xref: /openbmc/linux/fs/notify/fdinfo.c (revision eb3fcf00)
1 #include <linux/file.h>
2 #include <linux/fs.h>
3 #include <linux/fsnotify_backend.h>
4 #include <linux/idr.h>
5 #include <linux/init.h>
6 #include <linux/inotify.h>
7 #include <linux/fanotify.h>
8 #include <linux/kernel.h>
9 #include <linux/namei.h>
10 #include <linux/sched.h>
11 #include <linux/types.h>
12 #include <linux/seq_file.h>
13 #include <linux/proc_fs.h>
14 #include <linux/exportfs.h>
15 
16 #include "inotify/inotify.h"
17 #include "../fs/mount.h"
18 
19 #if defined(CONFIG_PROC_FS)
20 
21 #if defined(CONFIG_INOTIFY_USER) || defined(CONFIG_FANOTIFY)
22 
23 static void show_fdinfo(struct seq_file *m, struct file *f,
24 			void (*show)(struct seq_file *m,
25 				     struct fsnotify_mark *mark))
26 {
27 	struct fsnotify_group *group = f->private_data;
28 	struct fsnotify_mark *mark;
29 
30 	mutex_lock(&group->mark_mutex);
31 	list_for_each_entry(mark, &group->marks_list, g_list) {
32 		show(m, mark);
33 		if (seq_has_overflowed(m))
34 			break;
35 	}
36 	mutex_unlock(&group->mark_mutex);
37 }
38 
39 #if defined(CONFIG_EXPORTFS)
40 static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
41 {
42 	struct {
43 		struct file_handle handle;
44 		u8 pad[MAX_HANDLE_SZ];
45 	} f;
46 	int size, ret, i;
47 
48 	f.handle.handle_bytes = sizeof(f.pad);
49 	size = f.handle.handle_bytes >> 2;
50 
51 	ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, 0);
52 	if ((ret == FILEID_INVALID) || (ret < 0)) {
53 		WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret);
54 		return;
55 	}
56 
57 	f.handle.handle_type = ret;
58 	f.handle.handle_bytes = size * sizeof(u32);
59 
60 	seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
61 		   f.handle.handle_bytes, f.handle.handle_type);
62 
63 	for (i = 0; i < f.handle.handle_bytes; i++)
64 		seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
65 }
66 #else
67 static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
68 {
69 }
70 #endif
71 
72 #ifdef CONFIG_INOTIFY_USER
73 
74 static void inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
75 {
76 	struct inotify_inode_mark *inode_mark;
77 	struct inode *inode;
78 
79 	if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE) ||
80 	    !(mark->flags & FSNOTIFY_MARK_FLAG_INODE))
81 		return;
82 
83 	inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark);
84 	inode = igrab(mark->inode);
85 	if (inode) {
86 		seq_printf(m, "inotify wd:%x ino:%lx sdev:%x mask:%x ignored_mask:%x ",
87 			   inode_mark->wd, inode->i_ino, inode->i_sb->s_dev,
88 			   mark->mask, mark->ignored_mask);
89 		show_mark_fhandle(m, inode);
90 		seq_putc(m, '\n');
91 		iput(inode);
92 	}
93 }
94 
95 void inotify_show_fdinfo(struct seq_file *m, struct file *f)
96 {
97 	show_fdinfo(m, f, inotify_fdinfo);
98 }
99 
100 #endif /* CONFIG_INOTIFY_USER */
101 
102 #ifdef CONFIG_FANOTIFY
103 
104 static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
105 {
106 	unsigned int mflags = 0;
107 	struct inode *inode;
108 
109 	if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE))
110 		return;
111 
112 	if (mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)
113 		mflags |= FAN_MARK_IGNORED_SURV_MODIFY;
114 
115 	if (mark->flags & FSNOTIFY_MARK_FLAG_INODE) {
116 		inode = igrab(mark->inode);
117 		if (!inode)
118 			return;
119 		seq_printf(m, "fanotify ino:%lx sdev:%x mflags:%x mask:%x ignored_mask:%x ",
120 			   inode->i_ino, inode->i_sb->s_dev,
121 			   mflags, mark->mask, mark->ignored_mask);
122 		show_mark_fhandle(m, inode);
123 		seq_putc(m, '\n');
124 		iput(inode);
125 	} else if (mark->flags & FSNOTIFY_MARK_FLAG_VFSMOUNT) {
126 		struct mount *mnt = real_mount(mark->mnt);
127 
128 		seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n",
129 			   mnt->mnt_id, mflags, mark->mask, mark->ignored_mask);
130 	}
131 }
132 
133 void fanotify_show_fdinfo(struct seq_file *m, struct file *f)
134 {
135 	struct fsnotify_group *group = f->private_data;
136 	unsigned int flags = 0;
137 
138 	switch (group->priority) {
139 	case FS_PRIO_0:
140 		flags |= FAN_CLASS_NOTIF;
141 		break;
142 	case FS_PRIO_1:
143 		flags |= FAN_CLASS_CONTENT;
144 		break;
145 	case FS_PRIO_2:
146 		flags |= FAN_CLASS_PRE_CONTENT;
147 		break;
148 	}
149 
150 	if (group->max_events == UINT_MAX)
151 		flags |= FAN_UNLIMITED_QUEUE;
152 
153 	if (group->fanotify_data.max_marks == UINT_MAX)
154 		flags |= FAN_UNLIMITED_MARKS;
155 
156 	seq_printf(m, "fanotify flags:%x event-flags:%x\n",
157 		   flags, group->fanotify_data.f_flags);
158 
159 	show_fdinfo(m, f, fanotify_fdinfo);
160 }
161 
162 #endif /* CONFIG_FANOTIFY */
163 
164 #endif /* CONFIG_INOTIFY_USER || CONFIG_FANOTIFY */
165 
166 #endif /* CONFIG_PROC_FS */
167