1.\" 2.\" Copyright (c) 2015 Mark Johnston <markj@FreeBSD.org> 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 14.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 17.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 18.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 19.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 20.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 22.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23.\" 24.Dd December 7, 2015 25.Dt PROC_RWMEM 9 26.Os 27.Sh NAME 28.Nm proc_rwmem , 29.Nm proc_readmem , 30.Nm proc_writemem 31.Nd read from or write to a process address space 32.Sh SYNOPSIS 33.In sys/types.h 34.In sys/ptrace.h 35.Ft int 36.Fn proc_rwmem "struct proc *p" "struct uio *uio" 37.Ft ssize_t 38.Fn proc_readmem "struct thread *td" "struct proc *p" "vm_offset_t va" "void *buf" "size_t len" 39.Ft ssize_t 40.Fn proc_writemem "struct thread *td" "struct proc *p" "vm_offset_t va" "void *buf" "size_t len" 41.Sh DESCRIPTION 42These functions are used to read to or write from the address space of the 43process 44.Fa p . 45The 46.Fn proc_rwmem 47function requires the caller to specify the I/O parameters using a 48.Vt "struct uio" , 49described in 50.Xr uio 9 . 51The 52.Fn proc_readmem 53and 54.Fn proc_writemem 55functions provide a simpler, less general interface which allows the caller to 56read into or write the kernel buffer 57.Fa buf 58of size 59.Fa len 60from or to the memory at offset 61.Fa va 62in the address space of 63.Fa p . 64The operation is performed on behalf of thread 65.Fa td , 66which will most often be the current thread. 67.Pp 68These functions may sleep and thus may not be called with any non-sleepable 69locks held. 70The process 71.Fa p 72must be held by the caller using 73.Xr PHOLD 9 . 74.Sh RETURN VALUES 75The 76.Fn proc_rwmem 77function returns 78.Dv 0 79on success. 80.Dv EFAULT 81is returned if the specified user address is invalid, and 82.Dv ENOMEM 83is returned if the target pages could not be faulted in due to a resource 84shortage. 85.Pp 86The 87.Fn proc_readmem 88and 89.Fn proc_writemem 90functions return the number of bytes read or written, respectively. 91This may be smaller than the number of bytes requested, for example if the 92request spans multiple pages in the process address space and one of them after 93the first is not mapped. 94Otherwise, -1 is returned. 95.Sh SEE ALSO 96.Xr copyin 9 , 97.Xr locking 9 , 98.Xr PHOLD 9 , 99.Xr uio 9 100.Sh AUTHORS 101This manual page was written by 102.An Mark Johnston Aq Mt markj@FreeBSD.org . 103