diff options
Diffstat (limited to 'arch/mn10300/kernel/kprobes.c')
-rw-r--r-- | arch/mn10300/kernel/kprobes.c | 656 |
1 files changed, 0 insertions, 656 deletions
diff --git a/arch/mn10300/kernel/kprobes.c b/arch/mn10300/kernel/kprobes.c deleted file mode 100644 index 0311a7f..0000000 --- a/arch/mn10300/kernel/kprobes.c +++ /dev/null @@ -1,656 +0,0 @@ -/* MN10300 Kernel probes implementation - * - * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved. - * Written by Mark Salter (msalter@redhat.com) - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public Licence as published by - * the Free Software Foundation; either version 2 of the Licence, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public Licence for more details. - * - * You should have received a copy of the GNU General Public Licence - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - */ -#include <linux/kprobes.h> -#include <linux/ptrace.h> -#include <linux/spinlock.h> -#include <linux/preempt.h> -#include <linux/kdebug.h> -#include <asm/cacheflush.h> - -struct kretprobe_blackpoint kretprobe_blacklist[] = { { NULL, NULL } }; -const int kretprobe_blacklist_size = ARRAY_SIZE(kretprobe_blacklist); - -/* kprobe_status settings */ -#define KPROBE_HIT_ACTIVE 0x00000001 -#define KPROBE_HIT_SS 0x00000002 - -static struct kprobe *cur_kprobe; -static unsigned long cur_kprobe_orig_pc; -static unsigned long cur_kprobe_next_pc; -static int cur_kprobe_ss_flags; -static unsigned long kprobe_status; -static kprobe_opcode_t cur_kprobe_ss_buf[MAX_INSN_SIZE + 2]; -static unsigned long cur_kprobe_bp_addr; - -DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL; - - -/* singlestep flag bits */ -#define SINGLESTEP_BRANCH 1 -#define SINGLESTEP_PCREL 2 - -#define READ_BYTE(p, valp) \ - do { *(u8 *)(valp) = *(u8 *)(p); } while (0) - -#define READ_WORD16(p, valp) \ - do { \ - READ_BYTE((p), (valp)); \ - READ_BYTE((u8 *)(p) + 1, (u8 *)(valp) + 1); \ - } while (0) - -#define READ_WORD32(p, valp) \ - do { \ - READ_BYTE((p), (valp)); \ - READ_BYTE((u8 *)(p) + 1, (u8 *)(valp) + 1); \ - READ_BYTE((u8 *)(p) + 2, (u8 *)(valp) + 2); \ - READ_BYTE((u8 *)(p) + 3, (u8 *)(valp) + 3); \ - } while (0) - - -static const u8 mn10300_insn_sizes[256] = -{ - /* 1 2 3 4 5 6 7 8 9 a b c d e f */ - 1, 3, 3, 3, 1, 3, 3, 3, 1, 3, 3, 3, 1, 3, 3, 3, /* 0 */ - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 1 */ - 2, 2, 2, 2, 3, 3, 3, 3, 2, 2, 2, 2, 3, 3, 3, 3, /* 2 */ - 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 1, 1, 1, /* 3 */ - 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2, /* 4 */ - 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, /* 5 */ - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 6 */ - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 7 */ - 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* 8 */ - 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* 9 */ - 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* a */ - 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* b */ - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 2, 2, /* c */ - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* d */ - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* e */ - 0, 2, 2, 2, 2, 2, 2, 4, 0, 3, 0, 4, 0, 6, 7, 1 /* f */ -}; - -#define LT (1 << 0) -#define GT (1 << 1) -#define GE (1 << 2) -#define LE (1 << 3) -#define CS (1 << 4) -#define HI (1 << 5) -#define CC (1 << 6) -#define LS (1 << 7) -#define EQ (1 << 8) -#define NE (1 << 9) -#define RA (1 << 10) -#define VC (1 << 11) -#define VS (1 << 12) -#define NC (1 << 13) -#define NS (1 << 14) - -static const u16 cond_table[] = { - /* V C N Z */ - /* 0 0 0 0 */ (NE | NC | CC | VC | GE | GT | HI), - /* 0 0 0 1 */ (EQ | NC | CC | VC | GE | LE | LS), - /* 0 0 1 0 */ (NE | NS | CC | VC | LT | LE | HI), - /* 0 0 1 1 */ (EQ | NS | CC | VC | LT | LE | LS), - /* 0 1 0 0 */ (NE | NC | CS | VC | GE | GT | LS), - /* 0 1 0 1 */ (EQ | NC | CS | VC | GE | LE | LS), - /* 0 1 1 0 */ (NE | NS | CS | VC | LT | LE | LS), - /* 0 1 1 1 */ (EQ | NS | CS | VC | LT | LE | LS), - /* 1 0 0 0 */ (NE | NC | CC | VS | LT | LE | HI), - /* 1 0 0 1 */ (EQ | NC | CC | VS | LT | LE | LS), - /* 1 0 1 0 */ (NE | NS | CC | VS | GE | GT | HI), - /* 1 0 1 1 */ (EQ | NS | CC | VS | GE | LE | LS), - /* 1 1 0 0 */ (NE | NC | CS | VS | LT | LE | LS), - /* 1 1 0 1 */ (EQ | NC | CS | VS | LT | LE | LS), - /* 1 1 1 0 */ (NE | NS | CS | VS | GE | GT | LS), - /* 1 1 1 1 */ (EQ | NS | CS | VS | GE | LE | LS), -}; - -/* - * Calculate what the PC will be after executing next instruction - */ -static unsigned find_nextpc(struct pt_regs *regs, int *flags) -{ - unsigned size; - s8 x8; - s16 x16; - s32 x32; - u8 opc, *pc, *sp, *next; - - next = 0; - *flags = SINGLESTEP_PCREL; - - pc = (u8 *) regs->pc; - sp = (u8 *) (regs + 1); - opc = *pc; - - size = mn10300_insn_sizes[opc]; - if (size > 0) { - next = pc + size; - } else { - switch (opc) { - /* Bxx (d8,PC) */ - case 0xc0 ... 0xca: - x8 = 2; - if (cond_table[regs->epsw & 0xf] & (1 << (opc & 0xf))) - x8 = (s8)pc[1]; - next = pc + x8; - *flags |= SINGLESTEP_BRANCH; - break; - - /* JMP (d16,PC) or CALL (d16,PC) */ - case 0xcc: - case 0xcd: - READ_WORD16(pc + 1, &x16); - next = pc + x16; - *flags |= SINGLESTEP_BRANCH; - break; - - /* JMP (d32,PC) or CALL (d32,PC) */ - case 0xdc: - case 0xdd: - READ_WORD32(pc + 1, &x32); - next = pc + x32; - *flags |= SINGLESTEP_BRANCH; - break; - - /* RETF */ - case 0xde: - next = (u8 *)regs->mdr; - *flags &= ~SINGLESTEP_PCREL; - *flags |= SINGLESTEP_BRANCH; - break; - - /* RET */ - case 0xdf: - sp += pc[2]; - READ_WORD32(sp, &x32); - next = (u8 *)x32; - *flags &= ~SINGLESTEP_PCREL; - *flags |= SINGLESTEP_BRANCH; - break; - - case 0xf0: - next = pc + 2; - opc = pc[1]; - if (opc >= 0xf0 && opc <= 0xf7) { - /* JMP (An) / CALLS (An) */ - switch (opc & 3) { - case 0: - next = (u8 *)regs->a0; - break; - case 1: - next = (u8 *)regs->a1; - break; - case 2: - next = (u8 *)regs->a2; - break; - case 3: - next = (u8 *)regs->a3; - break; - } - *flags &= ~SINGLESTEP_PCREL; - *flags |= SINGLESTEP_BRANCH; - } else if (opc == 0xfc) { - /* RETS */ - READ_WORD32(sp, &x32); - next = (u8 *)x32; - *flags &= ~SINGLESTEP_PCREL; - *flags |= SINGLESTEP_BRANCH; - } else if (opc == 0xfd) { - /* RTI */ - READ_WORD32(sp + 4, &x32); - next = (u8 *)x32; - *flags &= ~SINGLESTEP_PCREL; - *flags |= SINGLESTEP_BRANCH; - } - break; - - /* potential 3-byte conditional branches */ - case 0xf8: - next = pc + 3; - opc = pc[1]; - if (opc >= 0xe8 && opc <= 0xeb && - (cond_table[regs->epsw & 0xf] & - (1 << ((opc & 0xf) + 3))) - ) { - READ_BYTE(pc+2, &x8); - next = pc + x8; - *flags |= SINGLESTEP_BRANCH; - } - break; - - case 0xfa: - if (pc[1] == 0xff) { - /* CALLS (d16,PC) */ - READ_WORD16(pc + 2, &x16); - next = pc + x16; - } else - next = pc + 4; - *flags |= SINGLESTEP_BRANCH; - break; - - case 0xfc: - x32 = 6; - if (pc[1] == 0xff) { - /* CALLS (d32,PC) */ - READ_WORD32(pc + 2, &x32); - } - next = pc + x32; - *flags |= SINGLESTEP_BRANCH; - break; - /* LXX (d8,PC) */ - /* SETLB - loads the next four bytes into the LIR reg */ - case 0xd0 ... 0xda: - case 0xdb: - panic("Can't singlestep Lxx/SETLB\n"); - break; - } - } - return (unsigned)next; - -} - -/* - * set up out of place singlestep of some branching instructions - */ -static unsigned __kprobes singlestep_branch_setup(struct pt_regs *regs) -{ - u8 opc, *pc, *sp, *next; - - next = NULL; - pc = (u8 *) regs->pc; - sp = (u8 *) (regs + 1); - - switch (pc[0]) { - case 0xc0 ... 0xca: /* Bxx (d8,PC) */ - case 0xcc: /* JMP (d16,PC) */ - case 0xdc: /* JMP (d32,PC) */ - case 0xf8: /* Bxx (d8,PC) 3-byte version */ - /* don't really need to do anything except cause trap */ - next = pc; - break; - - case 0xcd: /* CALL (d16,PC) */ - pc[1] = 5; - pc[2] = 0; - next = pc + 5; - break; - - case 0xdd: /* CALL (d32,PC) */ - pc[1] = 7; - pc[2] = 0; - pc[3] = 0; - pc[4] = 0; - next = pc + 7; - break; - - case 0xde: /* RETF */ - next = pc + 3; - regs->mdr = (unsigned) next; - break; - - case 0xdf: /* RET */ - sp += pc[2]; - next = pc + 3; - *(unsigned *)sp = (unsigned) next; - break; - - case 0xf0: - next = pc + 2; - opc = pc[1]; - if (opc >= 0xf0 && opc <= 0xf3) { - /* CALLS (An) */ - /* use CALLS (d16,PC) to avoid mucking with An */ - pc[0] = 0xfa; - pc[1] = 0xff; - pc[2] = 4; - pc[3] = 0; - next = pc + 4; - } else if (opc >= 0xf4 && opc <= 0xf7) { - /* JMP (An) */ - next = pc; - } else if (opc == 0xfc) { - /* RETS */ - next = pc + 2; - *(unsigned *) sp = (unsigned) next; - } else if (opc == 0xfd) { - /* RTI */ - next = pc + 2; - *(unsigned *)(sp + 4) = (unsigned) next; - } - break; - - case 0xfa: /* CALLS (d16,PC) */ - pc[2] = 4; - pc[3] = 0; - next = pc + 4; - break; - - case 0xfc: /* CALLS (d32,PC) */ - pc[2] = 6; - pc[3] = 0; - pc[4] = 0; - pc[5] = 0; - next = pc + 6; - break; - - case 0xd0 ... 0xda: /* LXX (d8,PC) */ - case 0xdb: /* SETLB */ - panic("Can't singlestep Lxx/SETLB\n"); - } - - return (unsigned) next; -} - -int __kprobes arch_prepare_kprobe(struct kprobe *p) -{ - return 0; -} - -void __kprobes arch_copy_kprobe(struct kprobe *p) -{ - memcpy(p->ainsn.insn, p->addr, MAX_INSN_SIZE); -} - -void __kprobes arch_arm_kprobe(struct kprobe *p) -{ - *p->addr = BREAKPOINT_INSTRUCTION; - flush_icache_range((unsigned long) p->addr, - (unsigned long) p->addr + sizeof(kprobe_opcode_t)); -} - -void __kprobes arch_disarm_kprobe(struct kprobe *p) -{ -#ifndef CONFIG_MN10300_CACHE_SNOOP - mn10300_dcache_flush(); - mn10300_icache_inv(); -#endif -} - -void arch_remove_kprobe(struct kprobe *p) -{ -} - -static inline -void __kprobes disarm_kprobe(struct kprobe *p, struct pt_regs *regs) -{ - *p->addr = p->opcode; - regs->pc = (unsigned long) p->addr; -#ifndef CONFIG_MN10300_CACHE_SNOOP - mn10300_dcache_flush(); - mn10300_icache_inv(); -#endif -} - -static inline -void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs) -{ - unsigned long nextpc; - - cur_kprobe_orig_pc = regs->pc; - memcpy(cur_kprobe_ss_buf, &p->ainsn.insn[0], MAX_INSN_SIZE); - regs->pc = (unsigned long) cur_kprobe_ss_buf; - - nextpc = find_nextpc(regs, &cur_kprobe_ss_flags); - if (cur_kprobe_ss_flags & SINGLESTEP_PCREL) - cur_kprobe_next_pc = cur_kprobe_orig_pc + (nextpc - regs->pc); - else - cur_kprobe_next_pc = nextpc; - - /* branching instructions need special handling */ - if (cur_kprobe_ss_flags & SINGLESTEP_BRANCH) - nextpc = singlestep_branch_setup(regs); - - cur_kprobe_bp_addr = nextpc; - - *(u8 *) nextpc = BREAKPOINT_INSTRUCTION; - mn10300_dcache_flush_range2((unsigned) cur_kprobe_ss_buf, - sizeof(cur_kprobe_ss_buf)); - mn10300_icache_inv(); -} - -static inline int __kprobes kprobe_handler(struct pt_regs *regs) -{ - struct kprobe *p; - int ret = 0; - unsigned int *addr = (unsigned int *) regs->pc; - - /* We're in an interrupt, but this is clear and BUG()-safe. */ - preempt_disable(); - - /* Check we're not actually recursing */ - if (kprobe_running()) { - /* We *are* holding lock here, so this is safe. - Disarm the probe we just hit, and ignore it. */ - p = get_kprobe(addr); - if (p) { - disarm_kprobe(p, regs); - ret = 1; - } else { - p = cur_kprobe; - if (p->break_handler && p->break_handler(p, regs)) - goto ss_probe; - } - /* If it's not ours, can't be delete race, (we hold lock). */ - goto no_kprobe; - } - - p = get_kprobe(addr); - if (!p) { - if (*addr != BREAKPOINT_INSTRUCTION) { - /* The breakpoint instruction was removed right after - * we hit it. Another cpu has removed either a - * probepoint or a debugger breakpoint at this address. - * In either case, no further handling of this - * interrupt is appropriate. - */ - ret = 1; - } - /* Not one of ours: let kernel handle it */ - goto no_kprobe; - } - - kprobe_status = KPROBE_HIT_ACTIVE; - cur_kprobe = p; - if (p->pre_handler(p, regs)) { - /* handler has already set things up, so skip ss setup */ - return 1; - } - -ss_probe: - prepare_singlestep(p, regs); - kprobe_status = KPROBE_HIT_SS; - return 1; - -no_kprobe: - preempt_enable_no_resched(); - return ret; -} - -/* - * Called after single-stepping. p->addr is the address of the - * instruction whose first byte has been replaced by the "breakpoint" - * instruction. To avoid the SMP problems that can occur when we - * temporarily put back the original opcode to single-step, we - * single-stepped a copy of the instruction. The address of this - * copy is p->ainsn.insn. - */ -static void __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs) -{ - /* we may need to fixup regs/stack after singlestepping a call insn */ - if (cur_kprobe_ss_flags & SINGLESTEP_BRANCH) { - regs->pc = cur_kprobe_orig_pc; - switch (p->ainsn.insn[0]) { - case 0xcd: /* CALL (d16,PC) */ - *(unsigned *) regs->sp = regs->mdr = regs->pc + 5; - break; - case 0xdd: /* CALL (d32,PC) */ - /* fixup mdr and return address on stack */ - *(unsigned *) regs->sp = regs->mdr = regs->pc + 7; - break; - case 0xf0: - if (p->ainsn.insn[1] >= 0xf0 && - p->ainsn.insn[1] <= 0xf3) { - /* CALLS (An) */ - /* fixup MDR and return address on stack */ - regs->mdr = regs->pc + 2; - *(unsigned *) regs->sp = regs->mdr; - } - break; - - case 0xfa: /* CALLS (d16,PC) */ - /* fixup MDR and return address on stack */ - *(unsigned *) regs->sp = regs->mdr = regs->pc + 4; - break; - - case 0xfc: /* CALLS (d32,PC) */ - /* fixup MDR and return address on stack */ - *(unsigned *) regs->sp = regs->mdr = regs->pc + 6; - break; - } - } - - regs->pc = cur_kprobe_next_pc; - cur_kprobe_bp_addr = 0; -} - -static inline int __kprobes post_kprobe_handler(struct pt_regs *regs) -{ - if (!kprobe_running()) - return 0; - - if (cur_kprobe->post_handler) - cur_kprobe->post_handler(cur_kprobe, regs, 0); - - resume_execution(cur_kprobe, regs); - reset_current_kprobe(); - preempt_enable_no_resched(); - return 1; -} - -/* Interrupts disabled, kprobe_lock held. */ -static inline -int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr) -{ - if (cur_kprobe->fault_handler && - cur_kprobe->fault_handler(cur_kprobe, regs, trapnr)) - return 1; - - if (kprobe_status & KPROBE_HIT_SS) { - resume_execution(cur_kprobe, regs); - reset_current_kprobe(); - preempt_enable_no_resched(); - } - return 0; -} - -/* - * Wrapper routine to for handling exceptions. - */ -int __kprobes kprobe_exceptions_notify(struct notifier_block *self, - unsigned long val, void *data) -{ - struct die_args *args = data; - - switch (val) { - case DIE_BREAKPOINT: - if (cur_kprobe_bp_addr != args->regs->pc) { - if (kprobe_handler(args->regs)) - return NOTIFY_STOP; - } else { - if (post_kprobe_handler(args->regs)) - return NOTIFY_STOP; - } - break; - case DIE_GPF: - if (kprobe_running() && - kprobe_fault_handler(args->regs, args->trapnr)) - return NOTIFY_STOP; - break; - default: - break; - } - return NOTIFY_DONE; -} - -/* Jprobes support. */ -static struct pt_regs jprobe_saved_regs; -static struct pt_regs *jprobe_saved_regs_location; -static kprobe_opcode_t jprobe_saved_stack[MAX_STACK_SIZE]; - -int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) -{ - struct jprobe *jp = container_of(p, struct jprobe, kp); - - jprobe_saved_regs_location = regs; - memcpy(&jprobe_saved_regs, regs, sizeof(struct pt_regs)); - - /* Save a whole stack frame, this gets arguments - * pushed onto the stack after using up all the - * arg registers. - */ - memcpy(&jprobe_saved_stack, regs + 1, sizeof(jprobe_saved_stack)); - - /* setup return addr to the jprobe handler routine */ - regs->pc = (unsigned long) jp->entry; - return 1; -} - -void __kprobes jprobe_return(void) -{ - void *orig_sp = jprobe_saved_regs_location + 1; - - preempt_enable_no_resched(); - asm volatile(" mov %0,sp\n" - ".globl jprobe_return_bp_addr\n" - "jprobe_return_bp_addr:\n\t" - " .byte 0xff\n" - : : "d" (orig_sp)); -} - -extern void jprobe_return_bp_addr(void); - -int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) -{ - u8 *addr = (u8 *) regs->pc; - - if (addr == (u8 *) jprobe_return_bp_addr) { - if (jprobe_saved_regs_location != regs) { - printk(KERN_ERR"JPROBE:" - " Current regs (%p) does not match saved regs" - " (%p).\n", - regs, jprobe_saved_regs_location); - BUG(); - } - - /* Restore old register state. - */ - memcpy(regs, &jprobe_saved_regs, sizeof(struct pt_regs)); - - memcpy(regs + 1, &jprobe_saved_stack, - sizeof(jprobe_saved_stack)); - return 1; - } - return 0; -} - -int __init arch_init_kprobes(void) -{ - return 0; -} |