src/common/ns.h

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2019 Michael Jeanson <mjeanson@efficios.com>
   5  */
   6
   7 #ifndef _LTTNG_NS_H
   8 #define _LTTNG_NS_H
   9
  10 /*
  11  * The lowest valid inode number that can be allocated in the proc filesystem
  12  * is 0xF0000000. Any number below can be used internally as an error code.
  13  *
  14  * Zero is used in the kernel as an error code, it's the value we will return
  15  * when we fail to read the proper inode number.
  16  *
  17  * One is used internally to identify an uninitialized cache entry, it should
  18  * never be returned.
  19  */
  20
  21 enum ns_ino_state {
  22         NS_INO_UNAVAILABLE      = 0x0,
  23         NS_INO_UNINITIALIZED    = 0x1,
  24         NS_INO_MIN              = 0xF0000000,
  25 };
  26
  27 /*
  28  * The longest possible namespace proc path is with the cgroup ns
  29  * and the maximum theoretical linux pid of 536870912 :
  30  *
  31  *  /proc/self/task/536870912/ns/cgroup
  32  */
  33 #define LTTNG_PROC_NS_PATH_MAX 40
  34
  35 #endif /* _LTTNG_NS_H */