diff options
Diffstat (limited to 'arch/ia64/kernel/ptrace.c')
| -rw-r--r-- | arch/ia64/kernel/ptrace.c | 2213 |
1 files changed, 2213 insertions, 0 deletions
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c new file mode 100644 index 000000000..799400287 --- /dev/null +++ b/arch/ia64/kernel/ptrace.c @@ -0,0 +1,2213 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Kernel support for the ptrace() and syscall tracing interfaces. + * + * Copyright (C) 1999-2005 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + * Copyright (C) 2006 Intel Co + * 2006-08-12 - IA64 Native Utrace implementation support added by + * Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> + * + * Derived from the x86 and Alpha versions. + */ +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/sched/task.h> +#include <linux/sched/task_stack.h> +#include <linux/mm.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/user.h> +#include <linux/security.h> +#include <linux/audit.h> +#include <linux/signal.h> +#include <linux/regset.h> +#include <linux/elf.h> +#include <linux/tracehook.h> + +#include <asm/pgtable.h> +#include <asm/processor.h> +#include <asm/ptrace_offsets.h> +#include <asm/rse.h> +#include <linux/uaccess.h> +#include <asm/unwind.h> +#ifdef CONFIG_PERFMON +#include <asm/perfmon.h> +#endif + +#include "entry.h" + +/* + * Bits in the PSR that we allow ptrace() to change: + * be, up, ac, mfl, mfh (the user mask; five bits total) + * db (debug breakpoint fault; one bit) + * id (instruction debug fault disable; one bit) + * dd (data debug fault disable; one bit) + * ri (restart instruction; two bits) + * is (instruction set; one bit) + */ +#define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS \ + | IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI) + +#define MASK(nbits) ((1UL << (nbits)) - 1) /* mask with NBITS bits set */ +#define PFM_MASK MASK(38) + +#define PTRACE_DEBUG 0 + +#if PTRACE_DEBUG +# define dprintk(format...) printk(format) +# define inline +#else +# define dprintk(format...) +#endif + +/* Return TRUE if PT was created due to kernel-entry via a system-call. */ + +static inline int +in_syscall (struct pt_regs *pt) +{ + return (long) pt->cr_ifs >= 0; +} + +/* + * Collect the NaT bits for r1-r31 from scratch_unat and return a NaT + * bitset where bit i is set iff the NaT bit of register i is set. + */ +unsigned long +ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat) +{ +# define GET_BITS(first, last, unat) \ + ({ \ + unsigned long bit = ia64_unat_pos(&pt->r##first); \ + unsigned long nbits = (last - first + 1); \ + unsigned long mask = MASK(nbits) << first; \ + unsigned long dist; \ + if (bit < first) \ + dist = 64 + bit - first; \ + else \ + dist = bit - first; \ + ia64_rotr(unat, dist) & mask; \ + }) + unsigned long val; + + /* + * Registers that are stored consecutively in struct pt_regs + * can be handled in parallel. If the register order in + * struct_pt_regs changes, this code MUST be updated. + */ + val = GET_BITS( 1, 1, scratch_unat); + val |= GET_BITS( 2, 3, scratch_unat); + val |= GET_BITS(12, 13, scratch_unat); + val |= GET_BITS(14, 14, scratch_unat); + val |= GET_BITS(15, 15, scratch_unat); + val |= GET_BITS( 8, 11, scratch_unat); + val |= GET_BITS(16, 31, scratch_unat); + return val; + +# undef GET_BITS +} + +/* + * Set the NaT bits for the scratch registers according to NAT and + * return the resulting unat (assuming the scratch registers are + * stored in PT). + */ +unsigned long +ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat) +{ +# define PUT_BITS(first, last, nat) \ + ({ \ + unsigned long bit = ia64_unat_pos(&pt->r##first); \ + unsigned long nbits = (last - first + 1); \ + unsigned long mask = MASK(nbits) << first; \ + long dist; \ + if (bit < first) \ + dist = 64 + bit - first; \ + else \ + dist = bit - first; \ + ia64_rotl(nat & mask, dist); \ + }) + unsigned long scratch_unat; + + /* + * Registers that are stored consecutively in struct pt_regs + * can be handled in parallel. If the register order in + * struct_pt_regs changes, this code MUST be updated. + */ + scratch_unat = PUT_BITS( 1, 1, nat); + scratch_unat |= PUT_BITS( 2, 3, nat); + scratch_unat |= PUT_BITS(12, 13, nat); + scratch_unat |= PUT_BITS(14, 14, nat); + scratch_unat |= PUT_BITS(15, 15, nat); + scratch_unat |= PUT_BITS( 8, 11, nat); + scratch_unat |= PUT_BITS(16, 31, nat); + + return scratch_unat; + +# undef PUT_BITS +} + +#define IA64_MLX_TEMPLATE 0x2 +#define IA64_MOVL_OPCODE 6 + +void +ia64_increment_ip (struct pt_regs *regs) +{ + unsigned long w0, ri = ia64_psr(regs)->ri + 1; + + if (ri > 2) { + ri = 0; + regs->cr_iip += 16; + } else if (ri == 2) { + get_user(w0, (char __user *) regs->cr_iip + 0); + if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) { + /* + * rfi'ing to slot 2 of an MLX bundle causes + * an illegal operation fault. We don't want + * that to happen... + */ + ri = 0; + regs->cr_iip += 16; + } + } + ia64_psr(regs)->ri = ri; +} + +void +ia64_decrement_ip (struct pt_regs *regs) +{ + unsigned long w0, ri = ia64_psr(regs)->ri - 1; + + if (ia64_psr(regs)->ri == 0) { + regs->cr_iip -= 16; + ri = 2; + get_user(w0, (char __user *) regs->cr_iip + 0); + if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) { + /* + * rfi'ing to slot 2 of an MLX bundle causes + * an illegal operation fault. We don't want + * that to happen... + */ + ri = 1; + } + } + ia64_psr(regs)->ri = ri; +} + +/* + * This routine is used to read an rnat bits that are stored on the + * kernel backing store. Since, in general, the alignment of the user + * and kernel are different, this is not completely trivial. In + * essence, we need to construct the user RNAT based on up to two + * kernel RNAT values and/or the RNAT value saved in the child's + * pt_regs. + * + * user rbs + * + * +--------+ <-- lowest address + * | slot62 | + * +--------+ + * | rnat | 0x....1f8 + * +--------+ + * | slot00 | \ + * +--------+ | + * | slot01 | > child_regs->ar_rnat + * +--------+ | + * | slot02 | / kernel rbs + * +--------+ +--------+ + * <- child_regs->ar_bspstore | slot61 | <-- krbs + * +- - - - + +--------+ + * | slot62 | + * +- - - - + +--------+ + * | rnat | + * +- - - - + +--------+ + * vrnat | slot00 | + * +- - - - + +--------+ + * = = + * +--------+ + * | slot00 | \ + * +--------+ | + * | slot01 | > child_stack->ar_rnat + * +--------+ | + * | slot02 | / + * +--------+ + * <--- child_stack->ar_bspstore + * + * The way to think of this code is as follows: bit 0 in the user rnat + * corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat + * value. The kernel rnat value holding this bit is stored in + * variable rnat0. rnat1 is loaded with the kernel rnat value that + * form the upper bits of the user rnat value. + * + * Boundary cases: + * + * o when reading the rnat "below" the first rnat slot on the kernel + * backing store, rnat0/rnat1 are set to 0 and the low order bits are + * merged in from pt->ar_rnat. + * + * o when reading the rnat "above" the last rnat slot on the kernel + * backing store, rnat0/rnat1 gets its value from sw->ar_rnat. + */ +static unsigned long +get_rnat (struct task_struct *task, struct switch_stack *sw, + unsigned long *krbs, unsigned long *urnat_addr, + unsigned long *urbs_end) +{ + unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr; + unsigned long umask = 0, mask, m; + unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift; + long num_regs, nbits; + struct pt_regs *pt; + + pt = task_pt_regs(task); + kbsp = (unsigned long *) sw->ar_bspstore; + ubspstore = (unsigned long *) pt->ar_bspstore; + + if (urbs_end < urnat_addr) + nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end); + else + nbits = 63; + mask = MASK(nbits); + /* + * First, figure out which bit number slot 0 in user-land maps + * to in the kernel rnat. Do this by figuring out how many + * register slots we're beyond the user's backingstore and + * then computing the equivalent address in kernel space. + */ + num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1); + slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs); + shift = ia64_rse_slot_num(slot0_kaddr); + rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr); + rnat0_kaddr = rnat1_kaddr - 64; + + if (ubspstore + 63 > urnat_addr) { + /* some bits need to be merged in from pt->ar_rnat */ + umask = MASK(ia64_rse_slot_num(ubspstore)) & mask; + urnat = (pt->ar_rnat & umask); + mask &= ~umask; + if (!mask) + return urnat; + } + + m = mask << shift; + if (rnat0_kaddr >= kbsp) + rnat0 = sw->ar_rnat; + else if (rnat0_kaddr > krbs) + rnat0 = *rnat0_kaddr; + urnat |= (rnat0 & m) >> shift; + + m = mask >> (63 - shift); + if (rnat1_kaddr >= kbsp) + rnat1 = sw->ar_rnat; + else if (rnat1_kaddr > krbs) + rnat1 = *rnat1_kaddr; + urnat |= (rnat1 & m) << (63 - shift); + return urnat; +} + +/* + * The reverse of get_rnat. + */ +static void +put_rnat (struct task_struct *task, struct switch_stack *sw, + unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat, + unsigned long *urbs_end) +{ + unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m; + unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift; + long num_regs, nbits; + struct pt_regs *pt; + unsigned long cfm, *urbs_kargs; + + pt = task_pt_regs(task); + kbsp = (unsigned long *) sw->ar_bspstore; + ubspstore = (unsigned long *) pt->ar_bspstore; + + urbs_kargs = urbs_end; + if (in_syscall(pt)) { + /* + * If entered via syscall, don't allow user to set rnat bits + * for syscall args. + */ + cfm = pt->cr_ifs; + urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f)); + } + + if (urbs_kargs >= urnat_addr) + nbits = 63; + else { + if ((urnat_addr - 63) >= urbs_kargs) + return; + nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs); + } + mask = MASK(nbits); + + /* + * First, figure out which bit number slot 0 in user-land maps + * to in the kernel rnat. Do this by figuring out how many + * register slots we're beyond the user's backingstore and + * then computing the equivalent address in kernel space. + */ + num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1); + slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs); + shift = ia64_rse_slot_num(slot0_kaddr); + rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr); + rnat0_kaddr = rnat1_kaddr - 64; + + if (ubspstore + 63 > urnat_addr) { + /* some bits need to be place in pt->ar_rnat: */ + umask = MASK(ia64_rse_slot_num(ubspstore)) & mask; + pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask); + mask &= ~umask; + if (!mask) + return; + } + /* + * Note: Section 11.1 of the EAS guarantees that bit 63 of an + * rnat slot is ignored. so we don't have to clear it here. + */ + rnat0 = (urnat << shift); + m = mask << shift; + if (rnat0_kaddr >= kbsp) + sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m); + else if (rnat0_kaddr > krbs) + *rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m)); + + rnat1 = (urnat >> (63 - shift)); + m = mask >> (63 - shift); + if (rnat1_kaddr >= kbsp) + sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m); + else if (rnat1_kaddr > krbs) + *rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m)); +} + +static inline int +on_kernel_rbs (unsigned long addr, unsigned long bspstore, + unsigned long urbs_end) +{ + unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *) + urbs_end); + return (addr >= bspstore && addr <= (unsigned long) rnat_addr); +} + +/* + * Read a word from the user-level backing store of task CHILD. ADDR + * is the user-level address to read the word from, VAL a pointer to + * the return value, and USER_BSP gives the end of the user-level + * backing store (i.e., it's the address that would be in ar.bsp after + * the user executed a "cover" instruction). + * + * This routine takes care of accessing the kernel register backing + * store for those registers that got spilled there. It also takes + * care of calculating the appropriate RNaT collection words. + */ +long +ia64_peek (struct task_struct *child, struct switch_stack *child_stack, + unsigned long user_rbs_end, unsigned long addr, long *val) +{ + unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr; + struct pt_regs *child_regs; + size_t copied; + long ret; + + urbs_end = (long *) user_rbs_end; + laddr = (unsigned long *) addr; + child_regs = task_pt_regs(child); + bspstore = (unsigned long *) child_regs->ar_bspstore; + krbs = (unsigned long *) child + IA64_RBS_OFFSET/8; + if (on_kernel_rbs(addr, (unsigned long) bspstore, + (unsigned long) urbs_end)) + { + /* + * Attempt to read the RBS in an area that's actually + * on the kernel RBS => read the corresponding bits in + * the kernel RBS. + */ + rnat_addr = ia64_rse_rnat_addr(laddr); + ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end); + + if (laddr == rnat_addr) { + /* return NaT collection word itself */ + *val = ret; + return 0; + } + + if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) { + /* + * It is implementation dependent whether the + * data portion of a NaT value gets saved on a + * st8.spill or RSE spill (e.g., see EAS 2.6, + * 4.4.4.6 Register Spill and Fill). To get + * consistent behavior across all possible + * IA-64 implementations, we return zero in + * this case. + */ + *val = 0; + return 0; + } + + if (laddr < urbs_end) { + /* + * The desired word is on the kernel RBS and + * is not a NaT. + */ + regnum = ia64_rse_num_regs(bspstore, laddr); + *val = *ia64_rse_skip_regs(krbs, regnum); + return 0; + } + } + copied = access_process_vm(child, addr, &ret, sizeof(ret), FOLL_FORCE); + if (copied != sizeof(ret)) + return -EIO; + *val = ret; + return 0; +} + +long +ia64_poke (struct task_struct *child, struct switch_stack *child_stack, + unsigned long user_rbs_end, unsigned long addr, long val) +{ + unsigned long *bspstore, *krbs, regnum, *laddr; + unsigned long *urbs_end = (long *) user_rbs_end; + struct pt_regs *child_regs; + + laddr = (unsigned long *) addr; + child_regs = task_pt_regs(child); + bspstore = (unsigned long *) child_regs->ar_bspstore; + krbs = (unsigned long *) child + IA64_RBS_OFFSET/8; + if (on_kernel_rbs(addr, (unsigned long) bspstore, + (unsigned long) urbs_end)) + { + /* + * Attempt to write the RBS in an area that's actually + * on the kernel RBS => write the corresponding bits + * in the kernel RBS. + */ + if (ia64_rse_is_rnat_slot(laddr)) + put_rnat(child, child_stack, krbs, laddr, val, + urbs_end); + else { + if (laddr < urbs_end) { + regnum = ia64_rse_num_regs(bspstore, laddr); + *ia64_rse_skip_regs(krbs, regnum) = val; + } + } + } else if (access_process_vm(child, addr, &val, sizeof(val), + FOLL_FORCE | FOLL_WRITE) + != sizeof(val)) + return -EIO; + return 0; +} + +/* + * Calculate the address of the end of the user-level register backing + * store. This is the address that would have been stored in ar.bsp + * if the user had executed a "cover" instruction right before + * entering the kernel. If CFMP is not NULL, it is used to return the + * "current frame mask" that was active at the time the kernel was + * entered. + */ +unsigned long +ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt, + unsigned long *cfmp) +{ + unsigned long *krbs, *bspstore, cfm = pt->cr_ifs; + long ndirty; + + krbs = (unsigned long *) child + IA64_RBS_OFFSET/8; + bspstore = (unsigned long *) pt->ar_bspstore; + ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19)); + + if (in_syscall(pt)) + ndirty += (cfm & 0x7f); + else + cfm &= ~(1UL << 63); /* clear valid bit */ + + if (cfmp) + *cfmp = cfm; + return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty); +} + +/* + * Synchronize (i.e, write) the RSE backing store living in kernel + * space to the VM of the CHILD task. SW and PT are the pointers to + * the switch_stack and pt_regs structures, respectively. + * USER_RBS_END is the user-level address at which the backing store + * ends. + */ +long +ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw, + unsigned long user_rbs_start, unsigned long user_rbs_end) +{ + unsigned long addr, val; + long ret; + + /* now copy word for word from kernel rbs to user rbs: */ + for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) { + ret = ia64_peek(child, sw, user_rbs_end, addr, &val); + if (ret < 0) + return ret; + if (access_process_vm(child, addr, &val, sizeof(val), + FOLL_FORCE | FOLL_WRITE) + != sizeof(val)) + return -EIO; + } + return 0; +} + +static long +ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw, + unsigned long user_rbs_start, unsigned long user_rbs_end) +{ + unsigned long addr, val; + long ret; + + /* now copy word for word from user rbs to kernel rbs: */ + for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) { + if (access_process_vm(child, addr, &val, sizeof(val), + FOLL_FORCE) + != sizeof(val)) + return -EIO; + + ret = ia64_poke(child, sw, user_rbs_end, addr, val); + if (ret < 0) + return ret; + } + return 0; +} + +typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *, + unsigned long, unsigned long); + +static void do_sync_rbs(struct unw_frame_info *info, void *arg) +{ + struct pt_regs *pt; + unsigned long urbs_end; + syncfunc_t fn = arg; + + if (unw_unwind_to_user(info) < 0) + return; + pt = task_pt_regs(info->task); + urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL); + + fn(info->task, info->sw, pt->ar_bspstore, urbs_end); +} + +/* + * when a thread is stopped (ptraced), debugger might change thread's user + * stack (change memory directly), and we must avoid the RSE stored in kernel + * to override user stack (user space's RSE is newer than kernel's in the + * case). To workaround the issue, we copy kernel RSE to user RSE before the + * task is stopped, so user RSE has updated data. we then copy user RSE to + * kernel after the task is resummed from traced stop and kernel will use the + * newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need + * synchronize user RSE to kernel. + */ +void ia64_ptrace_stop(void) +{ + if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE)) + return; + set_notify_resume(current); + unw_init_running(do_sync_rbs, ia64_sync_user_rbs); +} + +/* + * This is called to read back the register backing store. + */ +void ia64_sync_krbs(void) +{ + clear_tsk_thread_flag(current, TIF_RESTORE_RSE); + + unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs); +} + +/* + * After PTRACE_ATTACH, a thread's register backing store area in user + * space is assumed to contain correct data whenever the thread is + * stopped. arch_ptrace_stop takes care of this on tracing stops. + * But if the child was already stopped for job control when we attach + * to it, then it might not ever get into ptrace_stop by the time we + * want to examine the user memory containing the RBS. + */ +void +ptrace_attach_sync_user_rbs (struct task_struct *child) +{ + int stopped = 0; + struct unw_frame_info info; + + /* + * If the child is in TASK_STOPPED, we need to change that to + * TASK_TRACED momentarily while we operate on it. This ensures + * that the child won't be woken up and return to user mode while + * we are doing the sync. (It can only be woken up for SIGKILL.) + */ + + read_lock(&tasklist_lock); + if (child->sighand) { + spin_lock_irq(&child->sighand->siglock); + if (child->state == TASK_STOPPED && + !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) { + set_notify_resume(child); + + child->state = TASK_TRACED; + stopped = 1; + } + spin_unlock_irq(&child->sighand->siglock); + } + read_unlock(&tasklist_lock); + + if (!stopped) + return; + + unw_init_from_blocked_task(&info, child); + do_sync_rbs(&info, ia64_sync_user_rbs); + + /* + * Now move the child back into TASK_STOPPED if it should be in a + * job control stop, so that SIGCONT can be used to wake it up. + */ + read_lock(&tasklist_lock); + if (child->sighand) { + spin_lock_irq(&child->sighand->siglock); + if (child->state == TASK_TRACED && + (child->signal->flags & SIGNAL_STOP_STOPPED)) { + child->state = TASK_STOPPED; + } + spin_unlock_irq(&child->sighand->siglock); + } + read_unlock(&tasklist_lock); +} + +/* + * Write f32-f127 back to task->thread.fph if it has been modified. + */ +inline void +ia64_flush_fph (struct task_struct *task) +{ + struct ia64_psr *psr = ia64_psr(task_pt_regs(task)); + + /* + * Prevent migrating this task while + * we're fiddling with the FPU state + */ + preempt_disable(); + if (ia64_is_local_fpu_owner(task) && psr->mfh) { + psr->mfh = 0; + task->thread.flags |= IA64_THREAD_FPH_VALID; + ia64_save_fpu(&task->thread.fph[0]); + } + preempt_enable(); +} + +/* + * Sync the fph state of the task so that it can be manipulated + * through thread.fph. If necessary, f32-f127 are written back to + * thread.fph or, if the fph state hasn't been used before, thread.fph + * is cleared to zeroes. Also, access to f32-f127 is disabled to + * ensure that the task picks up the state from thread.fph when it + * executes again. + */ +void +ia64_sync_fph (struct task_struct *task) +{ + struct ia64_psr *psr = ia64_psr(task_pt_regs(task)); + + ia64_flush_fph(task); + if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) { + task->thread.flags |= IA64_THREAD_FPH_VALID; + memset(&task->thread.fph, 0, sizeof(task->thread.fph)); + } + ia64_drop_fpu(task); + psr->dfh = 1; +} + +/* + * Change the machine-state of CHILD such that it will return via the normal + * kernel exit-path, rather than the syscall-exit path. + */ +static void +convert_to_non_syscall (struct task_struct *child, struct pt_regs *pt, + unsigned long cfm) +{ + struct unw_frame_info info, prev_info; + unsigned long ip, sp, pr; + + unw_init_from_blocked_task(&info, child); + while (1) { + prev_info = info; + if (unw_unwind(&info) < 0) + return; + + unw_get_sp(&info, &sp); + if ((long)((unsigned long)child + IA64_STK_OFFSET - sp) + < IA64_PT_REGS_SIZE) { + dprintk("ptrace.%s: ran off the top of the kernel " + "stack\n", __func__); + return; + } + if (unw_get_pr (&prev_info, &pr) < 0) { + unw_get_rp(&prev_info, &ip); + dprintk("ptrace.%s: failed to read " + "predicate register (ip=0x%lx)\n", + __func__, ip); + return; + } + if (unw_is_intr_frame(&info) + && (pr & (1UL << PRED_USER_STACK))) + break; + } + + /* + * Note: at the time of this call, the target task is blocked + * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL + * (aka, "pLvSys") we redirect execution from + * .work_pending_syscall_end to .work_processed_kernel. + */ + unw_get_pr(&prev_info, &pr); + pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL)); + pr |= (1UL << PRED_NON_SYSCALL); + unw_set_pr(&prev_info, pr); + + pt->cr_ifs = (1UL << 63) | cfm; + /* + * Clear the memory that is NOT written on syscall-entry to + * ensure we do not leak kernel-state to user when execution + * resumes. + */ + pt->r2 = 0; + pt->r3 = 0; + pt->r14 = 0; + memset(&pt->r16, 0, 16*8); /* clear r16-r31 */ + memset(&pt->f6, 0, 6*16); /* clear f6-f11 */ + pt->b7 = 0; + pt->ar_ccv = 0; + pt->ar_csd = 0; + pt->ar_ssd = 0; +} + +static int +access_nat_bits (struct task_struct *child, struct pt_regs *pt, + struct unw_frame_info *info, + unsigned long *data, int write_access) +{ + unsigned long regnum, nat_bits, scratch_unat, dummy = 0; + char nat = 0; + + if (write_access) { + nat_bits = *data; + scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits); + if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) { + dprintk("ptrace: failed to set ar.unat\n"); + return -1; + } + for (regnum = 4; regnum <= 7; ++regnum) { + unw_get_gr(info, regnum, &dummy, &nat); + unw_set_gr(info, regnum, dummy, + (nat_bits >> regnum) & 1); + } + } else { + if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) { + dprintk("ptrace: failed to read ar.unat\n"); + return -1; + } + nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat); + for (regnum = 4; regnum <= 7; ++regnum) { + unw_get_gr(info, regnum, &dummy, &nat); + nat_bits |= (nat != 0) << regnum; + } + *data = nat_bits; + } + return 0; +} + +static int +access_uarea (struct task_struct *child, unsigned long addr, + unsigned long *data, int write_access); + +static long +ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr) +{ + unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val; + struct unw_frame_info info; + struct ia64_fpreg fpval; + struct switch_stack *sw; + struct pt_regs *pt; + long ret, retval = 0; + char nat = 0; + int i; + + if (!access_ok(VERIFY_WRITE, ppr, sizeof(struct pt_all_user_regs))) + return -EIO; + + pt = task_pt_regs(child); + sw = (struct switch_stack *) (child->thread.ksp + 16); + unw_init_from_blocked_task(&info, child); + if (unw_unwind_to_user(&info) < 0) { + return -EIO; + } + + if (((unsigned long) ppr & 0x7) != 0) { + dprintk("ptrace:unaligned register address %p\n", ppr); + return -EIO; + } + + if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0 + || access_uarea(child, PT_AR_EC, &ec, 0) < 0 + || access_uarea(child, PT_AR_LC, &lc, 0) < 0 + || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0 + || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0 + || access_uarea(child, PT_CFM, &cfm, 0) + || access_uarea(child, PT_NAT_BITS, &nat_bits, 0)) + return -EIO; + + /* control regs */ + + retval |= __put_user(pt->cr_iip, &ppr->cr_iip); + retval |= __put_user(psr, &ppr->cr_ipsr); + + /* app regs */ + + retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]); + retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]); + retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]); + retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]); + retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]); + retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]); + + retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]); + retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]); + retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]); + retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]); + retval |= __put_user(cfm, &ppr->cfm); + + /* gr1-gr3 */ + + retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long)); + retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2); + + /* gr4-gr7 */ + + for (i = 4; i < 8; i++) { + if (unw_access_gr(&info, i, &val, &nat, 0) < 0) + return -EIO; + retval |= __put_user(val, &ppr->gr[i]); + } + + /* gr8-gr11 */ + + retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4); + + /* gr12-gr15 */ + + retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2); + retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long)); + retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long)); + + /* gr16-gr31 */ + + retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16); + + /* b0 */ + + retval |= __put_user(pt->b0, &ppr->br[0]); + + /* b1-b5 */ + + for (i = 1; i < 6; i++) { + if (unw_access_br(&info, i, &val, 0) < 0) + return -EIO; + __put_user(val, &ppr->br[i]); + } + + /* b6-b7 */ + + retval |= __put_user(pt->b6, &ppr->br[6]); + retval |= __put_user(pt->b7, &ppr->br[7]); + + /* fr2-fr5 */ + + for (i = 2; i < 6; i++) { + if (unw_get_fr(&info, i, &fpval) < 0) + return -EIO; + retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval)); + } + + /* fr6-fr11 */ + + retval |= __copy_to_user(&ppr->fr[6], &pt->f6, + sizeof(struct ia64_fpreg) * 6); + + /* fp scratch regs(12-15) */ + + retval |= __copy_to_user(&ppr->fr[12], &sw->f12, + sizeof(struct ia64_fpreg) * 4); + + /* fr16-fr31 */ + + for (i = 16; i < 32; i++) { + if (unw_get_fr(&info, i, &fpval) < 0) + return -EIO; + retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval)); + } + + /* fph */ + + ia64_flush_fph(child); + retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph, + sizeof(ppr->fr[32]) * 96); + + /* preds */ + + retval |= __put_user(pt->pr, &ppr->pr); + + /* nat bits */ + + retval |= __put_user(nat_bits, &ppr->nat); + + ret = retval ? -EIO : 0; + return ret; +} + +static long +ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr) +{ + unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0; + struct unw_frame_info info; + struct switch_stack *sw; + struct ia64_fpreg fpval; + struct pt_regs *pt; + long ret, retval = 0; + int i; + + memset(&fpval, 0, sizeof(fpval)); + + if (!access_ok(VERIFY_READ, ppr, sizeof(struct pt_all_user_regs))) + return -EIO; + + pt = task_pt_regs(child); + sw = (struct switch_stack *) (child->thread.ksp + 16); + unw_init_from_blocked_task(&info, child); + if (unw_unwind_to_user(&info) < 0) { + return -EIO; + } + + if (((unsigned long) ppr & 0x7) != 0) { + dprintk("ptrace:unaligned register address %p\n", ppr); + return -EIO; + } + + /* control regs */ + + retval |= __get_user(pt->cr_iip, &ppr->cr_iip); + retval |= __get_user(psr, &ppr->cr_ipsr); + + /* app regs */ + + retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]); + retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]); + retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]); + retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]); + retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]); + retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]); + + retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]); + retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]); + retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]); + retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]); + retval |= __get_user(cfm, &ppr->cfm); + + /* gr1-gr3 */ + + retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long)); + retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2); + + /* gr4-gr7 */ + + for (i = 4; i < 8; i++) { + retval |= __get_user(val, &ppr->gr[i]); + /* NaT bit will be set via PT_NAT_BITS: */ + if (unw_set_gr(&info, i, val, 0) < 0) + return -EIO; + } + + /* gr8-gr11 */ + + retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4); + + /* gr12-gr15 */ + + retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2); + retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long)); + retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long)); + + /* gr16-gr31 */ + + retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16); + + /* b0 */ + + retval |= __get_user(pt->b0, &ppr->br[0]); + + /* b1-b5 */ + + for (i = 1; i < 6; i++) { + retval |= __get_user(val, &ppr->br[i]); + unw_set_br(&info, i, val); + } + + /* b6-b7 */ + + retval |= __get_user(pt->b6, &ppr->br[6]); + retval |= __get_user(pt->b7, &ppr->br[7]); + + /* fr2-fr5 */ + + for (i = 2; i < 6; i++) { + retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval)); + if (unw_set_fr(&info, i, fpval) < 0) + return -EIO; + } + + /* fr6-fr11 */ + + retval |= __copy_from_user(&pt->f6, &ppr->fr[6], + sizeof(ppr->fr[6]) * 6); + + /* fp scratch regs(12-15) */ + + retval |= __copy_from_user(&sw->f12, &ppr->fr[12], + sizeof(ppr->fr[12]) * 4); + + /* fr16-fr31 */ + + for (i = 16; i < 32; i++) { + retval |= __copy_from_user(&fpval, &ppr->fr[i], + sizeof(fpval)); + if (unw_set_fr(&info, i, fpval) < 0) + return -EIO; + } + + /* fph */ + + ia64_sync_fph(child); + retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32], + sizeof(ppr->fr[32]) * 96); + + /* preds */ + + retval |= __get_user(pt->pr, &ppr->pr); + + /* nat bits */ + + retval |= __get_user(nat_bits, &ppr->nat); + + retval |= access_uarea(child, PT_CR_IPSR, &psr, 1); + retval |= access_uarea(child, PT_AR_RSC, &rsc, 1); + retval |= access_uarea(child, PT_AR_EC, &ec, 1); + retval |= access_uarea(child, PT_AR_LC, &lc, 1); + retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1); + retval |= access_uarea(child, PT_AR_BSP, &bsp, 1); + retval |= access_uarea(child, PT_CFM, &cfm, 1); + retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1); + + ret = retval ? -EIO : 0; + return ret; +} + +void +user_enable_single_step (struct task_struct *child) +{ + struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child)); + + set_tsk_thread_flag(child, TIF_SINGLESTEP); + child_psr->ss = 1; +} + +void +user_enable_block_step (struct task_struct *child) +{ + struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child)); + + set_tsk_thread_flag(child, TIF_SINGLESTEP); + child_psr->tb = 1; +} + +void +user_disable_single_step (struct task_struct *child) +{ + struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child)); + + /* make sure the single step/taken-branch trap bits are not set: */ + clear_tsk_thread_flag(child, TIF_SINGLESTEP); + child_psr->ss = 0; + child_psr->tb = 0; +} + +/* + * Called by kernel/ptrace.c when detaching.. + * + * Make sure the single step bit is not set. + */ +void +ptrace_disable (struct task_struct *child) +{ + user_disable_single_step(child); +} + +long +arch_ptrace (struct task_struct *child, long request, + unsigned long addr, unsigned long data) +{ + switch (request) { + case PTRACE_PEEKTEXT: + case PTRACE_PEEKDATA: + /* read word at location addr */ + if (ptrace_access_vm(child, addr, &data, sizeof(data), + FOLL_FORCE) + != sizeof(data)) + return -EIO; + /* ensure return value is not mistaken for error code */ + force_successful_syscall_return(); + return data; + + /* PTRACE_POKETEXT and PTRACE_POKEDATA is handled + * by the generic ptrace_request(). + */ + + case PTRACE_PEEKUSR: + /* read the word at addr in the USER area */ + if (access_uarea(child, addr, &data, 0) < 0) + return -EIO; + /* ensure return value is not mistaken for error code */ + force_successful_syscall_return(); + return data; + + case PTRACE_POKEUSR: + /* write the word at addr in the USER area */ + if (access_uarea(child, addr, &data, 1) < 0) + return -EIO; + return 0; + + case PTRACE_OLD_GETSIGINFO: + /* for backwards-compatibility */ + return ptrace_request(child, PTRACE_GETSIGINFO, addr, data); + + case PTRACE_OLD_SETSIGINFO: + /* for backwards-compatibility */ + return ptrace_request(child, PTRACE_SETSIGINFO, addr, data); + + case PTRACE_GETREGS: + return ptrace_getregs(child, + (struct pt_all_user_regs __user *) data); + + case PTRACE_SETREGS: + return ptrace_setregs(child, + (struct pt_all_user_regs __user *) data); + + default: + return ptrace_request(child, request, addr, data); + } +} + + +/* "asmlinkage" so the input arguments are preserved... */ + +asmlinkage long +syscall_trace_enter (long arg0, long arg1, long arg2, long arg3, + long arg4, long arg5, long arg6, long arg7, + struct pt_regs regs) +{ + if (test_thread_flag(TIF_SYSCALL_TRACE)) + if (tracehook_report_syscall_entry(®s)) + return -ENOSYS; + + /* copy user rbs to kernel rbs */ + if (test_thread_flag(TIF_RESTORE_RSE)) + ia64_sync_krbs(); + + + audit_syscall_entry(regs.r15, arg0, arg1, arg2, arg3); + + return 0; +} + +/* "asmlinkage" so the input arguments are preserved... */ + +asmlinkage void +syscall_trace_leave (long arg0, long arg1, long arg2, long arg3, + long arg4, long arg5, long arg6, long arg7, + struct pt_regs regs) +{ + int step; + + audit_syscall_exit(®s); + + step = test_thread_flag(TIF_SINGLESTEP); + if (step || test_thread_flag(TIF_SYSCALL_TRACE)) + tracehook_report_syscall_exit(®s, step); + + /* copy user rbs to kernel rbs */ + if (test_thread_flag(TIF_RESTORE_RSE)) + ia64_sync_krbs(); +} + +/* Utrace implementation starts here */ +struct regset_get { + void *kbuf; + void __user *ubuf; +}; + +struct regset_set { + const void *kbuf; + const void __user *ubuf; +}; + +struct regset_getset { + struct task_struct *target; + const struct user_regset *regset; + union { + struct regset_get get; + struct regset_set set; + } u; + unsigned int pos; + unsigned int count; + int ret; +}; + +static int +access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info, + unsigned long addr, unsigned long *data, int write_access) +{ + struct pt_regs *pt; + unsigned long *ptr = NULL; + int ret; + char nat = 0; + + pt = task_pt_regs(target); + switch (addr) { + case ELF_GR_OFFSET(1): + ptr = &pt->r1; + break; + case ELF_GR_OFFSET(2): + case ELF_GR_OFFSET(3): + ptr = (void *)&pt->r2 + (addr - ELF_GR_OFFSET(2)); + break; + case ELF_GR_OFFSET(4) ... ELF_GR_OFFSET(7): + if (write_access) { + /* read NaT bit first: */ + unsigned long dummy; + + ret = unw_get_gr(info, addr/8, &dummy, &nat); + if (ret < 0) + return ret; + } + return unw_access_gr(info, addr/8, data, &nat, write_access); + case ELF_GR_OFFSET(8) ... ELF_GR_OFFSET(11): + ptr = (void *)&pt->r8 + addr - ELF_GR_OFFSET(8); + break; + case ELF_GR_OFFSET(12): + case ELF_GR_OFFSET(13): + ptr = (void *)&pt->r12 + addr - ELF_GR_OFFSET(12); + break; + case ELF_GR_OFFSET(14): + ptr = &pt->r14; + break; + case ELF_GR_OFFSET(15): + ptr = &pt->r15; + } + if (write_access) + *ptr = *data; + else + *data = *ptr; + return 0; +} + +static int +access_elf_breg(struct task_struct *target, struct unw_frame_info *info, + unsigned long addr, unsigned long *data, int write_access) +{ + struct pt_regs *pt; + unsigned long *ptr = NULL; + + pt = task_pt_regs(target); + switch (addr) { + case ELF_BR_OFFSET(0): + ptr = &pt->b0; + break; + case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5): + return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8, + data, write_access); + case ELF_BR_OFFSET(6): + ptr = &pt->b6; + break; + case ELF_BR_OFFSET(7): + ptr = &pt->b7; + } + if (write_access) + *ptr = *data; + else + *data = *ptr; + return 0; +} + +static int +access_elf_areg(struct task_struct *target, struct unw_frame_info *info, + unsigned long addr, unsigned long *data, int write_access) +{ + struct pt_regs *pt; + unsigned long cfm, urbs_end; + unsigned long *ptr = NULL; + + pt = task_pt_regs(target); + if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) { + switch (addr) { + case ELF_AR_RSC_OFFSET: + /* force PL3 */ + if (write_access) + pt->ar_rsc = *data | (3 << 2); + else + *data = pt->ar_rsc; + return 0; + case ELF_AR_BSP_OFFSET: + /* + * By convention, we use PT_AR_BSP to refer to + * the end of the user-level backing store. + * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof) + * to get the real value of ar.bsp at the time + * the kernel was entered. + * + * Furthermore, when changing the contents of + * PT_AR_BSP (or PT_CFM) while the task is + * blocked in a system call, convert the state + * so that the non-system-call exit + * path is used. This ensures that the proper + * state will be picked up when resuming + * execution. However, it *also* means that + * once we write PT_AR_BSP/PT_CFM, it won't be + * possible to modify the syscall arguments of + * the pending system call any longer. This + * shouldn't be an issue because modifying + * PT_AR_BSP/PT_CFM generally implies that + * we're either abandoning the pending system + * call or that we defer it's re-execution + * (e.g., due to GDB doing an inferior + * function call). + */ + urbs_end = ia64_get_user_rbs_end(target, pt, &cfm); + if (write_access) { + if (*data != urbs_end) { + if (in_syscall(pt)) + convert_to_non_syscall(target, + pt, + cfm); + /* + * Simulate user-level write + * of ar.bsp: + */ + pt->loadrs = 0; + pt->ar_bspstore = *data; + } + } else + *data = urbs_end; + return 0; + case ELF_AR_BSPSTORE_OFFSET: + ptr = &pt->ar_bspstore; + break; + case ELF_AR_RNAT_OFFSET: + ptr = &pt->ar_rnat; + break; + case ELF_AR_CCV_OFFSET: + ptr = &pt->ar_ccv; + break; + case ELF_AR_UNAT_OFFSET: + ptr = &pt->ar_unat; + break; + case ELF_AR_FPSR_OFFSET: + ptr = &pt->ar_fpsr; + break; + case ELF_AR_PFS_OFFSET: + ptr = &pt->ar_pfs; + break; + case ELF_AR_LC_OFFSET: + return unw_access_ar(info, UNW_AR_LC, data, + write_access); + case ELF_AR_EC_OFFSET: + return unw_access_ar(info, UNW_AR_EC, data, + write_access); + case ELF_AR_CSD_OFFSET: + ptr = &pt->ar_csd; + break; + case ELF_AR_SSD_OFFSET: + ptr = &pt->ar_ssd; + } + } else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) { + switch (addr) { + case ELF_CR_IIP_OFFSET: + ptr = &pt->cr_iip; + break; + case ELF_CFM_OFFSET: + urbs_end = ia64_get_user_rbs_end(target, pt, &cfm); + if (write_access) { + if (((cfm ^ *data) & PFM_MASK) != 0) { + if (in_syscall(pt)) + convert_to_non_syscall(target, + pt, + cfm); + pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK) + | (*data & PFM_MASK)); + } + } else + *data = cfm; + return 0; + case ELF_CR_IPSR_OFFSET: + if (write_access) { + unsigned long tmp = *data; + /* psr.ri==3 is a reserved value: SDM 2:25 */ + if ((tmp & IA64_PSR_RI) == IA64_PSR_RI) + tmp &= ~IA64_PSR_RI; + pt->cr_ipsr = ((tmp & IPSR_MASK) + | (pt->cr_ipsr & ~IPSR_MASK)); + } else + *data = (pt->cr_ipsr & IPSR_MASK); + return 0; + } + } else if (addr == ELF_NAT_OFFSET) + return access_nat_bits(target, pt, info, + data, write_access); + else if (addr == ELF_PR_OFFSET) + ptr = &pt->pr; + else + return -1; + + if (write_access) + *ptr = *data; + else + *data = *ptr; + + return 0; +} + +static int +access_elf_reg(struct task_struct *target, struct unw_frame_info *info, + unsigned long addr, unsigned long *data, int write_access) +{ + if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(15)) + return access_elf_gpreg(target, info, addr, data, write_access); + else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7)) + return access_elf_breg(target, info, addr, data, write_access); + else + return access_elf_areg(target, info, addr, data, write_access); +} + +void do_gpregs_get(struct unw_frame_info *info, void *arg) +{ + struct pt_regs *pt; + struct regset_getset *dst = arg; + elf_greg_t tmp[16]; + unsigned int i, index, min_copy; + + if (unw_unwind_to_user(info) < 0) + return; + + /* + * coredump format: + * r0-r31 + * NaT bits (for r0-r31; bit N == 1 iff rN is a NaT) + * predicate registers (p0-p63) + * b0-b7 + * ip cfm user-mask + * ar.rsc ar.bsp ar.bspstore ar.rnat + * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec + */ + + + /* Skip r0 */ + if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) { + dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count, + &dst->u.get.kbuf, + &dst->u.get.ubuf, + 0, ELF_GR_OFFSET(1)); + if (dst->ret || dst->count == 0) + return; + } + + /* gr1 - gr15 */ + if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) { + index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t); + min_copy = ELF_GR_OFFSET(16) > (dst->pos + dst->count) ? + (dst->pos + dst->count) : ELF_GR_OFFSET(16); + for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t), + index++) + if (access_elf_reg(dst->target, info, i, + &tmp[index], 0) < 0) { + dst->ret = -EIO; + return; + } + dst->ret = user_regset_copyout(&dst->pos, &dst->count, + &dst->u.get.kbuf, &dst->u.get.ubuf, tmp, + ELF_GR_OFFSET(1), ELF_GR_OFFSET(16)); + if (dst->ret || dst->count == 0) + return; + } + + /* r16-r31 */ + if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) { + pt = task_pt_regs(dst->target); + dst->ret = user_regset_copyout(&dst->pos, &dst->count, + &dst->u.get.kbuf, &dst->u.get.ubuf, &pt->r16, + ELF_GR_OFFSET(16), ELF_NAT_OFFSET); + if (dst->ret || dst->count == 0) + return; + } + + /* nat, pr, b0 - b7 */ + if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) { + index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t); + min_copy = ELF_CR_IIP_OFFSET > (dst->pos + dst->count) ? + (dst->pos + dst->count) : ELF_CR_IIP_OFFSET; + for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t), + index++) + if (access_elf_reg(dst->target, info, i, + &tmp[index], 0) < 0) { + dst->ret = -EIO; + return; + } + dst->ret = user_regset_copyout(&dst->pos, &dst->count, + &dst->u.get.kbuf, &dst->u.get.ubuf, tmp, + ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET); + if (dst->ret || dst->count == 0) + return; + } + + /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat + * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd + */ + if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) { + index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t); + min_copy = ELF_AR_END_OFFSET > (dst->pos + dst->count) ? + (dst->pos + dst->count) : ELF_AR_END_OFFSET; + for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t), + index++) + if (access_elf_reg(dst->target, info, i, + &tmp[index], 0) < 0) { + dst->ret = -EIO; + return; + } + dst->ret = user_regset_copyout(&dst->pos, &dst->count, + &dst->u.get.kbuf, &dst->u.get.ubuf, tmp, + ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET); + } +} + +void do_gpregs_set(struct unw_frame_info *info, void *arg) +{ + struct pt_regs *pt; + struct regset_getset *dst = arg; + elf_greg_t tmp[16]; + unsigned int i, index; + + if (unw_unwind_to_user(info) < 0) + return; + + /* Skip r0 */ + if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) { + dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count, + &dst->u.set.kbuf, + &dst->u.set.ubuf, + 0, ELF_GR_OFFSET(1)); + if (dst->ret || dst->count == 0) + return; + } + + /* gr1-gr15 */ + if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) { + i = dst->pos; + index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t); + dst->ret = user_regset_copyin(&dst->pos, &dst->count, + &dst->u.set.kbuf, &dst->u.set.ubuf, tmp, + ELF_GR_OFFSET(1), ELF_GR_OFFSET(16)); + if (dst->ret) + return; + for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++) + if (access_elf_reg(dst->target, info, i, + &tmp[index], 1) < 0) { + dst->ret = -EIO; + return; + } + if (dst->count == 0) + return; + } + + /* gr16-gr31 */ + if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) { + pt = task_pt_regs(dst->target); + dst->ret = user_regset_copyin(&dst->pos, &dst->count, + &dst->u.set.kbuf, &dst->u.set.ubuf, &pt->r16, + ELF_GR_OFFSET(16), ELF_NAT_OFFSET); + if (dst->ret || dst->count == 0) + return; + } + + /* nat, pr, b0 - b7 */ + if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) { + i = dst->pos; + index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t); + dst->ret = user_regset_copyin(&dst->pos, &dst->count, + &dst->u.set.kbuf, &dst->u.set.ubuf, tmp, + ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET); + if (dst->ret) + return; + for (; i < dst->pos; i += sizeof(elf_greg_t), index++) + if (access_elf_reg(dst->target, info, i, + &tmp[index], 1) < 0) { + dst->ret = -EIO; + return; + } + if (dst->count == 0) + return; + } + + /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat + * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd + */ + if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) { + i = dst->pos; + index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t); + dst->ret = user_regset_copyin(&dst->pos, &dst->count, + &dst->u.set.kbuf, &dst->u.set.ubuf, tmp, + ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET); + if (dst->ret) + return; + for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++) + if (access_elf_reg(dst->target, info, i, + &tmp[index], 1) < 0) { + dst->ret = -EIO; + return; + } + } +} + +#define ELF_FP_OFFSET(i) (i * sizeof(elf_fpreg_t)) + +void do_fpregs_get(struct unw_frame_info *info, void *arg) +{ + struct regset_getset *dst = arg; + struct task_struct *task = dst->target; + elf_fpreg_t tmp[30]; + int index, min_copy, i; + + if (unw_unwind_to_user(info) < 0) + return; + + /* Skip pos 0 and 1 */ + if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) { + dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count, + &dst->u.get.kbuf, + &dst->u.get.ubuf, + 0, ELF_FP_OFFSET(2)); + if (dst->count == 0 || dst->ret) + return; + } + + /* fr2-fr31 */ + if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) { + index = (dst->pos - ELF_FP_OFFSET(2)) / sizeof(elf_fpreg_t); + + min_copy = min(((unsigned int)ELF_FP_OFFSET(32)), + dst->pos + dst->count); + for (i = dst->pos; i < min_copy; i += sizeof(elf_fpreg_t), + index++) + if (unw_get_fr(info, i / sizeof(elf_fpreg_t), + &tmp[index])) { + dst->ret = -EIO; + return; + } + dst->ret = user_regset_copyout(&dst->pos, &dst->count, + &dst->u.get.kbuf, &dst->u.get.ubuf, tmp, + ELF_FP_OFFSET(2), ELF_FP_OFFSET(32)); + if (dst->count == 0 || dst->ret) + return; + } + + /* fph */ + if (dst->count > 0) { + ia64_flush_fph(dst->target); + if (task->thread.flags & IA64_THREAD_FPH_VALID) + dst->ret = user_regset_copyout( + &dst->pos, &dst->count, + &dst->u.get.kbuf, &dst->u.get.ubuf, + &dst->target->thread.fph, + ELF_FP_OFFSET(32), -1); + else + /* Zero fill instead. */ + dst->ret = user_regset_copyout_zero( + &dst->pos, &dst->count, + &dst->u.get.kbuf, &dst->u.get.ubuf, + ELF_FP_OFFSET(32), -1); + } +} + +void do_fpregs_set(struct unw_frame_info *info, void *arg) +{ + struct regset_getset *dst = arg; + elf_fpreg_t fpreg, tmp[30]; + int index, start, end; + + if (unw_unwind_to_user(info) < 0) + return; + + /* Skip pos 0 and 1 */ + if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) { + dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count, + &dst->u.set.kbuf, + &dst->u.set.ubuf, + 0, ELF_FP_OFFSET(2)); + if (dst->count == 0 || dst->ret) + return; + } + + /* fr2-fr31 */ + if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) { + start = dst->pos; + end = min(((unsigned int)ELF_FP_OFFSET(32)), + dst->pos + dst->count); + dst->ret = user_regset_copyin(&dst->pos, &dst->count, + &dst->u.set.kbuf, &dst->u.set.ubuf, tmp, + ELF_FP_OFFSET(2), ELF_FP_OFFSET(32)); + if (dst->ret) + return; + + if (start & 0xF) { /* only write high part */ + if (unw_get_fr(info, start / sizeof(elf_fpreg_t), + &fpreg)) { + dst->ret = -EIO; + return; + } + tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0] + = fpreg.u.bits[0]; + start &= ~0xFUL; + } + if (end & 0xF) { /* only write low part */ + if (unw_get_fr(info, end / sizeof(elf_fpreg_t), + &fpreg)) { + dst->ret = -EIO; + return; + } + tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1] + = fpreg.u.bits[1]; + end = (end + 0xF) & ~0xFUL; + } + + for ( ; start < end ; start += sizeof(elf_fpreg_t)) { + index = start / sizeof(elf_fpreg_t); + if (unw_set_fr(info, index, tmp[index - 2])) { + dst->ret = -EIO; + return; + } + } + if (dst->ret || dst->count == 0) + return; + } + + /* fph */ + if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) { + ia64_sync_fph(dst->target); + dst->ret = user_regset_copyin(&dst->pos, &dst->count, + &dst->u.set.kbuf, + &dst->u.set.ubuf, + &dst->target->thread.fph, + ELF_FP_OFFSET(32), -1); + } +} + +static int +do_regset_call(void (*call)(struct unw_frame_info *, void *), + struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + struct regset_getset info = { .target = target, .regset = regset, + .pos = pos, .count = count, + .u.set = { .kbuf = kbuf, .ubuf = ubuf }, + .ret = 0 }; + + if (target == current) + unw_init_running(call, &info); + else { + struct unw_frame_info ufi; + memset(&ufi, 0, sizeof(ufi)); + unw_init_from_blocked_task(&ufi, target); + (*call)(&ufi, &info); + } + + return info.ret; +} + +static int +gpregs_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + return do_regset_call(do_gpregs_get, target, regset, pos, count, + kbuf, ubuf); +} + +static int gpregs_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + return do_regset_call(do_gpregs_set, target, regset, pos, count, + kbuf, ubuf); +} + +static void do_gpregs_writeback(struct unw_frame_info *info, void *arg) +{ + do_sync_rbs(info, ia64_sync_user_rbs); +} + +/* + * This is called to write back the register backing store. + * ptrace does this before it stops, so that a tracer reading the user + * memory after the thread stops will get the current register data. + */ +static int +gpregs_writeback(struct task_struct *target, + const struct user_regset *regset, + int now) +{ + if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE)) + return 0; + set_notify_resume(target); + return do_regset_call(do_gpregs_writeback, target, regset, 0, 0, + NULL, NULL); +} + +static int +fpregs_active(struct task_struct *target, const struct user_regset *regset) +{ + return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32; +} + +static int fpregs_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + return do_regset_call(do_fpregs_get, target, regset, pos, count, + kbuf, ubuf); +} + +static int fpregs_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + return do_regset_call(do_fpregs_set, target, regset, pos, count, + kbuf, ubuf); +} + +static int +access_uarea(struct task_struct *child, unsigned long addr, + unsigned long *data, int write_access) +{ + unsigned int pos = -1; /* an invalid value */ + int ret; + unsigned long *ptr, regnum; + + if ((addr & 0x7) != 0) { + dprintk("ptrace: unaligned register address 0x%lx\n", addr); + return -1; + } + if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) || + (addr >= PT_R7 + 8 && addr < PT_B1) || + (addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) || + (addr >= PT_AR_SSD + 8 && addr < PT_DBR)) { + dprintk("ptrace: rejecting access to register " + "address 0x%lx\n", addr); + return -1; + } + + switch (addr) { + case PT_F32 ... (PT_F127 + 15): + pos = addr - PT_F32 + ELF_FP_OFFSET(32); + break; + case PT_F2 ... (PT_F5 + 15): + pos = addr - PT_F2 + ELF_FP_OFFSET(2); + break; + case PT_F10 ... (PT_F31 + 15): + pos = addr - PT_F10 + ELF_FP_OFFSET(10); + break; + case PT_F6 ... (PT_F9 + 15): + pos = addr - PT_F6 + ELF_FP_OFFSET(6); + break; + } + + if (pos != -1) { + if (write_access) + ret = fpregs_set(child, NULL, pos, + sizeof(unsigned long), data, NULL); + else + ret = fpregs_get(child, NULL, pos, + sizeof(unsigned long), data, NULL); + if (ret != 0) + return -1; + return 0; + } + + switch (addr) { + case PT_NAT_BITS: + pos = ELF_NAT_OFFSET; + break; + case PT_R4 ... PT_R7: + pos = addr - PT_R4 + ELF_GR_OFFSET(4); + break; + case PT_B1 ... PT_B5: + pos = addr - PT_B1 + ELF_BR_OFFSET(1); + break; + case PT_AR_EC: + pos = ELF_AR_EC_OFFSET; + break; + case PT_AR_LC: + pos = ELF_AR_LC_OFFSET; + break; + case PT_CR_IPSR: + pos = ELF_CR_IPSR_OFFSET; + break; + case PT_CR_IIP: + pos = ELF_CR_IIP_OFFSET; + break; + case PT_CFM: + pos = ELF_CFM_OFFSET; + break; + case PT_AR_UNAT: + pos = ELF_AR_UNAT_OFFSET; + break; + case PT_AR_PFS: + pos = ELF_AR_PFS_OFFSET; + break; + case PT_AR_RSC: + pos = ELF_AR_RSC_OFFSET; + break; + case PT_AR_RNAT: + pos = ELF_AR_RNAT_OFFSET; + break; + case PT_AR_BSPSTORE: + pos = ELF_AR_BSPSTORE_OFFSET; + break; + case PT_PR: + pos = ELF_PR_OFFSET; + break; + case PT_B6: + pos = ELF_BR_OFFSET(6); + break; + case PT_AR_BSP: + pos = ELF_AR_BSP_OFFSET; + break; + case PT_R1 ... PT_R3: + pos = addr - PT_R1 + ELF_GR_OFFSET(1); + break; + case PT_R12 ... PT_R15: + pos = addr - PT_R12 + ELF_GR_OFFSET(12); + break; + case PT_R8 ... PT_R11: + pos = addr - PT_R8 + ELF_GR_OFFSET(8); + break; + case PT_R16 ... PT_R31: + pos = addr - PT_R16 + ELF_GR_OFFSET(16); + break; + case PT_AR_CCV: + pos = ELF_AR_CCV_OFFSET; + break; + case PT_AR_FPSR: + pos = ELF_AR_FPSR_OFFSET; + break; + case PT_B0: + pos = ELF_BR_OFFSET(0); + break; + case PT_B7: + pos = ELF_BR_OFFSET(7); + break; + case PT_AR_CSD: + pos = ELF_AR_CSD_OFFSET; + break; + case PT_AR_SSD: + pos = ELF_AR_SSD_OFFSET; + break; + } + + if (pos != -1) { + if (write_access) + ret = gpregs_set(child, NULL, pos, + sizeof(unsigned long), data, NULL); + else + ret = gpregs_get(child, NULL, pos, + sizeof(unsigned long), data, NULL); + if (ret != 0) + return -1; + return 0; + } + + /* access debug registers */ + if (addr >= PT_IBR) { + regnum = (addr - PT_IBR) >> 3; + ptr = &child->thread.ibr[0]; + } else { + regnum = (addr - PT_DBR) >> 3; + ptr = &child->thread.dbr[0]; + } + + if (regnum >= 8) { + dprintk("ptrace: rejecting access to register " + "address 0x%lx\n", addr); + return -1; + } +#ifdef CONFIG_PERFMON + /* + * Check if debug registers are used by perfmon. This + * test must be done once we know that we can do the + * operation, i.e. the arguments are all valid, but + * before we start modifying the state. + * + * Perfmon needs to keep a count of how many processes + * are trying to modify the debug registers for system + * wide monitoring sessions. + * + * We also include read access here, because they may + * cause the PMU-installed debug register state + * (dbr[], ibr[]) to be reset. The two arrays are also + * used by perfmon, but we do not use + * IA64_THREAD_DBG_VALID. The registers are restored + * by the PMU context switch code. + */ + if (pfm_use_debug_registers(child)) + return -1; +#endif + + if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) { + child->thread.flags |= IA64_THREAD_DBG_VALID; + memset(child->thread.dbr, 0, + sizeof(child->thread.dbr)); + memset(child->thread.ibr, 0, + sizeof(child->thread.ibr)); + } + + ptr += regnum; + + if ((regnum & 1) && write_access) { + /* don't let the user set kernel-level breakpoints: */ + *ptr = *data & ~(7UL << 56); + return 0; + } + if (write_access) + *ptr = *data; + else + *data = *ptr; + return 0; +} + +static const struct user_regset native_regsets[] = { + { + .core_note_type = NT_PRSTATUS, + .n = ELF_NGREG, + .size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t), + .get = gpregs_get, .set = gpregs_set, + .writeback = gpregs_writeback + }, + { + .core_note_type = NT_PRFPREG, + .n = ELF_NFPREG, + .size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t), + .get = fpregs_get, .set = fpregs_set, .active = fpregs_active + }, +}; + +static const struct user_regset_view user_ia64_view = { + .name = "ia64", + .e_machine = EM_IA_64, + .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets) +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *tsk) +{ + return &user_ia64_view; +} + +struct syscall_get_set_args { + unsigned int i; + unsigned int n; + unsigned long *args; + struct pt_regs *regs; + int rw; +}; + +static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data) +{ + struct syscall_get_set_args *args = data; + struct pt_regs *pt = args->regs; + unsigned long *krbs, cfm, ndirty, nlocals, nouts; + int i, count; + + if (unw_unwind_to_user(info) < 0) + return; + + /* + * We get here via a few paths: + * - break instruction: cfm is shared with caller. + * syscall args are in out= regs, locals are non-empty. + * - epsinstruction: cfm is set by br.call + * locals don't exist. + * + * For both cases argguments are reachable in cfm.sof - cfm.sol. + * CFM: [ ... | sor: 17..14 | sol : 13..7 | sof : 6..0 ] + */ + cfm = pt->cr_ifs; + nlocals = (cfm >> 7) & 0x7f; /* aka sol */ + nouts = (cfm & 0x7f) - nlocals; /* aka sof - sol */ + krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8; + ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19)); + + count = 0; + if (in_syscall(pt)) + count = min_t(int, args->n, nouts); + + /* Iterate over outs. */ + for (i = 0; i < count; i++) { + int j = ndirty + nlocals + i + args->i; + if (args->rw) + *ia64_rse_skip_regs(krbs, j) = args->args[i]; + else + args->args[i] = *ia64_rse_skip_regs(krbs, j); + } + + if (!args->rw) { + while (i < args->n) { + args->args[i] = 0; + i++; + } + } +} + +void ia64_syscall_get_set_arguments(struct task_struct *task, + struct pt_regs *regs, unsigned int i, unsigned int n, + unsigned long *args, int rw) +{ + struct syscall_get_set_args data = { + .i = i, + .n = n, + .args = args, + .regs = regs, + .rw = rw, + }; + + if (task == current) + unw_init_running(syscall_get_set_args_cb, &data); + else { + struct unw_frame_info ufi; + memset(&ufi, 0, sizeof(ufi)); + unw_init_from_blocked_task(&ufi, task); + syscall_get_set_args_cb(&ufi, &data); + } +} |