X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;ds=sidebyside;f=fs%2Fdebugfs%2Finode.c;h=d22438ef7674870ad4987b9c2eb11555057e4dc8;hb=3c1596efe167322dae87f8390d36f91ce2d7f936;hp=020da4c605935ce30aa70ef56b08935c18d3b123;hpb=4f36557fbe4ab59feb2783cdb5d049cb8c3f34f3;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 020da4c..d22438e 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -25,14 +25,12 @@ #include #include #include - -#define DEBUGFS_MAGIC 0x64626720 - -/* declared over in file.c */ -extern struct file_operations debugfs_file_operations; +#include +#include static struct vfsmount *debugfs_mount; static int debugfs_mount_count; +static bool debugfs_registered; static struct inode *debugfs_get_inode(struct super_block *sb, int mode, dev_t dev) { @@ -40,9 +38,6 @@ static struct inode *debugfs_get_inode(struct super_block *sb, int mode, dev_t d if (inode) { inode->i_mode = mode; - inode->i_uid = 0; - inode->i_gid = 0; - inode->i_blocks = 0; inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; switch (mode & S_IFMT) { default: @@ -51,11 +46,15 @@ static struct inode *debugfs_get_inode(struct super_block *sb, int mode, dev_t d case S_IFREG: inode->i_fop = &debugfs_file_operations; break; + case S_IFLNK: + inode->i_op = &debugfs_link_operations; + break; case S_IFDIR: inode->i_op = &simple_dir_inode_operations; inode->i_fop = &simple_dir_operations; - /* directory inodes start off with i_nlink == 2 (for "." entry) */ + /* directory inodes start off with i_nlink == 2 + * (for "." entry) */ inc_nlink(inode); break; } @@ -95,6 +94,12 @@ static int debugfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) return res; } +static int debugfs_link(struct inode *dir, struct dentry *dentry, int mode) +{ + mode = (mode & S_IALLUGO) | S_IFLNK; + return debugfs_mknod(dir, dentry, mode, 0); +} + static int debugfs_create(struct inode *dir, struct dentry *dentry, int mode) { int res; @@ -143,7 +148,7 @@ static int debugfs_create_by_name(const char *name, mode_t mode, * block. A pointer to that is in the struct vfsmount that we * have around. */ - if (!parent ) { + if (!parent) { if (debugfs_mount && debugfs_mount->mnt_sb) { parent = debugfs_mount->mnt_sb->s_root; } @@ -157,10 +162,18 @@ static int debugfs_create_by_name(const char *name, mode_t mode, mutex_lock(&parent->d_inode->i_mutex); *dentry = lookup_one_len(name, parent, strlen(name)); if (!IS_ERR(*dentry)) { - if ((mode & S_IFMT) == S_IFDIR) + switch (mode & S_IFMT) { + case S_IFDIR: error = debugfs_mkdir(parent->d_inode, *dentry, mode); - else + break; + case S_IFLNK: + error = debugfs_link(parent->d_inode, *dentry, mode); + break; + default: error = debugfs_create(parent->d_inode, *dentry, mode); + break; + } + dput(*dentry); } else error = PTR_ERR(*dentry); mutex_unlock(&parent->d_inode->i_mutex); @@ -192,9 +205,7 @@ static int debugfs_create_by_name(const char *name, mode_t mode, * you are responsible here.) If an error occurs, %NULL will be returned. * * If debugfs is not enabled in the kernel, the value -%ENODEV will be - * returned. It is not wise to check for this value, but rather, check for - * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling - * code. + * returned. */ struct dentry *debugfs_create_file(const char *name, mode_t mode, struct dentry *parent, void *data, @@ -205,13 +216,15 @@ struct dentry *debugfs_create_file(const char *name, mode_t mode, pr_debug("debugfs: creating file '%s'\n",name); - error = simple_pin_fs(&debug_fs_type, &debugfs_mount, &debugfs_mount_count); + error = simple_pin_fs(&debug_fs_type, &debugfs_mount, + &debugfs_mount_count); if (error) goto exit; error = debugfs_create_by_name(name, mode, parent, &dentry); if (error) { dentry = NULL; + simple_release_fs(&debugfs_mount, &debugfs_mount_count); goto exit; } @@ -242,9 +255,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_file); * you are responsible here.) If an error occurs, %NULL will be returned. * * If debugfs is not enabled in the kernel, the value -%ENODEV will be - * returned. It is not wise to check for this value, but rather, check for - * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling - * code. + * returned. */ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent) { @@ -255,6 +266,72 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent) EXPORT_SYMBOL_GPL(debugfs_create_dir); /** + * debugfs_create_symlink- create a symbolic link in the debugfs filesystem + * @name: a pointer to a string containing the name of the symbolic link to + * create. + * @parent: a pointer to the parent dentry for this symbolic link. This + * should be a directory dentry if set. If this paramater is NULL, + * then the symbolic link will be created in the root of the debugfs + * filesystem. + * @target: a pointer to a string containing the path to the target of the + * symbolic link. + * + * This function creates a symbolic link with the given name in debugfs that + * links to the given target path. + * + * This function will return a pointer to a dentry if it succeeds. This + * pointer must be passed to the debugfs_remove() function when the symbolic + * link is to be removed (no automatic cleanup happens if your module is + * unloaded, you are responsible here.) If an error occurs, %NULL will be + * returned. + * + * If debugfs is not enabled in the kernel, the value -%ENODEV will be + * returned. + */ +struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, + const char *target) +{ + struct dentry *result; + char *link; + + link = kstrdup(target, GFP_KERNEL); + if (!link) + return NULL; + + result = debugfs_create_file(name, S_IFLNK | S_IRWXUGO, parent, link, + NULL); + if (!result) + kfree(link); + return result; +} +EXPORT_SYMBOL_GPL(debugfs_create_symlink); + +static void __debugfs_remove(struct dentry *dentry, struct dentry *parent) +{ + int ret = 0; + + if (debugfs_positive(dentry)) { + if (dentry->d_inode) { + dget(dentry); + switch (dentry->d_inode->i_mode & S_IFMT) { + case S_IFDIR: + ret = simple_rmdir(parent->d_inode, dentry); + break; + case S_IFLNK: + kfree(dentry->d_inode->i_private); + /* fall through */ + default: + simple_unlink(parent->d_inode, dentry); + break; + } + if (!ret) + d_delete(dentry); + dput(dentry); + } + } +} + +/** * debugfs_remove - removes a file or directory from the debugfs filesystem * @dentry: a pointer to a the dentry of the file or directory to be * removed. @@ -279,42 +356,194 @@ void debugfs_remove(struct dentry *dentry) return; mutex_lock(&parent->d_inode->i_mutex); - if (debugfs_positive(dentry)) { - if (dentry->d_inode) { - if (S_ISDIR(dentry->d_inode->i_mode)) - simple_rmdir(parent->d_inode, dentry); - else - simple_unlink(parent->d_inode, dentry); - dput(dentry); + __debugfs_remove(dentry, parent); + mutex_unlock(&parent->d_inode->i_mutex); + simple_release_fs(&debugfs_mount, &debugfs_mount_count); +} +EXPORT_SYMBOL_GPL(debugfs_remove); + +/** + * debugfs_remove_recursive - recursively removes a directory + * @dentry: a pointer to a the dentry of the directory to be removed. + * + * This function recursively removes a directory tree in debugfs that + * was previously created with a call to another debugfs function + * (like debugfs_create_file() or variants thereof.) + * + * This function is required to be called in order for the file to be + * removed, no automatic cleanup of files will happen when a module is + * removed, you are responsible here. + */ +void debugfs_remove_recursive(struct dentry *dentry) +{ + struct dentry *child; + struct dentry *parent; + + if (!dentry) + return; + + parent = dentry->d_parent; + if (!parent || !parent->d_inode) + return; + + parent = dentry; + mutex_lock(&parent->d_inode->i_mutex); + + while (1) { + /* + * When all dentries under "parent" has been removed, + * walk up the tree until we reach our starting point. + */ + if (list_empty(&parent->d_subdirs)) { + mutex_unlock(&parent->d_inode->i_mutex); + if (parent == dentry) + break; + parent = parent->d_parent; + mutex_lock(&parent->d_inode->i_mutex); + } + child = list_entry(parent->d_subdirs.next, struct dentry, + d_u.d_child); + next_sibling: + + /* + * If "child" isn't empty, walk down the tree and + * remove all its descendants first. + */ + if (!list_empty(&child->d_subdirs)) { + mutex_unlock(&parent->d_inode->i_mutex); + parent = child; + mutex_lock(&parent->d_inode->i_mutex); + continue; } + __debugfs_remove(child, parent); + if (parent->d_subdirs.next == &child->d_u.d_child) { + /* + * Try the next sibling. + */ + if (child->d_u.d_child.next != &parent->d_subdirs) { + child = list_entry(child->d_u.d_child.next, + struct dentry, + d_u.d_child); + goto next_sibling; + } + + /* + * Avoid infinite loop if we fail to remove + * one dentry. + */ + mutex_unlock(&parent->d_inode->i_mutex); + break; + } + simple_release_fs(&debugfs_mount, &debugfs_mount_count); } + + parent = dentry->d_parent; + mutex_lock(&parent->d_inode->i_mutex); + __debugfs_remove(dentry, parent); mutex_unlock(&parent->d_inode->i_mutex); simple_release_fs(&debugfs_mount, &debugfs_mount_count); } -EXPORT_SYMBOL_GPL(debugfs_remove); +EXPORT_SYMBOL_GPL(debugfs_remove_recursive); -static decl_subsys(debug, NULL, NULL); +/** + * debugfs_rename - rename a file/directory in the debugfs filesystem + * @old_dir: a pointer to the parent dentry for the renamed object. This + * should be a directory dentry. + * @old_dentry: dentry of an object to be renamed. + * @new_dir: a pointer to the parent dentry where the object should be + * moved. This should be a directory dentry. + * @new_name: a pointer to a string containing the target name. + * + * This function renames a file/directory in debugfs. The target must not + * exist for rename to succeed. + * + * This function will return a pointer to old_dentry (which is updated to + * reflect renaming) if it succeeds. If an error occurs, %NULL will be + * returned. + * + * If debugfs is not enabled in the kernel, the value -%ENODEV will be + * returned. + */ +struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, + struct dentry *new_dir, const char *new_name) +{ + int error; + struct dentry *dentry = NULL, *trap; + const char *old_name; + + trap = lock_rename(new_dir, old_dir); + /* Source or destination directories don't exist? */ + if (!old_dir->d_inode || !new_dir->d_inode) + goto exit; + /* Source does not exist, cyclic rename, or mountpoint? */ + if (!old_dentry->d_inode || old_dentry == trap || + d_mountpoint(old_dentry)) + goto exit; + dentry = lookup_one_len(new_name, new_dir, strlen(new_name)); + /* Lookup failed, cyclic rename or target exists? */ + if (IS_ERR(dentry) || dentry == trap || dentry->d_inode) + goto exit; + + old_name = fsnotify_oldname_init(old_dentry->d_name.name); + + error = simple_rename(old_dir->d_inode, old_dentry, new_dir->d_inode, + dentry); + if (error) { + fsnotify_oldname_free(old_name); + goto exit; + } + d_move(old_dentry, dentry); + fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name, + old_dentry->d_name.name, S_ISDIR(old_dentry->d_inode->i_mode), + NULL, old_dentry); + fsnotify_oldname_free(old_name); + unlock_rename(new_dir, old_dir); + dput(dentry); + return old_dentry; +exit: + if (dentry && !IS_ERR(dentry)) + dput(dentry); + unlock_rename(new_dir, old_dir); + return NULL; +} +EXPORT_SYMBOL_GPL(debugfs_rename); + +/** + * debugfs_initialized - Tells whether debugfs has been registered + */ +bool debugfs_initialized(void) +{ + return debugfs_registered; +} +EXPORT_SYMBOL_GPL(debugfs_initialized); + + +static struct kobject *debug_kobj; static int __init debugfs_init(void) { int retval; - kset_set_kset_s(&debug_subsys, kernel_subsys); - retval = subsystem_register(&debug_subsys); - if (retval) - return retval; + debug_kobj = kobject_create_and_add("debug", kernel_kobj); + if (!debug_kobj) + return -EINVAL; retval = register_filesystem(&debug_fs_type); if (retval) - subsystem_unregister(&debug_subsys); + kobject_put(debug_kobj); + else + debugfs_registered = true; + return retval; } static void __exit debugfs_exit(void) { + debugfs_registered = false; + simple_release_fs(&debugfs_mount, &debugfs_mount_count); unregister_filesystem(&debug_fs_type); - subsystem_unregister(&debug_subsys); + kobject_put(debug_kobj); } core_initcall(debugfs_init);