linux_dsm_epyc7002/arch/sparc/lib/NG4memcpy.S

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 21:07:57 +07:00
/* SPDX-License-Identifier: GPL-2.0 */
/* NG4memcpy.S: Niagara-4 optimized memcpy.
*
* Copyright (C) 2012 David S. Miller (davem@davemloft.net)
*/
#ifdef __KERNEL__
#include <linux/linkage.h>
#include <asm/visasm.h>
#include <asm/asi.h>
#define GLOBAL_SPARE %g7
#else
#define ASI_BLK_INIT_QUAD_LDD_P 0xe2
#define FPRS_FEF 0x04
/* On T4 it is very expensive to access ASRs like %fprs and
* %asi, avoiding a read or a write can save ~50 cycles.
*/
#define FPU_ENTER \
rd %fprs, %o5; \
andcc %o5, FPRS_FEF, %g0; \
be,a,pn %icc, 999f; \
wr %g0, FPRS_FEF, %fprs; \
999:
#ifdef MEMCPY_DEBUG
#define VISEntryHalf FPU_ENTER; \
clr %g1; clr %g2; clr %g3; clr %g5; subcc %g0, %g0, %g0;
#define VISExitHalf and %o5, FPRS_FEF, %o5; wr %o5, 0x0, %fprs
#else
#define VISEntryHalf FPU_ENTER
#define VISExitHalf and %o5, FPRS_FEF, %o5; wr %o5, 0x0, %fprs
#endif
#define GLOBAL_SPARE %g5
#endif
#ifndef STORE_ASI
#ifndef SIMULATE_NIAGARA_ON_NON_NIAGARA
#define STORE_ASI ASI_BLK_INIT_QUAD_LDD_P
#else
#define STORE_ASI 0x80 /* ASI_P */
#endif
#endif
sparc64: Fix FPU register corruption with AES crypto offload. The AES loops in arch/sparc/crypto/aes_glue.c use a scheme where the key material is preloaded into the FPU registers, and then we loop over and over doing the crypt operation, reusing those pre-cooked key registers. There are intervening blkcipher*() calls between the crypt operation calls. And those might perform memcpy() and thus also try to use the FPU. The sparc64 kernel FPU usage mechanism is designed to allow such recursive uses, but with a catch. There has to be a trap between the two FPU using threads of control. The mechanism works by, when the FPU is already in use by the kernel, allocating a slot for FPU saving at trap time. Then if, within the trap handler, we try to use the FPU registers, the pre-trap FPU register state is saved into the slot. Then at trap return time we notice this and restore the pre-trap FPU state. Over the long term there are various more involved ways we can make this work, but for a quick fix let's take advantage of the fact that the situation where this happens is very limited. All sparc64 chips that support the crypto instructiosn also are using the Niagara4 memcpy routine, and that routine only uses the FPU for large copies where we can't get the source aligned properly to a multiple of 8 bytes. We look to see if the FPU is already in use in this context, and if so we use the non-large copy path which only uses integer registers. Furthermore, we also limit this special logic to when we are doing kernel copy, rather than a user copy. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-15 09:37:58 +07:00
#if !defined(EX_LD) && !defined(EX_ST)
#define NON_USER_COPY
#endif
#ifndef EX_LD
#define EX_LD(x,y) x
#endif
sparc64: fix FP corruption in user copy functions Short story: Exception handlers used by some copy_to_user() and copy_from_user() functions do not diligently clean up floating point register usage, and this can result in a user process seeing invalid values in floating point registers. This sometimes makes the process fail. Long story: Several cpu-specific (NG4, NG2, U1, U3) memcpy functions use floating point registers and VIS alignaddr/faligndata to accelerate data copying when source and dest addresses don't align well. Linux uses a lazy scheme for saving floating point registers; It is not done upon entering the kernel since it's a very expensive operation. Rather, it is done only when needed. If the kernel ends up not using FP regs during the course of some trap or system call, then it can return to user space without saving or restoring them. The various memcpy functions begin their FP code with VISEntry (or a variation thereof), which saves the FP regs. They conclude their FP code with VISExit (or a variation) which essentially marks the FP regs "clean", ie, they contain no unsaved values. fprs.FPRS_FEF is turned off so that a lazy restore will be triggered when/if the user process accesses floating point regs again. The bug is that the user copy variants of memcpy, copy_from_user() and copy_to_user(), employ an exception handling mechanism to detect faults when accessing user space addresses, and when this handler is invoked, an immediate return from the function is forced, and VISExit is not executed, thus leaving the fprs register in an indeterminate state, but often with fprs.FPRS_FEF set and one or more dirty bits. This results in a return to user space with invalid values in the FP regs, and since fprs.FPRS_FEF is on, no lazy restore occurs. This bug affects copy_to_user() and copy_from_user() for NG4, NG2, U3, and U1. All are fixed by using a new exception handler for those loads and stores that are done during the time between VISEnter and VISExit. n.b. In NG4memcpy, the problematic code can be triggered by a copy size greater than 128 bytes and an unaligned source address. This bug is known to be the cause of random user process memory corruptions while perf is running with the callgraph option (ie, perf record -g). This occurs because perf uses copy_from_user() to read user stacks, and may fault when it follows a stack frame pointer off to an invalid page. Validation checks on the stack address just obscure the underlying problem. Signed-off-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-23 13:24:49 +07:00
#ifndef EX_LD_FP
#define EX_LD_FP(x,y) x
sparc64: fix FP corruption in user copy functions Short story: Exception handlers used by some copy_to_user() and copy_from_user() functions do not diligently clean up floating point register usage, and this can result in a user process seeing invalid values in floating point registers. This sometimes makes the process fail. Long story: Several cpu-specific (NG4, NG2, U1, U3) memcpy functions use floating point registers and VIS alignaddr/faligndata to accelerate data copying when source and dest addresses don't align well. Linux uses a lazy scheme for saving floating point registers; It is not done upon entering the kernel since it's a very expensive operation. Rather, it is done only when needed. If the kernel ends up not using FP regs during the course of some trap or system call, then it can return to user space without saving or restoring them. The various memcpy functions begin their FP code with VISEntry (or a variation thereof), which saves the FP regs. They conclude their FP code with VISExit (or a variation) which essentially marks the FP regs "clean", ie, they contain no unsaved values. fprs.FPRS_FEF is turned off so that a lazy restore will be triggered when/if the user process accesses floating point regs again. The bug is that the user copy variants of memcpy, copy_from_user() and copy_to_user(), employ an exception handling mechanism to detect faults when accessing user space addresses, and when this handler is invoked, an immediate return from the function is forced, and VISExit is not executed, thus leaving the fprs register in an indeterminate state, but often with fprs.FPRS_FEF set and one or more dirty bits. This results in a return to user space with invalid values in the FP regs, and since fprs.FPRS_FEF is on, no lazy restore occurs. This bug affects copy_to_user() and copy_from_user() for NG4, NG2, U3, and U1. All are fixed by using a new exception handler for those loads and stores that are done during the time between VISEnter and VISExit. n.b. In NG4memcpy, the problematic code can be triggered by a copy size greater than 128 bytes and an unaligned source address. This bug is known to be the cause of random user process memory corruptions while perf is running with the callgraph option (ie, perf record -g). This occurs because perf uses copy_from_user() to read user stacks, and may fault when it follows a stack frame pointer off to an invalid page. Validation checks on the stack address just obscure the underlying problem. Signed-off-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-23 13:24:49 +07:00
#endif
#ifndef EX_ST
#define EX_ST(x,y) x
#endif
sparc64: fix FP corruption in user copy functions Short story: Exception handlers used by some copy_to_user() and copy_from_user() functions do not diligently clean up floating point register usage, and this can result in a user process seeing invalid values in floating point registers. This sometimes makes the process fail. Long story: Several cpu-specific (NG4, NG2, U1, U3) memcpy functions use floating point registers and VIS alignaddr/faligndata to accelerate data copying when source and dest addresses don't align well. Linux uses a lazy scheme for saving floating point registers; It is not done upon entering the kernel since it's a very expensive operation. Rather, it is done only when needed. If the kernel ends up not using FP regs during the course of some trap or system call, then it can return to user space without saving or restoring them. The various memcpy functions begin their FP code with VISEntry (or a variation thereof), which saves the FP regs. They conclude their FP code with VISExit (or a variation) which essentially marks the FP regs "clean", ie, they contain no unsaved values. fprs.FPRS_FEF is turned off so that a lazy restore will be triggered when/if the user process accesses floating point regs again. The bug is that the user copy variants of memcpy, copy_from_user() and copy_to_user(), employ an exception handling mechanism to detect faults when accessing user space addresses, and when this handler is invoked, an immediate return from the function is forced, and VISExit is not executed, thus leaving the fprs register in an indeterminate state, but often with fprs.FPRS_FEF set and one or more dirty bits. This results in a return to user space with invalid values in the FP regs, and since fprs.FPRS_FEF is on, no lazy restore occurs. This bug affects copy_to_user() and copy_from_user() for NG4, NG2, U3, and U1. All are fixed by using a new exception handler for those loads and stores that are done during the time between VISEnter and VISExit. n.b. In NG4memcpy, the problematic code can be triggered by a copy size greater than 128 bytes and an unaligned source address. This bug is known to be the cause of random user process memory corruptions while perf is running with the callgraph option (ie, perf record -g). This occurs because perf uses copy_from_user() to read user stacks, and may fault when it follows a stack frame pointer off to an invalid page. Validation checks on the stack address just obscure the underlying problem. Signed-off-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-23 13:24:49 +07:00
#ifndef EX_ST_FP
#define EX_ST_FP(x,y) x
sparc64: fix FP corruption in user copy functions Short story: Exception handlers used by some copy_to_user() and copy_from_user() functions do not diligently clean up floating point register usage, and this can result in a user process seeing invalid values in floating point registers. This sometimes makes the process fail. Long story: Several cpu-specific (NG4, NG2, U1, U3) memcpy functions use floating point registers and VIS alignaddr/faligndata to accelerate data copying when source and dest addresses don't align well. Linux uses a lazy scheme for saving floating point registers; It is not done upon entering the kernel since it's a very expensive operation. Rather, it is done only when needed. If the kernel ends up not using FP regs during the course of some trap or system call, then it can return to user space without saving or restoring them. The various memcpy functions begin their FP code with VISEntry (or a variation thereof), which saves the FP regs. They conclude their FP code with VISExit (or a variation) which essentially marks the FP regs "clean", ie, they contain no unsaved values. fprs.FPRS_FEF is turned off so that a lazy restore will be triggered when/if the user process accesses floating point regs again. The bug is that the user copy variants of memcpy, copy_from_user() and copy_to_user(), employ an exception handling mechanism to detect faults when accessing user space addresses, and when this handler is invoked, an immediate return from the function is forced, and VISExit is not executed, thus leaving the fprs register in an indeterminate state, but often with fprs.FPRS_FEF set and one or more dirty bits. This results in a return to user space with invalid values in the FP regs, and since fprs.FPRS_FEF is on, no lazy restore occurs. This bug affects copy_to_user() and copy_from_user() for NG4, NG2, U3, and U1. All are fixed by using a new exception handler for those loads and stores that are done during the time between VISEnter and VISExit. n.b. In NG4memcpy, the problematic code can be triggered by a copy size greater than 128 bytes and an unaligned source address. This bug is known to be the cause of random user process memory corruptions while perf is running with the callgraph option (ie, perf record -g). This occurs because perf uses copy_from_user() to read user stacks, and may fault when it follows a stack frame pointer off to an invalid page. Validation checks on the stack address just obscure the underlying problem. Signed-off-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-23 13:24:49 +07:00
#endif
#ifndef LOAD
#define LOAD(type,addr,dest) type [addr], dest
#endif
#ifndef STORE
#ifndef MEMCPY_DEBUG
#define STORE(type,src,addr) type src, [addr]
#else
#define STORE(type,src,addr) type##a src, [addr] %asi
#endif
#endif
#ifndef STORE_INIT
#define STORE_INIT(src,addr) stxa src, [addr] STORE_ASI
#endif
#ifndef FUNC_NAME
#define FUNC_NAME NG4memcpy
#endif
#ifndef PREAMBLE
#define PREAMBLE
#endif
#ifndef XCC
#define XCC xcc
#endif
.register %g2,#scratch
.register %g3,#scratch
.text
#ifndef EX_RETVAL
#define EX_RETVAL(x) x
#endif
.align 64
.globl FUNC_NAME
.type FUNC_NAME,#function
FUNC_NAME: /* %o0=dst, %o1=src, %o2=len */
#ifdef MEMCPY_DEBUG
wr %g0, 0x80, %asi
#endif
srlx %o2, 31, %g2
cmp %g2, 0
tne %XCC, 5
PREAMBLE
mov %o0, %o3
brz,pn %o2, .Lexit
cmp %o2, 3
ble,pn %icc, .Ltiny
cmp %o2, 19
ble,pn %icc, .Lsmall
or %o0, %o1, %g2
cmp %o2, 128
bl,pn %icc, .Lmedium
nop
.Llarge:/* len >= 0x80 */
/* First get dest 8 byte aligned. */
sub %g0, %o0, %g1
and %g1, 0x7, %g1
brz,pt %g1, 51f
sub %o2, %g1, %o2
1: EX_LD(LOAD(ldub, %o1 + 0x00, %g2), memcpy_retl_o2_plus_g1)
add %o1, 1, %o1
subcc %g1, 1, %g1
add %o0, 1, %o0
bne,pt %icc, 1b
EX_ST(STORE(stb, %g2, %o0 - 0x01), memcpy_retl_o2_plus_g1_plus_1)
51: LOAD(prefetch, %o1 + 0x040, #n_reads_strong)
LOAD(prefetch, %o1 + 0x080, #n_reads_strong)
LOAD(prefetch, %o1 + 0x0c0, #n_reads_strong)
LOAD(prefetch, %o1 + 0x100, #n_reads_strong)
LOAD(prefetch, %o1 + 0x140, #n_reads_strong)
LOAD(prefetch, %o1 + 0x180, #n_reads_strong)
LOAD(prefetch, %o1 + 0x1c0, #n_reads_strong)
LOAD(prefetch, %o1 + 0x200, #n_reads_strong)
/* Check if we can use the straight fully aligned
* loop, or we require the alignaddr/faligndata variant.
*/
andcc %o1, 0x7, %o5
bne,pn %icc, .Llarge_src_unaligned
sub %g0, %o0, %g1
/* Legitimize the use of initializing stores by getting dest
* to be 64-byte aligned.
*/
and %g1, 0x3f, %g1
brz,pt %g1, .Llarge_aligned
sub %o2, %g1, %o2
1: EX_LD(LOAD(ldx, %o1 + 0x00, %g2), memcpy_retl_o2_plus_g1)
add %o1, 8, %o1
subcc %g1, 8, %g1
add %o0, 8, %o0
bne,pt %icc, 1b
EX_ST(STORE(stx, %g2, %o0 - 0x08), memcpy_retl_o2_plus_g1_plus_8)
.Llarge_aligned:
/* len >= 0x80 && src 8-byte aligned && dest 8-byte aligned */
andn %o2, 0x3f, %o4
sub %o2, %o4, %o2
1: EX_LD(LOAD(ldx, %o1 + 0x00, %g1), memcpy_retl_o2_plus_o4)
add %o1, 0x40, %o1
EX_LD(LOAD(ldx, %o1 - 0x38, %g2), memcpy_retl_o2_plus_o4)
subcc %o4, 0x40, %o4
EX_LD(LOAD(ldx, %o1 - 0x30, %g3), memcpy_retl_o2_plus_o4_plus_64)
EX_LD(LOAD(ldx, %o1 - 0x28, GLOBAL_SPARE), memcpy_retl_o2_plus_o4_plus_64)
EX_LD(LOAD(ldx, %o1 - 0x20, %o5), memcpy_retl_o2_plus_o4_plus_64)
EX_ST(STORE_INIT(%g1, %o0), memcpy_retl_o2_plus_o4_plus_64)
add %o0, 0x08, %o0
EX_ST(STORE_INIT(%g2, %o0), memcpy_retl_o2_plus_o4_plus_56)
add %o0, 0x08, %o0
EX_LD(LOAD(ldx, %o1 - 0x18, %g2), memcpy_retl_o2_plus_o4_plus_48)
EX_ST(STORE_INIT(%g3, %o0), memcpy_retl_o2_plus_o4_plus_48)
add %o0, 0x08, %o0
EX_LD(LOAD(ldx, %o1 - 0x10, %g3), memcpy_retl_o2_plus_o4_plus_40)
EX_ST(STORE_INIT(GLOBAL_SPARE, %o0), memcpy_retl_o2_plus_o4_plus_40)
add %o0, 0x08, %o0
EX_LD(LOAD(ldx, %o1 - 0x08, GLOBAL_SPARE), memcpy_retl_o2_plus_o4_plus_32)
EX_ST(STORE_INIT(%o5, %o0), memcpy_retl_o2_plus_o4_plus_32)
add %o0, 0x08, %o0
EX_ST(STORE_INIT(%g2, %o0), memcpy_retl_o2_plus_o4_plus_24)
add %o0, 0x08, %o0
EX_ST(STORE_INIT(%g3, %o0), memcpy_retl_o2_plus_o4_plus_16)
add %o0, 0x08, %o0
EX_ST(STORE_INIT(GLOBAL_SPARE, %o0), memcpy_retl_o2_plus_o4_plus_8)
add %o0, 0x08, %o0
bne,pt %icc, 1b
LOAD(prefetch, %o1 + 0x200, #n_reads_strong)
membar #StoreLoad | #StoreStore
brz,pn %o2, .Lexit
cmp %o2, 19
ble,pn %icc, .Lsmall_unaligned
nop
ba,a,pt %icc, .Lmedium_noprefetch
.Lexit: retl
mov EX_RETVAL(%o3), %o0
.Llarge_src_unaligned:
sparc64: Fix FPU register corruption with AES crypto offload. The AES loops in arch/sparc/crypto/aes_glue.c use a scheme where the key material is preloaded into the FPU registers, and then we loop over and over doing the crypt operation, reusing those pre-cooked key registers. There are intervening blkcipher*() calls between the crypt operation calls. And those might perform memcpy() and thus also try to use the FPU. The sparc64 kernel FPU usage mechanism is designed to allow such recursive uses, but with a catch. There has to be a trap between the two FPU using threads of control. The mechanism works by, when the FPU is already in use by the kernel, allocating a slot for FPU saving at trap time. Then if, within the trap handler, we try to use the FPU registers, the pre-trap FPU register state is saved into the slot. Then at trap return time we notice this and restore the pre-trap FPU state. Over the long term there are various more involved ways we can make this work, but for a quick fix let's take advantage of the fact that the situation where this happens is very limited. All sparc64 chips that support the crypto instructiosn also are using the Niagara4 memcpy routine, and that routine only uses the FPU for large copies where we can't get the source aligned properly to a multiple of 8 bytes. We look to see if the FPU is already in use in this context, and if so we use the non-large copy path which only uses integer registers. Furthermore, we also limit this special logic to when we are doing kernel copy, rather than a user copy. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-15 09:37:58 +07:00
#ifdef NON_USER_COPY
VISEntryHalfFast(.Lmedium_vis_entry_fail)
#else
VISEntryHalf
#endif
andn %o2, 0x3f, %o4
sub %o2, %o4, %o2
alignaddr %o1, %g0, %g1
add %o1, %o4, %o1
EX_LD_FP(LOAD(ldd, %g1 + 0x00, %f0), memcpy_retl_o2_plus_o4)
1: EX_LD_FP(LOAD(ldd, %g1 + 0x08, %f2), memcpy_retl_o2_plus_o4)
subcc %o4, 0x40, %o4
EX_LD_FP(LOAD(ldd, %g1 + 0x10, %f4), memcpy_retl_o2_plus_o4_plus_64)
EX_LD_FP(LOAD(ldd, %g1 + 0x18, %f6), memcpy_retl_o2_plus_o4_plus_64)
EX_LD_FP(LOAD(ldd, %g1 + 0x20, %f8), memcpy_retl_o2_plus_o4_plus_64)
EX_LD_FP(LOAD(ldd, %g1 + 0x28, %f10), memcpy_retl_o2_plus_o4_plus_64)
EX_LD_FP(LOAD(ldd, %g1 + 0x30, %f12), memcpy_retl_o2_plus_o4_plus_64)
EX_LD_FP(LOAD(ldd, %g1 + 0x38, %f14), memcpy_retl_o2_plus_o4_plus_64)
faligndata %f0, %f2, %f16
EX_LD_FP(LOAD(ldd, %g1 + 0x40, %f0), memcpy_retl_o2_plus_o4_plus_64)
faligndata %f2, %f4, %f18
add %g1, 0x40, %g1
faligndata %f4, %f6, %f20
faligndata %f6, %f8, %f22
faligndata %f8, %f10, %f24
faligndata %f10, %f12, %f26
faligndata %f12, %f14, %f28
faligndata %f14, %f0, %f30
EX_ST_FP(STORE(std, %f16, %o0 + 0x00), memcpy_retl_o2_plus_o4_plus_64)
EX_ST_FP(STORE(std, %f18, %o0 + 0x08), memcpy_retl_o2_plus_o4_plus_56)
EX_ST_FP(STORE(std, %f20, %o0 + 0x10), memcpy_retl_o2_plus_o4_plus_48)
EX_ST_FP(STORE(std, %f22, %o0 + 0x18), memcpy_retl_o2_plus_o4_plus_40)
EX_ST_FP(STORE(std, %f24, %o0 + 0x20), memcpy_retl_o2_plus_o4_plus_32)
EX_ST_FP(STORE(std, %f26, %o0 + 0x28), memcpy_retl_o2_plus_o4_plus_24)
EX_ST_FP(STORE(std, %f28, %o0 + 0x30), memcpy_retl_o2_plus_o4_plus_16)
EX_ST_FP(STORE(std, %f30, %o0 + 0x38), memcpy_retl_o2_plus_o4_plus_8)
add %o0, 0x40, %o0
bne,pt %icc, 1b
LOAD(prefetch, %g1 + 0x200, #n_reads_strong)
#ifdef NON_USER_COPY
VISExitHalfFast
#else
VISExitHalf
#endif
brz,pn %o2, .Lexit
cmp %o2, 19
ble,pn %icc, .Lsmall_unaligned
nop
ba,a,pt %icc, .Lmedium_unaligned
sparc64: Fix FPU register corruption with AES crypto offload. The AES loops in arch/sparc/crypto/aes_glue.c use a scheme where the key material is preloaded into the FPU registers, and then we loop over and over doing the crypt operation, reusing those pre-cooked key registers. There are intervening blkcipher*() calls between the crypt operation calls. And those might perform memcpy() and thus also try to use the FPU. The sparc64 kernel FPU usage mechanism is designed to allow such recursive uses, but with a catch. There has to be a trap between the two FPU using threads of control. The mechanism works by, when the FPU is already in use by the kernel, allocating a slot for FPU saving at trap time. Then if, within the trap handler, we try to use the FPU registers, the pre-trap FPU register state is saved into the slot. Then at trap return time we notice this and restore the pre-trap FPU state. Over the long term there are various more involved ways we can make this work, but for a quick fix let's take advantage of the fact that the situation where this happens is very limited. All sparc64 chips that support the crypto instructiosn also are using the Niagara4 memcpy routine, and that routine only uses the FPU for large copies where we can't get the source aligned properly to a multiple of 8 bytes. We look to see if the FPU is already in use in this context, and if so we use the non-large copy path which only uses integer registers. Furthermore, we also limit this special logic to when we are doing kernel copy, rather than a user copy. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-15 09:37:58 +07:00
#ifdef NON_USER_COPY
.Lmedium_vis_entry_fail:
or %o0, %o1, %g2
#endif
.Lmedium:
LOAD(prefetch, %o1 + 0x40, #n_reads_strong)
andcc %g2, 0x7, %g0
bne,pn %icc, .Lmedium_unaligned
nop
.Lmedium_noprefetch:
andncc %o2, 0x20 - 1, %o5
be,pn %icc, 2f
sub %o2, %o5, %o2
1: EX_LD(LOAD(ldx, %o1 + 0x00, %g1), memcpy_retl_o2_plus_o5)
EX_LD(LOAD(ldx, %o1 + 0x08, %g2), memcpy_retl_o2_plus_o5)
EX_LD(LOAD(ldx, %o1 + 0x10, GLOBAL_SPARE), memcpy_retl_o2_plus_o5)
EX_LD(LOAD(ldx, %o1 + 0x18, %o4), memcpy_retl_o2_plus_o5)
add %o1, 0x20, %o1
subcc %o5, 0x20, %o5
EX_ST(STORE(stx, %g1, %o0 + 0x00), memcpy_retl_o2_plus_o5_plus_32)
EX_ST(STORE(stx, %g2, %o0 + 0x08), memcpy_retl_o2_plus_o5_plus_24)
EX_ST(STORE(stx, GLOBAL_SPARE, %o0 + 0x10), memcpy_retl_o2_plus_o5_plus_24)
EX_ST(STORE(stx, %o4, %o0 + 0x18), memcpy_retl_o2_plus_o5_plus_8)
bne,pt %icc, 1b
add %o0, 0x20, %o0
2: andcc %o2, 0x18, %o5
be,pt %icc, 3f
sub %o2, %o5, %o2
1: EX_LD(LOAD(ldx, %o1 + 0x00, %g1), memcpy_retl_o2_plus_o5)
add %o1, 0x08, %o1
add %o0, 0x08, %o0
subcc %o5, 0x08, %o5
bne,pt %icc, 1b
EX_ST(STORE(stx, %g1, %o0 - 0x08), memcpy_retl_o2_plus_o5_plus_8)
3: brz,pt %o2, .Lexit
cmp %o2, 0x04
bl,pn %icc, .Ltiny
nop
EX_LD(LOAD(lduw, %o1 + 0x00, %g1), memcpy_retl_o2)
add %o1, 0x04, %o1
add %o0, 0x04, %o0
subcc %o2, 0x04, %o2
bne,pn %icc, .Ltiny
EX_ST(STORE(stw, %g1, %o0 - 0x04), memcpy_retl_o2_plus_4)
ba,a,pt %icc, .Lexit
.Lmedium_unaligned:
/* First get dest 8 byte aligned. */
sub %g0, %o0, %g1
and %g1, 0x7, %g1
brz,pt %g1, 2f
sub %o2, %g1, %o2
1: EX_LD(LOAD(ldub, %o1 + 0x00, %g2), memcpy_retl_o2_plus_g1)
add %o1, 1, %o1
subcc %g1, 1, %g1
add %o0, 1, %o0
bne,pt %icc, 1b
EX_ST(STORE(stb, %g2, %o0 - 0x01), memcpy_retl_o2_plus_g1_plus_1)
2:
and %o1, 0x7, %g1
brz,pn %g1, .Lmedium_noprefetch
sll %g1, 3, %g1
mov 64, %g2
sub %g2, %g1, %g2
andn %o1, 0x7, %o1
EX_LD(LOAD(ldx, %o1 + 0x00, %o4), memcpy_retl_o2)
sllx %o4, %g1, %o4
andn %o2, 0x08 - 1, %o5
sub %o2, %o5, %o2
1: EX_LD(LOAD(ldx, %o1 + 0x08, %g3), memcpy_retl_o2_plus_o5)
add %o1, 0x08, %o1
subcc %o5, 0x08, %o5
srlx %g3, %g2, GLOBAL_SPARE
or GLOBAL_SPARE, %o4, GLOBAL_SPARE
EX_ST(STORE(stx, GLOBAL_SPARE, %o0 + 0x00), memcpy_retl_o2_plus_o5_plus_8)
add %o0, 0x08, %o0
bne,pt %icc, 1b
sllx %g3, %g1, %o4
srl %g1, 3, %g1
add %o1, %g1, %o1
brz,pn %o2, .Lexit
nop
ba,pt %icc, .Lsmall_unaligned
.Ltiny:
EX_LD(LOAD(ldub, %o1 + 0x00, %g1), memcpy_retl_o2)
subcc %o2, 1, %o2
be,pn %icc, .Lexit
EX_ST(STORE(stb, %g1, %o0 + 0x00), memcpy_retl_o2_plus_1)
EX_LD(LOAD(ldub, %o1 + 0x01, %g1), memcpy_retl_o2)
subcc %o2, 1, %o2
be,pn %icc, .Lexit
EX_ST(STORE(stb, %g1, %o0 + 0x01), memcpy_retl_o2_plus_1)
EX_LD(LOAD(ldub, %o1 + 0x02, %g1), memcpy_retl_o2)
ba,pt %icc, .Lexit
EX_ST(STORE(stb, %g1, %o0 + 0x02), memcpy_retl_o2)
.Lsmall:
andcc %g2, 0x3, %g0
bne,pn %icc, .Lsmall_unaligned
andn %o2, 0x4 - 1, %o5
sub %o2, %o5, %o2
1:
EX_LD(LOAD(lduw, %o1 + 0x00, %g1), memcpy_retl_o2_plus_o5)
add %o1, 0x04, %o1
subcc %o5, 0x04, %o5
add %o0, 0x04, %o0
bne,pt %icc, 1b
EX_ST(STORE(stw, %g1, %o0 - 0x04), memcpy_retl_o2_plus_o5_plus_4)
brz,pt %o2, .Lexit
nop
ba,a,pt %icc, .Ltiny
.Lsmall_unaligned:
1: EX_LD(LOAD(ldub, %o1 + 0x00, %g1), memcpy_retl_o2)
add %o1, 1, %o1
add %o0, 1, %o0
subcc %o2, 1, %o2
bne,pt %icc, 1b
EX_ST(STORE(stb, %g1, %o0 - 0x01), memcpy_retl_o2_plus_1)
ba,a,pt %icc, .Lexit
arch/sparc: Avoid DCTI Couples Avoid un-intended DCTI Couples. Use of DCTI couples is deprecated. Also address the "Programming Note" for optimal performance. Here is the complete text from Oracle SPARC Architecture Specs. 6.3.4.7 DCTI Couples "A delayed control transfer instruction (DCTI) in the delay slot of another DCTI is referred to as a “DCTI couple”. The use of DCTI couples is deprecated in the Oracle SPARC Architecture; no new software should place a DCTI in the delay slot of another DCTI, because on future Oracle SPARC Architecture implementations DCTI couples may execute either slowly or differently than the programmer assumes it will. SPARC V8 and SPARC V9 Compatibility Note The SPARC V8 architecture left behavior undefined for a DCTI couple. The SPARC V9 architecture defined behavior in that case, but as of UltraSPARC Architecture 2005, use of DCTI couples was deprecated. Software should not expect high performance from DCTI couples, and performance of DCTI couples should be expected to decline further in future processors. Programming Note As noted in TABLE 6-5 on page 115, an annulled branch-always (branch-always with a = 1) instruction is not architecturally a DCTI. However, since not all implementations make that distinction, for optimal performance, a DCTI should not be placed in the instruction word immediately following an annulled branch-always instruction (BA,A or BPA,A)." Signed-off-by: Babu Moger <babu.moger@oracle.com> Reviewed-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-18 03:52:21 +07:00
nop
.size FUNC_NAME, .-FUNC_NAME