--- /dev/null
+ /*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+ #include <linux/kernel.h>
+ #include <linux/fs.h>
+ #include <linux/richacl_xattr.h>
+
+ #include "ext4.h"
+ #include "ext4_jbd2.h"
+ #include "xattr.h"
+ #include "acl.h"
+ #include "richacl.h"
+
+ static inline struct richacl *
+ ext4_iget_richacl(struct inode *inode)
+ {
+ struct richacl *acl = EXT4_RICHACL_NOT_CACHED;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+
+ spin_lock(&inode->i_lock);
+ if (ei->i_richacl != EXT4_RICHACL_NOT_CACHED)
+ acl = richacl_get(ei->i_richacl);
+ spin_unlock(&inode->i_lock);
+
+ return acl;
+ }
+
+ static inline void
+ ext4_iset_richacl(struct inode *inode, struct richacl *acl)
+ {
+ struct ext4_inode_info *ei = EXT4_I(inode);
+
+ spin_lock(&inode->i_lock);
+ if (ei->i_richacl != EXT4_RICHACL_NOT_CACHED)
+ richacl_put(ei->i_richacl);
+ ei->i_richacl = richacl_get(acl);
+ spin_unlock(&inode->i_lock);
+ }
+
+ static struct richacl *
+ ext4_get_richacl(struct inode *inode)
+ {
+ const int name_index = EXT4_XATTR_INDEX_RICHACL;
+ void *value = NULL;
+ struct richacl *acl;
+ int retval;
+
+ if (!IS_RICHACL(inode))
+ return ERR_PTR(-EOPNOTSUPP);
+ acl = ext4_iget_richacl(inode);
+ if (acl != EXT4_RICHACL_NOT_CACHED)
+ return acl;
+ retval = ext4_xattr_get(inode, name_index, "", NULL, 0);
+ if (retval > 0) {
+ value = kmalloc(retval, GFP_KERNEL);
+ if (!value)
+ return ERR_PTR(-ENOMEM);
+ retval = ext4_xattr_get(inode, name_index, "", value, retval);
+ }
+ if (retval > 0) {
+ acl = richacl_from_xattr(value, retval);
+ if (acl == ERR_PTR(-EINVAL))
+ acl = ERR_PTR(-EIO);
+ } else if (retval == -ENODATA || retval == -ENOSYS)
+ acl = NULL;
+ else
+ acl = ERR_PTR(retval);
+ kfree(value);
+
+ if (!IS_ERR_OR_NULL(acl))
+ ext4_iset_richacl(inode, acl);
+
+ return acl;
+ }
+
+ static int
+ ext4_set_richacl(handle_t *handle, struct inode *inode, struct richacl *acl)
+ {
+ const int name_index = EXT4_XATTR_INDEX_RICHACL;
+ size_t size = 0;
+ void *value = NULL;
+ int retval;
+
+ if (acl) {
+ mode_t mode = inode->i_mode;
+ if (richacl_equiv_mode(acl, &mode) == 0) {
+ inode->i_mode = mode;
+ ext4_mark_inode_dirty(handle, inode);
+ acl = NULL;
+ }
+ }
+ if (acl) {
+ size = richacl_xattr_size(acl);
+ value = kmalloc(size, GFP_KERNEL);
+ if (!value)
+ return -ENOMEM;
+ richacl_to_xattr(acl, value);
+ }
+ if (handle)
+ retval = ext4_xattr_set_handle(handle, inode, name_index, "",
+ value, size, 0);
+ else
+ retval = ext4_xattr_set(inode, name_index, "", value, size, 0);
+ kfree(value);
+ if (!retval)
+ ext4_iset_richacl(inode, acl);
+
+ return retval;
+ }
+
+ int
+ ext4_richacl_permission(struct inode *inode, unsigned int mask)
+ {
+ struct richacl *acl;
+ int retval;
+
+ if (!IS_RICHACL(inode))
+ BUG();
+
+ acl = ext4_get_richacl(inode);
+ if (acl && IS_ERR(acl))
+ retval = PTR_ERR(acl);
+ else {
+ retval = richacl_inode_permission(inode, acl, mask);
+ richacl_put(acl);
+ }
+
+ return retval;
+ }
+
+ int ext4_permission(struct inode *inode, int mask)
+ {
+ if (IS_RICHACL(inode))
+ return ext4_richacl_permission(inode,
+ richacl_want_to_mask(mask));
+ else
+ return generic_permission(inode, mask, ext4_check_acl);
+ }
+
+ int ext4_may_create(struct inode *dir, int isdir)
+ {
+ return richacl_may_create(dir, isdir, ext4_richacl_permission);
+ }
+
+ int ext4_may_delete(struct inode *dir, struct inode *inode, int replace)
+ {
+ return richacl_may_delete(dir, inode, replace, ext4_richacl_permission);
+ }
+
+ int
+ ext4_init_richacl(handle_t *handle, struct inode *inode, struct inode *dir)
+ {
+ struct richacl *dir_acl = NULL;
+
+ if (!S_ISLNK(inode->i_mode)) {
+ dir_acl = ext4_get_richacl(dir);
+ if (IS_ERR(dir_acl))
+ return PTR_ERR(dir_acl);
+ }
+ if (dir_acl) {
+ struct richacl *acl;
+ int retval;
+
+ acl = richacl_inherit(dir_acl, inode);
+ richacl_put(dir_acl);
+
+ retval = PTR_ERR(acl);
+ if (acl && !IS_ERR(acl)) {
+ retval = ext4_set_richacl(handle, inode, acl);
+ richacl_put(acl);
+ }
+ return retval;
+ } else {
+ inode->i_mode &= ~current_umask();
+ return 0;
+ }
+ }
+
+ int
+ ext4_richacl_chmod(struct inode *inode)
+ {
+ struct richacl *acl;
+ int retval;
+
+ if (S_ISLNK(inode->i_mode))
+ return -EOPNOTSUPP;
+ acl = ext4_get_richacl(inode);
+ if (IS_ERR_OR_NULL(acl))
+ return PTR_ERR(acl);
+ acl = richacl_chmod(acl, inode->i_mode);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ retval = ext4_set_richacl(NULL, inode, acl);
+ richacl_put(acl);
+
+ return retval;
+ }
+
+ static size_t
+ ext4_xattr_list_richacl(struct dentry *dentry, char *list, size_t list_len,
+ const char *name, size_t name_len, int type)
+ {
+ const size_t size = sizeof(RICHACL_XATTR);
+ if (!IS_RICHACL(dentry->d_inode))
+ return 0;
+ if (list && size <= list_len)
+ memcpy(list, RICHACL_XATTR, size);
+ return size;
+ }
+
+ static int
+ ext4_xattr_get_richacl(struct dentry *dentry, const char *name, void *buffer,
+ size_t buffer_size, int type)
+ {
+ struct richacl *acl;
+ size_t size;
+
+ if (strcmp(name, "") != 0)
+ return -EINVAL;
+ acl = ext4_get_richacl(dentry->d_inode);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ if (acl == NULL)
+ return -ENODATA;
+ size = richacl_xattr_size(acl);
+ if (buffer) {
+ if (size > buffer_size)
+ return -ERANGE;
+ richacl_to_xattr(acl, buffer);
+ }
+ richacl_put(acl);
+
+ return size;
+ }
+
+ static int
+ ext4_xattr_set_richacl(struct dentry *dentry, const char *name,
+ const void *value, size_t size, int flags, int type)
+ {
+ handle_t *handle;
+ struct richacl *acl = NULL;
+ int retval, retries = 0;
+ struct inode *inode = dentry->d_inode;
+
+ if (!IS_RICHACL(dentry->d_inode))
+ return -EOPNOTSUPP;
+ if (S_ISLNK(inode->i_mode))
+ return -EOPNOTSUPP;
+ if (strcmp(name, "") != 0)
+ return -EINVAL;
+ if (current_fsuid() != inode->i_uid &&
+ ext4_richacl_permission(inode, ACE4_WRITE_ACL) &&
+ !capable(CAP_FOWNER))
+ return -EPERM;
+ if (value) {
+ acl = richacl_from_xattr(value, size);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+
+ inode->i_mode &= ~S_IRWXUGO;
+ inode->i_mode |= richacl_masks_to_mode(acl);
+ }
+
+ retry:
+ handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ext4_mark_inode_dirty(handle, inode);
+ retval = ext4_set_richacl(handle, inode, acl);
+ ext4_journal_stop(handle);
+ if (retval == ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+ goto retry;
+ richacl_put(acl);
+ return retval;
+ }
+
-struct xattr_handler ext4_richacl_xattr_handler = {
++const struct xattr_handler ext4_richacl_xattr_handler = {
+ .prefix = RICHACL_XATTR,
+ .list = ext4_xattr_list_richacl,
+ .get = ext4_xattr_get_richacl,
+ .set = ext4_xattr_set_richacl,
+ };
projects / linux-flexiantxendom0-3.2.10.git / commitdiff