1*4882a593Smuzhiyun // SPDX-License-Identifier: LGPL-2.1
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * trace/beauty/mount_flags.c
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2018, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include "trace/beauty/beauty.h"
9*4882a593Smuzhiyun #include <linux/compiler.h>
10*4882a593Smuzhiyun #include <linux/kernel.h>
11*4882a593Smuzhiyun #include <linux/log2.h>
12*4882a593Smuzhiyun #include <sys/mount.h>
13*4882a593Smuzhiyun
mount__scnprintf_flags(unsigned long flags,char * bf,size_t size,bool show_prefix)14*4882a593Smuzhiyun static size_t mount__scnprintf_flags(unsigned long flags, char *bf, size_t size, bool show_prefix)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun #include "trace/beauty/generated/mount_flags_array.c"
17*4882a593Smuzhiyun static DEFINE_STRARRAY(mount_flags, "MS_");
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun return strarray__scnprintf_flags(&strarray__mount_flags, bf, size, show_prefix, flags);
20*4882a593Smuzhiyun }
21*4882a593Smuzhiyun
syscall_arg__mask_val_mount_flags(struct syscall_arg * arg __maybe_unused,unsigned long flags)22*4882a593Smuzhiyun unsigned long syscall_arg__mask_val_mount_flags(struct syscall_arg *arg __maybe_unused, unsigned long flags)
23*4882a593Smuzhiyun {
24*4882a593Smuzhiyun // do_mount in fs/namespace.c:
25*4882a593Smuzhiyun /*
26*4882a593Smuzhiyun * Pre-0.97 versions of mount() didn't have a flags word. When the
27*4882a593Smuzhiyun * flags word was introduced its top half was required to have the
28*4882a593Smuzhiyun * magic value 0xC0ED, and this remained so until 2.4.0-test9.
29*4882a593Smuzhiyun * Therefore, if this magic number is present, it carries no
30*4882a593Smuzhiyun * information and must be discarded.
31*4882a593Smuzhiyun */
32*4882a593Smuzhiyun if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
33*4882a593Smuzhiyun flags &= ~MS_MGC_MSK;
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun return flags;
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun
syscall_arg__scnprintf_mount_flags(char * bf,size_t size,struct syscall_arg * arg)38*4882a593Smuzhiyun size_t syscall_arg__scnprintf_mount_flags(char *bf, size_t size, struct syscall_arg *arg)
39*4882a593Smuzhiyun {
40*4882a593Smuzhiyun unsigned long flags = arg->val;
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun return mount__scnprintf_flags(flags, bf, size, arg->show_string_prefix);
43*4882a593Smuzhiyun }
44