xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/zil.h (revision ab3407e42869db06198054a02d468636f7b48bdb)
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 
44 /*
45  * Intent log format:
46  *
47  * Each objset has its own intent log.  The log header (zil_header_t)
48  * for objset N's intent log is kept in the Nth object of the SPA's
49  * intent_log objset.  The log header points to a chain of log blocks,
50  * each of which contains log records (i.e., transactions) followed by
51  * a log block trailer (zil_trailer_t).  The format of a log record
52  * depends on the record (or transaction) type, but all records begin
53  * with a common structure that defines the type, length, and txg.
54  */
55 
56 /*
57  * Intent log header - this on disk structure holds fields to manage
58  * the log.  All fields are 64 bit to easily handle cross architectures.
59  */
60 typedef struct zil_header {
61 	uint64_t zh_claim_txg;	/* txg in which log blocks were claimed */
62 	uint64_t zh_replay_seq;	/* highest replayed sequence number */
63 	blkptr_t zh_log;	/* log chain */
64 	uint64_t zh_claim_blk_seq; /* highest claimed block sequence number */
65 	uint64_t zh_flags;	/* header flags */
66 	uint64_t zh_claim_lr_seq; /* highest claimed lr sequence number */
67 	uint64_t zh_pad[3];
68 } zil_header_t;
69 
70 /*
71  * zh_flags bit settings
72  */
73 #define	ZIL_REPLAY_NEEDED	0x1	/* replay needed - internal only */
74 #define	ZIL_CLAIM_LR_SEQ_VALID	0x2	/* zh_claim_lr_seq field is valid */
75 
76 /*
77  * Log block chaining.
78  *
79  * Log blocks are chained together. Originally they were chained at the
80  * end of the block. For performance reasons the chain was moved to the
81  * beginning of the block which allows writes for only the data being used.
82  * The older position is supported for backwards compatability.
83  *
84  * The zio_eck_t contains a zec_cksum which for the intent log is
85  * the sequence number of this log block. A seq of 0 is invalid.
86  * The zec_cksum is checked by the SPA against the sequence
87  * number passed in the blk_cksum field of the blkptr_t
88  */
89 typedef struct zil_chain {
90 	uint64_t zc_pad;
91 	blkptr_t zc_next_blk;	/* next block in chain */
92 	uint64_t zc_nused;	/* bytes in log block used */
93 	zio_eck_t zc_eck;	/* block trailer */
94 } zil_chain_t;
95 
96 #define	ZIL_MIN_BLKSZ	4096ULL
97 
98 /*
99  * ziltest is by and large an ugly hack, but very useful in
100  * checking replay without tedious work.
101  * When running ziltest we want to keep all itx's and so maintain
102  * a single list in the zl_itxg[] that uses a high txg: ZILTEST_TXG
103  * We subtract TXG_CONCURRENT_STATES to allow for common code.
104  */
105 #define	ZILTEST_TXG (UINT64_MAX - TXG_CONCURRENT_STATES)
106 
107 /*
108  * The words of a log block checksum.
109  */
110 #define	ZIL_ZC_GUID_0	0
111 #define	ZIL_ZC_GUID_1	1
112 #define	ZIL_ZC_OBJSET	2
113 #define	ZIL_ZC_SEQ	3
114 
115 typedef enum zil_create {
116 	Z_FILE,
117 	Z_DIR,
118 	Z_XATTRDIR,
119 } zil_create_t;
120 
121 /*
122  * size of xvattr log section.
123  * its composed of lr_attr_t + xvattr bitmap + 2 64 bit timestamps
124  * for create time and a single 64 bit integer for all of the attributes,
125  * and 4 64 bit integers (32 bytes) for the scanstamp.
126  *
127  */
128 
129 #define	ZIL_XVAT_SIZE(mapsize) \
130 	sizeof (lr_attr_t) + (sizeof (uint32_t) * (mapsize - 1)) + \
131 	(sizeof (uint64_t) * 7)
132 
133 /*
134  * Size of ACL in log.  The ACE data is padded out to properly align
135  * on 8 byte boundary.
136  */
137 
138 #define	ZIL_ACE_LENGTH(x)	(roundup(x, sizeof (uint64_t)))
139 
140 /*
141  * Intent log transaction types and record structures
142  */
143 #define	TX_CREATE		1	/* Create file */
144 #define	TX_MKDIR		2	/* Make directory */
145 #define	TX_MKXATTR		3	/* Make XATTR directory */
146 #define	TX_SYMLINK		4	/* Create symbolic link to a file */
147 #define	TX_REMOVE		5	/* Remove file */
148 #define	TX_RMDIR		6	/* Remove directory */
149 #define	TX_LINK			7	/* Create hard link to a file */
150 #define	TX_RENAME		8	/* Rename a file */
151 #define	TX_WRITE		9	/* File write */
152 #define	TX_TRUNCATE		10	/* Truncate a file */
153 #define	TX_SETATTR		11	/* Set file attributes */
154 #define	TX_ACL_V0		12	/* Set old formatted ACL */
155 #define	TX_ACL			13	/* Set ACL */
156 #define	TX_CREATE_ACL		14	/* create with ACL */
157 #define	TX_CREATE_ATTR		15	/* create + attrs */
158 #define	TX_CREATE_ACL_ATTR 	16	/* create with ACL + attrs */
159 #define	TX_MKDIR_ACL		17	/* mkdir with ACL */
160 #define	TX_MKDIR_ATTR		18	/* mkdir with attr */
161 #define	TX_MKDIR_ACL_ATTR	19	/* mkdir with ACL + attrs */
162 #define	TX_WRITE2		20	/* dmu_sync EALREADY write */
163 #define	TX_MAX_TYPE		21	/* Max transaction type */
164 
165 /*
166  * The transactions for mkdir, symlink, remove, rmdir, link, and rename
167  * may have the following bit set, indicating the original request
168  * specified case-insensitive handling of names.
169  */
170 #define	TX_CI	((uint64_t)0x1 << 63) /* case-insensitive behavior requested */
171 
172 /*
173  * Transactions for write, truncate, setattr, acl_v0, and acl can be logged
174  * out of order.  For convenience in the code, all such records must have
175  * lr_foid at the same offset.
176  */
177 #define	TX_OOO(txtype)			\
178 	((txtype) == TX_WRITE ||	\
179 	(txtype) == TX_TRUNCATE ||	\
180 	(txtype) == TX_SETATTR ||	\
181 	(txtype) == TX_ACL_V0 ||	\
182 	(txtype) == TX_ACL ||		\
183 	(txtype) == TX_WRITE2)
184 
185 /*
186  * Format of log records.
187  * The fields are carefully defined to allow them to be aligned
188  * and sized the same on sparc & intel architectures.
189  * Each log record has a common structure at the beginning.
190  *
191  * The log record on disk (lrc_seq) holds the sequence number of all log
192  * records which is used to ensure we don't replay the same record.
193  */
194 typedef struct {			/* common log record header */
195 	uint64_t	lrc_txtype;	/* intent log transaction type */
196 	uint64_t	lrc_reclen;	/* transaction record length */
197 	uint64_t	lrc_txg;	/* dmu transaction group number */
198 	uint64_t	lrc_seq;	/* see comment above */
199 } lr_t;
200 
201 /*
202  * Common start of all out-of-order record types (TX_OOO() above).
203  */
204 typedef struct {
205 	lr_t		lr_common;	/* common portion of log record */
206 	uint64_t	lr_foid;	/* object id */
207 } lr_ooo_t;
208 
209 /*
210  * Handle option extended vattr attributes.
211  *
212  * Whenever new attributes are added the version number
213  * will need to be updated as will code in
214  * zfs_log.c and zfs_replay.c
215  */
216 typedef struct {
217 	uint32_t	lr_attr_masksize; /* number of elements in array */
218 	uint32_t	lr_attr_bitmap; /* First entry of array */
219 	/* remainder of array and any additional fields */
220 } lr_attr_t;
221 
222 /*
223  * log record for creates without optional ACL.
224  * This log record does support optional xvattr_t attributes.
225  */
226 typedef struct {
227 	lr_t		lr_common;	/* common portion of log record */
228 	uint64_t	lr_doid;	/* object id of directory */
229 	uint64_t	lr_foid;	/* object id of created file object */
230 	uint64_t	lr_mode;	/* mode of object */
231 	uint64_t	lr_uid;		/* uid of object */
232 	uint64_t	lr_gid;		/* gid of object */
233 	uint64_t	lr_gen;		/* generation (txg of creation) */
234 	uint64_t	lr_crtime[2];	/* creation time */
235 	uint64_t	lr_rdev;	/* rdev of object to create */
236 	/* name of object to create follows this */
237 	/* for symlinks, link content follows name */
238 	/* for creates with xvattr data, the name follows the xvattr info */
239 } lr_create_t;
240 
241 /*
242  * FUID ACL record will be an array of ACEs from the original ACL.
243  * If this array includes ephemeral IDs, the record will also include
244  * an array of log-specific FUIDs to replace the ephemeral IDs.
245  * Only one copy of each unique domain will be present, so the log-specific
246  * FUIDs will use an index into a compressed domain table.  On replay this
247  * information will be used to construct real FUIDs (and bypass idmap,
248  * since it may not be available).
249  */
250 
251 /*
252  * Log record for creates with optional ACL
253  * This log record is also used for recording any FUID
254  * information needed for replaying the create.  If the
255  * file doesn't have any actual ACEs then the lr_aclcnt
256  * would be zero.
257  *
258  * After lr_acl_flags, there are a lr_acl_bytes number of variable sized ace's.
259  * If create is also setting xvattr's, then acl data follows xvattr.
260  * If ACE FUIDs are needed then they will follow the xvattr_t.  Following
261  * the FUIDs will be the domain table information.  The FUIDs for the owner
262  * and group will be in lr_create.  Name follows ACL data.
263  */
264 typedef struct {
265 	lr_create_t	lr_create;	/* common create portion */
266 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
267 	uint64_t	lr_domcnt;	/* number of unique domains */
268 	uint64_t	lr_fuidcnt;	/* number of real fuids */
269 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
270 	uint64_t	lr_acl_flags;	/* ACL flags */
271 } lr_acl_create_t;
272 
273 typedef struct {
274 	lr_t		lr_common;	/* common portion of log record */
275 	uint64_t	lr_doid;	/* obj id of directory */
276 	/* name of object to remove follows this */
277 } lr_remove_t;
278 
279 typedef struct {
280 	lr_t		lr_common;	/* common portion of log record */
281 	uint64_t	lr_doid;	/* obj id of directory */
282 	uint64_t	lr_link_obj;	/* obj id of link */
283 	/* name of object to link follows this */
284 } lr_link_t;
285 
286 typedef struct {
287 	lr_t		lr_common;	/* common portion of log record */
288 	uint64_t	lr_sdoid;	/* obj id of source directory */
289 	uint64_t	lr_tdoid;	/* obj id of target directory */
290 	/* 2 strings: names of source and destination follow this */
291 } lr_rename_t;
292 
293 typedef struct {
294 	lr_t		lr_common;	/* common portion of log record */
295 	uint64_t	lr_foid;	/* file object to write */
296 	uint64_t	lr_offset;	/* offset to write to */
297 	uint64_t	lr_length;	/* user data length to write */
298 	uint64_t	lr_blkoff;	/* no longer used */
299 	blkptr_t	lr_blkptr;	/* spa block pointer for replay */
300 	/* write data will follow for small writes */
301 } lr_write_t;
302 
303 typedef struct {
304 	lr_t		lr_common;	/* common portion of log record */
305 	uint64_t	lr_foid;	/* object id of file to truncate */
306 	uint64_t	lr_offset;	/* offset to truncate from */
307 	uint64_t	lr_length;	/* length to truncate */
308 } lr_truncate_t;
309 
310 typedef struct {
311 	lr_t		lr_common;	/* common portion of log record */
312 	uint64_t	lr_foid;	/* file object to change attributes */
313 	uint64_t	lr_mask;	/* mask of attributes to set */
314 	uint64_t	lr_mode;	/* mode to set */
315 	uint64_t	lr_uid;		/* uid to set */
316 	uint64_t	lr_gid;		/* gid to set */
317 	uint64_t	lr_size;	/* size to set */
318 	uint64_t	lr_atime[2];	/* access time */
319 	uint64_t	lr_mtime[2];	/* modification time */
320 	/* optional attribute lr_attr_t may be here */
321 } lr_setattr_t;
322 
323 typedef struct {
324 	lr_t		lr_common;	/* common portion of log record */
325 	uint64_t	lr_foid;	/* obj id of file */
326 	uint64_t	lr_aclcnt;	/* number of acl entries */
327 	/* lr_aclcnt number of ace_t entries follow this */
328 } lr_acl_v0_t;
329 
330 typedef struct {
331 	lr_t		lr_common;	/* common portion of log record */
332 	uint64_t	lr_foid;	/* obj id of file */
333 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
334 	uint64_t	lr_domcnt;	/* number of unique domains */
335 	uint64_t	lr_fuidcnt;	/* number of real fuids */
336 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
337 	uint64_t	lr_acl_flags;	/* ACL flags */
338 	/* lr_acl_bytes number of variable sized ace's follows */
339 } lr_acl_t;
340 
341 /*
342  * ZIL structure definitions, interface function prototype and globals.
343  */
344 
345 /*
346  * Writes are handled in three different ways:
347  *
348  * WR_INDIRECT:
349  *    In this mode, if we need to commit the write later, then the block
350  *    is immediately written into the file system (using dmu_sync),
351  *    and a pointer to the block is put into the log record.
352  *    When the txg commits the block is linked in.
353  *    This saves additionally writing the data into the log record.
354  *    There are a few requirements for this to occur:
355  *	- write is greater than zfs/zvol_immediate_write_sz
356  *	- not using slogs (as slogs are assumed to always be faster
357  *	  than writing into the main pool)
358  *	- the write occupies only one block
359  * WR_COPIED:
360  *    If we know we'll immediately be committing the
361  *    transaction (FSYNC or FDSYNC), the we allocate a larger
362  *    log record here for the data and copy the data in.
363  * WR_NEED_COPY:
364  *    Otherwise we don't allocate a buffer, and *if* we need to
365  *    flush the write later then a buffer is allocated and
366  *    we retrieve the data using the dmu.
367  */
368 typedef enum {
369 	WR_INDIRECT,	/* indirect - a large write (dmu_sync() data */
370 			/* and put blkptr in log, rather than actual data) */
371 	WR_COPIED,	/* immediate - data is copied into lr_write_t */
372 	WR_NEED_COPY,	/* immediate - data needs to be copied if pushed */
373 	WR_NUM_STATES	/* number of states */
374 } itx_wr_state_t;
375 
376 typedef struct itx {
377 	list_node_t	itx_node;	/* linkage on zl_itx_list */
378 	void		*itx_private;	/* type-specific opaque data */
379 	itx_wr_state_t	itx_wr_state;	/* write state */
380 	uint8_t		itx_sync;	/* synchronous transaction */
381 	uint64_t	itx_sod;	/* record size on disk */
382 	uint64_t	itx_oid;	/* object id */
383 	lr_t		itx_lr;		/* common part of log record */
384 	/* followed by type-specific part of lr_xx_t and its immediate data */
385 } itx_t;
386 
387 typedef int zil_parse_blk_func_t(zilog_t *zilog, blkptr_t *bp, void *arg,
388     uint64_t txg);
389 typedef int zil_parse_lr_func_t(zilog_t *zilog, lr_t *lr, void *arg,
390     uint64_t txg);
391 typedef int zil_replay_func_t();
392 typedef int zil_get_data_t(void *arg, lr_write_t *lr, char *dbuf, zio_t *zio);
393 
394 extern int zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func,
395     zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg);
396 
397 extern void	zil_init(void);
398 extern void	zil_fini(void);
399 
400 extern zilog_t	*zil_alloc(objset_t *os, zil_header_t *zh_phys);
401 extern void	zil_free(zilog_t *zilog);
402 
403 extern zilog_t	*zil_open(objset_t *os, zil_get_data_t *get_data);
404 extern void	zil_close(zilog_t *zilog);
405 
406 extern void	zil_replay(objset_t *os, void *arg,
407     zil_replay_func_t *replay_func[TX_MAX_TYPE]);
408 extern boolean_t zil_replaying(zilog_t *zilog, dmu_tx_t *tx);
409 extern void	zil_destroy(zilog_t *zilog, boolean_t keep_first);
410 extern void	zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx);
411 extern void	zil_rollback_destroy(zilog_t *zilog, dmu_tx_t *tx);
412 
413 extern itx_t	*zil_itx_create(uint64_t txtype, size_t lrsize);
414 extern void	zil_itx_destroy(itx_t *itx);
415 extern void	zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx);
416 
417 extern void	zil_commit(zilog_t *zilog, uint64_t oid);
418 
419 extern int	zil_vdev_offline(const char *osname, void *txarg);
420 extern int	zil_claim(struct dsl_pool *dp,
421     struct dsl_dataset *ds, void *txarg);
422 extern int 	zil_check_log_chain(struct dsl_pool *dp,
423     struct dsl_dataset *ds, void *tx);
424 extern void	zil_sync(zilog_t *zilog, dmu_tx_t *tx);
425 extern void	zil_clean(zilog_t *zilog, uint64_t synced_txg);
426 
427 extern int	zil_suspend(const char *osname, void **cookiep);
428 extern void	zil_resume(void *cookie);
429 
430 extern void	zil_add_block(zilog_t *zilog, const blkptr_t *bp);
431 extern int	zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp);
432 
433 extern void	zil_set_sync(zilog_t *zilog, uint64_t syncval);
434 
435 extern void	zil_set_logbias(zilog_t *zilog, uint64_t slogval);
436 
437 extern int zil_replay_disable;
438 
439 #ifdef	__cplusplus
440 }
441 #endif
442 
443 #endif	/* _SYS_ZIL_H */
444