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-rw-r--r--arch/ia64/kernel/ptrace.c2012
1 files changed, 2012 insertions, 0 deletions
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c
new file mode 100644
index 0000000000..4c41912c55
--- /dev/null
+++ b/arch/ia64/kernel/ptrace.c
@@ -0,0 +1,2012 @@
+// 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/resume_user_mode.h>
+
+#include <asm/processor.h>
+#include <asm/ptrace_offsets.h>
+#include <asm/rse.h>
+#include <linux/uaccess.h>
+#include <asm/unwind.h>
+
+#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);
+}
+
+/*
+ * 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_elf_reg(struct task_struct *target, struct unw_frame_info *info,
+ 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(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_elf_reg(child, &info, ELF_CR_IPSR_OFFSET, &psr, 0) < 0 ||
+ access_elf_reg(child, &info, ELF_AR_EC_OFFSET, &ec, 0) < 0 ||
+ access_elf_reg(child, &info, ELF_AR_LC_OFFSET, &lc, 0) < 0 ||
+ access_elf_reg(child, &info, ELF_AR_RNAT_OFFSET, &rnat, 0) < 0 ||
+ access_elf_reg(child, &info, ELF_AR_BSP_OFFSET, &bsp, 0) < 0 ||
+ access_elf_reg(child, &info, ELF_CFM_OFFSET, &cfm, 0) < 0 ||
+ access_elf_reg(child, &info, ELF_NAT_OFFSET, &nat_bits, 0) < 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 retval = 0;
+ int i;
+
+ memset(&fpval, 0, sizeof(fpval));
+
+ if (!access_ok(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_elf_reg(child, &info, ELF_CR_IPSR_OFFSET, &psr, 1);
+ retval |= access_elf_reg(child, &info, ELF_AR_RSC_OFFSET, &rsc, 1);
+ retval |= access_elf_reg(child, &info, ELF_AR_EC_OFFSET, &ec, 1);
+ retval |= access_elf_reg(child, &info, ELF_AR_LC_OFFSET, &lc, 1);
+ retval |= access_elf_reg(child, &info, ELF_AR_RNAT_OFFSET, &rnat, 1);
+ retval |= access_elf_reg(child, &info, ELF_AR_BSP_OFFSET, &bsp, 1);
+ retval |= access_elf_reg(child, &info, ELF_CFM_OFFSET, &cfm, 1);
+ retval |= access_elf_reg(child, &info, ELF_NAT_OFFSET, &nat_bits, 1);
+
+ return retval ? -EIO : 0;
+}
+
+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);
+}
+
+static int
+access_uarea (struct task_struct *child, unsigned long addr,
+ unsigned long *data, int write_access);
+
+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 (ptrace_report_syscall_entry(&regs))
+ 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(&regs);
+
+ step = test_thread_flag(TIF_SINGLESTEP);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ ptrace_report_syscall_exit(&regs, 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 const ptrdiff_t pt_offsets[32] =
+{
+#define R(n) offsetof(struct pt_regs, r##n)
+ [0] = -1, R(1), R(2), R(3),
+ [4] = -1, [5] = -1, [6] = -1, [7] = -1,
+ R(8), R(9), R(10), R(11), R(12), R(13), R(14), R(15),
+ R(16), R(17), R(18), R(19), R(20), R(21), R(22), R(23),
+ R(24), R(25), R(26), R(27), R(28), R(29), R(30), R(31),
+#undef R
+};
+
+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 = task_pt_regs(target);
+ unsigned reg = addr / sizeof(unsigned long);
+ ptrdiff_t d = pt_offsets[reg];
+
+ if (d >= 0) {
+ unsigned long *ptr = (void *)pt + d;
+ if (write_access)
+ *ptr = *data;
+ else
+ *data = *ptr;
+ return 0;
+ } else {
+ char nat = 0;
+ if (write_access) {
+ /* read NaT bit first: */
+ unsigned long dummy;
+ int ret = unw_get_gr(info, reg, &dummy, &nat);
+ if (ret < 0)
+ return ret;
+ }
+ return unw_access_gr(info, reg, data, &nat, write_access);
+ }
+}
+
+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(31))
+ 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);
+}
+
+struct regset_membuf {
+ struct membuf to;
+ int ret;
+};
+
+static void do_gpregs_get(struct unw_frame_info *info, void *arg)
+{
+ struct regset_membuf *dst = arg;
+ struct membuf to = dst->to;
+ unsigned int n;
+ elf_greg_t reg;
+
+ 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 */
+ membuf_zero(&to, 8);
+ for (n = 8; to.left && n < ELF_AR_END_OFFSET; n += 8) {
+ if (access_elf_reg(info->task, info, n, &reg, 0) < 0) {
+ dst->ret = -EIO;
+ return;
+ }
+ membuf_store(&to, reg);
+ }
+}
+
+static void do_gpregs_set(struct unw_frame_info *info, void *arg)
+{
+ struct regset_getset *dst = arg;
+
+ if (unw_unwind_to_user(info) < 0)
+ return;
+
+ if (!dst->count)
+ return;
+ /* Skip r0 */
+ if (dst->pos < ELF_GR_OFFSET(1)) {
+ user_regset_copyin_ignore(&dst->pos, &dst->count,
+ &dst->u.set.kbuf, &dst->u.set.ubuf,
+ 0, ELF_GR_OFFSET(1));
+ dst->ret = 0;
+ }
+
+ while (dst->count && dst->pos < ELF_AR_END_OFFSET) {
+ unsigned int n, from, to;
+ elf_greg_t tmp[16];
+
+ from = dst->pos;
+ to = from + sizeof(tmp);
+ if (to > ELF_AR_END_OFFSET)
+ to = ELF_AR_END_OFFSET;
+ /* get up to 16 values */
+ dst->ret = user_regset_copyin(&dst->pos, &dst->count,
+ &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
+ from, to);
+ if (dst->ret)
+ return;
+ /* now copy them into registers */
+ for (n = 0; from < dst->pos; from += sizeof(elf_greg_t), n++)
+ if (access_elf_reg(dst->target, info, from,
+ &tmp[n], 1) < 0) {
+ dst->ret = -EIO;
+ return;
+ }
+ }
+}
+
+#define ELF_FP_OFFSET(i) (i * sizeof(elf_fpreg_t))
+
+static void do_fpregs_get(struct unw_frame_info *info, void *arg)
+{
+ struct task_struct *task = info->task;
+ struct regset_membuf *dst = arg;
+ struct membuf to = dst->to;
+ elf_fpreg_t reg;
+ unsigned int n;
+
+ if (unw_unwind_to_user(info) < 0)
+ return;
+
+ /* Skip pos 0 and 1 */
+ membuf_zero(&to, 2 * sizeof(elf_fpreg_t));
+
+ /* fr2-fr31 */
+ for (n = 2; to.left && n < 32; n++) {
+ if (unw_get_fr(info, n, &reg)) {
+ dst->ret = -EIO;
+ return;
+ }
+ membuf_write(&to, &reg, sizeof(reg));
+ }
+
+ /* fph */
+ if (!to.left)
+ return;
+
+ ia64_flush_fph(task);
+ if (task->thread.flags & IA64_THREAD_FPH_VALID)
+ membuf_write(&to, &task->thread.fph, 96 * sizeof(reg));
+ else
+ membuf_zero(&to, 96 * sizeof(reg));
+}
+
+static 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)) {
+ user_regset_copyin_ignore(&dst->pos, &dst->count,
+ &dst->u.set.kbuf, &dst->u.set.ubuf,
+ 0, ELF_FP_OFFSET(2));
+ dst->ret = 0;
+ if (dst->count == 0)
+ 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 void
+unwind_and_call(void (*call)(struct unw_frame_info *, void *),
+ struct task_struct *target, void *data)
+{
+ if (target == current)
+ unw_init_running(call, data);
+ else {
+ struct unw_frame_info info;
+ memset(&info, 0, sizeof(info));
+ unw_init_from_blocked_task(&info, target);
+ (*call)(&info, data);
+ }
+}
+
+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 };
+ unwind_and_call(call, target, &info);
+ return info.ret;
+}
+
+static int
+gpregs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct regset_membuf info = {.to = to};
+ unwind_and_call(do_gpregs_get, target, &info);
+ return info.ret;
+}
+
+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,
+ struct membuf to)
+{
+ struct regset_membuf info = {.to = to};
+ unwind_and_call(do_fpregs_get, target, &info);
+ return info.ret;
+}
+
+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 */
+ 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) {
+ unsigned reg = pos / sizeof(elf_fpreg_t);
+ int which_half = (pos / sizeof(unsigned long)) & 1;
+
+ if (reg < 32) { /* fr2-fr31 */
+ struct unw_frame_info info;
+ elf_fpreg_t fpreg;
+
+ memset(&info, 0, sizeof(info));
+ unw_init_from_blocked_task(&info, child);
+ if (unw_unwind_to_user(&info) < 0)
+ return 0;
+
+ if (unw_get_fr(&info, reg, &fpreg))
+ return -1;
+ if (write_access) {
+ fpreg.u.bits[which_half] = *data;
+ if (unw_set_fr(&info, reg, fpreg))
+ return -1;
+ } else {
+ *data = fpreg.u.bits[which_half];
+ }
+ } else { /* fph */
+ elf_fpreg_t *p = &child->thread.fph[reg - 32];
+ unsigned long *bits = &p->u.bits[which_half];
+
+ ia64_sync_fph(child);
+ if (write_access)
+ *bits = *data;
+ else if (child->thread.flags & IA64_THREAD_FPH_VALID)
+ *data = *bits;
+ else
+ *data = 0;
+ }
+ 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) {
+ struct unw_frame_info info;
+
+ memset(&info, 0, sizeof(info));
+ unw_init_from_blocked_task(&info, child);
+ if (unw_unwind_to_user(&info) < 0)
+ return 0;
+
+ return access_elf_reg(child, &info, pos, data, write_access);
+ }
+
+ /* 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;
+ }
+
+ 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),
+ .regset_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),
+ .regset_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_args {
+ unsigned int i;
+ unsigned int n;
+ unsigned long *args;
+ struct pt_regs *regs;
+};
+
+static void syscall_get_args_cb(struct unw_frame_info *info, void *data)
+{
+ struct syscall_get_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 arguments 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;
+ args->args[i] = *ia64_rse_skip_regs(krbs, j);
+ }
+
+ while (i < args->n) {
+ args->args[i] = 0;
+ i++;
+ }
+}
+
+void syscall_get_arguments(struct task_struct *task,
+ struct pt_regs *regs, unsigned long *args)
+{
+ struct syscall_get_args data = {
+ .i = 0,
+ .n = 6,
+ .args = args,
+ .regs = regs,
+ };
+
+ if (task == current)
+ unw_init_running(syscall_get_args_cb, &data);
+ else {
+ struct unw_frame_info ufi;
+ memset(&ufi, 0, sizeof(ufi));
+ unw_init_from_blocked_task(&ufi, task);
+ syscall_get_args_cb(&ufi, &data);
+ }
+}