#define OPCODE1(insn) ((insn)->opcode.bytes[0])
#define OPCODE2(insn) ((insn)->opcode.bytes[1])
#define OPCODE3(insn) ((insn)->opcode.bytes[2])
-#define MODRM_REG(insn) X86_MODRM_REG(insn->modrm.value)
+#define MODRM_REG(insn) X86_MODRM_REG((insn)->modrm.value)
#define W(row, b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, ba, bb, bc, bd, be, bf)\
(((b0##UL << 0x0)|(b1##UL << 0x1)|(b2##UL << 0x2)|(b3##UL << 0x3) | \
return -ENOTSUPP;
}
-/*
- * Figure out which fixups arch_uprobe_post_xol() will need to perform, and
- * annotate arch_uprobe->fixups accordingly. To start with,
- * arch_uprobe->fixups is either zero or it reflects rip-related fixups.
- */
-static void prepare_fixups(struct arch_uprobe *auprobe, struct insn *insn)
-{
- bool fix_ip = true, fix_call = false; /* defaults */
- int reg;
-
- insn_get_opcode(insn); /* should be a nop */
-
- switch (OPCODE1(insn)) {
- case 0x9d:
- /* popf */
- auprobe->fixups |= UPROBE_FIX_SETF;
- break;
- case 0xc3: /* ret/lret */
- case 0xcb:
- case 0xc2:
- case 0xca:
- /* ip is correct */
- fix_ip = false;
- break;
- case 0xe8: /* call relative - Fix return addr */
- fix_call = true;
- break;
- case 0x9a: /* call absolute - Fix return addr, not ip */
- fix_call = true;
- fix_ip = false;
- break;
- case 0xff:
- insn_get_modrm(insn);
- reg = MODRM_REG(insn);
- if (reg == 2 || reg == 3) {
- /* call or lcall, indirect */
- /* Fix return addr; ip is correct. */
- fix_call = true;
- fix_ip = false;
- } else if (reg == 4 || reg == 5) {
- /* jmp or ljmp, indirect */
- /* ip is correct. */
- fix_ip = false;
- }
- break;
- case 0xea: /* jmp absolute -- ip is correct */
- fix_ip = false;
- break;
- default:
- break;
- }
- if (fix_ip)
- auprobe->fixups |= UPROBE_FIX_IP;
- if (fix_call)
- auprobe->fixups |= UPROBE_FIX_CALL;
-}
-
#ifdef CONFIG_X86_64
/*
* If arch_uprobe->insn doesn't use rip-relative addressing, return
* - The displacement is always 4 bytes.
*/
static void
-handle_riprel_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, struct insn *insn)
+handle_riprel_insn(struct arch_uprobe *auprobe, struct insn *insn)
{
u8 *cursor;
u8 reg;
- if (mm->context.ia32_compat)
- return;
-
- auprobe->rip_rela_target_address = 0x0;
if (!insn_rip_relative(insn))
return;
cursor++;
memmove(cursor, cursor + insn->displacement.nbytes, insn->immediate.nbytes);
}
- return;
+}
+
+/*
+ * If we're emulating a rip-relative instruction, save the contents
+ * of the scratch register and store the target address in that register.
+ */
+static void
+pre_xol_rip_insn(struct arch_uprobe *auprobe, struct pt_regs *regs,
+ struct arch_uprobe_task *autask)
+{
+ if (auprobe->fixups & UPROBE_FIX_RIP_AX) {
+ autask->saved_scratch_register = regs->ax;
+ regs->ax = current->utask->vaddr;
+ regs->ax += auprobe->rip_rela_target_address;
+ } else if (auprobe->fixups & UPROBE_FIX_RIP_CX) {
+ autask->saved_scratch_register = regs->cx;
+ regs->cx = current->utask->vaddr;
+ regs->cx += auprobe->rip_rela_target_address;
+ }
+}
+
+static void
+handle_riprel_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs, long *correction)
+{
+ if (auprobe->fixups & (UPROBE_FIX_RIP_AX | UPROBE_FIX_RIP_CX)) {
+ struct arch_uprobe_task *autask;
+
+ autask = ¤t->utask->autask;
+ if (auprobe->fixups & UPROBE_FIX_RIP_AX)
+ regs->ax = autask->saved_scratch_register;
+ else
+ regs->cx = autask->saved_scratch_register;
+
+ /*
+ * The original instruction includes a displacement, and so
+ * is 4 bytes longer than what we've just single-stepped.
+ * Caller may need to apply other fixups to handle stuff
+ * like "jmpq *...(%rip)" and "callq *...(%rip)".
+ */
+ if (correction)
+ *correction += 4;
+ }
}
static int validate_insn_64bits(struct arch_uprobe *auprobe, struct insn *insn)
return validate_insn_64bits(auprobe, insn);
}
#else /* 32-bit: */
-static void handle_riprel_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, struct insn *insn)
-{
- /* No RIP-relative addressing on 32-bit */
-}
-
-static int validate_insn_bits(struct arch_uprobe *auprobe, struct mm_struct *mm, struct insn *insn)
-{
- return validate_insn_32bits(auprobe, insn);
-}
-#endif /* CONFIG_X86_64 */
-
-/**
- * arch_uprobe_analyze_insn - instruction analysis including validity and fixups.
- * @mm: the probed address space.
- * @arch_uprobe: the probepoint information.
- * @addr: virtual address at which to install the probepoint
- * Return 0 on success or a -ve number on error.
+/*
+ * No RIP-relative addressing on 32-bit
*/
-int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long addr)
+static void handle_riprel_insn(struct arch_uprobe *auprobe, struct insn *insn)
{
- int ret;
- struct insn insn;
-
- auprobe->fixups = 0;
- ret = validate_insn_bits(auprobe, mm, &insn);
- if (ret != 0)
- return ret;
-
- handle_riprel_insn(auprobe, mm, &insn);
- prepare_fixups(auprobe, &insn);
-
- return 0;
}
-
-#ifdef CONFIG_X86_64
-/*
- * If we're emulating a rip-relative instruction, save the contents
- * of the scratch register and store the target address in that register.
- */
-static void
-pre_xol_rip_insn(struct arch_uprobe *auprobe, struct pt_regs *regs,
+static void pre_xol_rip_insn(struct arch_uprobe *auprobe, struct pt_regs *regs,
struct arch_uprobe_task *autask)
{
- if (auprobe->fixups & UPROBE_FIX_RIP_AX) {
- autask->saved_scratch_register = regs->ax;
- regs->ax = current->utask->vaddr;
- regs->ax += auprobe->rip_rela_target_address;
- } else if (auprobe->fixups & UPROBE_FIX_RIP_CX) {
- autask->saved_scratch_register = regs->cx;
- regs->cx = current->utask->vaddr;
- regs->cx += auprobe->rip_rela_target_address;
- }
}
-#else
-static void
-pre_xol_rip_insn(struct arch_uprobe *auprobe, struct pt_regs *regs,
- struct arch_uprobe_task *autask)
+static void handle_riprel_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs,
+ long *correction)
{
- /* No RIP-relative addressing on 32-bit */
}
-#endif
-/*
- * arch_uprobe_pre_xol - prepare to execute out of line.
- * @auprobe: the probepoint information.
- * @regs: reflects the saved user state of current task.
- */
-int arch_uprobe_pre_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
+static int validate_insn_bits(struct arch_uprobe *auprobe, struct mm_struct *mm, struct insn *insn)
{
- struct arch_uprobe_task *autask;
-
- autask = ¤t->utask->autask;
- autask->saved_trap_nr = current->thread.trap_nr;
- current->thread.trap_nr = UPROBE_TRAP_NR;
- regs->ip = current->utask->xol_vaddr;
- pre_xol_rip_insn(auprobe, regs, autask);
+ return validate_insn_32bits(auprobe, insn);
+}
+#endif /* CONFIG_X86_64 */
- autask->saved_tf = !!(regs->flags & X86_EFLAGS_TF);
- regs->flags |= X86_EFLAGS_TF;
- if (test_tsk_thread_flag(current, TIF_BLOCKSTEP))
- set_task_blockstep(current, false);
+struct uprobe_xol_ops {
+ bool (*emulate)(struct arch_uprobe *, struct pt_regs *);
+ int (*pre_xol)(struct arch_uprobe *, struct pt_regs *);
+ int (*post_xol)(struct arch_uprobe *, struct pt_regs *);
+};
+static int default_pre_xol_op(struct arch_uprobe *auprobe, struct pt_regs *regs)
+{
+ pre_xol_rip_insn(auprobe, regs, ¤t->utask->autask);
return 0;
}
/*
- * This function is called by arch_uprobe_post_xol() to adjust the return
- * address pushed by a call instruction executed out of line.
+ * Adjust the return address pushed by a call insn executed out of line.
*/
static int adjust_ret_addr(unsigned long sp, long correction)
{
return 0;
}
-#ifdef CONFIG_X86_64
-static bool is_riprel_insn(struct arch_uprobe *auprobe)
+static int default_post_xol_op(struct arch_uprobe *auprobe, struct pt_regs *regs)
{
- return ((auprobe->fixups & (UPROBE_FIX_RIP_AX | UPROBE_FIX_RIP_CX)) != 0);
+ struct uprobe_task *utask = current->utask;
+ long correction = (long)(utask->vaddr - utask->xol_vaddr);
+ int ret = 0;
+
+ handle_riprel_post_xol(auprobe, regs, &correction);
+ if (auprobe->fixups & UPROBE_FIX_IP)
+ regs->ip += correction;
+
+ if (auprobe->fixups & UPROBE_FIX_CALL)
+ ret = adjust_ret_addr(regs->sp, correction);
+
+ return ret;
}
-static void
-handle_riprel_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs, long *correction)
+static struct uprobe_xol_ops default_xol_ops = {
+ .pre_xol = default_pre_xol_op,
+ .post_xol = default_post_xol_op,
+};
+
+/**
+ * arch_uprobe_analyze_insn - instruction analysis including validity and fixups.
+ * @mm: the probed address space.
+ * @arch_uprobe: the probepoint information.
+ * @addr: virtual address at which to install the probepoint
+ * Return 0 on success or a -ve number on error.
+ */
+int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long addr)
{
- if (is_riprel_insn(auprobe)) {
- struct arch_uprobe_task *autask;
+ struct insn insn;
+ bool fix_ip = true, fix_call = false;
+ int ret;
- autask = ¤t->utask->autask;
- if (auprobe->fixups & UPROBE_FIX_RIP_AX)
- regs->ax = autask->saved_scratch_register;
- else
- regs->cx = autask->saved_scratch_register;
+ ret = validate_insn_bits(auprobe, mm, &insn);
+ if (ret)
+ return ret;
- /*
- * The original instruction includes a displacement, and so
- * is 4 bytes longer than what we've just single-stepped.
- * Fall through to handle stuff like "jmpq *...(%rip)" and
- * "callq *...(%rip)".
- */
- if (correction)
- *correction += 4;
+ /*
+ * Figure out which fixups arch_uprobe_post_xol() will need to perform,
+ * and annotate arch_uprobe->fixups accordingly. To start with, ->fixups
+ * is either zero or it reflects rip-related fixups.
+ */
+ handle_riprel_insn(auprobe, &insn);
+
+ switch (OPCODE1(&insn)) {
+ case 0x9d: /* popf */
+ auprobe->fixups |= UPROBE_FIX_SETF;
+ break;
+ case 0xc3: /* ret or lret -- ip is correct */
+ case 0xcb:
+ case 0xc2:
+ case 0xca:
+ fix_ip = false;
+ break;
+ case 0xe8: /* call relative - Fix return addr */
+ fix_call = true;
+ break;
+ case 0x9a: /* call absolute - Fix return addr, not ip */
+ fix_call = true;
+ fix_ip = false;
+ break;
+ case 0xea: /* jmp absolute -- ip is correct */
+ fix_ip = false;
+ break;
+ case 0xff:
+ insn_get_modrm(&insn);
+ switch (MODRM_REG(&insn)) {
+ case 2: case 3: /* call or lcall, indirect */
+ fix_call = true;
+ case 4: case 5: /* jmp or ljmp, indirect */
+ fix_ip = false;
+ }
+ break;
+ default:
+ break;
}
+
+ if (fix_ip)
+ auprobe->fixups |= UPROBE_FIX_IP;
+ if (fix_call)
+ auprobe->fixups |= UPROBE_FIX_CALL;
+
+ auprobe->ops = &default_xol_ops;
+ return 0;
}
-#else
-static void
-handle_riprel_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs, long *correction)
+
+/*
+ * arch_uprobe_pre_xol - prepare to execute out of line.
+ * @auprobe: the probepoint information.
+ * @regs: reflects the saved user state of current task.
+ */
+int arch_uprobe_pre_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
{
- /* No RIP-relative addressing on 32-bit */
+ struct uprobe_task *utask = current->utask;
+
+ regs->ip = utask->xol_vaddr;
+ utask->autask.saved_trap_nr = current->thread.trap_nr;
+ current->thread.trap_nr = UPROBE_TRAP_NR;
+
+ utask->autask.saved_tf = !!(regs->flags & X86_EFLAGS_TF);
+ regs->flags |= X86_EFLAGS_TF;
+ if (test_tsk_thread_flag(current, TIF_BLOCKSTEP))
+ set_task_blockstep(current, false);
+
+ if (auprobe->ops->pre_xol)
+ return auprobe->ops->pre_xol(auprobe, regs);
+ return 0;
}
-#endif
/*
* If xol insn itself traps and generates a signal(Say,
*/
int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
{
- struct uprobe_task *utask;
- long correction;
- int result = 0;
+ struct uprobe_task *utask = current->utask;
WARN_ON_ONCE(current->thread.trap_nr != UPROBE_TRAP_NR);
-
- utask = current->utask;
current->thread.trap_nr = utask->autask.saved_trap_nr;
- correction = (long)(utask->vaddr - utask->xol_vaddr);
- handle_riprel_post_xol(auprobe, regs, &correction);
- if (auprobe->fixups & UPROBE_FIX_IP)
- regs->ip += correction;
-
- if (auprobe->fixups & UPROBE_FIX_CALL)
- result = adjust_ret_addr(regs->sp, correction);
-
/*
* arch_uprobe_pre_xol() doesn't save the state of TIF_BLOCKSTEP
* so we can get an extra SIGTRAP if we do not clear TF. We need
else if (!(auprobe->fixups & UPROBE_FIX_SETF))
regs->flags &= ~X86_EFLAGS_TF;
- return result;
+ if (auprobe->ops->post_xol)
+ return auprobe->ops->post_xol(auprobe, regs);
+ return 0;
}
/* callback routine for handling exceptions. */
{
int i;
+ if (auprobe->ops->emulate)
+ return auprobe->ops->emulate(auprobe, regs);
+
+ /* TODO: move this code into ->emulate() hook */
for (i = 0; i < MAX_UINSN_BYTES; i++) {
if (auprobe->insn[i] == 0x66)
continue;
projects / linux-2.6-microblaze.git / blobdiff