From 1fcfd8db7f82fa1f533a6f0e4155614ff4144d56 Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@redhat.com>
Date: Wed, 9 Sep 2015 15:39:29 -0700
Subject: [PATCH] mm, mpx: add "vm_flags_t vm_flags" arg to do_mmap_pgoff()
Add the additional "vm_flags_t vm_flags" argument to do_mmap_pgoff(),
rename it to do_mmap(), and re-introduce do_mmap_pgoff() as a simple
wrapper on top of do_mmap(). Perhaps we should update the callers of
do_mmap_pgoff() and kill it later.
This way mpx_mmap() can simply call do_mmap(vm_flags => VM_MPX) and do not
play with vm internals.
After this change mmap_region() has a single user outside of mmap.c,
arch/tile/mm/elf.c:arch_setup_additional_pages(). It would be nice to
change arch/tile/ and unexport mmap_region().
[kirill@shutemov.name: fix build]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
arch/x86/mm/mpx.c | 51 +++++++---------------------------------------
include/linux/mm.h | 12 +++++++++--
mm/mmap.c | 10 ++++-----
mm/nommu.c | 19 +++++++++--------
4 files changed, 31 insertions(+), 61 deletions(-)
diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c
index db1b0bc5017c..134948b0926f 100644
--- a/arch/x86/mm/mpx.c
+++ b/arch/x86/mm/mpx.c
@@ -42,58 +42,21 @@ static inline unsigned long mpx_bt_size_bytes(struct mm_struct *mm)
*/
static unsigned long mpx_mmap(unsigned long len)
{
- unsigned long ret;
- unsigned long addr, pgoff;
struct mm_struct *mm = current->mm;
- vm_flags_t vm_flags;
- struct vm_area_struct *vma;
+ unsigned long addr, populate;
/* Only bounds table can be allocated here */
if (len != mpx_bt_size_bytes(mm))
return -EINVAL;
down_write(&mm->mmap_sem);
-
- /* Too many mappings? */
- if (mm->map_count > sysctl_max_map_count) {
- ret = -ENOMEM;
- goto out;
- }
-
- /* Obtain the address to map to. we verify (or select) it and ensure
- * that it represents a valid section of the address space.
- */
- addr = get_unmapped_area(NULL, 0, len, 0, MAP_ANONYMOUS | MAP_PRIVATE);
- if (addr & ~PAGE_MASK) {
- ret = addr;
- goto out;
- }
-
- vm_flags = VM_READ | VM_WRITE | VM_MPX |
- mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
-
- /* Set pgoff according to addr for anon_vma */
- pgoff = addr >> PAGE_SHIFT;
-
- ret = mmap_region(NULL, addr, len, vm_flags, pgoff);
- if (IS_ERR_VALUE(ret))
- goto out;
-
- vma = find_vma(mm, ret);
- if (!vma) {
- ret = -ENOMEM;
- goto out;
- }
-
- if (vm_flags & VM_LOCKED) {
- up_write(&mm->mmap_sem);
- mm_populate(ret, len);
- return ret;
- }
-
-out:
+ addr = do_mmap(NULL, 0, len, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, VM_MPX, 0, &populate);
up_write(&mm->mmap_sem);
- return ret;
+ if (populate)
+ mm_populate(addr, populate);
+
+ return addr;
}
enum reg_type {
diff --git a/include/linux/mm.h b/include/linux/mm.h
index f25a957bf0ab..fda728e3c27d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1873,11 +1873,19 @@ extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned lo
extern unsigned long mmap_region(struct file *file, unsigned long addr,
unsigned long len, vm_flags_t vm_flags, unsigned long pgoff);
-extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
+extern unsigned long do_mmap(struct file *file, unsigned long addr,
unsigned long len, unsigned long prot, unsigned long flags,
- unsigned long pgoff, unsigned long *populate);
+ vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate);
extern int do_munmap(struct mm_struct *, unsigned long, size_t);
+static inline unsigned long
+do_mmap_pgoff(struct file *file, unsigned long addr,
+ unsigned long len, unsigned long prot, unsigned long flags,
+ unsigned long pgoff, unsigned long *populate)
+{
+ return do_mmap(file, addr, len, prot, flags, 0, pgoff, populate);
+}
+
#ifdef CONFIG_MMU
extern int __mm_populate(unsigned long addr, unsigned long len,
int ignore_errors);
diff --git a/mm/mmap.c b/mm/mmap.c
index b6be3249f0a9..c739d6db7193 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1260,14 +1260,12 @@ static inline int mlock_future_check(struct mm_struct *mm,
/*
* The caller must hold down_write(¤t->mm->mmap_sem).
*/
-
-unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
+unsigned long do_mmap(struct file *file, unsigned long addr,
unsigned long len, unsigned long prot,
- unsigned long flags, unsigned long pgoff,
- unsigned long *populate)
+ unsigned long flags, vm_flags_t vm_flags,
+ unsigned long pgoff, unsigned long *populate)
{
struct mm_struct *mm = current->mm;
- vm_flags_t vm_flags;
*populate = 0;
@@ -1311,7 +1309,7 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
* to. we assume access permissions have been handled by the open
* of the memory object, so we don't do any here.
*/
- vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags) |
+ vm_flags |= calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags) |
mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
if (flags & MAP_LOCKED)
diff --git a/mm/nommu.c b/mm/nommu.c
index 1cc0709fcaa5..ab14a2014dea 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1233,18 +1233,19 @@ static int do_mmap_private(struct vm_area_struct *vma,
/*
* handle mapping creation for uClinux
*/
-unsigned long do_mmap_pgoff(struct file *file,
- unsigned long addr,
- unsigned long len,
- unsigned long prot,
- unsigned long flags,
- unsigned long pgoff,
- unsigned long *populate)
+unsigned long do_mmap(struct file *file,
+ unsigned long addr,
+ unsigned long len,
+ unsigned long prot,
+ unsigned long flags,
+ vm_flags_t vm_flags,
+ unsigned long pgoff,
+ unsigned long *populate)
{
struct vm_area_struct *vma;
struct vm_region *region;
struct rb_node *rb;
- unsigned long capabilities, vm_flags, result;
+ unsigned long capabilities, result;
int ret;
*populate = 0;
@@ -1262,7 +1263,7 @@ unsigned long do_mmap_pgoff(struct file *file,
/* we've determined that we can make the mapping, now translate what we
* now know into VMA flags */
- vm_flags = determine_vm_flags(file, prot, flags, capabilities);
+ vm_flags |= determine_vm_flags(file, prot, flags, capabilities);
/* we're going to need to record the mapping */
region = kmem_cache_zalloc(vm_region_jar, GFP_KERNEL);
--
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