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diff --git a/share/man/man9/Makefile b/share/man/man9/Makefile
--- a/share/man/man9/Makefile
+++ b/share/man/man9/Makefile
@@ -2325,6 +2325,7 @@
uidinfo.9 uihold.9
MLINKS+=uio.9 uiomove.9 \
uio.9 uiomove_frombuf.9 \
+ uio.9 uiomove_fromphys.9 \
uio.9 uiomove_nofault.9
MLINKS+=unr.9 alloc_unr.9 \
unr.9 alloc_unrl.9 \
diff --git a/share/man/man9/uio.9 b/share/man/man9/uio.9
--- a/share/man/man9/uio.9
+++ b/share/man/man9/uio.9
@@ -30,6 +30,7 @@
.Nm uio ,
.Nm uiomove ,
.Nm uiomove_frombuf ,
+.Nm uiomove_fromphys ,
.Nm uiomove_nofault
.Nd device driver I/O routines
.Sh SYNOPSIS
@@ -37,25 +38,29 @@
.In sys/uio.h
.Bd -literal
struct uio {
- struct iovec *uio_iov; /* scatter/gather list */
- int uio_iovcnt; /* length of scatter/gather list */
- off_t uio_offset; /* offset in target object */
- ssize_t uio_resid; /* remaining bytes to copy */
- enum uio_seg uio_segflg; /* address space */
- enum uio_rw uio_rw; /* operation */
- struct thread *uio_td; /* owner */
+ struct iovec *uio_iov; /* scatter/gather list */
+ int uio_iovcnt; /* length of scatter/gather list */
+ off_t uio_offset; /* offset in target object */
+ ssize_t uio_resid; /* remaining bytes to process */
+ enum uio_seg uio_segflg; /* address space */
+ enum uio_rw uio_rw; /* operation */
+ struct thread *uio_td; /* owner */
};
.Ed
+.Pp
.Ft int
.Fn uiomove "void *buf" "int howmuch" "struct uio *uiop"
.Ft int
.Fn uiomove_frombuf "void *buf" "int howmuch" "struct uio *uiop"
.Ft int
+.Fn uiomove_fromphys "vm_page_t ma[]" "vm_offset_t offset" "int howmuch" "struct uio *uiop"
+.Ft int
.Fn uiomove_nofault "void *buf" "int howmuch" "struct uio *uiop"
.Sh DESCRIPTION
The functions
.Fn uiomove ,
.Fn uiomove_frombuf ,
+.Fn uiomove_fromphys ,
and
.Fn uiomove_nofault
are used to transfer data between buffers and I/O vectors that might
@@ -152,10 +157,30 @@
.Va uio_offset
is greater than or equal to the buffer size, the result is success
with no bytes transferred, effectively signaling EOF.
+.Pp
+The
+.Fn uiomove_fromphys
+function implements
+.Fn uiomove
+from physical memory using the direct map to avoid the creation and destruction
+of ephemeral memory mappings.
+The physical pages to be used in the transfer is described by the
+.Fa "ma[]"
+array.
+The
+.Fa "offset"
+argument is the page offset of the first page in the
+.Fa "ma[]"
+array.
+.Sh IMPLEMENTATION NOTES
+The implementation of
+.Fn uiomove_fromphys
+is machine dependent.
.Sh RETURN VALUES
On success
.Fn uiomove ,
.Fn uiomove_frombuf ,
+.Fn uiomove_fromphys ,
and
.Fn uiomove_nofault
will return 0; on error they will return an appropriate error code.
@@ -168,7 +193,7 @@
partial read), it is just here to demonstrate the
.Nm
handling.
-.Bd -literal
+.Bd -literal -offset 2n
/* MIN() can be found there: */
#include <sys/param.h>
@@ -200,7 +225,8 @@
}
.Ed
.Sh ERRORS
-.Fn uiomove
+.Fn uiomove ,
+.Fn uiomove_fromphys
and
.Fn uiomove_nofault
will fail and return the following error code if:
@@ -211,7 +237,7 @@
or
.Xr copyout 9
returned
-.Er EFAULT
+.Er EFAULT .
.El
.Pp
In addition,

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