Commit cc2383ec authored by Konstantin Khlebnikov's avatar Konstantin Khlebnikov Committed by Linus Torvalds
Browse files

mm: introduce arch-specific vma flag VM_ARCH_1 



Combine several arch-specific vma flags into one.

before patch:

        0x00000200      0x01000000      0x20000000      0x40000000
x86     VM_NOHUGEPAGE   VM_HUGEPAGE     -               VM_PAT
powerpc -               -               VM_SAO          -
parisc  VM_GROWSUP      -               -               -
ia64    VM_GROWSUP      -               -               -
nommu   -               VM_MAPPED_COPY  -               -
others  -               -               -               -

after patch:

        0x00000200      0x01000000      0x20000000      0x40000000
x86     -               VM_PAT          VM_HUGEPAGE     VM_NOHUGEPAGE
powerpc -               VM_SAO          -               -
parisc  -               VM_GROWSUP      -               -
ia64    -               VM_GROWSUP      -               -
nommu   -               VM_MAPPED_COPY  -               -
others  -               VM_ARCH_1       -               -

And voila! One completely free bit.

Signed-off-by: default avatarKonstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b3b9c293

include/linux/mm.h

+21 −13
Original line number Diff line number Diff line
@@ -70,6 +70,8 @@ extern unsigned int kobjsize(const void *objp); 
/*

 * vm_flags in vm_area_struct, see mm_types.h.

 */

#define VM_NONE		0x00000000



#define VM_READ		0x00000001	/* currently active flags */

#define VM_WRITE	0x00000002

#define VM_EXEC		0x00000004
@@ -82,12 +84,6 @@ extern unsigned int kobjsize(const void *objp); 
#define VM_MAYSHARE	0x00000080



#define VM_GROWSDOWN	0x00000100	/* general info on the segment */

#if defined(CONFIG_STACK_GROWSUP) || defined(CONFIG_IA64)

#define VM_GROWSUP	0x00000200

#else

#define VM_GROWSUP	0x00000000

#define VM_NOHUGEPAGE	0x00000200	/* MADV_NOHUGEPAGE marked this vma */

#endif

#define VM_PFNMAP	0x00000400	/* Page-ranges managed without "struct page", just pure PFN */

#define VM_DENYWRITE	0x00000800	/* ETXTBSY on write attempts.. */
@@ -106,20 +102,32 @@ extern unsigned int kobjsize(const void *objp); 
#define VM_NORESERVE	0x00200000	/* should the VM suppress accounting */

#define VM_HUGETLB	0x00400000	/* Huge TLB Page VM */

#define VM_NONLINEAR	0x00800000	/* Is non-linear (remap_file_pages) */

#ifndef CONFIG_TRANSPARENT_HUGEPAGE

#define VM_MAPPED_COPY	0x01000000	/* T if mapped copy of data (nommu mmap) */

#else

#define VM_HUGEPAGE	0x01000000	/* MADV_HUGEPAGE marked this vma */

#endif

#define VM_ARCH_1	0x01000000	/* Architecture-specific flag */

#define VM_INSERTPAGE	0x02000000	/* The vma has had "vm_insert_page()" done on it */

#define VM_NODUMP	0x04000000	/* Do not include in the core dump */



#define VM_CAN_NONLINEAR 0x08000000	/* Has ->fault & does nonlinear pages */

#define VM_MIXEDMAP	0x10000000	/* Can contain "struct page" and pure PFN pages */

#define VM_SAO		0x20000000	/* Strong Access Ordering (powerpc) */

#define VM_PAT		0x40000000	/* PAT reserves whole VMA at once (x86) */

#define VM_HUGEPAGE	0x20000000	/* MADV_HUGEPAGE marked this vma */

#define VM_NOHUGEPAGE	0x40000000	/* MADV_NOHUGEPAGE marked this vma */

#define VM_MERGEABLE	0x80000000	/* KSM may merge identical pages */



#if defined(CONFIG_X86)

# define VM_PAT		VM_ARCH_1	/* PAT reserves whole VMA at once (x86) */

#elif defined(CONFIG_PPC)

# define VM_SAO		VM_ARCH_1	/* Strong Access Ordering (powerpc) */

#elif defined(CONFIG_PARISC)

# define VM_GROWSUP	VM_ARCH_1

#elif defined(CONFIG_IA64)

# define VM_GROWSUP	VM_ARCH_1

#elif !defined(CONFIG_MMU)

# define VM_MAPPED_COPY	VM_ARCH_1	/* T if mapped copy of data (nommu mmap) */

#endif



#ifndef VM_GROWSUP

# define VM_GROWSUP	VM_NONE

#endif



/* Bits set in the VMA until the stack is in its final location */

#define VM_STACK_INCOMPLETE_SETUP	(VM_RAND_READ | VM_SEQ_READ)

mm/huge_memory.c

+1 −1
Original line number Diff line number Diff line
@@ -1491,7 +1491,7 @@ out: 
	return ret;

}



#define VM_NO_THP (VM_SPECIAL|VM_INSERTPAGE|VM_MIXEDMAP|VM_SAO| \

#define VM_NO_THP (VM_SPECIAL|VM_INSERTPAGE|VM_MIXEDMAP| \

		   VM_HUGETLB|VM_SHARED|VM_MAYSHARE)



int hugepage_madvise(struct vm_area_struct *vma,

mm/ksm.c

+6 −1
Original line number Diff line number Diff line
@@ -1470,9 +1470,14 @@ int ksm_madvise(struct vm_area_struct *vma, unsigned long start, 
		if (*vm_flags & (VM_MERGEABLE | VM_SHARED  | VM_MAYSHARE   |

				 VM_PFNMAP    | VM_IO      | VM_DONTEXPAND |

				 VM_RESERVED  | VM_HUGETLB | VM_INSERTPAGE |

				 VM_NONLINEAR | VM_MIXEDMAP | VM_SAO))

				 VM_NONLINEAR | VM_MIXEDMAP))

			return 0;		/* just ignore the advice */



#ifdef VM_SAO

		if (*vm_flags & VM_SAO)

			return 0;

#endif



		if (!test_bit(MMF_VM_MERGEABLE, &mm->flags)) {

			err = __ksm_enter(mm);

			if (err)

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