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

From: Pavel Tatashin
Date: Wed Nov 27 2019 - 13:45:06 EST


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@xxxxxxxxxx>
---
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 583f71abbe98..446d90ab31af 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>

/*
@@ -143,6 +143,31 @@ 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 a48b6dba304e..f7130c30d6e3 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_icache_range(start,end)
--
2.24.0