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