xref: /illumos-gate/usr/src/lib/libdiskmgt/common/libdiskmgt.h (revision f85f43ed9f8f93958ca75033d5f390666baa0b6c)
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  * Copyright (c) 2012, Joyent, Inc. All rights reserved.
29  * Copyright 2017 Nexenta Systems, Inc.
30  */
31 
32 #ifndef _LIBDISKMGT_H
33 #define	_LIBDISKMGT_H
34 
35 #ifdef __cplusplus
36 extern "C" {
37 #endif
38 
39 #include <libnvpair.h>
40 #include <sys/swap.h>
41 
42 
43 /*
44  * Disk Management Library
45  *
46  * This library provides a common way to gather information about a system's
47  * disks, controllers, and related components.
48  *
49  *
50  * THREADS
51  * -------
52  *
53  * In general all of the functions are thread safe, however there are some
54  * specific considerations for getting events.  The dm_get_event function may
55  * block the calling thread if no event is currently available.  If another
56  * thread calls dm_get_event while a thread is already blocked in this function,
57  * the second thread will also block.  When an event arrives and multiple
58  * threads are waiting for events, it is undefined which thread will be
59  * unblocked and receive the event.  If a callback is used for handling events,
60  * this is equivalent to the dm_get_event function, so mixing callbacks and
61  * dm_get_event is also nondeterministic.
62  *
63  *
64  * ERRORS
65  * ------
66  *
67  * In general all of the functions take an errno pointer.  This is an integer
68  * that will contain 0 if the function succeeded or contains an errno (see
69  * errno.h) if there was an error.  If the function returns some data, that
70  * return data will generally be null if an error occured (see the API comment
71  * for the specific function for details).  Many of the functions take a
72  * descriptor and provide more information for that descriptor.  These functions
73  * may return an error if the object was removed between the call which obtained
74  * the descriptor and the call to get more information about the object (errno
75  * will be ENODEV).  Only a few of the possible errno values will be returned;
76  * typically:
77  *     EPERM       not super-user
78  *     ENOMEM      not enough memory
79  *     ENODEV      no such device
80  *     EINVAL      invalid argument
81  *     ENOENT      no event queue has been created
82  *
83  * Many of the functions require the application to be running as root in order
84  * to get complete information.  EPERM will be returned if the application is
85  * not running as root.  However, not all of the functions have this requirement
86  * (i.e. event handling).
87  *
88  * It is possible for the system to run out of memory while receiving events.
89  * Since event receipt is asyncronous from the dm_get_event call there may not
90  * be a thread waiting when the event occurs and ENOMEM is detected.  In this
91  * case the event will be lost.  The first call to dm_get_event following this
92  * condition will immediately return ENOMEM, even if events are queued.
93  * Subsequent calls can return events.  The dm_get_event call will clear the
94  * pending ENOMEM condition.  There is no way to know how many events were lost
95  * when this situation occurs.  If a thread is waiting when the event arrives
96  * and the ENOMEM condition occurs, the call will also return with ENOMEM.
97  * There is no way to determine if the system ran out of memory before the
98  * dm_get_event call or while the thread was blocked in the dm_get_event call
99  * since both conditions cause dm_get_event to return ENOMEM.
100  *
101  *
102  * MEMORY MANAGEMENT
103  * -----------------
104  *
105  * Most of the functions that return data are returning memory that has been
106  * allocated and must be freed by the application when no longer needed.  The
107  * application should call the proper free function to free the memory.  Most of
108  * the functions return either a nvlist or an array of descriptors.  The normal
109  * nvlist function (nvlist_free; see libnvpair(3LIB)) can be used to free the
110  * simple nvlists.  Other functions are provided to free the more complex data
111  * structures.
112  *
113  * The following list shows the functions that return allocated memory and the
114  * corresponding function to free the memory:
115  *     dm_get_descriptors            dm_free_descriptors
116  *     dm_get_associated_descriptors dm_free_descriptors
117  *     dm_get_descriptor_by_name     dm_free_descriptor
118  *     dm_get_name                   dm_free_name
119  *     dm_get_attributes             nvlist_free
120  *     dm_get_stats	          nvlist_free
121  *     dm_get_event                  nvlist_free
122  *
123  *
124  * EVENTS
125  * ------
126  *
127  * Event information is returned as a nvlist.  It may be possible to return more
128  * information about events over time, especially information about what has
129  * changed.  However, that may not always be the case, so by using an nvlist we
130  * have a very generic event indication.  At a minimum the event will return the
131  * name of the device, the type of device (see dm_desc_type_t) and the type of
132  * event.  The event type is a string which can currently be; add, remove,
133  * change.
134  *
135  * If a drive goes up or down this could be returned as event type "change".
136  * The application could get the drive information to see that the "status"
137  * attribute has changed value (ideally the event would include an attribute
138  * with the name of the changed attribute as the value).  Although the API can
139  * return events for all drive related changes, events will not necessarily be
140  * delivered for all changes unless the system generates those events.
141  *
142  *
143  * Controller/HBAs
144  * ---------------
145  *
146  * In general the API means "the parent node of the drive in the device tree"
147  * where the word "controller" is used.  This can actually be either the HBA or
148  * the drive controller depending on the type of the drive.
149  *
150  * Drives can be connected to their controller(s) in three different ways:
151  *     single controller
152  *     multiple controllers
153  *     multiple controllers with mpxio
154  * These cases will lead to different information being available for the
155  * configuration.  The two interesting cases are multi-path with and without
156  * mpxio.  With mpxio the drive will have a unique name and a single controller
157  * (scsi_vhci).  The physical controllers, the paths to the drive, can be
158  * obtained by calling dm_get_associated_descriptors with a drive descriptor and
159  * a type of DM_PATH.  This will only return these physical paths when MPXIO, or
160  * possibly some future similar feature, is controlling the drive.
161  *
162  * Without mpxio the drive does not have a unique public name (in all cases the
163  * alias(es) of the drive can be determined by calling
164  * dm_get_associated_descriptors to get the DM_ALIAS descriptors.  There will be
165  * more than one controller returned from dm_get_associated_descriptors when
166  * called with a type of DM_CONTROLLER.  The controllers for each of the aliases
167  * will be returned in the same order as the aliases descriptors.  For example,
168  * a drive with two paths has the aliases c5t3d2 and c7t1d0.  There will be two
169  * controllers returned; the first corresponds to c5 and the second corresponds
170  * to c7.
171  *
172  * In the multi-path, non-mpxio case the drive has more than one alias.
173  * Although most of the drive attributes are represented on the drive (see
174  * dm_get_attributes) there can be some different attributes for the different
175  * aliases for the drive.  Use dm_get_associated_descriptors to get the DM_ALIAS
176  * descriptors which can then be used to obtain these attributes.  Use of this
177  * algorithm is not restricted to the multi-path, non-mpxio case.  For example,
178  * it can be used to get the target/lun for a SCSI drive with a single path.
179  */
180 
181 /*
182  * Holds all the data regarding the device.
183  * Private to libdiskmgt. Must use dm_xxx functions to set/get data.
184  */
185 typedef uint64_t  dm_descriptor_t;
186 
187 typedef enum {
188 	DM_WHO_MKFS = 0,
189 	DM_WHO_ZPOOL,
190 	DM_WHO_ZPOOL_FORCE,
191 	DM_WHO_FORMAT,
192 	DM_WHO_SWAP,
193 	DM_WHO_DUMP,
194 	DM_WHO_ZPOOL_SPARE
195 } dm_who_type_t;
196 
197 /*
198  * The API uses a "descriptor" to identify the managed objects such as drives,
199  * controllers, media, slices, partitions, paths and buses.  The descriptors are
200  * opaque and are only returned or used as parameters to the other functions in
201  * the API.  The descriptor definition is a typedef to dm_descriptor_t.
202  *
203  * Applications call either the dm_get_descriptors or
204  * dm_get_associated_descriptors function to obtain a list of descriptors of a
205  * specific type.  The application specifies the desired type from the following
206  * enumeration:
207  */
208 typedef enum {
209     DM_DRIVE = 0,
210     DM_CONTROLLER,
211     DM_MEDIA,
212     DM_SLICE,
213     DM_PARTITION,
214     DM_PATH,
215     DM_ALIAS,
216     DM_BUS
217 } dm_desc_type_t;
218 
219 /*
220  * These descriptors are associated with each other in the following way:
221  *
222  *                      alias                 partition
223  *     _                    \                /   |
224  *    / \                    \              /    |
225  *    \ /                     \            /     |
226  *    bus --- controller --- drive --- media     |
227  *                     |      /            \     |
228  *                     |     /              \    |
229  *                     |    /                \   |
230  *                      path                  slice
231  *
232  * The dm_get_associated_descriptors function can be used get the descriptors
233  * associated with a given descriptor.  The dm_get_associated_types function can
234  * be used to find the types that can be associated with a given type.
235  *
236  * The attributes and values for these objects are described using a list of
237  * name/value pairs (see libnvpair(3LIB) and the specific comments for each
238  * function in the API section of this document).
239  *
240  * Drives and media have a type which are defined as the following enumerations.
241  * There could be additional types added to these enumerations as new drive and
242  * media types are supported by the system.
243  */
244 
245 typedef enum {
246     DM_DT_UNKNOWN = 0,
247     DM_DT_FIXED,
248     DM_DT_ZIP,
249     DM_DT_JAZ,
250     DM_DT_FLOPPY,
251     DM_DT_MO_ERASABLE,
252     DM_DT_MO_WRITEONCE,
253     DM_DT_AS_MO,
254     DM_DT_CDROM,
255     DM_DT_CDR,
256     DM_DT_CDRW,
257     DM_DT_DVDROM,
258     DM_DT_DVDR,
259     DM_DT_DVDRAM,
260     DM_DT_DVDRW,
261     DM_DT_DDCDROM,
262     DM_DT_DDCDR,
263     DM_DT_DDCDRW
264 } dm_drive_type_t;
265 
266 typedef enum {
267     DM_MT_UNKNOWN = 0,
268     DM_MT_FIXED,
269     DM_MT_FLOPPY,
270     DM_MT_CDROM,
271     DM_MT_ZIP,
272     DM_MT_JAZ,
273     DM_MT_CDR,
274     DM_MT_CDRW,
275     DM_MT_DVDROM,
276     DM_MT_DVDR,
277     DM_MT_DVDRAM,
278     DM_MT_MO_ERASABLE,
279     DM_MT_MO_WRITEONCE,
280     DM_MT_AS_MO
281 } dm_media_type_t;
282 
283 #define	DM_FILTER_END	-1
284 
285 /*
286  * The dm_get_stats function takes a stat_type argument for the specific sample
287  * to get for the descriptor.  The following enums specify the drive and slice
288  * stat types.
289  */
290 /* drive stat name */
291 typedef enum {
292     DM_DRV_STAT_PERFORMANCE = 0,
293     DM_DRV_STAT_DIAGNOSTIC,
294     DM_DRV_STAT_TEMPERATURE
295 } dm_drive_stat_t;
296 
297 /* slice stat name */
298 typedef enum {
299     DM_SLICE_STAT_USE = 0
300 } dm_slice_stat_t;
301 
302 /* partition type */
303 typedef enum {
304 	DM_PRIMARY = 0,
305 	DM_EXTENDED,
306 	DM_LOGICAL
307 } dm_partition_type_t;
308 
309 /* attribute definitions */
310 
311 /* drive */
312 #define	DM_DISK_UP		1
313 #define	DM_DISK_DOWN		0
314 
315 #define	DM_DRVTYPE		"drvtype"
316 #define	DM_FAILING		"failing"
317 #define	DM_LOADED		"loaded"	/* also in media */
318 #define	DM_NDNRERRS		"ndevice_not_ready_errors"
319 #define	DM_NBYTESREAD		"nbytes_read"
320 #define	DM_NBYTESWRITTEN	"nbytes_written"
321 #define	DM_NHARDERRS		"nhard_errors"
322 #define	DM_NILLREQERRS		"nillegal_req_errors"
323 #define	DM_NMEDIAERRS		"nmedia_errors"
324 #define	DM_NNODEVERRS		"nno_dev_errors"
325 #define	DM_NREADOPS		"nread_ops"
326 #define	DM_NRECOVERRS		"nrecoverable_errors"
327 #define	DM_NSOFTERRS		"nsoft_errors"
328 #define	DM_NTRANSERRS		"ntransport_errors"
329 #define	DM_NWRITEOPS		"nwrite_ops"
330 #define	DM_OPATH		"opath"
331 #define	DM_PRODUCT_ID		"product_id"
332 #define	DM_REMOVABLE		"removable"	/* also in media */
333 #define	DM_RPM			"rpm"
334 #define	DM_SOLIDSTATE		"solid_state"
335 #define	DM_STATUS		"status"
336 #define	DM_SYNC_SPEED		"sync_speed"
337 #define	DM_TEMPERATURE		"temperature"
338 #define	DM_VENDOR_ID		"vendor_id"
339 #define	DM_WIDE			"wide"		/* also on controller */
340 #define	DM_WWN			"wwn"
341 
342 /* bus */
343 #define	DM_BTYPE		"btype"
344 #define	DM_CLOCK		"clock"		/* also on controller */
345 #define	DM_PNAME		"pname"
346 
347 /* controller */
348 #define	DM_FAST			"fast"
349 #define	DM_FAST20		"fast20"
350 #define	DM_FAST40		"fast40"
351 #define	DM_FAST80		"fast80"
352 #define	DM_MULTIPLEX		"multiplex"
353 #define	DM_PATH_STATE		"path_state"
354 
355 #define	DM_CTYPE_ATA		"ata"
356 #define	DM_CTYPE_FIBRE		"fibre"
357 #define	DM_CTYPE_LOFI		"lofi"
358 #define	DM_CTYPE_NVME		"nvme"
359 #define	DM_CTYPE_SATA		"sata"
360 #define	DM_CTYPE_SCSI		"scsi"
361 #define	DM_CTYPE_USB		"usb"
362 #define	DM_CTYPE_XEN		"xen"
363 #define	DM_CTYPE_UNKNOWN	"unknown"
364 
365 /* media */
366 #define	DM_BLOCKSIZE		"blocksize"
367 #define	DM_FDISK		"fdisk"
368 #define	DM_MTYPE		"mtype"
369 #define	DM_NACTUALCYLINDERS	"nactual_cylinders"
370 #define	DM_NALTCYLINDERS	"nalt_cylinders"
371 #define	DM_NCYLINDERS		"ncylinders"
372 #define	DM_NHEADS		"nheads"
373 #define	DM_NPHYSCYLINDERS	"nphys_cylinders"
374 #define	DM_NSECTORS		"nsectors"	/* also in partition */
375 #define	DM_SIZE			"size"		/* also in slice */
376 #define	DM_NACCESSIBLE		"naccessible"
377 #define	DM_LABEL		"label"
378 
379 /* partition */
380 #define	DM_BCYL			"bcyl"
381 #define	DM_BHEAD		"bhead"
382 #define	DM_BOOTID		"bootid"
383 #define	DM_BSECT		"bsect"
384 #define	DM_ECYL			"ecyl"
385 #define	DM_EHEAD		"ehead"
386 #define	DM_ESECT		"esect"
387 #define	DM_PTYPE		"ptype" /* this references the partition id */
388 #define	DM_PARTITION_TYPE	"part_type" /* primary, extended, logical */
389 #define	DM_RELSECT		"relsect"
390 
391 /* slice */
392 #define	DM_DEVICEID		"deviceid"
393 #define	DM_DEVT			"devt"
394 #define	DM_INDEX		"index"
395 #define	DM_EFI_NAME		"name"
396 #define	DM_MOUNTPOINT		"mountpoint"
397 #define	DM_LOCALNAME		"localname"
398 #define	DM_START		"start"
399 #define	DM_TAG			"tag"
400 #define	DM_FLAG			"flag"
401 #define	DM_EFI			"efi"	/* also on media */
402 #define	DM_USED_BY		"used_by"
403 #define	DM_USED_NAME		"used_name"
404 #define	DM_USE_MOUNT		"mount"
405 #define	DM_USE_LU		"lu"
406 #define	DM_USE_DUMP		"dump"
407 #define	DM_USE_VXVM		"vxvm"
408 #define	DM_USE_FS		"fs"
409 #define	DM_USE_VFSTAB		"vfstab"
410 #define	DM_USE_EXPORTED_ZPOOL	"exported_zpool"
411 #define	DM_USE_ACTIVE_ZPOOL	"active_zpool"
412 #define	DM_USE_SPARE_ZPOOL	"spare_zpool"
413 #define	DM_USE_L2CACHE_ZPOOL	"l2cache_zpool"
414 
415 /* event */
416 #define	DM_EV_NAME		"name"
417 #define	DM_EV_DTYPE		"edtype"
418 #define	DM_EV_TYPE		"evtype"
419 #define	DM_EV_TADD		"add"
420 #define	DM_EV_TREMOVE		"remove"
421 #define	DM_EV_TCHANGE		"change"
422 
423 /* findisks */
424 #define	DM_CTYPE		"ctype"
425 #define	DM_LUN			"lun"
426 #define	DM_TARGET		"target"
427 
428 #define	NOINUSE_SET	getenv("NOINUSE_CHECK") != NULL
429 
430 void			dm_free_descriptors(dm_descriptor_t *desc_list);
431 void			dm_free_descriptor(dm_descriptor_t desc);
432 void			dm_free_name(char *name);
433 void			dm_free_swapentries(swaptbl_t *);
434 
435 dm_descriptor_t		*dm_get_descriptors(dm_desc_type_t type, int filter[],
436 			    int *errp);
437 dm_descriptor_t		*dm_get_associated_descriptors(dm_descriptor_t desc,
438 			    dm_desc_type_t type, int *errp);
439 dm_desc_type_t		*dm_get_associated_types(dm_desc_type_t type);
440 dm_descriptor_t		dm_get_descriptor_by_name(dm_desc_type_t desc_type,
441 			    char *name, int *errp);
442 char			*dm_get_name(dm_descriptor_t desc, int *errp);
443 dm_desc_type_t		dm_get_type(dm_descriptor_t desc);
444 nvlist_t		*dm_get_attributes(dm_descriptor_t desc, int *errp);
445 nvlist_t		*dm_get_stats(dm_descriptor_t desc, int stat_type,
446 			    int *errp);
447 void			dm_init_event_queue(void(*callback)(nvlist_t *, int),
448 			    int *errp);
449 nvlist_t		*dm_get_event(int *errp);
450 void			dm_get_slices(char *drive, dm_descriptor_t **slices,
451 			    int *errp);
452 void			dm_get_slice_stats(char *slice, nvlist_t **dev_stats,
453 			    int *errp);
454 int			dm_get_swapentries(swaptbl_t **, int *);
455 void			dm_get_usage_string(char *who, char *data, char **msg);
456 int			dm_inuse(char *dev_name, char **msg, dm_who_type_t who,
457 			    int *errp);
458 int			dm_inuse_swap(const char *dev_name, int *errp);
459 int			dm_isoverlapping(char *dev_name, char **msg, int *errp);
460 
461 #ifdef __cplusplus
462 }
463 #endif
464 
465 #endif /* _LIBDISKMGT_H */
466