xref: /titanic_41/usr/src/uts/common/fs/zfs/sys/zil.h (revision 9e39c5ba00a55fa05777cc94b148296af305e135)
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 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef	_SYS_ZIL_H
27 #define	_SYS_ZIL_H
28 
29 #include <sys/types.h>
30 #include <sys/spa.h>
31 #include <sys/zio.h>
32 #include <sys/dmu.h>
33 
34 #ifdef	__cplusplus
35 extern "C" {
36 #endif
37 
38 /*
39  * Intent log format:
40  *
41  * Each objset has its own intent log.  The log header (zil_header_t)
42  * for objset N's intent log is kept in the Nth object of the SPA's
43  * intent_log objset.  The log header points to a chain of log blocks,
44  * each of which contains log records (i.e., transactions) followed by
45  * a log block trailer (zil_trailer_t).  The format of a log record
46  * depends on the record (or transaction) type, but all records begin
47  * with a common structure that defines the type, length, and txg.
48  */
49 
50 /*
51  * Intent log header - this on disk structure holds fields to manage
52  * the log.  All fields are 64 bit to easily handle cross architectures.
53  */
54 typedef struct zil_header {
55 	uint64_t zh_claim_txg;	/* txg in which log blocks were claimed */
56 	uint64_t zh_replay_seq;	/* highest replayed sequence number */
57 	blkptr_t zh_log;	/* log chain */
58 	uint64_t zh_claim_seq;	/* highest claimed sequence number */
59 	uint64_t zh_flags;	/* header flags */
60 	uint64_t zh_pad[4];
61 } zil_header_t;
62 
63 /*
64  * zh_flags bit settings
65  */
66 #define	ZIL_REPLAY_NEEDED 0x1	/* replay needed - internal only */
67 
68 /*
69  * Log block trailer - structure at the end of the header and each log block
70  *
71  * The zit_bt contains a zbt_cksum which for the intent log is
72  * the sequence number of this log block. A seq of 0 is invalid.
73  * The zbt_cksum is checked by the SPA against the sequence
74  * number passed in the blk_cksum field of the blkptr_t
75  */
76 typedef struct zil_trailer {
77 	uint64_t zit_pad;
78 	blkptr_t zit_next_blk;	/* next block in chain */
79 	uint64_t zit_nused;	/* bytes in log block used */
80 	zio_block_tail_t zit_bt; /* block trailer */
81 } zil_trailer_t;
82 
83 #define	ZIL_MIN_BLKSZ	4096ULL
84 #define	ZIL_MAX_BLKSZ	SPA_MAXBLOCKSIZE
85 #define	ZIL_BLK_DATA_SZ(lwb)	((lwb)->lwb_sz - sizeof (zil_trailer_t))
86 
87 /*
88  * The words of a log block checksum.
89  */
90 #define	ZIL_ZC_GUID_0	0
91 #define	ZIL_ZC_GUID_1	1
92 #define	ZIL_ZC_OBJSET	2
93 #define	ZIL_ZC_SEQ	3
94 
95 typedef enum zil_create {
96 	Z_FILE,
97 	Z_DIR,
98 	Z_XATTRDIR,
99 } zil_create_t;
100 
101 /*
102  * size of xvattr log section.
103  * its composed of lr_attr_t + xvattr bitmap + 2 64 bit timestamps
104  * for create time and a single 64 bit integer for all of the attributes,
105  * and 4 64 bit integers (32 bytes) for the scanstamp.
106  *
107  */
108 
109 #define	ZIL_XVAT_SIZE(mapsize) \
110 	sizeof (lr_attr_t) + (sizeof (uint32_t) * (mapsize - 1)) + \
111 	(sizeof (uint64_t) * 7)
112 
113 /*
114  * Size of ACL in log.  The ACE data is padded out to properly align
115  * on 8 byte boundary.
116  */
117 
118 #define	ZIL_ACE_LENGTH(x)	(roundup(x, sizeof (uint64_t)))
119 
120 /*
121  * Intent log transaction types and record structures
122  */
123 #define	TX_CREATE		1	/* Create file */
124 #define	TX_MKDIR		2	/* Make directory */
125 #define	TX_MKXATTR		3	/* Make XATTR directory */
126 #define	TX_SYMLINK		4	/* Create symbolic link to a file */
127 #define	TX_REMOVE		5	/* Remove file */
128 #define	TX_RMDIR		6	/* Remove directory */
129 #define	TX_LINK			7	/* Create hard link to a file */
130 #define	TX_RENAME		8	/* Rename a file */
131 #define	TX_WRITE		9	/* File write */
132 #define	TX_TRUNCATE		10	/* Truncate a file */
133 #define	TX_SETATTR		11	/* Set file attributes */
134 #define	TX_ACL_V0		12	/* Set old formatted ACL */
135 #define	TX_ACL			13	/* Set ACL */
136 #define	TX_CREATE_ACL		14	/* create with ACL */
137 #define	TX_CREATE_ATTR		15	/* create + attrs */
138 #define	TX_CREATE_ACL_ATTR 	16	/* create with ACL + attrs */
139 #define	TX_MKDIR_ACL		17	/* mkdir with ACL */
140 #define	TX_MKDIR_ATTR		18	/* mkdir with attr */
141 #define	TX_MKDIR_ACL_ATTR	19	/* mkdir with ACL + attrs */
142 #define	TX_MAX_TYPE		20	/* Max transaction type */
143 
144 /*
145  * The transactions for mkdir, symlink, remove, rmdir, link, and rename
146  * may have the following bit set, indicating the original request
147  * specified case-insensitive handling of names.
148  */
149 #define	TX_CI	((uint64_t)0x1 << 63) /* case-insensitive behavior requested */
150 
151 /*
152  * Format of log records.
153  * The fields are carefully defined to allow them to be aligned
154  * and sized the same on sparc & intel architectures.
155  * Each log record has a common structure at the beginning.
156  *
157  * Note, lrc_seq holds two different sequence numbers. Whilst in memory
158  * it contains the transaction sequence number.  The log record on
159  * disk holds the sequence number of all log records which is used to
160  * ensure we don't replay the same record.  The two sequence numbers are
161  * different because the transactions can now be pushed out of order.
162  */
163 typedef struct {			/* common log record header */
164 	uint64_t	lrc_txtype;	/* intent log transaction type */
165 	uint64_t	lrc_reclen;	/* transaction record length */
166 	uint64_t	lrc_txg;	/* dmu transaction group number */
167 	uint64_t	lrc_seq;	/* see comment above */
168 } lr_t;
169 
170 /*
171  * Handle option extended vattr attributes.
172  *
173  * Whenever new attributes are added the version number
174  * will need to be updated as will code in
175  * zfs_log.c and zfs_replay.c
176  */
177 typedef struct {
178 	uint32_t	lr_attr_masksize; /* number of elements in array */
179 	uint32_t	lr_attr_bitmap; /* First entry of array */
180 	/* remainder of array and any additional fields */
181 } lr_attr_t;
182 
183 /*
184  * log record for creates without optional ACL.
185  * This log record does support optional xvattr_t attributes.
186  */
187 typedef struct {
188 	lr_t		lr_common;	/* common portion of log record */
189 	uint64_t	lr_doid;	/* object id of directory */
190 	uint64_t	lr_foid;	/* object id of created file object */
191 	uint64_t	lr_mode;	/* mode of object */
192 	uint64_t	lr_uid;		/* uid of object */
193 	uint64_t	lr_gid;		/* gid of object */
194 	uint64_t	lr_gen;		/* generation (txg of creation) */
195 	uint64_t	lr_crtime[2];	/* creation time */
196 	uint64_t	lr_rdev;	/* rdev of object to create */
197 	/* name of object to create follows this */
198 	/* for symlinks, link content follows name */
199 	/* for creates with xvattr data, the name follows the xvattr info */
200 } lr_create_t;
201 
202 /*
203  * FUID ACL record will be an array of ACEs from the original ACL.
204  * If this array includes ephemeral IDs, the record will also include
205  * an array of log-specific FUIDs to replace the ephemeral IDs.
206  * Only one copy of each unique domain will be present, so the log-specific
207  * FUIDs will use an index into a compressed domain table.  On replay this
208  * information will be used to construct real FUIDs (and bypass idmap,
209  * since it may not be available).
210  */
211 
212 /*
213  * Log record for creates with optional ACL
214  * This log record is also used for recording any FUID
215  * information needed for replaying the create.  If the
216  * file doesn't have any actual ACEs then the lr_aclcnt
217  * would be zero.
218  */
219 typedef struct {
220 	lr_create_t	lr_create;	/* common create portion */
221 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
222 	uint64_t	lr_domcnt;	/* number of unique domains */
223 	uint64_t	lr_fuidcnt;	/* number of real fuids */
224 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
225 	uint64_t	lr_acl_flags;	/* ACL flags */
226 	/* lr_acl_bytes number of variable sized ace's follows */
227 	/* if create is also setting xvattr's, then acl data follows xvattr */
228 	/* if ACE FUIDs are needed then they will follow the xvattr_t */
229 	/* Following the FUIDs will be the domain table information. */
230 	/* The FUIDs for the owner and group will be in the lr_create */
231 	/* portion of the record. */
232 	/* name follows ACL data */
233 } lr_acl_create_t;
234 
235 typedef struct {
236 	lr_t		lr_common;	/* common portion of log record */
237 	uint64_t	lr_doid;	/* obj id of directory */
238 	/* name of object to remove follows this */
239 } lr_remove_t;
240 
241 typedef struct {
242 	lr_t		lr_common;	/* common portion of log record */
243 	uint64_t	lr_doid;	/* obj id of directory */
244 	uint64_t	lr_link_obj;	/* obj id of link */
245 	/* name of object to link follows this */
246 } lr_link_t;
247 
248 typedef struct {
249 	lr_t		lr_common;	/* common portion of log record */
250 	uint64_t	lr_sdoid;	/* obj id of source directory */
251 	uint64_t	lr_tdoid;	/* obj id of target directory */
252 	/* 2 strings: names of source and destination follow this */
253 } lr_rename_t;
254 
255 typedef struct {
256 	lr_t		lr_common;	/* common portion of log record */
257 	uint64_t	lr_foid;	/* file object to write */
258 	uint64_t	lr_offset;	/* offset to write to */
259 	uint64_t	lr_length;	/* user data length to write */
260 	uint64_t	lr_blkoff;	/* offset represented by lr_blkptr */
261 	blkptr_t	lr_blkptr;	/* spa block pointer for replay */
262 	/* write data will follow for small writes */
263 } lr_write_t;
264 
265 typedef struct {
266 	lr_t		lr_common;	/* common portion of log record */
267 	uint64_t	lr_foid;	/* object id of file to truncate */
268 	uint64_t	lr_offset;	/* offset to truncate from */
269 	uint64_t	lr_length;	/* length to truncate */
270 } lr_truncate_t;
271 
272 typedef struct {
273 	lr_t		lr_common;	/* common portion of log record */
274 	uint64_t	lr_foid;	/* file object to change attributes */
275 	uint64_t	lr_mask;	/* mask of attributes to set */
276 	uint64_t	lr_mode;	/* mode to set */
277 	uint64_t	lr_uid;		/* uid to set */
278 	uint64_t	lr_gid;		/* gid to set */
279 	uint64_t	lr_size;	/* size to set */
280 	uint64_t	lr_atime[2];	/* access time */
281 	uint64_t	lr_mtime[2];	/* modification time */
282 	/* optional attribute lr_attr_t may be here */
283 } lr_setattr_t;
284 
285 typedef struct {
286 	lr_t		lr_common;	/* common portion of log record */
287 	uint64_t	lr_foid;	/* obj id of file */
288 	uint64_t	lr_aclcnt;	/* number of acl entries */
289 	/* lr_aclcnt number of ace_t entries follow this */
290 } lr_acl_v0_t;
291 
292 typedef struct {
293 	lr_t		lr_common;	/* common portion of log record */
294 	uint64_t	lr_foid;	/* obj id of file */
295 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
296 	uint64_t	lr_domcnt;	/* number of unique domains */
297 	uint64_t	lr_fuidcnt;	/* number of real fuids */
298 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
299 	uint64_t	lr_acl_flags;	/* ACL flags */
300 	/* lr_acl_bytes number of variable sized ace's follows */
301 } lr_acl_t;
302 
303 /*
304  * ZIL structure definitions, interface function prototype and globals.
305  */
306 
307 /*
308  * Writes are handled in three different ways:
309  *
310  * WR_INDIRECT:
311  *    In this mode, if we need to commit the write later, then the block
312  *    is immediately written into the file system (using dmu_sync),
313  *    and a pointer to the block is put into the log record.
314  *    When the txg commits the block is linked in.
315  *    This saves additionally writing the data into the log record.
316  *    There are a few requirements for this to occur:
317  *	- write is greater than zfs/zvol_immediate_write_sz
318  *	- not using slogs (as slogs are assumed to always be faster
319  *	  than writing into the main pool)
320  *	- the write occupies only one block
321  * WR_COPIED:
322  *    If we know we'll immediately be committing the
323  *    transaction (FSYNC or FDSYNC), the we allocate a larger
324  *    log record here for the data and copy the data in.
325  * WR_NEED_COPY:
326  *    Otherwise we don't allocate a buffer, and *if* we need to
327  *    flush the write later then a buffer is allocated and
328  *    we retrieve the data using the dmu.
329  */
330 typedef enum {
331 	WR_INDIRECT,	/* indirect - a large write (dmu_sync() data */
332 			/* and put blkptr in log, rather than actual data) */
333 	WR_COPIED,	/* immediate - data is copied into lr_write_t */
334 	WR_NEED_COPY,	/* immediate - data needs to be copied if pushed */
335 } itx_wr_state_t;
336 
337 typedef struct itx {
338 	list_node_t	itx_node;	/* linkage on zl_itx_list */
339 	void		*itx_private;	/* type-specific opaque data */
340 	itx_wr_state_t	itx_wr_state;	/* write state */
341 	uint8_t		itx_sync;	/* synchronous transaction */
342 	uint64_t	itx_sod;	/* record size on disk */
343 	lr_t		itx_lr;		/* common part of log record */
344 	/* followed by type-specific part of lr_xx_t and its immediate data */
345 } itx_t;
346 
347 
348 /*
349  * zgd_t is passed through dmu_sync() to the callback routine zfs_get_done()
350  * to handle the cleanup of the dmu_sync() buffer write
351  */
352 typedef struct {
353 	zilog_t		*zgd_zilog;	/* zilog */
354 	blkptr_t	*zgd_bp;	/* block pointer */
355 	struct rl	*zgd_rl;	/* range lock */
356 } zgd_t;
357 
358 
359 typedef void zil_parse_blk_func_t(zilog_t *zilog, blkptr_t *bp, void *arg,
360     uint64_t txg);
361 typedef void zil_parse_lr_func_t(zilog_t *zilog, lr_t *lr, void *arg,
362     uint64_t txg);
363 typedef int zil_replay_func_t();
364 typedef int zil_get_data_t(void *arg, lr_write_t *lr, char *dbuf, zio_t *zio);
365 
366 extern uint64_t	zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func,
367     zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg);
368 
369 extern void	zil_init(void);
370 extern void	zil_fini(void);
371 
372 extern zilog_t	*zil_alloc(objset_t *os, zil_header_t *zh_phys);
373 extern void	zil_free(zilog_t *zilog);
374 
375 extern zilog_t	*zil_open(objset_t *os, zil_get_data_t *get_data);
376 extern void	zil_close(zilog_t *zilog);
377 
378 extern void	zil_replay(objset_t *os, void *arg,
379     zil_replay_func_t *replay_func[TX_MAX_TYPE]);
380 extern void	zil_destroy(zilog_t *zilog, boolean_t keep_first);
381 extern void	zil_rollback_destroy(zilog_t *zilog, dmu_tx_t *tx);
382 
383 extern itx_t	*zil_itx_create(uint64_t txtype, size_t lrsize);
384 extern uint64_t zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx);
385 
386 extern void	zil_commit(zilog_t *zilog, uint64_t seq, uint64_t oid);
387 
388 extern int	zil_claim(char *osname, void *txarg);
389 extern int	zil_check_log_chain(char *osname, void *txarg);
390 extern int	zil_clear_log_chain(char *osname, void *txarg);
391 extern void	zil_sync(zilog_t *zilog, dmu_tx_t *tx);
392 extern void	zil_clean(zilog_t *zilog);
393 extern int	zil_is_committed(zilog_t *zilog);
394 
395 extern int	zil_suspend(zilog_t *zilog);
396 extern void	zil_resume(zilog_t *zilog);
397 
398 extern void	zil_add_block(zilog_t *zilog, blkptr_t *bp);
399 
400 extern int zil_disable;
401 
402 #ifdef	__cplusplus
403 }
404 #endif
405 
406 #endif	/* _SYS_ZIL_H */
407