fs/exofs/namei.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (C) 2005, 2006
  * Avishay Traeger (avishay@gmail.com)
  * Copyright (C) 2008, 2009
  * Boaz Harrosh <bharrosh@panasas.com>
  *
  * Copyrights for code taken from ext2:
  *     Copyright (C) 1992, 1993, 1994, 1995
  *     Remy Card (card@masi.ibp.fr)
  *     Laboratoire MASI - Institut Blaise Pascal
  *     Universite Pierre et Marie Curie (Paris VI)
  *     from
  *     linux/fs/minix/inode.c
  *     Copyright (C) 1991, 1992  Linus Torvalds
  *
  * This file is part of exofs.
  *
  * exofs is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation.  Since it is based on ext2, and the only
  * valid version of GPL for the Linux kernel is version 2, the only valid
  * version of GPL for exofs is version 2.
  *
  * exofs is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with exofs; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */

 #include "exofs.h"

 static inline int exofs_add_nondir(struct dentry *dentry, struct inode *inode)
 {
 	int err = exofs_add_link(dentry, inode);
 	if (!err) {
 		d_instantiate(dentry, inode);
 		return 0;
 	}
 	inode_dec_link_count(inode);
 	iput(inode);
 	return err;
 }

 static struct dentry *exofs_lookup(struct inode *dir, struct dentry *dentry,
 				   struct nameidata *nd)
 {
 	struct inode *inode;
 	ino_t ino;

 	if (dentry->d_name.len > EXOFS_NAME_LEN)
 		return ERR_PTR(-ENAMETOOLONG);

 	ino = exofs_inode_by_name(dir, dentry);
 	inode = ino ? exofs_iget(dir->i_sb, ino) : NULL;
 	return d_splice_alias(inode, dentry);
 }

 static int exofs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 			 struct nameidata *nd)
 {
 	struct inode *inode = exofs_new_inode(dir, mode);
 	int err = PTR_ERR(inode);
 	if (!IS_ERR(inode)) {
 		inode->i_op = &exofs_file_inode_operations;
 		inode->i_fop = &exofs_file_operations;
 		inode->i_mapping->a_ops = &exofs_aops;
 		mark_inode_dirty(inode);
 		err = exofs_add_nondir(dentry, inode);
 	}
 	return err;
 }

 static int exofs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 		       dev_t rdev)
 {
 	struct inode *inode;
 	int err;

 	if (!new_valid_dev(rdev))
 		return -EINVAL;

 	inode = exofs_new_inode(dir, mode);
 	err = PTR_ERR(inode);
 	if (!IS_ERR(inode)) {
 		init_special_inode(inode, inode->i_mode, rdev);
 		mark_inode_dirty(inode);
 		err = exofs_add_nondir(dentry, inode);
 	}
 	return err;
 }

 static int exofs_symlink(struct inode *dir, struct dentry *dentry,
 			  const char *symname)
 {
 	struct super_block *sb = dir->i_sb;
 	int err = -ENAMETOOLONG;
 	unsigned l = strlen(symname)+1;
 	struct inode *inode;
 	struct exofs_i_info *oi;

 	if (l > sb->s_blocksize)
 		goto out;

 	inode = exofs_new_inode(dir, S_IFLNK | S_IRWXUGO);
 	err = PTR_ERR(inode);
 	if (IS_ERR(inode))
 		goto out;

 	oi = exofs_i(inode);
 	if (l > sizeof(oi->i_data)) {
 		/* slow symlink */
 		inode->i_op = &exofs_symlink_inode_operations;
 		inode->i_mapping->a_ops = &exofs_aops;
 		memset(oi->i_data, 0, sizeof(oi->i_data));

 		err = page_symlink(inode, symname, l);
 		if (err)
 			goto out_fail;
 	} else {
 		/* fast symlink */
 		inode->i_op = &exofs_fast_symlink_inode_operations;
 		memcpy(oi->i_data, symname, l);
 		inode->i_size = l-1;
 	}
 	mark_inode_dirty(inode);

 	err = exofs_add_nondir(dentry, inode);
 out:
 	return err;

 out_fail:
 	inode_dec_link_count(inode);
 	iput(inode);
 	goto out;
 }

 static int exofs_link(struct dentry *old_dentry, struct inode *dir,
 		struct dentry *dentry)
 {
 	struct inode *inode = old_dentry->d_inode;

 	if (inode->i_nlink >= EXOFS_LINK_MAX)
 		return -EMLINK;

 	inode->i_ctime = CURRENT_TIME;
 	inode_inc_link_count(inode);
 	ihold(inode);

 	return exofs_add_nondir(dentry, inode);
 }

 static int exofs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode;
 	int err = -EMLINK;

 	if (dir->i_nlink >= EXOFS_LINK_MAX)
 		goto out;

 	inode_inc_link_count(dir);

 	inode = exofs_new_inode(dir, S_IFDIR | mode);
 	err = PTR_ERR(inode);
 	if (IS_ERR(inode))
 		goto out_dir;

 	inode->i_op = &exofs_dir_inode_operations;
 	inode->i_fop = &exofs_dir_operations;
 	inode->i_mapping->a_ops = &exofs_aops;

 	inode_inc_link_count(inode);

 	err = exofs_make_empty(inode, dir);
 	if (err)
 		goto out_fail;

 	err = exofs_add_link(dentry, inode);
 	if (err)
 		goto out_fail;

 	d_instantiate(dentry, inode);
 out:
 	return err;

 out_fail:
 	inode_dec_link_count(inode);
 	inode_dec_link_count(inode);
 	iput(inode);
 out_dir:
 	inode_dec_link_count(dir);
 	goto out;
 }

 static int exofs_unlink(struct inode *dir, struct dentry *dentry)
 {
 	struct inode *inode = dentry->d_inode;
 	struct exofs_dir_entry *de;
 	struct page *page;
 	int err = -ENOENT;

 	de = exofs_find_entry(dir, dentry, &page);
 	if (!de)
 		goto out;

 	err = exofs_delete_entry(de, page);
 	if (err)
 		goto out;

 	inode->i_ctime = dir->i_ctime;
 	inode_dec_link_count(inode);
 	err = 0;
 out:
 	return err;
 }

 static int exofs_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	struct inode *inode = dentry->d_inode;
 	int err = -ENOTEMPTY;

 	if (exofs_empty_dir(inode)) {
 		err = exofs_unlink(dir, dentry);
 		if (!err) {
 			inode->i_size = 0;
 			inode_dec_link_count(inode);
 			inode_dec_link_count(dir);
 		}
 	}
 	return err;
 }

 static int exofs_rename(struct inode *old_dir, struct dentry *old_dentry,
 		struct inode *new_dir, struct dentry *new_dentry)
 {
 	struct inode *old_inode = old_dentry->d_inode;
 	struct inode *new_inode = new_dentry->d_inode;
 	struct page *dir_page = NULL;
 	struct exofs_dir_entry *dir_de = NULL;
 	struct page *old_page;
 	struct exofs_dir_entry *old_de;
 	int err = -ENOENT;

 	old_de = exofs_find_entry(old_dir, old_dentry, &old_page);
 	if (!old_de)
 		goto out;

 	if (S_ISDIR(old_inode->i_mode)) {
 		err = -EIO;
 		dir_de = exofs_dotdot(old_inode, &dir_page);
 		if (!dir_de)
 			goto out_old;
 	}

 	if (new_inode) {
 		struct page *new_page;
 		struct exofs_dir_entry *new_de;

 		err = -ENOTEMPTY;
 		if (dir_de && !exofs_empty_dir(new_inode))
 			goto out_dir;

 		err = -ENOENT;
 		new_de = exofs_find_entry(new_dir, new_dentry, &new_page);
 		if (!new_de)
 			goto out_dir;
 		err = exofs_set_link(new_dir, new_de, new_page, old_inode);
 		new_inode->i_ctime = CURRENT_TIME;
 		if (dir_de)
 			drop_nlink(new_inode);
 		inode_dec_link_count(new_inode);
 		if (err)
 			goto out_dir;
 	} else {
 		if (dir_de) {
 			err = -EMLINK;
 			if (new_dir->i_nlink >= EXOFS_LINK_MAX)
 				goto out_dir;
 		}
 		err = exofs_add_link(new_dentry, old_inode);
 		if (err)
 			goto out_dir;
 		if (dir_de)
 			inode_inc_link_count(new_dir);
 	}

 	old_inode->i_ctime = CURRENT_TIME;

 	exofs_delete_entry(old_de, old_page);
 	mark_inode_dirty(old_inode);

 	if (dir_de) {
 		err = exofs_set_link(old_inode, dir_de, dir_page, new_dir);
 		inode_dec_link_count(old_dir);
 		if (err)
 			goto out_dir;
 	}
 	return 0;


 out_dir:
 	if (dir_de) {
 		kunmap(dir_page);
 		page_cache_release(dir_page);
 	}
 out_old:
 	kunmap(old_page);
 	page_cache_release(old_page);
 out:
 	return err;
 }

 const struct inode_operations exofs_dir_inode_operations = {
 	.create 	= exofs_create,
 	.lookup 	= exofs_lookup,
 	.link   	= exofs_link,
 	.unlink 	= exofs_unlink,
 	.symlink	= exofs_symlink,
 	.mkdir  	= exofs_mkdir,
 	.rmdir  	= exofs_rmdir,
 	.mknod  	= exofs_mknod,
 	.rename 	= exofs_rename,
 	.setattr	= exofs_setattr,
 };

 const struct inode_operations exofs_special_inode_operations = {
 	.setattr	= exofs_setattr,
 };
	/*
	* Copyright (C) 2005, 2006
	* Avishay Traeger (avishay@gmail.com)
	* Copyright (C) 2008, 2009
	* Boaz Harrosh <bharrosh@panasas.com>
	*
	* Copyrights for code taken from ext2:
	* Copyright (C) 1992, 1993, 1994, 1995
	* Remy Card (card@masi.ibp.fr)
	* Laboratoire MASI - Institut Blaise Pascal
	* Universite Pierre et Marie Curie (Paris VI)
	* from
	* linux/fs/minix/inode.c
	* Copyright (C) 1991, 1992 Linus Torvalds
	*
	* This file is part of exofs.
	*
	* exofs is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation. Since it is based on ext2, and the only
	* valid version of GPL for the Linux kernel is version 2, the only valid
	* version of GPL for exofs is version 2.
	*
	* exofs is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with exofs; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	#include "exofs.h"

	static inline int exofs_add_nondir(struct dentry dentry, struct inode inode)
	{
	int err = exofs_add_link(dentry, inode);
	if (!err) {
	d_instantiate(dentry, inode);
	return 0;
	}
	inode_dec_link_count(inode);
	iput(inode);
	return err;
	}

	static struct dentry exofs_lookup(struct inode dir, struct dentry *dentry,
	struct nameidata *nd)
	{
	struct inode *inode;
	ino_t ino;

	if (dentry->d_name.len > EXOFS_NAME_LEN)
	return ERR_PTR(-ENAMETOOLONG);

	ino = exofs_inode_by_name(dir, dentry);
	inode = ino ? exofs_iget(dir->i_sb, ino) : NULL;
	return d_splice_alias(inode, dentry);
	}

	static int exofs_create(struct inode dir, struct dentry dentry, umode_t mode,
	struct nameidata *nd)
	{
	struct inode *inode = exofs_new_inode(dir, mode);
	int err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
	inode->i_op = &exofs_file_inode_operations;
	inode->i_fop = &exofs_file_operations;
	inode->i_mapping->a_ops = &exofs_aops;
	mark_inode_dirty(inode);
	err = exofs_add_nondir(dentry, inode);
	}
	return err;
	}

	static int exofs_mknod(struct inode dir, struct dentry dentry, umode_t mode,
	dev_t rdev)
	{
	struct inode *inode;
	int err;

	if (!new_valid_dev(rdev))
	return -EINVAL;

	inode = exofs_new_inode(dir, mode);
	err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
	init_special_inode(inode, inode->i_mode, rdev);
	mark_inode_dirty(inode);
	err = exofs_add_nondir(dentry, inode);
	}
	return err;
	}

	static int exofs_symlink(struct inode dir, struct dentry dentry,
	const char *symname)
	{
	struct super_block *sb = dir->i_sb;
	int err = -ENAMETOOLONG;
	unsigned l = strlen(symname)+1;
	struct inode *inode;
	struct exofs_i_info *oi;

	if (l > sb->s_blocksize)
	goto out;

	inode = exofs_new_inode(dir, S_IFLNK \| S_IRWXUGO);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
	goto out;

	oi = exofs_i(inode);
	if (l > sizeof(oi->i_data)) {
	/* slow symlink */
	inode->i_op = &exofs_symlink_inode_operations;
	inode->i_mapping->a_ops = &exofs_aops;
	memset(oi->i_data, 0, sizeof(oi->i_data));

	err = page_symlink(inode, symname, l);
	if (err)
	goto out_fail;
	} else {
	/* fast symlink */
	inode->i_op = &exofs_fast_symlink_inode_operations;
	memcpy(oi->i_data, symname, l);
	inode->i_size = l-1;
	}
	mark_inode_dirty(inode);

	err = exofs_add_nondir(dentry, inode);
	out:
	return err;

	out_fail:
	inode_dec_link_count(inode);
	iput(inode);
	goto out;
	}

	static int exofs_link(struct dentry old_dentry, struct inode dir,
	struct dentry *dentry)
	{
	struct inode *inode = old_dentry->d_inode;

	if (inode->i_nlink >= EXOFS_LINK_MAX)
	return -EMLINK;

	inode->i_ctime = CURRENT_TIME;
	inode_inc_link_count(inode);
	ihold(inode);

	return exofs_add_nondir(dentry, inode);
	}

	static int exofs_mkdir(struct inode dir, struct dentry dentry, umode_t mode)
	{
	struct inode *inode;
	int err = -EMLINK;

	if (dir->i_nlink >= EXOFS_LINK_MAX)
	goto out;

	inode_inc_link_count(dir);

	inode = exofs_new_inode(dir, S_IFDIR \| mode);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
	goto out_dir;

	inode->i_op = &exofs_dir_inode_operations;
	inode->i_fop = &exofs_dir_operations;
	inode->i_mapping->a_ops = &exofs_aops;

	inode_inc_link_count(inode);

	err = exofs_make_empty(inode, dir);
	if (err)
	goto out_fail;

	err = exofs_add_link(dentry, inode);
	if (err)
	goto out_fail;

	d_instantiate(dentry, inode);
	out:
	return err;

	out_fail:
	inode_dec_link_count(inode);
	inode_dec_link_count(inode);
	iput(inode);
	out_dir:
	inode_dec_link_count(dir);
	goto out;
	}

	static int exofs_unlink(struct inode dir, struct dentry dentry)
	{
	struct inode *inode = dentry->d_inode;
	struct exofs_dir_entry *de;
	struct page *page;
	int err = -ENOENT;

	de = exofs_find_entry(dir, dentry, &page);
	if (!de)
	goto out;

	err = exofs_delete_entry(de, page);
	if (err)
	goto out;

	inode->i_ctime = dir->i_ctime;
	inode_dec_link_count(inode);
	err = 0;
	out:
	return err;
	}

	static int exofs_rmdir(struct inode dir, struct dentry dentry)
	{
	struct inode *inode = dentry->d_inode;
	int err = -ENOTEMPTY;

	if (exofs_empty_dir(inode)) {
	err = exofs_unlink(dir, dentry);
	if (!err) {
	inode->i_size = 0;
	inode_dec_link_count(inode);
	inode_dec_link_count(dir);
	}
	}
	return err;
	}

	static int exofs_rename(struct inode old_dir, struct dentry old_dentry,
	struct inode new_dir, struct dentry new_dentry)
	{
	struct inode *old_inode = old_dentry->d_inode;
	struct inode *new_inode = new_dentry->d_inode;
	struct page *dir_page = NULL;
	struct exofs_dir_entry *dir_de = NULL;
	struct page *old_page;
	struct exofs_dir_entry *old_de;
	int err = -ENOENT;

	old_de = exofs_find_entry(old_dir, old_dentry, &old_page);
	if (!old_de)
	goto out;

	if (S_ISDIR(old_inode->i_mode)) {
	err = -EIO;
	dir_de = exofs_dotdot(old_inode, &dir_page);
	if (!dir_de)
	goto out_old;
	}

	if (new_inode) {
	struct page *new_page;
	struct exofs_dir_entry *new_de;

	err = -ENOTEMPTY;
	if (dir_de && !exofs_empty_dir(new_inode))
	goto out_dir;

	err = -ENOENT;
	new_de = exofs_find_entry(new_dir, new_dentry, &new_page);
	if (!new_de)
	goto out_dir;
	err = exofs_set_link(new_dir, new_de, new_page, old_inode);
	new_inode->i_ctime = CURRENT_TIME;
	if (dir_de)
	drop_nlink(new_inode);
	inode_dec_link_count(new_inode);
	if (err)
	goto out_dir;
	} else {
	if (dir_de) {
	err = -EMLINK;
	if (new_dir->i_nlink >= EXOFS_LINK_MAX)
	goto out_dir;
	}
	err = exofs_add_link(new_dentry, old_inode);
	if (err)
	goto out_dir;
	if (dir_de)
	inode_inc_link_count(new_dir);
	}

	old_inode->i_ctime = CURRENT_TIME;

	exofs_delete_entry(old_de, old_page);
	mark_inode_dirty(old_inode);

	if (dir_de) {
	err = exofs_set_link(old_inode, dir_de, dir_page, new_dir);
	inode_dec_link_count(old_dir);
	if (err)
	goto out_dir;
	}
	return 0;


	out_dir:
	if (dir_de) {
	kunmap(dir_page);
	page_cache_release(dir_page);
	}
	out_old:
	kunmap(old_page);
	page_cache_release(old_page);
	out:
	return err;
	}

	const struct inode_operations exofs_dir_inode_operations = {
	.create = exofs_create,
	.lookup = exofs_lookup,
	.link = exofs_link,
	.unlink = exofs_unlink,
	.symlink = exofs_symlink,
	.mkdir = exofs_mkdir,
	.rmdir = exofs_rmdir,
	.mknod = exofs_mknod,
	.rename = exofs_rename,
	.setattr = exofs_setattr,
	};

	const struct inode_operations exofs_special_inode_operations = {
	.setattr = exofs_setattr,
	};