Christophe Leroy <christophe.le...@c-s.fr> writes: > On some CPUs like the 8xx, _PAGE_RW hence _PAGE_WRITE is defined > as 0 and _PAGE_RO has to be set when a page is not writable > > _PAGE_RO is defined by default in pte-common.h, however BOOK3S/64 > doesn't include that file so _PAGE_RO has to be defined explicitly > in book3s/64/pgtable.h > > fixes: a7b9f671f2d14 ("powerpc32: adds handling of _PAGE_RO") > Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> > --- > This patch was initially part of the v1 serie of patchs for providing > hugepage support to the 8xx. As suggested by Aneesh, that serie has > been splited to focus only on hugepage implementation for 8xx. > This patch is a fix and is independant of 8xx hugepage implementation, > allthough it is required to have hugepage support working properly on > the 8xx. > > arch/powerpc/include/asm/book3s/64/pgtable.h | 2 ++ > arch/powerpc/mm/hugetlbpage.c | 2 ++ > 2 files changed, 4 insertions(+) > > diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h > b/arch/powerpc/include/asm/book3s/64/pgtable.h > index 8ec8be9..9fd77f8 100644 > --- a/arch/powerpc/include/asm/book3s/64/pgtable.h > +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h > @@ -6,6 +6,8 @@ > */ > #define _PAGE_BIT_SWAP_TYPE 0 > > +#define _PAGE_RO 0 > + > #define _PAGE_EXEC 0x00001 /* execute permission */ > #define _PAGE_WRITE 0x00002 /* write access allowed */ > #define _PAGE_READ 0x00004 /* read access allowed */ > diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c > index 7372ee1..8a512b1 100644 > --- a/arch/powerpc/mm/hugetlbpage.c > +++ b/arch/powerpc/mm/hugetlbpage.c > @@ -1021,6 +1021,8 @@ int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned > long addr, > mask = _PAGE_PRESENT | _PAGE_READ; > if (write) > mask |= _PAGE_WRITE; > + else > + mask |= _PAGE_RO; > > if ((pte_val(pte) & mask) != mask) > return 0; > --
Can you add the commit message also as code comment ?. It is confusing to find that we do mask = _PAGE_READ and then mask |= _PAGE_RO. Otherwise Reviewed-by: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com> -aneesh