From 1fcfd8db7f82fa1f533a6f0e4155614ff4144d56 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov 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 Acked-by: Dave Hansen Tested-by: Dave Hansen Signed-off-by: Kirill A. Shutemov Cc: "H. Peter Anvin" Cc: Andy Lutomirski Cc: Ingo Molnar Cc: Minchan Kim Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- 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 @@ enomem: /* * 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); -- 2.20.1