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Diffstat (limited to 'arch/ia64/kernel/kprobes.c')
-rw-r--r--arch/ia64/kernel/kprobes.c1005
1 files changed, 0 insertions, 1005 deletions
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
deleted file mode 100644
index b8356edbde65..000000000000
--- a/arch/ia64/kernel/kprobes.c
+++ /dev/null
@@ -1,1005 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Kernel Probes (KProbes)
- * arch/ia64/kernel/kprobes.c
- *
- * Copyright (C) IBM Corporation, 2002, 2004
- * Copyright (C) Intel Corporation, 2005
- *
- * 2005-Apr Rusty Lynch <rusty.lynch@intel.com> and Anil S Keshavamurthy
- * <anil.s.keshavamurthy@intel.com> adapted from i386
- */
-
-#include <linux/kprobes.h>
-#include <linux/ptrace.h>
-#include <linux/string.h>
-#include <linux/slab.h>
-#include <linux/preempt.h>
-#include <linux/extable.h>
-#include <linux/kdebug.h>
-
-#include <asm/pgtable.h>
-#include <asm/sections.h>
-#include <asm/exception.h>
-
-DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
-DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
-
-struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}};
-
-enum instruction_type {A, I, M, F, B, L, X, u};
-static enum instruction_type bundle_encoding[32][3] = {
- { M, I, I }, /* 00 */
- { M, I, I }, /* 01 */
- { M, I, I }, /* 02 */
- { M, I, I }, /* 03 */
- { M, L, X }, /* 04 */
- { M, L, X }, /* 05 */
- { u, u, u }, /* 06 */
- { u, u, u }, /* 07 */
- { M, M, I }, /* 08 */
- { M, M, I }, /* 09 */
- { M, M, I }, /* 0A */
- { M, M, I }, /* 0B */
- { M, F, I }, /* 0C */
- { M, F, I }, /* 0D */
- { M, M, F }, /* 0E */
- { M, M, F }, /* 0F */
- { M, I, B }, /* 10 */
- { M, I, B }, /* 11 */
- { M, B, B }, /* 12 */
- { M, B, B }, /* 13 */
- { u, u, u }, /* 14 */
- { u, u, u }, /* 15 */
- { B, B, B }, /* 16 */
- { B, B, B }, /* 17 */
- { M, M, B }, /* 18 */
- { M, M, B }, /* 19 */
- { u, u, u }, /* 1A */
- { u, u, u }, /* 1B */
- { M, F, B }, /* 1C */
- { M, F, B }, /* 1D */
- { u, u, u }, /* 1E */
- { u, u, u }, /* 1F */
-};
-
-/* Insert a long branch code */
-static void __kprobes set_brl_inst(void *from, void *to)
-{
- s64 rel = ((s64) to - (s64) from) >> 4;
- bundle_t *brl;
- brl = (bundle_t *) ((u64) from & ~0xf);
- brl->quad0.template = 0x05; /* [MLX](stop) */
- brl->quad0.slot0 = NOP_M_INST; /* nop.m 0x0 */
- brl->quad0.slot1_p0 = ((rel >> 20) & 0x7fffffffff) << 2;
- brl->quad1.slot1_p1 = (((rel >> 20) & 0x7fffffffff) << 2) >> (64 - 46);
- /* brl.cond.sptk.many.clr rel<<4 (qp=0) */
- brl->quad1.slot2 = BRL_INST(rel >> 59, rel & 0xfffff);
-}
-
-/*
- * In this function we check to see if the instruction
- * is IP relative instruction and update the kprobe
- * inst flag accordingly
- */
-static void __kprobes update_kprobe_inst_flag(uint template, uint slot,
- uint major_opcode,
- unsigned long kprobe_inst,
- struct kprobe *p)
-{
- p->ainsn.inst_flag = 0;
- p->ainsn.target_br_reg = 0;
- p->ainsn.slot = slot;
-
- /* Check for Break instruction
- * Bits 37:40 Major opcode to be zero
- * Bits 27:32 X6 to be zero
- * Bits 32:35 X3 to be zero
- */
- if ((!major_opcode) && (!((kprobe_inst >> 27) & 0x1FF)) ) {
- /* is a break instruction */
- p->ainsn.inst_flag |= INST_FLAG_BREAK_INST;
- return;
- }
-
- if (bundle_encoding[template][slot] == B) {
- switch (major_opcode) {
- case INDIRECT_CALL_OPCODE:
- p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
- p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
- break;
- case IP_RELATIVE_PREDICT_OPCODE:
- case IP_RELATIVE_BRANCH_OPCODE:
- p->ainsn.inst_flag |= INST_FLAG_FIX_RELATIVE_IP_ADDR;
- break;
- case IP_RELATIVE_CALL_OPCODE:
- p->ainsn.inst_flag |= INST_FLAG_FIX_RELATIVE_IP_ADDR;
- p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
- p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
- break;
- }
- } else if (bundle_encoding[template][slot] == X) {
- switch (major_opcode) {
- case LONG_CALL_OPCODE:
- p->ainsn.inst_flag |= INST_FLAG_FIX_BRANCH_REG;
- p->ainsn.target_br_reg = ((kprobe_inst >> 6) & 0x7);
- break;
- }
- }
- return;
-}
-
-/*
- * In this function we check to see if the instruction
- * (qp) cmpx.crel.ctype p1,p2=r2,r3
- * on which we are inserting kprobe is cmp instruction
- * with ctype as unc.
- */
-static uint __kprobes is_cmp_ctype_unc_inst(uint template, uint slot,
- uint major_opcode,
- unsigned long kprobe_inst)
-{
- cmp_inst_t cmp_inst;
- uint ctype_unc = 0;
-
- if (!((bundle_encoding[template][slot] == I) ||
- (bundle_encoding[template][slot] == M)))
- goto out;
-
- if (!((major_opcode == 0xC) || (major_opcode == 0xD) ||
- (major_opcode == 0xE)))
- goto out;
-
- cmp_inst.l = kprobe_inst;
- if ((cmp_inst.f.x2 == 0) || (cmp_inst.f.x2 == 1)) {
- /* Integer compare - Register Register (A6 type)*/
- if ((cmp_inst.f.tb == 0) && (cmp_inst.f.ta == 0)
- &&(cmp_inst.f.c == 1))
- ctype_unc = 1;
- } else if ((cmp_inst.f.x2 == 2)||(cmp_inst.f.x2 == 3)) {
- /* Integer compare - Immediate Register (A8 type)*/
- if ((cmp_inst.f.ta == 0) &&(cmp_inst.f.c == 1))
- ctype_unc = 1;
- }
-out:
- return ctype_unc;
-}
-
-/*
- * In this function we check to see if the instruction
- * on which we are inserting kprobe is supported.
- * Returns qp value if supported
- * Returns -EINVAL if unsupported
- */
-static int __kprobes unsupported_inst(uint template, uint slot,
- uint major_opcode,
- unsigned long kprobe_inst,
- unsigned long addr)
-{
- int qp;
-
- qp = kprobe_inst & 0x3f;
- if (is_cmp_ctype_unc_inst(template, slot, major_opcode, kprobe_inst)) {
- if (slot == 1 && qp) {
- printk(KERN_WARNING "Kprobes on cmp unc "
- "instruction on slot 1 at <0x%lx> "
- "is not supported\n", addr);
- return -EINVAL;
-
- }
- qp = 0;
- }
- else if (bundle_encoding[template][slot] == I) {
- if (major_opcode == 0) {
- /*
- * Check for Integer speculation instruction
- * - Bit 33-35 to be equal to 0x1
- */
- if (((kprobe_inst >> 33) & 0x7) == 1) {
- printk(KERN_WARNING
- "Kprobes on speculation inst at <0x%lx> not supported\n",
- addr);
- return -EINVAL;
- }
- /*
- * IP relative mov instruction
- * - Bit 27-35 to be equal to 0x30
- */
- if (((kprobe_inst >> 27) & 0x1FF) == 0x30) {
- printk(KERN_WARNING
- "Kprobes on \"mov r1=ip\" at <0x%lx> not supported\n",
- addr);
- return -EINVAL;
-
- }
- }
- else if ((major_opcode == 5) && !(kprobe_inst & (0xFUl << 33)) &&
- (kprobe_inst & (0x1UL << 12))) {
- /* test bit instructions, tbit,tnat,tf
- * bit 33-36 to be equal to 0
- * bit 12 to be equal to 1
- */
- if (slot == 1 && qp) {
- printk(KERN_WARNING "Kprobes on test bit "
- "instruction on slot at <0x%lx> "
- "is not supported\n", addr);
- return -EINVAL;
- }
- qp = 0;
- }
- }
- else if (bundle_encoding[template][slot] == B) {
- if (major_opcode == 7) {
- /* IP-Relative Predict major code is 7 */
- printk(KERN_WARNING "Kprobes on IP-Relative"
- "Predict is not supported\n");
- return -EINVAL;
- }
- else if (major_opcode == 2) {
- /* Indirect Predict, major code is 2
- * bit 27-32 to be equal to 10 or 11
- */
- int x6=(kprobe_inst >> 27) & 0x3F;
- if ((x6 == 0x10) || (x6 == 0x11)) {
- printk(KERN_WARNING "Kprobes on "
- "Indirect Predict is not supported\n");
- return -EINVAL;
- }
- }
- }
- /* kernel does not use float instruction, here for safety kprobe
- * will judge whether it is fcmp/flass/float approximation instruction
- */
- else if (unlikely(bundle_encoding[template][slot] == F)) {
- if ((major_opcode == 4 || major_opcode == 5) &&
- (kprobe_inst & (0x1 << 12))) {
- /* fcmp/fclass unc instruction */
- if (slot == 1 && qp) {
- printk(KERN_WARNING "Kprobes on fcmp/fclass "
- "instruction on slot at <0x%lx> "
- "is not supported\n", addr);
- return -EINVAL;
-
- }
- qp = 0;
- }
- if ((major_opcode == 0 || major_opcode == 1) &&
- (kprobe_inst & (0x1UL << 33))) {
- /* float Approximation instruction */
- if (slot == 1 && qp) {
- printk(KERN_WARNING "Kprobes on float Approx "
- "instr at <0x%lx> is not supported\n",
- addr);
- return -EINVAL;
- }
- qp = 0;
- }
- }
- return qp;
-}
-
-/*
- * In this function we override the bundle with
- * the break instruction at the given slot.
- */
-static void __kprobes prepare_break_inst(uint template, uint slot,
- uint major_opcode,
- unsigned long kprobe_inst,
- struct kprobe *p,
- int qp)
-{
- unsigned long break_inst = BREAK_INST;
- bundle_t *bundle = &p->opcode.bundle;
-
- /*
- * Copy the original kprobe_inst qualifying predicate(qp)
- * to the break instruction
- */
- break_inst |= qp;
-
- switch (slot) {
- case 0:
- bundle->quad0.slot0 = break_inst;
- break;
- case 1:
- bundle->quad0.slot1_p0 = break_inst;
- bundle->quad1.slot1_p1 = break_inst >> (64-46);
- break;
- case 2:
- bundle->quad1.slot2 = break_inst;
- break;
- }
-
- /*
- * Update the instruction flag, so that we can
- * emulate the instruction properly after we
- * single step on original instruction
- */
- update_kprobe_inst_flag(template, slot, major_opcode, kprobe_inst, p);
-}
-
-static void __kprobes get_kprobe_inst(bundle_t *bundle, uint slot,
- unsigned long *kprobe_inst, uint *major_opcode)
-{
- unsigned long kprobe_inst_p0, kprobe_inst_p1;
- unsigned int template;
-
- template = bundle->quad0.template;
-
- switch (slot) {
- case 0:
- *major_opcode = (bundle->quad0.slot0 >> SLOT0_OPCODE_SHIFT);
- *kprobe_inst = bundle->quad0.slot0;
- break;
- case 1:
- *major_opcode = (bundle->quad1.slot1_p1 >> SLOT1_p1_OPCODE_SHIFT);
- kprobe_inst_p0 = bundle->quad0.slot1_p0;
- kprobe_inst_p1 = bundle->quad1.slot1_p1;
- *kprobe_inst = kprobe_inst_p0 | (kprobe_inst_p1 << (64-46));
- break;
- case 2:
- *major_opcode = (bundle->quad1.slot2 >> SLOT2_OPCODE_SHIFT);
- *kprobe_inst = bundle->quad1.slot2;
- break;
- }
-}
-
-/* Returns non-zero if the addr is in the Interrupt Vector Table */
-static int __kprobes in_ivt_functions(unsigned long addr)
-{
- return (addr >= (unsigned long)__start_ivt_text
- && addr < (unsigned long)__end_ivt_text);
-}
-
-static int __kprobes valid_kprobe_addr(int template, int slot,
- unsigned long addr)
-{
- if ((slot > 2) || ((bundle_encoding[template][1] == L) && slot > 1)) {
- printk(KERN_WARNING "Attempting to insert unaligned kprobe "
- "at 0x%lx\n", addr);
- return -EINVAL;
- }
-
- if (in_ivt_functions(addr)) {
- printk(KERN_WARNING "Kprobes can't be inserted inside "
- "IVT functions at 0x%lx\n", addr);
- return -EINVAL;
- }
-
- return 0;
-}
-
-static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb)
-{
- unsigned int i;
- i = atomic_add_return(1, &kcb->prev_kprobe_index);
- kcb->prev_kprobe[i-1].kp = kprobe_running();
- kcb->prev_kprobe[i-1].status = kcb->kprobe_status;
-}
-
-static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
-{
- unsigned int i;
- i = atomic_read(&kcb->prev_kprobe_index);
- __this_cpu_write(current_kprobe, kcb->prev_kprobe[i-1].kp);
- kcb->kprobe_status = kcb->prev_kprobe[i-1].status;
- atomic_sub(1, &kcb->prev_kprobe_index);
-}
-
-static void __kprobes set_current_kprobe(struct kprobe *p,
- struct kprobe_ctlblk *kcb)
-{
- __this_cpu_write(current_kprobe, p);
-}
-
-static void kretprobe_trampoline(void)
-{
-}
-
-/*
- * At this point the target function has been tricked into
- * returning into our trampoline. Lookup the associated instance
- * and then:
- * - call the handler function
- * - cleanup by marking the instance as unused
- * - long jump back to the original return address
- */
-int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
-{
- struct kretprobe_instance *ri = NULL;
- struct hlist_head *head, empty_rp;
- struct hlist_node *tmp;
- unsigned long flags, orig_ret_address = 0;
- unsigned long trampoline_address =
- ((struct fnptr *)kretprobe_trampoline)->ip;
-
- INIT_HLIST_HEAD(&empty_rp);
- kretprobe_hash_lock(current, &head, &flags);
-
- /*
- * It is possible to have multiple instances associated with a given
- * task either because an multiple functions in the call path
- * have a return probe installed on them, and/or more than one return
- * return probe was registered for a target function.
- *
- * We can handle this because:
- * - instances are always inserted at the head of the list
- * - when multiple return probes are registered for the same
- * function, the first instance's ret_addr will point to the
- * real return address, and all the rest will point to
- * kretprobe_trampoline
- */
- hlist_for_each_entry_safe(ri, tmp, head, hlist) {
- if (ri->task != current)
- /* another task is sharing our hash bucket */
- continue;
-
- orig_ret_address = (unsigned long)ri->ret_addr;
- if (orig_ret_address != trampoline_address)
- /*
- * This is the real return address. Any other
- * instances associated with this task are for
- * other calls deeper on the call stack
- */
- break;
- }
-
- regs->cr_iip = orig_ret_address;
-
- hlist_for_each_entry_safe(ri, tmp, head, hlist) {
- if (ri->task != current)
- /* another task is sharing our hash bucket */
- continue;
-
- if (ri->rp && ri->rp->handler)
- ri->rp->handler(ri, regs);
-
- orig_ret_address = (unsigned long)ri->ret_addr;
- recycle_rp_inst(ri, &empty_rp);
-
- if (orig_ret_address != trampoline_address)
- /*
- * This is the real return address. Any other
- * instances associated with this task are for
- * other calls deeper on the call stack
- */
- break;
- }
- kretprobe_assert(ri, orig_ret_address, trampoline_address);
-
- kretprobe_hash_unlock(current, &flags);
-
- hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
- hlist_del(&ri->hlist);
- kfree(ri);
- }
- /*
- * By returning a non-zero value, we are telling
- * kprobe_handler() that we don't want the post_handler
- * to run (and have re-enabled preemption)
- */
- return 1;
-}
-
-void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
- struct pt_regs *regs)
-{
- ri->ret_addr = (kprobe_opcode_t *)regs->b0;
-
- /* Replace the return addr with trampoline addr */
- regs->b0 = ((struct fnptr *)kretprobe_trampoline)->ip;
-}
-
-/* Check the instruction in the slot is break */
-static int __kprobes __is_ia64_break_inst(bundle_t *bundle, uint slot)
-{
- unsigned int major_opcode;
- unsigned int template = bundle->quad0.template;
- unsigned long kprobe_inst;
-
- /* Move to slot 2, if bundle is MLX type and kprobe slot is 1 */
- if (slot == 1 && bundle_encoding[template][1] == L)
- slot++;
-
- /* Get Kprobe probe instruction at given slot*/
- get_kprobe_inst(bundle, slot, &kprobe_inst, &major_opcode);
-
- /* For break instruction,
- * Bits 37:40 Major opcode to be zero
- * Bits 27:32 X6 to be zero
- * Bits 32:35 X3 to be zero
- */
- if (major_opcode || ((kprobe_inst >> 27) & 0x1FF)) {
- /* Not a break instruction */
- return 0;
- }
-
- /* Is a break instruction */
- return 1;
-}
-
-/*
- * In this function, we check whether the target bundle modifies IP or
- * it triggers an exception. If so, it cannot be boostable.
- */
-static int __kprobes can_boost(bundle_t *bundle, uint slot,
- unsigned long bundle_addr)
-{
- unsigned int template = bundle->quad0.template;
-
- do {
- if (search_exception_tables(bundle_addr + slot) ||
- __is_ia64_break_inst(bundle, slot))
- return 0; /* exception may occur in this bundle*/
- } while ((++slot) < 3);
- template &= 0x1e;
- if (template >= 0x10 /* including B unit */ ||
- template == 0x04 /* including X unit */ ||
- template == 0x06) /* undefined */
- return 0;
-
- return 1;
-}
-
-/* Prepare long jump bundle and disables other boosters if need */
-static void __kprobes prepare_booster(struct kprobe *p)
-{
- unsigned long addr = (unsigned long)p->addr & ~0xFULL;
- unsigned int slot = (unsigned long)p->addr & 0xf;
- struct kprobe *other_kp;
-
- if (can_boost(&p->ainsn.insn[0].bundle, slot, addr)) {
- set_brl_inst(&p->ainsn.insn[1].bundle, (bundle_t *)addr + 1);
- p->ainsn.inst_flag |= INST_FLAG_BOOSTABLE;
- }
-
- /* disables boosters in previous slots */
- for (; addr < (unsigned long)p->addr; addr++) {
- other_kp = get_kprobe((void *)addr);
- if (other_kp)
- other_kp->ainsn.inst_flag &= ~INST_FLAG_BOOSTABLE;
- }
-}
-
-int __kprobes arch_prepare_kprobe(struct kprobe *p)
-{
- unsigned long addr = (unsigned long) p->addr;
- unsigned long *kprobe_addr = (unsigned long *)(addr & ~0xFULL);
- unsigned long kprobe_inst=0;
- unsigned int slot = addr & 0xf, template, major_opcode = 0;
- bundle_t *bundle;
- int qp;
-
- bundle = &((kprobe_opcode_t *)kprobe_addr)->bundle;
- template = bundle->quad0.template;
-
- if(valid_kprobe_addr(template, slot, addr))
- return -EINVAL;
-
- /* Move to slot 2, if bundle is MLX type and kprobe slot is 1 */
- if (slot == 1 && bundle_encoding[template][1] == L)
- slot++;
-
- /* Get kprobe_inst and major_opcode from the bundle */
- get_kprobe_inst(bundle, slot, &kprobe_inst, &major_opcode);
-
- qp = unsupported_inst(template, slot, major_opcode, kprobe_inst, addr);
- if (qp < 0)
- return -EINVAL;
-
- p->ainsn.insn = get_insn_slot();
- if (!p->ainsn.insn)
- return -ENOMEM;
- memcpy(&p->opcode, kprobe_addr, sizeof(kprobe_opcode_t));
- memcpy(p->ainsn.insn, kprobe_addr, sizeof(kprobe_opcode_t));
-
- prepare_break_inst(template, slot, major_opcode, kprobe_inst, p, qp);
-
- prepare_booster(p);
-
- return 0;
-}
-
-void __kprobes arch_arm_kprobe(struct kprobe *p)
-{
- unsigned long arm_addr;
- bundle_t *src, *dest;
-
- arm_addr = ((unsigned long)p->addr) & ~0xFUL;
- dest = &((kprobe_opcode_t *)arm_addr)->bundle;
- src = &p->opcode.bundle;
-
- flush_icache_range((unsigned long)p->ainsn.insn,
- (unsigned long)p->ainsn.insn +
- sizeof(kprobe_opcode_t) * MAX_INSN_SIZE);
-
- switch (p->ainsn.slot) {
- case 0:
- dest->quad0.slot0 = src->quad0.slot0;
- break;
- case 1:
- dest->quad1.slot1_p1 = src->quad1.slot1_p1;
- break;
- case 2:
- dest->quad1.slot2 = src->quad1.slot2;
- break;
- }
- flush_icache_range(arm_addr, arm_addr + sizeof(kprobe_opcode_t));
-}
-
-void __kprobes arch_disarm_kprobe(struct kprobe *p)
-{
- unsigned long arm_addr;
- bundle_t *src, *dest;
-
- arm_addr = ((unsigned long)p->addr) & ~0xFUL;
- dest = &((kprobe_opcode_t *)arm_addr)->bundle;
- /* p->ainsn.insn contains the original unaltered kprobe_opcode_t */
- src = &p->ainsn.insn->bundle;
- switch (p->ainsn.slot) {
- case 0:
- dest->quad0.slot0 = src->quad0.slot0;
- break;
- case 1:
- dest->quad1.slot1_p1 = src->quad1.slot1_p1;
- break;
- case 2:
- dest->quad1.slot2 = src->quad1.slot2;
- break;
- }
- flush_icache_range(arm_addr, arm_addr + sizeof(kprobe_opcode_t));
-}
-
-void __kprobes arch_remove_kprobe(struct kprobe *p)
-{
- if (p->ainsn.insn) {
- free_insn_slot(p->ainsn.insn,
- p->ainsn.inst_flag & INST_FLAG_BOOSTABLE);
- p->ainsn.insn = NULL;
- }
-}
-/*
- * We are resuming execution after a single step fault, so the pt_regs
- * structure reflects the register state after we executed the instruction
- * located in the kprobe (p->ainsn.insn->bundle). We still need to adjust
- * the ip to point back to the original stack address. To set the IP address
- * to original stack address, handle the case where we need to fixup the
- * relative IP address and/or fixup branch register.
- */
-static void __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs)
-{
- unsigned long bundle_addr = (unsigned long) (&p->ainsn.insn->bundle);
- unsigned long resume_addr = (unsigned long)p->addr & ~0xFULL;
- unsigned long template;
- int slot = ((unsigned long)p->addr & 0xf);
-
- template = p->ainsn.insn->bundle.quad0.template;
-
- if (slot == 1 && bundle_encoding[template][1] == L)
- slot = 2;
-
- if (p->ainsn.inst_flag & ~INST_FLAG_BOOSTABLE) {
-
- if (p->ainsn.inst_flag & INST_FLAG_FIX_RELATIVE_IP_ADDR) {
- /* Fix relative IP address */
- regs->cr_iip = (regs->cr_iip - bundle_addr) +
- resume_addr;
- }
-
- if (p->ainsn.inst_flag & INST_FLAG_FIX_BRANCH_REG) {
- /*
- * Fix target branch register, software convention is
- * to use either b0 or b6 or b7, so just checking
- * only those registers
- */
- switch (p->ainsn.target_br_reg) {
- case 0:
- if ((regs->b0 == bundle_addr) ||
- (regs->b0 == bundle_addr + 0x10)) {
- regs->b0 = (regs->b0 - bundle_addr) +
- resume_addr;
- }
- break;
- case 6:
- if ((regs->b6 == bundle_addr) ||
- (regs->b6 == bundle_addr + 0x10)) {
- regs->b6 = (regs->b6 - bundle_addr) +
- resume_addr;
- }
- break;
- case 7:
- if ((regs->b7 == bundle_addr) ||
- (regs->b7 == bundle_addr + 0x10)) {
- regs->b7 = (regs->b7 - bundle_addr) +
- resume_addr;
- }
- break;
- } /* end switch */
- }
- goto turn_ss_off;
- }
-
- if (slot == 2) {
- if (regs->cr_iip == bundle_addr + 0x10) {
- regs->cr_iip = resume_addr + 0x10;
- }
- } else {
- if (regs->cr_iip == bundle_addr) {
- regs->cr_iip = resume_addr;
- }
- }
-
-turn_ss_off:
- /* Turn off Single Step bit */
- ia64_psr(regs)->ss = 0;
-}
-
-static void __kprobes prepare_ss(struct kprobe *p, struct pt_regs *regs)
-{
- unsigned long bundle_addr = (unsigned long) &p->ainsn.insn->bundle;
- unsigned long slot = (unsigned long)p->addr & 0xf;
-
- /* single step inline if break instruction */
- if (p->ainsn.inst_flag == INST_FLAG_BREAK_INST)
- regs->cr_iip = (unsigned long)p->addr & ~0xFULL;
- else
- regs->cr_iip = bundle_addr & ~0xFULL;
-
- if (slot > 2)
- slot = 0;
-
- ia64_psr(regs)->ri = slot;
-
- /* turn on single stepping */
- ia64_psr(regs)->ss = 1;
-}
-
-static int __kprobes is_ia64_break_inst(struct pt_regs *regs)
-{
- unsigned int slot = ia64_psr(regs)->ri;
- unsigned long *kprobe_addr = (unsigned long *)regs->cr_iip;
- bundle_t bundle;
-
- memcpy(&bundle, kprobe_addr, sizeof(bundle_t));
-
- return __is_ia64_break_inst(&bundle, slot);
-}
-
-static int __kprobes pre_kprobes_handler(struct die_args *args)
-{
- struct kprobe *p;
- int ret = 0;
- struct pt_regs *regs = args->regs;
- kprobe_opcode_t *addr = (kprobe_opcode_t *)instruction_pointer(regs);
- struct kprobe_ctlblk *kcb;
-
- /*
- * We don't want to be preempted for the entire
- * duration of kprobe processing
- */
- preempt_disable();
- kcb = get_kprobe_ctlblk();
-
- /* Handle recursion cases */
- if (kprobe_running()) {
- p = get_kprobe(addr);
- if (p) {
- if ((kcb->kprobe_status == KPROBE_HIT_SS) &&
- (p->ainsn.inst_flag == INST_FLAG_BREAK_INST)) {
- ia64_psr(regs)->ss = 0;
- goto no_kprobe;
- }
- /* We have reentered the pre_kprobe_handler(), since
- * another probe was hit while within the handler.
- * We here save the original kprobes variables and
- * just single step on the instruction of the new probe
- * without calling any user handlers.
- */
- save_previous_kprobe(kcb);
- set_current_kprobe(p, kcb);
- kprobes_inc_nmissed_count(p);
- prepare_ss(p, regs);
- kcb->kprobe_status = KPROBE_REENTER;
- return 1;
- } else if (!is_ia64_break_inst(regs)) {
- /* The breakpoint instruction was removed by
- * another cpu right after we hit, no further
- * handling of this interrupt is appropriate
- */
- ret = 1;
- goto no_kprobe;
- } else {
- /* Not our break */
- goto no_kprobe;
- }
- }
-
- p = get_kprobe(addr);
- if (!p) {
- if (!is_ia64_break_inst(regs)) {
- /*
- * 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 our break, let kernel handle it */
- goto no_kprobe;
- }
-
- set_current_kprobe(p, kcb);
- kcb->kprobe_status = KPROBE_HIT_ACTIVE;
-
- if (p->pre_handler && p->pre_handler(p, regs)) {
- reset_current_kprobe();
- preempt_enable_no_resched();
- return 1;
- }
-
-#if !defined(CONFIG_PREEMPT)
- if (p->ainsn.inst_flag == INST_FLAG_BOOSTABLE && !p->post_handler) {
- /* Boost up -- we can execute copied instructions directly */
- ia64_psr(regs)->ri = p->ainsn.slot;
- regs->cr_iip = (unsigned long)&p->ainsn.insn->bundle & ~0xFULL;
- /* turn single stepping off */
- ia64_psr(regs)->ss = 0;
-
- reset_current_kprobe();
- preempt_enable_no_resched();
- return 1;
- }
-#endif
- prepare_ss(p, regs);
- kcb->kprobe_status = KPROBE_HIT_SS;
- return 1;
-
-no_kprobe:
- preempt_enable_no_resched();
- return ret;
-}
-
-static int __kprobes post_kprobes_handler(struct pt_regs *regs)
-{
- struct kprobe *cur = kprobe_running();
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
- if (!cur)
- return 0;
-
- if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
- kcb->kprobe_status = KPROBE_HIT_SSDONE;
- cur->post_handler(cur, regs, 0);
- }
-
- resume_execution(cur, regs);
-
- /*Restore back the original saved kprobes variables and continue. */
- if (kcb->kprobe_status == KPROBE_REENTER) {
- restore_previous_kprobe(kcb);
- goto out;
- }
- reset_current_kprobe();
-
-out:
- preempt_enable_no_resched();
- return 1;
-}
-
-int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
-{
- struct kprobe *cur = kprobe_running();
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-
- switch(kcb->kprobe_status) {
- case KPROBE_HIT_SS:
- case KPROBE_REENTER:
- /*
- * We are here because the instruction being single
- * stepped caused a page fault. We reset the current
- * kprobe and the instruction pointer points back to
- * the probe address and allow the page fault handler
- * to continue as a normal page fault.
- */
- regs->cr_iip = ((unsigned long)cur->addr) & ~0xFULL;
- ia64_psr(regs)->ri = ((unsigned long)cur->addr) & 0xf;
- if (kcb->kprobe_status == KPROBE_REENTER)
- restore_previous_kprobe(kcb);
- else
- reset_current_kprobe();
- preempt_enable_no_resched();
- break;
- case KPROBE_HIT_ACTIVE:
- case KPROBE_HIT_SSDONE:
- /*
- * We increment the nmissed count for accounting,
- * we can also use npre/npostfault count for accounting
- * these specific fault cases.
- */
- kprobes_inc_nmissed_count(cur);
-
- /*
- * We come here because instructions in the pre/post
- * handler caused the page_fault, this could happen
- * if handler tries to access user space by
- * copy_from_user(), get_user() etc. Let the
- * user-specified handler try to fix it first.
- */
- if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
- return 1;
- /*
- * In case the user-specified fault handler returned
- * zero, try to fix up.
- */
- if (ia64_done_with_exception(regs))
- return 1;
-
- /*
- * Let ia64_do_page_fault() fix it.
- */
- break;
- default:
- break;
- }
-
- return 0;
-}
-
-int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
- unsigned long val, void *data)
-{
- struct die_args *args = (struct die_args *)data;
- int ret = NOTIFY_DONE;
-
- if (args->regs && user_mode(args->regs))
- return ret;
-
- switch(val) {
- case DIE_BREAK:
- /* err is break number from ia64_bad_break() */
- if ((args->err >> 12) == (__IA64_BREAK_KPROBE >> 12)
- || args->err == 0)
- if (pre_kprobes_handler(args))
- ret = NOTIFY_STOP;
- break;
- case DIE_FAULT:
- /* err is vector number from ia64_fault() */
- if (args->err == 36)
- if (post_kprobes_handler(args->regs))
- ret = NOTIFY_STOP;
- break;
- default:
- break;
- }
- return ret;
-}
-
-unsigned long arch_deref_entry_point(void *entry)
-{
- return ((struct fnptr *)entry)->ip;
-}
-
-static struct kprobe trampoline_p = {
- .pre_handler = trampoline_probe_handler
-};
-
-int __init arch_init_kprobes(void)
-{
- trampoline_p.addr =
- (kprobe_opcode_t *)((struct fnptr *)kretprobe_trampoline)->ip;
- return register_kprobe(&trampoline_p);
-}
-
-int __kprobes arch_trampoline_kprobe(struct kprobe *p)
-{
- if (p->addr ==
- (kprobe_opcode_t *)((struct fnptr *)kretprobe_trampoline)->ip)
- return 1;
-
- return 0;
-}