linux/arch/mips/include/uapi/asm/mman.h
Eric B Munson b0f205c2a3 mm: mlock: add mlock flags to enable VM_LOCKONFAULT usage
The previous patch introduced a flag that specified pages in a VMA should
be placed on the unevictable LRU, but they should not be made present when
the area is created.  This patch adds the ability to set this state via
the new mlock system calls.

We add MLOCK_ONFAULT for mlock2 and MCL_ONFAULT for mlockall.
MLOCK_ONFAULT will set the VM_LOCKONFAULT modifier for VM_LOCKED.
MCL_ONFAULT should be used as a modifier to the two other mlockall flags.
When used with MCL_CURRENT, all current mappings will be marked with
VM_LOCKED | VM_LOCKONFAULT.  When used with MCL_FUTURE, the mm->def_flags
will be marked with VM_LOCKED | VM_LOCKONFAULT.  When used with both
MCL_CURRENT and MCL_FUTURE, all current mappings and mm->def_flags will be
marked with VM_LOCKED | VM_LOCKONFAULT.

Prior to this patch, mlockall() will unconditionally clear the
mm->def_flags any time it is called without MCL_FUTURE.  This behavior is
maintained after adding MCL_ONFAULT.  If a call to mlockall(MCL_FUTURE) is
followed by mlockall(MCL_CURRENT), the mm->def_flags will be cleared and
new VMAs will be unlocked.  This remains true with or without MCL_ONFAULT
in either mlockall() invocation.

munlock() will unconditionally clear both vma flags.  munlockall()
unconditionally clears for VMA flags on all VMAs and in the mm->def_flags
field.

Signed-off-by: Eric B Munson <emunson@akamai.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00

108 lines
4.1 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1995, 1999, 2002 by Ralf Baechle
*/
#ifndef _ASM_MMAN_H
#define _ASM_MMAN_H
/*
* Protections are chosen from these bits, OR'd together. The
* implementation does not necessarily support PROT_EXEC or PROT_WRITE
* without PROT_READ. The only guarantees are that no writing will be
* allowed without PROT_WRITE and no access will be allowed for PROT_NONE.
*/
#define PROT_NONE 0x00 /* page can not be accessed */
#define PROT_READ 0x01 /* page can be read */
#define PROT_WRITE 0x02 /* page can be written */
#define PROT_EXEC 0x04 /* page can be executed */
/* 0x08 reserved for PROT_EXEC_NOFLUSH */
#define PROT_SEM 0x10 /* page may be used for atomic ops */
#define PROT_GROWSDOWN 0x01000000 /* mprotect flag: extend change to start of growsdown vma */
#define PROT_GROWSUP 0x02000000 /* mprotect flag: extend change to end of growsup vma */
/*
* Flags for mmap
*/
#define MAP_SHARED 0x001 /* Share changes */
#define MAP_PRIVATE 0x002 /* Changes are private */
#define MAP_TYPE 0x00f /* Mask for type of mapping */
#define MAP_FIXED 0x010 /* Interpret addr exactly */
/* not used by linux, but here to make sure we don't clash with ABI defines */
#define MAP_RENAME 0x020 /* Assign page to file */
#define MAP_AUTOGROW 0x040 /* File may grow by writing */
#define MAP_LOCAL 0x080 /* Copy on fork/sproc */
#define MAP_AUTORSRV 0x100 /* Logical swap reserved on demand */
/* These are linux-specific */
#define MAP_NORESERVE 0x0400 /* don't check for reservations */
#define MAP_ANONYMOUS 0x0800 /* don't use a file */
#define MAP_GROWSDOWN 0x1000 /* stack-like segment */
#define MAP_DENYWRITE 0x2000 /* ETXTBSY */
#define MAP_EXECUTABLE 0x4000 /* mark it as an executable */
#define MAP_LOCKED 0x8000 /* pages are locked */
#define MAP_POPULATE 0x10000 /* populate (prefault) pagetables */
#define MAP_NONBLOCK 0x20000 /* do not block on IO */
#define MAP_STACK 0x40000 /* give out an address that is best suited for process/thread stacks */
#define MAP_HUGETLB 0x80000 /* create a huge page mapping */
/*
* Flags for msync
*/
#define MS_ASYNC 0x0001 /* sync memory asynchronously */
#define MS_INVALIDATE 0x0002 /* invalidate mappings & caches */
#define MS_SYNC 0x0004 /* synchronous memory sync */
/*
* Flags for mlockall
*/
#define MCL_CURRENT 1 /* lock all current mappings */
#define MCL_FUTURE 2 /* lock all future mappings */
#define MCL_ONFAULT 4 /* lock all pages that are faulted in */
/*
* Flags for mlock
*/
#define MLOCK_ONFAULT 0x01 /* Lock pages in range after they are faulted in, do not prefault */
#define MADV_NORMAL 0 /* no further special treatment */
#define MADV_RANDOM 1 /* expect random page references */
#define MADV_SEQUENTIAL 2 /* expect sequential page references */
#define MADV_WILLNEED 3 /* will need these pages */
#define MADV_DONTNEED 4 /* don't need these pages */
/* common parameters: try to keep these consistent across architectures */
#define MADV_REMOVE 9 /* remove these pages & resources */
#define MADV_DONTFORK 10 /* don't inherit across fork */
#define MADV_DOFORK 11 /* do inherit across fork */
#define MADV_MERGEABLE 12 /* KSM may merge identical pages */
#define MADV_UNMERGEABLE 13 /* KSM may not merge identical pages */
#define MADV_HWPOISON 100 /* poison a page for testing */
#define MADV_HUGEPAGE 14 /* Worth backing with hugepages */
#define MADV_NOHUGEPAGE 15 /* Not worth backing with hugepages */
#define MADV_DONTDUMP 16 /* Explicity exclude from the core dump,
overrides the coredump filter bits */
#define MADV_DODUMP 17 /* Clear the MADV_NODUMP flag */
/* compatibility flags */
#define MAP_FILE 0
/*
* When MAP_HUGETLB is set bits [26:31] encode the log2 of the huge page size.
* This gives us 6 bits, which is enough until someone invents 128 bit address
* spaces.
*
* Assume these are all power of twos.
* When 0 use the default page size.
*/
#define MAP_HUGE_SHIFT 26
#define MAP_HUGE_MASK 0x3f
#endif /* _ASM_MMAN_H */