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-rw-r--r--fs/inotify.c116
1 files changed, 58 insertions, 58 deletions
diff --git a/fs/inotify.c b/fs/inotify.c
index 3041503bde02..0ee39ef591c6 100644
--- a/fs/inotify.c
+++ b/fs/inotify.c
@@ -54,10 +54,10 @@ int inotify_max_queued_events;
54 * Lock ordering: 54 * Lock ordering:
55 * 55 *
56 * dentry->d_lock (used to keep d_move() away from dentry->d_parent) 56 * dentry->d_lock (used to keep d_move() away from dentry->d_parent)
57 * iprune_sem (synchronize shrink_icache_memory()) 57 * iprune_mutex (synchronize shrink_icache_memory())
58 * inode_lock (protects the super_block->s_inodes list) 58 * inode_lock (protects the super_block->s_inodes list)
59 * inode->inotify_sem (protects inode->inotify_watches and watches->i_list) 59 * inode->inotify_mutex (protects inode->inotify_watches and watches->i_list)
60 * inotify_dev->sem (protects inotify_device and watches->d_list) 60 * inotify_dev->mutex (protects inotify_device and watches->d_list)
61 */ 61 */
62 62
63/* 63/*
@@ -79,12 +79,12 @@ int inotify_max_queued_events;
79/* 79/*
80 * struct inotify_device - represents an inotify instance 80 * struct inotify_device - represents an inotify instance
81 * 81 *
82 * This structure is protected by the semaphore 'sem'. 82 * This structure is protected by the mutex 'mutex'.
83 */ 83 */
84struct inotify_device { 84struct inotify_device {
85 wait_queue_head_t wq; /* wait queue for i/o */ 85 wait_queue_head_t wq; /* wait queue for i/o */
86 struct idr idr; /* idr mapping wd -> watch */ 86 struct idr idr; /* idr mapping wd -> watch */
87 struct semaphore sem; /* protects this bad boy */ 87 struct mutex mutex; /* protects this bad boy */
88 struct list_head events; /* list of queued events */ 88 struct list_head events; /* list of queued events */
89 struct list_head watches; /* list of watches */ 89 struct list_head watches; /* list of watches */
90 atomic_t count; /* reference count */ 90 atomic_t count; /* reference count */
@@ -101,7 +101,7 @@ struct inotify_device {
101 * device. In read(), this list is walked and all events that can fit in the 101 * device. In read(), this list is walked and all events that can fit in the
102 * buffer are returned. 102 * buffer are returned.
103 * 103 *
104 * Protected by dev->sem of the device in which we are queued. 104 * Protected by dev->mutex of the device in which we are queued.
105 */ 105 */
106struct inotify_kernel_event { 106struct inotify_kernel_event {
107 struct inotify_event event; /* the user-space event */ 107 struct inotify_event event; /* the user-space event */
@@ -112,8 +112,8 @@ struct inotify_kernel_event {
112/* 112/*
113 * struct inotify_watch - represents a watch request on a specific inode 113 * struct inotify_watch - represents a watch request on a specific inode
114 * 114 *
115 * d_list is protected by dev->sem of the associated watch->dev. 115 * d_list is protected by dev->mutex of the associated watch->dev.
116 * i_list and mask are protected by inode->inotify_sem of the associated inode. 116 * i_list and mask are protected by inode->inotify_mutex of the associated inode.
117 * dev, inode, and wd are never written to once the watch is created. 117 * dev, inode, and wd are never written to once the watch is created.
118 */ 118 */
119struct inotify_watch { 119struct inotify_watch {
@@ -261,7 +261,7 @@ static struct inotify_kernel_event * kernel_event(s32 wd, u32 mask, u32 cookie,
261/* 261/*
262 * inotify_dev_get_event - return the next event in the given dev's queue 262 * inotify_dev_get_event - return the next event in the given dev's queue
263 * 263 *
264 * Caller must hold dev->sem. 264 * Caller must hold dev->mutex.
265 */ 265 */
266static inline struct inotify_kernel_event * 266static inline struct inotify_kernel_event *
267inotify_dev_get_event(struct inotify_device *dev) 267inotify_dev_get_event(struct inotify_device *dev)
@@ -272,7 +272,7 @@ inotify_dev_get_event(struct inotify_device *dev)
272/* 272/*
273 * inotify_dev_queue_event - add a new event to the given device 273 * inotify_dev_queue_event - add a new event to the given device
274 * 274 *
275 * Caller must hold dev->sem. Can sleep (calls kernel_event()). 275 * Caller must hold dev->mutex. Can sleep (calls kernel_event()).
276 */ 276 */
277static void inotify_dev_queue_event(struct inotify_device *dev, 277static void inotify_dev_queue_event(struct inotify_device *dev,
278 struct inotify_watch *watch, u32 mask, 278 struct inotify_watch *watch, u32 mask,
@@ -315,7 +315,7 @@ static void inotify_dev_queue_event(struct inotify_device *dev,
315/* 315/*
316 * remove_kevent - cleans up and ultimately frees the given kevent 316 * remove_kevent - cleans up and ultimately frees the given kevent
317 * 317 *
318 * Caller must hold dev->sem. 318 * Caller must hold dev->mutex.
319 */ 319 */
320static void remove_kevent(struct inotify_device *dev, 320static void remove_kevent(struct inotify_device *dev,
321 struct inotify_kernel_event *kevent) 321 struct inotify_kernel_event *kevent)
@@ -332,7 +332,7 @@ static void remove_kevent(struct inotify_device *dev,
332/* 332/*
333 * inotify_dev_event_dequeue - destroy an event on the given device 333 * inotify_dev_event_dequeue - destroy an event on the given device
334 * 334 *
335 * Caller must hold dev->sem. 335 * Caller must hold dev->mutex.
336 */ 336 */
337static void inotify_dev_event_dequeue(struct inotify_device *dev) 337static void inotify_dev_event_dequeue(struct inotify_device *dev)
338{ 338{
@@ -346,7 +346,7 @@ static void inotify_dev_event_dequeue(struct inotify_device *dev)
346/* 346/*
347 * inotify_dev_get_wd - returns the next WD for use by the given dev 347 * inotify_dev_get_wd - returns the next WD for use by the given dev
348 * 348 *
349 * Callers must hold dev->sem. This function can sleep. 349 * Callers must hold dev->mutex. This function can sleep.
350 */ 350 */
351static int inotify_dev_get_wd(struct inotify_device *dev, 351static int inotify_dev_get_wd(struct inotify_device *dev,
352 struct inotify_watch *watch) 352 struct inotify_watch *watch)
@@ -383,7 +383,7 @@ static int find_inode(const char __user *dirname, struct nameidata *nd,
383/* 383/*
384 * create_watch - creates a watch on the given device. 384 * create_watch - creates a watch on the given device.
385 * 385 *
386 * Callers must hold dev->sem. Calls inotify_dev_get_wd() so may sleep. 386 * Callers must hold dev->mutex. Calls inotify_dev_get_wd() so may sleep.
387 * Both 'dev' and 'inode' (by way of nameidata) need to be pinned. 387 * Both 'dev' and 'inode' (by way of nameidata) need to be pinned.
388 */ 388 */
389static struct inotify_watch *create_watch(struct inotify_device *dev, 389static struct inotify_watch *create_watch(struct inotify_device *dev,
@@ -434,7 +434,7 @@ static struct inotify_watch *create_watch(struct inotify_device *dev,
434/* 434/*
435 * inotify_find_dev - find the watch associated with the given inode and dev 435 * inotify_find_dev - find the watch associated with the given inode and dev
436 * 436 *
437 * Callers must hold inode->inotify_sem. 437 * Callers must hold inode->inotify_mutex.
438 */ 438 */
439static struct inotify_watch *inode_find_dev(struct inode *inode, 439static struct inotify_watch *inode_find_dev(struct inode *inode,
440 struct inotify_device *dev) 440 struct inotify_device *dev)
@@ -469,7 +469,7 @@ static void remove_watch_no_event(struct inotify_watch *watch,
469 * the IN_IGNORED event to the given device signifying that the inode is no 469 * the IN_IGNORED event to the given device signifying that the inode is no
470 * longer watched. 470 * longer watched.
471 * 471 *
472 * Callers must hold both inode->inotify_sem and dev->sem. We drop a 472 * Callers must hold both inode->inotify_mutex and dev->mutex. We drop a
473 * reference to the inode before returning. 473 * reference to the inode before returning.
474 * 474 *
475 * The inode is not iput() so as to remain atomic. If the inode needs to be 475 * The inode is not iput() so as to remain atomic. If the inode needs to be
@@ -507,21 +507,21 @@ void inotify_inode_queue_event(struct inode *inode, u32 mask, u32 cookie,
507 if (!inotify_inode_watched(inode)) 507 if (!inotify_inode_watched(inode))
508 return; 508 return;
509 509
510 down(&inode->inotify_sem); 510 mutex_lock(&inode->inotify_mutex);
511 list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) { 511 list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) {
512 u32 watch_mask = watch->mask; 512 u32 watch_mask = watch->mask;
513 if (watch_mask & mask) { 513 if (watch_mask & mask) {
514 struct inotify_device *dev = watch->dev; 514 struct inotify_device *dev = watch->dev;
515 get_inotify_watch(watch); 515 get_inotify_watch(watch);
516 down(&dev->sem); 516 mutex_lock(&dev->mutex);
517 inotify_dev_queue_event(dev, watch, mask, cookie, name); 517 inotify_dev_queue_event(dev, watch, mask, cookie, name);
518 if (watch_mask & IN_ONESHOT) 518 if (watch_mask & IN_ONESHOT)
519 remove_watch_no_event(watch, dev); 519 remove_watch_no_event(watch, dev);
520 up(&dev->sem); 520 mutex_unlock(&dev->mutex);
521 put_inotify_watch(watch); 521 put_inotify_watch(watch);
522 } 522 }
523 } 523 }
524 up(&inode->inotify_sem); 524 mutex_unlock(&inode->inotify_mutex);
525} 525}
526EXPORT_SYMBOL_GPL(inotify_inode_queue_event); 526EXPORT_SYMBOL_GPL(inotify_inode_queue_event);
527 527
@@ -569,7 +569,7 @@ EXPORT_SYMBOL_GPL(inotify_get_cookie);
569 * @list: list of inodes being unmounted (sb->s_inodes) 569 * @list: list of inodes being unmounted (sb->s_inodes)
570 * 570 *
571 * Called with inode_lock held, protecting the unmounting super block's list 571 * Called with inode_lock held, protecting the unmounting super block's list
572 * of inodes, and with iprune_sem held, keeping shrink_icache_memory() at bay. 572 * of inodes, and with iprune_mutex held, keeping shrink_icache_memory() at bay.
573 * We temporarily drop inode_lock, however, and CAN block. 573 * We temporarily drop inode_lock, however, and CAN block.
574 */ 574 */
575void inotify_unmount_inodes(struct list_head *list) 575void inotify_unmount_inodes(struct list_head *list)
@@ -618,7 +618,7 @@ void inotify_unmount_inodes(struct list_head *list)
618 * We can safely drop inode_lock here because we hold 618 * We can safely drop inode_lock here because we hold
619 * references on both inode and next_i. Also no new inodes 619 * references on both inode and next_i. Also no new inodes
620 * will be added since the umount has begun. Finally, 620 * will be added since the umount has begun. Finally,
621 * iprune_sem keeps shrink_icache_memory() away. 621 * iprune_mutex keeps shrink_icache_memory() away.
622 */ 622 */
623 spin_unlock(&inode_lock); 623 spin_unlock(&inode_lock);
624 624
@@ -626,16 +626,16 @@ void inotify_unmount_inodes(struct list_head *list)
626 iput(need_iput_tmp); 626 iput(need_iput_tmp);
627 627
628 /* for each watch, send IN_UNMOUNT and then remove it */ 628 /* for each watch, send IN_UNMOUNT and then remove it */
629 down(&inode->inotify_sem); 629 mutex_lock(&inode->inotify_mutex);
630 watches = &inode->inotify_watches; 630 watches = &inode->inotify_watches;
631 list_for_each_entry_safe(watch, next_w, watches, i_list) { 631 list_for_each_entry_safe(watch, next_w, watches, i_list) {
632 struct inotify_device *dev = watch->dev; 632 struct inotify_device *dev = watch->dev;
633 down(&dev->sem); 633 mutex_lock(&dev->mutex);
634 inotify_dev_queue_event(dev, watch, IN_UNMOUNT,0,NULL); 634 inotify_dev_queue_event(dev, watch, IN_UNMOUNT,0,NULL);
635 remove_watch(watch, dev); 635 remove_watch(watch, dev);
636 up(&dev->sem); 636 mutex_unlock(&dev->mutex);
637 } 637 }
638 up(&inode->inotify_sem); 638 mutex_unlock(&inode->inotify_mutex);
639 iput(inode); 639 iput(inode);
640 640
641 spin_lock(&inode_lock); 641 spin_lock(&inode_lock);
@@ -651,14 +651,14 @@ void inotify_inode_is_dead(struct inode *inode)
651{ 651{
652 struct inotify_watch *watch, *next; 652 struct inotify_watch *watch, *next;
653 653
654 down(&inode->inotify_sem); 654 mutex_lock(&inode->inotify_mutex);
655 list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) { 655 list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) {
656 struct inotify_device *dev = watch->dev; 656 struct inotify_device *dev = watch->dev;
657 down(&dev->sem); 657 mutex_lock(&dev->mutex);
658 remove_watch(watch, dev); 658 remove_watch(watch, dev);
659 up(&dev->sem); 659 mutex_unlock(&dev->mutex);
660 } 660 }
661 up(&inode->inotify_sem); 661 mutex_unlock(&inode->inotify_mutex);
662} 662}
663EXPORT_SYMBOL_GPL(inotify_inode_is_dead); 663EXPORT_SYMBOL_GPL(inotify_inode_is_dead);
664 664
@@ -670,10 +670,10 @@ static unsigned int inotify_poll(struct file *file, poll_table *wait)
670 int ret = 0; 670 int ret = 0;
671 671
672 poll_wait(file, &dev->wq, wait); 672 poll_wait(file, &dev->wq, wait);
673 down(&dev->sem); 673 mutex_lock(&dev->mutex);
674 if (!list_empty(&dev->events)) 674 if (!list_empty(&dev->events))
675 ret = POLLIN | POLLRDNORM; 675 ret = POLLIN | POLLRDNORM;
676 up(&dev->sem); 676 mutex_unlock(&dev->mutex);
677 677
678 return ret; 678 return ret;
679} 679}
@@ -695,9 +695,9 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
695 695
696 prepare_to_wait(&dev->wq, &wait, TASK_INTERRUPTIBLE); 696 prepare_to_wait(&dev->wq, &wait, TASK_INTERRUPTIBLE);
697 697
698 down(&dev->sem); 698 mutex_lock(&dev->mutex);
699 events = !list_empty(&dev->events); 699 events = !list_empty(&dev->events);
700 up(&dev->sem); 700 mutex_unlock(&dev->mutex);
701 if (events) { 701 if (events) {
702 ret = 0; 702 ret = 0;
703 break; 703 break;
@@ -720,7 +720,7 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
720 if (ret) 720 if (ret)
721 return ret; 721 return ret;
722 722
723 down(&dev->sem); 723 mutex_lock(&dev->mutex);
724 while (1) { 724 while (1) {
725 struct inotify_kernel_event *kevent; 725 struct inotify_kernel_event *kevent;
726 726
@@ -750,7 +750,7 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
750 750
751 remove_kevent(dev, kevent); 751 remove_kevent(dev, kevent);
752 } 752 }
753 up(&dev->sem); 753 mutex_unlock(&dev->mutex);
754 754
755 return ret; 755 return ret;
756} 756}
@@ -763,37 +763,37 @@ static int inotify_release(struct inode *ignored, struct file *file)
763 * Destroy all of the watches on this device. Unfortunately, not very 763 * Destroy all of the watches on this device. Unfortunately, not very
764 * pretty. We cannot do a simple iteration over the list, because we 764 * pretty. We cannot do a simple iteration over the list, because we
765 * do not know the inode until we iterate to the watch. But we need to 765 * do not know the inode until we iterate to the watch. But we need to
766 * hold inode->inotify_sem before dev->sem. The following works. 766 * hold inode->inotify_mutex before dev->mutex. The following works.
767 */ 767 */
768 while (1) { 768 while (1) {
769 struct inotify_watch *watch; 769 struct inotify_watch *watch;
770 struct list_head *watches; 770 struct list_head *watches;
771 struct inode *inode; 771 struct inode *inode;
772 772
773 down(&dev->sem); 773 mutex_lock(&dev->mutex);
774 watches = &dev->watches; 774 watches = &dev->watches;
775 if (list_empty(watches)) { 775 if (list_empty(watches)) {
776 up(&dev->sem); 776 mutex_unlock(&dev->mutex);
777 break; 777 break;
778 } 778 }
779 watch = list_entry(watches->next, struct inotify_watch, d_list); 779 watch = list_entry(watches->next, struct inotify_watch, d_list);
780 get_inotify_watch(watch); 780 get_inotify_watch(watch);
781 up(&dev->sem); 781 mutex_unlock(&dev->mutex);
782 782
783 inode = watch->inode; 783 inode = watch->inode;
784 down(&inode->inotify_sem); 784 mutex_lock(&inode->inotify_mutex);
785 down(&dev->sem); 785 mutex_lock(&dev->mutex);
786 remove_watch_no_event(watch, dev); 786 remove_watch_no_event(watch, dev);
787 up(&dev->sem); 787 mutex_unlock(&dev->mutex);
788 up(&inode->inotify_sem); 788 mutex_unlock(&inode->inotify_mutex);
789 put_inotify_watch(watch); 789 put_inotify_watch(watch);
790 } 790 }
791 791
792 /* destroy all of the events on this device */ 792 /* destroy all of the events on this device */
793 down(&dev->sem); 793 mutex_lock(&dev->mutex);
794 while (!list_empty(&dev->events)) 794 while (!list_empty(&dev->events))
795 inotify_dev_event_dequeue(dev); 795 inotify_dev_event_dequeue(dev);
796 up(&dev->sem); 796 mutex_unlock(&dev->mutex);
797 797
798 /* free this device: the put matching the get in inotify_init() */ 798 /* free this device: the put matching the get in inotify_init() */
799 put_inotify_dev(dev); 799 put_inotify_dev(dev);
@@ -811,26 +811,26 @@ static int inotify_ignore(struct inotify_device *dev, s32 wd)
811 struct inotify_watch *watch; 811 struct inotify_watch *watch;
812 struct inode *inode; 812 struct inode *inode;
813 813
814 down(&dev->sem); 814 mutex_lock(&dev->mutex);
815 watch = idr_find(&dev->idr, wd); 815 watch = idr_find(&dev->idr, wd);
816 if (unlikely(!watch)) { 816 if (unlikely(!watch)) {
817 up(&dev->sem); 817 mutex_unlock(&dev->mutex);
818 return -EINVAL; 818 return -EINVAL;
819 } 819 }
820 get_inotify_watch(watch); 820 get_inotify_watch(watch);
821 inode = watch->inode; 821 inode = watch->inode;
822 up(&dev->sem); 822 mutex_unlock(&dev->mutex);
823 823
824 down(&inode->inotify_sem); 824 mutex_lock(&inode->inotify_mutex);
825 down(&dev->sem); 825 mutex_lock(&dev->mutex);
826 826
827 /* make sure that we did not race */ 827 /* make sure that we did not race */
828 watch = idr_find(&dev->idr, wd); 828 watch = idr_find(&dev->idr, wd);
829 if (likely(watch)) 829 if (likely(watch))
830 remove_watch(watch, dev); 830 remove_watch(watch, dev);
831 831
832 up(&dev->sem); 832 mutex_unlock(&dev->mutex);
833 up(&inode->inotify_sem); 833 mutex_unlock(&inode->inotify_mutex);
834 put_inotify_watch(watch); 834 put_inotify_watch(watch);
835 835
836 return 0; 836 return 0;
@@ -905,7 +905,7 @@ asmlinkage long sys_inotify_init(void)
905 INIT_LIST_HEAD(&dev->events); 905 INIT_LIST_HEAD(&dev->events);
906 INIT_LIST_HEAD(&dev->watches); 906 INIT_LIST_HEAD(&dev->watches);
907 init_waitqueue_head(&dev->wq); 907 init_waitqueue_head(&dev->wq);
908 sema_init(&dev->sem, 1); 908 mutex_init(&dev->mutex);
909 dev->event_count = 0; 909 dev->event_count = 0;
910 dev->queue_size = 0; 910 dev->queue_size = 0;
911 dev->max_events = inotify_max_queued_events; 911 dev->max_events = inotify_max_queued_events;
@@ -960,8 +960,8 @@ asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
960 inode = nd.dentry->d_inode; 960 inode = nd.dentry->d_inode;
961 dev = filp->private_data; 961 dev = filp->private_data;
962 962
963 down(&inode->inotify_sem); 963 mutex_lock(&inode->inotify_mutex);
964 down(&dev->sem); 964 mutex_lock(&dev->mutex);
965 965
966 if (mask & IN_MASK_ADD) 966 if (mask & IN_MASK_ADD)
967 mask_add = 1; 967 mask_add = 1;
@@ -998,8 +998,8 @@ asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
998 list_add(&watch->i_list, &inode->inotify_watches); 998 list_add(&watch->i_list, &inode->inotify_watches);
999 ret = watch->wd; 999 ret = watch->wd;
1000out: 1000out:
1001 up(&dev->sem); 1001 mutex_unlock(&dev->mutex);
1002 up(&inode->inotify_sem); 1002 mutex_unlock(&inode->inotify_mutex);
1003 path_release(&nd); 1003 path_release(&nd);
1004fput_and_out: 1004fput_and_out:
1005 fput_light(filp, fput_needed); 1005 fput_light(filp, fput_needed);