On 12/12/19 9:48 AM, Thomas Hellström (VMware) wrote:
> From: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
>
> The TTM module today uses a hack to be able to set a different page
> protection than struct vm_area_struct::vm_page_prot. To be able to do
> this properly, add the needed vm functionality as vmf_insert_mixed_prot().
>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxx>
> Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
> Cc: Ralph Campbell <rcampbell@xxxxxxxxxx>
> Cc: "Jérôme Glisse" <jglisse@xxxxxxxxxx>
> Cc: "Christian König" <christian.koenig@xxxxxxx>
> Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
> Acked-by: Christian König <christian.koenig@xxxxxxx>
> ---
> include/linux/mm.h | 2 ++
> include/linux/mm_types.h | 7 ++++++-
> mm/memory.c | 43 ++++++++++++++++++++++++++++++++++++----
> 3 files changed, 47 insertions(+), 5 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index cc292273e6ba..29575d3c1e47 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -2548,6 +2548,8 @@ vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
> unsigned long pfn, pgprot_t pgprot);
> vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
> pfn_t pfn);
> +vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr,
> + pfn_t pfn, pgprot_t pgprot);
> vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
> unsigned long addr, pfn_t pfn);
> int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> index 2222fa795284..ac96afdbb4bc 100644
> --- a/include/linux/mm_types.h
> +++ b/include/linux/mm_types.h
> @@ -307,7 +307,12 @@ struct vm_area_struct {
> /* Second cache line starts here. */
>
> struct mm_struct *vm_mm; /* The address space we belong to. */
> - pgprot_t vm_page_prot; /* Access permissions of this VMA. */
> +
> + /*
> + * Access permissions of this VMA.
> + * See vmf_insert_mixed() for discussion.
Typo. will of course be vmf_insert_mixed_prot() in the final version.
