/* * Copyright (C) 2007 Red Hat. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License v2 as published by the Free Software Foundation. * * This program 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 this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #include <linux/fs.h> #include <linux/string.h> #include <linux/xattr.h> #include <linux/posix_acl_xattr.h> #include <linux/posix_acl.h> #include <linux/sched.h> #include <linux/slab.h> #include "ctree.h" #include "btrfs_inode.h" #include "xattr.h" struct posix_acl *btrfs_get_acl(struct inode *inode, int type) { int size; const char *name; char *value = NULL; struct posix_acl *acl; switch (type) { case ACL_TYPE_ACCESS: name = XATTR_NAME_POSIX_ACL_ACCESS; break; case ACL_TYPE_DEFAULT: name = XATTR_NAME_POSIX_ACL_DEFAULT; break; default: BUG(); } size = __btrfs_getxattr(inode, name, "", 0); if (size > 0) { value = kzalloc(size, GFP_KERNEL); if (!value) return ERR_PTR(-ENOMEM); size = __btrfs_getxattr(inode, name, value, size); } if (size > 0) { acl = posix_acl_from_xattr(&init_user_ns, value, size); } else if (size == -ERANGE || size == -ENODATA || size == 0) { acl = NULL; } else { acl = ERR_PTR(-EIO); } kfree(value); return acl; } /* * Needs to be called with fs_mutex held */ static int __btrfs_set_acl(struct btrfs_trans_handle *trans, struct inode *inode, struct posix_acl *acl, int type) { int ret, size = 0; const char *name; char *value = NULL; switch (type) { case ACL_TYPE_ACCESS: name = XATTR_NAME_POSIX_ACL_ACCESS; if (acl) { ret = posix_acl_update_mode(inode, &inode->i_mode, &acl); if (ret) return ret; } ret = 0; break; case ACL_TYPE_DEFAULT: if (!S_ISDIR(inode->i_mode)) return acl ? -EINVAL : 0; name = XATTR_NAME_POSIX_ACL_DEFAULT; break; default: return -EINVAL; } if (acl) { size = posix_acl_xattr_size(acl->a_count); value = kmalloc(size, GFP_KERNEL); if (!value) { ret = -ENOMEM; goto out; } ret = posix_acl_to_xattr(&init_user_ns, acl, value, size); if (ret < 0) goto out; } ret = __btrfs_setxattr(trans, inode, name, value, size, 0); out: kfree(value); if (!ret) set_cached_acl(inode, type, acl); return ret; } int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type) { return __btrfs_set_acl(NULL, inode, acl, type); } /* * btrfs_init_acl is already generally called under fs_mutex, so the locking * stuff has been fixed to work with that. If the locking stuff changes, we * need to re-evaluate the acl locking stuff. */ int btrfs_init_acl(struct btrfs_trans_handle *trans, struct inode *inode, struct inode *dir) { struct posix_acl *default_acl, *acl; int ret = 0; /* this happens with subvols */ if (!dir) return 0; ret = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl); if (ret) return ret; if (default_acl) { ret = __btrfs_set_acl(trans, inode, default_acl, ACL_TYPE_DEFAULT); posix_acl_release(default_acl); } if (acl) { if (!ret) ret = __btrfs_set_acl(trans, inode, acl, ACL_TYPE_ACCESS); posix_acl_release(acl); } if (!default_acl && !acl) cache_no_acl(inode); return ret; }