xref: /titanic_50/usr/src/uts/common/fs/zfs/sys/dmu.h (revision ed22c7109fc5dd9e1b7a5d0333bdc7ad2718e2ab)
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  */
24 /*
25  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
26  */
27 
28 /* Portions Copyright 2010 Robert Milkowski */
29 
30 #ifndef	_SYS_DMU_H
31 #define	_SYS_DMU_H
32 
33 /*
34  * This file describes the interface that the DMU provides for its
35  * consumers.
36  *
37  * The DMU also interacts with the SPA.  That interface is described in
38  * dmu_spa.h.
39  */
40 
41 #include <sys/inttypes.h>
42 #include <sys/types.h>
43 #include <sys/param.h>
44 #include <sys/cred.h>
45 #include <sys/time.h>
46 
47 #ifdef	__cplusplus
48 extern "C" {
49 #endif
50 
51 struct uio;
52 struct xuio;
53 struct page;
54 struct vnode;
55 struct spa;
56 struct zilog;
57 struct zio;
58 struct blkptr;
59 struct zap_cursor;
60 struct dsl_dataset;
61 struct dsl_pool;
62 struct dnode;
63 struct drr_begin;
64 struct drr_end;
65 struct zbookmark;
66 struct spa;
67 struct nvlist;
68 struct arc_buf;
69 struct zio_prop;
70 struct sa_handle;
71 
72 typedef struct objset objset_t;
73 typedef struct dmu_tx dmu_tx_t;
74 typedef struct dsl_dir dsl_dir_t;
75 
76 typedef enum dmu_object_type {
77 	DMU_OT_NONE,
78 	/* general: */
79 	DMU_OT_OBJECT_DIRECTORY,	/* ZAP */
80 	DMU_OT_OBJECT_ARRAY,		/* UINT64 */
81 	DMU_OT_PACKED_NVLIST,		/* UINT8 (XDR by nvlist_pack/unpack) */
82 	DMU_OT_PACKED_NVLIST_SIZE,	/* UINT64 */
83 	DMU_OT_BPOBJ,			/* UINT64 */
84 	DMU_OT_BPOBJ_HDR,		/* UINT64 */
85 	/* spa: */
86 	DMU_OT_SPACE_MAP_HEADER,	/* UINT64 */
87 	DMU_OT_SPACE_MAP,		/* UINT64 */
88 	/* zil: */
89 	DMU_OT_INTENT_LOG,		/* UINT64 */
90 	/* dmu: */
91 	DMU_OT_DNODE,			/* DNODE */
92 	DMU_OT_OBJSET,			/* OBJSET */
93 	/* dsl: */
94 	DMU_OT_DSL_DIR,			/* UINT64 */
95 	DMU_OT_DSL_DIR_CHILD_MAP,	/* ZAP */
96 	DMU_OT_DSL_DS_SNAP_MAP,		/* ZAP */
97 	DMU_OT_DSL_PROPS,		/* ZAP */
98 	DMU_OT_DSL_DATASET,		/* UINT64 */
99 	/* zpl: */
100 	DMU_OT_ZNODE,			/* ZNODE */
101 	DMU_OT_OLDACL,			/* Old ACL */
102 	DMU_OT_PLAIN_FILE_CONTENTS,	/* UINT8 */
103 	DMU_OT_DIRECTORY_CONTENTS,	/* ZAP */
104 	DMU_OT_MASTER_NODE,		/* ZAP */
105 	DMU_OT_UNLINKED_SET,		/* ZAP */
106 	/* zvol: */
107 	DMU_OT_ZVOL,			/* UINT8 */
108 	DMU_OT_ZVOL_PROP,		/* ZAP */
109 	/* other; for testing only! */
110 	DMU_OT_PLAIN_OTHER,		/* UINT8 */
111 	DMU_OT_UINT64_OTHER,		/* UINT64 */
112 	DMU_OT_ZAP_OTHER,		/* ZAP */
113 	/* new object types: */
114 	DMU_OT_ERROR_LOG,		/* ZAP */
115 	DMU_OT_SPA_HISTORY,		/* UINT8 */
116 	DMU_OT_SPA_HISTORY_OFFSETS,	/* spa_his_phys_t */
117 	DMU_OT_POOL_PROPS,		/* ZAP */
118 	DMU_OT_DSL_PERMS,		/* ZAP */
119 	DMU_OT_ACL,			/* ACL */
120 	DMU_OT_SYSACL,			/* SYSACL */
121 	DMU_OT_FUID,			/* FUID table (Packed NVLIST UINT8) */
122 	DMU_OT_FUID_SIZE,		/* FUID table size UINT64 */
123 	DMU_OT_NEXT_CLONES,		/* ZAP */
124 	DMU_OT_SCAN_QUEUE,		/* ZAP */
125 	DMU_OT_USERGROUP_USED,		/* ZAP */
126 	DMU_OT_USERGROUP_QUOTA,		/* ZAP */
127 	DMU_OT_USERREFS,		/* ZAP */
128 	DMU_OT_DDT_ZAP,			/* ZAP */
129 	DMU_OT_DDT_STATS,		/* ZAP */
130 	DMU_OT_SA,			/* System attr */
131 	DMU_OT_SA_MASTER_NODE,		/* ZAP */
132 	DMU_OT_SA_ATTR_REGISTRATION,	/* ZAP */
133 	DMU_OT_SA_ATTR_LAYOUTS,		/* ZAP */
134 	DMU_OT_SCAN_XLATE,		/* ZAP */
135 	DMU_OT_DEDUP,			/* fake dedup BP from ddt_bp_create() */
136 	DMU_OT_DEADLIST,		/* ZAP */
137 	DMU_OT_DEADLIST_HDR,		/* UINT64 */
138 	DMU_OT_DSL_CLONES,		/* ZAP */
139 	DMU_OT_BPOBJ_SUBOBJ,		/* UINT64 */
140 	DMU_OT_NUMTYPES
141 } dmu_object_type_t;
142 
143 typedef enum dmu_objset_type {
144 	DMU_OST_NONE,
145 	DMU_OST_META,
146 	DMU_OST_ZFS,
147 	DMU_OST_ZVOL,
148 	DMU_OST_OTHER,			/* For testing only! */
149 	DMU_OST_ANY,			/* Be careful! */
150 	DMU_OST_NUMTYPES
151 } dmu_objset_type_t;
152 
153 void byteswap_uint64_array(void *buf, size_t size);
154 void byteswap_uint32_array(void *buf, size_t size);
155 void byteswap_uint16_array(void *buf, size_t size);
156 void byteswap_uint8_array(void *buf, size_t size);
157 void zap_byteswap(void *buf, size_t size);
158 void zfs_oldacl_byteswap(void *buf, size_t size);
159 void zfs_acl_byteswap(void *buf, size_t size);
160 void zfs_znode_byteswap(void *buf, size_t size);
161 
162 #define	DS_FIND_SNAPSHOTS	(1<<0)
163 #define	DS_FIND_CHILDREN	(1<<1)
164 
165 /*
166  * The maximum number of bytes that can be accessed as part of one
167  * operation, including metadata.
168  */
169 #define	DMU_MAX_ACCESS (10<<20) /* 10MB */
170 #define	DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */
171 
172 #define	DMU_USERUSED_OBJECT	(-1ULL)
173 #define	DMU_GROUPUSED_OBJECT	(-2ULL)
174 #define	DMU_DEADLIST_OBJECT	(-3ULL)
175 
176 /*
177  * artificial blkids for bonus buffer and spill blocks
178  */
179 #define	DMU_BONUS_BLKID		(-1ULL)
180 #define	DMU_SPILL_BLKID		(-2ULL)
181 /*
182  * Public routines to create, destroy, open, and close objsets.
183  */
184 int dmu_objset_hold(const char *name, void *tag, objset_t **osp);
185 int dmu_objset_own(const char *name, dmu_objset_type_t type,
186     boolean_t readonly, void *tag, objset_t **osp);
187 void dmu_objset_rele(objset_t *os, void *tag);
188 void dmu_objset_disown(objset_t *os, void *tag);
189 int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp);
190 
191 int dmu_objset_evict_dbufs(objset_t *os);
192 int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags,
193     void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg);
194 int dmu_objset_clone(const char *name, struct dsl_dataset *clone_origin,
195     uint64_t flags);
196 int dmu_objset_destroy(const char *name, boolean_t defer);
197 int dmu_snapshots_destroy(char *fsname, char *snapname, boolean_t defer);
198 int dmu_objset_snapshot(char *fsname, char *snapname, char *tag,
199     struct nvlist *props, boolean_t recursive, boolean_t temporary, int fd);
200 int dmu_objset_rename(const char *name, const char *newname,
201     boolean_t recursive);
202 int dmu_objset_find(char *name, int func(const char *, void *), void *arg,
203     int flags);
204 void dmu_objset_byteswap(void *buf, size_t size);
205 
206 typedef struct dmu_buf {
207 	uint64_t db_object;		/* object that this buffer is part of */
208 	uint64_t db_offset;		/* byte offset in this object */
209 	uint64_t db_size;		/* size of buffer in bytes */
210 	void *db_data;			/* data in buffer */
211 } dmu_buf_t;
212 
213 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr);
214 
215 /*
216  * The names of zap entries in the DIRECTORY_OBJECT of the MOS.
217  */
218 #define	DMU_POOL_DIRECTORY_OBJECT	1
219 #define	DMU_POOL_CONFIG			"config"
220 #define	DMU_POOL_ROOT_DATASET		"root_dataset"
221 #define	DMU_POOL_SYNC_BPOBJ		"sync_bplist"
222 #define	DMU_POOL_ERRLOG_SCRUB		"errlog_scrub"
223 #define	DMU_POOL_ERRLOG_LAST		"errlog_last"
224 #define	DMU_POOL_SPARES			"spares"
225 #define	DMU_POOL_DEFLATE		"deflate"
226 #define	DMU_POOL_HISTORY		"history"
227 #define	DMU_POOL_PROPS			"pool_props"
228 #define	DMU_POOL_L2CACHE		"l2cache"
229 #define	DMU_POOL_TMP_USERREFS		"tmp_userrefs"
230 #define	DMU_POOL_DDT			"DDT-%s-%s-%s"
231 #define	DMU_POOL_DDT_STATS		"DDT-statistics"
232 #define	DMU_POOL_CREATION_VERSION	"creation_version"
233 #define	DMU_POOL_SCAN			"scan"
234 #define	DMU_POOL_FREE_BPOBJ		"free_bpobj"
235 
236 /*
237  * Allocate an object from this objset.  The range of object numbers
238  * available is (0, DN_MAX_OBJECT).  Object 0 is the meta-dnode.
239  *
240  * The transaction must be assigned to a txg.  The newly allocated
241  * object will be "held" in the transaction (ie. you can modify the
242  * newly allocated object in this transaction).
243  *
244  * dmu_object_alloc() chooses an object and returns it in *objectp.
245  *
246  * dmu_object_claim() allocates a specific object number.  If that
247  * number is already allocated, it fails and returns EEXIST.
248  *
249  * Return 0 on success, or ENOSPC or EEXIST as specified above.
250  */
251 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot,
252     int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
253 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot,
254     int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
255 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot,
256     int blocksize, dmu_object_type_t bonustype, int bonuslen);
257 
258 /*
259  * Free an object from this objset.
260  *
261  * The object's data will be freed as well (ie. you don't need to call
262  * dmu_free(object, 0, -1, tx)).
263  *
264  * The object need not be held in the transaction.
265  *
266  * If there are any holds on this object's buffers (via dmu_buf_hold()),
267  * or tx holds on the object (via dmu_tx_hold_object()), you can not
268  * free it; it fails and returns EBUSY.
269  *
270  * If the object is not allocated, it fails and returns ENOENT.
271  *
272  * Return 0 on success, or EBUSY or ENOENT as specified above.
273  */
274 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx);
275 
276 /*
277  * Find the next allocated or free object.
278  *
279  * The objectp parameter is in-out.  It will be updated to be the next
280  * object which is allocated.  Ignore objects which have not been
281  * modified since txg.
282  *
283  * XXX Can only be called on a objset with no dirty data.
284  *
285  * Returns 0 on success, or ENOENT if there are no more objects.
286  */
287 int dmu_object_next(objset_t *os, uint64_t *objectp,
288     boolean_t hole, uint64_t txg);
289 
290 /*
291  * Set the data blocksize for an object.
292  *
293  * The object cannot have any blocks allcated beyond the first.  If
294  * the first block is allocated already, the new size must be greater
295  * than the current block size.  If these conditions are not met,
296  * ENOTSUP will be returned.
297  *
298  * Returns 0 on success, or EBUSY if there are any holds on the object
299  * contents, or ENOTSUP as described above.
300  */
301 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size,
302     int ibs, dmu_tx_t *tx);
303 
304 /*
305  * Set the checksum property on a dnode.  The new checksum algorithm will
306  * apply to all newly written blocks; existing blocks will not be affected.
307  */
308 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
309     dmu_tx_t *tx);
310 
311 /*
312  * Set the compress property on a dnode.  The new compression algorithm will
313  * apply to all newly written blocks; existing blocks will not be affected.
314  */
315 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
316     dmu_tx_t *tx);
317 
318 /*
319  * Decide how to write a block: checksum, compression, number of copies, etc.
320  */
321 #define	WP_NOFILL	0x1
322 #define	WP_DMU_SYNC	0x2
323 #define	WP_SPILL	0x4
324 
325 void dmu_write_policy(objset_t *os, struct dnode *dn, int level, int wp,
326     struct zio_prop *zp);
327 /*
328  * The bonus data is accessed more or less like a regular buffer.
329  * You must dmu_bonus_hold() to get the buffer, which will give you a
330  * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus
331  * data.  As with any normal buffer, you must call dmu_buf_read() to
332  * read db_data, dmu_buf_will_dirty() before modifying it, and the
333  * object must be held in an assigned transaction before calling
334  * dmu_buf_will_dirty.  You may use dmu_buf_set_user() on the bonus
335  * buffer as well.  You must release your hold with dmu_buf_rele().
336  */
337 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **);
338 int dmu_bonus_max(void);
339 int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *);
340 int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *);
341 dmu_object_type_t dmu_get_bonustype(dmu_buf_t *);
342 int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *);
343 
344 /*
345  * Special spill buffer support used by "SA" framework
346  */
347 
348 int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp);
349 int dmu_spill_hold_by_dnode(struct dnode *dn, uint32_t flags,
350     void *tag, dmu_buf_t **dbp);
351 int dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp);
352 
353 /*
354  * Obtain the DMU buffer from the specified object which contains the
355  * specified offset.  dmu_buf_hold() puts a "hold" on the buffer, so
356  * that it will remain in memory.  You must release the hold with
357  * dmu_buf_rele().  You musn't access the dmu_buf_t after releasing your
358  * hold.  You must have a hold on any dmu_buf_t* you pass to the DMU.
359  *
360  * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill
361  * on the returned buffer before reading or writing the buffer's
362  * db_data.  The comments for those routines describe what particular
363  * operations are valid after calling them.
364  *
365  * The object number must be a valid, allocated object number.
366  */
367 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
368     void *tag, dmu_buf_t **, int flags);
369 void dmu_buf_add_ref(dmu_buf_t *db, void* tag);
370 void dmu_buf_rele(dmu_buf_t *db, void *tag);
371 uint64_t dmu_buf_refcount(dmu_buf_t *db);
372 
373 /*
374  * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a
375  * range of an object.  A pointer to an array of dmu_buf_t*'s is
376  * returned (in *dbpp).
377  *
378  * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and
379  * frees the array.  The hold on the array of buffers MUST be released
380  * with dmu_buf_rele_array.  You can NOT release the hold on each buffer
381  * individually with dmu_buf_rele.
382  */
383 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
384     uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp);
385 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag);
386 
387 /*
388  * Returns NULL on success, or the existing user ptr if it's already
389  * been set.
390  *
391  * user_ptr is for use by the user and can be obtained via dmu_buf_get_user().
392  *
393  * user_data_ptr_ptr should be NULL, or a pointer to a pointer which
394  * will be set to db->db_data when you are allowed to access it.  Note
395  * that db->db_data (the pointer) can change when you do dmu_buf_read(),
396  * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill().
397  * *user_data_ptr_ptr will be set to the new value when it changes.
398  *
399  * If non-NULL, pageout func will be called when this buffer is being
400  * excised from the cache, so that you can clean up the data structure
401  * pointed to by user_ptr.
402  *
403  * dmu_evict_user() will call the pageout func for all buffers in a
404  * objset with a given pageout func.
405  */
406 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr,
407     dmu_buf_evict_func_t *pageout_func);
408 /*
409  * set_user_ie is the same as set_user, but request immediate eviction
410  * when hold count goes to zero.
411  */
412 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr,
413     void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func);
414 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr,
415     void *user_ptr, void *user_data_ptr_ptr,
416     dmu_buf_evict_func_t *pageout_func);
417 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func);
418 
419 /*
420  * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set.
421  */
422 void *dmu_buf_get_user(dmu_buf_t *db);
423 
424 /*
425  * Indicate that you are going to modify the buffer's data (db_data).
426  *
427  * The transaction (tx) must be assigned to a txg (ie. you've called
428  * dmu_tx_assign()).  The buffer's object must be held in the tx
429  * (ie. you've called dmu_tx_hold_object(tx, db->db_object)).
430  */
431 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx);
432 
433 /*
434  * Tells if the given dbuf is freeable.
435  */
436 boolean_t dmu_buf_freeable(dmu_buf_t *);
437 
438 /*
439  * You must create a transaction, then hold the objects which you will
440  * (or might) modify as part of this transaction.  Then you must assign
441  * the transaction to a transaction group.  Once the transaction has
442  * been assigned, you can modify buffers which belong to held objects as
443  * part of this transaction.  You can't modify buffers before the
444  * transaction has been assigned; you can't modify buffers which don't
445  * belong to objects which this transaction holds; you can't hold
446  * objects once the transaction has been assigned.  You may hold an
447  * object which you are going to free (with dmu_object_free()), but you
448  * don't have to.
449  *
450  * You can abort the transaction before it has been assigned.
451  *
452  * Note that you may hold buffers (with dmu_buf_hold) at any time,
453  * regardless of transaction state.
454  */
455 
456 #define	DMU_NEW_OBJECT	(-1ULL)
457 #define	DMU_OBJECT_END	(-1ULL)
458 
459 dmu_tx_t *dmu_tx_create(objset_t *os);
460 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
461 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off,
462     uint64_t len);
463 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name);
464 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object);
465 void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object);
466 void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow);
467 void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size);
468 void dmu_tx_abort(dmu_tx_t *tx);
469 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how);
470 void dmu_tx_wait(dmu_tx_t *tx);
471 void dmu_tx_commit(dmu_tx_t *tx);
472 
473 /*
474  * To register a commit callback, dmu_tx_callback_register() must be called.
475  *
476  * dcb_data is a pointer to caller private data that is passed on as a
477  * callback parameter. The caller is responsible for properly allocating and
478  * freeing it.
479  *
480  * When registering a callback, the transaction must be already created, but
481  * it cannot be committed or aborted. It can be assigned to a txg or not.
482  *
483  * The callback will be called after the transaction has been safely written
484  * to stable storage and will also be called if the dmu_tx is aborted.
485  * If there is any error which prevents the transaction from being committed to
486  * disk, the callback will be called with a value of error != 0.
487  */
488 typedef void dmu_tx_callback_func_t(void *dcb_data, int error);
489 
490 void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func,
491     void *dcb_data);
492 
493 /*
494  * Free up the data blocks for a defined range of a file.  If size is
495  * zero, the range from offset to end-of-file is freed.
496  */
497 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
498 	uint64_t size, dmu_tx_t *tx);
499 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset,
500 	uint64_t size);
501 int dmu_free_object(objset_t *os, uint64_t object);
502 
503 /*
504  * Convenience functions.
505  *
506  * Canfail routines will return 0 on success, or an errno if there is a
507  * nonrecoverable I/O error.
508  */
509 #define	DMU_READ_PREFETCH	0 /* prefetch */
510 #define	DMU_READ_NO_PREFETCH	1 /* don't prefetch */
511 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
512 	void *buf, uint32_t flags);
513 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
514 	const void *buf, dmu_tx_t *tx);
515 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
516 	dmu_tx_t *tx);
517 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size);
518 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size,
519     dmu_tx_t *tx);
520 int dmu_write_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size,
521     dmu_tx_t *tx);
522 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset,
523     uint64_t size, struct page *pp, dmu_tx_t *tx);
524 struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size);
525 void dmu_return_arcbuf(struct arc_buf *buf);
526 void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf,
527     dmu_tx_t *tx);
528 int dmu_xuio_init(struct xuio *uio, int niov);
529 void dmu_xuio_fini(struct xuio *uio);
530 int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off,
531     size_t n);
532 int dmu_xuio_cnt(struct xuio *uio);
533 struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i);
534 void dmu_xuio_clear(struct xuio *uio, int i);
535 void xuio_stat_wbuf_copied();
536 void xuio_stat_wbuf_nocopy();
537 
538 extern int zfs_prefetch_disable;
539 
540 /*
541  * Asynchronously try to read in the data.
542  */
543 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset,
544     uint64_t len);
545 
546 typedef struct dmu_object_info {
547 	/* All sizes are in bytes unless otherwise indicated. */
548 	uint32_t doi_data_block_size;
549 	uint32_t doi_metadata_block_size;
550 	dmu_object_type_t doi_type;
551 	dmu_object_type_t doi_bonus_type;
552 	uint64_t doi_bonus_size;
553 	uint8_t doi_indirection;		/* 2 = dnode->indirect->data */
554 	uint8_t doi_checksum;
555 	uint8_t doi_compress;
556 	uint8_t doi_pad[5];
557 	uint64_t doi_physical_blocks_512;	/* data + metadata, 512b blks */
558 	uint64_t doi_max_offset;
559 	uint64_t doi_fill_count;		/* number of non-empty blocks */
560 } dmu_object_info_t;
561 
562 typedef void arc_byteswap_func_t(void *buf, size_t size);
563 
564 typedef struct dmu_object_type_info {
565 	arc_byteswap_func_t	*ot_byteswap;
566 	boolean_t		ot_metadata;
567 	char			*ot_name;
568 } dmu_object_type_info_t;
569 
570 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES];
571 
572 /*
573  * Get information on a DMU object.
574  *
575  * Return 0 on success or ENOENT if object is not allocated.
576  *
577  * If doi is NULL, just indicates whether the object exists.
578  */
579 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi);
580 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi);
581 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi);
582 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize,
583     u_longlong_t *nblk512);
584 
585 typedef struct dmu_objset_stats {
586 	uint64_t dds_num_clones; /* number of clones of this */
587 	uint64_t dds_creation_txg;
588 	uint64_t dds_guid;
589 	dmu_objset_type_t dds_type;
590 	uint8_t dds_is_snapshot;
591 	uint8_t dds_inconsistent;
592 	char dds_origin[MAXNAMELEN];
593 } dmu_objset_stats_t;
594 
595 /*
596  * Get stats on a dataset.
597  */
598 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat);
599 
600 /*
601  * Add entries to the nvlist for all the objset's properties.  See
602  * zfs_prop_table[] and zfs(1m) for details on the properties.
603  */
604 void dmu_objset_stats(objset_t *os, struct nvlist *nv);
605 
606 /*
607  * Get the space usage statistics for statvfs().
608  *
609  * refdbytes is the amount of space "referenced" by this objset.
610  * availbytes is the amount of space available to this objset, taking
611  * into account quotas & reservations, assuming that no other objsets
612  * use the space first.  These values correspond to the 'referenced' and
613  * 'available' properties, described in the zfs(1m) manpage.
614  *
615  * usedobjs and availobjs are the number of objects currently allocated,
616  * and available.
617  */
618 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
619     uint64_t *usedobjsp, uint64_t *availobjsp);
620 
621 /*
622  * The fsid_guid is a 56-bit ID that can change to avoid collisions.
623  * (Contrast with the ds_guid which is a 64-bit ID that will never
624  * change, so there is a small probability that it will collide.)
625  */
626 uint64_t dmu_objset_fsid_guid(objset_t *os);
627 
628 /*
629  * Get the [cm]time for an objset's snapshot dir
630  */
631 timestruc_t dmu_objset_snap_cmtime(objset_t *os);
632 
633 int dmu_objset_is_snapshot(objset_t *os);
634 
635 extern struct spa *dmu_objset_spa(objset_t *os);
636 extern struct zilog *dmu_objset_zil(objset_t *os);
637 extern struct dsl_pool *dmu_objset_pool(objset_t *os);
638 extern struct dsl_dataset *dmu_objset_ds(objset_t *os);
639 extern void dmu_objset_name(objset_t *os, char *buf);
640 extern dmu_objset_type_t dmu_objset_type(objset_t *os);
641 extern uint64_t dmu_objset_id(objset_t *os);
642 extern uint64_t dmu_objset_syncprop(objset_t *os);
643 extern uint64_t dmu_objset_logbias(objset_t *os);
644 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
645     uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
646 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
647     int maxlen, boolean_t *conflict);
648 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,
649     uint64_t *idp, uint64_t *offp);
650 
651 typedef int objset_used_cb_t(dmu_object_type_t bonustype,
652     void *bonus, uint64_t *userp, uint64_t *groupp);
653 extern void dmu_objset_register_type(dmu_objset_type_t ost,
654     objset_used_cb_t *cb);
655 extern void dmu_objset_set_user(objset_t *os, void *user_ptr);
656 extern void *dmu_objset_get_user(objset_t *os);
657 
658 /*
659  * Return the txg number for the given assigned transaction.
660  */
661 uint64_t dmu_tx_get_txg(dmu_tx_t *tx);
662 
663 /*
664  * Synchronous write.
665  * If a parent zio is provided this function initiates a write on the
666  * provided buffer as a child of the parent zio.
667  * In the absence of a parent zio, the write is completed synchronously.
668  * At write completion, blk is filled with the bp of the written block.
669  * Note that while the data covered by this function will be on stable
670  * storage when the write completes this new data does not become a
671  * permanent part of the file until the associated transaction commits.
672  */
673 
674 /*
675  * {zfs,zvol,ztest}_get_done() args
676  */
677 typedef struct zgd {
678 	struct zilog	*zgd_zilog;
679 	struct blkptr	*zgd_bp;
680 	dmu_buf_t	*zgd_db;
681 	struct rl	*zgd_rl;
682 	void		*zgd_private;
683 } zgd_t;
684 
685 typedef void dmu_sync_cb_t(zgd_t *arg, int error);
686 int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd);
687 
688 /*
689  * Find the next hole or data block in file starting at *off
690  * Return found offset in *off. Return ESRCH for end of file.
691  */
692 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole,
693     uint64_t *off);
694 
695 /*
696  * Initial setup and final teardown.
697  */
698 extern void dmu_init(void);
699 extern void dmu_fini(void);
700 
701 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
702     uint64_t object, uint64_t offset, int len);
703 void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
704     dmu_traverse_cb_t cb, void *arg);
705 
706 int dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
707     struct vnode *vp, offset_t *off);
708 
709 typedef struct dmu_recv_cookie {
710 	/*
711 	 * This structure is opaque!
712 	 *
713 	 * If logical and real are different, we are recving the stream
714 	 * into the "real" temporary clone, and then switching it with
715 	 * the "logical" target.
716 	 */
717 	struct dsl_dataset *drc_logical_ds;
718 	struct dsl_dataset *drc_real_ds;
719 	struct drr_begin *drc_drrb;
720 	char *drc_tosnap;
721 	char *drc_top_ds;
722 	boolean_t drc_newfs;
723 	boolean_t drc_force;
724 	struct avl_tree *drc_guid_to_ds_map;
725 } dmu_recv_cookie_t;
726 
727 int dmu_recv_begin(char *tofs, char *tosnap, char *topds, struct drr_begin *,
728     boolean_t force, objset_t *origin, dmu_recv_cookie_t *);
729 int dmu_recv_stream(dmu_recv_cookie_t *drc, struct vnode *vp, offset_t *voffp,
730     int cleanup_fd, uint64_t *action_handlep);
731 int dmu_recv_end(dmu_recv_cookie_t *drc);
732 
733 int dmu_diff(objset_t *tosnap, objset_t *fromsnap, struct vnode *vp,
734     offset_t *off);
735 
736 /* CRC64 table */
737 #define	ZFS_CRC64_POLY	0xC96C5795D7870F42ULL	/* ECMA-182, reflected form */
738 extern uint64_t zfs_crc64_table[256];
739 
740 #ifdef	__cplusplus
741 }
742 #endif
743 
744 #endif	/* _SYS_DMU_H */
745