xref: /titanic_50/usr/src/uts/common/fs/zfs/sys/zil.h (revision 975c32a05c38c6fa808592dd35fa6dba183ca077)
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_WRITE2		20	/* dmu_sync EALREADY write */
143 #define	TX_MAX_TYPE		21	/* Max transaction type */
144 
145 /*
146  * The transactions for mkdir, symlink, remove, rmdir, link, and rename
147  * may have the following bit set, indicating the original request
148  * specified case-insensitive handling of names.
149  */
150 #define	TX_CI	((uint64_t)0x1 << 63) /* case-insensitive behavior requested */
151 
152 /*
153  * Format of log records.
154  * The fields are carefully defined to allow them to be aligned
155  * and sized the same on sparc & intel architectures.
156  * Each log record has a common structure at the beginning.
157  *
158  * Note, lrc_seq holds two different sequence numbers. Whilst in memory
159  * it contains the transaction sequence number.  The log record on
160  * disk holds the sequence number of all log records which is used to
161  * ensure we don't replay the same record.  The two sequence numbers are
162  * different because the transactions can now be pushed out of order.
163  */
164 typedef struct {			/* common log record header */
165 	uint64_t	lrc_txtype;	/* intent log transaction type */
166 	uint64_t	lrc_reclen;	/* transaction record length */
167 	uint64_t	lrc_txg;	/* dmu transaction group number */
168 	uint64_t	lrc_seq;	/* see comment above */
169 } lr_t;
170 
171 /*
172  * Handle option extended vattr attributes.
173  *
174  * Whenever new attributes are added the version number
175  * will need to be updated as will code in
176  * zfs_log.c and zfs_replay.c
177  */
178 typedef struct {
179 	uint32_t	lr_attr_masksize; /* number of elements in array */
180 	uint32_t	lr_attr_bitmap; /* First entry of array */
181 	/* remainder of array and any additional fields */
182 } lr_attr_t;
183 
184 /*
185  * log record for creates without optional ACL.
186  * This log record does support optional xvattr_t attributes.
187  */
188 typedef struct {
189 	lr_t		lr_common;	/* common portion of log record */
190 	uint64_t	lr_doid;	/* object id of directory */
191 	uint64_t	lr_foid;	/* object id of created file object */
192 	uint64_t	lr_mode;	/* mode of object */
193 	uint64_t	lr_uid;		/* uid of object */
194 	uint64_t	lr_gid;		/* gid of object */
195 	uint64_t	lr_gen;		/* generation (txg of creation) */
196 	uint64_t	lr_crtime[2];	/* creation time */
197 	uint64_t	lr_rdev;	/* rdev of object to create */
198 	/* name of object to create follows this */
199 	/* for symlinks, link content follows name */
200 	/* for creates with xvattr data, the name follows the xvattr info */
201 } lr_create_t;
202 
203 /*
204  * FUID ACL record will be an array of ACEs from the original ACL.
205  * If this array includes ephemeral IDs, the record will also include
206  * an array of log-specific FUIDs to replace the ephemeral IDs.
207  * Only one copy of each unique domain will be present, so the log-specific
208  * FUIDs will use an index into a compressed domain table.  On replay this
209  * information will be used to construct real FUIDs (and bypass idmap,
210  * since it may not be available).
211  */
212 
213 /*
214  * Log record for creates with optional ACL
215  * This log record is also used for recording any FUID
216  * information needed for replaying the create.  If the
217  * file doesn't have any actual ACEs then the lr_aclcnt
218  * would be zero.
219  */
220 typedef struct {
221 	lr_create_t	lr_create;	/* common create portion */
222 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
223 	uint64_t	lr_domcnt;	/* number of unique domains */
224 	uint64_t	lr_fuidcnt;	/* number of real fuids */
225 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
226 	uint64_t	lr_acl_flags;	/* ACL flags */
227 	/* lr_acl_bytes number of variable sized ace's follows */
228 	/* if create is also setting xvattr's, then acl data follows xvattr */
229 	/* if ACE FUIDs are needed then they will follow the xvattr_t */
230 	/* Following the FUIDs will be the domain table information. */
231 	/* The FUIDs for the owner and group will be in the lr_create */
232 	/* portion of the record. */
233 	/* name follows ACL data */
234 } lr_acl_create_t;
235 
236 typedef struct {
237 	lr_t		lr_common;	/* common portion of log record */
238 	uint64_t	lr_doid;	/* obj id of directory */
239 	/* name of object to remove follows this */
240 } lr_remove_t;
241 
242 typedef struct {
243 	lr_t		lr_common;	/* common portion of log record */
244 	uint64_t	lr_doid;	/* obj id of directory */
245 	uint64_t	lr_link_obj;	/* obj id of link */
246 	/* name of object to link follows this */
247 } lr_link_t;
248 
249 typedef struct {
250 	lr_t		lr_common;	/* common portion of log record */
251 	uint64_t	lr_sdoid;	/* obj id of source directory */
252 	uint64_t	lr_tdoid;	/* obj id of target directory */
253 	/* 2 strings: names of source and destination follow this */
254 } lr_rename_t;
255 
256 typedef struct {
257 	lr_t		lr_common;	/* common portion of log record */
258 	uint64_t	lr_foid;	/* file object to write */
259 	uint64_t	lr_offset;	/* offset to write to */
260 	uint64_t	lr_length;	/* user data length to write */
261 	uint64_t	lr_blkoff;	/* offset represented by lr_blkptr */
262 	blkptr_t	lr_blkptr;	/* spa block pointer for replay */
263 	/* write data will follow for small writes */
264 } lr_write_t;
265 
266 typedef struct {
267 	lr_t		lr_common;	/* common portion of log record */
268 	uint64_t	lr_foid;	/* object id of file to truncate */
269 	uint64_t	lr_offset;	/* offset to truncate from */
270 	uint64_t	lr_length;	/* length to truncate */
271 } lr_truncate_t;
272 
273 typedef struct {
274 	lr_t		lr_common;	/* common portion of log record */
275 	uint64_t	lr_foid;	/* file object to change attributes */
276 	uint64_t	lr_mask;	/* mask of attributes to set */
277 	uint64_t	lr_mode;	/* mode to set */
278 	uint64_t	lr_uid;		/* uid to set */
279 	uint64_t	lr_gid;		/* gid to set */
280 	uint64_t	lr_size;	/* size to set */
281 	uint64_t	lr_atime[2];	/* access time */
282 	uint64_t	lr_mtime[2];	/* modification time */
283 	/* optional attribute lr_attr_t may be here */
284 } lr_setattr_t;
285 
286 typedef struct {
287 	lr_t		lr_common;	/* common portion of log record */
288 	uint64_t	lr_foid;	/* obj id of file */
289 	uint64_t	lr_aclcnt;	/* number of acl entries */
290 	/* lr_aclcnt number of ace_t entries follow this */
291 } lr_acl_v0_t;
292 
293 typedef struct {
294 	lr_t		lr_common;	/* common portion of log record */
295 	uint64_t	lr_foid;	/* obj id of file */
296 	uint64_t	lr_aclcnt;	/* number of ACEs in ACL */
297 	uint64_t	lr_domcnt;	/* number of unique domains */
298 	uint64_t	lr_fuidcnt;	/* number of real fuids */
299 	uint64_t	lr_acl_bytes;	/* number of bytes in ACL */
300 	uint64_t	lr_acl_flags;	/* ACL flags */
301 	/* lr_acl_bytes number of variable sized ace's follows */
302 } lr_acl_t;
303 
304 /*
305  * ZIL structure definitions, interface function prototype and globals.
306  */
307 
308 /*
309  * Writes are handled in three different ways:
310  *
311  * WR_INDIRECT:
312  *    In this mode, if we need to commit the write later, then the block
313  *    is immediately written into the file system (using dmu_sync),
314  *    and a pointer to the block is put into the log record.
315  *    When the txg commits the block is linked in.
316  *    This saves additionally writing the data into the log record.
317  *    There are a few requirements for this to occur:
318  *	- write is greater than zfs/zvol_immediate_write_sz
319  *	- not using slogs (as slogs are assumed to always be faster
320  *	  than writing into the main pool)
321  *	- the write occupies only one block
322  * WR_COPIED:
323  *    If we know we'll immediately be committing the
324  *    transaction (FSYNC or FDSYNC), the we allocate a larger
325  *    log record here for the data and copy the data in.
326  * WR_NEED_COPY:
327  *    Otherwise we don't allocate a buffer, and *if* we need to
328  *    flush the write later then a buffer is allocated and
329  *    we retrieve the data using the dmu.
330  */
331 typedef enum {
332 	WR_INDIRECT,	/* indirect - a large write (dmu_sync() data */
333 			/* and put blkptr in log, rather than actual data) */
334 	WR_COPIED,	/* immediate - data is copied into lr_write_t */
335 	WR_NEED_COPY,	/* immediate - data needs to be copied if pushed */
336 } itx_wr_state_t;
337 
338 typedef struct itx {
339 	list_node_t	itx_node;	/* linkage on zl_itx_list */
340 	void		*itx_private;	/* type-specific opaque data */
341 	itx_wr_state_t	itx_wr_state;	/* write state */
342 	uint8_t		itx_sync;	/* synchronous transaction */
343 	uint64_t	itx_sod;	/* record size on disk */
344 	lr_t		itx_lr;		/* common part of log record */
345 	/* followed by type-specific part of lr_xx_t and its immediate data */
346 } itx_t;
347 
348 
349 /*
350  * zgd_t is passed through dmu_sync() to the callback routine zfs_get_done()
351  * to handle the cleanup of the dmu_sync() buffer write
352  */
353 typedef struct {
354 	zilog_t		*zgd_zilog;	/* zilog */
355 	blkptr_t	*zgd_bp;	/* block pointer */
356 	struct rl	*zgd_rl;	/* range lock */
357 } zgd_t;
358 
359 
360 typedef void zil_parse_blk_func_t(zilog_t *zilog, blkptr_t *bp, void *arg,
361     uint64_t txg);
362 typedef void zil_parse_lr_func_t(zilog_t *zilog, lr_t *lr, void *arg,
363     uint64_t txg);
364 typedef int zil_replay_func_t();
365 typedef int zil_get_data_t(void *arg, lr_write_t *lr, char *dbuf, zio_t *zio);
366 
367 extern uint64_t	zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func,
368     zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg);
369 
370 extern void	zil_init(void);
371 extern void	zil_fini(void);
372 
373 extern zilog_t	*zil_alloc(objset_t *os, zil_header_t *zh_phys);
374 extern void	zil_free(zilog_t *zilog);
375 
376 extern zilog_t	*zil_open(objset_t *os, zil_get_data_t *get_data);
377 extern void	zil_close(zilog_t *zilog);
378 
379 extern void	zil_replay(objset_t *os, void *arg,
380     zil_replay_func_t *replay_func[TX_MAX_TYPE]);
381 extern void	zil_destroy(zilog_t *zilog, boolean_t keep_first);
382 extern void	zil_rollback_destroy(zilog_t *zilog, dmu_tx_t *tx);
383 
384 extern itx_t	*zil_itx_create(uint64_t txtype, size_t lrsize);
385 extern uint64_t zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx);
386 
387 extern void	zil_commit(zilog_t *zilog, uint64_t seq, uint64_t oid);
388 
389 extern int	zil_vdev_offline(char *osname, void *txarg);
390 extern int	zil_claim(char *osname, void *txarg);
391 extern int	zil_check_log_chain(char *osname, void *txarg);
392 extern void	zil_sync(zilog_t *zilog, dmu_tx_t *tx);
393 extern void	zil_clean(zilog_t *zilog);
394 extern int	zil_is_committed(zilog_t *zilog);
395 
396 extern int	zil_suspend(zilog_t *zilog);
397 extern void	zil_resume(zilog_t *zilog);
398 
399 extern void	zil_add_block(zilog_t *zilog, blkptr_t *bp);
400 extern void	zil_set_logbias(zilog_t *zilog, uint64_t slogval);
401 extern void	zil_get_replay_data(zilog_t *zilog, lr_write_t *lr);
402 
403 extern int zil_disable;
404 
405 #ifdef	__cplusplus
406 }
407 #endif
408 
409 #endif	/* _SYS_ZIL_H */
410