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authorArnd Bergmann <arnd@arndb.de>2012-10-04 22:57:00 +0200
committerArnd Bergmann <arnd@arndb.de>2012-10-04 22:57:51 +0200
commitc37d6154c0b9163c27e53cc1d0be3867b4abd760 (patch)
tree7a24522c56d1cb284dff1d3c225bbdaba0901bb5 /arch/arm64/kernel/kuser32.S
parente7a570ff7dff9af6e54ff5e580a61ec7652137a0 (diff)
parent8a1ab3155c2ac7fbe5f2038d6e26efeb607a1498 (diff)
Merge branch 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers into asm-generic
Patches from David Howells <dhowells@redhat.com>: This is to complete part of the UAPI disintegration for which the preparatory patches were pulled recently. Note that there are some fixup patches which are at the base of the branch aimed at you, plus all arches get the asm-generic branch merged in too. * 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers: UAPI: (Scripted) Disintegrate include/asm-generic UAPI: Fix conditional header installation handling (notably kvm_para.h on m68k) c6x: remove c6x signal.h UAPI: Split compound conditionals containing __KERNEL__ in Arm64 UAPI: Fix the guards on various asm/unistd.h files Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arm64/kernel/kuser32.S')
-rw-r--r--arch/arm64/kernel/kuser32.S77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/arm64/kernel/kuser32.S b/arch/arm64/kernel/kuser32.S
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+++ b/arch/arm64/kernel/kuser32.S
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+/*
+ * Low-level user helpers placed in the vectors page for AArch32.
+ * Based on the kuser helpers in arch/arm/kernel/entry-armv.S.
+ *
+ * Copyright (C) 2005-2011 Nicolas Pitre <nico@fluxnic.net>
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * AArch32 user helpers.
+ *
+ * Each segment is 32-byte aligned and will be moved to the top of the high
+ * vector page. New segments (if ever needed) must be added in front of
+ * existing ones. This mechanism should be used only for things that are
+ * really small and justified, and not be abused freely.
+ *
+ * See Documentation/arm/kernel_user_helpers.txt for formal definitions.
+ */
+ .align 5
+ .globl __kuser_helper_start
+__kuser_helper_start:
+
+__kuser_cmpxchg64: // 0xffff0f60
+ .inst 0xe92d00f0 // push {r4, r5, r6, r7}
+ .inst 0xe1c040d0 // ldrd r4, r5, [r0]
+ .inst 0xe1c160d0 // ldrd r6, r7, [r1]
+ .inst 0xf57ff05f // dmb sy
+ .inst 0xe1b20f9f // 1: ldrexd r0, r1, [r2]
+ .inst 0xe0303004 // eors r3, r0, r4
+ .inst 0x00313005 // eoreqs r3, r1, r5
+ .inst 0x01a23f96 // strexdeq r3, r6, [r2]
+ .inst 0x03330001 // teqeq r3, #1
+ .inst 0x0afffff9 // beq 1b
+ .inst 0xf57ff05f // dmb sy
+ .inst 0xe2730000 // rsbs r0, r3, #0
+ .inst 0xe8bd00f0 // pop {r4, r5, r6, r7}
+ .inst 0xe12fff1e // bx lr
+
+ .align 5
+__kuser_memory_barrier: // 0xffff0fa0
+ .inst 0xf57ff05f // dmb sy
+ .inst 0xe12fff1e // bx lr
+
+ .align 5
+__kuser_cmpxchg: // 0xffff0fc0
+ .inst 0xf57ff05f // dmb sy
+ .inst 0xe1923f9f // 1: ldrex r3, [r2]
+ .inst 0xe0533000 // subs r3, r3, r0
+ .inst 0x01823f91 // strexeq r3, r1, [r2]
+ .inst 0x03330001 // teqeq r3, #1
+ .inst 0x0afffffa // beq 1b
+ .inst 0xe2730000 // rsbs r0, r3, #0
+ .inst 0xeaffffef // b <__kuser_memory_barrier>
+
+ .align 5
+__kuser_get_tls: // 0xffff0fe0
+ .inst 0xee1d0f70 // mrc p15, 0, r0, c13, c0, 3
+ .inst 0xe12fff1e // bx lr
+ .rep 5
+ .word 0
+ .endr
+
+__kuser_helper_version: // 0xffff0ffc
+ .word ((__kuser_helper_end - __kuser_helper_start) >> 5)
+ .globl __kuser_helper_end
+__kuser_helper_end: