diff options
| -rw-r--r-- | fs/dcache.c | 27 | ||||
| -rw-r--r-- | fs/debugfs/inode.c | 10 | ||||
| -rw-r--r-- | fs/namei.c | 8 | ||||
| -rw-r--r-- | fs/notify/fsnotify.c | 8 | ||||
| -rw-r--r-- | include/linux/dcache.h | 6 | ||||
| -rw-r--r-- | include/linux/fsnotify.h | 31 |
6 files changed, 48 insertions, 42 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 1dbc6b560fef..67957f5b325c 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -277,6 +277,33 @@ static inline int dname_external(const struct dentry *dentry) return dentry->d_name.name != dentry->d_iname; } +void take_dentry_name_snapshot(struct name_snapshot *name, struct dentry *dentry) +{ + spin_lock(&dentry->d_lock); + if (unlikely(dname_external(dentry))) { + struct external_name *p = external_name(dentry); + atomic_inc(&p->u.count); + spin_unlock(&dentry->d_lock); + name->name = p->name; + } else { + memcpy(name->inline_name, dentry->d_iname, DNAME_INLINE_LEN); + spin_unlock(&dentry->d_lock); + name->name = name->inline_name; + } +} +EXPORT_SYMBOL(take_dentry_name_snapshot); + +void release_dentry_name_snapshot(struct name_snapshot *name) +{ + if (unlikely(name->name != name->inline_name)) { + struct external_name *p; + p = container_of(name->name, struct external_name, name[0]); + if (unlikely(atomic_dec_and_test(&p->u.count))) + kfree_rcu(p, u.head); + } +} +EXPORT_SYMBOL(release_dentry_name_snapshot); + static inline void __d_set_inode_and_type(struct dentry *dentry, struct inode *inode, unsigned type_flags) diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 1e30f74a9527..3d7de9f4f545 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -730,7 +730,7 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, { int error; struct dentry *dentry = NULL, *trap; - const char *old_name; + struct name_snapshot old_name; trap = lock_rename(new_dir, old_dir); /* Source or destination directories don't exist? */ @@ -745,19 +745,19 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, if (IS_ERR(dentry) || dentry == trap || d_really_is_positive(dentry)) goto exit; - old_name = fsnotify_oldname_init(old_dentry->d_name.name); + take_dentry_name_snapshot(&old_name, old_dentry); error = simple_rename(d_inode(old_dir), old_dentry, d_inode(new_dir), dentry, 0); if (error) { - fsnotify_oldname_free(old_name); + release_dentry_name_snapshot(&old_name); goto exit; } d_move(old_dentry, dentry); - fsnotify_move(d_inode(old_dir), d_inode(new_dir), old_name, + fsnotify_move(d_inode(old_dir), d_inode(new_dir), old_name.name, d_is_dir(old_dentry), NULL, old_dentry); - fsnotify_oldname_free(old_name); + release_dentry_name_snapshot(&old_name); unlock_rename(new_dir, old_dir); dput(dentry); return old_dentry; diff --git a/fs/namei.c b/fs/namei.c index d5e5140c1045..66209f720146 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -4336,11 +4336,11 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, { int error; bool is_dir = d_is_dir(old_dentry); - const unsigned char *old_name; struct inode *source = old_dentry->d_inode; struct inode *target = new_dentry->d_inode; bool new_is_dir = false; unsigned max_links = new_dir->i_sb->s_max_links; + struct name_snapshot old_name; /* * Check source == target. @@ -4391,7 +4391,7 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, if (error) return error; - old_name = fsnotify_oldname_init(old_dentry->d_name.name); + take_dentry_name_snapshot(&old_name, old_dentry); dget(new_dentry); if (!is_dir || (flags & RENAME_EXCHANGE)) lock_two_nondirectories(source, target); @@ -4446,14 +4446,14 @@ out: inode_unlock(target); dput(new_dentry); if (!error) { - fsnotify_move(old_dir, new_dir, old_name, is_dir, + fsnotify_move(old_dir, new_dir, old_name.name, is_dir, !(flags & RENAME_EXCHANGE) ? target : NULL, old_dentry); if (flags & RENAME_EXCHANGE) { fsnotify_move(new_dir, old_dir, old_dentry->d_name.name, new_is_dir, NULL, new_dentry); } } - fsnotify_oldname_free(old_name); + release_dentry_name_snapshot(&old_name); return error; } diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index db39de2dd4cb..a64adc2fced9 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -104,16 +104,20 @@ int __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask) if (unlikely(!fsnotify_inode_watches_children(p_inode))) __fsnotify_update_child_dentry_flags(p_inode); else if (p_inode->i_fsnotify_mask & mask) { + struct name_snapshot name; + /* we are notifying a parent so come up with the new mask which * specifies these are events which came from a child. */ mask |= FS_EVENT_ON_CHILD; + take_dentry_name_snapshot(&name, dentry); if (path) ret = fsnotify(p_inode, mask, path, FSNOTIFY_EVENT_PATH, - dentry->d_name.name, 0); + name.name, 0); else ret = fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE, - dentry->d_name.name, 0); + name.name, 0); + release_dentry_name_snapshot(&name); } dput(parent); diff --git a/include/linux/dcache.h b/include/linux/dcache.h index 5beed7b30561..ff295e166b2c 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -590,5 +590,11 @@ static inline struct inode *d_real_inode(const struct dentry *dentry) return d_backing_inode(d_real((struct dentry *) dentry, NULL, 0)); } +struct name_snapshot { + const char *name; + char inline_name[DNAME_INLINE_LEN]; +}; +void take_dentry_name_snapshot(struct name_snapshot *, struct dentry *); +void release_dentry_name_snapshot(struct name_snapshot *); #endif /* __LINUX_DCACHE_H */ diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h index b8bcc058e031..e5f03a4d8430 100644 --- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -293,35 +293,4 @@ static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid) } } -#if defined(CONFIG_FSNOTIFY) /* notify helpers */ - -/* - * fsnotify_oldname_init - save off the old filename before we change it - */ -static inline const unsigned char *fsnotify_oldname_init(const unsigned char *name) -{ - return kstrdup(name, GFP_KERNEL); -} - -/* - * fsnotify_oldname_free - free the name we got from fsnotify_oldname_init - */ -static inline void fsnotify_oldname_free(const unsigned char *old_name) -{ - kfree(old_name); -} - -#else /* CONFIG_FSNOTIFY */ - -static inline const char *fsnotify_oldname_init(const unsigned char *name) -{ - return NULL; -} - -static inline void fsnotify_oldname_free(const unsigned char *old_name) -{ -} - -#endif /* CONFIG_FSNOTIFY */ - #endif /* _LINUX_FS_NOTIFY_H */ |