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-rw-r--r--drivers/gpio/gpio-msm-v2.c3
-rw-r--r--drivers/gpio/gpio-mxc.c2
-rw-r--r--drivers/gpio/gpio-omap.c3
-rw-r--r--drivers/gpio/gpio-pl061.c2
-rw-r--r--drivers/gpio/gpio-pxa.c3
-rw-r--r--drivers/gpio/gpio-tegra.c3
6 files changed, 6 insertions, 10 deletions
diff --git a/drivers/gpio/gpio-msm-v2.c b/drivers/gpio/gpio-msm-v2.c
index 55a7e7769af6..dd2eddeb1e0c 100644
--- a/drivers/gpio/gpio-msm-v2.c
+++ b/drivers/gpio/gpio-msm-v2.c
@@ -23,13 +23,12 @@
23#include <linux/init.h> 23#include <linux/init.h>
24#include <linux/interrupt.h> 24#include <linux/interrupt.h>
25#include <linux/io.h> 25#include <linux/io.h>
26#include <linux/irqchip/chained_irq.h>
26#include <linux/irq.h> 27#include <linux/irq.h>
27#include <linux/module.h> 28#include <linux/module.h>
28#include <linux/platform_device.h> 29#include <linux/platform_device.h>
29#include <linux/spinlock.h> 30#include <linux/spinlock.h>
30 31
31#include <asm/mach/irq.h>
32
33#include <mach/msm_gpiomux.h> 32#include <mach/msm_gpiomux.h>
34#include <mach/msm_iomap.h> 33#include <mach/msm_iomap.h>
35 34
diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
index 7877335c4cc8..7176743915d3 100644
--- a/drivers/gpio/gpio-mxc.c
+++ b/drivers/gpio/gpio-mxc.c
@@ -24,6 +24,7 @@
24#include <linux/io.h> 24#include <linux/io.h>
25#include <linux/irq.h> 25#include <linux/irq.h>
26#include <linux/irqdomain.h> 26#include <linux/irqdomain.h>
27#include <linux/irqchip/chained_irq.h>
27#include <linux/gpio.h> 28#include <linux/gpio.h>
28#include <linux/platform_device.h> 29#include <linux/platform_device.h>
29#include <linux/slab.h> 30#include <linux/slab.h>
@@ -32,7 +33,6 @@
32#include <linux/of_device.h> 33#include <linux/of_device.h>
33#include <linux/module.h> 34#include <linux/module.h>
34#include <asm-generic/bug.h> 35#include <asm-generic/bug.h>
35#include <asm/mach/irq.h>
36 36
37enum mxc_gpio_hwtype { 37enum mxc_gpio_hwtype {
38 IMX1_GPIO, /* runs on i.mx1 */ 38 IMX1_GPIO, /* runs on i.mx1 */
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index 159f5c57eb45..a612ea1c53cb 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -25,11 +25,10 @@
25#include <linux/of.h> 25#include <linux/of.h>
26#include <linux/of_device.h> 26#include <linux/of_device.h>
27#include <linux/irqdomain.h> 27#include <linux/irqdomain.h>
28#include <linux/irqchip/chained_irq.h>
28#include <linux/gpio.h> 29#include <linux/gpio.h>
29#include <linux/platform_data/gpio-omap.h> 30#include <linux/platform_data/gpio-omap.h>
30 31
31#include <asm/mach/irq.h>
32
33#define OFF_MODE 1 32#define OFF_MODE 1
34 33
35static LIST_HEAD(omap_gpio_list); 34static LIST_HEAD(omap_gpio_list);
diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c
index b820869ca93c..29763361d13c 100644
--- a/drivers/gpio/gpio-pl061.c
+++ b/drivers/gpio/gpio-pl061.c
@@ -15,6 +15,7 @@
15#include <linux/io.h> 15#include <linux/io.h>
16#include <linux/ioport.h> 16#include <linux/ioport.h>
17#include <linux/irq.h> 17#include <linux/irq.h>
18#include <linux/irqchip/chained_irq.h>
18#include <linux/bitops.h> 19#include <linux/bitops.h>
19#include <linux/workqueue.h> 20#include <linux/workqueue.h>
20#include <linux/gpio.h> 21#include <linux/gpio.h>
@@ -23,7 +24,6 @@
23#include <linux/amba/pl061.h> 24#include <linux/amba/pl061.h>
24#include <linux/slab.h> 25#include <linux/slab.h>
25#include <linux/pm.h> 26#include <linux/pm.h>
26#include <asm/mach/irq.h>
27 27
28#define GPIODIR 0x400 28#define GPIODIR 0x400
29#define GPIOIS 0x404 29#define GPIOIS 0x404
diff --git a/drivers/gpio/gpio-pxa.c b/drivers/gpio/gpio-pxa.c
index 9cc108d2b770..7523b6d108d0 100644
--- a/drivers/gpio/gpio-pxa.c
+++ b/drivers/gpio/gpio-pxa.c
@@ -19,6 +19,7 @@
19#include <linux/init.h> 19#include <linux/init.h>
20#include <linux/irq.h> 20#include <linux/irq.h>
21#include <linux/irqdomain.h> 21#include <linux/irqdomain.h>
22#include <linux/irqchip/chained_irq.h>
22#include <linux/io.h> 23#include <linux/io.h>
23#include <linux/of.h> 24#include <linux/of.h>
24#include <linux/of_device.h> 25#include <linux/of_device.h>
@@ -26,8 +27,6 @@
26#include <linux/syscore_ops.h> 27#include <linux/syscore_ops.h>
27#include <linux/slab.h> 28#include <linux/slab.h>
28 29
29#include <asm/mach/irq.h>
30
31#include <mach/irqs.h> 30#include <mach/irqs.h>
32 31
33/* 32/*
diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c
index 414ad912232f..8e2155548888 100644
--- a/drivers/gpio/gpio-tegra.c
+++ b/drivers/gpio/gpio-tegra.c
@@ -27,11 +27,10 @@
27#include <linux/platform_device.h> 27#include <linux/platform_device.h>
28#include <linux/module.h> 28#include <linux/module.h>
29#include <linux/irqdomain.h> 29#include <linux/irqdomain.h>
30#include <linux/irqchip/chained_irq.h>
30#include <linux/pinctrl/consumer.h> 31#include <linux/pinctrl/consumer.h>
31#include <linux/pm.h> 32#include <linux/pm.h>
32 33
33#include <asm/mach/irq.h>
34
35#define GPIO_BANK(x) ((x) >> 5) 34#define GPIO_BANK(x) ((x) >> 5)
36#define GPIO_PORT(x) (((x) >> 3) & 0x3) 35#define GPIO_PORT(x) (((x) >> 3) & 0x3)
37#define GPIO_BIT(x) ((x) & 0x7) 36#define GPIO_BIT(x) ((x) & 0x7)
href='#n1142'>1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197
/*
 * linux/kernel/ptrace.c
 *
 * (C) Copyright 1999 Linus Torvalds
 *
 * Common interfaces for "ptrace()" which we do not want
 * to continually duplicate across every architecture.
 */

#include <linux/capability.h>
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/ptrace.h>
#include <linux/security.h>
#include <linux/signal.h>
#include <linux/uio.h>
#include <linux/audit.h>
#include <linux/pid_namespace.h>
#include <linux/syscalls.h>
#include <linux/uaccess.h>
#include <linux/regset.h>
#include <linux/hw_breakpoint.h>
#include <linux/cn_proc.h>
#include <linux/compat.h>


static int ptrace_trapping_sleep_fn(void *flags)
{
	schedule();
	return 0;
}

/*
 * ptrace a task: make the debugger its new parent and
 * move it to the ptrace list.
 *
 * Must be called with the tasklist lock write-held.
 */
void __ptrace_link(struct task_struct *child, struct task_struct *new_parent)
{
	BUG_ON(!list_empty(&child->ptrace_entry));
	list_add(&child->ptrace_entry, &new_parent->ptraced);
	child->parent = new_parent;
}

/**
 * __ptrace_unlink - unlink ptracee and restore its execution state
 * @child: ptracee to be unlinked
 *
 * Remove @child from the ptrace list, move it back to the original parent,
 * and restore the execution state so that it conforms to the group stop
 * state.
 *
 * Unlinking can happen via two paths - explicit PTRACE_DETACH or ptracer
 * exiting.  For PTRACE_DETACH, unless the ptracee has been killed between
 * ptrace_check_attach() and here, it's guaranteed to be in TASK_TRACED.
 * If the ptracer is exiting, the ptracee can be in any state.
 *
 * After detach, the ptracee should be in a state which conforms to the
 * group stop.  If the group is stopped or in the process of stopping, the
 * ptracee should be put into TASK_STOPPED; otherwise, it should be woken
 * up from TASK_TRACED.
 *
 * If the ptracee is in TASK_TRACED and needs to be moved to TASK_STOPPED,
 * it goes through TRACED -> RUNNING -> STOPPED transition which is similar
 * to but in the opposite direction of what happens while attaching to a
 * stopped task.  However, in this direction, the intermediate RUNNING
 * state is not hidden even from the current ptracer and if it immediately
 * re-attaches and performs a WNOHANG wait(2), it may fail.
 *
 * CONTEXT:
 * write_lock_irq(tasklist_lock)
 */
void __ptrace_unlink(struct task_struct *child)
{
	BUG_ON(!child->ptrace);

	child->ptrace = 0;
	child->parent = child->real_parent;
	list_del_init(&child->ptrace_entry);

	spin_lock(&child->sighand->siglock);

	/*
	 * Clear all pending traps and TRAPPING.  TRAPPING should be
	 * cleared regardless of JOBCTL_STOP_PENDING.  Do it explicitly.
	 */
	task_clear_jobctl_pending(child, JOBCTL_TRAP_MASK);
	task_clear_jobctl_trapping(child);

	/*
	 * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and
	 * @child isn't dead.
	 */
	if (!(child->flags & PF_EXITING) &&
	    (child->signal->flags & SIGNAL_STOP_STOPPED ||
	     child->signal->group_stop_count)) {
		child->jobctl |= JOBCTL_STOP_PENDING;

		/*
		 * This is only possible if this thread was cloned by the
		 * traced task running in the stopped group, set the signal
		 * for the future reports.
		 * FIXME: we should change ptrace_init_task() to handle this
		 * case.
		 */
		if (!(child->jobctl & JOBCTL_STOP_SIGMASK))
			child->jobctl |= SIGSTOP;
	}

	/*
	 * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick
	 * @child in the butt.  Note that @resume should be used iff @child
	 * is in TASK_TRACED; otherwise, we might unduly disrupt
	 * TASK_KILLABLE sleeps.
	 */
	if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child))
		ptrace_signal_wake_up(child, true);

	spin_unlock(&child->sighand->siglock);
}

/* Ensure that nothing can wake it up, even SIGKILL */
static bool ptrace_freeze_traced(struct task_struct *task)
{
	bool ret = false;

	/* Lockless, nobody but us can set this flag */
	if (task->jobctl & JOBCTL_LISTENING)
		return ret;

	spin_lock_irq(&task->sighand->siglock);
	if (task_is_traced(task) && !__fatal_signal_pending(task)) {
		task->state = __TASK_TRACED;
		ret = true;
	}
	spin_unlock_irq(&task->sighand->siglock);

	return ret;
}

static void ptrace_unfreeze_traced(struct task_struct *task)
{
	if (task->state != __TASK_TRACED)
		return;

	WARN_ON(!task->ptrace || task->parent != current);

	spin_lock_irq(&task->sighand->siglock);
	if (__fatal_signal_pending(task))
		wake_up_state(task, __TASK_TRACED);
	else
		task->state = TASK_TRACED;
	spin_unlock_irq(&task->sighand->siglock);
}

/**
 * ptrace_check_attach - check whether ptracee is ready for ptrace operation
 * @child: ptracee to check for
 * @ignore_state: don't check whether @child is currently %TASK_TRACED
 *
 * Check whether @child is being ptraced by %current and ready for further
 * ptrace operations.  If @ignore_state is %false, @child also should be in
 * %TASK_TRACED state and on return the child is guaranteed to be traced
 * and not executing.  If @ignore_state is %true, @child can be in any
 * state.
 *
 * CONTEXT:
 * Grabs and releases tasklist_lock and @child->sighand->siglock.
 *
 * RETURNS:
 * 0 on success, -ESRCH if %child is not ready.
 */
static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
{
	int ret = -ESRCH;

	/*
	 * We take the read lock around doing both checks to close a
	 * possible race where someone else was tracing our child and
	 * detached between these two checks.  After this locked check,
	 * we are sure that this is our traced child and that can only
	 * be changed by us so it's not changing right after this.
	 */
	read_lock(&tasklist_lock);
	if (child->ptrace && child->parent == current) {
		WARN_ON(child->state == __TASK_TRACED);
		/*
		 * child->sighand can't be NULL, release_task()
		 * does ptrace_unlink() before __exit_signal().
		 */
		if (ignore_state || ptrace_freeze_traced(child))
			ret = 0;
	}
	read_unlock(&tasklist_lock);

	if (!ret && !ignore_state) {
		if (!wait_task_inactive(child, __TASK_TRACED)) {
			/*
			 * This can only happen if may_ptrace_stop() fails and
			 * ptrace_stop() changes ->state back to TASK_RUNNING,
			 * so we should not worry about leaking __TASK_TRACED.
			 */
			WARN_ON(child->state == __TASK_TRACED);
			ret = -ESRCH;
		}
	}

	return ret;
}

static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode)
{
	if (mode & PTRACE_MODE_NOAUDIT)
		return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE);
	else
		return has_ns_capability(current, ns, CAP_SYS_PTRACE);
}

/* Returns 0 on success, -errno on denial. */
static int __ptrace_may_access(struct task_struct *task, unsigned int mode)
{
	const struct cred *cred = current_cred(), *tcred;

	/* May we inspect the given task?
	 * This check is used both for attaching with ptrace
	 * and for allowing access to sensitive information in /proc.
	 *
	 * ptrace_attach denies several cases that /proc allows
	 * because setting up the necessary parent/child relationship
	 * or halting the specified task is impossible.
	 */
	int dumpable = 0;
	/* Don't let security modules deny introspection */
	if (task == current)
		return 0;
	rcu_read_lock();
	tcred = __task_cred(task);
	if (uid_eq(cred->uid, tcred->euid) &&
	    uid_eq(cred->uid, tcred->suid) &&
	    uid_eq(cred->uid, tcred->uid)  &&
	    gid_eq(cred->gid, tcred->egid) &&
	    gid_eq(cred->gid, tcred->sgid) &&
	    gid_eq(cred->gid, tcred->gid))
		goto ok;
	if (ptrace_has_cap(tcred->user_ns, mode))
		goto ok;
	rcu_read_unlock();
	return -EPERM;
ok:
	rcu_read_unlock();
	smp_rmb();
	if (task->mm)
		dumpable = get_dumpable(task->mm);
	rcu_read_lock();
	if (!dumpable && !ptrace_has_cap(__task_cred(task)->user_ns, mode)) {
		rcu_read_unlock();
		return -EPERM;
	}
	rcu_read_unlock();

	return security_ptrace_access_check(task, mode);
}

bool ptrace_may_access(struct task_struct *task, unsigned int mode)
{
	int err;
	task_lock(task);
	err = __ptrace_may_access(task, mode);
	task_unlock(task);
	return !err;
}

static int ptrace_attach(struct task_struct *task, long request,
			 unsigned long addr,
			 unsigned long flags)
{
	bool seize = (request == PTRACE_SEIZE);
	int retval;

	retval = -EIO;
	if (seize) {
		if (addr != 0)
			goto out;
		if (flags & ~(unsigned long)PTRACE_O_MASK)
			goto out;
		flags = PT_PTRACED | PT_SEIZED | (flags << PT_OPT_FLAG_SHIFT);
	} else {
		flags = PT_PTRACED;
	}

	audit_ptrace(task);

	retval = -EPERM;
	if (unlikely(task->flags & PF_KTHREAD))
		goto out;
	if (same_thread_group(task, current))
		goto out;

	/*
	 * Protect exec's credential calculations against our interference;
	 * SUID, SGID and LSM creds get determined differently
	 * under ptrace.
	 */
	retval = -ERESTARTNOINTR;
	if (mutex_lock_interruptible(&task->signal->cred_guard_mutex))
		goto out;

	task_lock(task);
	retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH);
	task_unlock(task);
	if (retval)
		goto unlock_creds;

	write_lock_irq(&tasklist_lock);
	retval = -EPERM;
	if (unlikely(task->exit_state))
		goto unlock_tasklist;
	if (task->ptrace)
		goto unlock_tasklist;

	if (seize)
		flags |= PT_SEIZED;
	rcu_read_lock();
	if (ns_capable(__task_cred(task)->user_ns, CAP_SYS_PTRACE))
		flags |= PT_PTRACE_CAP;
	rcu_read_unlock();
	task->ptrace = flags;

	__ptrace_link(task, current);

	/* SEIZE doesn't trap tracee on attach */
	if (!seize)
		send_sig_info(SIGSTOP, SEND_SIG_FORCED, task);

	spin_lock(&task->sighand->siglock);

	/*
	 * If the task is already STOPPED, set JOBCTL_TRAP_STOP and
	 * TRAPPING, and kick it so that it transits to TRACED.  TRAPPING
	 * will be cleared if the child completes the transition or any
	 * event which clears the group stop states happens.  We'll wait
	 * for the transition to complete before returning from this
	 * function.
	 *
	 * This hides STOPPED -> RUNNING -> TRACED transition from the
	 * attaching thread but a different thread in the same group can
	 * still observe the transient RUNNING state.  IOW, if another
	 * thread's WNOHANG wait(2) on the stopped tracee races against
	 * ATTACH, the wait(2) may fail due to the transient RUNNING.
	 *
	 * The following task_is_stopped() test is safe as both transitions
	 * in and out of STOPPED are protected by siglock.
	 */
	if (task_is_stopped(task) &&
	    task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING))
		signal_wake_up_state(task, __TASK_STOPPED);

	spin_unlock(&task->sighand->siglock);

	retval = 0;
unlock_tasklist:
	write_unlock_irq(&tasklist_lock);
unlock_creds:
	mutex_unlock(&task->signal->cred_guard_mutex);
out:
	if (!retval) {
		wait_on_bit(&task->jobctl, JOBCTL_TRAPPING_BIT,
			    ptrace_trapping_sleep_fn, TASK_UNINTERRUPTIBLE);
		proc_ptrace_connector(task, PTRACE_ATTACH);
	}

	return retval;
}

/**
 * ptrace_traceme  --  helper for PTRACE_TRACEME
 *
 * Performs checks and sets PT_PTRACED.
 * Should be used by all ptrace implementations for PTRACE_TRACEME.
 */
static int ptrace_traceme(void)
{
	int ret = -EPERM;

	write_lock_irq(&tasklist_lock);
	/* Are we already being traced? */
	if (!current->ptrace) {
		ret = security_ptrace_traceme(current->parent);
		/*
		 * Check PF_EXITING to ensure ->real_parent has not passed
		 * exit_ptrace(). Otherwise we don't report the error but
		 * pretend ->real_parent untraces us right after return.
		 */
		if (!ret && !(current->real_parent->flags & PF_EXITING)) {
			current->ptrace = PT_PTRACED;
			__ptrace_link(current, current->real_parent);
		}
	}
	write_unlock_irq(&tasklist_lock);

	return ret;
}

/*
 * Called with irqs disabled, returns true if childs should reap themselves.
 */
static int ignoring_children(struct sighand_struct *sigh)
{
	int ret;
	spin_lock(&sigh->siglock);
	ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) ||
	      (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT);
	spin_unlock(&sigh->siglock);
	return ret;
}

/*
 * Called with tasklist_lock held for writing.
 * Unlink a traced task, and clean it up if it was a traced zombie.
 * Return true if it needs to be reaped with release_task().
 * (We can't call release_task() here because we already hold tasklist_lock.)
 *
 * If it's a zombie, our attachedness prevented normal parent notification
 * or self-reaping.  Do notification now if it would have happened earlier.
 * If it should reap itself, return true.
 *
 * If it's our own child, there is no notification to do. But if our normal
 * children self-reap, then this child was prevented by ptrace and we must
 * reap it now, in that case we must also wake up sub-threads sleeping in
 * do_wait().
 */
static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
{
	bool dead;

	__ptrace_unlink(p);

	if (p->exit_state != EXIT_ZOMBIE)
		return false;

	dead = !thread_group_leader(p);

	if (!dead && thread_group_empty(p)) {
		if (!same_thread_group(p->real_parent, tracer))
			dead = do_notify_parent(p, p->exit_signal);
		else if (ignoring_children(tracer->sighand)) {
			__wake_up_parent(p, tracer);
			dead = true;
		}
	}
	/* Mark it as in the process of being reaped. */
	if (dead)
		p->exit_state = EXIT_DEAD;
	return dead;
}

static int ptrace_detach(struct task_struct *child, unsigned int data)
{
	bool dead = false;

	if (!valid_signal(data))
		return -EIO;

	/* Architecture-specific hardware disable .. */
	ptrace_disable(child);
	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);

	write_lock_irq(&tasklist_lock);
	/*
	 * This child can be already killed. Make sure de_thread() or
	 * our sub-thread doing do_wait() didn't do release_task() yet.
	 */
	if (child->ptrace) {
		child->exit_code = data;
		dead = __ptrace_detach(current, child);
	}
	write_unlock_irq(&tasklist_lock);

	proc_ptrace_connector(child, PTRACE_DETACH);
	if (unlikely(dead))
		release_task(child);

	return 0;
}

/*
 * Detach all tasks we were using ptrace on. Called with tasklist held
 * for writing, and returns with it held too. But note it can release
 * and reacquire the lock.
 */
void exit_ptrace(struct task_struct *tracer)
	__releases(&tasklist_lock)
	__acquires(&tasklist_lock)
{
	struct task_struct *p, *n;
	LIST_HEAD(ptrace_dead);

	if (likely(list_empty(&tracer->ptraced)))
		return;

	list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) {
		if (unlikely(p->ptrace & PT_EXITKILL))
			send_sig_info(SIGKILL, SEND_SIG_FORCED, p);

		if (__ptrace_detach(tracer, p))
			list_add(&p->ptrace_entry, &ptrace_dead);
	}

	write_unlock_irq(&tasklist_lock);
	BUG_ON(!list_empty(&tracer->ptraced));

	list_for_each_entry_safe(p, n, &ptrace_dead, ptrace_entry) {
		list_del_init(&p->ptrace_entry);
		release_task(p);
	}

	write_lock_irq(&tasklist_lock);
}

int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
{
	int copied = 0;

	while (len > 0) {
		char buf[128];
		int this_len, retval;

		this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
		retval = access_process_vm(tsk, src, buf, this_len, 0);
		if (!retval) {
			if (copied)
				break;
			return -EIO;
		}
		if (copy_to_user(dst, buf, retval))
			return -EFAULT;
		copied += retval;
		src += retval;
		dst += retval;
		len -= retval;
	}
	return copied;
}

int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len)
{
	int copied = 0;

	while (len > 0) {
		char buf[128];
		int this_len, retval;

		this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
		if (copy_from_user(buf, src, this_len))
			return -EFAULT;
		retval = access_process_vm(tsk, dst, buf, this_len, 1);
		if (!retval) {
			if (copied)
				break;
			return -EIO;
		}
		copied += retval;
		src += retval;
		dst += retval;
		len -= retval;
	}
	return copied;
}

static int ptrace_setoptions(struct task_struct *child, unsigned long data)
{
	unsigned flags;

	if (data & ~(unsigned long)PTRACE_O_MASK)
		return -EINVAL;

	/* Avoid intermediate state when all opts are cleared */
	flags = child->ptrace;
	flags &= ~(PTRACE_O_MASK << PT_OPT_FLAG_SHIFT);
	flags |= (data << PT_OPT_FLAG_SHIFT);
	child->ptrace = flags;

	return 0;
}

static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info)
{
	unsigned long flags;
	int error = -ESRCH;

	if (lock_task_sighand(child, &flags)) {
		error = -EINVAL;
		if (likely(child->last_siginfo != NULL)) {
			*info = *child->last_siginfo;
			error = 0;
		}
		unlock_task_sighand(child, &flags);
	}
	return error;
}

static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info)
{
	unsigned long flags;
	int error = -ESRCH;

	if (lock_task_sighand(child, &flags)) {
		error = -EINVAL;
		if (likely(child->last_siginfo != NULL)) {
			*child->last_siginfo = *info;
			error = 0;
		}
		unlock_task_sighand(child, &flags);
	}
	return error;
}

static int ptrace_peek_siginfo(struct task_struct *child,
				unsigned long addr,
				unsigned long data)
{
	struct ptrace_peeksiginfo_args arg;
	struct sigpending *pending;
	struct sigqueue *q;
	int ret, i;

	ret = copy_from_user(&arg, (void __user *) addr,
				sizeof(struct ptrace_peeksiginfo_args));
	if (ret)
		return -EFAULT;

	if (arg.flags & ~PTRACE_PEEKSIGINFO_SHARED)
		return -EINVAL; /* unknown flags */

	if (arg.nr < 0)
		return -EINVAL;

	if (arg.flags & PTRACE_PEEKSIGINFO_SHARED)
		pending = &child->signal->shared_pending;
	else
		pending = &child->pending;

	for (i = 0; i < arg.nr; ) {
		siginfo_t info;
		s32 off = arg.off + i;

		spin_lock_irq(&child->sighand->siglock);
		list_for_each_entry(q, &pending->list, list) {
			if (!off--) {
				copy_siginfo(&info, &q->info);
				break;
			}
		}
		spin_unlock_irq(&child->sighand->siglock);

		if (off >= 0) /* beyond the end of the list */
			break;

#ifdef CONFIG_COMPAT
		if (unlikely(is_compat_task())) {
			compat_siginfo_t __user *uinfo = compat_ptr(data);

			ret = copy_siginfo_to_user32(uinfo, &info);
			ret |= __put_user(info.si_code, &uinfo->si_code);
		} else
#endif
		{
			siginfo_t __user *uinfo = (siginfo_t __user *) data;

			ret = copy_siginfo_to_user(uinfo, &info);
			ret |= __put_user(info.si_code, &uinfo->si_code);
		}

		if (ret) {
			ret = -EFAULT;
			break;
		}

		data += sizeof(siginfo_t);
		i++;

		if (signal_pending(current))
			break;

		cond_resched();
	}

	if (i > 0)
		return i;

	return ret;
}

#ifdef PTRACE_SINGLESTEP
#define is_singlestep(request)		((request) == PTRACE_SINGLESTEP)
#else
#define is_singlestep(request)		0
#endif

#ifdef PTRACE_SINGLEBLOCK
#define is_singleblock(request)		((request) == PTRACE_SINGLEBLOCK)
#else
#define is_singleblock(request)		0
#endif

#ifdef PTRACE_SYSEMU
#define is_sysemu_singlestep(request)	((request) == PTRACE_SYSEMU_SINGLESTEP)
#else
#define is_sysemu_singlestep(request)	0
#endif

static int ptrace_resume(struct task_struct *child, long request,
			 unsigned long data)
{
	if (!valid_signal(data))
		return -EIO;

	if (request == PTRACE_SYSCALL)
		set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
	else
		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);

#ifdef TIF_SYSCALL_EMU
	if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP)
		set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
	else
		clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
#endif

	if (is_singleblock(request)) {
		if (unlikely(!arch_has_block_step()))
			return -EIO;
		user_enable_block_step(child);
	} else if (is_singlestep(request) || is_sysemu_singlestep(request)) {
		if (unlikely(!arch_has_single_step()))
			return -EIO;
		user_enable_single_step(child);
	} else {
		user_disable_single_step(child);
	}

	child->exit_code = data;
	wake_up_state(child, __TASK_TRACED);

	return 0;
}

#ifdef CONFIG_HAVE_ARCH_TRACEHOOK

static const struct user_regset *
find_regset(const struct user_regset_view *view, unsigned int type)
{
	const struct user_regset *regset;
	int n;

	for (n = 0; n < view->n; ++n) {
		regset = view->regsets + n;
		if (regset->core_note_type == type)
			return regset;
	}

	return NULL;
}

static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
			 struct iovec *kiov)
{
	const struct user_regset_view *view = task_user_regset_view(task);
	const struct user_regset *regset = find_regset(view, type);
	int regset_no;

	if (!regset || (kiov->iov_len % regset->size) != 0)
		return -EINVAL;

	regset_no = regset - view->regsets;
	kiov->iov_len = min(kiov->iov_len,
			    (__kernel_size_t) (regset->n * regset->size));

	if (req == PTRACE_GETREGSET)
		return copy_regset_to_user(task, view, regset_no, 0,
					   kiov->iov_len, kiov->iov_base);
	else
		return copy_regset_from_user(task, view, regset_no, 0,
					     kiov->iov_len, kiov->iov_base);
}

/*
 * This is declared in linux/regset.h and defined in machine-dependent
 * code.  We put the export here, near the primary machine-neutral use,
 * to ensure no machine forgets it.
 */
EXPORT_SYMBOL_GPL(task_user_regset_view);
#endif

int ptrace_request(struct task_struct *child, long request,
		   unsigned long addr, unsigned long data)
{
	bool seized = child->ptrace & PT_SEIZED;
	int ret = -EIO;
	siginfo_t siginfo, *si;
	void __user *datavp = (void __user *) data;
	unsigned long __user *datalp = datavp;
	unsigned long flags;

	switch (request) {
	case PTRACE_PEEKTEXT:
	case PTRACE_PEEKDATA:
		return generic_ptrace_peekdata(child, addr, data);
	case PTRACE_POKETEXT:
	case PTRACE_POKEDATA:
		return generic_ptrace_pokedata(child, addr, data);

#ifdef PTRACE_OLDSETOPTIONS
	case PTRACE_OLDSETOPTIONS:
#endif
	case PTRACE_SETOPTIONS:
		ret = ptrace_setoptions(child, data);
		break;
	case PTRACE_GETEVENTMSG:
		ret = put_user(child->ptrace_message, datalp);
		break;

	case PTRACE_PEEKSIGINFO:
		ret = ptrace_peek_siginfo(child, addr, data);
		break;

	case PTRACE_GETSIGINFO:
		ret = ptrace_getsiginfo(child, &siginfo);
		if (!ret)
			ret = copy_siginfo_to_user(datavp, &siginfo);
		break;

	case PTRACE_SETSIGINFO:
		if (copy_from_user(&siginfo, datavp, sizeof siginfo))
			ret = -EFAULT;
		else
			ret = ptrace_setsiginfo(child, &siginfo);