/*
* Inode operation get_posix_acl().
*
* inode->i_sem: don't care
* BKL: held
*/
struct posix_acl *
ext3_get_acl(struct inode *inode, int type)
{
const size_t max_size = ext3_acl_size(EXT3_ACL_MAX_ENTRIES);
struct ext3_inode_info *ei = EXT3_I(inode);
int name_index;
char *value;
struct posix_acl *acl;
int retval;
if (!IS_POSIXACL(inode))
return 0;
switch(type) {
case ACL_TYPE_ACCESS:
if (ei->i_acl != EXT3_ACL_NOT_CACHED)
return posix_acl_dup(ei->i_acl);
name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
break;
case ACL_TYPE_DEFAULT:
if (ei->i_default_acl != EXT3_ACL_NOT_CACHED)
return posix_acl_dup(ei->i_default_acl);
name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
break;
default:
return ERR_PTR(-EINVAL);
}
value = kmalloc(max_size, GFP_KERNEL);
if (!value)
return ERR_PTR(-ENOMEM);
retval = ext3_xattr_get(inode, name_index, "", value, max_size);
acl = ERR_PTR(retval);
if (retval > 0)
acl = ext3_acl_from_disk(value, retval);
else if (retval == -ENODATA || retval == -ENOSYS)
acl = NULL;
kfree(value);
if (!IS_ERR(acl)) {
switch(type) {
case ACL_TYPE_ACCESS:
ei->i_acl = posix_acl_dup(acl);
break;
case ACL_TYPE_DEFAULT:
ei->i_default_acl = posix_acl_dup(acl);
break;
}
}
return acl;
}
/*
* Convert from in-memory to filesystem representation.
*/
static void *
ext3_acl_to_disk(const struct posix_acl *acl, size_t *size)
{
ext3_acl_header *ext_acl;
char *e;
size_t n;
*size = ext3_acl_size(acl->a_count);
ext_acl = (ext3_acl_header *)kmalloc(sizeof(ext3_acl_header) +
acl->a_count * sizeof(ext3_acl_entry), GFP_KERNEL);
if (!ext_acl)
return ERR_PTR(-ENOMEM);
ext_acl->a_version = cpu_to_le32(EXT3_ACL_VERSION);
e = (char *)ext_acl + sizeof(ext3_acl_header);
for (n=0; n < acl->a_count; n++) {
ext3_acl_entry *entry = (ext3_acl_entry *)e;
entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
switch(acl->a_entries[n].e_tag) {
case ACL_USER:
case ACL_GROUP:
entry->e_id =
cpu_to_le32(acl->a_entries[n].e_id);
e += sizeof(ext3_acl_entry);
break;
case ACL_USER_OBJ:
case ACL_GROUP_OBJ:
case ACL_MASK:
case ACL_OTHER:
e += sizeof(ext3_acl_entry_short);
break;
default:
goto fail;
}
}
return (char *)ext_acl;
fail:
kfree(ext_acl);
return ERR_PTR(-EINVAL);
}
