Jivin Paul Mundt lays it down ...
> This builds on top of the earlier vmalloc_32_user() work introduced by
> b50731732f926d6c49fd0724616a7344c31cd5cf, as we now have places in the
> nommu allmodconfig that hit up against these missing APIs.
>
> As vmalloc_32_user() is already implemented, this is moved over to
> vmalloc_user() and simply made a wrapper. As all current nommu platforms
> are 32-bit addressable, there's no special casing we have to do for
> ZONE_DMA and things of that nature as per GFP_VMALLOC32.
>
> remap_vmalloc_range() needs to check VM_USERMAP in order to figure out
> whether we permit the remap or not, which means that we also have to
> rework the vmalloc_user() code to grovel for the VMA and set the flag.
Seems fine to me,
Cheers,
Davidm
Acked-by: David McCullough <[email protected]>
> Signed-off-by: Paul Mundt <[email protected]>
>
> ---
>
> mm/nommu.c | 45 ++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 44 insertions(+), 1 deletion(-)
>
> diff --git a/mm/nommu.c b/mm/nommu.c
> index 35622c5..c4768d0 100644
> --- a/mm/nommu.c
> +++ b/mm/nommu.c
> @@ -10,6 +10,7 @@
> * Copyright (c) 2000-2003 David McCullough <[email protected]>
> * Copyright (c) 2000-2001 D Jeff Dionne <[email protected]>
> * Copyright (c) 2002 Greg Ungerer <[email protected]>
> + * Copyright (c) 2007 Paul Mundt <[email protected]>
> */
>
> #include <linux/module.h>
> @@ -183,6 +184,26 @@ void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
> }
> EXPORT_SYMBOL(__vmalloc);
>
> +void *vmalloc_user(unsigned long size)
> +{
> + void *ret;
> +
> + ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
> + PAGE_KERNEL);
> + if (ret) {
> + struct vm_area_struct *vma;
> +
> + down_write(¤t->mm->mmap_sem);
> + vma = find_vma(current->mm, (unsigned long)ret);
> + if (vma)
> + vma->vm_flags |= VM_USERMAP;
> + up_write(¤t->mm->mmap_sem);
> + }
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(vmalloc_user);
> +
> struct page * vmalloc_to_page(void *addr)
> {
> return virt_to_page(addr);
> @@ -253,10 +274,17 @@ EXPORT_SYMBOL(vmalloc_32);
> *
> * The resulting memory area is 32bit addressable and zeroed so it can be
> * mapped to userspace without leaking data.
> + *
> + * VM_USERMAP is set on the corresponding VMA so that subsequent calls to
> + * remap_vmalloc_range() are permissible.
> */
> void *vmalloc_32_user(unsigned long size)
> {
> - return __vmalloc(size, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL);
> + /*
> + * We'll have to sort out the ZONE_DMA bits for 64-bit,
> + * but for now this can simply use vmalloc_user() directly.
> + */
> + return vmalloc_user(size);
> }
> EXPORT_SYMBOL(vmalloc_32_user);
>
> @@ -1213,6 +1241,21 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
> }
> EXPORT_SYMBOL(remap_pfn_range);
>
> +int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
> + unsigned long pgoff)
> +{
> + unsigned int size = vma->vm_end - vma->vm_start;
> +
> + if (!(vma->vm_flags & VM_USERMAP))
> + return -EINVAL;
> +
> + vma->vm_start = (unsigned long)(addr + (pgoff << PAGE_SHIFT));
> + vma->vm_end = vma->vm_start + size;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(remap_vmalloc_range);
> +
> void swap_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
> {
> }
--
David McCullough, [email protected], Ph:+61 734352815
Secure Computing - SnapGear http://www.uCdot.org http://www.cyberguard.com
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
