1  /******************************************************************************
2  *
3  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
4  * Use is subject to license terms.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation;
9  * version 2.1 of the License.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; If not, see <http://www.gnu.org/licenses/>.
18  *
19  * Split from xc_freebsd_osdep.c
20  */
21 
22 #include <errno.h>
23 #include <fcntl.h>
24 #include <stdint.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <unistd.h>
28 
29 #include <sys/mman.h>
30 #include <sys/ioctl.h>
31 
32 #include "private.h"
33 
34 #define PRIVCMD_DEV     "/dev/xen/privcmd"
35 
osdep_xencall_open(xencall_handle * xcall)36 int osdep_xencall_open(xencall_handle *xcall)
37 {
38     int fd = open(PRIVCMD_DEV, O_RDWR|O_CLOEXEC);
39 
40     /*
41      * This file descriptor is opaque to the caller, thus we are
42      * polite and try and ensure it doesn't propagate (ie leak)
43      * outside the process, by using O_CLOEXEC.
44      */
45 
46     if ( fd == -1 )
47     {
48         PERROR("Could not obtain handle on privileged command interface "
49                PRIVCMD_DEV);
50         return -1;
51     }
52 
53     xcall->fd = fd;
54     return 0;
55 }
56 
osdep_xencall_close(xencall_handle * xcall)57 int osdep_xencall_close(xencall_handle *xcall)
58 {
59     int fd = xcall->fd;
60     if ( fd == -1 )
61         return 0;
62     return close(fd);
63 }
64 
osdep_hypercall(xencall_handle * xcall,privcmd_hypercall_t * hypercall)65 int osdep_hypercall(xencall_handle *xcall, privcmd_hypercall_t *hypercall)
66 {
67     int fd = xcall->fd;
68     int ret;
69 
70     ret = ioctl(fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
71 
72     return (ret == 0) ? hypercall->retval : ret;
73 }
74 
osdep_alloc_pages(xencall_handle * xcall,size_t npages)75 void *osdep_alloc_pages(xencall_handle *xcall, size_t npages)
76 {
77     size_t size = npages * PAGE_SIZE;
78     void *p;
79 
80     /* Address returned by mmap is page aligned. */
81     p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
82              -1, 0);
83     if (p == NULL)
84         return NULL;
85 
86     /*
87      * Since FreeBSD doesn't have the MAP_LOCKED flag,
88      * lock memory using mlock.
89      */
90     if ( mlock(p, size) < 0 )
91     {
92         munmap(p, size);
93         return NULL;
94     }
95 
96     return p;
97 }
98 
osdep_free_pages(xencall_handle * xcall,void * ptr,size_t npages)99 void osdep_free_pages(xencall_handle *xcall, void *ptr, size_t npages)
100 {
101     int saved_errno = errno;
102     /* Unlock pages */
103     munlock(ptr, npages * PAGE_SIZE);
104 
105     munmap(ptr, npages * PAGE_SIZE);
106     /* We MUST propagate the hypercall errno, not unmap call's. */
107     errno = saved_errno;
108 }
109 
xencall_buffers_never_fault(xencall_handle * xcall)110 int xencall_buffers_never_fault(xencall_handle *xcall)
111 {
112     return 1;
113 }
114 
115 /*
116  * Local variables:
117  * mode: C
118  * c-file-style: "BSD"
119  * c-basic-offset: 4
120  * tab-width: 4
121  * indent-tabs-mode: nil
122  * End:
123  */
124