Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) #include "internal.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include "mount.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) static DEFINE_SPINLOCK(pin_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) void pin_remove(struct fs_pin *pin)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) 	spin_lock(&pin_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 	hlist_del_init(&pin->m_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 	hlist_del_init(&pin->s_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 	spin_unlock(&pin_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 	spin_lock_irq(&pin->wait.lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	pin->done = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	wake_up_locked(&pin->wait);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 	spin_unlock_irq(&pin->wait.lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) void pin_insert(struct fs_pin *pin, struct vfsmount *m)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 	spin_lock(&pin_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	hlist_add_head(&pin->s_list, &m->mnt_sb->s_pins);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	hlist_add_head(&pin->m_list, &real_mount(m)->mnt_pins);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	spin_unlock(&pin_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) void pin_kill(struct fs_pin *p)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	wait_queue_entry_t wait;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	if (!p) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	init_wait(&wait);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	spin_lock_irq(&p->wait.lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	if (likely(!p->done)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 		p->done = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 		spin_unlock_irq(&p->wait.lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 		p->kill(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	if (p->done > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 		spin_unlock_irq(&p->wait.lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 	__add_wait_queue(&p->wait, &wait);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 	while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 		set_current_state(TASK_UNINTERRUPTIBLE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 		spin_unlock_irq(&p->wait.lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 		schedule();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 		rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 		if (likely(list_empty(&wait.entry)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 		/* OK, we know p couldn't have been freed yet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 		spin_lock_irq(&p->wait.lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 		if (p->done > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 			spin_unlock_irq(&p->wait.lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) void mnt_pin_kill(struct mount *m)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 	while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 		struct hlist_node *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 		rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 		p = READ_ONCE(m->mnt_pins.first);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 		if (!p) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 			rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) 		pin_kill(hlist_entry(p, struct fs_pin, m_list));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) void group_pin_kill(struct hlist_head *p)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) 	while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) 		struct hlist_node *q;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 		rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) 		q = READ_ONCE(p->first);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) 		if (!q) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) 			rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) 		pin_kill(hlist_entry(q, struct fs_pin, s_list));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) }