tail head cat sleep
QR code linking to this page

Manual Pages  — VM_MAP_STACK

NAME

vm_map_stack, vm_map_growstack – manage process stacks

CONTENTS

SYNOPSIS

#include <sys/param.h>
#include <vm/vm.h>
#include <vm/vm_map.h>

int
vm_map_stack(vm_map_t map, vm_offset_t addrbos, vm_size_t max_ssize, vm_prot_t prot, vm_prot_t max, int cow);

int
vm_map_growstack(struct proc *p, vm_offset_t addr);

DESCRIPTION

The vm_map_stack() function maps a process stack for a new process image. The stack is mapped addrbos in map, with a maximum size of max_ssize. Copy-on-write flags passed in cow are also applied to the new mapping. Protection bits are supplied by prot and max.

It is typically called by execve(2).

The vm_map_growstack() function is responsible for growing a stack for the process p to the desired address addr, similar to the legacy sbrk(2) call.

IMPLEMENTATION NOTES

The vm_map_stack() function calls vm_map_insert(9) to create its mappings.

The vm_map_stack() and vm_map_growstack() functions acquire the process lock on p for the duration of the call.

RETURN VALUES

The vm_map_stack() function returns KERN_SUCCESS if the mapping was allocated successfully.

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 max_ssize could not be accommodated within the current mapping, KERN_NO_SPACE is returned.

Other possible return values for this function are documented in vm_map_insert(9).

The vm_map_growstack() function returns KERN_SUCCESS if addr is already mapped, or if the stack was grown successfully.

It also returns KERN_SUCCESS if addr is outside the stack range; this is done in order to preserve compatibility with the deprecated grow() function previously located in the file vm_machdep.c.

SEE ALSO

vm_map(9), vm_map_insert(9)

AUTHORS

This manual page was written by Bruce M Simpson <Mt bms@spc.org>.

VM_MAP_STACK (9) January 11, 2013

tail head cat sleep
QR code linking to this page


Please direct any comments about this manual page service to Ben Bullock. Privacy policy.

There are two major products of Berkeley, CA -- LSD and UNIX. We don't believe this to be strictly by coincidence.
Jeremy S. Anderson