linux-imx

// SPDX-License-Identifier: GPL-2.0

#include <linux/fs.h>

#include <linux/sched.h>

#include <linux/slab.h>

#include "internal.h"

#include "mount.h"

​

static DEFINE_SPINLOCK(pin_lock);

​

void pin_remove(struct fs_pin *pin)

{

    spin_lock(&pin_lock);

    hlist_del_init(&pin->m_list);

    hlist_del_init(&pin->s_list);

    spin_unlock(&pin_lock);

    spin_lock_irq(&pin->wait.lock);

    pin->done = 1;

    wake_up_locked(&pin->wait);

    spin_unlock_irq(&pin->wait.lock);

}

​

void pin_insert_group(struct fs_pin *pin, struct vfsmount *m, struct hlist_head *p)

{

    spin_lock(&pin_lock);

    if (p)

        hlist_add_head(&pin->s_list, p);

    hlist_add_head(&pin->m_list, &real_mount(m)->mnt_pins);

    spin_unlock(&pin_lock);

}

​

void pin_insert(struct fs_pin *pin, struct vfsmount *m)

{

    pin_insert_group(pin, m, &m->mnt_sb->s_pins);

}

​

void pin_kill(struct fs_pin *p)

{

    wait_queue_entry_t wait;

​

    if (!p) {

        rcu_read_unlock();

        return;

    }

    init_wait(&wait);

    spin_lock_irq(&p->wait.lock);

    if (likely(!p->done)) {

        p->done = -1;

        spin_unlock_irq(&p->wait.lock);

        rcu_read_unlock();

        p->kill(p);

        return;

    }

    if (p->done > 0) {

        spin_unlock_irq(&p->wait.lock);

        rcu_read_unlock();

        return;

    }

    __add_wait_queue(&p->wait, &wait);

    while (1) {

        set_current_state(TASK_UNINTERRUPTIBLE);

        spin_unlock_irq(&p->wait.lock);

        rcu_read_unlock();

        schedule();