path: root/arch/xtensa
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authorEric B Munson <emunson@akamai.com>2015-11-05 18:51:39 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-05 19:34:48 -0800
commitb0f205c2a3082dd9081f9a94e50658c5fa906ff1 (patch)
treec2de47f26d57919ed73e8930f251d46ac0f4dc7a /arch/xtensa
parentde60f5f10c58d4f34b68622442c0e04180367f3f (diff)
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>
Diffstat (limited to 'arch/xtensa')
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h
index 201aec0e0446..360944e1da52 100644
--- a/arch/xtensa/include/uapi/asm/mman.h
+++ b/arch/xtensa/include/uapi/asm/mman.h
@@ -74,6 +74,12 @@
#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 */