Merge tag 'configfs-for-5.4' of git://git.infradead.org/users/hch/configfs (c9fe5630) · Commits · 戴 / test

fs/configfs/configfs_internal.h

+5 −16

Original line number	Diff line number	Diff line
		@@ -34,7 +34,7 @@ struct configfs_dirent {
		int s_dependent_count;
		struct list_head s_sibling;
		struct list_head s_children;
		struct list_head s_links;
		int s_links;
		void * s_element;
		int s_type;
		umode_t s_mode;
		@@ -66,7 +66,7 @@ extern struct kmem_cache *configfs_dir_cachep;
		extern int configfs_is_root(struct config_item *item);

		extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent , struct super_block );
		extern int configfs_create(struct dentry , umode_t mode, void (init)(struct inode *));
		extern struct inode configfs_create(struct dentry , umode_t mode);

		extern int configfs_create_file(struct config_item , const struct configfs_attribute );
		extern int configfs_create_bin_file(struct config_item *,
		@@ -84,7 +84,6 @@ extern int configfs_setattr(struct dentry dentry, struct iattr iattr);
		extern struct dentry *configfs_pin_fs(void);
		extern void configfs_release_fs(void);

		extern struct rw_semaphore configfs_rename_sem;
		extern const struct file_operations configfs_dir_operations;
		extern const struct file_operations configfs_file_operations;
		extern const struct file_operations configfs_bin_file_operations;
		@@ -97,14 +96,8 @@ extern int configfs_symlink(struct inode dir, struct dentry dentry,
		const char *symname);
		extern int configfs_unlink(struct inode dir, struct dentry dentry);

		struct configfs_symlink {
		struct list_head sl_list;
		struct config_item *sl_target;
		};

		extern int configfs_create_link(struct configfs_symlink *sl,
		struct dentry *parent,
		struct dentry *dentry);
		int configfs_create_link(struct configfs_dirent target, struct dentry parent,
		struct dentry dentry, char body);

		static inline struct config_item * to_item(struct dentry * dentry)
		{
		@@ -132,10 +125,6 @@ static inline struct config_item configfs_get_config_item(struct dentry dentry
		spin_lock(&dentry->d_lock);
		if (!d_unhashed(dentry)) {
		struct configfs_dirent * sd = dentry->d_fsdata;
		if (sd->s_type & CONFIGFS_ITEM_LINK) {
		struct configfs_symlink * sl = sd->s_element;
		item = config_item_get(sl->sl_target);
		} else
		item = config_item_get(sd->s_element);
		}
		spin_unlock(&dentry->d_lock);

fs/configfs/dir.c

+65 −108

Original line number	Diff line number	Diff line
		@@ -22,7 +22,6 @@
		#include <linux/configfs.h>
		#include "configfs_internal.h"

		DECLARE_RWSEM(configfs_rename_sem);
		/*
		* Protects mutations of configfs_dirent linkage together with proper i_mutex
		* Also protects mutations of symlinks linkage to target configfs_dirent
		@@ -191,7 +190,6 @@ static struct configfs_dirent configfs_new_dirent(struct configfs_dirent paren
		return ERR_PTR(-ENOMEM);

		atomic_set(&sd->s_count, 1);
		INIT_LIST_HEAD(&sd->s_links);
		INIT_LIST_HEAD(&sd->s_children);
		sd->s_element = element;
		sd->s_type = type;
		@@ -253,30 +251,16 @@ int configfs_make_dirent(struct configfs_dirent * parent_sd,
		return 0;
		}

		static void init_dir(struct inode * inode)
		static void configfs_remove_dirent(struct dentry *dentry)
		{
		inode->i_op = &configfs_dir_inode_operations;
		inode->i_fop = &configfs_dir_operations;

		/* directory inodes start off with i_nlink == 2 (for "." entry) */
		inc_nlink(inode);
		}

		static void configfs_init_file(struct inode * inode)
		{
		inode->i_size = PAGE_SIZE;
		inode->i_fop = &configfs_file_operations;
		}

		static void configfs_init_bin_file(struct inode *inode)
		{
		inode->i_size = 0;
		inode->i_fop = &configfs_bin_file_operations;
		}
		struct configfs_dirent *sd = dentry->d_fsdata;

		static void init_symlink(struct inode * inode)
		{
		inode->i_op = &configfs_symlink_inode_operations;
		if (!sd)
		return;
		spin_lock(&configfs_dirent_lock);
		list_del_init(&sd->s_sibling);
		spin_unlock(&configfs_dirent_lock);
		configfs_put(sd);
		}

		/**
		@@ -294,6 +278,7 @@ static int configfs_create_dir(struct config_item item, struct dentry dentry,
		int error;
		umode_t mode = S_IFDIR\| S_IRWXU \| S_IRUGO \| S_IXUGO;
		struct dentry *p = dentry->d_parent;
		struct inode *inode;

		BUG_ON(!item);

		@@ -308,20 +293,24 @@ static int configfs_create_dir(struct config_item item, struct dentry dentry,
		return error;

		configfs_set_dir_dirent_depth(p->d_fsdata, dentry->d_fsdata);
		error = configfs_create(dentry, mode, init_dir);
		if (!error) {
		inode = configfs_create(dentry, mode);
		if (IS_ERR(inode))
		goto out_remove;

		inode->i_op = &configfs_dir_inode_operations;
		inode->i_fop = &configfs_dir_operations;
		/* directory inodes start off with i_nlink == 2 (for "." entry) */
		inc_nlink(inode);
		d_instantiate(dentry, inode);
		/* already hashed */
		dget(dentry); /* pin directory dentries in core */
		inc_nlink(d_inode(p));
		item->ci_dentry = dentry;
		} else {
		struct configfs_dirent *sd = dentry->d_fsdata;
		if (sd) {
		spin_lock(&configfs_dirent_lock);
		list_del_init(&sd->s_sibling);
		spin_unlock(&configfs_dirent_lock);
		configfs_put(sd);
		}
		}
		return error;
		return 0;

		out_remove:
		configfs_remove_dirent(dentry);
		return PTR_ERR(inode);
		}

		/*
		@@ -362,41 +351,40 @@ int configfs_dirent_is_ready(struct configfs_dirent *sd)
		return ret;
		}

		int configfs_create_link(struct configfs_symlink *sl,
		struct dentry *parent,
		struct dentry *dentry)
		int configfs_create_link(struct configfs_dirent target, struct dentry parent,
		struct dentry dentry, char body)
		{
		int err = 0;
		umode_t mode = S_IFLNK \| S_IRWXUGO;
		struct configfs_dirent *p = parent->d_fsdata;
		struct inode *inode;

		err = configfs_make_dirent(p, dentry, sl, mode,
		CONFIGFS_ITEM_LINK, p->s_frag);
		if (!err) {
		err = configfs_create(dentry, mode, init_symlink);
		if (err) {
		struct configfs_dirent *sd = dentry->d_fsdata;
		if (sd) {
		spin_lock(&configfs_dirent_lock);
		list_del_init(&sd->s_sibling);
		spin_unlock(&configfs_dirent_lock);
		configfs_put(sd);
		}
		}
		}
		err = configfs_make_dirent(p, dentry, target, mode, CONFIGFS_ITEM_LINK,
		p->s_frag);
		if (err)
		return err;

		inode = configfs_create(dentry, mode);
		if (IS_ERR(inode))
		goto out_remove;

		inode->i_link = body;
		inode->i_op = &configfs_symlink_inode_operations;
		d_instantiate(dentry, inode);
		dget(dentry); /* pin link dentries in core */
		return 0;

		out_remove:
		configfs_remove_dirent(dentry);
		return PTR_ERR(inode);
		}

		static void remove_dir(struct dentry * d)
		{
		struct dentry * parent = dget(d->d_parent);
		struct configfs_dirent * sd;

		sd = d->d_fsdata;
		spin_lock(&configfs_dirent_lock);
		list_del_init(&sd->s_sibling);
		spin_unlock(&configfs_dirent_lock);
		configfs_put(sd);
		configfs_remove_dirent(d);

		if (d_really_is_positive(d))
		simple_rmdir(d_inode(parent),d);

		@@ -437,20 +425,27 @@ static void configfs_remove_dir(struct config_item * item)
		static int configfs_attach_attr(struct configfs_dirent * sd, struct dentry * dentry)
		{
		struct configfs_attribute * attr = sd->s_element;
		int error;
		struct inode *inode;

		spin_lock(&configfs_dirent_lock);
		dentry->d_fsdata = configfs_get(sd);
		sd->s_dentry = dentry;
		spin_unlock(&configfs_dirent_lock);

		error = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) \| S_IFREG,
		(sd->s_type & CONFIGFS_ITEM_BIN_ATTR) ?
		configfs_init_bin_file :
		configfs_init_file);
		if (error)
		inode = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) \| S_IFREG);
		if (IS_ERR(inode)) {
		configfs_put(sd);
		return error;
		return PTR_ERR(inode);
		}
		if (sd->s_type & CONFIGFS_ITEM_BIN_ATTR) {
		inode->i_size = 0;
		inode->i_fop = &configfs_bin_file_operations;
		} else {
		inode->i_size = PAGE_SIZE;
		inode->i_fop = &configfs_file_operations;
		}
		d_add(dentry, inode);
		return 0;
		}

		static struct dentry * configfs_lookup(struct inode *dir,
		@@ -520,7 +515,7 @@ static int configfs_detach_prep(struct dentry dentry, struct dentry *wait)
		parent_sd->s_type \|= CONFIGFS_USET_DROPPING;

		ret = -EBUSY;
		if (!list_empty(&parent_sd->s_links))
		if (parent_sd->s_links)
		goto out;

		ret = 0;
		@@ -1578,44 +1573,6 @@ const struct inode_operations configfs_root_inode_operations = {
		.setattr = configfs_setattr,
		};

		#if 0
		int configfs_rename_dir(struct config_item * item, const char *new_name)
		{
		int error = 0;
		struct dentry * new_dentry, * parent;

		if (!strcmp(config_item_name(item), new_name))
		return -EINVAL;

		if (!item->parent)
		return -EINVAL;

		down_write(&configfs_rename_sem);
		parent = item->parent->dentry;

		inode_lock(d_inode(parent));

		new_dentry = lookup_one_len(new_name, parent, strlen(new_name));
		if (!IS_ERR(new_dentry)) {
		if (d_really_is_negative(new_dentry)) {
		error = config_item_set_name(item, "%s", new_name);
		if (!error) {
		d_add(new_dentry, NULL);
		d_move(item->dentry, new_dentry);
		}
		else
		d_delete(new_dentry);
		} else
		error = -EEXIST;
		dput(new_dentry);
		}
		inode_unlock(d_inode(parent));
		up_write(&configfs_rename_sem);

		return error;
		}
		#endif

		static int configfs_dir_open(struct inode inode, struct file file)
		{
		struct dentry * dentry = file->f_path.dentry;

fs/configfs/inode.c

+5 −19

Original line number	Diff line number	Diff line
		@@ -164,41 +164,27 @@ static void configfs_set_inode_lock_class(struct configfs_dirent *sd,

		#endif /* CONFIG_LOCKDEP */

		int configfs_create(struct dentry * dentry, umode_t mode, void (init)(struct inode ))
		struct inode configfs_create(struct dentry dentry, umode_t mode)
		{
		int error = 0;
		struct inode *inode = NULL;
		struct configfs_dirent *sd;
		struct inode *p_inode;

		if (!dentry)
		return -ENOENT;
		return ERR_PTR(-ENOENT);

		if (d_really_is_positive(dentry))
		return -EEXIST;
		return ERR_PTR(-EEXIST);

		sd = dentry->d_fsdata;
		inode = configfs_new_inode(mode, sd, dentry->d_sb);
		if (!inode)
		return -ENOMEM;
		return ERR_PTR(-ENOMEM);

		p_inode = d_inode(dentry->d_parent);
		p_inode->i_mtime = p_inode->i_ctime = current_time(p_inode);
		configfs_set_inode_lock_class(sd, inode);

		init(inode);
		if (S_ISDIR(mode) \|\| S_ISLNK(mode)) {
		/*
		* ->symlink(), ->mkdir(), configfs_register_subsystem() or
		* create_default_group() - already hashed.
		*/
		d_instantiate(dentry, inode);
		dget(dentry); /* pin link and directory dentries in core */
		} else {
		/* ->lookup() */
		d_add(dentry, inode);
		}
		return error;
		return inode;
		}

		/*

fs/configfs/mount.c

+9 −0

Original line number	Diff line number	Diff line
		@@ -28,9 +28,18 @@ static struct vfsmount *configfs_mount = NULL;
		struct kmem_cache *configfs_dir_cachep;
		static int configfs_mnt_count = 0;


		static void configfs_free_inode(struct inode *inode)
		{
		if (S_ISLNK(inode->i_mode))
		kfree(inode->i_link);
		free_inode_nonrcu(inode);
		}

		static const struct super_operations configfs_ops = {
		.statfs = simple_statfs,
		.drop_inode = generic_delete_inode,
		.free_inode = configfs_free_inode,
		};

		static struct config_group configfs_root_group = {

fs/configfs/symlink.c

+86 −111

Original line number	Diff line number	Diff line
		@@ -55,41 +55,63 @@ static void fill_item_path(struct config_item * item, char * buffer, int length)
		}
		}

		static int configfs_get_target_path(struct config_item *item,
		struct config_item target, char path)
		{
		int depth, size;
		char *s;

		depth = item_depth(item);
		size = item_path_length(target) + depth * 3 - 1;
		if (size > PATH_MAX)
		return -ENAMETOOLONG;

		pr_debug("%s: depth = %d, size = %d\n", __func__, depth, size);

		for (s = path; depth--; s += 3)
		strcpy(s,"../");

		fill_item_path(target, path, size);
		pr_debug("%s: path = '%s'\n", __func__, path);
		return 0;
		}

		static int create_link(struct config_item *parent_item,
		struct config_item *item,
		struct dentry *dentry)
		{
		struct configfs_dirent *target_sd = item->ci_dentry->d_fsdata;
		struct configfs_symlink *sl;
		char *body;
		int ret;

		ret = -ENOENT;
		if (!configfs_dirent_is_ready(target_sd))
		goto out;
		ret = -ENOMEM;
		sl = kmalloc(sizeof(struct configfs_symlink), GFP_KERNEL);
		if (sl) {
		return -ENOENT;

		body = kzalloc(PAGE_SIZE, GFP_KERNEL);
		if (!body)
		return -ENOMEM;

		configfs_get(target_sd);
		spin_lock(&configfs_dirent_lock);
		if (target_sd->s_type & CONFIGFS_USET_DROPPING) {
		spin_unlock(&configfs_dirent_lock);
		kfree(sl);
		configfs_put(target_sd);
		kfree(body);
		return -ENOENT;
		}
		sl->sl_target = config_item_get(item);
		list_add(&sl->sl_list, &target_sd->s_links);
		target_sd->s_links++;
		spin_unlock(&configfs_dirent_lock);
		ret = configfs_create_link(sl, parent_item->ci_dentry,
		dentry);
		ret = configfs_get_target_path(item, item, body);
		if (!ret)
		ret = configfs_create_link(target_sd, parent_item->ci_dentry,
		dentry, body);
		if (ret) {
		spin_lock(&configfs_dirent_lock);
		list_del_init(&sl->sl_list);
		target_sd->s_links--;
		spin_unlock(&configfs_dirent_lock);
		config_item_put(item);
		kfree(sl);
		}
		configfs_put(target_sd);
		kfree(body);
		}

		out:
		return ret;
		}

		@@ -131,9 +153,8 @@ int configfs_symlink(struct inode dir, struct dentry dentry, const char *symna
		* Fake invisibility if dir belongs to a group/default groups hierarchy
		* being attached
		*/
		ret = -ENOENT;
		if (!configfs_dirent_is_ready(sd))
		goto out;
		return -ENOENT;

		parent_item = configfs_get_config_item(dentry->d_parent);
		type = parent_item->ci_type;
		@@ -143,10 +164,41 @@ int configfs_symlink(struct inode dir, struct dentry dentry, const char *symna
		!type->ct_item_ops->allow_link)
		goto out_put;

		/*
		* This is really sick. What they wanted was a hybrid of
		* link(2) and symlink(2) - they wanted the target resolved
		* at syscall time (as link(2) would've done), be a directory
		* (which link(2) would've refused to do) AND be a deep
		* fucking magic, making the target busy from rmdir POV.
		* symlink(2) is nothing of that sort, and the locking it
		* gets matches the normal symlink(2) semantics. Without
		* attempts to resolve the target (which might very well
		* not even exist yet) done prior to locking the parent
		* directory. This perversion, OTOH, needs to resolve
		* the target, which would lead to obvious deadlocks if
		* attempted with any directories locked.
		*
		* Unfortunately, that garbage is userland ABI and we should've
		* said "no" back in 2005. Too late now, so we get to
		* play very ugly games with locking.
		*
		* Try ANYTHING of that sort in new code, and you will
		* really regret it. Just ask yourself - what could a BOFH
		* do to me and do I want to find it out first-hand?
		*
		* AV, a thoroughly annoyed bastard.
		*/
		inode_unlock(dir);
		ret = get_target(symname, &path, &target_item, dentry->d_sb);
		inode_lock(dir);
		if (ret)
		goto out_put;

		if (dentry->d_inode \|\| d_unhashed(dentry))
		ret = -EEXIST;
		else
		ret = inode_permission(dir, MAY_WRITE \| MAY_EXEC);
		if (!ret)
		ret = type->ct_item_ops->allow_link(parent_item, target_item);
		if (!ret) {
		mutex_lock(&configfs_symlink_mutex);
		@@ -162,15 +214,12 @@ int configfs_symlink(struct inode dir, struct dentry dentry, const char *symna

		out_put:
		config_item_put(parent_item);

		out:
		return ret;
		}

		int configfs_unlink(struct inode dir, struct dentry dentry)
		{
		struct configfs_dirent *sd = dentry->d_fsdata;
		struct configfs_symlink *sl;
		struct configfs_dirent sd = dentry->d_fsdata, target_sd;
		struct config_item *parent_item;
		const struct config_item_type *type;
		int ret;
		@@ -179,7 +228,7 @@ int configfs_unlink(struct inode dir, struct dentry dentry)
		if (!(sd->s_type & CONFIGFS_ITEM_LINK))
		goto out;

		sl = sd->s_element;
		target_sd = sd->s_element;

		parent_item = configfs_get_config_item(dentry->d_parent);
		type = parent_item->ci_type;
		@@ -193,21 +242,18 @@ int configfs_unlink(struct inode dir, struct dentry dentry)

		/*
		* drop_link() must be called before
		* list_del_init(&sl->sl_list), so that the order of
		* decrementing target's ->s_links, so that the order of
		* drop_link(this, target) and drop_item(target) is preserved.
		*/
		if (type && type->ct_item_ops &&
		type->ct_item_ops->drop_link)
		type->ct_item_ops->drop_link(parent_item,
		sl->sl_target);
		target_sd->s_element);

		spin_lock(&configfs_dirent_lock);
		list_del_init(&sl->sl_list);
		target_sd->s_links--;
		spin_unlock(&configfs_dirent_lock);

		/* Put reference from create_link() */
		config_item_put(sl->sl_target);
		kfree(sl);
		configfs_put(target_sd);

		config_item_put(parent_item);

		@@ -217,79 +263,8 @@ out:
		return ret;
		}

		static int configfs_get_target_path(struct config_item * item, struct config_item * target,
		char *path)
		{
		char * s;
		int depth, size;

		depth = item_depth(item);
		size = item_path_length(target) + depth * 3 - 1;
		if (size > PATH_MAX)
		return -ENAMETOOLONG;

		pr_debug("%s: depth = %d, size = %d\n", __func__, depth, size);

		for (s = path; depth--; s += 3)
		strcpy(s,"../");

		fill_item_path(target, path, size);
		pr_debug("%s: path = '%s'\n", __func__, path);

		return 0;
		}

		static int configfs_getlink(struct dentry dentry, char path)
		{
		struct config_item item, target_item;
		int error = 0;

		item = configfs_get_config_item(dentry->d_parent);
		if (!item)
		return -EINVAL;

		target_item = configfs_get_config_item(dentry);
		if (!target_item) {
		config_item_put(item);
		return -EINVAL;
		}

		down_read(&configfs_rename_sem);
		error = configfs_get_target_path(item, target_item, path);
		up_read(&configfs_rename_sem);

		config_item_put(item);
		config_item_put(target_item);
		return error;

		}

		static const char configfs_get_link(struct dentry dentry,
		struct inode *inode,
		struct delayed_call *done)
		{
		char *body;
		int error;

		if (!dentry)
		return ERR_PTR(-ECHILD);

		body = kzalloc(PAGE_SIZE, GFP_KERNEL);
		if (!body)
		return ERR_PTR(-ENOMEM);

		error = configfs_getlink(dentry, body);
		if (!error) {
		set_delayed_call(done, kfree_link, body);
		return body;
		}

		kfree(body);
		return ERR_PTR(error);
		}

		const struct inode_operations configfs_symlink_inode_operations = {
		.get_link = configfs_get_link,
		.get_link = simple_get_link,
		.setattr = configfs_setattr,
		};

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