From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>,
Michael Ellerman <mpe@ellerman.id.au>
Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH v2 3/5] powerpc/32s: Refactor update of user segment registers
Date: Fri, 7 May 2021 07:03:14 +0000 (UTC) [thread overview]
Message-ID: <794ec59dc94cbc35a1ff0b11100f152e3af05634.1620370984.git.christophe.leroy@csgroup.eu> (raw)
In-Reply-To: <9c5f23642ac5900c8e83da795afac7041bf87cf6.1620370984.git.christophe.leroy@csgroup.eu>
KUEP implements the update of user segment registers.
Move it into mmu-hash.h in order to use it from other places.
And inline kuep_lock() and kuep_unlock() and remove kuep.c
inlining kuep_lock() is important for system_call_exception(),
otherwise system_call_exception() has to save into stack the
system call parameters that are used just after, and doing
that takes more instructions than kuep_lock() itself.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/book3s/32/mmu-hash.h | 27 +++++++++++++
arch/powerpc/include/asm/kup.h | 11 ++++-
arch/powerpc/mm/book3s32/Makefile | 1 -
arch/powerpc/mm/book3s32/kuep.c | 40 -------------------
4 files changed, 36 insertions(+), 43 deletions(-)
delete mode 100644 arch/powerpc/mm/book3s32/kuep.c
diff --git a/arch/powerpc/include/asm/book3s/32/mmu-hash.h b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
index b85f8e114a9c..cc0284bbac86 100644
--- a/arch/powerpc/include/asm/book3s/32/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
@@ -102,6 +102,33 @@ extern s32 patch__hash_page_B, patch__hash_page_C;
extern s32 patch__flush_hash_A0, patch__flush_hash_A1, patch__flush_hash_A2;
extern s32 patch__flush_hash_B;
+#include <asm/reg.h>
+#include <asm/task_size_32.h>
+
+#define UPDATE_TWO_USER_SEGMENTS(n) do { \
+ if (TASK_SIZE > ((n) << 28)) \
+ mtsr(val1, (n) << 28); \
+ if (TASK_SIZE > (((n) + 1) << 28)) \
+ mtsr(val2, ((n) + 1) << 28); \
+ val1 = (val1 + 0x222) & 0xf0ffffff; \
+ val2 = (val2 + 0x222) & 0xf0ffffff; \
+} while (0)
+
+static __always_inline void update_user_segments(u32 val)
+{
+ int val1 = val;
+ int val2 = (val + 0x111) & 0xf0ffffff;
+
+ UPDATE_TWO_USER_SEGMENTS(0);
+ UPDATE_TWO_USER_SEGMENTS(2);
+ UPDATE_TWO_USER_SEGMENTS(4);
+ UPDATE_TWO_USER_SEGMENTS(6);
+ UPDATE_TWO_USER_SEGMENTS(8);
+ UPDATE_TWO_USER_SEGMENTS(10);
+ UPDATE_TWO_USER_SEGMENTS(12);
+ UPDATE_TWO_USER_SEGMENTS(14);
+}
+
#endif /* !__ASSEMBLY__ */
/* We happily ignore the smaller BATs on 601, we don't actually use
diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h
index ec96232529ac..1da9fed5c321 100644
--- a/arch/powerpc/include/asm/kup.h
+++ b/arch/powerpc/include/asm/kup.h
@@ -47,8 +47,15 @@ static inline void setup_kuep(bool disabled) { }
#endif /* CONFIG_PPC_KUEP */
#if defined(CONFIG_PPC_KUEP) && defined(CONFIG_PPC_BOOK3S_32)
-void kuep_lock(void);
-void kuep_unlock(void);
+static inline void kuep_lock(void)
+{
+ update_user_segments(mfsr(0) | SR_NX);
+}
+
+static inline void kuep_unlock(void)
+{
+ update_user_segments(mfsr(0) & ~SR_NX);
+}
#else
static inline void kuep_lock(void) { }
static inline void kuep_unlock(void) { }
diff --git a/arch/powerpc/mm/book3s32/Makefile b/arch/powerpc/mm/book3s32/Makefile
index 7f0c8a78ba0c..446d9de88ce4 100644
--- a/arch/powerpc/mm/book3s32/Makefile
+++ b/arch/powerpc/mm/book3s32/Makefile
@@ -9,4 +9,3 @@ endif
obj-y += mmu.o mmu_context.o
obj-$(CONFIG_PPC_BOOK3S_603) += nohash_low.o
obj-$(CONFIG_PPC_BOOK3S_604) += hash_low.o tlb.o
-obj-$(CONFIG_PPC_KUEP) += kuep.o
diff --git a/arch/powerpc/mm/book3s32/kuep.c b/arch/powerpc/mm/book3s32/kuep.c
deleted file mode 100644
index 8ed1b8634839..000000000000
--- a/arch/powerpc/mm/book3s32/kuep.c
+++ /dev/null
@@ -1,40 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-
-#include <asm/kup.h>
-#include <asm/reg.h>
-#include <asm/task_size_32.h>
-#include <asm/mmu.h>
-
-#define KUEP_UPDATE_TWO_USER_SEGMENTS(n) do { \
- if (TASK_SIZE > ((n) << 28)) \
- mtsr(val1, (n) << 28); \
- if (TASK_SIZE > (((n) + 1) << 28)) \
- mtsr(val2, ((n) + 1) << 28); \
- val1 = (val1 + 0x222) & 0xf0ffffff; \
- val2 = (val2 + 0x222) & 0xf0ffffff; \
-} while (0)
-
-static __always_inline void kuep_update(u32 val)
-{
- int val1 = val;
- int val2 = (val + 0x111) & 0xf0ffffff;
-
- KUEP_UPDATE_TWO_USER_SEGMENTS(0);
- KUEP_UPDATE_TWO_USER_SEGMENTS(2);
- KUEP_UPDATE_TWO_USER_SEGMENTS(4);
- KUEP_UPDATE_TWO_USER_SEGMENTS(6);
- KUEP_UPDATE_TWO_USER_SEGMENTS(8);
- KUEP_UPDATE_TWO_USER_SEGMENTS(10);
- KUEP_UPDATE_TWO_USER_SEGMENTS(12);
- KUEP_UPDATE_TWO_USER_SEGMENTS(14);
-}
-
-void kuep_lock(void)
-{
- kuep_update(mfsr(0) | SR_NX);
-}
-
-void kuep_unlock(void)
-{
- kuep_update(mfsr(0) & ~SR_NX);
-}
--
2.25.0
next prev parent reply other threads:[~2021-05-07 7:03 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-07 7:03 [PATCH v2 1/5] powerpc/nohash: Refactor update of BDI2000 pointers in switch_mmu_context() Christophe Leroy
2021-05-07 7:03 ` [PATCH v2 2/5] powerpc/nohash: Convert set_context() to C Christophe Leroy
2021-05-07 7:03 ` Christophe Leroy [this message]
2021-05-07 7:03 ` [PATCH v2 4/5] powerpc/32s: Convert switch_mmu_context() " Christophe Leroy
2021-05-07 7:03 ` [PATCH v2 5/5] powerpc/32s: Simplify calculation of segment register content Christophe Leroy
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