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
20 #include <unistd.h>
21 #include <fcntl.h>
22 #include <errno.h>
23 #include <sys/mman.h>
24 #include <sys/ioctl.h>
25
26 #include "private.h"
27
osdep_xenforeignmemory_open(xenforeignmemory_handle * fmem)28 int osdep_xenforeignmemory_open(xenforeignmemory_handle *fmem)
29 {
30 int flags, saved_errno;
31 int fd = open("/kern/xen/privcmd", O_RDWR);
32
33 if ( fd == -1 )
34 {
35 PERROR("Could not obtain handle on privileged command interface");
36 return -1;
37 }
38
39 /* Although we return the file handle as the 'xc handle' the API
40 does not specify / guarentee that this integer is in fact
41 a file handle. Thus we must take responsiblity to ensure
42 it doesn't propagate (ie leak) outside the process */
43 if ( (flags = fcntl(fd, F_GETFD)) < 0 )
44 {
45 PERROR("Could not get file handle flags");
46 goto error;
47 }
48 flags |= FD_CLOEXEC;
49 if ( fcntl(fd, F_SETFD, flags) < 0 )
50 {
51 PERROR("Could not set file handle flags");
52 goto error;
53 }
54
55 fmem->fd = fd;
56 return 0;
57
58 error:
59 saved_errno = errno;
60 close(fd);
61 errno = saved_errno;
62 return -1;
63 }
64
osdep_xenforeignmemory_close(xenforeignmemory_handle * fmem)65 int osdep_xenforeignmemory_close(xenforeignmemory_handle *fmem)
66 {
67 int fd = fmem->fd;
68 return close(fd);
69 }
70
osdep_xenforeignmemory_map(xenforeignmemory_handle * fmem,uint32_t dom,void * addr,int prot,int flags,size_t num,const xen_pfn_t arr[],int err[])71 void *osdep_xenforeignmemory_map(xenforeignmemory_handle *fmem,
72 uint32_t dom, void *addr,
73 int prot, int flags, size_t num,
74 const xen_pfn_t arr[/*num*/], int err[/*num*/])
75
76 {
77 int fd = fmem->fd;
78 privcmd_mmapbatch_v2_t ioctlx;
79 addr = mmap(addr, num * XC_PAGE_SIZE, prot,
80 flags | MAP_ANON | MAP_SHARED, -1, 0);
81 if ( addr == MAP_FAILED ) {
82 PERROR("osdep_xenforeignmemory_map: mmap failed");
83 return NULL;
84 }
85
86 ioctlx.num=num;
87 ioctlx.dom=dom;
88 ioctlx.addr=(unsigned long)addr;
89 ioctlx.arr=arr;
90 ioctlx.err=err;
91
92 if ( ioctl(fd, IOCTL_PRIVCMD_MMAPBATCH_V2, &ioctlx) < 0 )
93 {
94 int saved_errno = errno;
95 PERROR("osdep_xenforeignmemory_map: ioctl failed");
96 munmap(addr, num * XC_PAGE_SIZE);
97 errno = saved_errno;
98 return NULL;
99 }
100 return addr;
101
102 }
103
osdep_xenforeignmemory_unmap(xenforeignmemory_handle * fmem,void * addr,size_t num)104 int osdep_xenforeignmemory_unmap(xenforeignmemory_handle *fmem,
105 void *addr, size_t num)
106 {
107 return munmap(addr, num * XC_PAGE_SIZE);
108 }
109
osdep_xenforeignmemory_restrict(xenforeignmemory_handle * fmem,domid_t domid)110 int osdep_xenforeignmemory_restrict(xenforeignmemory_handle *fmem,
111 domid_t domid)
112 {
113 errno = EOPNOTSUPP;
114 return -1;
115 }
116
osdep_xenforeignmemory_unmap_resource(xenforeignmemory_handle * fmem,xenforeignmemory_resource_handle * fres)117 int osdep_xenforeignmemory_unmap_resource(
118 xenforeignmemory_handle *fmem, xenforeignmemory_resource_handle *fres)
119 {
120 return fres ? munmap(fres->addr, fres->nr_frames << XC_PAGE_SHIFT) : 0;
121 }
122
osdep_xenforeignmemory_map_resource(xenforeignmemory_handle * fmem,xenforeignmemory_resource_handle * fres)123 int osdep_xenforeignmemory_map_resource(
124 xenforeignmemory_handle *fmem, xenforeignmemory_resource_handle *fres)
125 {
126 privcmd_mmap_resource_t mr = {
127 .dom = fres->domid,
128 .type = fres->type,
129 .id = fres->id,
130 .idx = fres->frame,
131 .num = fres->nr_frames,
132 };
133 int rc;
134
135 if ( !fres->addr && !fres->nr_frames )
136 /* Request for resource size. Skip mmap(). */
137 goto skip_mmap;
138
139 fres->addr = mmap(fres->addr, fres->nr_frames << XC_PAGE_SHIFT,
140 fres->prot, fres->flags | MAP_ANON | MAP_SHARED, -1, 0);
141 if ( fres->addr == MAP_FAILED )
142 return -1;
143
144 mr.addr = (uintptr_t)fres->addr;
145
146 skip_mmap:
147 rc = ioctl(fmem->fd, IOCTL_PRIVCMD_MMAP_RESOURCE, &mr);
148 if ( rc )
149 {
150 if ( errno == ENOSYS )
151 errno = EOPNOTSUPP;
152
153 if ( fres->addr )
154 {
155 int saved_errno = errno;
156
157 osdep_xenforeignmemory_unmap_resource(fmem, fres);
158 errno = saved_errno;
159 }
160
161 return -1;
162 }
163
164 /* If requesting size, copy back. */
165 if ( !fres->addr )
166 fres->nr_frames = mr.num;
167
168 return 0;
169 }
170
171 /*
172 * Local variables:
173 * mode: C
174 * c-file-style: "BSD"
175 * c-basic-offset: 4
176 * tab-width: 4
177 * indent-tabs-mode: nil
178 * End:
179 */
180