Document copyin_nofault, copyout_nofault, uiomove_nofault.

Submitted by:	alc

1 files changed, 42 insertions, 14 deletions

diff --git a/share/man/man9/copy.9 b/share/man/man9/copy.9
index b6b975f82840..37c7a0c47d9a 100644
--- a/share/man/man9/copy.9
+++ b/share/man/man9/copy.9
@@ -34,13 +34,15 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd January 7, 1996
+.Dd July 9, 2011
 .Dt COPY 9
 .Os
 .Sh NAME
 .Nm copy ,
 .Nm copyin ,
+.Nm copyin_nofault ,
 .Nm copyout ,
+.Nm copyout_nofault ,
 .Nm copystr ,
 .Nm copyinstr
 .Nd kernel copy functions
@@ -50,8 +52,12 @@
 .Ft int
 .Fn copyin "const void *uaddr" "void *kaddr" "size_t len"
 .Ft int
+.Fn copyin_nofault "const void *uaddr" "void *kaddr" "size_t len"
+.Ft int
 .Fn copyout "const void *kaddr" "void *uaddr" "size_t len"
 .Ft int
+.Fn copyout_nofault "const void *kaddr" "void *uaddr" "size_t len"
+.Ft int
 .Fn copystr "const void *kfaddr" "void *kdaddr" "size_t len" "size_t *done"
 .Ft int
 .Fn copyinstr "const void *uaddr" "void *kaddr" "size_t len" "size_t *done"
@@ -67,25 +73,40 @@ All but
 copy data from user-space to kernel-space or vice-versa.
 .Pp
 The
-.Nm
-routines provide the following functionality:
-.Bl -tag -width "copyoutstr()"
-.It Fn copyin
-Copies
+.Fn copyin
+and
+.Fn copyin_nofault
+functions copy
 .Fa len
 bytes of data from the user-space address
 .Fa uaddr
 to the kernel-space address
 .Fa kaddr .
-.It Fn copyout
-Copies
+.Pp
+The
+.Fn copyout
+and
+.Fn copyout_nofault
+functions copy
 .Fa len
 bytes of data from the kernel-space address
 .Fa kaddr
 to the user-space address
 .Fa uaddr .
-.It Fn copystr
-Copies a NUL-terminated string, at most
+.Pp
+The
+.Fn copyin_nofault
+and
+.Fn copyout_nofault
+functions require that the kernel-space and user-space data be
+accessible without incurring a page fault.
+The source and destination addresses must be physically mapped for
+read and write access, respectively, and neither the source nor
+destination addresses may be pageable.
+.Pp
+The
+.Fn copystr
+function copies a NUL-terminated string, at most
 .Fa len
 bytes long, from kernel-space address
 .Fa kfaddr
@@ -98,8 +119,10 @@ NUL, is returned in
 .Fa done
 is
 .No non- Ns Dv NULL ) .
-.It Fn copyinstr
-Copies a NUL-terminated string, at most
+.Pp
+The
+.Fn copyinstr
+function copies a NUL-terminated string, at most
 .Fa len
 bytes long, from user-space address
 .Fa uaddr
@@ -121,7 +144,6 @@ is
 .\" The number of bytes actually copied, including the terminating
 .\" NUL, is returned in
 .\" .Fa *done .
-.El
 .Sh RETURN VALUES
 The
 .Nm
@@ -129,7 +151,13 @@ functions return 0 on success or
 .Er EFAULT
 if a bad address is encountered.
 In addition, the
-.Fn copystr ,
+.Fn copyin_nofault
+and
+.Fn copyout_nofault
+functions return
+.Er EFAULT
+if a page fault occurs, and the
+.Fn copystr
 and
 .Fn copyinstr
 .\" .Fn copyinstr ,