diff options
Diffstat (limited to 'arch/tile/kernel/single_step.c')
| -rw-r--r-- | arch/tile/kernel/single_step.c | 786 |
1 files changed, 0 insertions, 786 deletions
diff --git a/arch/tile/kernel/single_step.c b/arch/tile/kernel/single_step.c deleted file mode 100644 index 479d8033a801..000000000000 --- a/arch/tile/kernel/single_step.c +++ /dev/null @@ -1,786 +0,0 @@ -/* - * Copyright 2010 Tilera Corporation. All Rights Reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation, version 2. - * - * 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, GOOD TITLE or - * NON INFRINGEMENT. See the GNU General Public License for - * more details. - * - * A code-rewriter that enables instruction single-stepping. - */ - -#include <linux/smp.h> -#include <linux/ptrace.h> -#include <linux/slab.h> -#include <linux/thread_info.h> -#include <linux/uaccess.h> -#include <linux/mman.h> -#include <linux/types.h> -#include <linux/err.h> -#include <linux/prctl.h> -#include <asm/cacheflush.h> -#include <asm/traps.h> -#include <linux/uaccess.h> -#include <asm/unaligned.h> -#include <arch/abi.h> -#include <arch/spr_def.h> -#include <arch/opcode.h> - - -#ifndef __tilegx__ /* Hardware support for single step unavailable. */ - -#define signExtend17(val) sign_extend((val), 17) -#define TILE_X1_MASK (0xffffffffULL << 31) - -enum mem_op { - MEMOP_NONE, - MEMOP_LOAD, - MEMOP_STORE, - MEMOP_LOAD_POSTINCR, - MEMOP_STORE_POSTINCR -}; - -static inline tilepro_bundle_bits set_BrOff_X1(tilepro_bundle_bits n, - s32 offset) -{ - tilepro_bundle_bits result; - - /* mask out the old offset */ - tilepro_bundle_bits mask = create_BrOff_X1(-1); - result = n & (~mask); - - /* or in the new offset */ - result |= create_BrOff_X1(offset); - - return result; -} - -static inline tilepro_bundle_bits move_X1(tilepro_bundle_bits n, int dest, - int src) -{ - tilepro_bundle_bits result; - tilepro_bundle_bits op; - - result = n & (~TILE_X1_MASK); - - op = create_Opcode_X1(SPECIAL_0_OPCODE_X1) | - create_RRROpcodeExtension_X1(OR_SPECIAL_0_OPCODE_X1) | - create_Dest_X1(dest) | - create_SrcB_X1(TREG_ZERO) | - create_SrcA_X1(src) ; - - result |= op; - return result; -} - -static inline tilepro_bundle_bits nop_X1(tilepro_bundle_bits n) -{ - return move_X1(n, TREG_ZERO, TREG_ZERO); -} - -static inline tilepro_bundle_bits addi_X1( - tilepro_bundle_bits n, int dest, int src, int imm) -{ - n &= ~TILE_X1_MASK; - - n |= (create_SrcA_X1(src) | - create_Dest_X1(dest) | - create_Imm8_X1(imm) | - create_S_X1(0) | - create_Opcode_X1(IMM_0_OPCODE_X1) | - create_ImmOpcodeExtension_X1(ADDI_IMM_0_OPCODE_X1)); - - return n; -} - -static tilepro_bundle_bits rewrite_load_store_unaligned( - struct single_step_state *state, - tilepro_bundle_bits bundle, - struct pt_regs *regs, - enum mem_op mem_op, - int size, int sign_ext) -{ - unsigned char __user *addr; - int val_reg, addr_reg, err, val; - int align_ctl; - - align_ctl = unaligned_fixup; - switch (task_thread_info(current)->align_ctl) { - case PR_UNALIGN_NOPRINT: - align_ctl = 1; - break; - case PR_UNALIGN_SIGBUS: - align_ctl = 0; - break; - } - - /* Get address and value registers */ - if (bundle & TILEPRO_BUNDLE_Y_ENCODING_MASK) { - addr_reg = get_SrcA_Y2(bundle); - val_reg = get_SrcBDest_Y2(bundle); - } else if (mem_op == MEMOP_LOAD || mem_op == MEMOP_LOAD_POSTINCR) { - addr_reg = get_SrcA_X1(bundle); - val_reg = get_Dest_X1(bundle); - } else { - addr_reg = get_SrcA_X1(bundle); - val_reg = get_SrcB_X1(bundle); - } - - /* - * If registers are not GPRs, don't try to handle it. - * - * FIXME: we could handle non-GPR loads by getting the real value - * from memory, writing it to the single step buffer, using a - * temp_reg to hold a pointer to that memory, then executing that - * instruction and resetting temp_reg. For non-GPR stores, it's a - * little trickier; we could use the single step buffer for that - * too, but we'd have to add some more state bits so that we could - * call back in here to copy that value to the real target. For - * now, we just handle the simple case. - */ - if ((val_reg >= PTREGS_NR_GPRS && - (val_reg != TREG_ZERO || - mem_op == MEMOP_LOAD || - mem_op == MEMOP_LOAD_POSTINCR)) || - addr_reg >= PTREGS_NR_GPRS) - return bundle; - - /* If it's aligned, don't handle it specially */ - addr = (void __user *)regs->regs[addr_reg]; - if (((unsigned long)addr % size) == 0) - return bundle; - - /* - * Return SIGBUS with the unaligned address, if requested. - * Note that we return SIGBUS even for completely invalid addresses - * as long as they are in fact unaligned; this matches what the - * tilepro hardware would be doing, if it could provide us with the - * actual bad address in an SPR, which it doesn't. - */ - if (align_ctl == 0) { - siginfo_t info; - - clear_siginfo(&info); - info.si_signo = SIGBUS; - info.si_code = BUS_ADRALN; - info.si_addr = addr; - - trace_unhandled_signal("unaligned trap", regs, - (unsigned long)addr, SIGBUS); - force_sig_info(info.si_signo, &info, current); - return (tilepro_bundle_bits) 0; - } - - /* Handle unaligned load/store */ - if (mem_op == MEMOP_LOAD || mem_op == MEMOP_LOAD_POSTINCR) { - unsigned short val_16; - switch (size) { - case 2: - err = copy_from_user(&val_16, addr, sizeof(val_16)); - val = sign_ext ? ((short)val_16) : val_16; - break; - case 4: - err = copy_from_user(&val, addr, sizeof(val)); - break; - default: - BUG(); - } - if (err == 0) { - state->update_reg = val_reg; - state->update_value = val; - state->update = 1; - } - } else { - unsigned short val_16; - val = (val_reg == TREG_ZERO) ? 0 : regs->regs[val_reg]; - switch (size) { - case 2: - val_16 = val; - err = copy_to_user(addr, &val_16, sizeof(val_16)); - break; - case 4: - err = copy_to_user(addr, &val, sizeof(val)); - break; - default: - BUG(); - } - } - - if (err) { - siginfo_t info; - - clear_siginfo(&info); - info.si_signo = SIGBUS; - info.si_code = BUS_ADRALN; - info.si_addr = addr; - - trace_unhandled_signal("bad address for unaligned fixup", regs, - (unsigned long)addr, SIGBUS); - force_sig_info(info.si_signo, &info, current); - return (tilepro_bundle_bits) 0; - } - - if (unaligned_printk || unaligned_fixup_count == 0) { - pr_info("Process %d/%s: PC %#lx: Fixup of unaligned %s at %#lx\n", - current->pid, current->comm, regs->pc, - mem_op == MEMOP_LOAD || mem_op == MEMOP_LOAD_POSTINCR ? - "load" : "store", - (unsigned long)addr); - if (!unaligned_printk) { -#define P pr_info -P("\n"); -P("Unaligned fixups in the kernel will slow your application considerably.\n"); -P("To find them, write a \"1\" to /proc/sys/tile/unaligned_fixup/printk,\n"); -P("which requests the kernel show all unaligned fixups, or write a \"0\"\n"); -P("to /proc/sys/tile/unaligned_fixup/enabled, in which case each unaligned\n"); -P("access will become a SIGBUS you can debug. No further warnings will be\n"); -P("shown so as to avoid additional slowdown, but you can track the number\n"); -P("of fixups performed via /proc/sys/tile/unaligned_fixup/count.\n"); -P("Use the tile-addr2line command (see \"info addr2line\") to decode PCs.\n"); -P("\n"); -#undef P - } - } - ++unaligned_fixup_count; - - if (bundle & TILEPRO_BUNDLE_Y_ENCODING_MASK) { - /* Convert the Y2 instruction to a prefetch. */ - bundle &= ~(create_SrcBDest_Y2(-1) | - create_Opcode_Y2(-1)); - bundle |= (create_SrcBDest_Y2(TREG_ZERO) | - create_Opcode_Y2(LW_OPCODE_Y2)); - /* Replace the load postincr with an addi */ - } else if (mem_op == MEMOP_LOAD_POSTINCR) { - bundle = addi_X1(bundle, addr_reg, addr_reg, - get_Imm8_X1(bundle)); - /* Replace the store postincr with an addi */ - } else if (mem_op == MEMOP_STORE_POSTINCR) { - bundle = addi_X1(bundle, addr_reg, addr_reg, - get_Dest_Imm8_X1(bundle)); - } else { - /* Convert the X1 instruction to a nop. */ - bundle &= ~(create_Opcode_X1(-1) | - create_UnShOpcodeExtension_X1(-1) | - create_UnOpcodeExtension_X1(-1)); - bundle |= (create_Opcode_X1(SHUN_0_OPCODE_X1) | - create_UnShOpcodeExtension_X1( - UN_0_SHUN_0_OPCODE_X1) | - create_UnOpcodeExtension_X1( - NOP_UN_0_SHUN_0_OPCODE_X1)); - } - - return bundle; -} - -/* - * Called after execve() has started the new image. This allows us - * to reset the info state. Note that the the mmap'ed memory, if there - * was any, has already been unmapped by the exec. - */ -void single_step_execve(void) -{ - struct thread_info *ti = current_thread_info(); - kfree(ti->step_state); - ti->step_state = NULL; -} - -/* - * single_step_once() - entry point when single stepping has been triggered. - * @regs: The machine register state - * - * When we arrive at this routine via a trampoline, the single step - * engine copies the executing bundle to the single step buffer. - * If the instruction is a condition branch, then the target is - * reset to one past the next instruction. If the instruction - * sets the lr, then that is noted. If the instruction is a jump - * or call, then the new target pc is preserved and the current - * bundle instruction set to null. - * - * The necessary post-single-step rewriting information is stored in - * single_step_state-> We use data segment values because the - * stack will be rewound when we run the rewritten single-stepped - * instruction. - */ -void single_step_once(struct pt_regs *regs) -{ - extern tilepro_bundle_bits __single_step_ill_insn; - extern tilepro_bundle_bits __single_step_j_insn; - extern tilepro_bundle_bits __single_step_addli_insn; - extern tilepro_bundle_bits __single_step_auli_insn; - struct thread_info *info = (void *)current_thread_info(); - struct single_step_state *state = info->step_state; - int is_single_step = test_ti_thread_flag(info, TIF_SINGLESTEP); - tilepro_bundle_bits __user *buffer, *pc; - tilepro_bundle_bits bundle; - int temp_reg; - int target_reg = TREG_LR; - int err; - enum mem_op mem_op = MEMOP_NONE; - int size = 0, sign_ext = 0; /* happy compiler */ - int align_ctl; - - align_ctl = unaligned_fixup; - switch (task_thread_info(current)->align_ctl) { - case PR_UNALIGN_NOPRINT: - align_ctl = 1; - break; - case PR_UNALIGN_SIGBUS: - align_ctl = 0; - break; - } - - asm( -" .pushsection .rodata.single_step\n" -" .align 8\n" -" .globl __single_step_ill_insn\n" -"__single_step_ill_insn:\n" -" ill\n" -" .globl __single_step_addli_insn\n" -"__single_step_addli_insn:\n" -" { nop; addli r0, zero, 0 }\n" -" .globl __single_step_auli_insn\n" -"__single_step_auli_insn:\n" -" { nop; auli r0, r0, 0 }\n" -" .globl __single_step_j_insn\n" -"__single_step_j_insn:\n" -" j .\n" -" .popsection\n" - ); - - /* - * Enable interrupts here to allow touching userspace and the like. - * The callers expect this: do_trap() already has interrupts - * enabled, and do_work_pending() handles functions that enable - * interrupts internally. - */ - local_irq_enable(); - - if (state == NULL) { - /* allocate a page of writable, executable memory */ - state = kmalloc(sizeof(struct single_step_state), GFP_KERNEL); - if (state == NULL) { - pr_err("Out of kernel memory trying to single-step\n"); - return; - } - - /* allocate a cache line of writable, executable memory */ - buffer = (void __user *) vm_mmap(NULL, 0, 64, - PROT_EXEC | PROT_READ | PROT_WRITE, - MAP_PRIVATE | MAP_ANONYMOUS, - 0); - - if (IS_ERR((void __force *)buffer)) { - kfree(state); - pr_err("Out of kernel pages trying to single-step\n"); - return; - } - - state->buffer = buffer; - state->is_enabled = 0; - - info->step_state = state; - - /* Validate our stored instruction patterns */ - BUG_ON(get_Opcode_X1(__single_step_addli_insn) != - ADDLI_OPCODE_X1); - BUG_ON(get_Opcode_X1(__single_step_auli_insn) != - AULI_OPCODE_X1); - BUG_ON(get_SrcA_X1(__single_step_addli_insn) != TREG_ZERO); - BUG_ON(get_Dest_X1(__single_step_addli_insn) != 0); - BUG_ON(get_JOffLong_X1(__single_step_j_insn) != 0); - } - - /* - * If we are returning from a syscall, we still haven't hit the - * "ill" for the swint1 instruction. So back the PC up to be - * pointing at the swint1, but we'll actually return directly - * back to the "ill" so we come back in via SIGILL as if we - * had "executed" the swint1 without ever being in kernel space. - */ - if (regs->faultnum == INT_SWINT_1) - regs->pc -= 8; - - pc = (tilepro_bundle_bits __user *)(regs->pc); - if (get_user(bundle, pc) != 0) { - pr_err("Couldn't read instruction at %p trying to step\n", pc); - return; - } - - /* We'll follow the instruction with 2 ill op bundles */ - state->orig_pc = (unsigned long)pc; - state->next_pc = (unsigned long)(pc + 1); - state->branch_next_pc = 0; - state->update = 0; - - if (!(bundle & TILEPRO_BUNDLE_Y_ENCODING_MASK)) { - /* two wide, check for control flow */ - int opcode = get_Opcode_X1(bundle); - - switch (opcode) { - /* branches */ - case BRANCH_OPCODE_X1: - { - s32 offset = signExtend17(get_BrOff_X1(bundle)); - - /* - * For branches, we use a rewriting trick to let the - * hardware evaluate whether the branch is taken or - * untaken. We record the target offset and then - * rewrite the branch instruction to target 1 insn - * ahead if the branch is taken. We then follow the - * rewritten branch with two bundles, each containing - * an "ill" instruction. The supervisor examines the - * pc after the single step code is executed, and if - * the pc is the first ill instruction, then the - * branch (if any) was not taken. If the pc is the - * second ill instruction, then the branch was - * taken. The new pc is computed for these cases, and - * inserted into the registers for the thread. If - * the pc is the start of the single step code, then - * an exception or interrupt was taken before the - * code started processing, and the same "original" - * pc is restored. This change, different from the - * original implementation, has the advantage of - * executing a single user instruction. - */ - state->branch_next_pc = (unsigned long)(pc + offset); - - /* rewrite branch offset to go forward one bundle */ - bundle = set_BrOff_X1(bundle, 2); - } - break; - - /* jumps */ - case JALB_OPCODE_X1: - case JALF_OPCODE_X1: - state->update = 1; - state->next_pc = - (unsigned long) (pc + get_JOffLong_X1(bundle)); - break; - - case JB_OPCODE_X1: - case JF_OPCODE_X1: - state->next_pc = - (unsigned long) (pc + get_JOffLong_X1(bundle)); - bundle = nop_X1(bundle); - break; - - case SPECIAL_0_OPCODE_X1: - switch (get_RRROpcodeExtension_X1(bundle)) { - /* jump-register */ - case JALRP_SPECIAL_0_OPCODE_X1: - case JALR_SPECIAL_0_OPCODE_X1: - state->update = 1; - state->next_pc = - regs->regs[get_SrcA_X1(bundle)]; - break; - - case JRP_SPECIAL_0_OPCODE_X1: - case JR_SPECIAL_0_OPCODE_X1: - state->next_pc = - regs->regs[get_SrcA_X1(bundle)]; - bundle = nop_X1(bundle); - break; - - case LNK_SPECIAL_0_OPCODE_X1: - state->update = 1; - target_reg = get_Dest_X1(bundle); - break; - - /* stores */ - case SH_SPECIAL_0_OPCODE_X1: - mem_op = MEMOP_STORE; - size = 2; - break; - - case SW_SPECIAL_0_OPCODE_X1: - mem_op = MEMOP_STORE; - size = 4; - break; - } - break; - - /* loads and iret */ - case SHUN_0_OPCODE_X1: - if (get_UnShOpcodeExtension_X1(bundle) == - UN_0_SHUN_0_OPCODE_X1) { - switch (get_UnOpcodeExtension_X1(bundle)) { - case LH_UN_0_SHUN_0_OPCODE_X1: - mem_op = MEMOP_LOAD; - size = 2; - sign_ext = 1; - break; - - case LH_U_UN_0_SHUN_0_OPCODE_X1: - mem_op = MEMOP_LOAD; - size = 2; - sign_ext = 0; - break; - - case LW_UN_0_SHUN_0_OPCODE_X1: - mem_op = MEMOP_LOAD; - size = 4; - break; - - case IRET_UN_0_SHUN_0_OPCODE_X1: - { - unsigned long ex0_0 = __insn_mfspr( - SPR_EX_CONTEXT_0_0); - unsigned long ex0_1 = __insn_mfspr( - SPR_EX_CONTEXT_0_1); - /* - * Special-case it if we're iret'ing - * to PL0 again. Otherwise just let - * it run and it will generate SIGILL. - */ - if (EX1_PL(ex0_1) == USER_PL) { - state->next_pc = ex0_0; - regs->ex1 = ex0_1; - bundle = nop_X1(bundle); - } - } - } - } - break; - - /* postincrement operations */ - case IMM_0_OPCODE_X1: - switch (get_ImmOpcodeExtension_X1(bundle)) { - case LWADD_IMM_0_OPCODE_X1: - mem_op = MEMOP_LOAD_POSTINCR; - size = 4; - break; - - case LHADD_IMM_0_OPCODE_X1: - mem_op = MEMOP_LOAD_POSTINCR; - size = 2; - sign_ext = 1; - break; - - case LHADD_U_IMM_0_OPCODE_X1: - mem_op = MEMOP_LOAD_POSTINCR; - size = 2; - sign_ext = 0; - break; - - case SWADD_IMM_0_OPCODE_X1: - mem_op = MEMOP_STORE_POSTINCR; - size = 4; - break; - - case SHADD_IMM_0_OPCODE_X1: - mem_op = MEMOP_STORE_POSTINCR; - size = 2; - break; - - default: - break; - } - break; - } - - if (state->update) { - /* - * Get an available register. We start with a - * bitmask with 1's for available registers. - * We truncate to the low 32 registers since - * we are guaranteed to have set bits in the - * low 32 bits, then use ctz to pick the first. - */ - u32 mask = (u32) ~((1ULL << get_Dest_X0(bundle)) | - (1ULL << get_SrcA_X0(bundle)) | - (1ULL << get_SrcB_X0(bundle)) | - (1ULL << target_reg)); - temp_reg = __builtin_ctz(mask); - state->update_reg = temp_reg; - state->update_value = regs->regs[temp_reg]; - regs->regs[temp_reg] = (unsigned long) (pc+1); - regs->flags |= PT_FLAGS_RESTORE_REGS; - bundle = move_X1(bundle, target_reg, temp_reg); - } - } else { - int opcode = get_Opcode_Y2(bundle); - - switch (opcode) { - /* loads */ - case LH_OPCODE_Y2: - mem_op = MEMOP_LOAD; - size = 2; - sign_ext = 1; - break; - - case LH_U_OPCODE_Y2: - mem_op = MEMOP_LOAD; - size = 2; - sign_ext = 0; - break; - - case LW_OPCODE_Y2: - mem_op = MEMOP_LOAD; - size = 4; - break; - - /* stores */ - case SH_OPCODE_Y2: - mem_op = MEMOP_STORE; - size = 2; - break; - - case SW_OPCODE_Y2: - mem_op = MEMOP_STORE; - size = 4; - break; - } - } - - /* - * Check if we need to rewrite an unaligned load/store. - * Returning zero is a special value meaning we generated a signal. - */ - if (mem_op != MEMOP_NONE && align_ctl >= 0) { - bundle = rewrite_load_store_unaligned(state, bundle, regs, - mem_op, size, sign_ext); - if (bundle == 0) - return; - } - - /* write the bundle to our execution area */ - buffer = state->buffer; - err = __put_user(bundle, buffer++); - - /* - * If we're really single-stepping, we take an INT_ILL after. - * If we're just handling an unaligned access, we can just - * jump directly back to where we were in user code. - */ - if (is_single_step) { - err |= __put_user(__single_step_ill_insn, buffer++); - err |= __put_user(__single_step_ill_insn, buffer++); - } else { - long delta; - - if (state->update) { - /* We have some state to update; do it inline */ - int ha16; - bundle = __single_step_addli_insn; - bundle |= create_Dest_X1(state->update_reg); - bundle |= create_Imm16_X1(state->update_value); - err |= __put_user(bundle, buffer++); - bundle = __single_step_auli_insn; - bundle |= create_Dest_X1(state->update_reg); - bundle |= create_SrcA_X1(state->update_reg); - ha16 = (state->update_value + 0x8000) >> 16; - bundle |= create_Imm16_X1(ha16); - err |= __put_user(bundle, buffer++); - state->update = 0; - } - - /* End with a jump back to the next instruction */ - delta = ((regs->pc + TILEPRO_BUNDLE_SIZE_IN_BYTES) - - (unsigned long)buffer) >> - TILEPRO_LOG2_BUNDLE_ALIGNMENT_IN_BYTES; - bundle = __single_step_j_insn; - bundle |= create_JOffLong_X1(delta); - err |= __put_user(bundle, buffer++); - } - - if (err) { - pr_err("Fault when writing to single-step buffer\n"); - return; - } - - /* - * Flush the buffer. - * We do a local flush only, since this is a thread-specific buffer. - */ - __flush_icache_range((unsigned long)state->buffer, - (unsigned long)buffer); - - /* Indicate enabled */ - state->is_enabled = is_single_step; - regs->pc = (unsigned long)state->buffer; - - /* Fault immediately if we are coming back from a syscall. */ - if (regs->faultnum == INT_SWINT_1) - regs->pc += 8; -} - -#else - -static DEFINE_PER_CPU(unsigned long, ss_saved_pc); - - -/* - * Called directly on the occasion of an interrupt. - * - * If the process doesn't have single step set, then we use this as an - * opportunity to turn single step off. - * - * It has been mentioned that we could conditionally turn off single stepping - * on each entry into the kernel and rely on single_step_once to turn it - * on for the processes that matter (as we already do), but this - * implementation is somewhat more efficient in that we muck with registers - * once on a bum interrupt rather than on every entry into the kernel. - * - * If SINGLE_STEP_CONTROL_K has CANCELED set, then an interrupt occurred, - * so we have to run through this process again before we can say that an - * instruction has executed. - * - * swint will set CANCELED, but it's a legitimate instruction. Fortunately - * it changes the PC. If it hasn't changed, then we know that the interrupt - * wasn't generated by swint and we'll need to run this process again before - * we can say an instruction has executed. - * - * If either CANCELED == 0 or the PC's changed, we send out SIGTRAPs and get - * on with our lives. - */ - -void gx_singlestep_handle(struct pt_regs *regs, int fault_num) -{ - unsigned long *ss_pc = this_cpu_ptr(&ss_saved_pc); - struct thread_info *info = (void *)current_thread_info(); - int is_single_step = test_ti_thread_flag(info, TIF_SINGLESTEP); - unsigned long control = __insn_mfspr(SPR_SINGLE_STEP_CONTROL_K); - - if (is_single_step == 0) { - __insn_mtspr(SPR_SINGLE_STEP_EN_K_K, 0); - - } else if ((*ss_pc != regs->pc) || - (!(control & SPR_SINGLE_STEP_CONTROL_1__CANCELED_MASK))) { - - control |= SPR_SINGLE_STEP_CONTROL_1__CANCELED_MASK; - control |= SPR_SINGLE_STEP_CONTROL_1__INHIBIT_MASK; - __insn_mtspr(SPR_SINGLE_STEP_CONTROL_K, control); - send_sigtrap(current, regs); - } -} - - -/* - * Called from need_singlestep. Set up the control registers and the enable - * register, then return back. - */ - -void single_step_once(struct pt_regs *regs) -{ - unsigned long *ss_pc = this_cpu_ptr(&ss_saved_pc); - unsigned long control = __insn_mfspr(SPR_SINGLE_STEP_CONTROL_K); - - *ss_pc = regs->pc; - control |= SPR_SINGLE_STEP_CONTROL_1__CANCELED_MASK; - control |= SPR_SINGLE_STEP_CONTROL_1__INHIBIT_MASK; - __insn_mtspr(SPR_SINGLE_STEP_CONTROL_K, control); - __insn_mtspr(SPR_SINGLE_STEP_EN_K_K, 1 << USER_PL); -} - -void single_step_execve(void) -{ - /* Nothing */ -} - -#endif /* !__tilegx__ */ |