1 /*
2 * Copyright (c) 2017 Citrix Systems Inc.
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation;
7 * version 2.1 of the License.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; If not, see <http://www.gnu.org/licenses/>.
16 */
17
18 #include <errno.h>
19 #include <fcntl.h>
20 #include <stdint.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <unistd.h>
24
25 #include <sys/ioctl.h>
26 #include <sys/stat.h>
27 #include <sys/types.h>
28
29 #include <xen/xen.h>
30 #include <xen/sys/privcmd.h>
31
32 #include "private.h"
33
34 #ifndef O_CLOEXEC
35 #define O_CLOEXEC 0
36 #endif
37
osdep_xendevicemodel_open(xendevicemodel_handle * dmod)38 int osdep_xendevicemodel_open(xendevicemodel_handle *dmod)
39 {
40 int fd = open("/dev/xen/privcmd", O_RDWR | O_CLOEXEC);
41 privcmd_dm_op_t uop;
42 int rc;
43
44 if (fd < 0) {
45 /*
46 * If the 'new' privcmd interface doesn't exist then don't treat
47 * this as an error, but an old privcmd clearly won't implement
48 * IOCTL_PRIVCMD_DM_OP so don't bother trying to open it.
49 */
50 if (errno == ENOENT || errno == ENXIO || errno == ENODEV)
51 goto out;
52
53 PERROR("Could not obtain handle on privileged command interface");
54 return -1;
55 }
56
57 /*
58 * Check to see if IOCTL_PRIVCMD_DM_OP is implemented as we want to
59 * use that in preference to libxencall.
60 */
61 uop.dom = DOMID_INVALID;
62 uop.num = 0;
63 uop.ubufs = NULL;
64
65 rc = ioctl(fd, IOCTL_PRIVCMD_DM_OP, &uop);
66 if (rc < 0) {
67 close(fd);
68 fd = -1;
69 }
70
71 out:
72 dmod->fd = fd;
73 return 0;
74 }
75
osdep_xendevicemodel_close(xendevicemodel_handle * dmod)76 int osdep_xendevicemodel_close(xendevicemodel_handle *dmod)
77 {
78 if (dmod->fd < 0)
79 return 0;
80
81 return close(dmod->fd);
82 }
83
osdep_xendevicemodel_op(xendevicemodel_handle * dmod,domid_t domid,unsigned int nr_bufs,struct xendevicemodel_buf bufs[])84 int osdep_xendevicemodel_op(xendevicemodel_handle *dmod,
85 domid_t domid, unsigned int nr_bufs,
86 struct xendevicemodel_buf bufs[])
87 {
88 privcmd_dm_op_buf_t *ubufs;
89 privcmd_dm_op_t uop;
90 unsigned int i;
91 int rc;
92
93 if (dmod->fd < 0)
94 return xendevicemodel_xcall(dmod, domid, nr_bufs, bufs);
95
96 ubufs = calloc(nr_bufs, sizeof (*ubufs));
97 if (!ubufs)
98 return -1;
99
100 for (i = 0; i < nr_bufs; i++) {
101 ubufs[i].uptr = bufs[i].ptr;
102 ubufs[i].size = bufs[i].size;
103 }
104
105 uop.dom = domid;
106 uop.num = nr_bufs;
107 uop.ubufs = ubufs;
108
109 rc = ioctl(dmod->fd, IOCTL_PRIVCMD_DM_OP, &uop);
110
111 free(ubufs);
112
113 if (rc < 0)
114 return -1;
115
116 return 0;
117 }
118
osdep_xendevicemodel_restrict(xendevicemodel_handle * dmod,domid_t domid)119 int osdep_xendevicemodel_restrict(xendevicemodel_handle *dmod,
120 domid_t domid)
121 {
122 if (dmod->fd < 0) {
123 errno = EOPNOTSUPP;
124 return -1;
125 }
126
127 return ioctl(dmod->fd, IOCTL_PRIVCMD_RESTRICT, &domid);
128 }
129
130 /*
131 * Local variables:
132 * mode: C
133 * c-file-style: "BSD"
134 * c-basic-offset: 4
135 * tab-width: 4
136 * indent-tabs-mode: nil
137 * End:
138 */
139