1659 lines
41 KiB
C
1659 lines
41 KiB
C
/*
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* Handle unaligned accesses by emulation.
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 1996, 1998, 1999, 2002 by Ralf Baechle
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* Copyright (C) 1999 Silicon Graphics, Inc.
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*
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* This file contains exception handler for address error exception with the
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* special capability to execute faulting instructions in software. The
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* handler does not try to handle the case when the program counter points
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* to an address not aligned to a word boundary.
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*
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* Putting data to unaligned addresses is a bad practice even on Intel where
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* only the performance is affected. Much worse is that such code is non-
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* portable. Due to several programs that die on MIPS due to alignment
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* problems I decided to implement this handler anyway though I originally
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* didn't intend to do this at all for user code.
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*
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* For now I enable fixing of address errors by default to make life easier.
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* I however intend to disable this somewhen in the future when the alignment
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* problems with user programs have been fixed. For programmers this is the
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* right way to go.
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*
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* Fixing address errors is a per process option. The option is inherited
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* across fork(2) and execve(2) calls. If you really want to use the
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* option in your user programs - I discourage the use of the software
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* emulation strongly - use the following code in your userland stuff:
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*
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* #include <sys/sysmips.h>
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*
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* ...
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* sysmips(MIPS_FIXADE, x);
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* ...
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*
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* The argument x is 0 for disabling software emulation, enabled otherwise.
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*
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* Below a little program to play around with this feature.
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*
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* #include <stdio.h>
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* #include <sys/sysmips.h>
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*
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* struct foo {
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* unsigned char bar[8];
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* };
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*
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* main(int argc, char *argv[])
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* {
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* struct foo x = {0, 1, 2, 3, 4, 5, 6, 7};
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* unsigned int *p = (unsigned int *) (x.bar + 3);
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* int i;
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*
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* if (argc > 1)
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* sysmips(MIPS_FIXADE, atoi(argv[1]));
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*
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* printf("*p = %08lx\n", *p);
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*
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* *p = 0xdeadface;
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*
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* for(i = 0; i <= 7; i++)
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* printf("%02x ", x.bar[i]);
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* printf("\n");
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* }
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*
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* Coprocessor loads are not supported; I think this case is unimportant
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* in the practice.
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*
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* TODO: Handle ndc (attempted store to doubleword in uncached memory)
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* exception for the R6000.
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* A store crossing a page boundary might be executed only partially.
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* Undo the partial store in this case.
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*/
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#include <linux/context_tracking.h>
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#include <linux/mm.h>
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#include <linux/signal.h>
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#include <linux/smp.h>
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#include <linux/sched.h>
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#include <linux/debugfs.h>
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#include <linux/perf_event.h>
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#include <asm/asm.h>
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#include <asm/branch.h>
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#include <asm/byteorder.h>
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#include <asm/cop2.h>
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#include <asm/fpu.h>
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#include <asm/fpu_emulator.h>
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#include <asm/inst.h>
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#include <asm/uaccess.h>
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#include <asm/fpu.h>
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#include <asm/fpu_emulator.h>
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#define STR(x) __STR(x)
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#define __STR(x) #x
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enum {
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UNALIGNED_ACTION_QUIET,
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UNALIGNED_ACTION_SIGNAL,
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UNALIGNED_ACTION_SHOW,
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};
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#ifdef CONFIG_DEBUG_FS
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static u32 unaligned_instructions;
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static u32 unaligned_action;
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#else
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#define unaligned_action UNALIGNED_ACTION_QUIET
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#endif
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extern void show_registers(struct pt_regs *regs);
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#ifdef __BIG_ENDIAN
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#define LoadHW(addr, value, res) \
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__asm__ __volatile__ (".set\tnoat\n" \
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"1:\tlb\t%0, 0(%2)\n" \
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"2:\tlbu\t$1, 1(%2)\n\t" \
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"sll\t%0, 0x8\n\t" \
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"or\t%0, $1\n\t" \
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"li\t%1, 0\n" \
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"3:\t.set\tat\n\t" \
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|
".insn\n\t" \
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".section\t.fixup,\"ax\"\n\t" \
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"4:\tli\t%1, %3\n\t" \
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"j\t3b\n\t" \
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|
".previous\n\t" \
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|
".section\t__ex_table,\"a\"\n\t" \
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STR(PTR)"\t1b, 4b\n\t" \
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STR(PTR)"\t2b, 4b\n\t" \
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|
".previous" \
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: "=&r" (value), "=r" (res) \
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: "r" (addr), "i" (-EFAULT));
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#define LoadW(addr, value, res) \
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__asm__ __volatile__ ( \
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"1:\tlwl\t%0, (%2)\n" \
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"2:\tlwr\t%0, 3(%2)\n\t" \
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"li\t%1, 0\n" \
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|
"3:\n\t" \
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|
".insn\n\t" \
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|
".section\t.fixup,\"ax\"\n\t" \
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"4:\tli\t%1, %3\n\t" \
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|
"j\t3b\n\t" \
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|
".previous\n\t" \
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|
".section\t__ex_table,\"a\"\n\t" \
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STR(PTR)"\t1b, 4b\n\t" \
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STR(PTR)"\t2b, 4b\n\t" \
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".previous" \
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: "=&r" (value), "=r" (res) \
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: "r" (addr), "i" (-EFAULT));
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#define LoadHWU(addr, value, res) \
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__asm__ __volatile__ ( \
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".set\tnoat\n" \
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"1:\tlbu\t%0, 0(%2)\n" \
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"2:\tlbu\t$1, 1(%2)\n\t" \
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"sll\t%0, 0x8\n\t" \
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"or\t%0, $1\n\t" \
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"li\t%1, 0\n" \
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"3:\n\t" \
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".insn\n\t" \
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|
".set\tat\n\t" \
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".section\t.fixup,\"ax\"\n\t" \
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"4:\tli\t%1, %3\n\t" \
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"j\t3b\n\t" \
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".previous\n\t" \
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".section\t__ex_table,\"a\"\n\t" \
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STR(PTR)"\t1b, 4b\n\t" \
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STR(PTR)"\t2b, 4b\n\t" \
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".previous" \
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: "=&r" (value), "=r" (res) \
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: "r" (addr), "i" (-EFAULT));
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#define LoadWU(addr, value, res) \
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__asm__ __volatile__ ( \
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"1:\tlwl\t%0, (%2)\n" \
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"2:\tlwr\t%0, 3(%2)\n\t" \
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"dsll\t%0, %0, 32\n\t" \
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"dsrl\t%0, %0, 32\n\t" \
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"li\t%1, 0\n" \
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"3:\n\t" \
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|
".insn\n\t" \
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|
"\t.section\t.fixup,\"ax\"\n\t" \
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"4:\tli\t%1, %3\n\t" \
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|
"j\t3b\n\t" \
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|
".previous\n\t" \
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|
".section\t__ex_table,\"a\"\n\t" \
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STR(PTR)"\t1b, 4b\n\t" \
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STR(PTR)"\t2b, 4b\n\t" \
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|
".previous" \
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: "=&r" (value), "=r" (res) \
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: "r" (addr), "i" (-EFAULT));
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#define LoadDW(addr, value, res) \
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__asm__ __volatile__ ( \
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"1:\tldl\t%0, (%2)\n" \
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"2:\tldr\t%0, 7(%2)\n\t" \
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"li\t%1, 0\n" \
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"3:\n\t" \
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|
".insn\n\t" \
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|
"\t.section\t.fixup,\"ax\"\n\t" \
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"4:\tli\t%1, %3\n\t" \
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|
"j\t3b\n\t" \
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|
".previous\n\t" \
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".section\t__ex_table,\"a\"\n\t" \
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STR(PTR)"\t1b, 4b\n\t" \
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STR(PTR)"\t2b, 4b\n\t" \
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".previous" \
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: "=&r" (value), "=r" (res) \
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: "r" (addr), "i" (-EFAULT));
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|
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#define StoreHW(addr, value, res) \
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__asm__ __volatile__ ( \
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".set\tnoat\n" \
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"1:\tsb\t%1, 1(%2)\n\t" \
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"srl\t$1, %1, 0x8\n" \
|
|
"2:\tsb\t$1, 0(%2)\n\t" \
|
|
".set\tat\n\t" \
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|
"li\t%0, 0\n" \
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|
"3:\n\t" \
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|
".insn\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%0, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
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STR(PTR)"\t1b, 4b\n\t" \
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STR(PTR)"\t2b, 4b\n\t" \
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|
".previous" \
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: "=r" (res) \
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: "r" (value), "r" (addr), "i" (-EFAULT));
|
|
|
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#define StoreW(addr, value, res) \
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__asm__ __volatile__ ( \
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"1:\tswl\t%1,(%2)\n" \
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"2:\tswr\t%1, 3(%2)\n\t" \
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"li\t%0, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%0, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
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|
STR(PTR)"\t1b, 4b\n\t" \
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|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
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: "=r" (res) \
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: "r" (value), "r" (addr), "i" (-EFAULT));
|
|
|
|
#define StoreDW(addr, value, res) \
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__asm__ __volatile__ ( \
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"1:\tsdl\t%1,(%2)\n" \
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"2:\tsdr\t%1, 7(%2)\n\t" \
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|
"li\t%0, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%0, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
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|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=r" (res) \
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|
: "r" (value), "r" (addr), "i" (-EFAULT));
|
|
#endif
|
|
|
|
#ifdef __LITTLE_ENDIAN
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|
#define LoadHW(addr, value, res) \
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__asm__ __volatile__ (".set\tnoat\n" \
|
|
"1:\tlb\t%0, 1(%2)\n" \
|
|
"2:\tlbu\t$1, 0(%2)\n\t" \
|
|
"sll\t%0, 0x8\n\t" \
|
|
"or\t%0, $1\n\t" \
|
|
"li\t%1, 0\n" \
|
|
"3:\t.set\tat\n\t" \
|
|
".insn\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%1, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
|
|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=&r" (value), "=r" (res) \
|
|
: "r" (addr), "i" (-EFAULT));
|
|
|
|
#define LoadW(addr, value, res) \
|
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__asm__ __volatile__ ( \
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|
"1:\tlwl\t%0, 3(%2)\n" \
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"2:\tlwr\t%0, (%2)\n\t" \
|
|
"li\t%1, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%1, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
|
|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=&r" (value), "=r" (res) \
|
|
: "r" (addr), "i" (-EFAULT));
|
|
|
|
#define LoadHWU(addr, value, res) \
|
|
__asm__ __volatile__ ( \
|
|
".set\tnoat\n" \
|
|
"1:\tlbu\t%0, 1(%2)\n" \
|
|
"2:\tlbu\t$1, 0(%2)\n\t" \
|
|
"sll\t%0, 0x8\n\t" \
|
|
"or\t%0, $1\n\t" \
|
|
"li\t%1, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
".set\tat\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%1, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
|
|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=&r" (value), "=r" (res) \
|
|
: "r" (addr), "i" (-EFAULT));
|
|
|
|
#define LoadWU(addr, value, res) \
|
|
__asm__ __volatile__ ( \
|
|
"1:\tlwl\t%0, 3(%2)\n" \
|
|
"2:\tlwr\t%0, (%2)\n\t" \
|
|
"dsll\t%0, %0, 32\n\t" \
|
|
"dsrl\t%0, %0, 32\n\t" \
|
|
"li\t%1, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
"\t.section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%1, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
|
|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=&r" (value), "=r" (res) \
|
|
: "r" (addr), "i" (-EFAULT));
|
|
|
|
#define LoadDW(addr, value, res) \
|
|
__asm__ __volatile__ ( \
|
|
"1:\tldl\t%0, 7(%2)\n" \
|
|
"2:\tldr\t%0, (%2)\n\t" \
|
|
"li\t%1, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
"\t.section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%1, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
|
|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=&r" (value), "=r" (res) \
|
|
: "r" (addr), "i" (-EFAULT));
|
|
|
|
#define StoreHW(addr, value, res) \
|
|
__asm__ __volatile__ ( \
|
|
".set\tnoat\n" \
|
|
"1:\tsb\t%1, 0(%2)\n\t" \
|
|
"srl\t$1,%1, 0x8\n" \
|
|
"2:\tsb\t$1, 1(%2)\n\t" \
|
|
".set\tat\n\t" \
|
|
"li\t%0, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%0, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
|
|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=r" (res) \
|
|
: "r" (value), "r" (addr), "i" (-EFAULT));
|
|
|
|
#define StoreW(addr, value, res) \
|
|
__asm__ __volatile__ ( \
|
|
"1:\tswl\t%1, 3(%2)\n" \
|
|
"2:\tswr\t%1, (%2)\n\t" \
|
|
"li\t%0, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%0, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
|
|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=r" (res) \
|
|
: "r" (value), "r" (addr), "i" (-EFAULT));
|
|
|
|
#define StoreDW(addr, value, res) \
|
|
__asm__ __volatile__ ( \
|
|
"1:\tsdl\t%1, 7(%2)\n" \
|
|
"2:\tsdr\t%1, (%2)\n\t" \
|
|
"li\t%0, 0\n" \
|
|
"3:\n\t" \
|
|
".insn\n\t" \
|
|
".section\t.fixup,\"ax\"\n\t" \
|
|
"4:\tli\t%0, %3\n\t" \
|
|
"j\t3b\n\t" \
|
|
".previous\n\t" \
|
|
".section\t__ex_table,\"a\"\n\t" \
|
|
STR(PTR)"\t1b, 4b\n\t" \
|
|
STR(PTR)"\t2b, 4b\n\t" \
|
|
".previous" \
|
|
: "=r" (res) \
|
|
: "r" (value), "r" (addr), "i" (-EFAULT));
|
|
#endif
|
|
|
|
static void emulate_load_store_insn(struct pt_regs *regs,
|
|
void __user *addr, unsigned int __user *pc)
|
|
{
|
|
union mips_instruction insn;
|
|
unsigned long value;
|
|
unsigned int res;
|
|
unsigned long origpc;
|
|
unsigned long orig31;
|
|
void __user *fault_addr = NULL;
|
|
|
|
origpc = (unsigned long)pc;
|
|
orig31 = regs->regs[31];
|
|
|
|
perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
|
|
|
|
/*
|
|
* This load never faults.
|
|
*/
|
|
__get_user(insn.word, pc);
|
|
|
|
switch (insn.i_format.opcode) {
|
|
/*
|
|
* These are instructions that a compiler doesn't generate. We
|
|
* can assume therefore that the code is MIPS-aware and
|
|
* really buggy. Emulating these instructions would break the
|
|
* semantics anyway.
|
|
*/
|
|
case ll_op:
|
|
case lld_op:
|
|
case sc_op:
|
|
case scd_op:
|
|
|
|
/*
|
|
* For these instructions the only way to create an address
|
|
* error is an attempted access to kernel/supervisor address
|
|
* space.
|
|
*/
|
|
case ldl_op:
|
|
case ldr_op:
|
|
case lwl_op:
|
|
case lwr_op:
|
|
case sdl_op:
|
|
case sdr_op:
|
|
case swl_op:
|
|
case swr_op:
|
|
case lb_op:
|
|
case lbu_op:
|
|
case sb_op:
|
|
goto sigbus;
|
|
|
|
/*
|
|
* The remaining opcodes are the ones that are really of
|
|
* interest.
|
|
*/
|
|
case lh_op:
|
|
if (!access_ok(VERIFY_READ, addr, 2))
|
|
goto sigbus;
|
|
|
|
LoadHW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
compute_return_epc(regs);
|
|
regs->regs[insn.i_format.rt] = value;
|
|
break;
|
|
|
|
case lw_op:
|
|
if (!access_ok(VERIFY_READ, addr, 4))
|
|
goto sigbus;
|
|
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
compute_return_epc(regs);
|
|
regs->regs[insn.i_format.rt] = value;
|
|
break;
|
|
|
|
case lhu_op:
|
|
if (!access_ok(VERIFY_READ, addr, 2))
|
|
goto sigbus;
|
|
|
|
LoadHWU(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
compute_return_epc(regs);
|
|
regs->regs[insn.i_format.rt] = value;
|
|
break;
|
|
|
|
case lwu_op:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_READ, addr, 4))
|
|
goto sigbus;
|
|
|
|
LoadWU(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
compute_return_epc(regs);
|
|
regs->regs[insn.i_format.rt] = value;
|
|
break;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
case ld_op:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_READ, addr, 8))
|
|
goto sigbus;
|
|
|
|
LoadDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
compute_return_epc(regs);
|
|
regs->regs[insn.i_format.rt] = value;
|
|
break;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
case sh_op:
|
|
if (!access_ok(VERIFY_WRITE, addr, 2))
|
|
goto sigbus;
|
|
|
|
compute_return_epc(regs);
|
|
value = regs->regs[insn.i_format.rt];
|
|
StoreHW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
break;
|
|
|
|
case sw_op:
|
|
if (!access_ok(VERIFY_WRITE, addr, 4))
|
|
goto sigbus;
|
|
|
|
compute_return_epc(regs);
|
|
value = regs->regs[insn.i_format.rt];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
break;
|
|
|
|
case sd_op:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_WRITE, addr, 8))
|
|
goto sigbus;
|
|
|
|
compute_return_epc(regs);
|
|
value = regs->regs[insn.i_format.rt];
|
|
StoreDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
break;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
case lwc1_op:
|
|
case ldc1_op:
|
|
case swc1_op:
|
|
case sdc1_op:
|
|
die_if_kernel("Unaligned FP access in kernel code", regs);
|
|
BUG_ON(!used_math());
|
|
BUG_ON(!is_fpu_owner());
|
|
|
|
lose_fpu(1); /* Save FPU state for the emulator. */
|
|
res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
|
|
&fault_addr);
|
|
own_fpu(1); /* Restore FPU state. */
|
|
|
|
/* Signal if something went wrong. */
|
|
process_fpemu_return(res, fault_addr);
|
|
|
|
if (res == 0)
|
|
break;
|
|
return;
|
|
|
|
/*
|
|
* COP2 is available to implementor for application specific use.
|
|
* It's up to applications to register a notifier chain and do
|
|
* whatever they have to do, including possible sending of signals.
|
|
*/
|
|
case lwc2_op:
|
|
cu2_notifier_call_chain(CU2_LWC2_OP, regs);
|
|
break;
|
|
|
|
case ldc2_op:
|
|
cu2_notifier_call_chain(CU2_LDC2_OP, regs);
|
|
break;
|
|
|
|
case swc2_op:
|
|
cu2_notifier_call_chain(CU2_SWC2_OP, regs);
|
|
break;
|
|
|
|
case sdc2_op:
|
|
cu2_notifier_call_chain(CU2_SDC2_OP, regs);
|
|
break;
|
|
|
|
default:
|
|
/*
|
|
* Pheeee... We encountered an yet unknown instruction or
|
|
* cache coherence problem. Die sucker, die ...
|
|
*/
|
|
goto sigill;
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
unaligned_instructions++;
|
|
#endif
|
|
|
|
return;
|
|
|
|
fault:
|
|
/* roll back jump/branch */
|
|
regs->cp0_epc = origpc;
|
|
regs->regs[31] = orig31;
|
|
/* Did we have an exception handler installed? */
|
|
if (fixup_exception(regs))
|
|
return;
|
|
|
|
die_if_kernel("Unhandled kernel unaligned access", regs);
|
|
force_sig(SIGSEGV, current);
|
|
|
|
return;
|
|
|
|
sigbus:
|
|
die_if_kernel("Unhandled kernel unaligned access", regs);
|
|
force_sig(SIGBUS, current);
|
|
|
|
return;
|
|
|
|
sigill:
|
|
die_if_kernel
|
|
("Unhandled kernel unaligned access or invalid instruction", regs);
|
|
force_sig(SIGILL, current);
|
|
}
|
|
|
|
/* Recode table from 16-bit register notation to 32-bit GPR. */
|
|
const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 };
|
|
|
|
/* Recode table from 16-bit STORE register notation to 32-bit GPR. */
|
|
const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 };
|
|
|
|
static void emulate_load_store_microMIPS(struct pt_regs *regs,
|
|
void __user *addr)
|
|
{
|
|
unsigned long value;
|
|
unsigned int res;
|
|
int i;
|
|
unsigned int reg = 0, rvar;
|
|
unsigned long orig31;
|
|
u16 __user *pc16;
|
|
u16 halfword;
|
|
unsigned int word;
|
|
unsigned long origpc, contpc;
|
|
union mips_instruction insn;
|
|
struct mm_decoded_insn mminsn;
|
|
void __user *fault_addr = NULL;
|
|
|
|
origpc = regs->cp0_epc;
|
|
orig31 = regs->regs[31];
|
|
|
|
mminsn.micro_mips_mode = 1;
|
|
|
|
/*
|
|
* This load never faults.
|
|
*/
|
|
pc16 = (unsigned short __user *)msk_isa16_mode(regs->cp0_epc);
|
|
__get_user(halfword, pc16);
|
|
pc16++;
|
|
contpc = regs->cp0_epc + 2;
|
|
word = ((unsigned int)halfword << 16);
|
|
mminsn.pc_inc = 2;
|
|
|
|
if (!mm_insn_16bit(halfword)) {
|
|
__get_user(halfword, pc16);
|
|
pc16++;
|
|
contpc = regs->cp0_epc + 4;
|
|
mminsn.pc_inc = 4;
|
|
word |= halfword;
|
|
}
|
|
mminsn.insn = word;
|
|
|
|
if (get_user(halfword, pc16))
|
|
goto fault;
|
|
mminsn.next_pc_inc = 2;
|
|
word = ((unsigned int)halfword << 16);
|
|
|
|
if (!mm_insn_16bit(halfword)) {
|
|
pc16++;
|
|
if (get_user(halfword, pc16))
|
|
goto fault;
|
|
mminsn.next_pc_inc = 4;
|
|
word |= halfword;
|
|
}
|
|
mminsn.next_insn = word;
|
|
|
|
insn = (union mips_instruction)(mminsn.insn);
|
|
if (mm_isBranchInstr(regs, mminsn, &contpc))
|
|
insn = (union mips_instruction)(mminsn.next_insn);
|
|
|
|
/* Parse instruction to find what to do */
|
|
|
|
switch (insn.mm_i_format.opcode) {
|
|
|
|
case mm_pool32a_op:
|
|
switch (insn.mm_x_format.func) {
|
|
case mm_lwxs_op:
|
|
reg = insn.mm_x_format.rd;
|
|
goto loadW;
|
|
}
|
|
|
|
goto sigbus;
|
|
|
|
case mm_pool32b_op:
|
|
switch (insn.mm_m_format.func) {
|
|
case mm_lwp_func:
|
|
reg = insn.mm_m_format.rd;
|
|
if (reg == 31)
|
|
goto sigbus;
|
|
|
|
if (!access_ok(VERIFY_READ, addr, 8))
|
|
goto sigbus;
|
|
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg] = value;
|
|
addr += 4;
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg + 1] = value;
|
|
goto success;
|
|
|
|
case mm_swp_func:
|
|
reg = insn.mm_m_format.rd;
|
|
if (reg == 31)
|
|
goto sigbus;
|
|
|
|
if (!access_ok(VERIFY_WRITE, addr, 8))
|
|
goto sigbus;
|
|
|
|
value = regs->regs[reg];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 4;
|
|
value = regs->regs[reg + 1];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
goto success;
|
|
|
|
case mm_ldp_func:
|
|
#ifdef CONFIG_64BIT
|
|
reg = insn.mm_m_format.rd;
|
|
if (reg == 31)
|
|
goto sigbus;
|
|
|
|
if (!access_ok(VERIFY_READ, addr, 16))
|
|
goto sigbus;
|
|
|
|
LoadDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg] = value;
|
|
addr += 8;
|
|
LoadDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg + 1] = value;
|
|
goto success;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
goto sigill;
|
|
|
|
case mm_sdp_func:
|
|
#ifdef CONFIG_64BIT
|
|
reg = insn.mm_m_format.rd;
|
|
if (reg == 31)
|
|
goto sigbus;
|
|
|
|
if (!access_ok(VERIFY_WRITE, addr, 16))
|
|
goto sigbus;
|
|
|
|
value = regs->regs[reg];
|
|
StoreDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 8;
|
|
value = regs->regs[reg + 1];
|
|
StoreDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
goto success;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
goto sigill;
|
|
|
|
case mm_lwm32_func:
|
|
reg = insn.mm_m_format.rd;
|
|
rvar = reg & 0xf;
|
|
if ((rvar > 9) || !reg)
|
|
goto sigill;
|
|
if (reg & 0x10) {
|
|
if (!access_ok
|
|
(VERIFY_READ, addr, 4 * (rvar + 1)))
|
|
goto sigbus;
|
|
} else {
|
|
if (!access_ok(VERIFY_READ, addr, 4 * rvar))
|
|
goto sigbus;
|
|
}
|
|
if (rvar == 9)
|
|
rvar = 8;
|
|
for (i = 16; rvar; rvar--, i++) {
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 4;
|
|
regs->regs[i] = value;
|
|
}
|
|
if ((reg & 0xf) == 9) {
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 4;
|
|
regs->regs[30] = value;
|
|
}
|
|
if (reg & 0x10) {
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[31] = value;
|
|
}
|
|
goto success;
|
|
|
|
case mm_swm32_func:
|
|
reg = insn.mm_m_format.rd;
|
|
rvar = reg & 0xf;
|
|
if ((rvar > 9) || !reg)
|
|
goto sigill;
|
|
if (reg & 0x10) {
|
|
if (!access_ok
|
|
(VERIFY_WRITE, addr, 4 * (rvar + 1)))
|
|
goto sigbus;
|
|
} else {
|
|
if (!access_ok(VERIFY_WRITE, addr, 4 * rvar))
|
|
goto sigbus;
|
|
}
|
|
if (rvar == 9)
|
|
rvar = 8;
|
|
for (i = 16; rvar; rvar--, i++) {
|
|
value = regs->regs[i];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 4;
|
|
}
|
|
if ((reg & 0xf) == 9) {
|
|
value = regs->regs[30];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 4;
|
|
}
|
|
if (reg & 0x10) {
|
|
value = regs->regs[31];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
}
|
|
goto success;
|
|
|
|
case mm_ldm_func:
|
|
#ifdef CONFIG_64BIT
|
|
reg = insn.mm_m_format.rd;
|
|
rvar = reg & 0xf;
|
|
if ((rvar > 9) || !reg)
|
|
goto sigill;
|
|
if (reg & 0x10) {
|
|
if (!access_ok
|
|
(VERIFY_READ, addr, 8 * (rvar + 1)))
|
|
goto sigbus;
|
|
} else {
|
|
if (!access_ok(VERIFY_READ, addr, 8 * rvar))
|
|
goto sigbus;
|
|
}
|
|
if (rvar == 9)
|
|
rvar = 8;
|
|
|
|
for (i = 16; rvar; rvar--, i++) {
|
|
LoadDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 4;
|
|
regs->regs[i] = value;
|
|
}
|
|
if ((reg & 0xf) == 9) {
|
|
LoadDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 8;
|
|
regs->regs[30] = value;
|
|
}
|
|
if (reg & 0x10) {
|
|
LoadDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[31] = value;
|
|
}
|
|
goto success;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
goto sigill;
|
|
|
|
case mm_sdm_func:
|
|
#ifdef CONFIG_64BIT
|
|
reg = insn.mm_m_format.rd;
|
|
rvar = reg & 0xf;
|
|
if ((rvar > 9) || !reg)
|
|
goto sigill;
|
|
if (reg & 0x10) {
|
|
if (!access_ok
|
|
(VERIFY_WRITE, addr, 8 * (rvar + 1)))
|
|
goto sigbus;
|
|
} else {
|
|
if (!access_ok(VERIFY_WRITE, addr, 8 * rvar))
|
|
goto sigbus;
|
|
}
|
|
if (rvar == 9)
|
|
rvar = 8;
|
|
|
|
for (i = 16; rvar; rvar--, i++) {
|
|
value = regs->regs[i];
|
|
StoreDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 8;
|
|
}
|
|
if ((reg & 0xf) == 9) {
|
|
value = regs->regs[30];
|
|
StoreDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 8;
|
|
}
|
|
if (reg & 0x10) {
|
|
value = regs->regs[31];
|
|
StoreDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
}
|
|
goto success;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
goto sigill;
|
|
|
|
/* LWC2, SWC2, LDC2, SDC2 are not serviced */
|
|
}
|
|
|
|
goto sigbus;
|
|
|
|
case mm_pool32c_op:
|
|
switch (insn.mm_m_format.func) {
|
|
case mm_lwu_func:
|
|
reg = insn.mm_m_format.rd;
|
|
goto loadWU;
|
|
}
|
|
|
|
/* LL,SC,LLD,SCD are not serviced */
|
|
goto sigbus;
|
|
|
|
case mm_pool32f_op:
|
|
switch (insn.mm_x_format.func) {
|
|
case mm_lwxc1_func:
|
|
case mm_swxc1_func:
|
|
case mm_ldxc1_func:
|
|
case mm_sdxc1_func:
|
|
goto fpu_emul;
|
|
}
|
|
|
|
goto sigbus;
|
|
|
|
case mm_ldc132_op:
|
|
case mm_sdc132_op:
|
|
case mm_lwc132_op:
|
|
case mm_swc132_op:
|
|
fpu_emul:
|
|
/* roll back jump/branch */
|
|
regs->cp0_epc = origpc;
|
|
regs->regs[31] = orig31;
|
|
|
|
die_if_kernel("Unaligned FP access in kernel code", regs);
|
|
BUG_ON(!used_math());
|
|
BUG_ON(!is_fpu_owner());
|
|
|
|
lose_fpu(1); /* save the FPU state for the emulator */
|
|
res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
|
|
&fault_addr);
|
|
own_fpu(1); /* restore FPU state */
|
|
|
|
/* If something went wrong, signal */
|
|
process_fpemu_return(res, fault_addr);
|
|
|
|
if (res == 0)
|
|
goto success;
|
|
return;
|
|
|
|
case mm_lh32_op:
|
|
reg = insn.mm_i_format.rt;
|
|
goto loadHW;
|
|
|
|
case mm_lhu32_op:
|
|
reg = insn.mm_i_format.rt;
|
|
goto loadHWU;
|
|
|
|
case mm_lw32_op:
|
|
reg = insn.mm_i_format.rt;
|
|
goto loadW;
|
|
|
|
case mm_sh32_op:
|
|
reg = insn.mm_i_format.rt;
|
|
goto storeHW;
|
|
|
|
case mm_sw32_op:
|
|
reg = insn.mm_i_format.rt;
|
|
goto storeW;
|
|
|
|
case mm_ld32_op:
|
|
reg = insn.mm_i_format.rt;
|
|
goto loadDW;
|
|
|
|
case mm_sd32_op:
|
|
reg = insn.mm_i_format.rt;
|
|
goto storeDW;
|
|
|
|
case mm_pool16c_op:
|
|
switch (insn.mm16_m_format.func) {
|
|
case mm_lwm16_op:
|
|
reg = insn.mm16_m_format.rlist;
|
|
rvar = reg + 1;
|
|
if (!access_ok(VERIFY_READ, addr, 4 * rvar))
|
|
goto sigbus;
|
|
|
|
for (i = 16; rvar; rvar--, i++) {
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 4;
|
|
regs->regs[i] = value;
|
|
}
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[31] = value;
|
|
|
|
goto success;
|
|
|
|
case mm_swm16_op:
|
|
reg = insn.mm16_m_format.rlist;
|
|
rvar = reg + 1;
|
|
if (!access_ok(VERIFY_WRITE, addr, 4 * rvar))
|
|
goto sigbus;
|
|
|
|
for (i = 16; rvar; rvar--, i++) {
|
|
value = regs->regs[i];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
addr += 4;
|
|
}
|
|
value = regs->regs[31];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
|
|
goto success;
|
|
|
|
}
|
|
|
|
goto sigbus;
|
|
|
|
case mm_lhu16_op:
|
|
reg = reg16to32[insn.mm16_rb_format.rt];
|
|
goto loadHWU;
|
|
|
|
case mm_lw16_op:
|
|
reg = reg16to32[insn.mm16_rb_format.rt];
|
|
goto loadW;
|
|
|
|
case mm_sh16_op:
|
|
reg = reg16to32st[insn.mm16_rb_format.rt];
|
|
goto storeHW;
|
|
|
|
case mm_sw16_op:
|
|
reg = reg16to32st[insn.mm16_rb_format.rt];
|
|
goto storeW;
|
|
|
|
case mm_lwsp16_op:
|
|
reg = insn.mm16_r5_format.rt;
|
|
goto loadW;
|
|
|
|
case mm_swsp16_op:
|
|
reg = insn.mm16_r5_format.rt;
|
|
goto storeW;
|
|
|
|
case mm_lwgp16_op:
|
|
reg = reg16to32[insn.mm16_r3_format.rt];
|
|
goto loadW;
|
|
|
|
default:
|
|
goto sigill;
|
|
}
|
|
|
|
loadHW:
|
|
if (!access_ok(VERIFY_READ, addr, 2))
|
|
goto sigbus;
|
|
|
|
LoadHW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg] = value;
|
|
goto success;
|
|
|
|
loadHWU:
|
|
if (!access_ok(VERIFY_READ, addr, 2))
|
|
goto sigbus;
|
|
|
|
LoadHWU(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg] = value;
|
|
goto success;
|
|
|
|
loadW:
|
|
if (!access_ok(VERIFY_READ, addr, 4))
|
|
goto sigbus;
|
|
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg] = value;
|
|
goto success;
|
|
|
|
loadWU:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_READ, addr, 4))
|
|
goto sigbus;
|
|
|
|
LoadWU(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg] = value;
|
|
goto success;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
loadDW:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_READ, addr, 8))
|
|
goto sigbus;
|
|
|
|
LoadDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
regs->regs[reg] = value;
|
|
goto success;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
storeHW:
|
|
if (!access_ok(VERIFY_WRITE, addr, 2))
|
|
goto sigbus;
|
|
|
|
value = regs->regs[reg];
|
|
StoreHW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
goto success;
|
|
|
|
storeW:
|
|
if (!access_ok(VERIFY_WRITE, addr, 4))
|
|
goto sigbus;
|
|
|
|
value = regs->regs[reg];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
goto success;
|
|
|
|
storeDW:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_WRITE, addr, 8))
|
|
goto sigbus;
|
|
|
|
value = regs->regs[reg];
|
|
StoreDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
goto success;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
success:
|
|
regs->cp0_epc = contpc; /* advance or branch */
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
unaligned_instructions++;
|
|
#endif
|
|
return;
|
|
|
|
fault:
|
|
/* roll back jump/branch */
|
|
regs->cp0_epc = origpc;
|
|
regs->regs[31] = orig31;
|
|
/* Did we have an exception handler installed? */
|
|
if (fixup_exception(regs))
|
|
return;
|
|
|
|
die_if_kernel("Unhandled kernel unaligned access", regs);
|
|
force_sig(SIGSEGV, current);
|
|
|
|
return;
|
|
|
|
sigbus:
|
|
die_if_kernel("Unhandled kernel unaligned access", regs);
|
|
force_sig(SIGBUS, current);
|
|
|
|
return;
|
|
|
|
sigill:
|
|
die_if_kernel
|
|
("Unhandled kernel unaligned access or invalid instruction", regs);
|
|
force_sig(SIGILL, current);
|
|
}
|
|
|
|
static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
|
|
{
|
|
unsigned long value;
|
|
unsigned int res;
|
|
int reg;
|
|
unsigned long orig31;
|
|
u16 __user *pc16;
|
|
unsigned long origpc;
|
|
union mips16e_instruction mips16inst, oldinst;
|
|
|
|
origpc = regs->cp0_epc;
|
|
orig31 = regs->regs[31];
|
|
pc16 = (unsigned short __user *)msk_isa16_mode(origpc);
|
|
/*
|
|
* This load never faults.
|
|
*/
|
|
__get_user(mips16inst.full, pc16);
|
|
oldinst = mips16inst;
|
|
|
|
/* skip EXTEND instruction */
|
|
if (mips16inst.ri.opcode == MIPS16e_extend_op) {
|
|
pc16++;
|
|
__get_user(mips16inst.full, pc16);
|
|
} else if (delay_slot(regs)) {
|
|
/* skip jump instructions */
|
|
/* JAL/JALX are 32 bits but have OPCODE in first short int */
|
|
if (mips16inst.ri.opcode == MIPS16e_jal_op)
|
|
pc16++;
|
|
pc16++;
|
|
if (get_user(mips16inst.full, pc16))
|
|
goto sigbus;
|
|
}
|
|
|
|
switch (mips16inst.ri.opcode) {
|
|
case MIPS16e_i64_op: /* I64 or RI64 instruction */
|
|
switch (mips16inst.i64.func) { /* I64/RI64 func field check */
|
|
case MIPS16e_ldpc_func:
|
|
case MIPS16e_ldsp_func:
|
|
reg = reg16to32[mips16inst.ri64.ry];
|
|
goto loadDW;
|
|
|
|
case MIPS16e_sdsp_func:
|
|
reg = reg16to32[mips16inst.ri64.ry];
|
|
goto writeDW;
|
|
|
|
case MIPS16e_sdrasp_func:
|
|
reg = 29; /* GPRSP */
|
|
goto writeDW;
|
|
}
|
|
|
|
goto sigbus;
|
|
|
|
case MIPS16e_swsp_op:
|
|
case MIPS16e_lwpc_op:
|
|
case MIPS16e_lwsp_op:
|
|
reg = reg16to32[mips16inst.ri.rx];
|
|
break;
|
|
|
|
case MIPS16e_i8_op:
|
|
if (mips16inst.i8.func != MIPS16e_swrasp_func)
|
|
goto sigbus;
|
|
reg = 29; /* GPRSP */
|
|
break;
|
|
|
|
default:
|
|
reg = reg16to32[mips16inst.rri.ry];
|
|
break;
|
|
}
|
|
|
|
switch (mips16inst.ri.opcode) {
|
|
|
|
case MIPS16e_lb_op:
|
|
case MIPS16e_lbu_op:
|
|
case MIPS16e_sb_op:
|
|
goto sigbus;
|
|
|
|
case MIPS16e_lh_op:
|
|
if (!access_ok(VERIFY_READ, addr, 2))
|
|
goto sigbus;
|
|
|
|
LoadHW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
MIPS16e_compute_return_epc(regs, &oldinst);
|
|
regs->regs[reg] = value;
|
|
break;
|
|
|
|
case MIPS16e_lhu_op:
|
|
if (!access_ok(VERIFY_READ, addr, 2))
|
|
goto sigbus;
|
|
|
|
LoadHWU(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
MIPS16e_compute_return_epc(regs, &oldinst);
|
|
regs->regs[reg] = value;
|
|
break;
|
|
|
|
case MIPS16e_lw_op:
|
|
case MIPS16e_lwpc_op:
|
|
case MIPS16e_lwsp_op:
|
|
if (!access_ok(VERIFY_READ, addr, 4))
|
|
goto sigbus;
|
|
|
|
LoadW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
MIPS16e_compute_return_epc(regs, &oldinst);
|
|
regs->regs[reg] = value;
|
|
break;
|
|
|
|
case MIPS16e_lwu_op:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_READ, addr, 4))
|
|
goto sigbus;
|
|
|
|
LoadWU(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
MIPS16e_compute_return_epc(regs, &oldinst);
|
|
regs->regs[reg] = value;
|
|
break;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
case MIPS16e_ld_op:
|
|
loadDW:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_READ, addr, 8))
|
|
goto sigbus;
|
|
|
|
LoadDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
MIPS16e_compute_return_epc(regs, &oldinst);
|
|
regs->regs[reg] = value;
|
|
break;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
case MIPS16e_sh_op:
|
|
if (!access_ok(VERIFY_WRITE, addr, 2))
|
|
goto sigbus;
|
|
|
|
MIPS16e_compute_return_epc(regs, &oldinst);
|
|
value = regs->regs[reg];
|
|
StoreHW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
break;
|
|
|
|
case MIPS16e_sw_op:
|
|
case MIPS16e_swsp_op:
|
|
case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */
|
|
if (!access_ok(VERIFY_WRITE, addr, 4))
|
|
goto sigbus;
|
|
|
|
MIPS16e_compute_return_epc(regs, &oldinst);
|
|
value = regs->regs[reg];
|
|
StoreW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
break;
|
|
|
|
case MIPS16e_sd_op:
|
|
writeDW:
|
|
#ifdef CONFIG_64BIT
|
|
/*
|
|
* A 32-bit kernel might be running on a 64-bit processor. But
|
|
* if we're on a 32-bit processor and an i-cache incoherency
|
|
* or race makes us see a 64-bit instruction here the sdl/sdr
|
|
* would blow up, so for now we don't handle unaligned 64-bit
|
|
* instructions on 32-bit kernels.
|
|
*/
|
|
if (!access_ok(VERIFY_WRITE, addr, 8))
|
|
goto sigbus;
|
|
|
|
MIPS16e_compute_return_epc(regs, &oldinst);
|
|
value = regs->regs[reg];
|
|
StoreDW(addr, value, res);
|
|
if (res)
|
|
goto fault;
|
|
break;
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/* Cannot handle 64-bit instructions in 32-bit kernel */
|
|
goto sigill;
|
|
|
|
default:
|
|
/*
|
|
* Pheeee... We encountered an yet unknown instruction or
|
|
* cache coherence problem. Die sucker, die ...
|
|
*/
|
|
goto sigill;
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
unaligned_instructions++;
|
|
#endif
|
|
|
|
return;
|
|
|
|
fault:
|
|
/* roll back jump/branch */
|
|
regs->cp0_epc = origpc;
|
|
regs->regs[31] = orig31;
|
|
/* Did we have an exception handler installed? */
|
|
if (fixup_exception(regs))
|
|
return;
|
|
|
|
die_if_kernel("Unhandled kernel unaligned access", regs);
|
|
force_sig(SIGSEGV, current);
|
|
|
|
return;
|
|
|
|
sigbus:
|
|
die_if_kernel("Unhandled kernel unaligned access", regs);
|
|
force_sig(SIGBUS, current);
|
|
|
|
return;
|
|
|
|
sigill:
|
|
die_if_kernel
|
|
("Unhandled kernel unaligned access or invalid instruction", regs);
|
|
force_sig(SIGILL, current);
|
|
}
|
|
|
|
asmlinkage void do_ade(struct pt_regs *regs)
|
|
{
|
|
enum ctx_state prev_state;
|
|
unsigned int __user *pc;
|
|
mm_segment_t seg;
|
|
|
|
prev_state = exception_enter();
|
|
perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS,
|
|
1, regs, regs->cp0_badvaddr);
|
|
/*
|
|
* Did we catch a fault trying to load an instruction?
|
|
*/
|
|
if (regs->cp0_badvaddr == regs->cp0_epc)
|
|
goto sigbus;
|
|
|
|
if (user_mode(regs) && !test_thread_flag(TIF_FIXADE))
|
|
goto sigbus;
|
|
if (unaligned_action == UNALIGNED_ACTION_SIGNAL)
|
|
goto sigbus;
|
|
|
|
/*
|
|
* Do branch emulation only if we didn't forward the exception.
|
|
* This is all so but ugly ...
|
|
*/
|
|
|
|
/*
|
|
* Are we running in microMIPS mode?
|
|
*/
|
|
if (get_isa16_mode(regs->cp0_epc)) {
|
|
/*
|
|
* Did we catch a fault trying to load an instruction in
|
|
* 16-bit mode?
|
|
*/
|
|
if (regs->cp0_badvaddr == msk_isa16_mode(regs->cp0_epc))
|
|
goto sigbus;
|
|
if (unaligned_action == UNALIGNED_ACTION_SHOW)
|
|
show_registers(regs);
|
|
|
|
if (cpu_has_mmips) {
|
|
seg = get_fs();
|
|
if (!user_mode(regs))
|
|
set_fs(KERNEL_DS);
|
|
emulate_load_store_microMIPS(regs,
|
|
(void __user *)regs->cp0_badvaddr);
|
|
set_fs(seg);
|
|
|
|
return;
|
|
}
|
|
|
|
if (cpu_has_mips16) {
|
|
seg = get_fs();
|
|
if (!user_mode(regs))
|
|
set_fs(KERNEL_DS);
|
|
emulate_load_store_MIPS16e(regs,
|
|
(void __user *)regs->cp0_badvaddr);
|
|
set_fs(seg);
|
|
|
|
return;
|
|
}
|
|
|
|
goto sigbus;
|
|
}
|
|
|
|
if (unaligned_action == UNALIGNED_ACTION_SHOW)
|
|
show_registers(regs);
|
|
pc = (unsigned int __user *)exception_epc(regs);
|
|
|
|
seg = get_fs();
|
|
if (!user_mode(regs))
|
|
set_fs(KERNEL_DS);
|
|
emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc);
|
|
set_fs(seg);
|
|
|
|
return;
|
|
|
|
sigbus:
|
|
die_if_kernel("Kernel unaligned instruction access", regs);
|
|
force_sig(SIGBUS, current);
|
|
|
|
/*
|
|
* XXX On return from the signal handler we should advance the epc
|
|
*/
|
|
exception_exit(prev_state);
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
extern struct dentry *mips_debugfs_dir;
|
|
static int __init debugfs_unaligned(void)
|
|
{
|
|
struct dentry *d;
|
|
|
|
if (!mips_debugfs_dir)
|
|
return -ENODEV;
|
|
d = debugfs_create_u32("unaligned_instructions", S_IRUGO,
|
|
mips_debugfs_dir, &unaligned_instructions);
|
|
if (!d)
|
|
return -ENOMEM;
|
|
d = debugfs_create_u32("unaligned_action", S_IRUGO | S_IWUSR,
|
|
mips_debugfs_dir, &unaligned_action);
|
|
if (!d)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
__initcall(debugfs_unaligned);
|
|
#endif
|