On Thu, Jul 16, 2015 at 6:26 PM, Oleg Nesterov <oleg@xxxxxxxxxx> wrote: > 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. It seems that the version of this patch in linux-next breaks all nommu builds (m86k, some arm, etc). mm/nommu.c: In function 'do_mmap': mm/nommu.c:1248:30: error: 'vm_flags' redeclared as different kind of symbol mm/nommu.c:1241:15: note: previous definition of 'vm_flags' was here scripts/Makefile.build:258: recipe for target 'mm/nommu.o' failed http://kisskb.ellerman.id.au/kisskb/buildresult/12470285/ Bisect says: 31705a3a633bb63683918f055fe6032939672b61 is the first bad commit commit 31705a3a633bb63683918f055fe6032939672b61 Author: Oleg Nesterov <oleg@xxxxxxxxxx> Date: Fri Jul 24 09:20:30 2015 +1000 mm, mpx: add "vm_flags_t vm_flags" arg to do_mmap_pgoff() Paul. -- > > 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(). > > Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> > --- > arch/x86/mm/mpx.c | 51 +++++++-------------------------------------------- > include/linux/mm.h | 12 ++++++++++-- > mm/mmap.c | 10 ++++------ > mm/nommu.c | 15 ++++++++------- > 4 files changed, 29 insertions(+), 59 deletions(-) > > diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c > index 4d1c11c..fdbd3e0 100644 > --- a/arch/x86/mm/mpx.c > +++ b/arch/x86/mm/mpx.c > @@ -24,58 +24,21 @@ > */ > 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 and bounds directory can be allocated here */ > if (len != MPX_BD_SIZE_BYTES && len != MPX_BT_SIZE_BYTES) > 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 0207ffa..1f0a56e 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -1849,11 +1849,19 @@ 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 2185cd9..2f36ebc 100644 > --- a/mm/mmap.c > +++ b/mm/mmap.c > @@ -1247,14 +1247,12 @@ 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; > > @@ -1298,7 +1296,7 @@ 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 e544508..e3026fd 100644 > --- a/mm/nommu.c > +++ b/mm/nommu.c > @@ -1271,13 +1271,14 @@ 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; > -- > 1.5.5.1 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
