fs/btrfs/rcu-string.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * Copyright (C) 2012 Red Hat.  All rights reserved.
0004  */
0005
0006 #ifndef BTRFS_RCU_STRING_H
0007 #define BTRFS_RCU_STRING_H
0008
0009 struct rcu_string {
0010     struct rcu_head rcu;
0011     char str[];
0012 };
0013
0014 static inline struct rcu_string *rcu_string_strdup(const char *src, gfp_t mask)
0015 {
0016     size_t len = strlen(src) + 1;
0017     struct rcu_string *ret = kzalloc(sizeof(struct rcu_string) +
0018                      (len * sizeof(char)), mask);
0019     if (!ret)
0020         return ret;
0021     strncpy(ret->str, src, len);
0022     return ret;
0023 }
0024
0025 static inline void rcu_string_free(struct rcu_string *str)
0026 {
0027     if (str)
0028         kfree_rcu(str, rcu);
0029 }
0030
0031 #define printk_in_rcu(fmt, ...) do {    \
0032     rcu_read_lock();        \
0033     printk(fmt, __VA_ARGS__);   \
0034     rcu_read_unlock();      \
0035 } while (0)
0036
0037 #define printk_ratelimited_in_rcu(fmt, ...) do {    \
0038     rcu_read_lock();                \
0039     printk_ratelimited(fmt, __VA_ARGS__);       \
0040     rcu_read_unlock();              \
0041 } while (0)
0042
0043 #define rcu_str_deref(rcu_str) ({               \
0044     struct rcu_string *__str = rcu_dereference(rcu_str);    \
0045     __str->str;                     \
0046 })
0047
0048 #endif