for
     the remainder, just do this internally and save kernel/user
     roundtrip while providing a nicer more robust API. (me)

   - Support for linked SQEs.

     This allows SQEs to depend on each other, enabling an application
     to eg queue a read-from-this-file,write-to-that-file pair. (me)

   - Fix race in stopping SQ thread (Jackie)"

* tag 'for-5.3/io_uring-20190711' of git://git.kernel.dk/linux-block:
  io_uring: fix io_sq_thread_stop running in front of io_sq_thread
  io_uring: add support for recvmsg()
  io_uring: add support for sendmsg()
  io_uring: add support for sqe links
  io_uring: punt short reads to async context
  uio: make import_iovec()/compat_import_iovec() return bytes on success

3 files changed, 13 insertions, 2 deletions

diff --git a/include/linux/socket.h b/include/linux/socket.h
index b57cd8bf96e2..97523818cb14 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -12,6 +12,7 @@
 
 struct pid;
 struct cred;
+struct socket;
 
 #define __sockaddr_check_size(size)	\
 	BUILD_BUG_ON(((size) > sizeof(struct __kernel_sockaddr_storage)))
@@ -374,6 +375,12 @@ extern int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg,
 extern int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg,
 			  unsigned int vlen, unsigned int flags,
 			  bool forbid_cmsg_compat);
+extern long __sys_sendmsg_sock(struct socket *sock,
+			       struct user_msghdr __user *msg,
+			       unsigned int flags);
+extern long __sys_recvmsg_sock(struct socket *sock,
+			       struct user_msghdr __user *msg,
+			       unsigned int flags);
 
 /* helpers which do the actual work for syscalls */
 extern int __sys_recvfrom(int fd, void __user *ubuf, size_t size,
diff --git a/include/linux/uio.h b/include/linux/uio.h
index cea1761c5672..ab5f523bc0df 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -267,13 +267,13 @@ bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum, struct
 size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp,
 		struct iov_iter *i);
 
-int import_iovec(int type, const struct iovec __user * uvector,
+ssize_t import_iovec(int type, const struct iovec __user * uvector,
 		 unsigned nr_segs, unsigned fast_segs,
 		 struct iovec **iov, struct iov_iter *i);
 
 #ifdef CONFIG_COMPAT
 struct compat_iovec;
-int compat_import_iovec(int type, const struct compat_iovec __user * uvector,
+ssize_t compat_import_iovec(int type, const struct compat_iovec __user * uvector,
 		 unsigned nr_segs, unsigned fast_segs,
 		 struct iovec **iov, struct iov_iter *i);
 #endif
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index a0c460025036..1e1652f25cc1 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -27,6 +27,7 @@ struct io_uring_sqe {
 		__u32		fsync_flags;
 		__u16		poll_events;
 		__u32		sync_range_flags;
+		__u32		msg_flags;
 	};
 	__u64	user_data;	/* data to be passed back at completion time */
 	union {
@@ -40,6 +41,7 @@ struct io_uring_sqe {
  */
 #define IOSQE_FIXED_FILE	(1U << 0)	/* use fixed fileset */
 #define IOSQE_IO_DRAIN		(1U << 1)	/* issue after inflight IO */
+#define IOSQE_IO_LINK		(1U << 2)	/* links next sqe */
 
 /*
  * io_uring_setup() flags
@@ -57,6 +59,8 @@ struct io_uring_sqe {
 #define IORING_OP_POLL_ADD	6
 #define IORING_OP_POLL_REMOVE	7
 #define IORING_OP_SYNC_FILE_RANGE	8
+#define IORING_OP_SENDMSG	9
+#define IORING_OP_RECVMSG	10
 
 /*
  * sqe->fsync_flags