From: Santosh Sivaraj <santosh@fossix.org>
To: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
Linux Kernel <linux-kernel@vger.kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
Mahesh Salgaonkar <mahesh@linux.ibm.com>,
Reza Arbab <arbab@linux.ibm.com>,
Chandan Rajendra <chandan@linux.ibm.com>,
Nicholas Piggin <npiggin@gmail.com>,
Michael Ellerman <mpe@ellerman.id.au>,
Balbir Singh <bsingharora@gmail.com>
Subject: [PATCH v11 6/7] powerpc/memcpy: Add memcpy_mcsafe for pmem
Date: Tue, 20 Aug 2019 13:43:51 +0530 [thread overview]
Message-ID: <20190820081352.8641-7-santosh@fossix.org> (raw)
In-Reply-To: <20190820081352.8641-1-santosh@fossix.org>
From: Balbir Singh <bsingharora@gmail.com>
The pmem infrastructure uses memcpy_mcsafe in the pmem layer so as to
convert machine check exceptions into a return value on failure in case
a machine check exception is encountered during the memcpy. The return
value is the number of bytes remaining to be copied.
This patch largely borrows from the copyuser_power7 logic and does not add
the VMX optimizations, largely to keep the patch simple. If needed those
optimizations can be folded in.
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[arbab@linux.ibm.com: Added symbol export]
Co-developed-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
---
arch/powerpc/include/asm/string.h | 2 +
arch/powerpc/lib/Makefile | 2 +-
arch/powerpc/lib/memcpy_mcsafe_64.S | 242 ++++++++++++++++++++++++++++
3 files changed, 245 insertions(+), 1 deletion(-)
create mode 100644 arch/powerpc/lib/memcpy_mcsafe_64.S
diff --git a/arch/powerpc/include/asm/string.h b/arch/powerpc/include/asm/string.h
index 9bf6dffb4090..b72692702f35 100644
--- a/arch/powerpc/include/asm/string.h
+++ b/arch/powerpc/include/asm/string.h
@@ -53,7 +53,9 @@ void *__memmove(void *to, const void *from, __kernel_size_t n);
#ifndef CONFIG_KASAN
#define __HAVE_ARCH_MEMSET32
#define __HAVE_ARCH_MEMSET64
+#define __HAVE_ARCH_MEMCPY_MCSAFE
+extern int memcpy_mcsafe(void *dst, const void *src, __kernel_size_t sz);
extern void *__memset16(uint16_t *, uint16_t v, __kernel_size_t);
extern void *__memset32(uint32_t *, uint32_t v, __kernel_size_t);
extern void *__memset64(uint64_t *, uint64_t v, __kernel_size_t);
diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
index eebc782d89a5..fa6b1b657b43 100644
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile
@@ -39,7 +39,7 @@ obj-$(CONFIG_PPC_BOOK3S_64) += copyuser_power7.o copypage_power7.o \
memcpy_power7.o
obj64-y += copypage_64.o copyuser_64.o mem_64.o hweight_64.o \
- memcpy_64.o pmem.o
+ memcpy_64.o pmem.o memcpy_mcsafe_64.o
obj64-$(CONFIG_SMP) += locks.o
obj64-$(CONFIG_ALTIVEC) += vmx-helper.o
diff --git a/arch/powerpc/lib/memcpy_mcsafe_64.S b/arch/powerpc/lib/memcpy_mcsafe_64.S
new file mode 100644
index 000000000000..949976dc115d
--- /dev/null
+++ b/arch/powerpc/lib/memcpy_mcsafe_64.S
@@ -0,0 +1,242 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) IBM Corporation, 2011
+ * Derived from copyuser_power7.s by Anton Blanchard <anton@au.ibm.com>
+ * Author - Balbir Singh <bsingharora@gmail.com>
+ */
+#include <asm/ppc_asm.h>
+#include <asm/errno.h>
+#include <asm/export.h>
+
+ .macro err1
+100:
+ EX_TABLE(100b,.Ldo_err1)
+ .endm
+
+ .macro err2
+200:
+ EX_TABLE(200b,.Ldo_err2)
+ .endm
+
+ .macro err3
+300: EX_TABLE(300b,.Ldone)
+ .endm
+
+.Ldo_err2:
+ ld r22,STK_REG(R22)(r1)
+ ld r21,STK_REG(R21)(r1)
+ ld r20,STK_REG(R20)(r1)
+ ld r19,STK_REG(R19)(r1)
+ ld r18,STK_REG(R18)(r1)
+ ld r17,STK_REG(R17)(r1)
+ ld r16,STK_REG(R16)(r1)
+ ld r15,STK_REG(R15)(r1)
+ ld r14,STK_REG(R14)(r1)
+ addi r1,r1,STACKFRAMESIZE
+.Ldo_err1:
+ /* Do a byte by byte copy to get the exact remaining size */
+ mtctr r7
+46:
+err3; lbz r0,0(r4)
+ addi r4,r4,1
+err3; stb r0,0(r3)
+ addi r3,r3,1
+ bdnz 46b
+ li r3,0
+ blr
+
+.Ldone:
+ mfctr r3
+ blr
+
+
+_GLOBAL(memcpy_mcsafe)
+ mr r7,r5
+ cmpldi r5,16
+ blt .Lshort_copy
+
+.Lcopy:
+ /* Get the source 8B aligned */
+ neg r6,r4
+ mtocrf 0x01,r6
+ clrldi r6,r6,(64-3)
+
+ bf cr7*4+3,1f
+err1; lbz r0,0(r4)
+ addi r4,r4,1
+err1; stb r0,0(r3)
+ addi r3,r3,1
+ subi r7,r7,1
+
+1: bf cr7*4+2,2f
+err1; lhz r0,0(r4)
+ addi r4,r4,2
+err1; sth r0,0(r3)
+ addi r3,r3,2
+ subi r7,r7,2
+
+2: bf cr7*4+1,3f
+err1; lwz r0,0(r4)
+ addi r4,r4,4
+err1; stw r0,0(r3)
+ addi r3,r3,4
+ subi r7,r7,4
+
+3: sub r5,r5,r6
+ cmpldi r5,128
+ blt 5f
+
+ mflr r0
+ stdu r1,-STACKFRAMESIZE(r1)
+ std r14,STK_REG(R14)(r1)
+ std r15,STK_REG(R15)(r1)
+ std r16,STK_REG(R16)(r1)
+ std r17,STK_REG(R17)(r1)
+ std r18,STK_REG(R18)(r1)
+ std r19,STK_REG(R19)(r1)
+ std r20,STK_REG(R20)(r1)
+ std r21,STK_REG(R21)(r1)
+ std r22,STK_REG(R22)(r1)
+ std r0,STACKFRAMESIZE+16(r1)
+
+ srdi r6,r5,7
+ mtctr r6
+
+ /* Now do cacheline (128B) sized loads and stores. */
+ .align 5
+4:
+err2; ld r0,0(r4)
+err2; ld r6,8(r4)
+err2; ld r8,16(r4)
+err2; ld r9,24(r4)
+err2; ld r10,32(r4)
+err2; ld r11,40(r4)
+err2; ld r12,48(r4)
+err2; ld r14,56(r4)
+err2; ld r15,64(r4)
+err2; ld r16,72(r4)
+err2; ld r17,80(r4)
+err2; ld r18,88(r4)
+err2; ld r19,96(r4)
+err2; ld r20,104(r4)
+err2; ld r21,112(r4)
+err2; ld r22,120(r4)
+ addi r4,r4,128
+err2; std r0,0(r3)
+err2; std r6,8(r3)
+err2; std r8,16(r3)
+err2; std r9,24(r3)
+err2; std r10,32(r3)
+err2; std r11,40(r3)
+err2; std r12,48(r3)
+err2; std r14,56(r3)
+err2; std r15,64(r3)
+err2; std r16,72(r3)
+err2; std r17,80(r3)
+err2; std r18,88(r3)
+err2; std r19,96(r3)
+err2; std r20,104(r3)
+err2; std r21,112(r3)
+err2; std r22,120(r3)
+ addi r3,r3,128
+ subi r7,r7,128
+ bdnz 4b
+
+ clrldi r5,r5,(64-7)
+
+ /* Up to 127B to go */
+5: srdi r6,r5,4
+ mtocrf 0x01,r6
+
+6: bf cr7*4+1,7f
+err2; ld r0,0(r4)
+err2; ld r6,8(r4)
+err2; ld r8,16(r4)
+err2; ld r9,24(r4)
+err2; ld r10,32(r4)
+err2; ld r11,40(r4)
+err2; ld r12,48(r4)
+err2; ld r14,56(r4)
+ addi r4,r4,64
+err2; std r0,0(r3)
+err2; std r6,8(r3)
+err2; std r8,16(r3)
+err2; std r9,24(r3)
+err2; std r10,32(r3)
+err2; std r11,40(r3)
+err2; std r12,48(r3)
+err2; std r14,56(r3)
+ addi r3,r3,64
+ subi r7,r7,64
+
+7: ld r14,STK_REG(R14)(r1)
+ ld r15,STK_REG(R15)(r1)
+ ld r16,STK_REG(R16)(r1)
+ ld r17,STK_REG(R17)(r1)
+ ld r18,STK_REG(R18)(r1)
+ ld r19,STK_REG(R19)(r1)
+ ld r20,STK_REG(R20)(r1)
+ ld r21,STK_REG(R21)(r1)
+ ld r22,STK_REG(R22)(r1)
+ addi r1,r1,STACKFRAMESIZE
+
+ /* Up to 63B to go */
+ bf cr7*4+2,8f
+err1; ld r0,0(r4)
+err1; ld r6,8(r4)
+err1; ld r8,16(r4)
+err1; ld r9,24(r4)
+ addi r4,r4,32
+err1; std r0,0(r3)
+err1; std r6,8(r3)
+err1; std r8,16(r3)
+err1; std r9,24(r3)
+ addi r3,r3,32
+ subi r7,r7,32
+
+ /* Up to 31B to go */
+8: bf cr7*4+3,9f
+err1; ld r0,0(r4)
+err1; ld r6,8(r4)
+ addi r4,r4,16
+err1; std r0,0(r3)
+err1; std r6,8(r3)
+ addi r3,r3,16
+ subi r7,r7,16
+
+9: clrldi r5,r5,(64-4)
+
+ /* Up to 15B to go */
+.Lshort_copy:
+ mtocrf 0x01,r5
+ bf cr7*4+0,12f
+err1; lwz r0,0(r4) /* Less chance of a reject with word ops */
+err1; lwz r6,4(r4)
+ addi r4,r4,8
+err1; stw r0,0(r3)
+err1; stw r6,4(r3)
+ addi r3,r3,8
+ subi r7,r7,8
+
+12: bf cr7*4+1,13f
+err1; lwz r0,0(r4)
+ addi r4,r4,4
+err1; stw r0,0(r3)
+ addi r3,r3,4
+ subi r7,r7,4
+
+13: bf cr7*4+2,14f
+err1; lhz r0,0(r4)
+ addi r4,r4,2
+err1; sth r0,0(r3)
+ addi r3,r3,2
+ subi r7,r7,2
+
+14: bf cr7*4+3,15f
+err1; lbz r0,0(r4)
+err1; stb r0,0(r3)
+
+15: li r3,0
+ blr
+
+EXPORT_SYMBOL_GPL(memcpy_mcsafe);
--
2.21.0
next prev parent reply other threads:[~2019-08-20 8:14 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-20 8:13 [PATCH v11 0/7] powerpc: implement machine check safe memcpy Santosh Sivaraj
2019-08-20 8:13 ` [PATCH v11 1/7] powerpc/mce: Schedule work from irq_work Santosh Sivaraj
2019-08-22 13:09 ` Michael Ellerman
2019-08-20 8:13 ` [PATCH v11 2/7] powerpc/mce: Fix MCE handling for huge pages Santosh Sivaraj
2019-08-20 8:13 ` [PATCH v11 3/7] powerpc/mce: Make machine_check_ue_event() static Santosh Sivaraj
2019-08-20 8:13 ` [PATCH v11 4/7] extable: Add function to search only kernel exception table Santosh Sivaraj
2019-08-20 8:13 ` [PATCH v11 5/7] powerpc/mce: Handle UE event for memcpy_mcsafe Santosh Sivaraj
2019-08-20 8:13 ` Santosh Sivaraj [this message]
2019-08-20 8:13 ` [PATCH v11 7/7] powerpc: add machine check safe copy_to_user Santosh Sivaraj
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190820081352.8641-7-santosh@fossix.org \
--to=santosh@fossix.org \
--cc=aneesh.kumar@linux.ibm.com \
--cc=arbab@linux.ibm.com \
--cc=bsingharora@gmail.com \
--cc=chandan@linux.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mahesh@linux.ibm.com \
--cc=mpe@ellerman.id.au \
--cc=npiggin@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).