xref: /titanic_52/usr/src/uts/common/fs/zfs/sys/zil.h (revision b49b27dcb66b2c7f4a23f7bc158e2dde5cd79030)
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 by Delphix. All rights reserved.
24  */
25 
26 /* Portions Copyright 2010 Robert Milkowski */
27 
28 #ifndef	_SYS_ZIL_H
29 #define	_SYS_ZIL_H
30 
31 #include <sys/types.h>
32 #include <sys/spa.h>
33 #include <sys/zio.h>
34 #include <sys/dmu.h>
35 
36 #ifdef	__cplusplus
37 extern "C" {
38 #endif
39 
40 /*
41  * Intent log format:
42  *
43  * Each objset has its own intent log.  The log header (zil_header_t)
44  * for objset N's intent log is kept in the Nth object of the SPA's
45  * intent_log objset.  The log header points to a chain of log blocks,
46  * each of which contains log records (i.e., transactions) followed by
47  * a log block trailer (zil_trailer_t).  The format of a log record
48  * depends on the record (or transaction) type, but all records begin
49  * with a common structure that defines the type, length, and txg.
50  */
51 
52 /*
53  * Intent log header - this on disk structure holds fields to manage
54  * the log.  All fields are 64 bit to easily handle cross architectures.
55  */
56 typedef struct zil_header {
57 	uint64_t zh_claim_txg;	/* txg in which log blocks were claimed */
58 	uint64_t zh_replay_seq;	/* highest replayed sequence number */
59 	blkptr_t zh_log;	/* log chain */
60 	uint64_t zh_claim_blk_seq; /* highest claimed block sequence number */
61 	uint64_t zh_flags;	/* header flags */
62 	uint64_t zh_claim_lr_seq; /* highest claimed lr sequence number */
63 	uint64_t zh_pad[3];
64 } zil_header_t;
65 
66 /*
67  * zh_flags bit settings
68  */
69 #define	ZIL_REPLAY_NEEDED	0x1	/* replay needed - internal only */
70 #define	ZIL_CLAIM_LR_SEQ_VALID	0x2	/* zh_claim_lr_seq field is valid */
71 
72 /*
73  * Log block chaining.
74  *
75  * Log blocks are chained together. Originally they were chained at the
76  * end of the block. For performance reasons the chain was moved to the
77  * beginning of the block which allows writes for only the data being used.
78  * The older position is supported for backwards compatability.
79  *
80  * The zio_eck_t contains a zec_cksum which for the intent log is
81  * the sequence number of this log block. A seq of 0 is invalid.
82  * The zec_cksum is checked by the SPA against the sequence
83  * number passed in the blk_cksum field of the blkptr_t
84  */
85 typedef struct zil_chain {
86 	uint64_t zc_pad;
87 	blkptr_t zc_next_blk;	/* next block in chain */
88 	uint64_t zc_nused;	/* bytes in log block used */
89 	zio_eck_t zc_eck;	/* block trailer */
90 } zil_chain_t;
91 
92 #define	ZIL_MIN_BLKSZ	4096ULL
93 #define	ZIL_MAX_BLKSZ	SPA_MAXBLOCKSIZE
94 
95 /*
96  * The words of a log block checksum.
97  */
98 #define	ZIL_ZC_GUID_0	0
99 #define	ZIL_ZC_GUID_1	1
100 #define	ZIL_ZC_OBJSET	2
101 #define	ZIL_ZC_SEQ	3
102 
103 typedef enum zil_create {
104 	Z_FILE,
105 	Z_DIR,
106 	Z_XATTRDIR,
107 } zil_create_t;
108 
109 /*
110  * size of xvattr log section.
111  * its composed of lr_attr_t + xvattr bitmap + 2 64 bit timestamps
112  * for create time and a single 64 bit integer for all of the attributes,
113  * and 4 64 bit integers (32 bytes) for the scanstamp.
114  *
115  */
116 
117 #define	ZIL_XVAT_SIZE(mapsize) \
118 	sizeof (lr_attr_t) + (sizeof (uint32_t) * (mapsize - 1)) + \
119 	(sizeof (uint64_t) * 7)
120 
121 /*
122  * Size of ACL in log.  The ACE data is padded out to properly align
123  * on 8 byte boundary.
124  */
125 
126 #define	ZIL_ACE_LENGTH(x)	(roundup(x, sizeof (uint64_t)))
127 
128 /*
129  * Intent log transaction types and record structures
130  */
131 #define	TX_CREATE		1	/* Create file */
132 #define	TX_MKDIR		2	/* Make directory */
133 #define	TX_MKXATTR		3	/* Make XATTR directory */
134 #define	TX_SYMLINK		4	/* Create symbolic link to a file */
135 #define	TX_REMOVE		5	/* Remove file */
136 #define	TX_RMDIR		6	/* Remove directory */
137 #define	TX_LINK			7	/* Create hard link to a file */
138 #define	TX_RENAME		8	/* Rename a file */
139 #define	TX_WRITE		9	/* File write */
140 #define	TX_TRUNCATE		10	/* Truncate a file */
141 #define	TX_SETATTR		11	/* Set file attributes */
142 #define	TX_ACL_V0		12	/* Set old formatted ACL */
143 #define	TX_ACL			13	/* Set ACL */
144 #define	TX_CREATE_ACL		14	/* create with ACL */
145 #define	TX_CREATE_ATTR		15	/* create + attrs */
146 #define	TX_CREATE_ACL_ATTR 	16	/* create with ACL + attrs */
147 #define	TX_MKDIR_ACL		17	/* mkdir with ACL */
148 #define	TX_MKDIR_ATTR		18	/* mkdir with attr */
149 #define	TX_MKDIR_ACL_ATTR	19	/* mkdir with ACL + attrs */
150 #define	TX_WRITE2		20	/* dmu_sync EALREADY write */
151 #define	TX_MAX_TYPE		21	/* Max transaction type */
152 
153 /*
154  * The transactions for mkdir, symlink, remove, rmdir, link, and rename
155  * may have the following bit set, indicating the original request
156  * specified case-insensitive handling of names.
157  */
158 #define	TX_CI	((uint64_t)0x1 << 63) /* case-insensitive behavior requested */
159 
160 /*
161  * Transactions for write, truncate, setattr, acl_v0, and acl can be logged
162  * out of order.  For convenience in the code, all such records must have
163  * lr_foid at the same offset.
164  */
165 #define	TX_OOO(txtype)			\
166 	((txtype) == TX_WRITE ||	\
167 	(txtype) == TX_TRUNCATE ||	\
168 	(txtype) == TX_SETATTR ||	\
169 	(txtype) == TX_ACL_V0 ||	\
170 	(txtype) == TX_ACL ||		\
171 	(txtype) == TX_WRITE2)
172 
173 /*
174  * Format of log records.
175  * The fields are carefully defined to allow them to be aligned
176  * and sized the same on sparc & intel architectures.
177  * Each log record has a common structure at the beginning.
178  *
179  * The log record on disk (lrc_seq) holds the sequence number of all log
180  * records which is used to ensure we don't replay the same record.
181  */
182 typedef struct {			/* common log record header */
183 	uint64_t	lrc_txtype;	/* intent log transaction type */
184 	uint64_t	lrc_reclen;	/* transaction record length */
185 	uint64_t	lrc_txg;	/* dmu transaction group number */
186 	uint64_t	lrc_seq;	/* see comment above */
187 } lr_t;
188 
189 /*
190  * Common start of all out-of-order record types (TX_OOO() above).
191  */
192 typedef struct {
193 	lr_t		lr_common;	/* common portion of log record */
194 	uint64_t	lr_foid;	/* object id */
195 } lr_ooo_t;
196 
197 /*
198  * Handle option extended vattr attributes.
199  *
200  * Whenever new attributes are added the version number
201  * will need to be updated as will code in
202  * zfs_log.c and zfs_replay.c
203  */
204 typedef struct {
205 	uint32_t	lr_attr_masksize; /* number of elements in array */
206 	uint32_t	lr_attr_bitmap; /* First entry of array */
207 	/* remainder of array and any additional fields */
208 } lr_attr_t;
209 
210 /*
211  * log record for creates without optional ACL.
212  * This log record does support optional xvattr_t attributes.
213  */
214 typedef struct {
215 	lr_t		lr_common;	/* common portion of log record */
216 	uint64_t	lr_doid;	/* object id of directory */
217 	uint64_t	lr_foid;	/* object id of created file object */
218 	uint64_t	lr_mode;	/* mode of object */
219 	uint64_t	lr_uid;		/* uid of object */
220 	uint64_t	lr_gid;		/* gid of object */
221 	uint64_t	lr_gen;		/* generation (txg of creation) */
222 	uint64_t	lr_crtime[2];	/* creation time */
223 	uint64_t	lr_rdev;	/* rdev of object to create */
224 	/* name of object to create follows this */
225 	/* for symlinks, link content follows name */
226 	/* for creates with xvattr data, the name follows the xvattr info */
227 } lr_create_t;
228 
229 /*
230  * FUID ACL record will be an array of ACEs from the original ACL.
231  * If this array includes ephemeral IDs, the record will also include
232  * an array of log-specific FUIDs to replace the ephemeral IDs.
233  * Only one copy of each unique domain will be present, so the log-specific
234  * FUIDs will use an index into a compressed domain table.  On replay this
235  * information will be used to construct real FUIDs (and bypass idmap,
236  * since it may not be available).
237  */
238 
239 /*
240  * Log record for creates with optional ACL
241  * This log record is also used for recording any FUID
242  * information needed for replaying the create.  If the
243  * file doesn't have any actual ACEs then the lr_aclcnt
244  * would be zero.
245  *
246  * After lr_acl_flags, there are a lr_acl_bytes number of variable sized ace's.
247  * If create is also setting xvattr's, then acl data follows xvattr.
248  * If ACE FUIDs are needed then they will follow the xvattr_t.  Following
249  * the FUIDs will be the domain table information.  The FUIDs for the owner
250  * and group will be in lr_create.  Name follows ACL data.
251  */
252 typedef struct {
253 	lr_create_t	lr_create;	/* common create portion */
254 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
255 	uint64_t	lr_domcnt;	/* number of unique domains */
256 	uint64_t	lr_fuidcnt;	/* number of real fuids */
257 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
258 	uint64_t	lr_acl_flags;	/* ACL flags */
259 } lr_acl_create_t;
260 
261 typedef struct {
262 	lr_t		lr_common;	/* common portion of log record */
263 	uint64_t	lr_doid;	/* obj id of directory */
264 	/* name of object to remove follows this */
265 } lr_remove_t;
266 
267 typedef struct {
268 	lr_t		lr_common;	/* common portion of log record */
269 	uint64_t	lr_doid;	/* obj id of directory */
270 	uint64_t	lr_link_obj;	/* obj id of link */
271 	/* name of object to link follows this */
272 } lr_link_t;
273 
274 typedef struct {
275 	lr_t		lr_common;	/* common portion of log record */
276 	uint64_t	lr_sdoid;	/* obj id of source directory */
277 	uint64_t	lr_tdoid;	/* obj id of target directory */
278 	/* 2 strings: names of source and destination follow this */
279 } lr_rename_t;
280 
281 typedef struct {
282 	lr_t		lr_common;	/* common portion of log record */
283 	uint64_t	lr_foid;	/* file object to write */
284 	uint64_t	lr_offset;	/* offset to write to */
285 	uint64_t	lr_length;	/* user data length to write */
286 	uint64_t	lr_blkoff;	/* no longer used */
287 	blkptr_t	lr_blkptr;	/* spa block pointer for replay */
288 	/* write data will follow for small writes */
289 } lr_write_t;
290 
291 typedef struct {
292 	lr_t		lr_common;	/* common portion of log record */
293 	uint64_t	lr_foid;	/* object id of file to truncate */
294 	uint64_t	lr_offset;	/* offset to truncate from */
295 	uint64_t	lr_length;	/* length to truncate */
296 } lr_truncate_t;
297 
298 typedef struct {
299 	lr_t		lr_common;	/* common portion of log record */
300 	uint64_t	lr_foid;	/* file object to change attributes */
301 	uint64_t	lr_mask;	/* mask of attributes to set */
302 	uint64_t	lr_mode;	/* mode to set */
303 	uint64_t	lr_uid;		/* uid to set */
304 	uint64_t	lr_gid;		/* gid to set */
305 	uint64_t	lr_size;	/* size to set */
306 	uint64_t	lr_atime[2];	/* access time */
307 	uint64_t	lr_mtime[2];	/* modification time */
308 	/* optional attribute lr_attr_t may be here */
309 } lr_setattr_t;
310 
311 typedef struct {
312 	lr_t		lr_common;	/* common portion of log record */
313 	uint64_t	lr_foid;	/* obj id of file */
314 	uint64_t	lr_aclcnt;	/* number of acl entries */
315 	/* lr_aclcnt number of ace_t entries follow this */
316 } lr_acl_v0_t;
317 
318 typedef struct {
319 	lr_t		lr_common;	/* common portion of log record */
320 	uint64_t	lr_foid;	/* obj id of file */
321 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
322 	uint64_t	lr_domcnt;	/* number of unique domains */
323 	uint64_t	lr_fuidcnt;	/* number of real fuids */
324 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
325 	uint64_t	lr_acl_flags;	/* ACL flags */
326 	/* lr_acl_bytes number of variable sized ace's follows */
327 } lr_acl_t;
328 
329 /*
330  * ZIL structure definitions, interface function prototype and globals.
331  */
332 
333 /*
334  * Writes are handled in three different ways:
335  *
336  * WR_INDIRECT:
337  *    In this mode, if we need to commit the write later, then the block
338  *    is immediately written into the file system (using dmu_sync),
339  *    and a pointer to the block is put into the log record.
340  *    When the txg commits the block is linked in.
341  *    This saves additionally writing the data into the log record.
342  *    There are a few requirements for this to occur:
343  *	- write is greater than zfs/zvol_immediate_write_sz
344  *	- not using slogs (as slogs are assumed to always be faster
345  *	  than writing into the main pool)
346  *	- the write occupies only one block
347  * WR_COPIED:
348  *    If we know we'll immediately be committing the
349  *    transaction (FSYNC or FDSYNC), the we allocate a larger
350  *    log record here for the data and copy the data in.
351  * WR_NEED_COPY:
352  *    Otherwise we don't allocate a buffer, and *if* we need to
353  *    flush the write later then a buffer is allocated and
354  *    we retrieve the data using the dmu.
355  */
356 typedef enum {
357 	WR_INDIRECT,	/* indirect - a large write (dmu_sync() data */
358 			/* and put blkptr in log, rather than actual data) */
359 	WR_COPIED,	/* immediate - data is copied into lr_write_t */
360 	WR_NEED_COPY,	/* immediate - data needs to be copied if pushed */
361 	WR_NUM_STATES	/* number of states */
362 } itx_wr_state_t;
363 
364 typedef struct itx {
365 	list_node_t	itx_node;	/* linkage on zl_itx_list */
366 	void		*itx_private;	/* type-specific opaque data */
367 	itx_wr_state_t	itx_wr_state;	/* write state */
368 	uint8_t		itx_sync;	/* synchronous transaction */
369 	uint64_t	itx_sod;	/* record size on disk */
370 	uint64_t	itx_oid;	/* object id */
371 	lr_t		itx_lr;		/* common part of log record */
372 	/* followed by type-specific part of lr_xx_t and its immediate data */
373 } itx_t;
374 
375 typedef int zil_parse_blk_func_t(zilog_t *zilog, blkptr_t *bp, void *arg,
376     uint64_t txg);
377 typedef int zil_parse_lr_func_t(zilog_t *zilog, lr_t *lr, void *arg,
378     uint64_t txg);
379 typedef int zil_replay_func_t();
380 typedef int zil_get_data_t(void *arg, lr_write_t *lr, char *dbuf, zio_t *zio);
381 
382 extern int zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func,
383     zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg);
384 
385 extern void	zil_init(void);
386 extern void	zil_fini(void);
387 
388 extern zilog_t	*zil_alloc(objset_t *os, zil_header_t *zh_phys);
389 extern void	zil_free(zilog_t *zilog);
390 
391 extern zilog_t	*zil_open(objset_t *os, zil_get_data_t *get_data);
392 extern void	zil_close(zilog_t *zilog);
393 
394 extern void	zil_replay(objset_t *os, void *arg,
395     zil_replay_func_t *replay_func[TX_MAX_TYPE]);
396 extern boolean_t zil_replaying(zilog_t *zilog, dmu_tx_t *tx);
397 extern void	zil_destroy(zilog_t *zilog, boolean_t keep_first);
398 extern void	zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx);
399 extern void	zil_rollback_destroy(zilog_t *zilog, dmu_tx_t *tx);
400 
401 extern itx_t	*zil_itx_create(uint64_t txtype, size_t lrsize);
402 extern void	zil_itx_destroy(itx_t *itx);
403 extern void	zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx);
404 
405 extern void	zil_commit(zilog_t *zilog, uint64_t oid);
406 
407 extern int	zil_vdev_offline(const char *osname, void *txarg);
408 extern int	zil_claim(const char *osname, void *txarg);
409 extern int	zil_check_log_chain(const char *osname, void *txarg);
410 extern void	zil_sync(zilog_t *zilog, dmu_tx_t *tx);
411 extern void	zil_clean(zilog_t *zilog, uint64_t synced_txg);
412 
413 extern int	zil_suspend(const char *osname, void **cookiep);
414 extern void	zil_resume(void *cookie);
415 
416 extern void	zil_add_block(zilog_t *zilog, const blkptr_t *bp);
417 extern int	zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp);
418 
419 extern void	zil_set_sync(zilog_t *zilog, uint64_t syncval);
420 
421 extern void	zil_set_logbias(zilog_t *zilog, uint64_t slogval);
422 
423 extern int zil_replay_disable;
424 
425 #ifdef	__cplusplus
426 }
427 #endif
428 
429 #endif	/* _SYS_ZIL_H */
430