diff options
Diffstat (limited to 'arch/arc/kernel/unaligned.c')
| -rw-r--r-- | arch/arc/kernel/unaligned.c | 55 |
1 files changed, 36 insertions, 19 deletions
diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c index c0f832f595d3..3b2d8b1bd271 100644 --- a/arch/arc/kernel/unaligned.c +++ b/arch/arc/kernel/unaligned.c @@ -1,20 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2011-2012 Synopsys (www.synopsys.com) * - * 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. - * * vineetg : May 2011 * -Adapted (from .26 to .35) * -original contribution by Tim.yao@amlogic.com - * */ #include <linux/types.h> +#include <linux/perf_event.h> #include <linux/ptrace.h> #include <linux/uaccess.h> #include <asm/disasm.h> +#include "unaligned.h" + +#ifdef CONFIG_CPU_BIG_ENDIAN +#define BE 1 +#define FIRST_BYTE_16 "swap %1, %1\n swape %1, %1\n" +#define FIRST_BYTE_32 "swape %1, %1\n" +#else +#define BE 0 +#define FIRST_BYTE_16 +#define FIRST_BYTE_32 +#endif #define __get8_unaligned_check(val, addr, err) \ __asm__( \ @@ -23,7 +31,7 @@ " .section .fixup,\"ax\"\n" \ " .align 4\n" \ "3: mov %0, 1\n" \ - " b 2b\n" \ + " j 2b\n" \ " .previous\n" \ " .section __ex_table,\"a\"\n" \ " .align 4\n" \ @@ -36,9 +44,9 @@ do { \ unsigned int err = 0, v, a = addr; \ __get8_unaligned_check(v, a, err); \ - val = v ; \ + val = v << ((BE) ? 8 : 0); \ __get8_unaligned_check(v, a, err); \ - val |= v << 8; \ + val |= v << ((BE) ? 0 : 8); \ if (err) \ goto fault; \ } while (0) @@ -47,13 +55,13 @@ do { \ unsigned int err = 0, v, a = addr; \ __get8_unaligned_check(v, a, err); \ - val = v << 0; \ + val = v << ((BE) ? 24 : 0); \ __get8_unaligned_check(v, a, err); \ - val |= v << 8; \ + val |= v << ((BE) ? 16 : 8); \ __get8_unaligned_check(v, a, err); \ - val |= v << 16; \ + val |= v << ((BE) ? 8 : 16); \ __get8_unaligned_check(v, a, err); \ - val |= v << 24; \ + val |= v << ((BE) ? 0 : 24); \ if (err) \ goto fault; \ } while (0) @@ -63,6 +71,7 @@ unsigned int err = 0, v = val, a = addr;\ \ __asm__( \ + FIRST_BYTE_16 \ "1: stb.ab %1, [%2, 1]\n" \ " lsr %1, %1, 8\n" \ "2: stb %1, [%2]\n" \ @@ -70,7 +79,7 @@ " .section .fixup,\"ax\"\n" \ " .align 4\n" \ "4: mov %0, 1\n" \ - " b 3b\n" \ + " j 3b\n" \ " .previous\n" \ " .section __ex_table,\"a\"\n" \ " .align 4\n" \ @@ -87,8 +96,9 @@ #define put32_unaligned_check(val, addr) \ do { \ unsigned int err = 0, v = val, a = addr;\ - __asm__( \ \ + __asm__( \ + FIRST_BYTE_32 \ "1: stb.ab %1, [%2, 1]\n" \ " lsr %1, %1, 8\n" \ "2: stb.ab %1, [%2, 1]\n" \ @@ -100,7 +110,7 @@ " .section .fixup,\"ax\"\n" \ " .align 4\n" \ "6: mov %0, 1\n" \ - " b 5b\n" \ + " j 5b\n" \ " .previous\n" \ " .section __ex_table,\"a\"\n" \ " .align 4\n" \ @@ -190,7 +200,6 @@ int misaligned_fixup(unsigned long address, struct pt_regs *regs, struct callee_regs *cregs) { struct disasm_state state; - char buf[TASK_COMM_LEN]; /* handle user mode only and only if enabled by sysadmin */ if (!user_mode(regs) || !unaligned_enabled) @@ -202,11 +211,11 @@ int misaligned_fixup(unsigned long address, struct pt_regs *regs, " performance significantly\n. To enable further" " logging of such instances, please \n" " echo 0 > /proc/sys/kernel/ignore-unaligned-usertrap\n", - get_task_comm(buf, current), task_pid_nr(current)); + current->comm, task_pid_nr(current)); } else { /* Add rate limiting if it gets down to it */ pr_warn("%s(%d): unaligned access to/from 0x%lx by PC: 0x%lx\n", - get_task_comm(buf, current), task_pid_nr(current), + current->comm, task_pid_nr(current), address, regs->ret); } @@ -228,13 +237,21 @@ int misaligned_fixup(unsigned long address, struct pt_regs *regs, if (state.fault) goto fault; + /* clear any remnants of delay slot */ if (delay_mode(regs)) { - regs->ret = regs->bta; + regs->ret = regs->bta & ~1U; regs->status32 &= ~STATUS_DE_MASK; } else { regs->ret += state.instr_len; + + /* handle zero-overhead-loop */ + if ((regs->ret == regs->lp_end) && (regs->lp_count)) { + regs->ret = regs->lp_start; + regs->lp_count--; + } } + perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address); return 0; fault: |
