1/*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source.  A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12/*
13 * Copyright 2017 Nexenta Inc.  All rights reserved.
14 */
15
16/* needed when building libzpool */
17#ifndef	_KERNEL
18#include <sys/zfs_context.h>
19#endif
20
21#include <sys/sunddi.h>
22#include <sys/dkio.h>
23#include <sys/dkioc_free_util.h>
24#include <sys/sysmacros.h>
25#include <sys/file.h>
26#include <sys/sdt.h>
27
28/*
29 * Copy-in convenience function for variable-length dkioc_free_list_t
30 * structures. The pointer to be copied from is in `arg' (may be a pointer
31 * to userspace). A new buffer is allocated and a pointer to it is placed
32 * in `out'. `ddi_flags' indicates whether the pointer is from user-
33 * or kernelspace (FKIOCTL) and `kmflags' are the flags passed to
34 * kmem_zalloc when allocating the new structure.
35 * Returns 0 on success, or an errno on failure.
36 */
37int
38dfl_copyin(void *arg, dkioc_free_list_t **out, int ddi_flags, int kmflags)
39{
40	dkioc_free_list_t *dfl;
41
42	if (ddi_flags & FKIOCTL) {
43		dkioc_free_list_t *dfl_in = arg;
44
45		if (dfl_in->dfl_num_exts == 0 ||
46		    dfl_in->dfl_num_exts > DFL_COPYIN_MAX_EXTS)
47			return (SET_ERROR(EINVAL));
48		dfl = kmem_alloc(DFL_SZ(dfl_in->dfl_num_exts), kmflags);
49		if (dfl == NULL)
50			return (SET_ERROR(ENOMEM));
51		bcopy(dfl_in, dfl, DFL_SZ(dfl_in->dfl_num_exts));
52	} else {
53		uint64_t num_exts;
54
55		if (ddi_copyin(((uint8_t *)arg) + offsetof(dkioc_free_list_t,
56		    dfl_num_exts), &num_exts, sizeof (num_exts),
57		    ddi_flags) != 0)
58			return (SET_ERROR(EFAULT));
59		if (num_exts == 0 || num_exts > DFL_COPYIN_MAX_EXTS)
60			return (SET_ERROR(EINVAL));
61		dfl = kmem_alloc(DFL_SZ(num_exts), kmflags);
62		if (dfl == NULL)
63			return (SET_ERROR(ENOMEM));
64		if (ddi_copyin(arg, dfl, DFL_SZ(num_exts), ddi_flags) != 0 ||
65		    dfl->dfl_num_exts != num_exts) {
66			kmem_free(dfl, DFL_SZ(num_exts));
67			return (SET_ERROR(EFAULT));
68		}
69	}
70
71	*out = dfl;
72	return (0);
73}
74
75/* Frees a variable-length dkioc_free_list_t structure. */
76void
77dfl_free(dkioc_free_list_t *dfl)
78{
79	kmem_free(dfl, DFL_SZ(dfl->dfl_num_exts));
80}
81