Commit be77196b authored by Cyrill Gorcunov's avatar Cyrill Gorcunov Committed by Linus Torvalds

fs, notify: add procfs fdinfo helper

This allow us to print out fsnotify details such as watchee inode, device,
mask and optionally a file handle.

For inotify objects if kernel compiled with exportfs support the output
will be

 | pos:	0
 | flags:	02000000
 | inotify wd:3 ino:9e7e sdev:800013 mask:800afce ignored_mask:0 fhandle-bytes:8 fhandle-type:1 f_handle:7e9e0000640d1b6d
 | inotify wd:2 ino:a111 sdev:800013 mask:800afce ignored_mask:0 fhandle-bytes:8 fhandle-type:1 f_handle:11a1000020542153
 | inotify wd:1 ino:6b149 sdev:800013 mask:800afce ignored_mask:0 fhandle-bytes:8 fhandle-type:1 f_handle:49b1060023552153

If kernel compiled without exportfs support, the file handle
won't be provided but inode and device only.

 | pos:	0
 | flags:	02000000
 | inotify wd:3 ino:9e7e sdev:800013 mask:800afce ignored_mask:0
 | inotify wd:2 ino:a111 sdev:800013 mask:800afce ignored_mask:0
 | inotify wd:1 ino:6b149 sdev:800013 mask:800afce ignored_mask:0

For fanotify the output is like

 | pos:	0
 | flags:	04002
 | fanotify flags:10 event-flags:0
 | fanotify mnt_id:12 mask:3b ignored_mask:0
 | fanotify ino:50205 sdev:800013 mask:3b ignored_mask:40000000 fhandle-bytes:8 fhandle-type:1 f_handle:05020500fb1d47e7

To minimize impact on general fsnotify code the new functionality
is gathered in fs/notify/fdinfo.c file.
Signed-off-by: default avatarCyrill Gorcunov <gorcunov@openvz.org>
Acked-by: default avatarPavel Emelyanov <xemul@parallels.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: James Bottomley <jbottomley@parallels.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matthew Helsley <matt.helsley@gmail.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@onelan.co.uk>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 711c7bf9
obj-$(CONFIG_FSNOTIFY) += fsnotify.o notification.o group.o inode_mark.o \
mark.o vfsmount_mark.o
mark.o vfsmount_mark.o fdinfo.o
obj-y += dnotify/
obj-y += inotify/
......
......@@ -17,6 +17,7 @@
#include <asm/ioctls.h>
#include "../../mount.h"
#include "../fdinfo.h"
#define FANOTIFY_DEFAULT_MAX_EVENTS 16384
#define FANOTIFY_DEFAULT_MAX_MARKS 8192
......@@ -428,6 +429,7 @@ static long fanotify_ioctl(struct file *file, unsigned int cmd, unsigned long ar
}
static const struct file_operations fanotify_fops = {
.show_fdinfo = fanotify_show_fdinfo,
.poll = fanotify_poll,
.read = fanotify_read,
.write = fanotify_write,
......
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/fsnotify_backend.h>
#include <linux/idr.h>
#include <linux/init.h>
#include <linux/inotify.h>
#include <linux/fanotify.h>
#include <linux/kernel.h>
#include <linux/namei.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/seq_file.h>
#include <linux/proc_fs.h>
#include <linux/exportfs.h>
#include "inotify/inotify.h"
#include "../fs/mount.h"
#if defined(CONFIG_PROC_FS)
#if defined(CONFIG_INOTIFY_USER) || defined(CONFIG_FANOTIFY)
static int show_fdinfo(struct seq_file *m, struct file *f,
int (*show)(struct seq_file *m, struct fsnotify_mark *mark))
{
struct fsnotify_group *group = f->private_data;
struct fsnotify_mark *mark;
int ret = 0;
spin_lock(&group->mark_lock);
list_for_each_entry(mark, &group->marks_list, g_list) {
ret = show(m, mark);
if (ret)
break;
}
spin_unlock(&group->mark_lock);
return ret;
}
#if defined(CONFIG_EXPORTFS)
static int show_mark_fhandle(struct seq_file *m, struct inode *inode)
{
struct {
struct file_handle handle;
u8 pad[64];
} f;
int size, ret, i;
f.handle.handle_bytes = sizeof(f.pad);
size = f.handle.handle_bytes >> 2;
ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, 0);
if ((ret == 255) || (ret == -ENOSPC)) {
WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret);
return 0;
}
f.handle.handle_type = ret;
f.handle.handle_bytes = size * sizeof(u32);
ret = seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
f.handle.handle_bytes, f.handle.handle_type);
for (i = 0; i < f.handle.handle_bytes; i++)
ret |= seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
return ret;
}
#else
static int show_mark_fhandle(struct seq_file *m, struct inode *inode)
{
return 0;
}
#endif
#ifdef CONFIG_INOTIFY_USER
static int inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
{
struct inotify_inode_mark *inode_mark;
struct inode *inode;
int ret = 0;
if (!(mark->flags & (FSNOTIFY_MARK_FLAG_ALIVE | FSNOTIFY_MARK_FLAG_INODE)))
return 0;
inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark);
inode = igrab(mark->i.inode);
if (inode) {
ret = seq_printf(m, "inotify wd:%x ino:%lx sdev:%x "
"mask:%x ignored_mask:%x ",
inode_mark->wd, inode->i_ino,
inode->i_sb->s_dev,
mark->mask, mark->ignored_mask);
ret |= show_mark_fhandle(m, inode);
ret |= seq_putc(m, '\n');
iput(inode);
}
return ret;
}
int inotify_show_fdinfo(struct seq_file *m, struct file *f)
{
return show_fdinfo(m, f, inotify_fdinfo);
}
#endif /* CONFIG_INOTIFY_USER */
#ifdef CONFIG_FANOTIFY
static int fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
{
struct inode *inode;
int ret = 0;
if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE))
return 0;
if (mark->flags & FSNOTIFY_MARK_FLAG_INODE) {
inode = igrab(mark->i.inode);
if (!inode)
goto out;
ret = seq_printf(m, "fanotify ino:%lx sdev:%x "
"mask:%x ignored_mask:%x ",
inode->i_ino, inode->i_sb->s_dev,
mark->mask, mark->ignored_mask);
ret |= show_mark_fhandle(m, inode);
ret |= seq_putc(m, '\n');
iput(inode);
} else if (mark->flags & FSNOTIFY_MARK_FLAG_VFSMOUNT) {
struct mount *mnt = real_mount(mark->m.mnt);
ret = seq_printf(m, "fanotify mnt_id:%x mask:%x "
"ignored_mask:%x\n",
mnt->mnt_id, mark->mask, mark->ignored_mask);
}
out:
return ret;
}
int fanotify_show_fdinfo(struct seq_file *m, struct file *f)
{
struct fsnotify_group *group = f->private_data;
unsigned int flags = 0;
switch (group->priority) {
case FS_PRIO_0:
flags |= FAN_CLASS_NOTIF;
break;
case FS_PRIO_1:
flags |= FAN_CLASS_CONTENT;
break;
case FS_PRIO_2:
flags |= FAN_CLASS_PRE_CONTENT;
break;
}
if (group->max_events == UINT_MAX)
flags |= FAN_UNLIMITED_QUEUE;
if (group->fanotify_data.max_marks == UINT_MAX)
flags |= FAN_UNLIMITED_MARKS;
seq_printf(m, "fanotify flags:%x event-flags:%x\n",
flags, group->fanotify_data.f_flags);
return show_fdinfo(m, f, fanotify_fdinfo);
}
#endif /* CONFIG_FANOTIFY */
#endif /* CONFIG_INOTIFY_USER || CONFIG_FANOTIFY */
#endif /* CONFIG_PROC_FS */
#ifndef __FSNOTIFY_FDINFO_H__
#define __FSNOTIFY_FDINFO_H__
#include <linux/errno.h>
#include <linux/proc_fs.h>
struct seq_file;
struct file;
#ifdef CONFIG_PROC_FS
#ifdef CONFIG_INOTIFY_USER
extern int inotify_show_fdinfo(struct seq_file *m, struct file *f);
#endif
#ifdef CONFIG_FANOTIFY
extern int fanotify_show_fdinfo(struct seq_file *m, struct file *f);
#endif
#else /* CONFIG_PROC_FS */
#define inotify_show_fdinfo NULL
#define fanotify_show_fdinfo NULL
#endif /* CONFIG_PROC_FS */
#endif /* __FSNOTIFY_FDINFO_H__ */
......@@ -40,6 +40,7 @@
#include <linux/wait.h>
#include "inotify.h"
#include "../fdinfo.h"
#include <asm/ioctls.h>
......@@ -335,6 +336,7 @@ static long inotify_ioctl(struct file *file, unsigned int cmd,
}
static const struct file_operations inotify_fops = {
.show_fdinfo = inotify_show_fdinfo,
.poll = inotify_poll,
.read = inotify_read,
.fasync = inotify_fasync,
......
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