powerpc/mm: move setting pte specific flags to pfn_pte

powerpc used to set the pte specific flags in set_pte_at().  This is
different from other architectures.  To be consistent with other
architecture update pfn_pte to set _PAGE_PTE on ppc64.  Also, drop now
unused pte_mkpte.

We add a VM_WARN_ON() to catch the usage of calling set_pte_at() without
setting _PAGE_PTE bit.  We will remove that after a few releases.

With respect to huge pmd entries, pmd_mkhuge() takes care of adding the
_PAGE_PTE bit.

[akpm@linux-foundation.org: whitespace fix, per Christophe]

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lkml.kernel.org/r/20200902114222.181353-3-aneesh.kumar@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index e9ada44..f6d2c44 100644 (file)
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -615,7 +615,7 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
        VM_BUG_ON(pfn >> (64 - PAGE_SHIFT));
        VM_BUG_ON((pfn << PAGE_SHIFT) & ~PTE_RPN_MASK);
 
-       return __pte(((pte_basic_t)pfn << PAGE_SHIFT) | pgprot_val(pgprot));
+       return __pte(((pte_basic_t)pfn << PAGE_SHIFT) | pgprot_val(pgprot) | _PAGE_PTE);
 }
 
 static inline unsigned long pte_pfn(pte_t pte)
@@ -651,11 +651,6 @@ static inline pte_t pte_mkexec(pte_t pte)
        return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_EXEC));
 }
 
-static inline pte_t pte_mkpte(pte_t pte)
-{
-       return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PTE));
-}
-
 static inline pte_t pte_mkwrite(pte_t pte)
 {
        /*
@@ -819,6 +814,14 @@ static inline int pte_none(pte_t pte)
 static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
                                pte_t *ptep, pte_t pte, int percpu)
 {
+
+       VM_WARN_ON(!(pte_raw(pte) & cpu_to_be64(_PAGE_PTE)));
+       /*
+        * Keep the _PAGE_PTE added till we are sure we handle _PAGE_PTE
+        * in all the callers.
+        */
+       pte = __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PTE));
+
        if (radix_enabled())
                return radix__set_pte_at(mm, addr, ptep, pte, percpu);
        return hash__set_pte_at(mm, addr, ptep, pte, percpu);

diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
index 4b7c347..6277e75 100644 (file)
--- a/arch/powerpc/include/asm/nohash/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/pgtable.h
@@ -140,11 +140,6 @@ static inline pte_t pte_mkold(pte_t pte)
        return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
 }
 
-static inline pte_t pte_mkpte(pte_t pte)
-{
-       return pte;
-}
-
 static inline pte_t pte_mkspecial(pte_t pte)
 {
        return __pte(pte_val(pte) | _PAGE_SPECIAL);

diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index 9c0547d..ab57b07 100644 (file)
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -184,9 +184,6 @@ void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
         */
        VM_WARN_ON(pte_hw_valid(*ptep) && !pte_protnone(*ptep));
 
-       /* Add the pte bit when trying to set a pte */
-       pte = pte_mkpte(pte);
-
        /* Note: mm->context.id might not yet have been assigned as
         * this context might not have been activated yet when this
         * is called.
@@ -275,8 +272,6 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_
         */
        VM_WARN_ON(pte_hw_valid(*ptep) && !pte_protnone(*ptep));
 
-       pte = pte_mkpte(pte);
-
        pte = set_pte_filter(pte);
 
        val = pte_val(pte);