1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * libfmd_agent contains the low-level operations that needed by the fmd
29  * agents, such as page operations (status/retire/unretire), cpu operations
30  * (status/online/offline), etc.
31  *
32  * Some operations are implemented by /dev/fm ioctls.  Those ioctls are
33  * heavily versioned to allow userland patching without requiring a reboot
34  * to get a matched /dev/fm.   All the ioctls use packed nvlist to interact
35  * between userland and kernel.  (see fmd_agent_nvl_ioctl()).
36  */
37 
38 #include <fcntl.h>
39 #include <errno.h>
40 #include <unistd.h>
41 #include <strings.h>
42 #include <libnvpair.h>
43 #include <string.h>
44 #include <sys/types.h>
45 #include <sys/devfm.h>
46 #include <fmd_agent_impl.h>
47 
48 int
49 fmd_agent_errno(fmd_agent_hdl_t *hdl)
50 {
51 	return (hdl->agent_errno);
52 }
53 
54 int
55 fmd_agent_seterrno(fmd_agent_hdl_t *hdl, int err)
56 {
57 	hdl->agent_errno = err;
58 	return (-1);
59 }
60 
61 const char *
62 fmd_agent_strerr(int err)
63 {
64 	return (strerror(err));
65 }
66 
67 const char *
68 fmd_agent_errmsg(fmd_agent_hdl_t *hdl)
69 {
70 	return (fmd_agent_strerr(hdl->agent_errno));
71 }
72 
73 static int
74 cleanup_set_errno(fmd_agent_hdl_t *hdl, nvlist_t *innvl, nvlist_t *outnvl,
75     int err)
76 {
77 	if (innvl != NULL)
78 		nvlist_free(innvl);
79 	if (outnvl != NULL)
80 		nvlist_free(outnvl);
81 	return (fmd_agent_seterrno(hdl, err));
82 }
83 
84 /*
85  * Perform /dev/fm ioctl.  The input and output data are represented by
86  * name-value lists (nvlists).
87  */
88 int
89 fmd_agent_nvl_ioctl(fmd_agent_hdl_t *hdl, int cmd, uint32_t ver,
90     nvlist_t *innvl, nvlist_t **outnvlp)
91 {
92 	fm_ioc_data_t fid;
93 	int err = 0;
94 	char *inbuf = NULL, *outbuf = NULL;
95 	size_t insz = 0, outsz = 0;
96 
97 	if (innvl != NULL) {
98 		if ((err = nvlist_size(innvl, &insz, NV_ENCODE_NATIVE)) != 0)
99 			return (err);
100 		if (insz > FM_IOC_MAXBUFSZ)
101 			return (ENAMETOOLONG);
102 		if ((inbuf = umem_alloc(insz, UMEM_DEFAULT)) == NULL)
103 			return (errno);
104 
105 		if ((err = nvlist_pack(innvl, &inbuf, &insz,
106 		    NV_ENCODE_NATIVE, 0)) != 0) {
107 			umem_free(inbuf, insz);
108 			return (err);
109 		}
110 	}
111 
112 	if (outnvlp != NULL) {
113 		outsz = FM_IOC_OUT_BUFSZ;
114 	}
115 	for (;;) {
116 		if (outnvlp != NULL) {
117 			outbuf = umem_alloc(outsz, UMEM_DEFAULT);
118 			if (outbuf == NULL) {
119 				err = errno;
120 				break;
121 			}
122 		}
123 
124 		fid.fid_version = ver;
125 		fid.fid_insz = insz;
126 		fid.fid_inbuf = inbuf;
127 		fid.fid_outsz = outsz;
128 		fid.fid_outbuf = outbuf;
129 
130 		if (ioctl(hdl->agent_devfd, cmd, &fid) < 0) {
131 			if (errno == ENAMETOOLONG && outsz != 0 &&
132 			    outsz < (FM_IOC_OUT_MAXBUFSZ / 2)) {
133 				umem_free(outbuf, outsz);
134 				outsz *= 2;
135 				outbuf = umem_alloc(outsz, UMEM_DEFAULT);
136 				if (outbuf == NULL) {
137 					err = errno;
138 					break;
139 				}
140 			} else {
141 				err = errno;
142 				break;
143 			}
144 		} else if (outnvlp != NULL) {
145 			err = nvlist_unpack(fid.fid_outbuf, fid.fid_outsz,
146 			    outnvlp, 0);
147 			break;
148 		} else {
149 			break;
150 		}
151 	}
152 
153 	if (inbuf != NULL)
154 		umem_free(inbuf, insz);
155 	if (outbuf != NULL)
156 		umem_free(outbuf, outsz);
157 
158 	return (err);
159 }
160 
161 /*
162  * Open /dev/fm and return a handle.  ver is the overall interface version.
163  */
164 static fmd_agent_hdl_t *
165 fmd_agent_open_dev(int ver, int mode)
166 {
167 	fmd_agent_hdl_t *hdl;
168 	int fd, err;
169 	nvlist_t *nvl;
170 
171 	if ((fd = open("/dev/fm", mode)) < 0)
172 		return (NULL); /* errno is set for us */
173 
174 	if ((hdl = umem_alloc(sizeof (fmd_agent_hdl_t),
175 	    UMEM_DEFAULT)) == NULL) {
176 		err = errno;
177 		(void) close(fd);
178 		errno = err;
179 		return (NULL);
180 	}
181 
182 	hdl->agent_devfd = fd;
183 	hdl->agent_version = ver;
184 
185 	/*
186 	 * Get the individual interface versions.
187 	 */
188 	if ((err = fmd_agent_nvl_ioctl(hdl, FM_IOC_VERSIONS, ver, NULL, &nvl))
189 	    < 0) {
190 		(void) close(fd);
191 		umem_free(hdl, sizeof (fmd_agent_hdl_t));
192 		errno = err;
193 		return (NULL);
194 	}
195 
196 	hdl->agent_ioc_versions = nvl;
197 	return (hdl);
198 }
199 
200 fmd_agent_hdl_t *
201 fmd_agent_open(int ver)
202 {
203 	if (ver > FMD_AGENT_VERSION) {
204 		errno = ENOTSUP;
205 		return (NULL);
206 	}
207 	return (fmd_agent_open_dev(ver, O_RDONLY));
208 }
209 
210 void
211 fmd_agent_close(fmd_agent_hdl_t *hdl)
212 {
213 	(void) close(hdl->agent_devfd);
214 	nvlist_free(hdl->agent_ioc_versions);
215 	umem_free(hdl, sizeof (fmd_agent_hdl_t));
216 }
217 
218 /*
219  * Given a interface name, return the kernel interface version.
220  */
221 int
222 fmd_agent_version(fmd_agent_hdl_t *hdl, const char *op, uint32_t *verp)
223 {
224 	int err;
225 
226 	err = nvlist_lookup_uint32(hdl->agent_ioc_versions,
227 	    op, verp);
228 
229 	if (err != 0) {
230 		errno = err;
231 		return (-1);
232 	}
233 	return (0);
234 }
235 
236 static int
237 fmd_agent_pageop_v1(fmd_agent_hdl_t *hdl, int cmd, nvlist_t *fmri)
238 {
239 	int err;
240 	nvlist_t *nvl = NULL;
241 
242 	if ((err = nvlist_alloc(&nvl, NV_UNIQUE_NAME_TYPE, 0)) != 0 ||
243 	    (err = nvlist_add_nvlist(nvl, FM_PAGE_RETIRE_FMRI, fmri)) != 0 ||
244 	    (err = fmd_agent_nvl_ioctl(hdl, cmd, 1, nvl, NULL)) != 0)
245 		return (cleanup_set_errno(hdl, nvl, NULL, err));
246 
247 	nvlist_free(nvl);
248 	return (0);
249 }
250 
251 static int
252 fmd_agent_pageop(fmd_agent_hdl_t *hdl, int cmd, nvlist_t *fmri)
253 {
254 	uint32_t ver;
255 
256 	if (fmd_agent_version(hdl, FM_PAGE_OP_VERSION, &ver) == -1)
257 		return (fmd_agent_seterrno(hdl, errno));
258 
259 	switch (ver) {
260 	case 1:
261 		return (fmd_agent_pageop_v1(hdl, cmd, fmri));
262 
263 	default:
264 		return (fmd_agent_seterrno(hdl, ENOTSUP));
265 	}
266 }
267 
268 int
269 fmd_agent_page_retire(fmd_agent_hdl_t *hdl, nvlist_t *fmri)
270 {
271 	int rc = fmd_agent_pageop(hdl, FM_IOC_PAGE_RETIRE, fmri);
272 	int err = fmd_agent_errno(hdl);
273 
274 	/*
275 	 * FM_IOC_PAGE_RETIRE ioctl returns:
276 	 *   0 - success in retiring page
277 	 *   -1, errno = EIO - page is already retired
278 	 *   -1, errno = EAGAIN - page is scheduled for retirement
279 	 *   -1, errno = EINVAL - page fmri is invalid
280 	 *   -1, errno = any else - error
281 	 */
282 	if (rc == 0 || err == EIO || err == EINVAL) {
283 		if (rc == 0)
284 			(void) fmd_agent_seterrno(hdl, 0);
285 		return (FMD_AGENT_RETIRE_DONE);
286 	}
287 	if (err == EAGAIN)
288 		return (FMD_AGENT_RETIRE_ASYNC);
289 
290 	return (FMD_AGENT_RETIRE_FAIL);
291 }
292 
293 int
294 fmd_agent_page_unretire(fmd_agent_hdl_t *hdl, nvlist_t *fmri)
295 {
296 	int rc = fmd_agent_pageop(hdl, FM_IOC_PAGE_UNRETIRE, fmri);
297 	int err = fmd_agent_errno(hdl);
298 
299 	/*
300 	 * FM_IOC_PAGE_UNRETIRE ioctl returns:
301 	 *   0 - success in unretiring page
302 	 *   -1, errno = EIO - page is already unretired
303 	 *   -1, errno = EAGAIN - page couldn't be locked, still retired
304 	 *   -1, errno = EINVAL - page fmri is invalid
305 	 *   -1, errno = any else - error
306 	 */
307 	if (rc == 0 || err == EIO || err == EINVAL) {
308 		if (rc == 0)
309 			(void) fmd_agent_seterrno(hdl, 0);
310 		return (FMD_AGENT_RETIRE_DONE);
311 	}
312 
313 	return (FMD_AGENT_RETIRE_FAIL);
314 }
315 
316 int
317 fmd_agent_page_isretired(fmd_agent_hdl_t *hdl, nvlist_t *fmri)
318 {
319 	int rc = fmd_agent_pageop(hdl, FM_IOC_PAGE_STATUS, fmri);
320 	int err = fmd_agent_errno(hdl);
321 
322 	/*
323 	 * FM_IOC_PAGE_STATUS returns:
324 	 *   0 - page is retired
325 	 *   -1, errno = EAGAIN - page is scheduled for retirement
326 	 *   -1, errno = EIO - page not scheduled for retirement
327 	 *   -1, errno = EINVAL - page fmri is invalid
328 	 *   -1, errno = any else - error
329 	 */
330 	if (rc == 0 || err == EINVAL) {
331 		if (rc == 0)
332 			(void) fmd_agent_seterrno(hdl, 0);
333 		return (FMD_AGENT_RETIRE_DONE);
334 	}
335 	if (err == EAGAIN)
336 		return (FMD_AGENT_RETIRE_ASYNC);
337 
338 	return (FMD_AGENT_RETIRE_FAIL);
339 }
340