/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2012, 2017 by Delphix. All rights reserved. * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. */ #ifndef _SYS_DNODE_H #define _SYS_DNODE_H #include #include #include #include #include #include #include #include #include #ifdef __cplusplus extern "C" { #endif /* * dnode_hold() flags. */ #define DNODE_MUST_BE_ALLOCATED 1 #define DNODE_MUST_BE_FREE 2 /* * dnode_next_offset() flags. */ #define DNODE_FIND_HOLE 1 #define DNODE_FIND_BACKWARDS 2 #define DNODE_FIND_HAVELOCK 4 /* * Fixed constants. */ #define DNODE_SHIFT 9 /* 512 bytes */ #define DN_MIN_INDBLKSHIFT 12 /* 4k */ /* * If we ever increase this value beyond 20, we need to revisit all logic that * does x << level * ebps to handle overflow. With a 1M indirect block size, * 4 levels of indirect blocks would not be able to guarantee addressing an * entire object, so 5 levels will be used, but 5 * (20 - 7) = 65. */ #define DN_MAX_INDBLKSHIFT 17 /* 128k */ #define DNODE_BLOCK_SHIFT 14 /* 16k */ #define DNODE_CORE_SIZE 64 /* 64 bytes for dnode sans blkptrs */ #define DN_MAX_OBJECT_SHIFT 48 /* 256 trillion (zfs_fid_t limit) */ #define DN_MAX_OFFSET_SHIFT 64 /* 2^64 bytes in a dnode */ /* * dnode id flags * * Note: a file will never ever have its ids moved from bonus->spill */ #define DN_ID_CHKED_BONUS 0x1 #define DN_ID_CHKED_SPILL 0x2 #define DN_ID_OLD_EXIST 0x4 #define DN_ID_NEW_EXIST 0x8 /* * Derived constants. */ #define DNODE_MIN_SIZE (1 << DNODE_SHIFT) #define DNODE_MAX_SIZE (1 << DNODE_BLOCK_SHIFT) #define DNODE_BLOCK_SIZE (1 << DNODE_BLOCK_SHIFT) #define DNODE_MIN_SLOTS (DNODE_MIN_SIZE >> DNODE_SHIFT) #define DNODE_MAX_SLOTS (DNODE_MAX_SIZE >> DNODE_SHIFT) #define DN_BONUS_SIZE(dnsize) ((dnsize) - DNODE_CORE_SIZE - \ (1 << SPA_BLKPTRSHIFT)) #define DN_SLOTS_TO_BONUSLEN(slots) DN_BONUS_SIZE((slots) << DNODE_SHIFT) #define DN_OLD_MAX_BONUSLEN (DN_BONUS_SIZE(DNODE_MIN_SIZE)) #define DN_MAX_NBLKPTR ((DNODE_MIN_SIZE - DNODE_CORE_SIZE) >> SPA_BLKPTRSHIFT) #define DN_MAX_OBJECT (1ULL << DN_MAX_OBJECT_SHIFT) #define DN_ZERO_BONUSLEN (DN_BONUS_SIZE(DNODE_MAX_SIZE) + 1) #define DN_KILL_SPILLBLK (1) #define DN_SLOT_UNINIT ((void *)NULL) /* Uninitialized */ #define DN_SLOT_FREE ((void *)1UL) /* Free slot */ #define DN_SLOT_ALLOCATED ((void *)2UL) /* Allocated slot */ #define DN_SLOT_INTERIOR ((void *)3UL) /* Interior allocated slot */ #define DN_SLOT_IS_PTR(dn) ((void *)dn > DN_SLOT_INTERIOR) #define DN_SLOT_IS_VALID(dn) ((void *)dn != NULL) #define DNODES_PER_BLOCK_SHIFT (DNODE_BLOCK_SHIFT - DNODE_SHIFT) #define DNODES_PER_BLOCK (1ULL << DNODES_PER_BLOCK_SHIFT) /* * This is inaccurate if the indblkshift of the particular object is not the * max. But it's only used by userland to calculate the zvol reservation. */ #define DNODES_PER_LEVEL_SHIFT (DN_MAX_INDBLKSHIFT - SPA_BLKPTRSHIFT) #define DNODES_PER_LEVEL (1ULL << DNODES_PER_LEVEL_SHIFT) #define DN_MAX_LEVELS (DIV_ROUND_UP(DN_MAX_OFFSET_SHIFT - SPA_MINBLOCKSHIFT, \ DN_MIN_INDBLKSHIFT - SPA_BLKPTRSHIFT) + 1) #define DN_BONUS(dnp) ((void*)((dnp)->dn_bonus + \ (((dnp)->dn_nblkptr - 1) * sizeof (blkptr_t)))) #define DN_MAX_BONUS_LEN(dnp) \ ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) ? \ (uint8_t *)DN_SPILL_BLKPTR(dnp) - (uint8_t *)DN_BONUS(dnp) : \ (uint8_t *)(dnp + (dnp->dn_extra_slots + 1)) - (uint8_t *)DN_BONUS(dnp)) #define DN_USED_BYTES(dnp) (((dnp)->dn_flags & DNODE_FLAG_USED_BYTES) ? \ (dnp)->dn_used : (dnp)->dn_used << SPA_MINBLOCKSHIFT) #define EPB(blkshift, typeshift) (1 << (blkshift - typeshift)) struct dmu_buf_impl; struct objset; struct zio; enum dnode_dirtycontext { DN_UNDIRTIED, DN_DIRTY_OPEN, DN_DIRTY_SYNC }; /* Is dn_used in bytes? if not, it's in multiples of SPA_MINBLOCKSIZE */ #define DNODE_FLAG_USED_BYTES (1 << 0) #define DNODE_FLAG_USERUSED_ACCOUNTED (1 << 1) /* Does dnode have a SA spill blkptr in bonus? */ #define DNODE_FLAG_SPILL_BLKPTR (1 << 2) /* User/Group dnode accounting */ #define DNODE_FLAG_USEROBJUSED_ACCOUNTED (1 << 3) #define DNODE_CRYPT_PORTABLE_FLAGS_MASK (DNODE_FLAG_SPILL_BLKPTR) /* * VARIABLE-LENGTH (LARGE) DNODES * * The motivation for variable-length dnodes is to eliminate the overhead * associated with using spill blocks. Spill blocks are used to store * system attribute data (i.e. file metadata) that does not fit in the * dnode's bonus buffer. By allowing a larger bonus buffer area the use of * a spill block can be avoided. Spill blocks potentially incur an * additional read I/O for every dnode in a dnode block. As a worst case * example, reading 32 dnodes from a 16k dnode block and all of the spill * blocks could issue 33 separate reads. Now suppose those dnodes have size * 1024 and therefore don't need spill blocks. Then the worst case number * of blocks read is reduced to from 33 to two--one per dnode block. * * ZFS-on-Linux systems that make heavy use of extended attributes benefit * from this feature. In particular, ZFS-on-Linux supports the xattr=sa * dataset property which allows file extended attribute data to be stored * in the dnode bonus buffer as an alternative to the traditional * directory-based format. Workloads such as SELinux and the Lustre * distributed filesystem often store enough xattr data to force spill * blocks when xattr=sa is in effect. Large dnodes may therefore provide a * performance benefit to such systems. Other use cases that benefit from * this feature include files with large ACLs and symbolic links with long * target names. * * The size of a dnode may be a multiple of 512 bytes up to the size of a * dnode block (currently 16384 bytes). The dn_extra_slots field of the * on-disk dnode_phys_t structure describes the size of the physical dnode * on disk. The field represents how many "extra" dnode_phys_t slots a * dnode consumes in its dnode block. This convention results in a value of * 0 for 512 byte dnodes which preserves on-disk format compatibility with * older software which doesn't support large dnodes. * * Similarly, the in-memory dnode_t structure has a dn_num_slots field * to represent the total number of dnode_phys_t slots consumed on disk. * Thus dn->dn_num_slots is 1 greater than the corresponding * dnp->dn_extra_slots. This difference in convention was adopted * because, unlike on-disk structures, backward compatibility is not a * concern for in-memory objects, so we used a more natural way to * represent size for a dnode_t. * * The default size for newly created dnodes is determined by the value of * the "dnodesize" dataset property. By default the property is set to * "legacy" which is compatible with older software. Setting the property * to "auto" will allow the filesystem to choose the most suitable dnode * size. Currently this just sets the default dnode size to 1k, but future * code improvements could dynamically choose a size based on observed * workload patterns. Dnodes of varying sizes can coexist within the same * dataset and even within the same dnode block. */ typedef struct dnode_phys { uint8_t dn_type; /* dmu_object_type_t */ uint8_t dn_indblkshift; /* ln2(indirect block size) */ uint8_t dn_nlevels; /* 1=dn_blkptr->data blocks */ uint8_t dn_nblkptr; /* length of dn_blkptr */ uint8_t dn_bonustype; /* type of data in bonus buffer */ uint8_t dn_checksum; /* ZIO_CHECKSUM type */ uint8_t dn_compress; /* ZIO_COMPRESS type */ uint8_t dn_flags; /* DNODE_FLAG_* */ uint16_t dn_datablkszsec; /* data block size in 512b sectors */ uint16_t dn_bonuslen; /* length of dn_bonus */ uint8_t dn_extra_slots; /* # of subsequent slots consumed */ uint8_t dn_pad2[3]; /* accounting is protected by dn_dirty_mtx */ uint64_t dn_maxblkid; /* largest allocated block ID */ uint64_t dn_used; /* bytes (or sectors) of disk space */ uint64_t dn_pad3[4]; /* * The tail region is 448 bytes for a 512 byte dnode, and * correspondingly larger for larger dnode sizes. The spill * block pointer, when present, is always at the end of the tail * region. There are three ways this space may be used, using * a 512 byte dnode for this diagram: * * 0 64 128 192 256 320 384 448 (offset) * +---------------+---------------+---------------+-------+ * | dn_blkptr[0] | dn_blkptr[1] | dn_blkptr[2] | / | * +---------------+---------------+---------------+-------+ * | dn_blkptr[0] | dn_bonus[0..319] | * +---------------+-----------------------+---------------+ * | dn_blkptr[0] | dn_bonus[0..191] | dn_spill | * +---------------+-----------------------+---------------+ */ union { blkptr_t dn_blkptr[1+DN_OLD_MAX_BONUSLEN/sizeof (blkptr_t)]; struct { blkptr_t __dn_ignore1; uint8_t dn_bonus[DN_OLD_MAX_BONUSLEN]; }; struct { blkptr_t __dn_ignore2; uint8_t __dn_ignore3[DN_OLD_MAX_BONUSLEN - sizeof (blkptr_t)]; blkptr_t dn_spill; }; }; } dnode_phys_t; #define DN_SPILL_BLKPTR(dnp) (blkptr_t *)((char *)(dnp) + \ (((dnp)->dn_extra_slots + 1) << DNODE_SHIFT) - (1 << SPA_BLKPTRSHIFT)) struct dnode { /* * Protects the structure of the dnode, including the number of levels * of indirection (dn_nlevels), dn_maxblkid, and dn_next_* */ krwlock_t dn_struct_rwlock; /* Our link on dn_objset->os_dnodes list; protected by os_lock. */ list_node_t dn_link; /* immutable: */ struct objset *dn_objset; uint64_t dn_object; struct dmu_buf_impl *dn_dbuf; struct dnode_handle *dn_handle; dnode_phys_t *dn_phys; /* pointer into dn->dn_dbuf->db.db_data */ /* * Copies of stuff in dn_phys. They're valid in the open * context (eg. even before the dnode is first synced). * Where necessary, these are protected by dn_struct_rwlock. */ dmu_object_type_t dn_type; /* object type */ uint16_t dn_bonuslen; /* bonus length */ uint8_t dn_bonustype; /* bonus type */ uint8_t dn_nblkptr; /* number of blkptrs (immutable) */ uint8_t dn_checksum; /* ZIO_CHECKSUM type */ uint8_t dn_compress; /* ZIO_COMPRESS type */ uint8_t dn_nlevels; uint8_t dn_indblkshift; uint8_t dn_datablkshift; /* zero if blksz not power of 2! */ uint8_t dn_moved; /* Has this dnode been moved? */ uint16_t dn_datablkszsec; /* in 512b sectors */ uint32_t dn_datablksz; /* in bytes */ uint64_t dn_maxblkid; uint8_t dn_next_type[TXG_SIZE]; uint8_t dn_num_slots; /* metadnode slots consumed on disk */ uint8_t dn_next_nblkptr[TXG_SIZE]; uint8_t dn_next_nlevels[TXG_SIZE]; uint8_t dn_next_indblkshift[TXG_SIZE]; uint8_t dn_next_bonustype[TXG_SIZE]; uint8_t dn_rm_spillblk[TXG_SIZE]; /* for removing spill blk */ uint16_t dn_next_bonuslen[TXG_SIZE]; uint32_t dn_next_blksz[TXG_SIZE]; /* next block size in bytes */ /* protected by dn_dbufs_mtx; declared here to fill 32-bit hole */ uint32_t dn_dbufs_count; /* count of dn_dbufs */ /* protected by os_lock: */ multilist_node_t dn_dirty_link[TXG_SIZE]; /* next on dataset's dirty */ /* protected by dn_mtx: */ kmutex_t dn_mtx; list_t dn_dirty_records[TXG_SIZE]; struct range_tree *dn_free_ranges[TXG_SIZE]; uint64_t dn_allocated_txg; uint64_t dn_free_txg; uint64_t dn_assigned_txg; kcondvar_t dn_notxholds; enum dnode_dirtycontext dn_dirtyctx; uint8_t *dn_dirtyctx_firstset; /* dbg: contents meaningless */ /* protected by own devices */ refcount_t dn_tx_holds; refcount_t dn_holds; kmutex_t dn_dbufs_mtx; /* * Descendent dbufs, ordered by dbuf_compare. Note that dn_dbufs * can contain multiple dbufs of the same (level, blkid) when a * dbuf is marked DB_EVICTING without being removed from * dn_dbufs. To maintain the avl invariant that there cannot be * duplicate entries, we order the dbufs by an arbitrary value - * their address in memory. This means that dn_dbufs cannot be used to * directly look up a dbuf. Instead, callers must use avl_walk, have * a reference to the dbuf, or look up a non-existent node with * db_state = DB_SEARCH (see dbuf_free_range for an example). */ avl_tree_t dn_dbufs; /* protected by dn_struct_rwlock */ struct dmu_buf_impl *dn_bonus; /* bonus buffer dbuf */ boolean_t dn_have_spill; /* have spill or are spilling */ /* parent IO for current sync write */ zio_t *dn_zio; /* used in syncing context */ uint64_t dn_oldused; /* old phys used bytes */ uint64_t dn_oldflags; /* old phys dn_flags */ uint64_t dn_olduid, dn_oldgid; uint64_t dn_newuid, dn_newgid; int dn_id_flags; /* holds prefetch structure */ struct zfetch dn_zfetch; }; /* * Adds a level of indirection between the dbuf and the dnode to avoid * iterating descendent dbufs in dnode_move(). Handles are not allocated * individually, but as an array of child dnodes in dnode_hold_impl(). */ typedef struct dnode_handle { /* Protects dnh_dnode from modification by dnode_move(). */ zrlock_t dnh_zrlock; dnode_t *dnh_dnode; } dnode_handle_t; typedef struct dnode_children { dmu_buf_user_t dnc_dbu; /* User evict data */ size_t dnc_count; /* number of children */ dnode_handle_t dnc_children[]; /* sized dynamically */ } dnode_children_t; typedef struct free_range { avl_node_t fr_node; uint64_t fr_blkid; uint64_t fr_nblks; } free_range_t; void dnode_special_open(struct objset *dd, dnode_phys_t *dnp, uint64_t object, dnode_handle_t *dnh); void dnode_special_close(dnode_handle_t *dnh); void dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx); void dnode_setbonus_type(dnode_t *dn, dmu_object_type_t, dmu_tx_t *tx); void dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx); int dnode_hold(struct objset *dd, uint64_t object, void *ref, dnode_t **dnp); int dnode_hold_impl(struct objset *dd, uint64_t object, int flag, int dn_slots, void *ref, dnode_t **dnp); boolean_t dnode_add_ref(dnode_t *dn, void *ref); void dnode_rele(dnode_t *dn, void *ref); void dnode_rele_and_unlock(dnode_t *dn, void *tag); void dnode_setdirty(dnode_t *dn, dmu_tx_t *tx); void dnode_sync(dnode_t *dn, dmu_tx_t *tx); void dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, dmu_object_type_t bonustype, int bonuslen, int dn_slots, dmu_tx_t *tx); void dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, dmu_object_type_t bonustype, int bonuslen, int dn_slots, dmu_tx_t *tx); void dnode_free(dnode_t *dn, dmu_tx_t *tx); void dnode_byteswap(dnode_phys_t *dnp); void dnode_buf_byteswap(void *buf, size_t size); void dnode_verify(dnode_t *dn); int dnode_set_nlevels(dnode_t *dn, int nlevels, dmu_tx_t *tx); int dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx); void dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx); void dnode_diduse_space(dnode_t *dn, int64_t space); void dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t); uint64_t dnode_block_freed(dnode_t *dn, uint64_t blkid); void dnode_init(void); void dnode_fini(void); int dnode_next_offset(dnode_t *dn, int flags, uint64_t *off, int minlvl, uint64_t blkfill, uint64_t txg); void dnode_evict_dbufs(dnode_t *dn); void dnode_evict_bonus(dnode_t *dn); #define DNODE_IS_CACHEABLE(_dn) \ ((_dn)->dn_objset->os_primary_cache == ZFS_CACHE_ALL || \ (DMU_OT_IS_METADATA((_dn)->dn_type) && \ (_dn)->dn_objset->os_primary_cache == ZFS_CACHE_METADATA)) #define DNODE_META_IS_CACHEABLE(_dn) \ ((_dn)->dn_objset->os_primary_cache == ZFS_CACHE_ALL || \ (_dn)->dn_objset->os_primary_cache == ZFS_CACHE_METADATA) /* * Used for dnodestats kstat. */ typedef struct dnode_stats { /* * Number of failed attempts to hold a meta dnode dbuf. */ kstat_named_t dnode_hold_dbuf_hold; /* * Number of failed attempts to read a meta dnode dbuf. */ kstat_named_t dnode_hold_dbuf_read; /* * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) was able * to hold the requested object number which was allocated. This is * the common case when looking up any allocated object number. */ kstat_named_t dnode_hold_alloc_hits; /* * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) was not * able to hold the request object number because it was not allocated. */ kstat_named_t dnode_hold_alloc_misses; /* * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) was not * able to hold the request object number because the object number * refers to an interior large dnode slot. */ kstat_named_t dnode_hold_alloc_interior; /* * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) needed * to retry acquiring slot zrl locks due to contention. */ kstat_named_t dnode_hold_alloc_lock_retry; /* * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) did not * need to create the dnode because another thread did so after * dropping the read lock but before acquiring the write lock. */ kstat_named_t dnode_hold_alloc_lock_misses; /* * Number of times dnode_hold(..., DNODE_MUST_BE_ALLOCATED) found * a free dnode instantiated by dnode_create() but not yet allocated * by dnode_allocate(). */ kstat_named_t dnode_hold_alloc_type_none; /* * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) was able * to hold the requested range of free dnode slots. */ kstat_named_t dnode_hold_free_hits; /* * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) was not * able to hold the requested range of free dnode slots because * at least one slot was allocated. */ kstat_named_t dnode_hold_free_misses; /* * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) was not * able to hold the requested range of free dnode slots because * after acquiring the zrl lock at least one slot was allocated. */ kstat_named_t dnode_hold_free_lock_misses; /* * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) needed * to retry acquiring slot zrl locks due to contention. */ kstat_named_t dnode_hold_free_lock_retry; /* * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) requested * a range of dnode slots which were held by another thread. */ kstat_named_t dnode_hold_free_refcount; /* * Number of times dnode_hold(..., DNODE_MUST_BE_FREE) requested * a range of dnode slots which would overflow the dnode_phys_t. */ kstat_named_t dnode_hold_free_overflow; /* * Number of times a dnode_hold(...) was attempted on a dnode * which had already been unlinked in an earlier txg. */ kstat_named_t dnode_hold_free_txg; /* * Number of new dnodes allocated by dnode_allocate(). */ kstat_named_t dnode_allocate; /* * Number of dnodes re-allocated by dnode_reallocate(). */ kstat_named_t dnode_reallocate; /* * Number of meta dnode dbufs evicted. */ kstat_named_t dnode_buf_evict; /* * Number of times dmu_object_alloc*() reached the end of the existing * object ID chunk and advanced to a new one. */ kstat_named_t dnode_alloc_next_chunk; /* * Number of times multiple threads attempted to allocate a dnode * from the same block of free dnodes. */ kstat_named_t dnode_alloc_race; /* * Number of times dmu_object_alloc*() was forced to advance to the * next meta dnode dbuf due to an error from dmu_object_next(). */ kstat_named_t dnode_alloc_next_block; /* * Statistics for tracking dnodes which have been moved. */ kstat_named_t dnode_move_invalid; kstat_named_t dnode_move_recheck1; kstat_named_t dnode_move_recheck2; kstat_named_t dnode_move_special; kstat_named_t dnode_move_handle; kstat_named_t dnode_move_rwlock; kstat_named_t dnode_move_active; } dnode_stats_t; extern dnode_stats_t dnode_stats; #define DNODE_STAT_INCR(stat, val) \ atomic_add_64(&dnode_stats.stat.value.ui64, (val)); #define DNODE_STAT_BUMP(stat) \ DNODE_STAT_INCR(stat, 1); #ifdef ZFS_DEBUG /* * There should be a ## between the string literal and fmt, to make it * clear that we're joining two strings together, but that piece of shit * gcc doesn't support that preprocessor token. */ #define dprintf_dnode(dn, fmt, ...) do { \ if (zfs_flags & ZFS_DEBUG_DPRINTF) { \ char __db_buf[32]; \ uint64_t __db_obj = (dn)->dn_object; \ if (__db_obj == DMU_META_DNODE_OBJECT) \ (void) strcpy(__db_buf, "mdn"); \ else \ (void) snprintf(__db_buf, sizeof (__db_buf), "%lld", \ (u_longlong_t)__db_obj);\ dprintf_ds((dn)->dn_objset->os_dsl_dataset, "obj=%s " fmt, \ __db_buf, __VA_ARGS__); \ } \ _NOTE(CONSTCOND) } while (0) #define DNODE_VERIFY(dn) dnode_verify(dn) #define FREE_VERIFY(db, start, end, tx) free_verify(db, start, end, tx) #else #define dprintf_dnode(db, fmt, ...) #define DNODE_VERIFY(dn) #define FREE_VERIFY(db, start, end, tx) #endif #ifdef __cplusplus } #endif #endif /* _SYS_DNODE_H */