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// SPDX-License-Identifier: GPL-2.0
#include <linux/init_task.h>
#include <linux/export.h>
#include <linux/mqueue.h>
#include <linux/sched.h>
#include <linux/sched/sysctl.h>
#include <linux/sched/rt.h>
#include <linux/sched/task.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/audit.h>

#include <asm/pgtable.h>
#include <linux/uaccess.h>

static struct signal_struct init_signals = {
	.nr_threads	= 1,
	.thread_head	= LIST_HEAD_INIT(init_task.thread_node),
	.wait_chldexit	= __WAIT_QUEUE_HEAD_INITIALIZER(init_signals.wait_chldexit),
	.shared_pending	= {
		.list = LIST_HEAD_INIT(init_signals.shared_pending.list),
		.signal =  {{0}}
	},
	.rlim		= INIT_RLIMITS,
	.cred_guard_mutex = __MUTEX_INITIALIZER(init_signals.cred_guard_mutex),
#ifdef CONFIG_POSIX_TIMERS
	.posix_timers = LIST_HEAD_INIT(init_signals.posix_timers),
	.cputimer	= {
		.cputime_atomic	= INIT_CPUTIME_ATOMIC,
		.running	= false,
		.checking_timer = false,
	},
#endif
	INIT_CPU_TIMERS(init_signals)
	INIT_PREV_CPUTIME(init_signals)
};

static struct sighand_struct init_sighand = {
	.count		= ATOMIC_INIT(1),
	.action		= { { { .sa_handler = SIG_DFL, } }, },
	.siglock	= __SPIN_LOCK_UNLOCKED(init_sighand.siglock),
	.signalfd_wqh	= __WAIT_QUEUE_HEAD_INITIALIZER(init_sighand.signalfd_wqh),
};

/*
 * Set up the first task table, touch at your own risk!. Base=0,
 * limit=0x1fffff (=2MB)
 */
struct task_struct init_task
#ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK
	__init_task_data
#endif
= {
#ifdef CONFIG_THREAD_INFO_IN_TASK
	.thread_info	= INIT_THREAD_INFO(init_task),
	.stack_refcount	= ATOMIC_INIT(1),
#endif
	.state		= 0,
	.stack		= init_stack,
	.usage		= ATOMIC_INIT(2),
	.flags		= PF_KTHREAD,
	.prio		= MAX_PRIO - 20,
	.static_prio	= MAX_PRIO - 20,
	.normal_prio	= MAX_PRIO - 20,
	.policy		= SCHED_NORMAL,
	.cpus_allowed	= CPU_MASK_ALL,
	.nr_cpus_allowed= NR_CPUS,
	.mm		= NULL,
	.active_mm	= &init_mm,
	.restart_block	= {
		.fn = do_no_restart_syscall,
	},
	.se		= {
		.group_node 	= LIST_HEAD_INIT(init_task.se.group_node),
	},
	.rt		= {
		.run_list	= LIST_HEAD_INIT(init_task.rt.run_list),
		.time_slice	= RR_TIMESLICE,
	},
	.tasks		= LIST_HEAD_INIT(init_task.tasks),
#ifdef CONFIG_SMP
	.pushable_tasks	= PLIST_NODE_INIT(init_task.pushable_tasks, MAX_PRIO),
#endif
#ifdef CONFIG_CGROUP_SCHED
	.sched_task_group = &root_task_group,
#endif
	.ptraced	= LIST_HEAD_INIT(init_task.ptraced),
	.ptrace_entry	= LIST_HEAD_INIT(init_task.ptrace_entry),
	.real_parent	= &init_task,
	.parent		= &init_task,
	.children	= LIST_HEAD_INIT(init_task.children),
	.sibling	= LIST_HEAD_INIT(init_task.sibling),
	.group_leader	= &init_task,
	RCU_POINTER_INITIALIZER(real_cred, &init_cred),
	RCU_POINTER_INITIALIZER(cred, &init_cred),
	.comm		= INIT_TASK_COMM,
	.thread		= INIT_THREAD,
	.fs		= &init_fs,
	.files		= &init_files,
	.signal		= &init_signals,
	.sighand	= &init_sighand,
	.nsproxy	= &init_nsproxy,
	.pending	= {
		.list = LIST_HEAD_INIT(init_task.pending.list),
		.signal = {{0}}
	},
	.blocked	= {{0}},
	.alloc_lock	= __SPIN_LOCK_UNLOCKED(init_task.alloc_lock),
	.journal_info	= NULL,
	INIT_CPU_TIMERS(init_task)
	.pi_lock	= __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
	.timer_slack_ns = 50000, /* 50 usec default slack */
	.pids = {
		[PIDTYPE_PID]  = INIT_PID_LINK(PIDTYPE_PID),
		[PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID),
		[PIDTYPE_SID]  = INIT_PID_LINK(PIDTYPE_SID),
	},
	.thread_group	= LIST_HEAD_INIT(init_task.thread_group),
	.thread_node	= LIST_HEAD_INIT(init_signals.thread_head),
#ifdef CONFIG_AUDITSYSCALL
	.loginuid	= INVALID_UID,
	.sessionid	= AUDIT_SID_UNSET,
#endif
#ifdef CONFIG_PERF_EVENTS
	.perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex),
	.perf_event_list = LIST_HEAD_INIT(init_task.perf_event_list),
#endif
#ifdef CONFIG_PREEMPT_RCU
	.rcu_read_lock_nesting = 0,
	.rcu_read_unlock_special.s = 0,
	.rcu_node_entry = LIST_HEAD_INIT(init_task.rcu_node_entry),
	.rcu_blocked_node = NULL,
#endif
#ifdef CONFIG_TASKS_RCU
	.rcu_tasks_holdout = false,
	.rcu_tasks_holdout_list = LIST_HEAD_INIT(init_task.rcu_tasks_holdout_list),
	.rcu_tasks_idle_cpu = -1,
#endif
#ifdef CONFIG_CPUSETS
	.mems_allowed_seq = SEQCNT_ZERO(init_task.mems_allowed_seq),
#endif
#ifdef CONFIG_RT_MUTEXES
	.pi_waiters	= RB_ROOT_CACHED,
	.pi_top_task	= NULL,
#endif
	INIT_PREV_CPUTIME(init_task)
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
	.vtime.seqcount	= SEQCNT_ZERO(init_task.vtime_seqcount),
	.vtime.starttime = 0,
	.vtime.state	= VTIME_SYS,
#endif
#ifdef CONFIG_NUMA_BALANCING
	.numa_preferred_nid = -1,
	.numa_group	= NULL,
	.numa_faults	= NULL,
#endif
#ifdef CONFIG_KASAN
	.kasan_depth	= 1,
#endif
#ifdef CONFIG_TRACE_IRQFLAGS
	.softirqs_enabled = 1,
#endif
#ifdef CONFIG_LOCKDEP
	.lockdep_recursion = 0,
#endif
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
	.ret_stack	= NULL,
#endif
#if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPT)
	.trace_recursion = 0,
#endif
#ifdef CONFIG_LIVEPATCH
	.patch_state	= KLP_UNDEFINED,
#endif
#ifdef CONFIG_SECURITY
	.security	= NULL,
#endif
};
EXPORT_SYMBOL(init_task);

/*
 * Initial thread structure. Alignment of this is handled by a special
 * linker map entry.
 */
#ifndef CONFIG_THREAD_INFO_IN_TASK
struct thread_info init_thread_info __init_thread_info = INIT_THREAD_INFO(init_task);
#endif
="p">{ int error; if (!try_module_get(scsi_dh->module)) return -EINVAL; error = scsi_dh->attach(sdev); if (error) { sdev_printk(KERN_ERR, sdev, "%s: Attach failed (%d)\n", scsi_dh->name, error); module_put(scsi_dh->module); } else sdev->handler = scsi_dh; return error; } /* * scsi_dh_handler_detach - Detach a device handler from a device * @sdev - SCSI device the device handler should be detached from */ static void scsi_dh_handler_detach(struct scsi_device *sdev) { sdev->handler->detach(sdev); sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", sdev->handler->name); module_put(sdev->handler->module); } int scsi_dh_add_device(struct scsi_device *sdev) { struct scsi_device_handler *devinfo = NULL; const char *drv; int err = 0; drv = scsi_dh_find_driver(sdev); if (drv) devinfo = __scsi_dh_lookup(drv); if (devinfo) err = scsi_dh_handler_attach(sdev, devinfo); return err; } void scsi_dh_release_device(struct scsi_device *sdev) { if (sdev->handler) scsi_dh_handler_detach(sdev); } /* * scsi_register_device_handler - register a device handler personality * module. * @scsi_dh - device handler to be registered. * * Returns 0 on success, -EBUSY if handler already registered. */ int scsi_register_device_handler(struct scsi_device_handler *scsi_dh) { if (__scsi_dh_lookup(scsi_dh->name)) return -EBUSY; if (!scsi_dh->attach || !scsi_dh->detach) return -EINVAL; spin_lock(&list_lock); list_add(&scsi_dh->list, &scsi_dh_list); spin_unlock(&list_lock); printk(KERN_INFO "%s: device handler registered\n", scsi_dh->name); return SCSI_DH_OK; } EXPORT_SYMBOL_GPL(scsi_register_device_handler); /* * scsi_unregister_device_handler - register a device handler personality * module. * @scsi_dh - device handler to be unregistered. * * Returns 0 on success, -ENODEV if handler not registered. */ int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh) { if (!__scsi_dh_lookup(scsi_dh->name)) return -ENODEV; spin_lock(&list_lock); list_del(&scsi_dh->list); spin_unlock(&list_lock); printk(KERN_INFO "%s: device handler unregistered\n", scsi_dh->name); return SCSI_DH_OK; } EXPORT_SYMBOL_GPL(scsi_unregister_device_handler); /* * scsi_dh_activate - activate the path associated with the scsi_device * corresponding to the given request queue. * Returns immediately without waiting for activation to be completed. * @q - Request queue that is associated with the scsi_device to be * activated. * @fn - Function to be called upon completion of the activation. * Function fn is called with data (below) and the error code. * Function fn may be called from the same calling context. So, * do not hold the lock in the caller which may be needed in fn. * @data - data passed to the function fn upon completion. * */ int scsi_dh_activate(struct request_queue *q, activate_complete fn, void *data) { struct scsi_device *sdev; int err = SCSI_DH_NOSYS; sdev = scsi_device_from_queue(q); if (!sdev) { if (fn) fn(data, err); return err; } if (!sdev->handler) goto out_fn; err = SCSI_DH_NOTCONN; if (sdev->sdev_state == SDEV_CANCEL || sdev->sdev_state == SDEV_DEL) goto out_fn; err = SCSI_DH_DEV_OFFLINED; if (sdev->sdev_state == SDEV_OFFLINE) goto out_fn; if (sdev->handler->activate) err = sdev->handler->activate(sdev, fn, data); out_put_device: put_device(&sdev->sdev_gendev); return err; out_fn: if (fn) fn(data, err); goto out_put_device; } EXPORT_SYMBOL_GPL(scsi_dh_activate); /* * scsi_dh_set_params - set the parameters for the device as per the * string specified in params. * @q - Request queue that is associated with the scsi_device for * which the parameters to be set. * @params - parameters in the following format * "no_of_params\0param1\0param2\0param3\0...\0" * for example, string for 2 parameters with value 10 and 21 * is specified as "2\010\021\0". */ int scsi_dh_set_params(struct request_queue *q, const char *params) { struct scsi_device *sdev; int err = -SCSI_DH_NOSYS; sdev = scsi_device_from_queue(q); if (!sdev) return err; if (sdev->handler && sdev->handler->set_params) err = sdev->handler->set_params(sdev, params); put_device(&sdev->sdev_gendev); return err; } EXPORT_SYMBOL_GPL(scsi_dh_set_params); /* * scsi_dh_attach - Attach device handler * @q - Request queue that is associated with the scsi_device * the handler should be attached to * @name - name of the handler to attach */ int scsi_dh_attach(struct request_queue *q, const char *name) { struct scsi_device *sdev; struct scsi_device_handler *scsi_dh; int err = 0; sdev = scsi_device_from_queue(q); if (!sdev) return -ENODEV; scsi_dh = scsi_dh_lookup(name); if (!scsi_dh) { err = -EINVAL; goto out_put_device; } if (sdev->handler) { if (sdev->handler != scsi_dh) err = -EBUSY; goto out_put_device; } err = scsi_dh_handler_attach(sdev, scsi_dh); out_put_device: put_device(&sdev->sdev_gendev); return err; } EXPORT_SYMBOL_GPL(scsi_dh_attach); /* * scsi_dh_attached_handler_name - Get attached device handler's name * @q - Request queue that is associated with the scsi_device * that may have a device handler attached * @gfp - the GFP mask used in the kmalloc() call when allocating memory * * Returns name of attached handler, NULL if no handler is attached. * Caller must take care to free the returned string. */ const char *scsi_dh_attached_handler_name(struct request_queue *q, gfp_t gfp) { struct scsi_device *sdev; const char *handler_name = NULL; sdev = scsi_device_from_queue(q); if (!sdev) return NULL; if (sdev->handler) handler_name = kstrdup(sdev->handler->name, gfp); put_device(&sdev->sdev_gendev); return handler_name; } EXPORT_SYMBOL_GPL(scsi_dh_attached_handler_name);