Copyright (c) 2003 Bruce M Simpson <bms@spc.org>
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
$FreeBSD: head/share/man/man9/vm_map_stack.9 245268 2013-01-10 22:36:30Z pluknet $
.Dd January 11, 2013 .Dt VM_MAP_STACK 9 .Os .Sh NAME .Nm vm_map_stack , .Nm vm_map_growstack .Nd manage process stacks .Sh SYNOPSIS n sys/param.h n vm/vm.h n vm/vm_map.h .Ft int .Fo vm_map_stack .Fa "vm_map_t map" "vm_offset_t addrbos" "vm_size_t max_ssize" "vm_prot_t prot" .Fa "vm_prot_t max" "int cow" .Fc .Ft int .Fn vm_map_growstack "struct proc *p" "vm_offset_t addr" .Sh DESCRIPTION The .Fn vm_map_stack function maps a process stack for a new process image. The stack is mapped .Fa addrbos in .Fa map , with a maximum size of .Fa max_ssize . Copy-on-write flags passed in .Fa cow are also applied to the new mapping. Protection bits are supplied by .Fa prot and .Fa max .
p It is typically called by .Xr execve 2 .
p The .Fn vm_map_growstack function is responsible for growing a stack for the process .Fa p to the desired address .Fa addr , similar to the legacy .Xr sbrk 2 call. .Sh IMPLEMENTATION NOTES The .Fn vm_map_stack function calls .Xr vm_map_insert 9 to create its mappings.
p The .Fn vm_map_stack and .Fn vm_map_growstack functions acquire the process lock on .Fa p for the duration of the call. .Sh RETURN VALUES The .Fn vm_map_stack function returns .Dv KERN_SUCCESS if the mapping was allocated successfully.
p Otherwise, if mapping the stack would exceed the process's VMEM resource limit, or if the specified bottom-of-stack address is out of range for the map, or if there is already a mapping at the address which would result, or if .Fa max_ssize could not be accommodated within the current mapping, .Dv KERN_NO_SPACE is returned.
p Other possible return values for this function are documented in .Xr vm_map_insert 9 .
p The .Fn vm_map_growstack function returns .Dv KERN_SUCCESS if .Fa addr is already mapped, or if the stack was grown successfully.
p It also returns .Dv KERN_SUCCESS if .Fa addr is outside the stack range; this is done in order to preserve compatibility with the deprecated .Fn grow function previously located in the file
a vm_machdep.c . .Sh SEE ALSO .Xr vm_map 9 , .Xr vm_map_insert 9 .Sh AUTHORS This manual page was written by .An Bruce M Simpson Aq bms@spc.org .