-/**
- * lock_may_read - checks that the region is free of locks
- * @inode: the inode that is being read
- * @start: the first byte to read
- * @len: the number of bytes to read
- *
- * Emulates Windows locking requirements. Whole-file
- * mandatory locks (share modes) can prohibit a read and
- * byte-range POSIX locks can prohibit a read if they overlap.
- *
- * N.B. this function is only ever called
- * from knfsd and ownership of locks is never checked.
- */
-int lock_may_read(struct inode *inode, loff_t start, unsigned long len)
-{
- struct file_lock *fl;
- int result = 1;
-
- spin_lock(&inode->i_lock);
- for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
- if (IS_POSIX(fl)) {
- if (fl->fl_type == F_RDLCK)
- continue;
- if ((fl->fl_end < start) || (fl->fl_start > (start + len)))
- continue;
- } else if (IS_FLOCK(fl)) {
- if (!(fl->fl_type & LOCK_MAND))
- continue;
- if (fl->fl_type & LOCK_READ)
- continue;
- } else
- continue;
- result = 0;
- break;
- }
- spin_unlock(&inode->i_lock);
- return result;
-}
-
-EXPORT_SYMBOL(lock_may_read);
-
-/**
- * lock_may_write - checks that the region is free of locks
- * @inode: the inode that is being written
- * @start: the first byte to write
- * @len: the number of bytes to write
- *
- * Emulates Windows locking requirements. Whole-file
- * mandatory locks (share modes) can prohibit a write and
- * byte-range POSIX locks can prohibit a write if they overlap.
- *
- * N.B. this function is only ever called
- * from knfsd and ownership of locks is never checked.
- */
-int lock_may_write(struct inode *inode, loff_t start, unsigned long len)
-{
- struct file_lock *fl;
- int result = 1;
-
- spin_lock(&inode->i_lock);
- for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
- if (IS_POSIX(fl)) {
- if ((fl->fl_end < start) || (fl->fl_start > (start + len)))
- continue;
- } else if (IS_FLOCK(fl)) {
- if (!(fl->fl_type & LOCK_MAND))
- continue;
- if (fl->fl_type & LOCK_WRITE)
- continue;
- } else
- continue;
- result = 0;
- break;
- }
- spin_unlock(&inode->i_lock);
- return result;
-}
-
-EXPORT_SYMBOL(lock_may_write);
-