xref: /freebsd/sys/contrib/openzfs/lib/libzfs/os/linux/libzfs_pool_os.c (revision aca928a50a42f00f344df934005b09dbcb4e2f77)
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 https://opensource.org/licenses/CDDL-1.0.
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 2015 Nexenta Systems, Inc.  All rights reserved.
24  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
25  * Copyright (c) 2011, 2018 by Delphix. All rights reserved.
26  * Copyright 2016 Igor Kozhukhov <ikozhukhov@gmail.com>
27  * Copyright (c) 2018 Datto Inc.
28  * Copyright (c) 2017 Open-E, Inc. All Rights Reserved.
29  * Copyright (c) 2017, Intel Corporation.
30  * Copyright (c) 2018, loli10K <ezomori.nozomu@gmail.com>
31  */
32 
33 #include <errno.h>
34 #include <libintl.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 #include <libgen.h>
40 #include <zone.h>
41 #include <sys/stat.h>
42 #include <sys/efi_partition.h>
43 #include <sys/systeminfo.h>
44 #include <sys/zfs_ioctl.h>
45 #include <sys/vdev_disk.h>
46 #include <dlfcn.h>
47 #include <libzutil.h>
48 
49 #include "zfs_namecheck.h"
50 #include "zfs_prop.h"
51 #include "../../libzfs_impl.h"
52 #include "zfs_comutil.h"
53 #include "zfeature_common.h"
54 
55 /*
56  * If the device has being dynamically expanded then we need to relabel
57  * the disk to use the new unallocated space.
58  */
59 int
zpool_relabel_disk(libzfs_handle_t * hdl,const char * path,const char * msg)60 zpool_relabel_disk(libzfs_handle_t *hdl, const char *path, const char *msg)
61 {
62 	int fd, error;
63 
64 	if ((fd = open(path, O_RDWR|O_DIRECT|O_CLOEXEC)) < 0) {
65 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "cannot "
66 		    "relabel '%s': unable to open device: %d"), path, errno);
67 		return (zfs_error(hdl, EZFS_OPENFAILED, msg));
68 	}
69 
70 	/*
71 	 * It's possible that we might encounter an error if the device
72 	 * does not have any unallocated space left. If so, we simply
73 	 * ignore that error and continue on.
74 	 */
75 	error = efi_use_whole_disk(fd);
76 
77 	/* Flush the buffers to disk and invalidate the page cache. */
78 	(void) fsync(fd);
79 	(void) ioctl(fd, BLKFLSBUF);
80 
81 	(void) close(fd);
82 	if (error && error != VT_ENOSPC) {
83 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "cannot "
84 		    "relabel '%s': unable to read disk capacity"), path);
85 		return (zfs_error(hdl, EZFS_NOCAP, msg));
86 	}
87 	return (0);
88 }
89 
90 /*
91  * Read the EFI label from the config, if a label does not exist then
92  * pass back the error to the caller. If the caller has passed a non-NULL
93  * diskaddr argument then we set it to the starting address of the EFI
94  * partition.
95  */
96 static int
read_efi_label(nvlist_t * config,diskaddr_t * sb)97 read_efi_label(nvlist_t *config, diskaddr_t *sb)
98 {
99 	const char *path;
100 	int fd;
101 	char diskname[MAXPATHLEN];
102 	int err = -1;
103 
104 	if (nvlist_lookup_string(config, ZPOOL_CONFIG_PATH, &path) != 0)
105 		return (err);
106 
107 	(void) snprintf(diskname, sizeof (diskname), "%s%s", DISK_ROOT,
108 	    strrchr(path, '/'));
109 	if ((fd = open(diskname, O_RDONLY|O_DIRECT|O_CLOEXEC)) >= 0) {
110 		struct dk_gpt *vtoc;
111 
112 		if ((err = efi_alloc_and_read(fd, &vtoc)) >= 0) {
113 			if (sb != NULL)
114 				*sb = vtoc->efi_parts[0].p_start;
115 			efi_free(vtoc);
116 		}
117 		(void) close(fd);
118 	}
119 	return (err);
120 }
121 
122 /*
123  * determine where a partition starts on a disk in the current
124  * configuration
125  */
126 static diskaddr_t
find_start_block(nvlist_t * config)127 find_start_block(nvlist_t *config)
128 {
129 	nvlist_t **child;
130 	uint_t c, children;
131 	diskaddr_t sb = MAXOFFSET_T;
132 	uint64_t wholedisk;
133 
134 	if (nvlist_lookup_nvlist_array(config,
135 	    ZPOOL_CONFIG_CHILDREN, &child, &children) != 0) {
136 		if (nvlist_lookup_uint64(config,
137 		    ZPOOL_CONFIG_WHOLE_DISK,
138 		    &wholedisk) != 0 || !wholedisk) {
139 			return (MAXOFFSET_T);
140 		}
141 		if (read_efi_label(config, &sb) < 0)
142 			sb = MAXOFFSET_T;
143 		return (sb);
144 	}
145 
146 	for (c = 0; c < children; c++) {
147 		sb = find_start_block(child[c]);
148 		if (sb != MAXOFFSET_T) {
149 			return (sb);
150 		}
151 	}
152 	return (MAXOFFSET_T);
153 }
154 
155 static int
zpool_label_disk_check(char * path)156 zpool_label_disk_check(char *path)
157 {
158 	struct dk_gpt *vtoc;
159 	int fd, err;
160 
161 	if ((fd = open(path, O_RDONLY|O_DIRECT|O_CLOEXEC)) < 0)
162 		return (errno);
163 
164 	if ((err = efi_alloc_and_read(fd, &vtoc)) != 0) {
165 		(void) close(fd);
166 		return (err);
167 	}
168 
169 	if (vtoc->efi_flags & EFI_GPT_PRIMARY_CORRUPT) {
170 		efi_free(vtoc);
171 		(void) close(fd);
172 		return (EIDRM);
173 	}
174 
175 	efi_free(vtoc);
176 	(void) close(fd);
177 	return (0);
178 }
179 
180 /*
181  * Generate a unique partition name for the ZFS member.  Partitions must
182  * have unique names to ensure udev will be able to create symlinks under
183  * /dev/disk/by-partlabel/ for all pool members.  The partition names are
184  * of the form <pool>-<unique-id>.
185  */
186 static void
zpool_label_name(char * label_name,int label_size)187 zpool_label_name(char *label_name, int label_size)
188 {
189 	uint64_t id = 0;
190 	int fd;
191 
192 	fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC);
193 	if (fd >= 0) {
194 		if (read(fd, &id, sizeof (id)) != sizeof (id))
195 			id = 0;
196 
197 		close(fd);
198 	}
199 
200 	if (id == 0)
201 		id = (((uint64_t)rand()) << 32) | (uint64_t)rand();
202 
203 	snprintf(label_name, label_size, "zfs-%016llx", (u_longlong_t)id);
204 }
205 
206 /*
207  * Label an individual disk.  The name provided is the short name,
208  * stripped of any leading /dev path.
209  */
210 int
zpool_label_disk(libzfs_handle_t * hdl,zpool_handle_t * zhp,const char * name)211 zpool_label_disk(libzfs_handle_t *hdl, zpool_handle_t *zhp, const char *name)
212 {
213 	char path[MAXPATHLEN];
214 	struct dk_gpt *vtoc;
215 	int rval, fd;
216 	size_t resv = EFI_MIN_RESV_SIZE;
217 	uint64_t slice_size;
218 	diskaddr_t start_block;
219 	char errbuf[ERRBUFLEN];
220 
221 	/* prepare an error message just in case */
222 	(void) snprintf(errbuf, sizeof (errbuf),
223 	    dgettext(TEXT_DOMAIN, "cannot label '%s'"), name);
224 
225 	if (zhp) {
226 		nvlist_t *nvroot = fnvlist_lookup_nvlist(zhp->zpool_config,
227 		    ZPOOL_CONFIG_VDEV_TREE);
228 
229 		if (zhp->zpool_start_block == 0)
230 			start_block = find_start_block(nvroot);
231 		else
232 			start_block = zhp->zpool_start_block;
233 		zhp->zpool_start_block = start_block;
234 	} else {
235 		/* new pool */
236 		start_block = NEW_START_BLOCK;
237 	}
238 
239 	(void) snprintf(path, sizeof (path), "%s/%s", DISK_ROOT, name);
240 
241 	if ((fd = open(path, O_RDWR|O_DIRECT|O_EXCL|O_CLOEXEC)) < 0) {
242 		/*
243 		 * This shouldn't happen.  We've long since verified that this
244 		 * is a valid device.
245 		 */
246 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "cannot "
247 		    "label '%s': unable to open device: %d"), path, errno);
248 		return (zfs_error(hdl, EZFS_OPENFAILED, errbuf));
249 	}
250 
251 	if (efi_alloc_and_init(fd, EFI_NUMPAR, &vtoc) != 0) {
252 		/*
253 		 * The only way this can fail is if we run out of memory, or we
254 		 * were unable to read the disk's capacity
255 		 */
256 		if (errno == ENOMEM)
257 			(void) no_memory(hdl);
258 
259 		(void) close(fd);
260 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "cannot "
261 		    "label '%s': unable to read disk capacity"), path);
262 
263 		return (zfs_error(hdl, EZFS_NOCAP, errbuf));
264 	}
265 
266 	slice_size = vtoc->efi_last_u_lba + 1;
267 	slice_size -= EFI_MIN_RESV_SIZE;
268 	if (start_block == MAXOFFSET_T)
269 		start_block = NEW_START_BLOCK;
270 	slice_size -= start_block;
271 	slice_size = P2ALIGN_TYPED(slice_size, PARTITION_END_ALIGNMENT,
272 	    uint64_t);
273 
274 	vtoc->efi_parts[0].p_start = start_block;
275 	vtoc->efi_parts[0].p_size = slice_size;
276 
277 	if (vtoc->efi_parts[0].p_size * vtoc->efi_lbasize < SPA_MINDEVSIZE) {
278 		(void) close(fd);
279 		efi_free(vtoc);
280 
281 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "cannot "
282 		    "label '%s': partition would be less than the minimum "
283 		    "device size (64M)"), path);
284 		return (zfs_error(hdl, EZFS_LABELFAILED, errbuf));
285 	}
286 
287 	/*
288 	 * Why we use V_USR: V_BACKUP confuses users, and is considered
289 	 * disposable by some EFI utilities (since EFI doesn't have a backup
290 	 * slice).  V_UNASSIGNED is supposed to be used only for zero size
291 	 * partitions, and efi_write() will fail if we use it.
292 	 * Other available types were all pretty specific.
293 	 * V_USR is as close to reality as we
294 	 * can get, in the absence of V_OTHER.
295 	 */
296 	vtoc->efi_parts[0].p_tag = V_USR;
297 	zpool_label_name(vtoc->efi_parts[0].p_name, EFI_PART_NAME_LEN);
298 
299 	vtoc->efi_parts[8].p_start = slice_size + start_block;
300 	vtoc->efi_parts[8].p_size = resv;
301 	vtoc->efi_parts[8].p_tag = V_RESERVED;
302 
303 	rval = efi_write(fd, vtoc);
304 
305 	/* Flush the buffers to disk and invalidate the page cache. */
306 	(void) fsync(fd);
307 	(void) ioctl(fd, BLKFLSBUF);
308 
309 	if (rval == 0)
310 		rval = efi_rescan(fd);
311 
312 	/*
313 	 * Some block drivers (like pcata) may not support EFI GPT labels.
314 	 * Print out a helpful error message directing the user to manually
315 	 * label the disk and give a specific slice.
316 	 */
317 	if (rval != 0) {
318 		(void) close(fd);
319 		efi_free(vtoc);
320 
321 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "try using "
322 		    "parted(8) and then provide a specific slice: %d"), rval);
323 		return (zfs_error(hdl, EZFS_LABELFAILED, errbuf));
324 	}
325 
326 	(void) close(fd);
327 	efi_free(vtoc);
328 
329 	(void) snprintf(path, sizeof (path), "%s/%s", DISK_ROOT, name);
330 	(void) zfs_append_partition(path, MAXPATHLEN);
331 
332 	/* Wait to udev to signal use the device has settled. */
333 	rval = zpool_label_disk_wait(path, DISK_LABEL_WAIT);
334 	if (rval) {
335 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "failed to "
336 		    "detect device partitions on '%s': %d"), path, rval);
337 		return (zfs_error(hdl, EZFS_LABELFAILED, errbuf));
338 	}
339 
340 	/* We can't be to paranoid.  Read the label back and verify it. */
341 	(void) snprintf(path, sizeof (path), "%s/%s", DISK_ROOT, name);
342 	rval = zpool_label_disk_check(path);
343 	if (rval) {
344 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "freshly written "
345 		    "EFI label on '%s' is damaged.  Ensure\nthis device "
346 		    "is not in use, and is functioning properly: %d"),
347 		    path, rval);
348 		return (zfs_error(hdl, EZFS_LABELFAILED, errbuf));
349 	}
350 	return (0);
351 }
352