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#ifndef _LINUX_LOCKS_H
#define _LINUX_LOCKS_H
#ifndef _LINUX_MM_H
#include <linux/mm.h>
#endif
#ifndef _LINUX_PAGEMAP_H
#include <linux/pagemap.h>
#endif
/*
* Buffer cache locking - note that interrupts may only unlock, not
* lock buffers.
*/
extern void __wait_on_buffer(struct buffer_head *);
extern inline void wait_on_buffer(struct buffer_head * bh)
{
if (test_bit(BH_Lock, &bh->b_state))
__wait_on_buffer(bh);
}
extern inline void lock_buffer(struct buffer_head * bh)
{
while (test_and_set_bit(BH_Lock, &bh->b_state))
__wait_on_buffer(bh);
}
extern inline void unlock_buffer(struct buffer_head *bh)
{
clear_bit(BH_Lock, &bh->b_state);
smp_mb__after_clear_bit();
if (waitqueue_active(&bh->b_wait))
wake_up(&bh->b_wait);
}
/*
* super-block locking. Again, interrupts may only unlock
* a super-block (although even this isn't done right now.
* nfs may need it).
*/
extern void __wait_on_super(struct super_block *);
extern inline void wait_on_super(struct super_block * sb)
{
if (sb->s_lock)
__wait_on_super(sb);
}
extern inline void lock_super(struct super_block * sb)
{
if (sb->s_lock)
__wait_on_super(sb);
sb->s_lock = 1;
}
extern inline void unlock_super(struct super_block * sb)
{
sb->s_lock = 0;
/*
* No need of any barrier, we're protected by
* the big kernel lock here... unfortunately :)
*/
if (waitqueue_active(&sb->s_wait))
wake_up(&sb->s_wait);
}
#endif /* _LINUX_LOCKS_H */
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