MFC r313018:

Add kern_pread() and kern_pwrite(), and use it in compats instead
of their sys_*() counterparts. The svr4 is left unchanged.

Sponsored by:	DARPA, AFRL

4 files changed, 48 insertions, 77 deletions

diff --git a/sys/compat/freebsd32/freebsd32_misc.c b/sys/compat/freebsd32/freebsd32_misc.c
index 7c354c8..8857e91 100644
--- a/sys/compat/freebsd32/freebsd32_misc.c
+++ b/sys/compat/freebsd32/freebsd32_misc.c
@@ -1442,25 +1442,17 @@ freebsd4_freebsd32_fhstatfs(struct thread *td, struct freebsd4_freebsd32_fhstatf
 int
 freebsd32_pread(struct thread *td, struct freebsd32_pread_args *uap)
 {
-	struct pread_args ap;
 
-	ap.fd = uap->fd;
-	ap.buf = uap->buf;
-	ap.nbyte = uap->nbyte;
-	ap.offset = PAIR32TO64(off_t,uap->offset);
-	return (sys_pread(td, &ap));
+	return (kern_pread(td, uap->fd, uap->buf, uap->nbyte,
+	    PAIR32TO64(off_t, uap->offset)));
 }
 
 int
 freebsd32_pwrite(struct thread *td, struct freebsd32_pwrite_args *uap)
 {
-	struct pwrite_args ap;
 
-	ap.fd = uap->fd;
-	ap.buf = uap->buf;
-	ap.nbyte = uap->nbyte;
-	ap.offset = PAIR32TO64(off_t,uap->offset);
-	return (sys_pwrite(td, &ap));
+	return (kern_pwrite(td, uap->fd, uap->buf, uap->nbyte,
+	    PAIR32TO64(off_t, uap->offset)));
 }
 
 #ifdef COMPAT_43
@@ -1549,25 +1541,17 @@ freebsd32_getdirentries(struct thread *td,
 int
 freebsd6_freebsd32_pread(struct thread *td, struct freebsd6_freebsd32_pread_args *uap)
 {
-	struct pread_args ap;
 
-	ap.fd = uap->fd;
-	ap.buf = uap->buf;
-	ap.nbyte = uap->nbyte;
-	ap.offset = PAIR32TO64(off_t,uap->offset);
-	return (sys_pread(td, &ap));
+	return (kern_pread(td, uap->fd, uap->buf, uap->nbyte,
+	    PAIR32TO64(off_t, uap->offset)));
 }
 
 int
 freebsd6_freebsd32_pwrite(struct thread *td, struct freebsd6_freebsd32_pwrite_args *uap)
 {
-	struct pwrite_args ap;
 
-	ap.fd = uap->fd;
-	ap.buf = uap->buf;
-	ap.nbyte = uap->nbyte;
-	ap.offset = PAIR32TO64(off_t,uap->offset);
-	return (sys_pwrite(td, &ap));
+	return (kern_pwrite(td, uap->fd, uap->buf, uap->nbyte,
+	    PAIR32TO64(off_t, uap->offset)));
 }
 
 int
diff --git a/sys/compat/linux/linux_file.c b/sys/compat/linux/linux_file.c
index b549274..37b8595 100644
--- a/sys/compat/linux/linux_file.c
+++ b/sys/compat/linux/linux_file.c
@@ -998,20 +998,13 @@ linux_fdatasync(td, uap)
 }
 
 int
-linux_pread(td, uap)
-	struct thread *td;
-	struct linux_pread_args *uap;
+linux_pread(struct thread *td, struct linux_pread_args *uap)
 {
-	struct pread_args bsd;
 	cap_rights_t rights;
 	struct vnode *vp;
 	int error;
 
-	bsd.fd = uap->fd;
-	bsd.buf = uap->buf;
-	bsd.nbyte = uap->nbyte;
-	bsd.offset = uap->offset;
-	error = sys_pread(td, &bsd);
+	error = kern_pread(td, uap->fd, uap->buf, uap->nbyte, uap->offset);
 	if (error == 0) {
 		/* This seems to violate POSIX but linux does it */
 		error = fgetvp(td, uap->fd,
@@ -1028,17 +1021,10 @@ linux_pread(td, uap)
 }
 
 int
-linux_pwrite(td, uap)
-	struct thread *td;
-	struct linux_pwrite_args *uap;
+linux_pwrite(struct thread *td, struct linux_pwrite_args *uap)
 {
-	struct pwrite_args bsd;
 
-	bsd.fd = uap->fd;
-	bsd.buf = uap->buf;
-	bsd.nbyte = uap->nbyte;
-	bsd.offset = uap->offset;
-	return (sys_pwrite(td, &bsd));
+	return (kern_pwrite(td, uap->fd, uap->buf, uap->nbyte, uap->offset));
 }
 
 int
diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c
index ab875a1..acf05d1 100644
--- a/sys/kern/sys_generic.c
+++ b/sys/kern/sys_generic.c
@@ -220,39 +220,37 @@ struct pread_args {
 };
 #endif
 int
-sys_pread(td, uap)
-	struct thread *td;
-	struct pread_args *uap;
+sys_pread(struct thread *td, struct pread_args *uap)
+{
+
+	return (kern_pread(td, uap->fd, uap->buf, uap->nbyte, uap->offset));
+}
+
+int
+kern_pread(struct thread *td, int fd, void *buf, size_t nbyte, off_t offset)
 {
 	struct uio auio;
 	struct iovec aiov;
 	int error;
 
-	if (uap->nbyte > IOSIZE_MAX)
+	if (nbyte > IOSIZE_MAX)
 		return (EINVAL);
-	aiov.iov_base = uap->buf;
-	aiov.iov_len = uap->nbyte;
+	aiov.iov_base = buf;
+	aiov.iov_len = nbyte;
 	auio.uio_iov = &aiov;
 	auio.uio_iovcnt = 1;
-	auio.uio_resid = uap->nbyte;
+	auio.uio_resid = nbyte;
 	auio.uio_segflg = UIO_USERSPACE;
-	error = kern_preadv(td, uap->fd, &auio, uap->offset);
-	return(error);
+	error = kern_preadv(td, fd, &auio, offset);
+	return (error);
 }
 
 #if defined(COMPAT_FREEBSD6)
 int
-freebsd6_pread(td, uap)
-	struct thread *td;
-	struct freebsd6_pread_args *uap;
+freebsd6_pread(struct thread *td, struct freebsd6_pread_args *uap)
 {
-	struct pread_args oargs;
 
-	oargs.fd = uap->fd;
-	oargs.buf = uap->buf;
-	oargs.nbyte = uap->nbyte;
-	oargs.offset = uap->offset;
-	return (sys_pread(td, &oargs));
+	return (kern_pread(td, uap->fd, uap->buf, uap->nbyte, uap->offset));
 }
 #endif
 
@@ -436,39 +434,38 @@ struct pwrite_args {
 };
 #endif
 int
-sys_pwrite(td, uap)
-	struct thread *td;
-	struct pwrite_args *uap;
+sys_pwrite(struct thread *td, struct pwrite_args *uap)
+{
+
+	return (kern_pwrite(td, uap->fd, uap->buf, uap->nbyte, uap->offset));
+}
+
+int
+kern_pwrite(struct thread *td, int fd, const void *buf, size_t nbyte,
+    off_t offset)
 {
 	struct uio auio;
 	struct iovec aiov;
 	int error;
 
-	if (uap->nbyte > IOSIZE_MAX)
+	if (nbyte > IOSIZE_MAX)
 		return (EINVAL);
-	aiov.iov_base = (void *)(uintptr_t)uap->buf;
-	aiov.iov_len = uap->nbyte;
+	aiov.iov_base = (void *)(uintptr_t)buf;
+	aiov.iov_len = nbyte;
 	auio.uio_iov = &aiov;
 	auio.uio_iovcnt = 1;
-	auio.uio_resid = uap->nbyte;
+	auio.uio_resid = nbyte;
 	auio.uio_segflg = UIO_USERSPACE;
-	error = kern_pwritev(td, uap->fd, &auio, uap->offset);
+	error = kern_pwritev(td, fd, &auio, offset);
 	return(error);
 }
 
 #if defined(COMPAT_FREEBSD6)
 int
-freebsd6_pwrite(td, uap)
-	struct thread *td;
-	struct freebsd6_pwrite_args *uap;
+freebsd6_pwrite(struct thread *td, struct freebsd6_pwrite_args *uap)
 {
-	struct pwrite_args oargs;
 
-	oargs.fd = uap->fd;
-	oargs.buf = uap->buf;
-	oargs.nbyte = uap->nbyte;
-	oargs.offset = uap->offset;
-	return (sys_pwrite(td, &oargs));
+	return (kern_pwrite(td, uap->fd, uap->buf, uap->nbyte, uap->offset));
 }
 #endif
 
diff --git a/sys/sys/syscallsubr.h b/sys/sys/syscallsubr.h
index d938563..f9cb3ed 100644
--- a/sys/sys/syscallsubr.h
+++ b/sys/sys/syscallsubr.h
@@ -177,11 +177,15 @@ int	kern_posix_fallocate(struct thread *td, int fd, off_t offset,
 	    off_t len);
 int	kern_procctl(struct thread *td, enum idtype idtype, id_t id, int com,
 	    void *data);
+int	kern_pread(struct thread *td, int fd, void *buf, size_t nbyte,
+	    off_t offset);
 int	kern_preadv(struct thread *td, int fd, struct uio *auio, off_t offset);
 int	kern_pselect(struct thread *td, int nd, fd_set *in, fd_set *ou,
 	    fd_set *ex, struct timeval *tvp, sigset_t *uset, int abi_nfdbits);
 int	kern_ptrace(struct thread *td, int req, pid_t pid, void *addr,
 	    int data);
+int	kern_pwrite(struct thread *td, int fd, const void *buf, size_t nbyte,
+	    off_t offset);
 int	kern_pwritev(struct thread *td, int fd, struct uio *auio, off_t offset);
 int	kern_readlinkat(struct thread *td, int fd, char *path,
 	    enum uio_seg pathseg, char *buf, enum uio_seg bufseg, size_t count);