diff options
Diffstat (limited to 'kernel/fs/ceph/acl.c')
| -rw-r--r-- | kernel/fs/ceph/acl.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/kernel/fs/ceph/acl.c b/kernel/fs/ceph/acl.c new file mode 100644 index 000000000..64fa24834 --- /dev/null +++ b/kernel/fs/ceph/acl.c @@ -0,0 +1,263 @@ +/* + * linux/fs/ceph/acl.c + * + * Copyright (C) 2013 Guangliang Zhao, <lucienchao@gmail.com> + * + * 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/ceph/ceph_debug.h> +#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 "super.h" + +static inline void ceph_set_cached_acl(struct inode *inode, + int type, struct posix_acl *acl) +{ + struct ceph_inode_info *ci = ceph_inode(inode); + + spin_lock(&ci->i_ceph_lock); + if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0)) + set_cached_acl(inode, type, acl); + spin_unlock(&ci->i_ceph_lock); +} + +struct posix_acl *ceph_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 = POSIX_ACL_XATTR_ACCESS; + break; + case ACL_TYPE_DEFAULT: + name = POSIX_ACL_XATTR_DEFAULT; + break; + default: + BUG(); + } + + size = __ceph_getxattr(inode, name, "", 0); + if (size > 0) { + value = kzalloc(size, GFP_NOFS); + if (!value) + return ERR_PTR(-ENOMEM); + size = __ceph_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); + + if (!IS_ERR(acl)) + ceph_set_cached_acl(inode, type, acl); + + return acl; +} + +int ceph_set_acl(struct inode *inode, struct posix_acl *acl, int type) +{ + int ret = 0, size = 0; + const char *name = NULL; + char *value = NULL; + struct iattr newattrs; + umode_t new_mode = inode->i_mode, old_mode = inode->i_mode; + struct dentry *dentry; + + switch (type) { + case ACL_TYPE_ACCESS: + name = POSIX_ACL_XATTR_ACCESS; + if (acl) { + ret = posix_acl_equiv_mode(acl, &new_mode); + if (ret < 0) + goto out; + if (ret == 0) + acl = NULL; + } + break; + case ACL_TYPE_DEFAULT: + if (!S_ISDIR(inode->i_mode)) { + ret = acl ? -EINVAL : 0; + goto out; + } + name = POSIX_ACL_XATTR_DEFAULT; + break; + default: + ret = -EINVAL; + goto out; + } + + if (acl) { + size = posix_acl_xattr_size(acl->a_count); + value = kmalloc(size, GFP_NOFS); + if (!value) { + ret = -ENOMEM; + goto out; + } + + ret = posix_acl_to_xattr(&init_user_ns, acl, value, size); + if (ret < 0) + goto out_free; + } + + dentry = d_find_alias(inode); + if (new_mode != old_mode) { + newattrs.ia_mode = new_mode; + newattrs.ia_valid = ATTR_MODE; + ret = ceph_setattr(dentry, &newattrs); + if (ret) + goto out_dput; + } + + ret = __ceph_setxattr(dentry, name, value, size, 0); + if (ret) { + if (new_mode != old_mode) { + newattrs.ia_mode = old_mode; + newattrs.ia_valid = ATTR_MODE; + ceph_setattr(dentry, &newattrs); + } + goto out_dput; + } + + ceph_set_cached_acl(inode, type, acl); + +out_dput: + dput(dentry); +out_free: + kfree(value); +out: + return ret; +} + +int ceph_pre_init_acls(struct inode *dir, umode_t *mode, + struct ceph_acls_info *info) +{ + struct posix_acl *acl, *default_acl; + size_t val_size1 = 0, val_size2 = 0; + struct ceph_pagelist *pagelist = NULL; + void *tmp_buf = NULL; + int err; + + err = posix_acl_create(dir, mode, &default_acl, &acl); + if (err) + return err; + + if (acl) { + int ret = posix_acl_equiv_mode(acl, mode); + if (ret < 0) + goto out_err; + if (ret == 0) { + posix_acl_release(acl); + acl = NULL; + } + } + + if (!default_acl && !acl) + return 0; + + if (acl) + val_size1 = posix_acl_xattr_size(acl->a_count); + if (default_acl) + val_size2 = posix_acl_xattr_size(default_acl->a_count); + + err = -ENOMEM; + tmp_buf = kmalloc(max(val_size1, val_size2), GFP_NOFS); + if (!tmp_buf) + goto out_err; + pagelist = kmalloc(sizeof(struct ceph_pagelist), GFP_NOFS); + if (!pagelist) + goto out_err; + ceph_pagelist_init(pagelist); + + err = ceph_pagelist_reserve(pagelist, PAGE_SIZE); + if (err) + goto out_err; + + ceph_pagelist_encode_32(pagelist, acl && default_acl ? 2 : 1); + + if (acl) { + size_t len = strlen(POSIX_ACL_XATTR_ACCESS); + err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8); + if (err) + goto out_err; + ceph_pagelist_encode_string(pagelist, POSIX_ACL_XATTR_ACCESS, + len); + err = posix_acl_to_xattr(&init_user_ns, acl, + tmp_buf, val_size1); + if (err < 0) + goto out_err; + ceph_pagelist_encode_32(pagelist, val_size1); + ceph_pagelist_append(pagelist, tmp_buf, val_size1); + } + if (default_acl) { + size_t len = strlen(POSIX_ACL_XATTR_DEFAULT); + err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8); + if (err) + goto out_err; + err = ceph_pagelist_encode_string(pagelist, + POSIX_ACL_XATTR_DEFAULT, len); + err = posix_acl_to_xattr(&init_user_ns, default_acl, + tmp_buf, val_size2); + if (err < 0) + goto out_err; + ceph_pagelist_encode_32(pagelist, val_size2); + ceph_pagelist_append(pagelist, tmp_buf, val_size2); + } + + kfree(tmp_buf); + + info->acl = acl; + info->default_acl = default_acl; + info->pagelist = pagelist; + return 0; + +out_err: + posix_acl_release(acl); + posix_acl_release(default_acl); + kfree(tmp_buf); + if (pagelist) + ceph_pagelist_release(pagelist); + return err; +} + +void ceph_init_inode_acls(struct inode* inode, struct ceph_acls_info *info) +{ + if (!inode) + return; + ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, info->acl); + ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, info->default_acl); +} + +void ceph_release_acls_info(struct ceph_acls_info *info) +{ + posix_acl_release(info->acl); + posix_acl_release(info->default_acl); + if (info->pagelist) + ceph_pagelist_release(info->pagelist); +} |