[PATCH 3/3] arm64: remove the rest of asm-uaccess.h

[Pavel Tatashin]

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

Replace them with C wrappers and call C functions from
kernel_entry and kernel_exit.

Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
---
 arch/arm64/include/asm/asm-uaccess.h | 38 ----------------------------
 arch/arm64/kernel/entry.S            |  6 ++---
 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 -
 arch/arm64/mm/context.c              | 12 +++++++++
 arch/xtensa/kernel/coprocessor.S     |  1 -
 9 files changed, 19 insertions(+), 47 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 8f763e5b41b1..000000000000
--- a/arch/arm64/include/asm/asm-uaccess.h
+++ /dev/null
@@ -1,38 +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 583f71abbe98..c7b571e6d0f2 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>
 
 /*
@@ -219,7 +219,7 @@ alternative_else_nop_endif
 	and	x23, x23, #~PSR_PAN_BIT		// Clear the emulated PAN in the saved SPSR
 	.endif
 
-	__uaccess_ttbr0_disable x21
+	bl __uaccess_ttbr0_disable_c
 1:
 #endif
 
@@ -293,7 +293,7 @@ alternative_else_nop_endif
 	tbnz	x22, #22, 1f			// Skip re-enabling TTBR0 access if the PSR_PAN_BIT is set
 	.endif
 
-	__uaccess_ttbr0_enable x0, x1
+	bl	__uaccess_ttbr0_enable_c
 
 	.if	\el == 0
 	/*
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 408d317a47d2..7940d6ef5da5 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>
 
 /*
  *	__arch_flush_icache_range(start,end)
diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c
index b5e329fde2dd..4fc32c504dea 100644
--- a/arch/arm64/mm/context.c
+++ b/arch/arm64/mm/context.c
@@ -237,6 +237,18 @@ void check_and_switch_context(struct mm_struct *mm, unsigned int cpu)
 		cpu_switch_mm(mm->pgd, mm);
 }
 
+#ifdef CONFIG_ARM64_SW_TTBR0_PAN
+asmlinkage void __uaccess_ttbr0_enable_c(void)
+{
+	__uaccess_ttbr0_enable();
+}
+
+asmlinkage void __uaccess_ttbr0_disable_c(void)
+{
+	__uaccess_ttbr0_disable();
+}
+#endif
+
 /* Errata workaround post TTBRx_EL1 update. */
 asmlinkage void post_ttbr_update_workaround(void)
 {
diff --git a/arch/xtensa/kernel/coprocessor.S b/arch/xtensa/kernel/coprocessor.S
index 80828b95a51f..6329d17e2aa0 100644
--- a/arch/xtensa/kernel/coprocessor.S
+++ b/arch/xtensa/kernel/coprocessor.S
@@ -18,7 +18,6 @@
 #include <asm/processor.h>
 #include <asm/coprocessor.h>
 #include <asm/thread_info.h>
-#include <asm/asm-uaccess.h>
 #include <asm/unistd.h>
 #include <asm/ptrace.h>
 #include <asm/current.h>
-- 
2.24.0