Esempio n. 1
0
static ssize_t sdcardfskk_write(struct file *file, const char __user *buf,
			    size_t count, loff_t *ppos)
{
	int err = 0;
	struct file *lower_file;
	struct dentry *dentry = file->f_path.dentry;

	/* check disk space */
	if (!check_min_free_space(dentry, count, 0)) {
		printk(KERN_INFO "No minimum free space.\n");
		return -ENOSPC;
	}

	lower_file = sdcardfskk_lower_file(file);
	err = vfs_write(lower_file, buf, count, ppos);
	/* update our inode times+sizes upon a successful lower write */
	if (err >= 0) {
		fsstack_copy_inode_size(dentry->d_inode,
					lower_file->f_path.dentry->d_inode);
		fsstack_copy_attr_times(dentry->d_inode,
					lower_file->f_path.dentry->d_inode);
	}

	return err;
}
static int sdcardfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
	int err = 0;
	struct dentry *lower_dentry;
	struct dentry *lower_parent_dentry = NULL;
	struct path lower_path;

	OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb));

#if defined(LOWER_FS_MIN_FREE_SIZE)
	/* check disk space */
	if (!check_min_free_space(dentry, 0, 1)) {
		REVERT_CRED();
		printk(KERN_INFO "No minimum free space.\n");
		return -ENOSPC;
	}
#endif
	sdcardfs_get_lower_path(dentry, &lower_path);
	lower_dentry = lower_path.dentry;
	lower_parent_dentry = lock_parent(lower_dentry);

	err = mnt_want_write(lower_path.mnt);
	if (err)
		goto out_unlock;

	/* set last 16bytes of mode field to 0775 */
	mode = (mode & S_IFMT) | 00775; 
	err = vfs_mkdir(lower_parent_dentry->d_inode, lower_dentry, mode);

	if (err)
		goto out;

	err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path);
	if (err)
		goto out;

	fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir));
	fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);
	/* update number of links on parent directory */
	dir->i_nlink = sdcardfs_lower_inode(dir)->i_nlink;

out:
	mnt_drop_write(lower_path.mnt);
out_unlock:
	unlock_dir(lower_parent_dentry);
	sdcardfs_put_lower_path(dentry, &lower_path);
	REVERT_CRED();
	return err;
}
Esempio n. 3
0
static int sdcardfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
	int err = 0;
	int make_nomedia_in_obb = 0;
	struct dentry *lower_dentry;
	struct dentry *lower_parent_dentry = NULL;
	struct path lower_path;
	struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);
	const struct cred *saved_cred = NULL;
	struct sdcardfs_inode_info *pi = SDCARDFS_I(dir);
	char *page_buf;
	char *nomedia_dir_name;
	char *nomedia_fullpath;
	int fullpath_namelen;
	int touch_err = 0;

	char *(*d_absolute_path_new)(const struct path *, char *, int) = (void *)kallsyms_lookup_name("d_absolute_path");

	int has_rw = get_caller_has_rw_locked(sbi->pkgl_id, sbi->options.derive);
	if(!check_caller_access_to_name(dir, dentry->d_name.name, sbi->options.derive, 1, has_rw)) {
		err = -EACCES;
		goto out_eacces;
	}

	/* save current_cred and override it */
	OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred);

	/* check disk space */
	if (!check_min_free_space(dentry, 0, 1)) {
		printk(KERN_INFO "sdcardfs: No minimum free space.\n");
		err = -ENOSPC;
		goto out_revert;
	}

	/* the lower_dentry is negative here */
	sdcardfs_get_lower_path(dentry, &lower_path);
	lower_dentry = lower_path.dentry;
	lower_parent_dentry = lock_parent(lower_dentry);

	err = mnt_want_write(lower_path.mnt);
	if (err)
		goto out_unlock;

	/* set last 16bytes of mode field to 0775 */
	mode = (mode & S_IFMT) | 00775; 
	err = vfs_mkdir(lower_parent_dentry->d_inode, lower_dentry, mode);

	if (err)
		goto out;
	
	/* if it is a local obb dentry, setup it with the base obbpath */
	if(need_graft_path(dentry)) {

		err = setup_obb_dentry(dentry, &lower_path);
		if(err) {
			/* if the sbi->obbpath is not available, the lower_path won't be 
			 * changed by setup_obb_dentry() but the lower path is saved to 
             * its orig_path. this dentry will be revalidated later.
			 * but now, the lower_path should be NULL */
			sdcardfs_put_reset_lower_path(dentry);

			/* the newly created lower path which saved to its orig_path or
			 * the lower_path is the base obbpath. 
             * therefore, an additional path_get is required */
			path_get(&lower_path);
		} else
			make_nomedia_in_obb = 1;
	}

	err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path);
	if (err)
		goto out;

	fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir));
	fsstack_copy_inode_size(dir, lower_parent_dentry->d_inode);
	/* update number of links on parent directory */
	set_nlink(dir, sdcardfs_lower_inode(dir)->i_nlink);

	if ((sbi->options.derive == DERIVE_UNIFIED) && (!strcasecmp(dentry->d_name.name, "obb"))
		&& (pi->perm == PERM_ANDROID) && (pi->userid == 0))
		make_nomedia_in_obb = 1;

	/* When creating /Android/data and /Android/obb, mark them as .nomedia */
	if (make_nomedia_in_obb ||
		((pi->perm == PERM_ANDROID) && (!strcasecmp(dentry->d_name.name, "data")))) {

		page_buf = (char *)__get_free_page(GFP_KERNEL);
		if (!page_buf) {
			printk(KERN_ERR "sdcardfs: failed to allocate page buf\n");
			goto out;
		}

		nomedia_dir_name = d_absolute_path_new(&lower_path, page_buf, PAGE_SIZE);
		if (IS_ERR(nomedia_dir_name)) {
			free_page((unsigned long)page_buf);
			printk(KERN_ERR "sdcardfs: failed to get .nomedia dir name\n");
			goto out;
		}

		fullpath_namelen = page_buf + PAGE_SIZE - nomedia_dir_name - 1;
		fullpath_namelen += strlen("/.nomedia");
		nomedia_fullpath = kzalloc(fullpath_namelen + 1, GFP_KERNEL);
		if (!nomedia_fullpath) {
			free_page((unsigned long)page_buf);
			printk(KERN_ERR "sdcardfs: failed to allocate .nomedia fullpath buf\n");
			goto out;
		}

		strcpy(nomedia_fullpath, nomedia_dir_name);
		free_page((unsigned long)page_buf);
		strcat(nomedia_fullpath, "/.nomedia");
		touch_err = touch(nomedia_fullpath, 0664);
		if (touch_err) {
			printk(KERN_ERR "sdcardfs: failed to touch(%s): %d\n",
							nomedia_fullpath, touch_err);
			kfree(nomedia_fullpath);
			goto out;
		}
		kfree(nomedia_fullpath);
	}
out:
	mnt_drop_write(lower_path.mnt);
out_unlock:
	unlock_dir(lower_parent_dentry);
	sdcardfs_put_lower_path(dentry, &lower_path);
out_revert:
	REVERT_CRED(saved_cred);
out_eacces:
	return err;
}