[PATCH v5 6/6] arm64: remove the rest of asm-uaccess.h

Pavel Tatashin pasha.tatashin at soleen.com
Thu Jan 2 13:13:57 PST 2020


The __uaccess_ttbr0_disable and __uaccess_ttbr0_enable,
are the last two macros defined in asm-uaccess.h.

For now move them to entry.S where they are used. Eventually,
these macros should be replaced with C wrappers to reduce the
maintenance burden.

Also, once these macros are unified with the C counterparts, it
is a good idea to check that PAN is in correct state on every
enable/disable calls.

Signed-off-by: Pavel Tatashin <pasha.tatashin at soleen.com>
---
 arch/arm64/include/asm/asm-uaccess.h | 39 ----------------------------
 arch/arm64/kernel/entry.S            | 27 ++++++++++++++++++-
 arch/arm64/lib/clear_user.S          |  2 +-
 arch/arm64/lib/copy_from_user.S      |  2 +-
 arch/arm64/lib/copy_in_user.S        |  2 +-
 arch/arm64/lib/copy_to_user.S        |  2 +-
 arch/arm64/mm/cache.S                |  1 -
 7 files changed, 30 insertions(+), 45 deletions(-)
 delete mode 100644 arch/arm64/include/asm/asm-uaccess.h

diff --git a/arch/arm64/include/asm/asm-uaccess.h b/arch/arm64/include/asm/asm-uaccess.h
deleted file mode 100644
index fba2a69f7fef..000000000000
--- a/arch/arm64/include/asm/asm-uaccess.h
+++ /dev/null
@@ -1,39 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __ASM_ASM_UACCESS_H
-#define __ASM_ASM_UACCESS_H
-
-#include <asm/alternative.h>
-#include <asm/kernel-pgtable.h>
-#include <asm/mmu.h>
-#include <asm/sysreg.h>
-#include <asm/assembler.h>
-
-/*
- * User access enabling/disabling macros.
- */
-#ifdef CONFIG_ARM64_SW_TTBR0_PAN
-	.macro	__uaccess_ttbr0_disable, tmp1
-	mrs	\tmp1, ttbr1_el1			// swapper_pg_dir
-	bic	\tmp1, \tmp1, #TTBR_ASID_MASK
-	sub	\tmp1, \tmp1, #RESERVED_TTBR0_SIZE	// reserved_ttbr0 just before swapper_pg_dir
-	msr	ttbr0_el1, \tmp1			// set reserved TTBR0_EL1
-	isb
-	add	\tmp1, \tmp1, #RESERVED_TTBR0_SIZE
-	msr	ttbr1_el1, \tmp1		// set reserved ASID
-	isb
-	.endm
-
-	.macro	__uaccess_ttbr0_enable, tmp1, tmp2
-	get_current_task \tmp1
-	ldr	\tmp1, [\tmp1, #TSK_TI_TTBR0]	// load saved TTBR0_EL1
-	mrs	\tmp2, ttbr1_el1
-	extr    \tmp2, \tmp2, \tmp1, #48
-	ror     \tmp2, \tmp2, #16
-	msr	ttbr1_el1, \tmp2		// set the active ASID
-	isb
-	msr	ttbr0_el1, \tmp1		// set the non-PAN TTBR0_EL1
-	isb
-	.endm
-#endif
-
-#endif
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 7c6a0a41676f..cc6c0dbb7734 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -22,8 +22,8 @@
 #include <asm/mmu.h>
 #include <asm/processor.h>
 #include <asm/ptrace.h>
+#include <asm/kernel-pgtable.h>
 #include <asm/thread_info.h>
-#include <asm/asm-uaccess.h>
 #include <asm/unistd.h>
 
 /*
@@ -144,6 +144,31 @@ alternative_cb_end
 #endif
 	.endm
 
+#ifdef CONFIG_ARM64_SW_TTBR0_PAN
+	.macro	__uaccess_ttbr0_disable, tmp1
+	mrs	\tmp1, ttbr1_el1		// swapper_pg_dir
+	bic	\tmp1, \tmp1, #TTBR_ASID_MASK
+	sub	\tmp1, \tmp1, #RESERVED_TTBR0_SIZE // reserved_ttbr0 just before swapper_pg_dir
+	msr	ttbr0_el1, \tmp1		// set reserved TTBR0_EL1
+	isb
+	add	\tmp1, \tmp1, #RESERVED_TTBR0_SIZE
+	msr	ttbr1_el1, \tmp1		// set reserved ASID
+	isb
+	.endm
+
+	.macro	__uaccess_ttbr0_enable, tmp1, tmp2
+	get_current_task \tmp1
+	ldr	\tmp1, [\tmp1, #TSK_TI_TTBR0]	// load saved TTBR0_EL1
+	mrs	\tmp2, ttbr1_el1
+	extr	\tmp2, \tmp2, \tmp1, #48
+	ror	\tmp2, \tmp2, #16
+	msr	ttbr1_el1, \tmp2		// set the active ASID
+	isb
+	msr	ttbr0_el1, \tmp1		// set the non-PAN TTBR0_EL1
+	isb
+	.endm
+#endif
+
 	.macro	kernel_entry, el, regsize = 64
 	.if	\regsize == 32
 	mov	w0, w0				// zero upper 32 bits of x0
diff --git a/arch/arm64/lib/clear_user.S b/arch/arm64/lib/clear_user.S
index aeafc03e961a..b0b4a86a09e2 100644
--- a/arch/arm64/lib/clear_user.S
+++ b/arch/arm64/lib/clear_user.S
@@ -6,7 +6,7 @@
  */
 #include <linux/linkage.h>
 
-#include <asm/asm-uaccess.h>
+#include <asm/alternative.h>
 #include <asm/assembler.h>
 
 	.text
diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S
index ebb3c06cbb5d..142bc7505518 100644
--- a/arch/arm64/lib/copy_from_user.S
+++ b/arch/arm64/lib/copy_from_user.S
@@ -5,7 +5,7 @@
 
 #include <linux/linkage.h>
 
-#include <asm/asm-uaccess.h>
+#include <asm/alternative.h>
 #include <asm/assembler.h>
 #include <asm/cache.h>
 
diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S
index 3d8153a1ebce..04dc48ca26f7 100644
--- a/arch/arm64/lib/copy_in_user.S
+++ b/arch/arm64/lib/copy_in_user.S
@@ -7,7 +7,7 @@
 
 #include <linux/linkage.h>
 
-#include <asm/asm-uaccess.h>
+#include <asm/alternative.h>
 #include <asm/assembler.h>
 #include <asm/cache.h>
 
diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S
index 357eae2c18eb..8f3218ae88ab 100644
--- a/arch/arm64/lib/copy_to_user.S
+++ b/arch/arm64/lib/copy_to_user.S
@@ -5,7 +5,7 @@
 
 #include <linux/linkage.h>
 
-#include <asm/asm-uaccess.h>
+#include <asm/alternative.h>
 #include <asm/assembler.h>
 #include <asm/cache.h>
 
diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S
index 0093bb9fcd12..627be857b8d0 100644
--- a/arch/arm64/mm/cache.S
+++ b/arch/arm64/mm/cache.S
@@ -12,7 +12,6 @@
 #include <asm/assembler.h>
 #include <asm/cpufeature.h>
 #include <asm/alternative.h>
-#include <asm/asm-uaccess.h>
 
 /*
  *	__asm_flush_cache_user_range(start,end)
-- 
2.17.1




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