From ec4f860597af41c6b71f4de86d8e86f710bfab54 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 5 Jan 2010 13:45:18 -0700 Subject: fs/dcache.c: CodingStyle cleanup Cleanup EXPORT* macros according to Documantation/CodingStyle. Move EXPORT* macros to the line immediately after the closing function brace. Signed-off-by: H Hartley Sweeten Signed-off-by: Al Viro --- fs/dcache.c | 45 ++++++++++++++++++++++----------------------- 1 file changed, 22 insertions(+), 23 deletions(-) (limited to 'fs/dcache.c') diff --git a/fs/dcache.c b/fs/dcache.c index 953173a293a9..4365998b8df4 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -257,6 +257,7 @@ kill_it: if (dentry) goto repeat; } +EXPORT_SYMBOL(dput); /** * d_invalidate - invalidate a dentry @@ -314,6 +315,7 @@ int d_invalidate(struct dentry * dentry) spin_unlock(&dcache_lock); return 0; } +EXPORT_SYMBOL(d_invalidate); /* This should be called _only_ with dcache_lock held */ @@ -328,6 +330,7 @@ struct dentry * dget_locked(struct dentry *dentry) { return __dget_locked(dentry); } +EXPORT_SYMBOL(dget_locked); /** * d_find_alias - grab a hashed alias of inode @@ -384,6 +387,7 @@ struct dentry * d_find_alias(struct inode *inode) } return de; } +EXPORT_SYMBOL(d_find_alias); /* * Try to kill dentries associated with this inode. @@ -408,6 +412,7 @@ restart: } spin_unlock(&dcache_lock); } +EXPORT_SYMBOL(d_prune_aliases); /* * Throw away a dentry - free the inode, dput the parent. This requires that @@ -610,6 +615,7 @@ void shrink_dcache_sb(struct super_block * sb) { __shrink_dcache_sb(sb, NULL, 0); } +EXPORT_SYMBOL(shrink_dcache_sb); /* * destroy a single subtree of dentries for unmount @@ -792,6 +798,7 @@ positive: spin_unlock(&dcache_lock); return 1; } +EXPORT_SYMBOL(have_submounts); /* * Search the dentry child list for the specified parent, @@ -876,6 +883,7 @@ void shrink_dcache_parent(struct dentry * parent) while ((found = select_parent(parent)) != 0) __shrink_dcache_sb(sb, &found, 0); } +EXPORT_SYMBOL(shrink_dcache_parent); /* * Scan `nr' dentries and return the number which remain. @@ -968,6 +976,7 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name) return dentry; } +EXPORT_SYMBOL(d_alloc); struct dentry *d_alloc_name(struct dentry *parent, const char *name) { @@ -1012,6 +1021,7 @@ void d_instantiate(struct dentry *entry, struct inode * inode) spin_unlock(&dcache_lock); security_d_instantiate(entry, inode); } +EXPORT_SYMBOL(d_instantiate); /** * d_instantiate_unique - instantiate a non-aliased dentry @@ -1108,6 +1118,7 @@ struct dentry * d_alloc_root(struct inode * root_inode) } return res; } +EXPORT_SYMBOL(d_alloc_root); static inline struct hlist_head *d_hash(struct dentry *parent, unsigned long hash) @@ -1225,6 +1236,7 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) d_add(dentry, inode); return new; } +EXPORT_SYMBOL(d_splice_alias); /** * d_add_ci - lookup or allocate new dentry with case-exact name @@ -1314,6 +1326,7 @@ err_out: iput(inode); return ERR_PTR(error); } +EXPORT_SYMBOL(d_add_ci); /** * d_lookup - search for a dentry @@ -1357,6 +1370,7 @@ struct dentry * d_lookup(struct dentry * parent, struct qstr * name) } while (read_seqretry(&rename_lock, seq)); return dentry; } +EXPORT_SYMBOL(d_lookup); struct dentry * __d_lookup(struct dentry * parent, struct qstr * name) { @@ -1483,6 +1497,7 @@ int d_validate(struct dentry *dentry, struct dentry *dparent) out: return 0; } +EXPORT_SYMBOL(d_validate); /* * When a file is deleted, we have two options: @@ -1528,6 +1543,7 @@ void d_delete(struct dentry * dentry) fsnotify_nameremove(dentry, isdir); } +EXPORT_SYMBOL(d_delete); static void __d_rehash(struct dentry * entry, struct hlist_head *list) { @@ -1556,6 +1572,7 @@ void d_rehash(struct dentry * entry) spin_unlock(&entry->d_lock); spin_unlock(&dcache_lock); } +EXPORT_SYMBOL(d_rehash); /* * When switching names, the actual string doesn't strictly have to @@ -1702,6 +1719,7 @@ void d_move(struct dentry * dentry, struct dentry * target) d_move_locked(dentry, target); spin_unlock(&dcache_lock); } +EXPORT_SYMBOL(d_move); /** * d_ancestor - search for an ancestor @@ -1868,6 +1886,7 @@ shouldnt_be_hashed: spin_unlock(&dcache_lock); BUG(); } +EXPORT_SYMBOL_GPL(d_materialise_unique); static int prepend(char **buffer, int *buflen, const char *str, int namelen) { @@ -2005,6 +2024,7 @@ char *d_path(const struct path *path, char *buf, int buflen) path_put(&root); return res; } +EXPORT_SYMBOL(d_path); /* * Helper function for dentry_operations.d_dname() members @@ -2228,6 +2248,7 @@ ino_t find_inode_number(struct dentry *dir, struct qstr *name) } return ino; } +EXPORT_SYMBOL(find_inode_number); static __initdata unsigned long dhash_entries; static int __init set_dhash_entries(char *str) @@ -2297,6 +2318,7 @@ static void __init dcache_init(void) /* SLAB cache for __getname() consumers */ struct kmem_cache *names_cachep __read_mostly; +EXPORT_SYMBOL(names_cachep); EXPORT_SYMBOL(d_genocide); @@ -2326,26 +2348,3 @@ void __init vfs_caches_init(unsigned long mempages) bdev_cache_init(); chrdev_init(); } - -EXPORT_SYMBOL(d_alloc); -EXPORT_SYMBOL(d_alloc_root); -EXPORT_SYMBOL(d_delete); -EXPORT_SYMBOL(d_find_alias); -EXPORT_SYMBOL(d_instantiate); -EXPORT_SYMBOL(d_invalidate); -EXPORT_SYMBOL(d_lookup); -EXPORT_SYMBOL(d_move); -EXPORT_SYMBOL_GPL(d_materialise_unique); -EXPORT_SYMBOL(d_path); -EXPORT_SYMBOL(d_prune_aliases); -EXPORT_SYMBOL(d_rehash); -EXPORT_SYMBOL(d_splice_alias); -EXPORT_SYMBOL(d_add_ci); -EXPORT_SYMBOL(d_validate); -EXPORT_SYMBOL(dget_locked); -EXPORT_SYMBOL(dput); -EXPORT_SYMBOL(find_inode_number); -EXPORT_SYMBOL(have_submounts); -EXPORT_SYMBOL(names_cachep); -EXPORT_SYMBOL(shrink_dcache_parent); -EXPORT_SYMBOL(shrink_dcache_sb); -- cgit v1.2.3 From 2096f759abcb42200a81d776f597362fd9265024 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 30 Jan 2010 13:16:21 -0500 Subject: New helper: path_is_under(path1, path2) Analog of is_subdir for vfsmount,dentry pairs, moved from audit_tree.c Signed-off-by: Al Viro --- fs/dcache.c | 24 ++++++++++++++++++++++++ include/linux/fs.h | 1 + kernel/audit_tree.c | 51 ++++++++++++--------------------------------------- 3 files changed, 37 insertions(+), 39 deletions(-) (limited to 'fs/dcache.c') diff --git a/fs/dcache.c b/fs/dcache.c index 4365998b8df4..74da947b160b 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2191,6 +2191,30 @@ int is_subdir(struct dentry *new_dentry, struct dentry *old_dentry) return result; } +int path_is_under(struct path *path1, struct path *path2) +{ + struct vfsmount *mnt = path1->mnt; + struct dentry *dentry = path1->dentry; + int res; + spin_lock(&vfsmount_lock); + if (mnt != path2->mnt) { + for (;;) { + if (mnt->mnt_parent == mnt) { + spin_unlock(&vfsmount_lock); + return 0; + } + if (mnt->mnt_parent == path2->mnt) + break; + mnt = mnt->mnt_parent; + } + dentry = mnt->mnt_mountpoint; + } + res = is_subdir(dentry, path2->dentry); + spin_unlock(&vfsmount_lock); + return res; +} +EXPORT_SYMBOL(path_is_under); + void d_genocide(struct dentry *root) { struct dentry *this_parent = root; diff --git a/include/linux/fs.h b/include/linux/fs.h index d443c9dd3caa..8d53bc17f93f 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2126,6 +2126,7 @@ extern struct file * open_exec(const char *); /* fs/dcache.c -- generic fs support functions */ extern int is_subdir(struct dentry *, struct dentry *); +extern int path_is_under(struct path *, struct path *); extern ino_t find_inode_number(struct dentry *, struct qstr *); #include diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 4b05bd9479db..f09b42d9c32d 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -603,22 +603,6 @@ skip_it: mutex_unlock(&audit_filter_mutex); } -static int is_under(struct vfsmount *mnt, struct dentry *dentry, - struct path *path) -{ - if (mnt != path->mnt) { - for (;;) { - if (mnt->mnt_parent == mnt) - return 0; - if (mnt->mnt_parent == path->mnt) - break; - mnt = mnt->mnt_parent; - } - dentry = mnt->mnt_mountpoint; - } - return is_subdir(dentry, path->dentry); -} - int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op) { @@ -714,29 +698,24 @@ int audit_tag_tree(char *old, char *new) { struct list_head cursor, barrier; int failed = 0; - struct path path; + struct path path1, path2; struct vfsmount *tagged; struct list_head list; - struct vfsmount *mnt; - struct dentry *dentry; int err; - err = kern_path(new, 0, &path); + err = kern_path(new, 0, &path2); if (err) return err; - tagged = collect_mounts(&path); - path_put(&path); + tagged = collect_mounts(&path2); + path_put(&path2); if (!tagged) return -ENOMEM; - err = kern_path(old, 0, &path); + err = kern_path(old, 0, &path1); if (err) { drop_collected_mounts(tagged); return err; } - mnt = mntget(path.mnt); - dentry = dget(path.dentry); - path_put(&path); list_add_tail(&list, &tagged->mnt_list); @@ -747,6 +726,7 @@ int audit_tag_tree(char *old, char *new) while (cursor.next != &tree_list) { struct audit_tree *tree; struct vfsmount *p; + int good_one = 0; tree = container_of(cursor.next, struct audit_tree, list); get_tree(tree); @@ -754,23 +734,17 @@ int audit_tag_tree(char *old, char *new) list_add(&cursor, &tree->list); mutex_unlock(&audit_filter_mutex); - err = kern_path(tree->pathname, 0, &path); - if (err) { - put_tree(tree); - mutex_lock(&audit_filter_mutex); - continue; + err = kern_path(tree->pathname, 0, &path2); + if (!err) { + good_one = path_is_under(&path1, &path2); + path_put(&path2); } - spin_lock(&vfsmount_lock); - if (!is_under(mnt, dentry, &path)) { - spin_unlock(&vfsmount_lock); - path_put(&path); + if (!good_one) { put_tree(tree); mutex_lock(&audit_filter_mutex); continue; } - spin_unlock(&vfsmount_lock); - path_put(&path); list_for_each_entry(p, &list, mnt_list) { failed = tag_chunk(p->mnt_root->d_inode, tree); @@ -820,8 +794,7 @@ int audit_tag_tree(char *old, char *new) list_del(&cursor); list_del(&list); mutex_unlock(&audit_filter_mutex); - dput(dentry); - mntput(mnt); + path_put(&path1); drop_collected_mounts(tagged); return failed; } -- cgit v1.2.3 From 4919c5e45a91b5db5a41695fe0357fbdff0d5767 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 3 Mar 2010 14:13:08 -0500 Subject: fix race in d_splice_alias() rehashing the negative placeholder opens a race with d_lookup(); we unhash it almost immediately (by d_move()), but the race window is there. Since d_move() doesn't rely on target being hashed, we don't need that d_rehash() at all. Signed-off-by: Al Viro --- fs/dcache.c | 1 - 1 file changed, 1 deletion(-) (limited to 'fs/dcache.c') diff --git a/fs/dcache.c b/fs/dcache.c index 74da947b160b..f1358e5c3a59 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1222,7 +1222,6 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) BUG_ON(!(new->d_flags & DCACHE_DISCONNECTED)); spin_unlock(&dcache_lock); security_d_instantiate(new, inode); - d_rehash(dentry); d_move(new, dentry); iput(inode); } else { -- cgit v1.2.3