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  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2012, 2020 by Delphix. All rights reserved.
24  * Copyright 2016 RackTop Systems.
25  * Copyright (c) 2017, Intel Corporation.
26  */
27 
28 #ifndef	_SYS_ZFS_IOCTL_H
29 #define	_SYS_ZFS_IOCTL_H
30 
31 #include <sys/cred.h>
32 #include <sys/dmu.h>
33 #include <sys/zio.h>
34 #include <sys/dsl_deleg.h>
35 #include <sys/spa.h>
36 #include <sys/zfs_stat.h>
37 
38 #ifdef _KERNEL
39 #include <sys/nvpair.h>
40 #endif	/* _KERNEL */
41 
42 #ifdef	__cplusplus
43 extern "C" {
44 #endif
45 
46 /*
47  * The structures in this file are passed between userland and the
48  * kernel.  Userland may be running a 32-bit process, while the kernel
49  * is 64-bit.  Therefore, these structures need to compile the same in
50  * 32-bit and 64-bit.  This means not using type "long", and adding
51  * explicit padding so that the 32-bit structure will not be packed more
52  * tightly than the 64-bit structure (which requires 64-bit alignment).
53  */
54 
55 /*
56  * Property values for snapdir
57  */
58 #define	ZFS_SNAPDIR_HIDDEN		0
59 #define	ZFS_SNAPDIR_VISIBLE		1
60 
61 /*
62  * Property values for snapdev
63  */
64 #define	ZFS_SNAPDEV_HIDDEN		0
65 #define	ZFS_SNAPDEV_VISIBLE		1
66 /*
67  * Property values for acltype
68  */
69 #define	ZFS_ACLTYPE_OFF			0
70 #define	ZFS_ACLTYPE_POSIX		1
71 #define	ZFS_ACLTYPE_NFSV4		2
72 
73 /*
74  * Field manipulation macros for the drr_versioninfo field of the
75  * send stream header.
76  */
77 
78 /*
79  * Header types for zfs send streams.
80  */
81 typedef enum drr_headertype {
82 	DMU_SUBSTREAM = 0x1,
83 	DMU_COMPOUNDSTREAM = 0x2
84 } drr_headertype_t;
85 
86 #define	DMU_GET_STREAM_HDRTYPE(vi)	BF64_GET((vi), 0, 2)
87 #define	DMU_SET_STREAM_HDRTYPE(vi, x)	BF64_SET((vi), 0, 2, x)
88 
89 #define	DMU_GET_FEATUREFLAGS(vi)	BF64_GET((vi), 2, 30)
90 #define	DMU_SET_FEATUREFLAGS(vi, x)	BF64_SET((vi), 2, 30, x)
91 
92 /*
93  * Feature flags for zfs send streams (flags in drr_versioninfo)
94  */
95 
96 #define	DMU_BACKUP_FEATURE_DEDUP		(1 << 0)
97 #define	DMU_BACKUP_FEATURE_DEDUPPROPS		(1 << 1)
98 #define	DMU_BACKUP_FEATURE_SA_SPILL		(1 << 2)
99 /* flags #3 - #15 are reserved for incompatible closed-source implementations */
100 #define	DMU_BACKUP_FEATURE_EMBED_DATA		(1 << 16)
101 #define	DMU_BACKUP_FEATURE_LZ4			(1 << 17)
102 /* flag #18 is reserved for a Delphix feature */
103 #define	DMU_BACKUP_FEATURE_LARGE_BLOCKS		(1 << 19)
104 #define	DMU_BACKUP_FEATURE_RESUMING		(1 << 20)
105 #define	DMU_BACKUP_FEATURE_REDACTED		(1 << 21)
106 #define	DMU_BACKUP_FEATURE_COMPRESSED		(1 << 22)
107 #define	DMU_BACKUP_FEATURE_LARGE_DNODE		(1 << 23)
108 #define	DMU_BACKUP_FEATURE_RAW			(1 << 24)
109 #define	DMU_BACKUP_FEATURE_ZSTD			(1 << 25)
110 #define	DMU_BACKUP_FEATURE_HOLDS		(1 << 26)
111 /*
112  * The SWITCH_TO_LARGE_BLOCKS feature indicates that we can receive
113  * incremental LARGE_BLOCKS streams (those with WRITE records of >128KB) even
114  * if the previous send did not use LARGE_BLOCKS, and thus its large blocks
115  * were split into multiple 128KB WRITE records.  (See
116  * flush_write_batch_impl() and receive_object()).  Older software that does
117  * not support this flag may encounter a bug when switching to large blocks,
118  * which causes files to incorrectly be zeroed.
119  *
120  * This flag is currently not set on any send streams.  In the future, we
121  * intend for incremental send streams of snapshots that have large blocks to
122  * use LARGE_BLOCKS by default, and these streams will also have the
123  * SWITCH_TO_LARGE_BLOCKS feature set. This ensures that streams from the
124  * default use of "zfs send" won't encounter the bug mentioned above.
125  */
126 #define	DMU_BACKUP_FEATURE_SWITCH_TO_LARGE_BLOCKS (1 << 27)
127 
128 /*
129  * Mask of all supported backup features
130  */
131 #define	DMU_BACKUP_FEATURE_MASK	(DMU_BACKUP_FEATURE_SA_SPILL | \
132     DMU_BACKUP_FEATURE_EMBED_DATA | DMU_BACKUP_FEATURE_LZ4 | \
133     DMU_BACKUP_FEATURE_RESUMING | DMU_BACKUP_FEATURE_LARGE_BLOCKS | \
134     DMU_BACKUP_FEATURE_COMPRESSED | DMU_BACKUP_FEATURE_LARGE_DNODE | \
135     DMU_BACKUP_FEATURE_RAW | DMU_BACKUP_FEATURE_HOLDS | \
136     DMU_BACKUP_FEATURE_REDACTED | DMU_BACKUP_FEATURE_SWITCH_TO_LARGE_BLOCKS | \
137     DMU_BACKUP_FEATURE_ZSTD)
138 
139 /* Are all features in the given flag word currently supported? */
140 #define	DMU_STREAM_SUPPORTED(x)	(!((x) & ~DMU_BACKUP_FEATURE_MASK))
141 
142 typedef enum dmu_send_resume_token_version {
143 	ZFS_SEND_RESUME_TOKEN_VERSION = 1
144 } dmu_send_resume_token_version_t;
145 
146 /*
147  * The drr_versioninfo field of the dmu_replay_record has the
148  * following layout:
149  *
150  *	64	56	48	40	32	24	16	8	0
151  *	+-------+-------+-------+-------+-------+-------+-------+-------+
152  *	|		reserved	|        feature-flags	    |C|S|
153  *	+-------+-------+-------+-------+-------+-------+-------+-------+
154  *
155  * The low order two bits indicate the header type: SUBSTREAM (0x1)
156  * or COMPOUNDSTREAM (0x2).  Using two bits for this is historical:
157  * this field used to be a version number, where the two version types
158  * were 1 and 2.  Using two bits for this allows earlier versions of
159  * the code to be able to recognize send streams that don't use any
160  * of the features indicated by feature flags.
161  */
162 
163 #define	DMU_BACKUP_MAGIC 0x2F5bacbacULL
164 
165 /*
166  * Send stream flags.  Bits 24-31 are reserved for vendor-specific
167  * implementations and should not be used.
168  */
169 #define	DRR_FLAG_CLONE		(1<<0)
170 #define	DRR_FLAG_CI_DATA	(1<<1)
171 /*
172  * This send stream, if it is a full send, includes the FREE and FREEOBJECT
173  * records that are created by the sending process.  This means that the send
174  * stream can be received as a clone, even though it is not an incremental.
175  * This is not implemented as a feature flag, because the receiving side does
176  * not need to have implemented it to receive this stream; it is fully backwards
177  * compatible.  We need a flag, though, because full send streams without it
178  * cannot necessarily be received as a clone correctly.
179  */
180 #define	DRR_FLAG_FREERECORDS	(1<<2)
181 /*
182  * When DRR_FLAG_SPILL_BLOCK is set it indicates the DRR_OBJECT_SPILL
183  * and DRR_SPILL_UNMODIFIED flags are meaningful in the send stream.
184  *
185  * When DRR_FLAG_SPILL_BLOCK is set, DRR_OBJECT records will have
186  * DRR_OBJECT_SPILL set if and only if they should have a spill block
187  * (either an existing one, or a new one in the send stream).  When clear
188  * the object does not have a spill block and any existing spill block
189  * should be freed.
190  *
191  * Similarly, when DRR_FLAG_SPILL_BLOCK is set, DRR_SPILL records will
192  * have DRR_SPILL_UNMODIFIED set if and only if they were included for
193  * backward compatibility purposes, and can be safely ignored by new versions
194  * of zfs receive.  Previous versions of ZFS which do not understand the
195  * DRR_FLAG_SPILL_BLOCK will process this record and recreate any missing
196  * spill blocks.
197  */
198 #define	DRR_FLAG_SPILL_BLOCK	(1<<3)
199 
200 /*
201  * flags in the drr_flags field in the DRR_WRITE, DRR_SPILL, DRR_OBJECT,
202  * DRR_WRITE_BYREF, and DRR_OBJECT_RANGE blocks
203  */
204 #define	DRR_CHECKSUM_DEDUP	(1<<0) /* not used for SPILL records */
205 #define	DRR_RAW_BYTESWAP	(1<<1)
206 #define	DRR_OBJECT_SPILL	(1<<2) /* OBJECT record has a spill block */
207 #define	DRR_SPILL_UNMODIFIED	(1<<2) /* SPILL record for unmodified block */
208 
209 #define	DRR_IS_DEDUP_CAPABLE(flags)	((flags) & DRR_CHECKSUM_DEDUP)
210 #define	DRR_IS_RAW_BYTESWAPPED(flags)	((flags) & DRR_RAW_BYTESWAP)
211 #define	DRR_OBJECT_HAS_SPILL(flags)	((flags) & DRR_OBJECT_SPILL)
212 #define	DRR_SPILL_IS_UNMODIFIED(flags)	((flags) & DRR_SPILL_UNMODIFIED)
213 
214 /* deal with compressed drr_write replay records */
215 #define	DRR_WRITE_COMPRESSED(drrw)	((drrw)->drr_compressiontype != 0)
216 #define	DRR_WRITE_PAYLOAD_SIZE(drrw) \
217 	(DRR_WRITE_COMPRESSED(drrw) ? (drrw)->drr_compressed_size : \
218 	(drrw)->drr_logical_size)
219 #define	DRR_SPILL_PAYLOAD_SIZE(drrs) \
220 	((drrs)->drr_compressed_size ? \
221 	(drrs)->drr_compressed_size : (drrs)->drr_length)
222 #define	DRR_OBJECT_PAYLOAD_SIZE(drro) \
223 	((drro)->drr_raw_bonuslen != 0 ? \
224 	(drro)->drr_raw_bonuslen : P2ROUNDUP((drro)->drr_bonuslen, 8))
225 
226 /*
227  * zfs ioctl command structure
228  */
229 
230 /* Header is used in C++ so can't forward declare untagged struct */
231 struct drr_begin {
232 	uint64_t drr_magic;
233 	uint64_t drr_versioninfo; /* was drr_version */
234 	uint64_t drr_creation_time;
235 	dmu_objset_type_t drr_type;
236 	uint32_t drr_flags;
237 	uint64_t drr_toguid;
238 	uint64_t drr_fromguid;
239 	char drr_toname[MAXNAMELEN];
240 };
241 
242 typedef struct dmu_replay_record {
243 	enum {
244 		DRR_BEGIN, DRR_OBJECT, DRR_FREEOBJECTS,
245 		DRR_WRITE, DRR_FREE, DRR_END, DRR_WRITE_BYREF,
246 		DRR_SPILL, DRR_WRITE_EMBEDDED, DRR_OBJECT_RANGE, DRR_REDACT,
247 		DRR_NUMTYPES
248 	} drr_type;
249 	uint32_t drr_payloadlen;
250 	union {
251 		struct drr_begin drr_begin;
252 		struct drr_end {
253 			zio_cksum_t drr_checksum;
254 			uint64_t drr_toguid;
255 		} drr_end;
256 		struct drr_object {
257 			uint64_t drr_object;
258 			dmu_object_type_t drr_type;
259 			dmu_object_type_t drr_bonustype;
260 			uint32_t drr_blksz;
261 			uint32_t drr_bonuslen;
262 			uint8_t drr_checksumtype;
263 			uint8_t drr_compress;
264 			uint8_t drr_dn_slots;
265 			uint8_t drr_flags;
266 			uint32_t drr_raw_bonuslen;
267 			uint64_t drr_toguid;
268 			/* only (possibly) nonzero for raw streams */
269 			uint8_t drr_indblkshift;
270 			uint8_t drr_nlevels;
271 			uint8_t drr_nblkptr;
272 			uint8_t drr_pad[5];
273 			uint64_t drr_maxblkid;
274 			/* bonus content follows */
275 		} drr_object;
276 		struct drr_freeobjects {
277 			uint64_t drr_firstobj;
278 			uint64_t drr_numobjs;
279 			uint64_t drr_toguid;
280 		} drr_freeobjects;
281 		struct drr_write {
282 			uint64_t drr_object;
283 			dmu_object_type_t drr_type;
284 			uint32_t drr_pad;
285 			uint64_t drr_offset;
286 			uint64_t drr_logical_size;
287 			uint64_t drr_toguid;
288 			uint8_t drr_checksumtype;
289 			uint8_t drr_flags;
290 			uint8_t drr_compressiontype;
291 			uint8_t drr_pad2[5];
292 			/* deduplication key */
293 			ddt_key_t drr_key;
294 			/* only nonzero if drr_compressiontype is not 0 */
295 			uint64_t drr_compressed_size;
296 			/* only nonzero for raw streams */
297 			uint8_t drr_salt[ZIO_DATA_SALT_LEN];
298 			uint8_t drr_iv[ZIO_DATA_IV_LEN];
299 			uint8_t drr_mac[ZIO_DATA_MAC_LEN];
300 			/* content follows */
301 		} drr_write;
302 		struct drr_free {
303 			uint64_t drr_object;
304 			uint64_t drr_offset;
305 			uint64_t drr_length;
306 			uint64_t drr_toguid;
307 		} drr_free;
308 		struct drr_write_byref {
309 			/* where to put the data */
310 			uint64_t drr_object;
311 			uint64_t drr_offset;
312 			uint64_t drr_length;
313 			uint64_t drr_toguid;
314 			/* where to find the prior copy of the data */
315 			uint64_t drr_refguid;
316 			uint64_t drr_refobject;
317 			uint64_t drr_refoffset;
318 			/* properties of the data */
319 			uint8_t drr_checksumtype;
320 			uint8_t drr_flags;
321 			uint8_t drr_pad2[6];
322 			ddt_key_t drr_key; /* deduplication key */
323 		} drr_write_byref;
324 		struct drr_spill {
325 			uint64_t drr_object;
326 			uint64_t drr_length;
327 			uint64_t drr_toguid;
328 			uint8_t drr_flags;
329 			uint8_t drr_compressiontype;
330 			uint8_t drr_pad[6];
331 			/* only nonzero for raw streams */
332 			uint64_t drr_compressed_size;
333 			uint8_t drr_salt[ZIO_DATA_SALT_LEN];
334 			uint8_t drr_iv[ZIO_DATA_IV_LEN];
335 			uint8_t drr_mac[ZIO_DATA_MAC_LEN];
336 			dmu_object_type_t drr_type;
337 			/* spill data follows */
338 		} drr_spill;
339 		struct drr_write_embedded {
340 			uint64_t drr_object;
341 			uint64_t drr_offset;
342 			/* logical length, should equal blocksize */
343 			uint64_t drr_length;
344 			uint64_t drr_toguid;
345 			uint8_t drr_compression;
346 			uint8_t drr_etype;
347 			uint8_t drr_pad[6];
348 			uint32_t drr_lsize; /* uncompressed size of payload */
349 			uint32_t drr_psize; /* compr. (real) size of payload */
350 			/* (possibly compressed) content follows */
351 		} drr_write_embedded;
352 		struct drr_object_range {
353 			uint64_t drr_firstobj;
354 			uint64_t drr_numslots;
355 			uint64_t drr_toguid;
356 			uint8_t drr_salt[ZIO_DATA_SALT_LEN];
357 			uint8_t drr_iv[ZIO_DATA_IV_LEN];
358 			uint8_t drr_mac[ZIO_DATA_MAC_LEN];
359 			uint8_t drr_flags;
360 			uint8_t drr_pad[3];
361 		} drr_object_range;
362 		struct drr_redact {
363 			uint64_t drr_object;
364 			uint64_t drr_offset;
365 			uint64_t drr_length;
366 			uint64_t drr_toguid;
367 		} drr_redact;
368 
369 		/*
370 		 * Note: drr_checksum is overlaid with all record types
371 		 * except DRR_BEGIN.  Therefore its (non-pad) members
372 		 * must not overlap with members from the other structs.
373 		 * We accomplish this by putting its members at the very
374 		 * end of the struct.
375 		 */
376 		struct drr_checksum {
377 			uint64_t drr_pad[34];
378 			/*
379 			 * fletcher-4 checksum of everything preceding the
380 			 * checksum.
381 			 */
382 			zio_cksum_t drr_checksum;
383 		} drr_checksum;
384 	} drr_u;
385 } dmu_replay_record_t;
386 
387 /* diff record range types */
388 typedef enum diff_type {
389 	DDR_NONE = 0x1,
390 	DDR_INUSE = 0x2,
391 	DDR_FREE = 0x4
392 } diff_type_t;
393 
394 /*
395  * The diff reports back ranges of free or in-use objects.
396  */
397 typedef struct dmu_diff_record {
398 	uint64_t ddr_type;
399 	uint64_t ddr_first;
400 	uint64_t ddr_last;
401 } dmu_diff_record_t;
402 
403 typedef struct zinject_record {
404 	uint64_t	zi_objset;
405 	uint64_t	zi_object;
406 	uint64_t	zi_start;
407 	uint64_t	zi_end;
408 	uint64_t	zi_guid;
409 	uint32_t	zi_level;
410 	uint32_t	zi_error;
411 	uint64_t	zi_type;
412 	uint32_t	zi_freq;
413 	uint32_t	zi_failfast;
414 	char		zi_func[MAXNAMELEN];
415 	uint32_t	zi_iotype;
416 	int32_t		zi_duration;
417 	uint64_t	zi_timer;
418 	uint64_t	zi_nlanes;
419 	uint32_t	zi_cmd;
420 	uint32_t	zi_dvas;
421 } zinject_record_t;
422 
423 #define	ZINJECT_NULL		0x1
424 #define	ZINJECT_FLUSH_ARC	0x2
425 #define	ZINJECT_UNLOAD_SPA	0x4
426 #define	ZINJECT_CALC_RANGE	0x8
427 
428 #define	ZEVENT_NONE		0x0
429 #define	ZEVENT_NONBLOCK		0x1
430 #define	ZEVENT_SIZE		1024
431 
432 #define	ZEVENT_SEEK_START	0
433 #define	ZEVENT_SEEK_END		UINT64_MAX
434 
435 /* scaled frequency ranges */
436 #define	ZI_PERCENTAGE_MIN	4294UL
437 #define	ZI_PERCENTAGE_MAX	UINT32_MAX
438 
439 #define	ZI_NO_DVA		(-1)
440 
441 typedef enum zinject_type {
442 	ZINJECT_UNINITIALIZED,
443 	ZINJECT_DATA_FAULT,
444 	ZINJECT_DEVICE_FAULT,
445 	ZINJECT_LABEL_FAULT,
446 	ZINJECT_IGNORED_WRITES,
447 	ZINJECT_PANIC,
448 	ZINJECT_DELAY_IO,
449 	ZINJECT_DECRYPT_FAULT,
450 } zinject_type_t;
451 
452 typedef struct zfs_share {
453 	uint64_t	z_exportdata;
454 	uint64_t	z_sharedata;
455 	uint64_t	z_sharetype;	/* 0 = share, 1 = unshare */
456 	uint64_t	z_sharemax;  /* max length of share string */
457 } zfs_share_t;
458 
459 /*
460  * ZFS file systems may behave the usual, POSIX-compliant way, where
461  * name lookups are case-sensitive.  They may also be set up so that
462  * all the name lookups are case-insensitive, or so that only some
463  * lookups, the ones that set an FIGNORECASE flag, are case-insensitive.
464  */
465 typedef enum zfs_case {
466 	ZFS_CASE_SENSITIVE,
467 	ZFS_CASE_INSENSITIVE,
468 	ZFS_CASE_MIXED
469 } zfs_case_t;
470 
471 /*
472  * Note: this struct must have the same layout in 32-bit and 64-bit, so
473  * that 32-bit processes (like /sbin/zfs) can pass it to the 64-bit
474  * kernel.  Therefore, we add padding to it so that no "hidden" padding
475  * is automatically added on 64-bit (but not on 32-bit).
476  */
477 typedef struct zfs_cmd {
478 	char		zc_name[MAXPATHLEN];	/* name of pool or dataset */
479 	uint64_t	zc_nvlist_src;		/* really (char *) */
480 	uint64_t	zc_nvlist_src_size;
481 	uint64_t	zc_nvlist_dst;		/* really (char *) */
482 	uint64_t	zc_nvlist_dst_size;
483 	boolean_t	zc_nvlist_dst_filled;	/* put an nvlist in dst? */
484 	int		zc_pad2;
485 
486 	/*
487 	 * The following members are for legacy ioctls which haven't been
488 	 * converted to the new method.
489 	 */
490 	uint64_t	zc_history;		/* really (char *) */
491 	char		zc_value[MAXPATHLEN * 2];
492 	char		zc_string[MAXNAMELEN];
493 	uint64_t	zc_guid;
494 	uint64_t	zc_nvlist_conf;		/* really (char *) */
495 	uint64_t	zc_nvlist_conf_size;
496 	uint64_t	zc_cookie;
497 	uint64_t	zc_objset_type;
498 	uint64_t	zc_perm_action;
499 	uint64_t	zc_history_len;
500 	uint64_t	zc_history_offset;
501 	uint64_t	zc_obj;
502 	uint64_t	zc_iflags;		/* internal to zfs(7fs) */
503 	zfs_share_t	zc_share;
504 	dmu_objset_stats_t zc_objset_stats;
505 	struct drr_begin zc_begin_record;
506 	zinject_record_t zc_inject_record;
507 	uint32_t	zc_defer_destroy;
508 	uint32_t	zc_flags;
509 	uint64_t	zc_action_handle;
510 	int		zc_cleanup_fd;
511 	uint8_t		zc_simple;
512 	uint8_t		zc_pad[3];		/* alignment */
513 	uint64_t	zc_sendobj;
514 	uint64_t	zc_fromobj;
515 	uint64_t	zc_createtxg;
516 	zfs_stat_t	zc_stat;
517 	uint64_t	zc_zoneid;
518 } zfs_cmd_t;
519 
520 typedef struct zfs_useracct {
521 	char zu_domain[256];
522 	uid_t zu_rid;
523 	uint32_t zu_pad;
524 	uint64_t zu_space;
525 } zfs_useracct_t;
526 
527 #define	ZFSDEV_MAX_MINOR	(1 << 16)
528 
529 #define	ZPOOL_EXPORT_AFTER_SPLIT 0x1
530 
531 #ifdef _KERNEL
532 struct objset;
533 struct zfsvfs;
534 
535 typedef struct zfs_creat {
536 	nvlist_t	*zct_zplprops;
537 	nvlist_t	*zct_props;
538 } zfs_creat_t;
539 
540 extern int zfs_secpolicy_snapshot_perms(const char *, cred_t *);
541 extern int zfs_secpolicy_rename_perms(const char *, const char *, cred_t *);
542 extern int zfs_secpolicy_destroy_perms(const char *, cred_t *);
543 extern void zfs_unmount_snap(const char *);
544 extern void zfs_destroy_unmount_origin(const char *);
545 extern int getzfsvfs_impl(struct objset *, struct zfsvfs **);
546 extern int getzfsvfs(const char *, struct zfsvfs **);
547 
548 enum zfsdev_state_type {
549 	ZST_ONEXIT,
550 	ZST_ZEVENT,
551 	ZST_ALL,
552 };
553 
554 /*
555  * The zfsdev_state_t structure is managed as a singly-linked list
556  * from which items are never deleted.  This allows for lock-free
557  * reading of the list so long as assignments to the zs_next and
558  * reads from zs_minor are performed atomically.  Empty items are
559  * indicated by storing -1 into zs_minor.
560  */
561 typedef struct zfsdev_state {
562 	struct zfsdev_state	*zs_next;	/* next zfsdev_state_t link */
563 	minor_t			zs_minor;	/* made up minor number */
564 	void			*zs_onexit;	/* onexit data */
565 	void			*zs_zevent;	/* zevent data */
566 } zfsdev_state_t;
567 
568 extern void *zfsdev_get_state(minor_t minor, enum zfsdev_state_type which);
569 extern int zfsdev_getminor(int fd, minor_t *minorp);
570 
571 extern uint_t zfs_fsyncer_key;
572 extern uint_t zfs_allow_log_key;
573 
574 #endif	/* _KERNEL */
575 
576 #ifdef	__cplusplus
577 }
578 #endif
579 
580 #endif	/* _SYS_ZFS_IOCTL_H */
581