Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 1 | /* |
| 2 | * fs/inotify_user.c - inotify support for userspace |
| 3 | * |
| 4 | * Authors: |
| 5 | * John McCutchan <ttb@tentacle.dhs.org> |
| 6 | * Robert Love <rml@novell.com> |
| 7 | * |
| 8 | * Copyright (C) 2005 John McCutchan |
| 9 | * Copyright 2006 Hewlett-Packard Development Company, L.P. |
| 10 | * |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 11 | * Copyright (C) 2009 Eric Paris <Red Hat Inc> |
| 12 | * inotify was largely rewriten to make use of the fsnotify infrastructure |
| 13 | * |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 14 | * This program is free software; you can redistribute it and/or modify it |
| 15 | * under the terms of the GNU General Public License as published by the |
| 16 | * Free Software Foundation; either version 2, or (at your option) any |
| 17 | * later version. |
| 18 | * |
| 19 | * This program is distributed in the hope that it will be useful, but |
| 20 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 22 | * General Public License for more details. |
| 23 | */ |
| 24 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 25 | #include <linux/file.h> |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 26 | #include <linux/fs.h> /* struct inode */ |
| 27 | #include <linux/fsnotify_backend.h> |
| 28 | #include <linux/idr.h> |
| 29 | #include <linux/init.h> /* module_init */ |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 30 | #include <linux/inotify.h> |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 31 | #include <linux/kernel.h> /* roundup() */ |
| 32 | #include <linux/magic.h> /* superblock magic number */ |
| 33 | #include <linux/mount.h> /* mntget */ |
| 34 | #include <linux/namei.h> /* LOOKUP_FOLLOW */ |
| 35 | #include <linux/path.h> /* struct path */ |
| 36 | #include <linux/sched.h> /* struct user */ |
| 37 | #include <linux/slab.h> /* struct kmem_cache */ |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 38 | #include <linux/syscalls.h> |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 39 | #include <linux/types.h> |
| 40 | #include <linux/uaccess.h> |
| 41 | #include <linux/poll.h> |
| 42 | #include <linux/wait.h> |
| 43 | |
| 44 | #include "inotify.h" |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 45 | |
| 46 | #include <asm/ioctls.h> |
| 47 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 48 | static struct vfsmount *inotify_mnt __read_mostly; |
| 49 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 50 | /* this just sits here and wastes global memory. used to just pad userspace messages with zeros */ |
| 51 | static struct inotify_event nul_inotify_event; |
| 52 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 53 | /* these are configurable via /proc/sys/fs/inotify/ */ |
Harvey Harrison | 3c828e4 | 2008-02-14 19:31:21 -0800 | [diff] [blame] | 54 | static int inotify_max_user_instances __read_mostly; |
Harvey Harrison | 3c828e4 | 2008-02-14 19:31:21 -0800 | [diff] [blame] | 55 | static int inotify_max_queued_events __read_mostly; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 56 | int inotify_max_user_watches __read_mostly; |
| 57 | |
| 58 | static struct kmem_cache *inotify_inode_mark_cachep __read_mostly; |
| 59 | struct kmem_cache *event_priv_cachep __read_mostly; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 60 | |
| 61 | /* |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 62 | * When inotify registers a new group it increments this and uses that |
| 63 | * value as an offset to set the fsnotify group "name" and priority. |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 64 | */ |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 65 | static atomic_t inotify_grp_num; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 66 | |
| 67 | #ifdef CONFIG_SYSCTL |
| 68 | |
| 69 | #include <linux/sysctl.h> |
| 70 | |
| 71 | static int zero; |
| 72 | |
| 73 | ctl_table inotify_table[] = { |
| 74 | { |
| 75 | .ctl_name = INOTIFY_MAX_USER_INSTANCES, |
| 76 | .procname = "max_user_instances", |
| 77 | .data = &inotify_max_user_instances, |
| 78 | .maxlen = sizeof(int), |
| 79 | .mode = 0644, |
| 80 | .proc_handler = &proc_dointvec_minmax, |
| 81 | .strategy = &sysctl_intvec, |
| 82 | .extra1 = &zero, |
| 83 | }, |
| 84 | { |
| 85 | .ctl_name = INOTIFY_MAX_USER_WATCHES, |
| 86 | .procname = "max_user_watches", |
| 87 | .data = &inotify_max_user_watches, |
| 88 | .maxlen = sizeof(int), |
| 89 | .mode = 0644, |
| 90 | .proc_handler = &proc_dointvec_minmax, |
| 91 | .strategy = &sysctl_intvec, |
| 92 | .extra1 = &zero, |
| 93 | }, |
| 94 | { |
| 95 | .ctl_name = INOTIFY_MAX_QUEUED_EVENTS, |
| 96 | .procname = "max_queued_events", |
| 97 | .data = &inotify_max_queued_events, |
| 98 | .maxlen = sizeof(int), |
| 99 | .mode = 0644, |
| 100 | .proc_handler = &proc_dointvec_minmax, |
| 101 | .strategy = &sysctl_intvec, |
| 102 | .extra1 = &zero |
| 103 | }, |
| 104 | { .ctl_name = 0 } |
| 105 | }; |
| 106 | #endif /* CONFIG_SYSCTL */ |
| 107 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 108 | static inline __u32 inotify_arg_to_mask(u32 arg) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 109 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 110 | __u32 mask; |
| 111 | |
| 112 | /* everything should accept their own ignored and cares about children */ |
| 113 | mask = (FS_IN_IGNORED | FS_EVENT_ON_CHILD); |
| 114 | |
| 115 | /* mask off the flags used to open the fd */ |
| 116 | mask |= (arg & (IN_ALL_EVENTS | IN_ONESHOT)); |
| 117 | |
| 118 | return mask; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 119 | } |
| 120 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 121 | static inline u32 inotify_mask_to_arg(__u32 mask) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 122 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 123 | return mask & (IN_ALL_EVENTS | IN_ISDIR | IN_UNMOUNT | IN_IGNORED | |
| 124 | IN_Q_OVERFLOW); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 125 | } |
| 126 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 127 | /* intofiy userspace file descriptor functions */ |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 128 | static unsigned int inotify_poll(struct file *file, poll_table *wait) |
| 129 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 130 | struct fsnotify_group *group = file->private_data; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 131 | int ret = 0; |
| 132 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 133 | poll_wait(file, &group->notification_waitq, wait); |
| 134 | mutex_lock(&group->notification_mutex); |
| 135 | if (!fsnotify_notify_queue_is_empty(group)) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 136 | ret = POLLIN | POLLRDNORM; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 137 | mutex_unlock(&group->notification_mutex); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 138 | |
| 139 | return ret; |
| 140 | } |
| 141 | |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 142 | /* |
| 143 | * Get an inotify_kernel_event if one exists and is small |
| 144 | * enough to fit in "count". Return an error pointer if |
| 145 | * not large enough. |
| 146 | * |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 147 | * Called with the group->notification_mutex held. |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 148 | */ |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 149 | static struct fsnotify_event *get_one_event(struct fsnotify_group *group, |
| 150 | size_t count) |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 151 | { |
| 152 | size_t event_size = sizeof(struct inotify_event); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 153 | struct fsnotify_event *event; |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 154 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 155 | if (fsnotify_notify_queue_is_empty(group)) |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 156 | return NULL; |
| 157 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 158 | event = fsnotify_peek_notify_event(group); |
| 159 | |
| 160 | event_size += roundup(event->name_len, event_size); |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 161 | |
| 162 | if (event_size > count) |
| 163 | return ERR_PTR(-EINVAL); |
| 164 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 165 | /* held the notification_mutex the whole time, so this is the |
| 166 | * same event we peeked above */ |
| 167 | fsnotify_remove_notify_event(group); |
| 168 | |
| 169 | return event; |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 170 | } |
| 171 | |
| 172 | /* |
| 173 | * Copy an event to user space, returning how much we copied. |
| 174 | * |
| 175 | * We already checked that the event size is smaller than the |
| 176 | * buffer we had in "get_one_event()" above. |
| 177 | */ |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 178 | static ssize_t copy_event_to_user(struct fsnotify_group *group, |
| 179 | struct fsnotify_event *event, |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 180 | char __user *buf) |
| 181 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 182 | struct inotify_event inotify_event; |
| 183 | struct fsnotify_event_private_data *fsn_priv; |
| 184 | struct inotify_event_private_data *priv; |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 185 | size_t event_size = sizeof(struct inotify_event); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 186 | size_t name_len; |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 187 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 188 | /* we get the inotify watch descriptor from the event private data */ |
| 189 | spin_lock(&event->lock); |
| 190 | fsn_priv = fsnotify_remove_priv_from_event(group, event); |
| 191 | spin_unlock(&event->lock); |
| 192 | |
| 193 | if (!fsn_priv) |
| 194 | inotify_event.wd = -1; |
| 195 | else { |
| 196 | priv = container_of(fsn_priv, struct inotify_event_private_data, |
| 197 | fsnotify_event_priv_data); |
| 198 | inotify_event.wd = priv->wd; |
| 199 | inotify_free_event_priv(fsn_priv); |
| 200 | } |
| 201 | |
| 202 | /* round up event->name_len so it is a multiple of event_size */ |
| 203 | name_len = roundup(event->name_len, event_size); |
| 204 | inotify_event.len = name_len; |
| 205 | |
| 206 | inotify_event.mask = inotify_mask_to_arg(event->mask); |
| 207 | inotify_event.cookie = event->sync_cookie; |
| 208 | |
| 209 | /* send the main event */ |
| 210 | if (copy_to_user(buf, &inotify_event, event_size)) |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 211 | return -EFAULT; |
| 212 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 213 | buf += event_size; |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 214 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 215 | /* |
| 216 | * fsnotify only stores the pathname, so here we have to send the pathname |
| 217 | * and then pad that pathname out to a multiple of sizeof(inotify_event) |
| 218 | * with zeros. I get my zeros from the nul_inotify_event. |
| 219 | */ |
| 220 | if (name_len) { |
| 221 | unsigned int len_to_zero = name_len - event->name_len; |
| 222 | /* copy the path name */ |
| 223 | if (copy_to_user(buf, event->file_name, event->name_len)) |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 224 | return -EFAULT; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 225 | buf += event->name_len; |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 226 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 227 | /* fill userspace with 0's from nul_inotify_event */ |
| 228 | if (copy_to_user(buf, &nul_inotify_event, len_to_zero)) |
| 229 | return -EFAULT; |
| 230 | buf += len_to_zero; |
| 231 | event_size += name_len; |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 232 | } |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 233 | |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 234 | return event_size; |
| 235 | } |
| 236 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 237 | static ssize_t inotify_read(struct file *file, char __user *buf, |
| 238 | size_t count, loff_t *pos) |
| 239 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 240 | struct fsnotify_group *group; |
| 241 | struct fsnotify_event *kevent; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 242 | char __user *start; |
| 243 | int ret; |
| 244 | DEFINE_WAIT(wait); |
| 245 | |
| 246 | start = buf; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 247 | group = file->private_data; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 248 | |
| 249 | while (1) { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 250 | prepare_to_wait(&group->notification_waitq, &wait, TASK_INTERRUPTIBLE); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 251 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 252 | mutex_lock(&group->notification_mutex); |
| 253 | kevent = get_one_event(group, count); |
| 254 | mutex_unlock(&group->notification_mutex); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 255 | |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 256 | if (kevent) { |
| 257 | ret = PTR_ERR(kevent); |
| 258 | if (IS_ERR(kevent)) |
| 259 | break; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 260 | ret = copy_event_to_user(group, kevent, buf); |
| 261 | fsnotify_put_event(kevent); |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 262 | if (ret < 0) |
| 263 | break; |
| 264 | buf += ret; |
| 265 | count -= ret; |
| 266 | continue; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 267 | } |
| 268 | |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 269 | ret = -EAGAIN; |
| 270 | if (file->f_flags & O_NONBLOCK) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 271 | break; |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 272 | ret = -EINTR; |
| 273 | if (signal_pending(current)) |
| 274 | break; |
| 275 | |
| 276 | if (start != buf) |
| 277 | break; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 278 | |
| 279 | schedule(); |
| 280 | } |
| 281 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 282 | finish_wait(&group->notification_waitq, &wait); |
Vegard Nossum | 3632dee | 2009-01-22 15:29:45 +0100 | [diff] [blame] | 283 | if (start != buf && ret != -EFAULT) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 284 | ret = buf - start; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 285 | return ret; |
| 286 | } |
| 287 | |
Dmitry Antipov | bcfbf84 | 2008-02-06 01:36:19 -0800 | [diff] [blame] | 288 | static int inotify_fasync(int fd, struct file *file, int on) |
| 289 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 290 | struct fsnotify_group *group = file->private_data; |
Dmitry Antipov | bcfbf84 | 2008-02-06 01:36:19 -0800 | [diff] [blame] | 291 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 292 | return fasync_helper(fd, file, on, &group->inotify_data.fa) >= 0 ? 0 : -EIO; |
Dmitry Antipov | bcfbf84 | 2008-02-06 01:36:19 -0800 | [diff] [blame] | 293 | } |
| 294 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 295 | static int inotify_release(struct inode *ignored, struct file *file) |
| 296 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 297 | struct fsnotify_group *group = file->private_data; |
Keith Packard | bdae997 | 2009-07-01 21:56:38 -0700 | [diff] [blame] | 298 | struct user_struct *user = group->inotify_data.user; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 299 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 300 | fsnotify_clear_marks_by_group(group); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 301 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 302 | /* free this group, matching get was inotify_init->fsnotify_obtain_group */ |
| 303 | fsnotify_put_group(group); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 304 | |
Keith Packard | bdae997 | 2009-07-01 21:56:38 -0700 | [diff] [blame] | 305 | atomic_dec(&user->inotify_devs); |
| 306 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 307 | return 0; |
| 308 | } |
| 309 | |
| 310 | static long inotify_ioctl(struct file *file, unsigned int cmd, |
| 311 | unsigned long arg) |
| 312 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 313 | struct fsnotify_group *group; |
| 314 | struct fsnotify_event_holder *holder; |
| 315 | struct fsnotify_event *event; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 316 | void __user *p; |
| 317 | int ret = -ENOTTY; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 318 | size_t send_len = 0; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 319 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 320 | group = file->private_data; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 321 | p = (void __user *) arg; |
| 322 | |
| 323 | switch (cmd) { |
| 324 | case FIONREAD: |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 325 | mutex_lock(&group->notification_mutex); |
| 326 | list_for_each_entry(holder, &group->notification_list, event_list) { |
| 327 | event = holder->event; |
| 328 | send_len += sizeof(struct inotify_event); |
| 329 | send_len += roundup(event->name_len, |
| 330 | sizeof(struct inotify_event)); |
| 331 | } |
| 332 | mutex_unlock(&group->notification_mutex); |
| 333 | ret = put_user(send_len, (int __user *) p); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 334 | break; |
| 335 | } |
| 336 | |
| 337 | return ret; |
| 338 | } |
| 339 | |
| 340 | static const struct file_operations inotify_fops = { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 341 | .poll = inotify_poll, |
| 342 | .read = inotify_read, |
| 343 | .fasync = inotify_fasync, |
| 344 | .release = inotify_release, |
| 345 | .unlocked_ioctl = inotify_ioctl, |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 346 | .compat_ioctl = inotify_ioctl, |
| 347 | }; |
| 348 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 349 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 350 | /* |
| 351 | * find_inode - resolve a user-given path to a specific inode |
| 352 | */ |
| 353 | static int inotify_find_inode(const char __user *dirname, struct path *path, unsigned flags) |
| 354 | { |
| 355 | int error; |
| 356 | |
| 357 | error = user_path_at(AT_FDCWD, dirname, flags, path); |
| 358 | if (error) |
| 359 | return error; |
| 360 | /* you can only watch an inode if you have read permissions on it */ |
| 361 | error = inode_permission(path->dentry->d_inode, MAY_READ); |
| 362 | if (error) |
| 363 | path_put(path); |
| 364 | return error; |
| 365 | } |
| 366 | |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 367 | static void inotify_remove_from_idr(struct fsnotify_group *group, |
| 368 | struct inotify_inode_mark_entry *ientry) |
| 369 | { |
| 370 | struct idr *idr; |
| 371 | |
| 372 | spin_lock(&group->inotify_data.idr_lock); |
| 373 | idr = &group->inotify_data.idr; |
| 374 | idr_remove(idr, ientry->wd); |
| 375 | spin_unlock(&group->inotify_data.idr_lock); |
| 376 | ientry->wd = -1; |
| 377 | } |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 378 | /* |
Eric Paris | 528da3e | 2009-06-12 16:04:26 -0400 | [diff] [blame] | 379 | * Send IN_IGNORED for this wd, remove this wd from the idr, and drop the |
| 380 | * internal reference help on the mark because it is in the idr. |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 381 | */ |
Eric Paris | 528da3e | 2009-06-12 16:04:26 -0400 | [diff] [blame] | 382 | void inotify_ignored_and_remove_idr(struct fsnotify_mark_entry *entry, |
| 383 | struct fsnotify_group *group) |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 384 | { |
| 385 | struct inotify_inode_mark_entry *ientry; |
Eric Paris | f44aebc | 2009-07-15 15:49:52 -0400 | [diff] [blame] | 386 | struct fsnotify_event *ignored_event; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 387 | struct inotify_event_private_data *event_priv; |
| 388 | struct fsnotify_event_private_data *fsn_event_priv; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 389 | |
Eric Paris | f44aebc | 2009-07-15 15:49:52 -0400 | [diff] [blame] | 390 | ignored_event = fsnotify_create_event(NULL, FS_IN_IGNORED, NULL, |
| 391 | FSNOTIFY_EVENT_NONE, NULL, 0, |
| 392 | GFP_NOFS); |
| 393 | if (!ignored_event) |
| 394 | return; |
| 395 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 396 | ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); |
| 397 | |
Eric Paris | f44aebc | 2009-07-15 15:49:52 -0400 | [diff] [blame] | 398 | event_priv = kmem_cache_alloc(event_priv_cachep, GFP_NOFS); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 399 | if (unlikely(!event_priv)) |
| 400 | goto skip_send_ignore; |
| 401 | |
| 402 | fsn_event_priv = &event_priv->fsnotify_event_priv_data; |
| 403 | |
| 404 | fsn_event_priv->group = group; |
| 405 | event_priv->wd = ientry->wd; |
| 406 | |
Eric Paris | f44aebc | 2009-07-15 15:49:52 -0400 | [diff] [blame] | 407 | fsnotify_add_notify_event(group, ignored_event, fsn_event_priv); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 408 | |
| 409 | /* did the private data get added? */ |
| 410 | if (list_empty(&fsn_event_priv->event_list)) |
| 411 | inotify_free_event_priv(fsn_event_priv); |
| 412 | |
| 413 | skip_send_ignore: |
| 414 | |
Eric Paris | f44aebc | 2009-07-15 15:49:52 -0400 | [diff] [blame] | 415 | /* matches the reference taken when the event was created */ |
| 416 | fsnotify_put_event(ignored_event); |
| 417 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 418 | /* remove this entry from the idr */ |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 419 | inotify_remove_from_idr(group, ientry); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 420 | |
| 421 | /* removed from idr, drop that reference */ |
| 422 | fsnotify_put_mark(entry); |
Eric Paris | 5549f7c | 2009-07-07 10:28:23 -0400 | [diff] [blame] | 423 | |
| 424 | atomic_dec(&group->inotify_data.user->inotify_watches); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 425 | } |
| 426 | |
| 427 | /* ding dong the mark is dead */ |
| 428 | static void inotify_free_mark(struct fsnotify_mark_entry *entry) |
| 429 | { |
| 430 | struct inotify_inode_mark_entry *ientry = (struct inotify_inode_mark_entry *)entry; |
| 431 | |
| 432 | kmem_cache_free(inotify_inode_mark_cachep, ientry); |
| 433 | } |
| 434 | |
| 435 | static int inotify_update_watch(struct fsnotify_group *group, struct inode *inode, u32 arg) |
| 436 | { |
| 437 | struct fsnotify_mark_entry *entry = NULL; |
| 438 | struct inotify_inode_mark_entry *ientry; |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 439 | struct inotify_inode_mark_entry *tmp_ientry; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 440 | int ret = 0; |
| 441 | int add = (arg & IN_MASK_ADD); |
| 442 | __u32 mask; |
| 443 | __u32 old_mask, new_mask; |
| 444 | |
| 445 | /* don't allow invalid bits: we don't want flags set */ |
| 446 | mask = inotify_arg_to_mask(arg); |
| 447 | if (unlikely(!mask)) |
| 448 | return -EINVAL; |
| 449 | |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 450 | tmp_ientry = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL); |
| 451 | if (unlikely(!tmp_ientry)) |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 452 | return -ENOMEM; |
| 453 | /* we set the mask at the end after attaching it */ |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 454 | fsnotify_init_mark(&tmp_ientry->fsn_entry, inotify_free_mark); |
| 455 | tmp_ientry->wd = -1; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 456 | |
| 457 | find_entry: |
| 458 | spin_lock(&inode->i_lock); |
| 459 | entry = fsnotify_find_mark_entry(group, inode); |
| 460 | spin_unlock(&inode->i_lock); |
| 461 | if (entry) { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 462 | ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); |
| 463 | } else { |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 464 | ret = -ENOSPC; |
| 465 | if (atomic_read(&group->inotify_data.user->inotify_watches) >= inotify_max_user_watches) |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 466 | goto out_err; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 467 | retry: |
| 468 | ret = -ENOMEM; |
| 469 | if (unlikely(!idr_pre_get(&group->inotify_data.idr, GFP_KERNEL))) |
| 470 | goto out_err; |
| 471 | |
| 472 | spin_lock(&group->inotify_data.idr_lock); |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 473 | ret = idr_get_new_above(&group->inotify_data.idr, &tmp_ientry->fsn_entry, |
| 474 | group->inotify_data.last_wd, |
| 475 | &tmp_ientry->wd); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 476 | spin_unlock(&group->inotify_data.idr_lock); |
| 477 | if (ret) { |
| 478 | if (ret == -EAGAIN) |
| 479 | goto retry; |
| 480 | goto out_err; |
| 481 | } |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 482 | |
| 483 | ret = fsnotify_add_mark(&tmp_ientry->fsn_entry, group, inode); |
| 484 | if (ret) { |
| 485 | inotify_remove_from_idr(group, tmp_ientry); |
| 486 | if (ret == -EEXIST) |
| 487 | goto find_entry; |
| 488 | goto out_err; |
| 489 | } |
| 490 | |
| 491 | /* tmp_ientry has been added to the inode, so we are all set up. |
| 492 | * now we just need to make sure tmp_ientry doesn't get freed and |
| 493 | * we need to set up entry and ientry so the generic code can |
| 494 | * do its thing. */ |
| 495 | ientry = tmp_ientry; |
| 496 | entry = &ientry->fsn_entry; |
| 497 | tmp_ientry = NULL; |
| 498 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 499 | atomic_inc(&group->inotify_data.user->inotify_watches); |
Eric Paris | 75fe2b2 | 2009-07-07 10:28:23 -0400 | [diff] [blame] | 500 | |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 501 | /* update the idr hint */ |
| 502 | group->inotify_data.last_wd = ientry->wd; |
| 503 | |
Eric Paris | 75fe2b2 | 2009-07-07 10:28:23 -0400 | [diff] [blame] | 504 | /* we put the mark on the idr, take a reference */ |
| 505 | fsnotify_get_mark(entry); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 506 | } |
| 507 | |
Eric Paris | 75fe2b2 | 2009-07-07 10:28:23 -0400 | [diff] [blame] | 508 | ret = ientry->wd; |
| 509 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 510 | spin_lock(&entry->lock); |
| 511 | |
| 512 | old_mask = entry->mask; |
| 513 | if (add) { |
| 514 | entry->mask |= mask; |
| 515 | new_mask = entry->mask; |
| 516 | } else { |
| 517 | entry->mask = mask; |
| 518 | new_mask = entry->mask; |
| 519 | } |
| 520 | |
| 521 | spin_unlock(&entry->lock); |
| 522 | |
| 523 | if (old_mask != new_mask) { |
| 524 | /* more bits in old than in new? */ |
| 525 | int dropped = (old_mask & ~new_mask); |
| 526 | /* more bits in this entry than the inode's mask? */ |
| 527 | int do_inode = (new_mask & ~inode->i_fsnotify_mask); |
| 528 | /* more bits in this entry than the group? */ |
| 529 | int do_group = (new_mask & ~group->mask); |
| 530 | |
| 531 | /* update the inode with this new entry */ |
| 532 | if (dropped || do_inode) |
| 533 | fsnotify_recalc_inode_mask(inode); |
| 534 | |
| 535 | /* update the group mask with the new mask */ |
| 536 | if (dropped || do_group) |
| 537 | fsnotify_recalc_group_mask(group); |
| 538 | } |
| 539 | |
Eric Paris | 75fe2b2 | 2009-07-07 10:28:23 -0400 | [diff] [blame] | 540 | /* this either matches fsnotify_find_mark_entry, or init_mark_entry |
| 541 | * depending on which path we took... */ |
| 542 | fsnotify_put_mark(entry); |
| 543 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 544 | out_err: |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 545 | /* could be an error, could be that we found an existing mark */ |
| 546 | if (tmp_ientry) { |
| 547 | /* on the idr but didn't make it on the inode */ |
| 548 | if (tmp_ientry->wd != -1) |
| 549 | inotify_remove_from_idr(group, tmp_ientry); |
| 550 | kmem_cache_free(inotify_inode_mark_cachep, tmp_ientry); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 551 | } |
Eric Paris | 7e790dd | 2009-07-07 10:28:24 -0400 | [diff] [blame] | 552 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 553 | return ret; |
| 554 | } |
| 555 | |
| 556 | static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsigned int max_events) |
| 557 | { |
| 558 | struct fsnotify_group *group; |
| 559 | unsigned int grp_num; |
| 560 | |
| 561 | /* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */ |
| 562 | grp_num = (INOTIFY_GROUP_NUM - atomic_inc_return(&inotify_grp_num)); |
| 563 | group = fsnotify_obtain_group(grp_num, 0, &inotify_fsnotify_ops); |
| 564 | if (IS_ERR(group)) |
| 565 | return group; |
| 566 | |
| 567 | group->max_events = max_events; |
| 568 | |
| 569 | spin_lock_init(&group->inotify_data.idr_lock); |
| 570 | idr_init(&group->inotify_data.idr); |
| 571 | group->inotify_data.last_wd = 0; |
| 572 | group->inotify_data.user = user; |
| 573 | group->inotify_data.fa = NULL; |
| 574 | |
| 575 | return group; |
| 576 | } |
| 577 | |
| 578 | |
| 579 | /* inotify syscalls */ |
Heiko Carstens | 938bb9f | 2009-01-14 14:14:30 +0100 | [diff] [blame] | 580 | SYSCALL_DEFINE1(inotify_init1, int, flags) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 581 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 582 | struct fsnotify_group *group; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 583 | struct user_struct *user; |
| 584 | struct file *filp; |
| 585 | int fd, ret; |
| 586 | |
Ulrich Drepper | e38b36f | 2008-07-23 21:29:42 -0700 | [diff] [blame] | 587 | /* Check the IN_* constants for consistency. */ |
| 588 | BUILD_BUG_ON(IN_CLOEXEC != O_CLOEXEC); |
| 589 | BUILD_BUG_ON(IN_NONBLOCK != O_NONBLOCK); |
| 590 | |
Ulrich Drepper | 510df2d | 2008-07-23 21:29:41 -0700 | [diff] [blame] | 591 | if (flags & ~(IN_CLOEXEC | IN_NONBLOCK)) |
Ulrich Drepper | 4006553 | 2008-07-23 21:29:32 -0700 | [diff] [blame] | 592 | return -EINVAL; |
| 593 | |
| 594 | fd = get_unused_fd_flags(flags & O_CLOEXEC); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 595 | if (fd < 0) |
| 596 | return fd; |
| 597 | |
| 598 | filp = get_empty_filp(); |
| 599 | if (!filp) { |
| 600 | ret = -ENFILE; |
| 601 | goto out_put_fd; |
| 602 | } |
| 603 | |
David Howells | da9592e | 2008-11-14 10:39:05 +1100 | [diff] [blame] | 604 | user = get_current_user(); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 605 | if (unlikely(atomic_read(&user->inotify_devs) >= |
| 606 | inotify_max_user_instances)) { |
| 607 | ret = -EMFILE; |
| 608 | goto out_free_uid; |
| 609 | } |
| 610 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 611 | /* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */ |
| 612 | group = inotify_new_group(user, inotify_max_queued_events); |
| 613 | if (IS_ERR(group)) { |
| 614 | ret = PTR_ERR(group); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 615 | goto out_free_uid; |
| 616 | } |
| 617 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 618 | filp->f_op = &inotify_fops; |
Josef "Jeff" Sipek | 0f7fc9e | 2006-12-08 02:36:35 -0800 | [diff] [blame] | 619 | filp->f_path.mnt = mntget(inotify_mnt); |
| 620 | filp->f_path.dentry = dget(inotify_mnt->mnt_root); |
| 621 | filp->f_mapping = filp->f_path.dentry->d_inode->i_mapping; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 622 | filp->f_mode = FMODE_READ; |
Ulrich Drepper | 510df2d | 2008-07-23 21:29:41 -0700 | [diff] [blame] | 623 | filp->f_flags = O_RDONLY | (flags & O_NONBLOCK); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 624 | filp->private_data = group; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 625 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 626 | atomic_inc(&user->inotify_devs); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 627 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 628 | fd_install(fd, filp); |
| 629 | |
| 630 | return fd; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 631 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 632 | out_free_uid: |
| 633 | free_uid(user); |
| 634 | put_filp(filp); |
| 635 | out_put_fd: |
| 636 | put_unused_fd(fd); |
| 637 | return ret; |
| 638 | } |
| 639 | |
Heiko Carstens | 938bb9f | 2009-01-14 14:14:30 +0100 | [diff] [blame] | 640 | SYSCALL_DEFINE0(inotify_init) |
Ulrich Drepper | 4006553 | 2008-07-23 21:29:32 -0700 | [diff] [blame] | 641 | { |
| 642 | return sys_inotify_init1(0); |
| 643 | } |
| 644 | |
Heiko Carstens | 2e4d092 | 2009-01-14 14:14:31 +0100 | [diff] [blame] | 645 | SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname, |
| 646 | u32, mask) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 647 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 648 | struct fsnotify_group *group; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 649 | struct inode *inode; |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 650 | struct path path; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 651 | struct file *filp; |
| 652 | int ret, fput_needed; |
| 653 | unsigned flags = 0; |
| 654 | |
| 655 | filp = fget_light(fd, &fput_needed); |
| 656 | if (unlikely(!filp)) |
| 657 | return -EBADF; |
| 658 | |
| 659 | /* verify that this is indeed an inotify instance */ |
| 660 | if (unlikely(filp->f_op != &inotify_fops)) { |
| 661 | ret = -EINVAL; |
| 662 | goto fput_and_out; |
| 663 | } |
| 664 | |
| 665 | if (!(mask & IN_DONT_FOLLOW)) |
| 666 | flags |= LOOKUP_FOLLOW; |
| 667 | if (mask & IN_ONLYDIR) |
| 668 | flags |= LOOKUP_DIRECTORY; |
| 669 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 670 | ret = inotify_find_inode(pathname, &path, flags); |
| 671 | if (ret) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 672 | goto fput_and_out; |
| 673 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 674 | /* inode held in place by reference to path; group by fget on fd */ |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 675 | inode = path.dentry->d_inode; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 676 | group = filp->private_data; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 677 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 678 | /* create/update an inode mark */ |
| 679 | ret = inotify_update_watch(group, inode, mask); |
| 680 | if (unlikely(ret)) |
| 681 | goto path_put_and_out; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 682 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 683 | path_put_and_out: |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 684 | path_put(&path); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 685 | fput_and_out: |
| 686 | fput_light(filp, fput_needed); |
| 687 | return ret; |
| 688 | } |
| 689 | |
Heiko Carstens | 2e4d092 | 2009-01-14 14:14:31 +0100 | [diff] [blame] | 690 | SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 691 | { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 692 | struct fsnotify_group *group; |
| 693 | struct fsnotify_mark_entry *entry; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 694 | struct file *filp; |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 695 | int ret = 0, fput_needed; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 696 | |
| 697 | filp = fget_light(fd, &fput_needed); |
| 698 | if (unlikely(!filp)) |
| 699 | return -EBADF; |
| 700 | |
| 701 | /* verify that this is indeed an inotify instance */ |
| 702 | if (unlikely(filp->f_op != &inotify_fops)) { |
| 703 | ret = -EINVAL; |
| 704 | goto out; |
| 705 | } |
| 706 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 707 | group = filp->private_data; |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 708 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 709 | spin_lock(&group->inotify_data.idr_lock); |
| 710 | entry = idr_find(&group->inotify_data.idr, wd); |
| 711 | if (unlikely(!entry)) { |
| 712 | spin_unlock(&group->inotify_data.idr_lock); |
| 713 | ret = -EINVAL; |
| 714 | goto out; |
| 715 | } |
| 716 | fsnotify_get_mark(entry); |
| 717 | spin_unlock(&group->inotify_data.idr_lock); |
| 718 | |
Eric Paris | 528da3e | 2009-06-12 16:04:26 -0400 | [diff] [blame] | 719 | fsnotify_destroy_mark_by_entry(entry); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 720 | fsnotify_put_mark(entry); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 721 | |
| 722 | out: |
| 723 | fput_light(filp, fput_needed); |
| 724 | return ret; |
| 725 | } |
| 726 | |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 727 | static int |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 728 | inotify_get_sb(struct file_system_type *fs_type, int flags, |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 729 | const char *dev_name, void *data, struct vfsmount *mnt) |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 730 | { |
Andrey Mirkin | fd5eea4 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 731 | return get_sb_pseudo(fs_type, "inotify", NULL, |
| 732 | INOTIFYFS_SUPER_MAGIC, mnt); |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 733 | } |
| 734 | |
| 735 | static struct file_system_type inotify_fs_type = { |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 736 | .name = "inotifyfs", |
| 737 | .get_sb = inotify_get_sb, |
| 738 | .kill_sb = kill_anon_super, |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 739 | }; |
| 740 | |
| 741 | /* |
| 742 | * inotify_user_setup - Our initialization function. Note that we cannnot return |
| 743 | * error because we have compiled-in VFS hooks. So an (unlikely) failure here |
| 744 | * must result in panic(). |
| 745 | */ |
| 746 | static int __init inotify_user_setup(void) |
| 747 | { |
| 748 | int ret; |
| 749 | |
| 750 | ret = register_filesystem(&inotify_fs_type); |
| 751 | if (unlikely(ret)) |
| 752 | panic("inotify: register_filesystem returned %d!\n", ret); |
| 753 | |
| 754 | inotify_mnt = kern_mount(&inotify_fs_type); |
| 755 | if (IS_ERR(inotify_mnt)) |
| 756 | panic("inotify: kern_mount ret %ld!\n", PTR_ERR(inotify_mnt)); |
| 757 | |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 758 | inotify_inode_mark_cachep = KMEM_CACHE(inotify_inode_mark_entry, SLAB_PANIC); |
| 759 | event_priv_cachep = KMEM_CACHE(inotify_event_private_data, SLAB_PANIC); |
Eric Paris | 63c882a | 2009-05-21 17:02:01 -0400 | [diff] [blame] | 760 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 761 | inotify_max_queued_events = 16384; |
| 762 | inotify_max_user_instances = 128; |
| 763 | inotify_max_user_watches = 8192; |
| 764 | |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 765 | return 0; |
| 766 | } |
Amy Griffis | 2d9048e | 2006-06-01 13:10:59 -0700 | [diff] [blame] | 767 | module_init(inotify_user_setup); |