diff options
| -rw-r--r-- | fs/inode.c | 1 | ||||
| -rw-r--r-- | fs/notify/inode_mark.c | 72 | ||||
| -rw-r--r-- | include/linux/fsnotify_backend.h | 4 |
3 files changed, 77 insertions, 0 deletions
diff --git a/fs/inode.c b/fs/inode.c index 54c63ce3de2..ca337014ae2 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -407,6 +407,7 @@ int invalidate_inodes(struct super_block *sb) mutex_lock(&iprune_mutex); spin_lock(&inode_lock); inotify_unmount_inodes(&sb->s_inodes); + fsnotify_unmount_inodes(&sb->s_inodes); busy = invalidate_list(&sb->s_inodes, &throw_away); spin_unlock(&inode_lock); diff --git a/fs/notify/inode_mark.c b/fs/notify/inode_mark.c index 282150f74cf..0a499d2c619 100644 --- a/fs/notify/inode_mark.c +++ b/fs/notify/inode_mark.c @@ -89,6 +89,7 @@ #include <linux/mutex.h> #include <linux/slab.h> #include <linux/spinlock.h> +#include <linux/writeback.h> /* for inode_lock */ #include <asm/atomic.h> @@ -351,3 +352,74 @@ int fsnotify_add_mark(struct fsnotify_mark_entry *entry, return ret; } + +/** + * fsnotify_unmount_inodes - an sb is unmounting. handle any watched inodes. + * @list: list of inodes being unmounted (sb->s_inodes) + * + * Called with inode_lock held, protecting the unmounting super block's list + * of inodes, and with iprune_mutex held, keeping shrink_icache_memory() at bay. + * We temporarily drop inode_lock, however, and CAN block. + */ +void fsnotify_unmount_inodes(struct list_head *list) +{ + struct inode *inode, *next_i, *need_iput = NULL; + + list_for_each_entry_safe(inode, next_i, list, i_sb_list) { + struct inode *need_iput_tmp; + + /* + * We cannot __iget() an inode in state I_CLEAR, I_FREEING, + * I_WILL_FREE, or I_NEW which is fine because by that point + * the inode cannot have any associated watches. + */ + if (inode->i_state & (I_CLEAR|I_FREEING|I_WILL_FREE|I_NEW)) + continue; + + /* + * If i_count is zero, the inode cannot have any watches and + * doing an __iget/iput with MS_ACTIVE clear would actually + * evict all inodes with zero i_count from icache which is + * unnecessarily violent and may in fact be illegal to do. + */ + if (!atomic_read(&inode->i_count)) + continue; + + need_iput_tmp = need_iput; + need_iput = NULL; + + /* In case fsnotify_inode_delete() drops a reference. */ + if (inode != need_iput_tmp) + __iget(inode); + else + need_iput_tmp = NULL; + + /* In case the dropping of a reference would nuke next_i. */ + if ((&next_i->i_sb_list != list) && + atomic_read(&next_i->i_count) && + !(next_i->i_state & (I_CLEAR | I_FREEING | I_WILL_FREE))) { + __iget(next_i); + need_iput = next_i; + } + + /* + * We can safely drop inode_lock here because we hold + * references on both inode and next_i. Also no new inodes + * will be added since the umount has begun. Finally, + * iprune_mutex keeps shrink_icache_memory() away. + */ + spin_unlock(&inode_lock); + + if (need_iput_tmp) + iput(need_iput_tmp); + + /* for each watch, send FS_UNMOUNT and then remove it */ + fsnotify(inode, FS_UNMOUNT, inode, FSNOTIFY_EVENT_INODE, NULL, 0); + + fsnotify_inode_delete(inode); + + iput(inode); + + spin_lock(&inode_lock); + } +} diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index efdf9e442d8..d2c0ee30e61 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -336,6 +336,7 @@ extern void fsnotify_destroy_mark_by_entry(struct fsnotify_mark_entry *entry); extern void fsnotify_clear_marks_by_group(struct fsnotify_group *group); extern void fsnotify_get_mark(struct fsnotify_mark_entry *entry); extern void fsnotify_put_mark(struct fsnotify_mark_entry *entry); +extern void fsnotify_unmount_inodes(struct list_head *list); /* put here because inotify does some weird stuff when destroying watches */ extern struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u32 mask, @@ -365,6 +366,9 @@ static inline u32 fsnotify_get_cookie(void) return 0; } +static inline void fsnotify_unmount_inodes(struct list_head *list) +{} + #endif /* CONFIG_FSNOTIFY */ #endif /* __KERNEL __ */ |