コード例 #1
0
ファイル: linux.c プロジェクト: marcelhuberfoo/mpss-modules
static int
mic_fasync(int fd, struct file *filp, int on)
{
	int rc=0;

	if ((rc = fasync_helper(fd, filp, on, &mic_data.dd_fasync)) < 0) {
		return rc;
	}

	if (on) {
#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 18, 0))
		rc = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
#else
		__f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
#endif
		filp->private_data = filp;
	} else {
		filp->private_data = NULL;
	}

	return rc;
}
コード例 #2
0
ファイル: pid.c プロジェクト: Oleg-k/Cranium_Kernel
int is_container_init(struct task_struct *tsk)
{
	int ret = 0;
	struct pid *pid;

	rcu_read_lock();
	pid = task_pid(tsk);
	if (pid != NULL && pid->numbers[pid->level].nr == 1)
		ret = 1;
	rcu_read_unlock();

	return ret;
}
コード例 #3
0
static int __init kernel_init(void * unused)
{
	lock_kernel();
	/*
	 * init can run on any cpu.
	 */
	set_cpus_allowed_ptr(current, cpu_all_mask);
	/*
	 * Tell the world that we're going to be the grim
	 * reaper of innocent orphaned children.
	 *
	 * We don't want people to have to make incorrect
	 * assumptions about where in the task array this
	 * can be found.
	 */
	init_pid_ns.child_reaper = current;

	cad_pid = task_pid(current);

	smp_prepare_cpus(setup_max_cpus);

	do_pre_smp_initcalls();
	start_boot_trace();

	smp_init();
	sched_init_smp();

	do_basic_setup();

	/*
	 * check if there is an early userspace init.  If yes, let it do all
	 * the work
	 */

	if (!ramdisk_execute_command)
		ramdisk_execute_command = "/init";

	if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
		ramdisk_execute_command = NULL;
		prepare_namespace();
	}

	/*
	 * Ok, we have completed the initial bootup, and
	 * we're essentially up and running. Get rid of the
	 * initmem segments and start the user-mode stuff..
	 */

	init_post();
	return 0;
}
コード例 #4
0
/*
 * We fill out the fields in the waiter to store the information about
 * the deadlock. We print when we return. act_waiter can be NULL in
 * case of a remove waiter operation.
 */
void debug_rt_mutex_deadlock(int detect, struct rt_mutex_waiter *act_waiter,
			     struct rt_mutex *lock)
{
	struct task_struct *task;

	if (!debug_locks || detect || !act_waiter)
		return;

	task = rt_mutex_owner(act_waiter->lock);
	if (task && task != current) {
		act_waiter->deadlock_task_pid = get_pid(task_pid(task));
		act_waiter->deadlock_lock = lock;
	}
}
コード例 #5
0
ファイル: kperf.c プロジェクト: wzw19890321/xnu-1
void
kperf_on_cpu_internal(thread_t thread, thread_continue_t continuation,
                      uintptr_t *starting_fp)
{
	if (kperf_kdebug_cswitch) {
		/* trace the new thread's PID for Instruments */
		int pid = task_pid(get_threadtask(thread));

		BUF_DATA(PERF_TI_CSWITCH, thread_tid(thread), pid);
	}
	if (kperf_lightweight_pet_active) {
		kperf_pet_on_cpu(thread, continuation, starting_fp);
	}
}
コード例 #6
0
ファイル: rtmutex-debug.c プロジェクト: mkrufky/linux
/*
 * We fill out the fields in the waiter to store the information about
 * the deadlock. We print when we return. act_waiter can be NULL in
 * case of a remove waiter operation.
 */
void debug_rt_mutex_deadlock(enum rtmutex_chainwalk chwalk,
			     struct rt_mutex_waiter *act_waiter,
			     struct rt_mutex *lock)
{
	struct task_struct *task;

	if (!debug_locks || chwalk == RT_MUTEX_FULL_CHAINWALK || !act_waiter)
		return;

	task = rt_mutex_owner(act_waiter->lock);
	if (task && task != current) {
		act_waiter->deadlock_task_pid = get_pid(task_pid(task));
		act_waiter->deadlock_lock = lock;
	}
}
コード例 #7
0
ファイル: backfire.c プロジェクト: 1023xp/training
static ssize_t
backfire_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
{
	int signo;
	struct pid *pid;

	if (sscanf(buf, "%d", &signo) >= 1) {
		if (signo > 0 && signo < 32) {
			pid = get_pid(task_pid(current));
			do_gettimeofday(&sendtime);
			kill_pid(pid, signo, 1);
		} else
			printk(KERN_ERR "Invalid signal no. %d\n", signo);
	}
	return strlen(buf);
}
コード例 #8
0
static struct pid *good_sigevent(sigevent_t * event)
{
	struct task_struct *rtn = current->group_leader;

	if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
		(!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
		 !same_thread_group(rtn, current) ||
		 (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
		return NULL;

	if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
	    ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
		return NULL;

	return task_pid(rtn);
}
コード例 #9
0
ファイル: kperf_timer.c プロジェクト: wzw19890321/xnu-1
void
kperf_ipi_handler(void *param)
{
	struct kperf_context ctx;
	struct kperf_timer *timer = param;

	assert(timer != NULL);

	/* Always cut a tracepoint to show a sample event occurred */
	BUF_DATA(PERF_TM_HNDLR | DBG_FUNC_START, 0);

	int ncpu = cpu_number();

	struct kperf_sample *intbuf = kperf_intr_sample_buffer();

	/* On a timer, we can see the "real" current thread */
	ctx.cur_thread = current_thread();
	ctx.cur_pid = task_pid(get_threadtask(ctx.cur_thread));

	/* who fired */
	ctx.trigger_type = TRIGGER_TYPE_TIMER;
	ctx.trigger_id = (unsigned int)(timer - kperf_timerv);

	if (ctx.trigger_id == pet_timer_id && ncpu < machine_info.logical_cpu_max) {
		kperf_thread_on_cpus[ncpu] = ctx.cur_thread;
	}

	/* make sure sampling is on */
	unsigned int status = kperf_sampling_status();
	if (status == KPERF_SAMPLING_OFF) {
		BUF_INFO(PERF_TM_HNDLR | DBG_FUNC_END, SAMPLE_OFF);
		return;
	} else if (status == KPERF_SAMPLING_SHUTDOWN) {
		BUF_INFO(PERF_TM_HNDLR | DBG_FUNC_END, SAMPLE_SHUTDOWN);
		return;
	}

	/* call the action -- kernel-only from interrupt, pend user */
	int r = kperf_sample(intbuf, &ctx, timer->actionid, SAMPLE_FLAG_PEND_USER);

	/* end tracepoint is informational */
	BUF_INFO(PERF_TM_HNDLR | DBG_FUNC_END, r);

#if defined(__x86_64__)
	(void)atomic_bit_clear(&(timer->pending_cpus), ncpu, __ATOMIC_RELAXED);
#endif /* defined(__x86_64__) */
}
コード例 #10
0
ファイル: n_r3964.c プロジェクト: PennPanda/linux-repo
static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
			  unsigned char __user * buf, size_t nr)
{
	struct r3964_info *pInfo = (struct r3964_info *)tty->disc_data;
	struct r3964_client_info *pClient;
	struct r3964_message *pMsg;
	struct r3964_client_message theMsg;
	int count;

	TRACE_L("read()");

	pClient = findClient(pInfo, task_pid(current));
	if (pClient) {
		pMsg = remove_msg(pInfo, pClient);
		if (pMsg == NULL) {
			/* no messages available. */
			if (file->f_flags & O_NONBLOCK) {
				return -EAGAIN;
			}
			/* block until there is a message: */
			wait_event_interruptible(pInfo->read_wait,
					(pMsg = remove_msg(pInfo, pClient)));
		}

		/* If we still haven't got a message, we must have been signalled */

		if (!pMsg)
			return -EINTR;

		/* deliver msg to client process: */
		theMsg.msg_id = pMsg->msg_id;
		theMsg.arg = pMsg->arg;
		theMsg.error_code = pMsg->error_code;
		count = sizeof(struct r3964_client_message);

		kfree(pMsg);
		TRACE_M("r3964_read - msg kfree %p", pMsg);

		if (copy_to_user(buf, &theMsg, count))
			return -EFAULT;

		TRACE_PS("read - return %d", count);
		return count;
	}
	return -EPERM;
}
コード例 #11
0
static int
mic_fasync(int fd, struct file *filp, int on)
{
	int rc;

	if ((rc = fasync_helper(fd, filp, on, &mic_data.dd_fasync)) < 0) {
		return rc;
	}

	if (on) {
		rc = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
		filp->private_data = filp;
	} else {
		filp->private_data = NULL;
	}

	return rc;
}
コード例 #12
0
ファイル: posix-timers.c プロジェクト: garyvan/openwrt-1.6
static struct pid *good_sigevent(sigevent_t * event)
{
	struct task_struct *rtn = current->group_leader;
	int sig = event->sigev_signo;

	if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
		(!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
		 !same_thread_group(rtn, current) ||
		 (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
		return NULL;

	if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
	    (sig <= 0 || sig > SIGRTMAX || sig_kernel_only(sig) ||
	     sig_kernel_coredump(sig)))
		return NULL;

	return task_pid(rtn);
}
コード例 #13
0
ファイル: uloop.c プロジェクト: wosigh/patches
static int ulo_ctl_queue(struct ulo_dev *dev, int qindex,
			 union ulo_ctl __user *uarg)
{
	struct ulo_qelem *qelem;

	/* this element will be freed by ulo_xfer_{start,end}() */
	qelem = kmem_cache_alloc(ulo_cache, GFP_KERNEL);
	if (IS_ERR(qelem))
		return PTR_ERR(qelem);
	if (unlikely(copy_from_user(&qelem->ctl, uarg, sizeof(*uarg)))) {
		kmem_cache_free(ulo_cache, qelem);
		return -EFAULT;
	}
	if (qindex == UloQ_READY)
		qelem->ctl.ready.pid = task_pid(current);

	ulo_append(dev, qindex, qelem);
	return 0;
}
コード例 #14
0
ファイル: kthread.c プロジェクト: michaelknoch/systemsoftware
static void __exit ModExit(void)
{
	if(thread_id){
		kill_pid(task_pid(thread_id), SIGTERM, 1);
	}
	
	wait_for_completion(&on_exit);

	device_destroy(template_class, device_number);
	class_destroy(template_class);

	printk("trying to unregister 0x%x\n", device_number);
	
	cdev_del( driver_object );
	unregister_chrdev_region( device_number, 1 );
	
	printk("exiting\n");
	
}
コード例 #15
0
ファイル: mac_mach.c プロジェクト: wzw19890321/xnu-1
static struct proc *
mac_task_get_proc(struct task *task)
{
	if (task == current_task())
		return proc_self();

	/*
	 * Tasks don't really hold a reference on a proc unless the
	 * calling thread belongs to the task in question.
	 */
	int pid = task_pid(task);
	struct proc *p = proc_find(pid);

	if (p != NULL) {
		if (proc_task(p) == task)
			return p;
		proc_rele(p);
	}
	return NULL;
}
コード例 #16
0
ファイル: kperf.c プロジェクト: wzw19890321/xnu-1
int
kperf_port_to_pid(mach_port_name_t portname)
{
	task_t task;
	int pid;

	if (!MACH_PORT_VALID(portname)) {
		return -1;
	}

	task = port_name_to_task(portname);

	if (task == TASK_NULL) {
		return -1;
	}

	pid = task_pid(task);

	task_deallocate_internal(task);

	return pid;
}
コード例 #17
0
ファイル: s3c_g3d.c プロジェクト: moikop/Astrum-Kernel
void register_alloc_info(int index,u64 uiAllocedMemMap )
{
	unsigned int id = g3d_bootm[index].file_desc_id;
	alloc_info *s_info = alloc_info_head;

//	printk("<register_alloc_info index=%d id=0x%x AllocedMemMap=0x%x>\n",index,id,uiAllocedMemMap);
	while(s_info!=NULL)
	{
		if(s_info->file_desc_id == id) break;
		s_info = s_info->next;
	}
	
	if(s_info)
	{
		if(s_info->uiAllocedMemMap & uiAllocedMemMap) 
				printk("err uiAllocedMemMap\n");
		else s_info->uiAllocedMemMap|=uiAllocedMemMap;
	}
	else
	{
		s_info = vmalloc(sizeof(alloc_info));	
		s_info->file_desc_id 	= id;
		s_info->pId				= task_pid(current);
		
		s_info->next 			= NULL;
		s_info->uiAllocedMemMap	= uiAllocedMemMap;

		if(alloc_info_tail)	
			alloc_info_tail->next = s_info;
		else	
			alloc_info_head = s_info;
		alloc_info_tail = s_info;

	}
#ifdef DEBUG_S3C_G3D
	g3d_alloc_info_dump();
#endif

}
コード例 #18
0
ファイル: n_r3964.c プロジェクト: ManiacTwister/linux-hnd
/* Called without the kernel lock held - fine */
static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
			struct poll_table_struct *wait)
{
	struct r3964_info *pInfo = (struct r3964_info *)tty->disc_data;
	struct r3964_client_info *pClient;
	struct r3964_message *pMsg = NULL;
	unsigned long flags;
	int result = POLLOUT;

	TRACE_L("POLL");

	pClient = findClient(pInfo, task_pid(current));
	if (pClient) {
		poll_wait(file, &pInfo->read_wait, wait);
		spin_lock_irqsave(&pInfo->lock, flags);
		pMsg = pClient->first_msg;
		spin_unlock_irqrestore(&pInfo->lock, flags);
		if (pMsg)
			result |= POLLIN | POLLRDNORM;
	} else {
		result = -EINVAL;
	}
	return result;
}
コード例 #19
0
ファイル: n_r3964.c プロジェクト: ManiacTwister/linux-hnd
static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
			   const unsigned char *data, size_t count)
{
	struct r3964_info *pInfo = (struct r3964_info *)tty->disc_data;
	struct r3964_block_header *pHeader;
	struct r3964_client_info *pClient;
	unsigned char *new_data;

	TRACE_L("write request, %d characters", count);
/* 
 * Verify the pointers 
 */

	if (!pInfo)
		return -EIO;

/*
 * Ensure that the caller does not wish to send too much.
 */
	if (count > R3964_MTU) {
		if (pInfo->flags & R3964_DEBUG) {
			TRACE_L(KERN_WARNING "r3964_write: truncating user "
				"packet from %u to mtu %d", count, R3964_MTU);
		}
		count = R3964_MTU;
	}
/*
 * Allocate a buffer for the data and copy it from the buffer with header prepended
 */
	new_data = kmalloc(count + sizeof(struct r3964_block_header),
			GFP_KERNEL);
	TRACE_M("r3964_write - kmalloc %p", new_data);
	if (new_data == NULL) {
		if (pInfo->flags & R3964_DEBUG) {
			printk(KERN_ERR "r3964_write: no memory\n");
		}
		return -ENOSPC;
	}

	pHeader = (struct r3964_block_header *)new_data;
	pHeader->data = new_data + sizeof(struct r3964_block_header);
	pHeader->length = count;
	pHeader->locks = 0;
	pHeader->owner = NULL;

	pClient = findClient(pInfo, task_pid(current));
	if (pClient) {
		pHeader->owner = pClient;
	}

	memcpy(pHeader->data, data, count);	/* We already verified this */

	if (pInfo->flags & R3964_DEBUG) {
		dump_block(pHeader->data, count);
	}

/*
 * Add buffer to transmit-queue:
 */
	add_tx_queue(pInfo, pHeader);
	trigger_transmit(pInfo);

	return 0;
}
コード例 #20
0
ファイル: sys.c プロジェクト: maraz/linux-2.6
/*
 * This needs some heavy checking ...
 * I just haven't the stomach for it. I also don't fully
 * understand sessions/pgrp etc. Let somebody who does explain it.
 *
 * OK, I think I have the protection semantics right.... this is really
 * only important on a multi-user system anyway, to make sure one user
 * can't send a signal to a process owned by another.  -TYT, 12/12/91
 *
 * Auch. Had to add the 'did_exec' flag to conform completely to POSIX.
 * LBT 04.03.94
 */
asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
{
	struct task_struct *p;
	struct task_struct *group_leader = current->group_leader;
	struct pid *pgrp;
	int err;

	if (!pid)
		pid = task_pid_vnr(group_leader);
	if (!pgid)
		pgid = pid;
	if (pgid < 0)
		return -EINVAL;

	/* From this point forward we keep holding onto the tasklist lock
	 * so that our parent does not change from under us. -DaveM
	 */
	write_lock_irq(&tasklist_lock);

	err = -ESRCH;
	p = find_task_by_vpid(pid);
	if (!p)
		goto out;

	err = -EINVAL;
	if (!thread_group_leader(p))
		goto out;

	if (same_thread_group(p->real_parent, group_leader)) {
		err = -EPERM;
		if (task_session(p) != task_session(group_leader))
			goto out;
		err = -EACCES;
		if (p->did_exec)
			goto out;
	} else {
		err = -ESRCH;
		if (p != group_leader)
			goto out;
	}

	err = -EPERM;
	if (p->signal->leader)
		goto out;

	pgrp = task_pid(p);
	if (pgid != pid) {
		struct task_struct *g;

		pgrp = find_vpid(pgid);
		g = pid_task(pgrp, PIDTYPE_PGID);
		if (!g || task_session(g) != task_session(group_leader))
			goto out;
	}

	err = security_task_setpgid(p, pgid);
	if (err)
		goto out;

	if (task_pgrp(p) != pgrp) {
		change_pid(p, PIDTYPE_PGID, pgrp);
		set_task_pgrp(p, pid_nr(pgrp));
	}

	err = 0;
out:
	/* All paths lead to here, thus we are safe. -DaveM */
	write_unlock_irq(&tasklist_lock);
	return err;
}
コード例 #21
0
ファイル: main.c プロジェクト: millken/zhuxianB30
static int __init kernel_init(void * unused)
{
	lock_kernel();

	/*
	 * init can allocate pages on any node
	 */
	set_mems_allowed(node_possible_map);

#ifdef 	CONFIG_SYS_HAS_CONTROL_CPU
	/*
	 * init can run on cpu0 only .
	 */
	set_cpus_allowed_ptr(current, cpumask_of(0));
#else
	/*
	 * init can run on any cpu .
	 */
	set_cpus_allowed_ptr(current, cpu_all_mask);
#endif
	/*
	 * Tell the world that we're going to be the grim
	 * reaper of innocent orphaned children.
	 *
	 * We don't want people to have to make incorrect
	 * assumptions about where in the task array this
	 * can be found.
	 */
	init_pid_ns.child_reaper = current;

	cad_pid = task_pid(current);

	smp_prepare_cpus(setup_max_cpus);

	do_pre_smp_initcalls();
	start_boot_trace();

	smp_init();
	sched_init_smp();

#ifdef 	CONFIG_SYS_HAS_CONTROL_CPU
	/* HeJianjun modified for bug 148, 
	 * we run linux local processes on only cpu0, other cpu's are just for running dapp */
	set_cpus_allowed_ptr(current, cpumask_of(0));
#endif

	do_basic_setup();

	/*
	 * check if there is an early userspace init.  If yes, let it do all
	 * the work
	 */

	if (!ramdisk_execute_command)
		ramdisk_execute_command = "/init";

	if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
		ramdisk_execute_command = NULL;
		prepare_namespace();
	}

	/*
	 * Ok, we have completed the initial bootup, and
	 * we're essentially up and running. Get rid of the
	 * initmem segments and start the user-mode stuff..
	 */

	init_post();
	return 0;
}
コード例 #22
0
/**
 * ecryptfs_miscdev_write - handle write to daemon miscdev handle
 * @file: File for misc dev handle (ignored)
 * @buf: Buffer containing user data
 * @count: Amount of data in @buf
 * @ppos: Pointer to offset in file (ignored)
 *
 * miscdevfs packet format:
 *  Octet 0: Type
 *  Octets 1-4: network byte order msg_ctx->counter (0's for non-response)
 *  Octets 5-N0: Size of struct ecryptfs_message to follow
 *  Octets N0-N1: struct ecryptfs_message (including data)
 *
 * Returns the number of bytes read from @buf
 */
static ssize_t
ecryptfs_miscdev_write(struct file *file, const char __user *buf,
		       size_t count, loff_t *ppos)
{
	__be32 counter_nbo;
	u32 seq;
	size_t packet_size, packet_size_length, i;
	ssize_t sz = 0;
	char *data;
	uid_t euid = current_euid();
	unsigned char packet_size_peek[3];
	int rc;

	if (count == 0) {
		goto out;
	} else if (count == (1 + 4)) {
		/* Likely a harmless MSG_HELO or MSG_QUIT - no packet length */
		goto memdup;
	} else if (count < (1 + 4 + 1)
		   || count > (1 + 4 + 2 + sizeof(struct ecryptfs_message) + 4
			       + ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES)) {
		printk(KERN_WARNING "%s: Acceptable packet size range is "
		       "[%d-%lu], but amount of data written is [%zu].",
		       __func__, (1 + 4 + 1),
		       (1 + 4 + 2 + sizeof(struct ecryptfs_message) + 4
			+ ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES), count);
		return -EINVAL;
	}

	if (copy_from_user(packet_size_peek, (buf + 1 + 4),
			   sizeof(packet_size_peek))) {
		printk(KERN_WARNING "%s: Error while inspecting packet size\n",
		       __func__);
		return -EFAULT;
	}

	rc = ecryptfs_parse_packet_length(packet_size_peek, &packet_size,
					  &packet_size_length);
	if (rc) {
		printk(KERN_WARNING "%s: Error parsing packet length; "
		       "rc = [%d]\n", __func__, rc);
		return rc;
	}

	if ((1 + 4 + packet_size_length + packet_size) != count) {
		printk(KERN_WARNING "%s: Invalid packet size [%zu]\n", __func__,
		       packet_size);
		return -EINVAL;
	}

memdup:
	data = memdup_user(buf, count);
	if (IS_ERR(data)) {
		printk(KERN_ERR "%s: memdup_user returned error [%ld]\n",
		       __func__, PTR_ERR(data));
		goto out;
	}
	sz = count;
	i = 0;
	switch (data[i++]) {
	case ECRYPTFS_MSG_RESPONSE:
		if (count < (1 + 4 + 1 + sizeof(struct ecryptfs_message))) {
			printk(KERN_WARNING "%s: Minimum acceptable packet "
			       "size is [%zd], but amount of data written is "
			       "only [%zd]. Discarding response packet.\n",
			       __func__,
			       (1 + 4 + 1 + sizeof(struct ecryptfs_message)),
			       count);
			goto out_free;
		}
		memcpy(&counter_nbo, &data[i], 4);
		seq = be32_to_cpu(counter_nbo);
		i += 4 + packet_size_length;
		rc = ecryptfs_miscdev_response(&data[i], packet_size,
					       euid, current_user_ns(),
					       task_pid(current), seq);
		if (rc)
			printk(KERN_WARNING "%s: Failed to deliver miscdev "
			       "response to requesting operation; rc = [%d]\n",
			       __func__, rc);
		break;
	case ECRYPTFS_MSG_HELO:
	case ECRYPTFS_MSG_QUIT:
		break;
	default:
		ecryptfs_printk(KERN_WARNING, "Dropping miscdev "
				"message of unrecognized type [%d]\n",
				data[0]);
		break;
	}
out_free:
	kfree(data);
out:
	return sz;
}
コード例 #23
0
/**
 * ecryptfs_miscdev_read - format and send message from queue
 * @file: fs/ecryptfs/euid miscdevfs handle (ignored)
 * @buf: User buffer into which to copy the next message on the daemon queue
 * @count: Amount of space available in @buf
 * @ppos: Offset in file (ignored)
 *
 * Pulls the most recent message from the daemon queue, formats it for
 * being sent via a miscdevfs handle, and copies it into @buf
 *
 * Returns the number of bytes copied into the user buffer
 */
static ssize_t
ecryptfs_miscdev_read(struct file *file, char __user *buf, size_t count,
		      loff_t *ppos)
{
	struct ecryptfs_daemon *daemon;
	struct ecryptfs_msg_ctx *msg_ctx;
	size_t packet_length_size;
	char packet_length[3];
	size_t i;
	size_t total_length;
	uid_t euid = current_euid();
	int rc;

	mutex_lock(&ecryptfs_daemon_hash_mux);
	/* TODO: Just use file->private_data? */
	rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns());
	if (rc || !daemon) {
		mutex_unlock(&ecryptfs_daemon_hash_mux);
		return -EINVAL;
	}
	mutex_lock(&daemon->mux);
	if (task_pid(current) != daemon->pid) {
		mutex_unlock(&daemon->mux);
		mutex_unlock(&ecryptfs_daemon_hash_mux);
		return -EPERM;
	}
	if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
		rc = 0;
		mutex_unlock(&ecryptfs_daemon_hash_mux);
		printk(KERN_WARNING "%s: Attempt to read from zombified "
		       "daemon\n", __func__);
		goto out_unlock_daemon;
	}
	if (daemon->flags & ECRYPTFS_DAEMON_IN_READ) {
		rc = 0;
		mutex_unlock(&ecryptfs_daemon_hash_mux);
		goto out_unlock_daemon;
	}
	/* This daemon will not go away so long as this flag is set */
	daemon->flags |= ECRYPTFS_DAEMON_IN_READ;
	mutex_unlock(&ecryptfs_daemon_hash_mux);
check_list:
	if (list_empty(&daemon->msg_ctx_out_queue)) {
		mutex_unlock(&daemon->mux);
		rc = wait_event_interruptible(
			daemon->wait, !list_empty(&daemon->msg_ctx_out_queue));
		mutex_lock(&daemon->mux);
		if (rc < 0) {
			rc = 0;
			goto out_unlock_daemon;
		}
	}
	if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
		rc = 0;
		goto out_unlock_daemon;
	}
	if (list_empty(&daemon->msg_ctx_out_queue)) {
		/* Something else jumped in since the
		 * wait_event_interruptable() and removed the
		 * message from the queue; try again */
		goto check_list;
	}
	msg_ctx = list_first_entry(&daemon->msg_ctx_out_queue,
				   struct ecryptfs_msg_ctx, daemon_out_list);
	BUG_ON(!msg_ctx);
	mutex_lock(&msg_ctx->mux);
	if (msg_ctx->msg) {
		rc = ecryptfs_write_packet_length(packet_length,
						  msg_ctx->msg_size,
						  &packet_length_size);
		if (rc) {
			rc = 0;
			printk(KERN_WARNING "%s: Error writing packet length; "
			       "rc = [%d]\n", __func__, rc);
			goto out_unlock_msg_ctx;
		}
	} else {
		packet_length_size = 0;
		msg_ctx->msg_size = 0;
	}
	/* miscdevfs packet format:
	 *  Octet 0: Type
	 *  Octets 1-4: network byte order msg_ctx->counter
	 *  Octets 5-N0: Size of struct ecryptfs_message to follow
	 *  Octets N0-N1: struct ecryptfs_message (including data)
	 *
	 *  Octets 5-N1 not written if the packet type does not
	 *  include a message */
	total_length = (1 + 4 + packet_length_size + msg_ctx->msg_size);
	if (count < total_length) {
		rc = 0;
		printk(KERN_WARNING "%s: Only given user buffer of "
		       "size [%zd], but we need [%zd] to read the "
		       "pending message\n", __func__, count, total_length);
		goto out_unlock_msg_ctx;
	}
	rc = -EFAULT;
	if (put_user(msg_ctx->type, buf))
		goto out_unlock_msg_ctx;
	if (put_user(cpu_to_be32(msg_ctx->counter), (__be32 __user *)(buf + 1)))
		goto out_unlock_msg_ctx;
	i = 5;
	if (msg_ctx->msg) {
		if (copy_to_user(&buf[i], packet_length, packet_length_size))
			goto out_unlock_msg_ctx;
		i += packet_length_size;
		if (copy_to_user(&buf[i], msg_ctx->msg, msg_ctx->msg_size))
			goto out_unlock_msg_ctx;
		i += msg_ctx->msg_size;
	}
	rc = i;
	list_del(&msg_ctx->daemon_out_list);
	kfree(msg_ctx->msg);
	msg_ctx->msg = NULL;
	/* We do not expect a reply from the userspace daemon for any
	 * message type other than ECRYPTFS_MSG_REQUEST */
	if (msg_ctx->type != ECRYPTFS_MSG_REQUEST)
		ecryptfs_msg_ctx_alloc_to_free(msg_ctx);
out_unlock_msg_ctx:
	mutex_unlock(&msg_ctx->mux);
out_unlock_daemon:
	daemon->flags &= ~ECRYPTFS_DAEMON_IN_READ;
	mutex_unlock(&daemon->mux);
	return rc;
}
コード例 #24
0
static int __init kernel_init(void * unused)
{
	lock_kernel();

	/*
	 * init can allocate pages on any node
	 */
	set_mems_allowed(node_possible_map);
	/*
	 * init can run on any cpu.
	 */
	set_cpus_allowed_ptr(current, cpu_all_mask);
	/*
	 * Tell the world that we're going to be the grim
	 * reaper of innocent orphaned children.
	 *
	 * We don't want people to have to make incorrect
	 * assumptions about where in the task array this
	 * can be found.
	 */
	init_pid_ns.child_reaper = current;

	cad_pid = task_pid(current);

	smp_prepare_cpus(setup_max_cpus);

	do_pre_smp_initcalls();
	start_boot_trace();

	smp_init();
	sched_init_smp();

	do_basic_setup();

	/*
	 * check if there is an early userspace init.  If yes, let it do all
	 * the work
	 */

	if (!ramdisk_execute_command)
		ramdisk_execute_command = "/init";

	if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
		ramdisk_execute_command = NULL;
		prepare_namespace();
	}
#ifdef CONFIG_PREEMPT_RT
	WARN_ON(irqs_disabled());
#endif

#define DEBUG_COUNT (defined(CONFIG_DEBUG_RT_MUTEXES) + defined(CONFIG_IRQSOFF_TRACER) + defined(CONFIG_PREEMPT_TRACER) + defined(CONFIG_STACK_TRACER) + defined(CONFIG_INTERRUPT_OFF_HIST) + defined(CONFIG_PREEMPT_OFF_HIST) + defined(CONFIG_WAKEUP_LATENCY_HIST) + defined(CONFIG_DEBUG_SLAB) + defined(CONFIG_DEBUG_PAGEALLOC) + defined(CONFIG_LOCKDEP) + (defined(CONFIG_FTRACE) - defined(CONFIG_FTRACE_MCOUNT_RECORD)))

#if DEBUG_COUNT > 0
	printk(KERN_ERR "*****************************************************************************\n");
	printk(KERN_ERR "*                                                                           *\n");
#if DEBUG_COUNT == 1
	printk(KERN_ERR "*  REMINDER, the following debugging option is turned on in your .config:   *\n");
#else
	printk(KERN_ERR "*  REMINDER, the following debugging options are turned on in your .config: *\n");
#endif
	printk(KERN_ERR "*                                                                           *\n");
#ifdef CONFIG_DEBUG_RT_MUTEXES
	printk(KERN_ERR "*        CONFIG_DEBUG_RT_MUTEXES                                            *\n");
#endif
#ifdef CONFIG_IRQSOFF_TRACER
	printk(KERN_ERR "*        CONFIG_IRQSOFF_TRACER                                              *\n");
#endif
#ifdef CONFIG_PREEMPT_TRACER
	printk(KERN_ERR "*        CONFIG_PREEMPT_TRACER                                              *\n");
#endif
#if defined(CONFIG_FTRACE) && !defined(CONFIG_FTRACE_MCOUNT_RECORD)
	printk(KERN_ERR "*        CONFIG_FTRACE                                                      *\n");
#endif
#ifdef CONFIG_INTERRUPT_OFF_HIST
	printk(KERN_ERR "*        CONFIG_INTERRUPT_OFF_HIST                                          *\n");
#endif
#ifdef CONFIG_PREEMPT_OFF_HIST
	printk(KERN_ERR "*        CONFIG_PREEMPT_OFF_HIST                                            *\n");
#endif
#ifdef CONFIG_WAKEUP_LATENCY_HIST
	printk(KERN_ERR "*        CONFIG_WAKEUP_LATENCY_HIST                                         *\n");
#endif
#ifdef CONFIG_DEBUG_SLAB
	printk(KERN_ERR "*        CONFIG_DEBUG_SLAB                                                  *\n");
#endif
#ifdef CONFIG_DEBUG_PAGEALLOC
	printk(KERN_ERR "*        CONFIG_DEBUG_PAGEALLOC                                             *\n");
#endif
#ifdef CONFIG_LOCKDEP
	printk(KERN_ERR "*        CONFIG_LOCKDEP                                                     *\n");
#endif
	printk(KERN_ERR "*                                                                           *\n");
#if DEBUG_COUNT == 1
	printk(KERN_ERR "*  it may increase runtime overhead and latencies.                          *\n");
#else
	printk(KERN_ERR "*  they may increase runtime overhead and latencies.                        *\n");
#endif
	printk(KERN_ERR "*                                                                           *\n");
	printk(KERN_ERR "*****************************************************************************\n");
#endif
	/*
	 * Ok, we have completed the initial bootup, and
	 * we're essentially up and running. Get rid of the
	 * initmem segments and start the user-mode stuff..
	 */

	init_post();
	return 0;
}
コード例 #25
0
ファイル: main.c プロジェクト: possiblybhavin/mx27_drv
static int init(void * unused)
{
	lock_kernel();
	/*
	 * init can run on any cpu.
	 */
	set_cpus_allowed(current, CPU_MASK_ALL);
	/*
	 * Tell the world that we're going to be the grim
	 * reaper of innocent orphaned children.
	 *
	 * We don't want people to have to make incorrect
	 * assumptions about where in the task array this
	 * can be found.
	 */
	child_reaper = current;

	cad_pid = task_pid(current);

	smp_prepare_cpus(max_cpus);

	do_pre_smp_initcalls();

	smp_init();
	sched_init_smp();

	cpuset_init_smp();

	/*
	 * Do this before initcalls, because some drivers want to access
	 * firmware files.
	 */
	populate_rootfs();

	do_basic_setup();

	/*
	 * check if there is an early userspace init.  If yes, let it do all
	 * the work
	 */

	if (!ramdisk_execute_command)
		ramdisk_execute_command = "/init";

	if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
		ramdisk_execute_command = NULL;
		prepare_namespace();
	}

	/*
	 * Ok, we have completed the initial bootup, and
	 * we're essentially up and running. Get rid of the
	 * initmem segments and start the user-mode stuff..
	 */
	free_initmem();
	unlock_kernel();
	mark_rodata_ro();
	system_state = SYSTEM_RUNNING;
	numa_default_policy();

	if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
		printk(KERN_WARNING "Warning: unable to open an initial console.\n");

	(void) sys_dup(0);
	(void) sys_dup(0);

	if (ramdisk_execute_command) {
		run_init_process(ramdisk_execute_command);
		printk(KERN_WARNING "Failed to execute %s\n",
				ramdisk_execute_command);
	}

	/*
	 * We try each of these until one succeeds.
	 *
	 * The Bourne shell can be used instead of init if we are 
	 * trying to recover a really broken machine.
	 */
	if (execute_command) {
		run_init_process(execute_command);
		printk(KERN_WARNING "Failed to execute %s.  Attempting "
					"defaults...\n", execute_command);
	}
	run_init_process("/sbin/init");
	run_init_process("/etc/init");
	run_init_process("/bin/init");
	run_init_process("/bin/sh");

	panic("No init found.  Try passing init= option to kernel.");
}
コード例 #26
0
ファイル: miscdev.c プロジェクト: maraz/linux-2.6
/**
 * ecryptfs_miscdev_write - handle write to daemon miscdev handle
 * @file: File for misc dev handle (ignored)
 * @buf: Buffer containing user data
 * @count: Amount of data in @buf
 * @ppos: Pointer to offset in file (ignored)
 *
 * miscdevfs packet format:
 *  Octet 0: Type
 *  Octets 1-4: network byte order msg_ctx->counter (0's for non-response)
 *  Octets 5-N0: Size of struct ecryptfs_message to follow
 *  Octets N0-N1: struct ecryptfs_message (including data)
 *
 * Returns the number of bytes read from @buf
 */
static ssize_t
ecryptfs_miscdev_write(struct file *file, const char __user *buf,
		       size_t count, loff_t *ppos)
{
	__be32 counter_nbo;
	u32 seq;
	size_t packet_size, packet_size_length, i;
	ssize_t sz = 0;
	char *data;
	int rc;

	if (count == 0)
		goto out;
	data = kmalloc(count, GFP_KERNEL);
	if (!data) {
		printk(KERN_ERR "%s: Out of memory whilst attempting to "
		       "kmalloc([%Zd], GFP_KERNEL)\n", __func__, count);
		goto out;
	}
	rc = copy_from_user(data, buf, count);
	if (rc) {
		printk(KERN_ERR "%s: copy_from_user returned error [%d]\n",
		       __func__, rc);
		goto out_free;
	}
	sz = count;
	i = 0;
	switch (data[i++]) {
	case ECRYPTFS_MSG_RESPONSE:
		if (count < (1 + 4 + 1 + sizeof(struct ecryptfs_message))) {
			printk(KERN_WARNING "%s: Minimum acceptable packet "
			       "size is [%Zd], but amount of data written is "
			       "only [%Zd]. Discarding response packet.\n",
			       __func__,
			       (1 + 4 + 1 + sizeof(struct ecryptfs_message)),
			       count);
			goto out_free;
		}
		memcpy(&counter_nbo, &data[i], 4);
		seq = be32_to_cpu(counter_nbo);
		i += 4;
		rc = ecryptfs_parse_packet_length(&data[i], &packet_size,
						  &packet_size_length);
		if (rc) {
			printk(KERN_WARNING "%s: Error parsing packet length; "
			       "rc = [%d]\n", __func__, rc);
			goto out_free;
		}
		i += packet_size_length;
		if ((1 + 4 + packet_size_length + packet_size) != count) {
			printk(KERN_WARNING "%s: (1 + packet_size_length([%Zd])"
			       " + packet_size([%Zd]))([%Zd]) != "
			       "count([%Zd]). Invalid packet format.\n",
			       __func__, packet_size_length, packet_size,
			       (1 + packet_size_length + packet_size), count);
			goto out_free;
		}
		rc = ecryptfs_miscdev_response(&data[i], packet_size,
					       current->euid,
					       current->nsproxy->user_ns,
					       task_pid(current), seq);
		if (rc)
			printk(KERN_WARNING "%s: Failed to deliver miscdev "
			       "response to requesting operation; rc = [%d]\n",
			       __func__, rc);
		break;
	case ECRYPTFS_MSG_HELO:
		rc = ecryptfs_miscdev_helo(current->euid,
					   current->nsproxy->user_ns,
					   task_pid(current));
		if (rc) {
			printk(KERN_ERR "%s: Error attempting to process "
			       "helo from pid [0x%p]; rc = [%d]\n", __func__,
			       task_pid(current), rc);
			goto out_free;
		}
		break;
	case ECRYPTFS_MSG_QUIT:
		rc = ecryptfs_miscdev_quit(current->euid,
					   current->nsproxy->user_ns,
					   task_pid(current));
		if (rc) {
			printk(KERN_ERR "%s: Error attempting to process "
			       "quit from pid [0x%p]; rc = [%d]\n", __func__,
			       task_pid(current), rc);
			goto out_free;
		}
		break;
	default:
		ecryptfs_printk(KERN_WARNING, "Dropping miscdev "
				"message of unrecognized type [%d]\n",
				data[0]);
		break;
	}
out_free:
	kfree(data);
out:
	return sz;
}
コード例 #27
0
ファイル: n_r3964.c プロジェクト: AlexShiLucky/linux
static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
			  unsigned char __user * buf, size_t nr)
{
	struct r3964_info *pInfo = tty->disc_data;
	struct r3964_client_info *pClient;
	struct r3964_message *pMsg;
	struct r3964_client_message theMsg;
	int ret;

	TRACE_L("read()");

	/*
	 *	Internal serialization of reads.
	 */
	if (file->f_flags & O_NONBLOCK) {
		if (!mutex_trylock(&pInfo->read_lock))
			return -EAGAIN;
	} else {
		if (mutex_lock_interruptible(&pInfo->read_lock))
			return -ERESTARTSYS;
	}

	pClient = findClient(pInfo, task_pid(current));
	if (pClient) {
		pMsg = remove_msg(pInfo, pClient);
		if (pMsg == NULL) {
			/* no messages available. */
			if (tty_io_nonblock(tty, file)) {
				ret = -EAGAIN;
				goto unlock;
			}
			/* block until there is a message: */
			wait_event_interruptible(tty->read_wait,
					(pMsg = remove_msg(pInfo, pClient)));
		}

		/* If we still haven't got a message, we must have been signalled */

		if (!pMsg) {
			ret = -EINTR;
			goto unlock;
		}

		/* deliver msg to client process: */
		theMsg.msg_id = pMsg->msg_id;
		theMsg.arg = pMsg->arg;
		theMsg.error_code = pMsg->error_code;
		ret = sizeof(struct r3964_client_message);

		kfree(pMsg);
		TRACE_M("r3964_read - msg kfree %p", pMsg);

		if (copy_to_user(buf, &theMsg, ret)) {
			ret = -EFAULT;
			goto unlock;
		}

		TRACE_PS("read - return %d", ret);
		goto unlock;
	}
	ret = -EPERM;
unlock:
	mutex_unlock(&pInfo->read_lock);
	return ret;
}
コード例 #28
0
/**
 * ecryptfs_miscdev_write - handle write to daemon miscdev handle
 * @file: File for misc dev handle (ignored)
 * @buf: Buffer containing user data
 * @count: Amount of data in @buf
 * @ppos: Pointer to offset in file (ignored)
 *
 * miscdevfs packet format:
 *  Octet 0: Type
 *  Octets 1-4: network byte order msg_ctx->counter (0's for non-response)
 *  Octets 5-N0: Size of struct ecryptfs_message to follow
 *  Octets N0-N1: struct ecryptfs_message (including data)
 *
 * Returns the number of bytes read from @buf
 */
static ssize_t
ecryptfs_miscdev_write(struct file *file, const char __user *buf,
		       size_t count, loff_t *ppos)
{
	__be32 counter_nbo;
	u32 seq;
	size_t packet_size, packet_size_length, i;
	ssize_t sz = 0;
	char *data;
	uid_t euid = current_euid();
	int rc;

	if (count == 0)
		goto out;

	data = memdup_user(buf, count);
	if (IS_ERR(data)) {
		printk(KERN_ERR "%s: memdup_user returned error [%ld]\n",
		       __func__, PTR_ERR(data));
		goto out;
	}
	sz = count;
	i = 0;
	switch (data[i++]) {
	case ECRYPTFS_MSG_RESPONSE:
		if (count < (1 + 4 + 1 + sizeof(struct ecryptfs_message))) {
			printk(KERN_WARNING "%s: Minimum acceptable packet "
			       "size is [%zd], but amount of data written is "
			       "only [%zd]. Discarding response packet.\n",
			       __func__,
			       (1 + 4 + 1 + sizeof(struct ecryptfs_message)),
			       count);
			goto out_free;
		}
		memcpy(&counter_nbo, &data[i], 4);
		seq = be32_to_cpu(counter_nbo);
		i += 4;
		rc = ecryptfs_parse_packet_length(&data[i], &packet_size,
						  &packet_size_length);
		if (rc) {
			printk(KERN_WARNING "%s: Error parsing packet length; "
			       "rc = [%d]\n", __func__, rc);
			goto out_free;
		}
		i += packet_size_length;
		if ((1 + 4 + packet_size_length + packet_size) != count) {
			printk(KERN_WARNING "%s: (1 + packet_size_length([%zd])"
			       " + packet_size([%zd]))([%zd]) != "
			       "count([%zd]). Invalid packet format.\n",
			       __func__, packet_size_length, packet_size,
			       (1 + packet_size_length + packet_size), count);
			goto out_free;
		}
		rc = ecryptfs_miscdev_response(&data[i], packet_size,
					       euid, current_user_ns(),
					       task_pid(current), seq);
		if (rc)
			printk(KERN_WARNING "%s: Failed to deliver miscdev "
			       "response to requesting operation; rc = [%d]\n",
			       __func__, rc);
		break;
	case ECRYPTFS_MSG_CLEARMASTER_BLACK:
		printk(KERN_DEBUG "Clear the master key with blacklist");
		break;
	case ECRYPTFS_MSG_HELO:
	case ECRYPTFS_MSG_QUIT:
		break;
	default:
		ecryptfs_printk(KERN_WARNING, "Dropping miscdev "
				"message of unrecognized type [%d]\n",
				data[0]);
		break;
	}
out_free:
	kfree(data);
out:
	return sz;
}
コード例 #29
0
static int __init kernel_init(void * unused)
{
	/*
	 * Wait until kthreadd is all set-up.
	 */
	wait_for_completion(&kthreadd_done);
	lock_kernel();

	/*
	 * init can allocate pages on any node
	 */
	set_mems_allowed(node_states[N_HIGH_MEMORY]);
	/*
	 * init can run on any cpu.
	 */
	set_cpus_allowed_ptr(current, cpu_all_mask);
	/*
	 * Tell the world that we're going to be the grim
	 * reaper of innocent orphaned children.
	 *
	 * We don't want people to have to make incorrect
	 * assumptions about where in the task array this
	 * can be found.
	 */
	init_pid_ns.child_reaper = current;

	cad_pid = task_pid(current);

	smp_prepare_cpus(setup_max_cpus);

	do_pre_smp_initcalls();
	start_boot_trace();

	smp_init();
	sched_init_smp();

	do_basic_setup();

	/* Open the /dev/console on the rootfs, this should never fail */
	if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
		printk(KERN_WARNING "Warning: unable to open an initial console.\n");

	(void) sys_dup(0);
	(void) sys_dup(0);
	/*
	 * check if there is an early userspace init.  If yes, let it do all
	 * the work
	 */

	if (!ramdisk_execute_command)
		ramdisk_execute_command = "/init";

	if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
		ramdisk_execute_command = NULL;
		prepare_namespace();
	}

	/*
	 * Ok, we have completed the initial bootup, and
	 * we're essentially up and running. Get rid of the
	 * initmem segments and start the user-mode stuff..
	 */

	init_post();
	return 0;
}
コード例 #30
0
int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
{
	struct dnotify_struct *dn;
	struct dnotify_struct *odn;
	struct dnotify_struct **prev;
	struct inode *inode;
	fl_owner_t id = current->files;
	struct file *f;
	int error = 0;

	if ((arg & ~DN_MULTISHOT) == 0) {
		dnotify_flush(filp, id);
		return 0;
	}
	if (!dir_notify_enable)
		return -EINVAL;
	inode = filp->f_path.dentry->d_inode;
	if (!S_ISDIR(inode->i_mode))
		return -ENOTDIR;
	dn = kmem_cache_alloc(dn_cache, GFP_KERNEL);
	if (dn == NULL)
		return -ENOMEM;
	spin_lock(&inode->i_lock);
	prev = &inode->i_dnotify;
	while ((odn = *prev) != NULL) {
		if ((odn->dn_owner == id) && (odn->dn_filp == filp)) {
			odn->dn_fd = fd;
			odn->dn_mask |= arg;
			inode->i_dnotify_mask |= arg & ~DN_MULTISHOT;
			goto out_free;
		}
		prev = &odn->dn_next;
	}

	rcu_read_lock();
	f = fcheck(fd);
	rcu_read_unlock();
	/* we'd lost the race with close(), sod off silently */
	/* note that inode->i_lock prevents reordering problems
	 * between accesses to descriptor table and ->i_dnotify */
	if (f != filp)
		goto out_free;

	error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
	if (error)
		goto out_free;

	dn->dn_mask = arg;
	dn->dn_fd = fd;
	dn->dn_filp = filp;
	dn->dn_owner = id;
	inode->i_dnotify_mask |= arg & ~DN_MULTISHOT;
	dn->dn_next = inode->i_dnotify;
	inode->i_dnotify = dn;
	spin_unlock(&inode->i_lock);
	return 0;

out_free:
	spin_unlock(&inode->i_lock);
	kmem_cache_free(dn_cache, dn);
	return error;
}