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