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Message-Id: <45a7925eab3cc8d1203136f99230ae9f4e5c8c20.1539092112.git.christophe.leroy@c-s.fr>
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From:   Christophe Leroy <christophe.leroy@c-s.fr>
Subject: [PATCH v3 24/24] powerpc/book3s64: Avoid multiple endian conversion
 in pte helpers
To:     Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Dominik Brodowski <linux@dominikbrodowski.net>,
        Geoff Levand <geoff@infradead.org>,
        Jens Axboe <axboe@kernel.dk>,
        Kumar Gala <galak@kernel.crashing.org>,
        Li Yang <leoyang.li@nxp.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Nicholas Piggin <npiggin@gmail.com>,
        Paul Mackerras <paulus@samba.org>,
        Scott Wood <oss@buserror.net>, aneesh.kumar@linux.vnet.ibm.com
Cc:     linux-arm-kernel@lists.infradead.org, linux-block@vger.kernel.org,
        linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org, dri-devel@lists.freedesktop.org
Date:   Tue,  9 Oct 2018 13:52:20 +0000 (UTC)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

In the same spirit as already done in pte query helpers,
this patch changes pte setting helpers to perform endian
conversions on the constants rather than on the pte value.

In the meantime, it changes pte_access_permitted() to use
pte helpers for the same reason.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/include/asm/book3s/64/pgtable.h | 71 +++++++++++++---------------
 1 file changed, 32 insertions(+), 39 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index cf8dbd5f8f03..f0c79f370cf0 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -506,12 +506,12 @@ static inline bool pte_soft_dirty(pte_t pte)
 
 static inline pte_t pte_mksoft_dirty(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_SOFT_DIRTY);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_SOFT_DIRTY));
 }
 
 static inline pte_t pte_clear_soft_dirty(pte_t pte)
 {
-	return __pte(pte_val(pte) & ~_PAGE_SOFT_DIRTY);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_SOFT_DIRTY));
 }
 #endif /* CONFIG_HAVE_ARCH_SOFT_DIRTY */
 
@@ -532,7 +532,7 @@ static inline pte_t pte_mk_savedwrite(pte_t pte)
 	 */
 	VM_BUG_ON((pte_raw(pte) & cpu_to_be64(_PAGE_PRESENT | _PAGE_RWX | _PAGE_PRIVILEGED)) !=
 		  cpu_to_be64(_PAGE_PRESENT | _PAGE_PRIVILEGED));
-	return __pte(pte_val(pte) & ~_PAGE_PRIVILEGED);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_PRIVILEGED));
 }
 
 #define pte_clear_savedwrite pte_clear_savedwrite
@@ -542,14 +542,14 @@ static inline pte_t pte_clear_savedwrite(pte_t pte)
 	 * Used by KSM subsystem to make a protnone pte readonly.
 	 */
 	VM_BUG_ON(!pte_protnone(pte));
-	return __pte(pte_val(pte) | _PAGE_PRIVILEGED);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PRIVILEGED));
 }
 #else
 #define pte_clear_savedwrite pte_clear_savedwrite
 static inline pte_t pte_clear_savedwrite(pte_t pte)
 {
 	VM_WARN_ON(1);
-	return __pte(pte_val(pte) & ~_PAGE_WRITE);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_WRITE));
 }
 #endif /* CONFIG_NUMA_BALANCING */
 
@@ -578,25 +578,22 @@ static inline bool arch_pte_access_permitted(u64 pte, bool write, bool execute)
 }
 #endif /* CONFIG_PPC_MEM_KEYS */
 
+static inline bool pte_user(pte_t pte)
+{
+	return !(pte_raw(pte) & cpu_to_be64(_PAGE_PRIVILEGED));
+}
+
 #define pte_access_permitted pte_access_permitted
 static inline bool pte_access_permitted(pte_t pte, bool write)
 {
-	unsigned long pteval = pte_val(pte);
-	/* Also check for pte_user */
-	unsigned long clear_pte_bits = _PAGE_PRIVILEGED;
 	/*
 	 * _PAGE_READ is needed for any access and will be
 	 * cleared for PROT_NONE
 	 */
-	unsigned long need_pte_bits = _PAGE_PRESENT | _PAGE_READ;
-
-	if (write)
-		need_pte_bits |= _PAGE_WRITE;
-
-	if ((pteval & need_pte_bits) != need_pte_bits)
+	if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte))
 		return false;
 
-	if ((pteval & clear_pte_bits) == clear_pte_bits)
+	if (write && !pte_write(pte))
 		return false;
 
 	return arch_pte_access_permitted(pte_val(pte), write, 0);
@@ -625,32 +622,32 @@ static inline pte_t pte_wrprotect(pte_t pte)
 {
 	if (unlikely(pte_savedwrite(pte)))
 		return pte_clear_savedwrite(pte);
-	return __pte(pte_val(pte) & ~_PAGE_WRITE);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_WRITE));
 }
 
 static inline pte_t pte_exprotect(pte_t pte)
 {
-	return __pte(pte_val(pte) & ~_PAGE_EXEC);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_EXEC));
 }
 
 static inline pte_t pte_mkclean(pte_t pte)
 {
-	return __pte(pte_val(pte) & ~_PAGE_DIRTY);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_DIRTY));
 }
 
 static inline pte_t pte_mkold(pte_t pte)
 {
-	return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_ACCESSED));
 }
 
 static inline pte_t pte_mkexec(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_EXEC);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_EXEC));
 }
 
 static inline pte_t pte_mkpte(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_PTE);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PTE));
 }
 
 static inline pte_t pte_mkwrite(pte_t pte)
@@ -658,22 +655,22 @@ static inline pte_t pte_mkwrite(pte_t pte)
 	/*
 	 * write implies read, hence set both
 	 */
-	return __pte(pte_val(pte) | _PAGE_RW);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_RW));
 }
 
 static inline pte_t pte_mkdirty(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_DIRTY | _PAGE_SOFT_DIRTY);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_DIRTY | _PAGE_SOFT_DIRTY));
 }
 
 static inline pte_t pte_mkyoung(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_ACCESSED);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_ACCESSED));
 }
 
 static inline pte_t pte_mkspecial(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_SPECIAL);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_SPECIAL));
 }
 
 static inline pte_t pte_mkhuge(pte_t pte)
@@ -683,17 +680,17 @@ static inline pte_t pte_mkhuge(pte_t pte)
 
 static inline pte_t pte_mkdevmap(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_SPECIAL|_PAGE_DEVMAP);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_SPECIAL | _PAGE_DEVMAP));
 }
 
 static inline pte_t pte_mkprivileged(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_PRIVILEGED);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PRIVILEGED));
 }
 
 static inline pte_t pte_mkuser(pte_t pte)
 {
-	return __pte(pte_val(pte) & ~_PAGE_PRIVILEGED);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_PRIVILEGED));
 }
 
 /*
@@ -712,12 +709,8 @@ static inline int pte_devmap(pte_t pte)
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 {
 	/* FIXME!! check whether this need to be a conditional */
-	return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
-}
-
-static inline bool pte_user(pte_t pte)
-{
-	return !(pte_raw(pte) & cpu_to_be64(_PAGE_PRIVILEGED));
+	return __pte_raw((pte_raw(pte) & cpu_to_be64(_PAGE_CHG_MASK)) |
+			 cpu_to_be64(pgprot_val(newprot)));
 }
 
 /* Encode and de-code a swap entry */
@@ -760,7 +753,7 @@ static inline bool pte_user(pte_t pte)
 #ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY
 static inline pte_t pte_swp_mksoft_dirty(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_SWP_SOFT_DIRTY);
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_SWP_SOFT_DIRTY));
 }
 
 static inline bool pte_swp_soft_dirty(pte_t pte)
@@ -770,7 +763,7 @@ static inline bool pte_swp_soft_dirty(pte_t pte)
 
 static inline pte_t pte_swp_clear_soft_dirty(pte_t pte)
 {
-	return __pte(pte_val(pte) & ~_PAGE_SWP_SOFT_DIRTY);
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_SWP_SOFT_DIRTY));
 }
 #endif /* CONFIG_HAVE_ARCH_SOFT_DIRTY */
 
@@ -859,10 +852,10 @@ static inline pgprot_t pgprot_writecombine(pgprot_t prot)
  */
 static inline bool pte_ci(pte_t pte)
 {
-	unsigned long pte_v = pte_val(pte);
+	__be64 pte_v = pte_raw(pte);
 
-	if (((pte_v & _PAGE_CACHE_CTL) == _PAGE_TOLERANT) ||
-	    ((pte_v & _PAGE_CACHE_CTL) == _PAGE_NON_IDEMPOTENT))
+	if (((pte_v & cpu_to_be64(_PAGE_CACHE_CTL)) == cpu_to_be64(_PAGE_TOLERANT)) ||
+	    ((pte_v & cpu_to_be64(_PAGE_CACHE_CTL)) == cpu_to_be64(_PAGE_NON_IDEMPOTENT)))
 		return true;
 	return false;
 }
-- 
2.13.3