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Commit b73781c8 authored by Jeff Dike's avatar Jeff Dike Committed by Linus Torvalds
Browse files

[PATCH] uml: MADV_REMOVE fixes 



MADV_REMOVE fixes - change the test mapping to be MAP_SHARED instead of
MAP_PRIVATE, as MADV_REMOVE on MAP_PRIVATE maps won't work.  Also, use
the kernel's definition of MADV_REMOVE instead of hardcoding it if there
isn't a libc definition.

Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 676ff453

arch/um/include/sysdep-i386/kernel-offsets.h

+2 −0
Original line number Diff line number Diff line 
#include <linux/stddef.h>

#include <linux/sched.h>

#include <linux/elf.h>

#include <asm/mman.h>



#define DEFINE(sym, val) \

	asm volatile("\n->" #sym " %0 " #val : : "i" (val))
@@ -16,6 +17,7 @@ 
void foo(void)

{

	OFFSET(HOST_TASK_DEBUGREGS, task_struct, thread.arch.debugregs);

	DEFINE(KERNEL_MADV_REMOVE, MADV_REMOVE);

#ifdef CONFIG_MODE_TT

	OFFSET(HOST_TASK_EXTERN_PID, task_struct, thread.mode.tt.extern_pid);

#endif

arch/um/include/sysdep-x86_64/kernel-offsets.h

+2 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
#include <linux/time.h>

#include <linux/elf.h>

#include <asm/page.h>

#include <asm/mman.h>



#define DEFINE(sym, val) \

	asm volatile("\n->" #sym " %0 " #val : : "i" (val))
@@ -18,6 +19,7 @@ 


void foo(void)

{

	DEFINE(KERNEL_MADV_REMOVE, MADV_REMOVE);

#ifdef CONFIG_MODE_TT

	OFFSET(HOST_TASK_EXTERN_PID, task_struct, thread.mode.tt.extern_pid);

#endif

arch/um/os-Linux/process.c

+2 −2
Original line number Diff line number Diff line
@@ -190,7 +190,7 @@ int os_unmap_memory(void *addr, int len) 
}



#ifndef MADV_REMOVE

#define MADV_REMOVE	0x5		/* remove these pages & resources */

#define MADV_REMOVE KERNEL_MADV_REMOVE

#endif



int os_drop_memory(void *addr, int length)
@@ -216,7 +216,7 @@ int can_drop_memory(void) 
	}



	addr = mmap64(NULL, UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,

		      MAP_PRIVATE, fd, 0);

		      MAP_SHARED, fd, 0);

	if(addr == MAP_FAILED){

		printk("Mapping test memory file failed, err = %d\n", -errno);

		return 0;