xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/zil.h (revision b1e2e3fb17324e9ddf43db264a0c64da7756d9e6)
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, 2017 by Delphix. All rights reserved.
24  * Copyright (c) 2014 Integros [integros.com]
25  */
26 
27 /* Portions Copyright 2010 Robert Milkowski */
28 
29 #ifndef	_SYS_ZIL_H
30 #define	_SYS_ZIL_H
31 
32 #include <sys/types.h>
33 #include <sys/spa.h>
34 #include <sys/zio.h>
35 #include <sys/dmu.h>
36 
37 #ifdef	__cplusplus
38 extern "C" {
39 #endif
40 
41 struct dsl_pool;
42 struct dsl_dataset;
43 struct lwb;
44 
45 /*
46  * Intent log format:
47  *
48  * Each objset has its own intent log.  The log header (zil_header_t)
49  * for objset N's intent log is kept in the Nth object of the SPA's
50  * intent_log objset.  The log header points to a chain of log blocks,
51  * each of which contains log records (i.e., transactions) followed by
52  * a log block trailer (zil_trailer_t).  The format of a log record
53  * depends on the record (or transaction) type, but all records begin
54  * with a common structure that defines the type, length, and txg.
55  */
56 
57 /*
58  * Intent log header - this on disk structure holds fields to manage
59  * the log.  All fields are 64 bit to easily handle cross architectures.
60  */
61 typedef struct zil_header {
62 	uint64_t zh_claim_txg;	/* txg in which log blocks were claimed */
63 	uint64_t zh_replay_seq;	/* highest replayed sequence number */
64 	blkptr_t zh_log;	/* log chain */
65 	uint64_t zh_claim_blk_seq; /* highest claimed block sequence number */
66 	uint64_t zh_flags;	/* header flags */
67 	uint64_t zh_claim_lr_seq; /* highest claimed lr sequence number */
68 	uint64_t zh_pad[3];
69 } zil_header_t;
70 
71 /*
72  * zh_flags bit settings
73  */
74 #define	ZIL_REPLAY_NEEDED	0x1	/* replay needed - internal only */
75 #define	ZIL_CLAIM_LR_SEQ_VALID	0x2	/* zh_claim_lr_seq field is valid */
76 
77 /*
78  * Log block chaining.
79  *
80  * Log blocks are chained together. Originally they were chained at the
81  * end of the block. For performance reasons the chain was moved to the
82  * beginning of the block which allows writes for only the data being used.
83  * The older position is supported for backwards compatability.
84  *
85  * The zio_eck_t contains a zec_cksum which for the intent log is
86  * the sequence number of this log block. A seq of 0 is invalid.
87  * The zec_cksum is checked by the SPA against the sequence
88  * number passed in the blk_cksum field of the blkptr_t
89  */
90 typedef struct zil_chain {
91 	uint64_t zc_pad;
92 	blkptr_t zc_next_blk;	/* next block in chain */
93 	uint64_t zc_nused;	/* bytes in log block used */
94 	zio_eck_t zc_eck;	/* block trailer */
95 } zil_chain_t;
96 
97 #define	ZIL_MIN_BLKSZ	4096ULL
98 
99 /*
100  * ziltest is by and large an ugly hack, but very useful in
101  * checking replay without tedious work.
102  * When running ziltest we want to keep all itx's and so maintain
103  * a single list in the zl_itxg[] that uses a high txg: ZILTEST_TXG
104  * We subtract TXG_CONCURRENT_STATES to allow for common code.
105  */
106 #define	ZILTEST_TXG (UINT64_MAX - TXG_CONCURRENT_STATES)
107 
108 /*
109  * The words of a log block checksum.
110  */
111 #define	ZIL_ZC_GUID_0	0
112 #define	ZIL_ZC_GUID_1	1
113 #define	ZIL_ZC_OBJSET	2
114 #define	ZIL_ZC_SEQ	3
115 
116 typedef enum zil_create {
117 	Z_FILE,
118 	Z_DIR,
119 	Z_XATTRDIR,
120 } zil_create_t;
121 
122 /*
123  * size of xvattr log section.
124  * its composed of lr_attr_t + xvattr bitmap + 2 64 bit timestamps
125  * for create time and a single 64 bit integer for all of the attributes,
126  * and 4 64 bit integers (32 bytes) for the scanstamp.
127  *
128  */
129 
130 #define	ZIL_XVAT_SIZE(mapsize) \
131 	sizeof (lr_attr_t) + (sizeof (uint32_t) * (mapsize - 1)) + \
132 	(sizeof (uint64_t) * 7)
133 
134 /*
135  * Size of ACL in log.  The ACE data is padded out to properly align
136  * on 8 byte boundary.
137  */
138 
139 #define	ZIL_ACE_LENGTH(x)	(roundup(x, sizeof (uint64_t)))
140 
141 /*
142  * Intent log transaction types and record structures
143  */
144 #define	TX_COMMIT		0	/* Commit marker (no on-disk state) */
145 #define	TX_CREATE		1	/* Create file */
146 #define	TX_MKDIR		2	/* Make directory */
147 #define	TX_MKXATTR		3	/* Make XATTR directory */
148 #define	TX_SYMLINK		4	/* Create symbolic link to a file */
149 #define	TX_REMOVE		5	/* Remove file */
150 #define	TX_RMDIR		6	/* Remove directory */
151 #define	TX_LINK			7	/* Create hard link to a file */
152 #define	TX_RENAME		8	/* Rename a file */
153 #define	TX_WRITE		9	/* File write */
154 #define	TX_TRUNCATE		10	/* Truncate a file */
155 #define	TX_SETATTR		11	/* Set file attributes */
156 #define	TX_ACL_V0		12	/* Set old formatted ACL */
157 #define	TX_ACL			13	/* Set ACL */
158 #define	TX_CREATE_ACL		14	/* create with ACL */
159 #define	TX_CREATE_ATTR		15	/* create + attrs */
160 #define	TX_CREATE_ACL_ATTR	16	/* create with ACL + attrs */
161 #define	TX_MKDIR_ACL		17	/* mkdir with ACL */
162 #define	TX_MKDIR_ATTR		18	/* mkdir with attr */
163 #define	TX_MKDIR_ACL_ATTR	19	/* mkdir with ACL + attrs */
164 #define	TX_WRITE2		20	/* dmu_sync EALREADY write */
165 #define	TX_MAX_TYPE		21	/* Max transaction type */
166 
167 /*
168  * The transactions for mkdir, symlink, remove, rmdir, link, and rename
169  * may have the following bit set, indicating the original request
170  * specified case-insensitive handling of names.
171  */
172 #define	TX_CI	((uint64_t)0x1 << 63) /* case-insensitive behavior requested */
173 
174 /*
175  * Transactions for write, truncate, setattr, acl_v0, and acl can be logged
176  * out of order.  For convenience in the code, all such records must have
177  * lr_foid at the same offset.
178  */
179 #define	TX_OOO(txtype)			\
180 	((txtype) == TX_WRITE ||	\
181 	(txtype) == TX_TRUNCATE ||	\
182 	(txtype) == TX_SETATTR ||	\
183 	(txtype) == TX_ACL_V0 ||	\
184 	(txtype) == TX_ACL ||		\
185 	(txtype) == TX_WRITE2)
186 
187 /*
188  * The number of dnode slots consumed by the object is stored in the 8
189  * unused upper bits of the object ID. We subtract 1 from the value
190  * stored on disk for compatibility with implementations that don't
191  * support large dnodes. The slot count for a single-slot dnode will
192  * contain 0 for those bits to preserve the log record format for
193  * "small" dnodes.
194  */
195 #define	LR_FOID_GET_SLOTS(oid) (BF64_GET((oid), 56, 8) + 1)
196 #define	LR_FOID_SET_SLOTS(oid, x) BF64_SET((oid), 56, 8, (x) - 1)
197 #define	LR_FOID_GET_OBJ(oid) BF64_GET((oid), 0, DN_MAX_OBJECT_SHIFT)
198 #define	LR_FOID_SET_OBJ(oid, x) BF64_SET((oid), 0, DN_MAX_OBJECT_SHIFT, (x))
199 
200 /*
201  * Format of log records.
202  * The fields are carefully defined to allow them to be aligned
203  * and sized the same on sparc & intel architectures.
204  * Each log record has a common structure at the beginning.
205  *
206  * The log record on disk (lrc_seq) holds the sequence number of all log
207  * records which is used to ensure we don't replay the same record.
208  */
209 typedef struct {			/* common log record header */
210 	uint64_t	lrc_txtype;	/* intent log transaction type */
211 	uint64_t	lrc_reclen;	/* transaction record length */
212 	uint64_t	lrc_txg;	/* dmu transaction group number */
213 	uint64_t	lrc_seq;	/* see comment above */
214 } lr_t;
215 
216 /*
217  * Common start of all out-of-order record types (TX_OOO() above).
218  */
219 typedef struct {
220 	lr_t		lr_common;	/* common portion of log record */
221 	uint64_t	lr_foid;	/* object id */
222 } lr_ooo_t;
223 
224 /*
225  * Handle option extended vattr attributes.
226  *
227  * Whenever new attributes are added the version number
228  * will need to be updated as will code in
229  * zfs_log.c and zfs_replay.c
230  */
231 typedef struct {
232 	uint32_t	lr_attr_masksize; /* number of elements in array */
233 	uint32_t	lr_attr_bitmap; /* First entry of array */
234 	/* remainder of array and any additional fields */
235 } lr_attr_t;
236 
237 /*
238  * log record for creates without optional ACL.
239  * This log record does support optional xvattr_t attributes.
240  */
241 typedef struct {
242 	lr_t		lr_common;	/* common portion of log record */
243 	uint64_t	lr_doid;	/* object id of directory */
244 	uint64_t	lr_foid;	/* object id of created file object */
245 	uint64_t	lr_mode;	/* mode of object */
246 	uint64_t	lr_uid;		/* uid of object */
247 	uint64_t	lr_gid;		/* gid of object */
248 	uint64_t	lr_gen;		/* generation (txg of creation) */
249 	uint64_t	lr_crtime[2];	/* creation time */
250 	uint64_t	lr_rdev;	/* rdev of object to create */
251 	/* name of object to create follows this */
252 	/* for symlinks, link content follows name */
253 	/* for creates with xvattr data, the name follows the xvattr info */
254 } lr_create_t;
255 
256 /*
257  * FUID ACL record will be an array of ACEs from the original ACL.
258  * If this array includes ephemeral IDs, the record will also include
259  * an array of log-specific FUIDs to replace the ephemeral IDs.
260  * Only one copy of each unique domain will be present, so the log-specific
261  * FUIDs will use an index into a compressed domain table.  On replay this
262  * information will be used to construct real FUIDs (and bypass idmap,
263  * since it may not be available).
264  */
265 
266 /*
267  * Log record for creates with optional ACL
268  * This log record is also used for recording any FUID
269  * information needed for replaying the create.  If the
270  * file doesn't have any actual ACEs then the lr_aclcnt
271  * would be zero.
272  *
273  * After lr_acl_flags, there are a lr_acl_bytes number of variable sized ace's.
274  * If create is also setting xvattr's, then acl data follows xvattr.
275  * If ACE FUIDs are needed then they will follow the xvattr_t.  Following
276  * the FUIDs will be the domain table information.  The FUIDs for the owner
277  * and group will be in lr_create.  Name follows ACL data.
278  */
279 typedef struct {
280 	lr_create_t	lr_create;	/* common create portion */
281 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
282 	uint64_t	lr_domcnt;	/* number of unique domains */
283 	uint64_t	lr_fuidcnt;	/* number of real fuids */
284 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
285 	uint64_t	lr_acl_flags;	/* ACL flags */
286 } lr_acl_create_t;
287 
288 typedef struct {
289 	lr_t		lr_common;	/* common portion of log record */
290 	uint64_t	lr_doid;	/* obj id of directory */
291 	/* name of object to remove follows this */
292 } lr_remove_t;
293 
294 typedef struct {
295 	lr_t		lr_common;	/* common portion of log record */
296 	uint64_t	lr_doid;	/* obj id of directory */
297 	uint64_t	lr_link_obj;	/* obj id of link */
298 	/* name of object to link follows this */
299 } lr_link_t;
300 
301 typedef struct {
302 	lr_t		lr_common;	/* common portion of log record */
303 	uint64_t	lr_sdoid;	/* obj id of source directory */
304 	uint64_t	lr_tdoid;	/* obj id of target directory */
305 	/* 2 strings: names of source and destination follow this */
306 } lr_rename_t;
307 
308 typedef struct {
309 	lr_t		lr_common;	/* common portion of log record */
310 	uint64_t	lr_foid;	/* file object to write */
311 	uint64_t	lr_offset;	/* offset to write to */
312 	uint64_t	lr_length;	/* user data length to write */
313 	uint64_t	lr_blkoff;	/* no longer used */
314 	blkptr_t	lr_blkptr;	/* spa block pointer for replay */
315 	/* write data will follow for small writes */
316 } lr_write_t;
317 
318 typedef struct {
319 	lr_t		lr_common;	/* common portion of log record */
320 	uint64_t	lr_foid;	/* object id of file to truncate */
321 	uint64_t	lr_offset;	/* offset to truncate from */
322 	uint64_t	lr_length;	/* length to truncate */
323 } lr_truncate_t;
324 
325 typedef struct {
326 	lr_t		lr_common;	/* common portion of log record */
327 	uint64_t	lr_foid;	/* file object to change attributes */
328 	uint64_t	lr_mask;	/* mask of attributes to set */
329 	uint64_t	lr_mode;	/* mode to set */
330 	uint64_t	lr_uid;		/* uid to set */
331 	uint64_t	lr_gid;		/* gid to set */
332 	uint64_t	lr_size;	/* size to set */
333 	uint64_t	lr_atime[2];	/* access time */
334 	uint64_t	lr_mtime[2];	/* modification time */
335 	/* optional attribute lr_attr_t may be here */
336 } lr_setattr_t;
337 
338 typedef struct {
339 	lr_t		lr_common;	/* common portion of log record */
340 	uint64_t	lr_foid;	/* obj id of file */
341 	uint64_t	lr_aclcnt;	/* number of acl entries */
342 	/* lr_aclcnt number of ace_t entries follow this */
343 } lr_acl_v0_t;
344 
345 typedef struct {
346 	lr_t		lr_common;	/* common portion of log record */
347 	uint64_t	lr_foid;	/* obj id of file */
348 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
349 	uint64_t	lr_domcnt;	/* number of unique domains */
350 	uint64_t	lr_fuidcnt;	/* number of real fuids */
351 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
352 	uint64_t	lr_acl_flags;	/* ACL flags */
353 	/* lr_acl_bytes number of variable sized ace's follows */
354 } lr_acl_t;
355 
356 /*
357  * ZIL structure definitions, interface function prototype and globals.
358  */
359 
360 /*
361  * Writes are handled in three different ways:
362  *
363  * WR_INDIRECT:
364  *    In this mode, if we need to commit the write later, then the block
365  *    is immediately written into the file system (using dmu_sync),
366  *    and a pointer to the block is put into the log record.
367  *    When the txg commits the block is linked in.
368  *    This saves additionally writing the data into the log record.
369  *    There are a few requirements for this to occur:
370  *	- write is greater than zfs/zvol_immediate_write_sz
371  *	- not using slogs (as slogs are assumed to always be faster
372  *	  than writing into the main pool)
373  *	- the write occupies only one block
374  * WR_COPIED:
375  *    If we know we'll immediately be committing the
376  *    transaction (FSYNC or FDSYNC), the we allocate a larger
377  *    log record here for the data and copy the data in.
378  * WR_NEED_COPY:
379  *    Otherwise we don't allocate a buffer, and *if* we need to
380  *    flush the write later then a buffer is allocated and
381  *    we retrieve the data using the dmu.
382  */
383 typedef enum {
384 	WR_INDIRECT,	/* indirect - a large write (dmu_sync() data */
385 			/* and put blkptr in log, rather than actual data) */
386 	WR_COPIED,	/* immediate - data is copied into lr_write_t */
387 	WR_NEED_COPY,	/* immediate - data needs to be copied if pushed */
388 	WR_NUM_STATES	/* number of states */
389 } itx_wr_state_t;
390 
391 typedef struct itx {
392 	list_node_t	itx_node;	/* linkage on zl_itx_list */
393 	void		*itx_private;	/* type-specific opaque data */
394 	itx_wr_state_t	itx_wr_state;	/* write state */
395 	uint8_t		itx_sync;	/* synchronous transaction */
396 	uint64_t	itx_oid;	/* object id */
397 	lr_t		itx_lr;		/* common part of log record */
398 	/* followed by type-specific part of lr_xx_t and its immediate data */
399 } itx_t;
400 
401 typedef int zil_parse_blk_func_t(zilog_t *zilog, blkptr_t *bp, void *arg,
402     uint64_t txg);
403 typedef int zil_parse_lr_func_t(zilog_t *zilog, lr_t *lr, void *arg,
404     uint64_t txg);
405 typedef int zil_replay_func_t(void *arg1, void *arg2, boolean_t byteswap);
406 typedef int zil_get_data_t(void *arg, lr_write_t *lr, char *dbuf,
407     struct lwb *lwb, zio_t *zio);
408 
409 extern int zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func,
410     zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg);
411 
412 extern void	zil_init(void);
413 extern void	zil_fini(void);
414 
415 extern zilog_t	*zil_alloc(objset_t *os, zil_header_t *zh_phys);
416 extern void	zil_free(zilog_t *zilog);
417 
418 extern zilog_t	*zil_open(objset_t *os, zil_get_data_t *get_data);
419 extern void	zil_close(zilog_t *zilog);
420 
421 extern void	zil_replay(objset_t *os, void *arg,
422     zil_replay_func_t *replay_func[TX_MAX_TYPE]);
423 extern boolean_t zil_replaying(zilog_t *zilog, dmu_tx_t *tx);
424 extern void	zil_destroy(zilog_t *zilog, boolean_t keep_first);
425 extern void	zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx);
426 extern void	zil_rollback_destroy(zilog_t *zilog, dmu_tx_t *tx);
427 
428 extern itx_t	*zil_itx_create(uint64_t txtype, size_t lrsize);
429 extern void	zil_itx_destroy(itx_t *itx);
430 extern void	zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx);
431 
432 extern void	zil_commit(zilog_t *zilog, uint64_t oid);
433 extern void	zil_commit_impl(zilog_t *zilog, uint64_t oid);
434 
435 extern int	zil_reset(const char *osname, void *txarg);
436 extern int	zil_claim(struct dsl_pool *dp,
437     struct dsl_dataset *ds, void *txarg);
438 extern int	zil_check_log_chain(struct dsl_pool *dp,
439     struct dsl_dataset *ds, void *tx);
440 extern void	zil_sync(zilog_t *zilog, dmu_tx_t *tx);
441 extern void	zil_clean(zilog_t *zilog, uint64_t synced_txg);
442 
443 extern int	zil_suspend(const char *osname, void **cookiep);
444 extern void	zil_resume(void *cookie);
445 
446 extern void	zil_lwb_add_block(struct lwb *lwb, const blkptr_t *bp);
447 extern void	zil_lwb_add_txg(struct lwb *lwb, uint64_t txg);
448 extern int	zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp);
449 
450 extern void	zil_set_sync(zilog_t *zilog, uint64_t syncval);
451 
452 extern void	zil_set_logbias(zilog_t *zilog, uint64_t slogval);
453 
454 extern int zil_replay_disable;
455 
456 #ifdef	__cplusplus
457 }
458 #endif
459 
460 #endif	/* _SYS_ZIL_H */
461