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, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #ifndef _SYS_DNODE_H 28 #define _SYS_DNODE_H 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 #include <sys/zfs_context.h> 33 #include <sys/avl.h> 34 #include <sys/spa.h> 35 #include <sys/txg.h> 36 #include <sys/refcount.h> 37 #include <sys/dmu_zfetch.h> 38 39 #ifdef __cplusplus 40 extern "C" { 41 #endif 42 43 /* 44 * Flags. 45 */ 46 #define DNODE_MUST_BE_ALLOCATED 1 47 #define DNODE_MUST_BE_FREE 2 48 49 /* 50 * Fixed constants. 51 */ 52 #define DNODE_SHIFT 9 /* 512 bytes */ 53 #define DN_MIN_INDBLKSHIFT 10 /* 1k */ 54 #define DN_MAX_INDBLKSHIFT 14 /* 16k */ 55 #define DNODE_BLOCK_SHIFT 14 /* 16k */ 56 #define DNODE_CORE_SIZE 64 /* 64 bytes for dnode sans blkptrs */ 57 #define DN_MAX_OBJECT_SHIFT 48 /* 256 trillion (zfs_fid_t limit) */ 58 #define DN_MAX_OFFSET_SHIFT 64 /* 2^64 bytes in a dnode */ 59 60 /* 61 * Derived constants. 62 */ 63 #define DNODE_SIZE (1 << DNODE_SHIFT) 64 #define DN_MAX_NBLKPTR ((DNODE_SIZE - DNODE_CORE_SIZE) >> SPA_BLKPTRSHIFT) 65 #define DN_MAX_BONUSLEN (DNODE_SIZE - DNODE_CORE_SIZE - (1 << SPA_BLKPTRSHIFT)) 66 67 #define DNODES_PER_BLOCK_SHIFT (DNODE_BLOCK_SHIFT - DNODE_SHIFT) 68 #define DNODES_PER_BLOCK (1ULL << DNODES_PER_BLOCK_SHIFT) 69 #define DNODES_PER_LEVEL_SHIFT (DN_MAX_INDBLKSHIFT - SPA_BLKPTRSHIFT) 70 71 #define DN_META_DNODE_LEVELS \ 72 (1 + (DN_MAX_OBJECT_SHIFT - DNODE_SHIFT + SPA_BLKPTRSHIFT - \ 73 DNODES_PER_BLOCK_SHIFT) / DNODES_PER_LEVEL_SHIFT) 74 75 /* The +2 here is a cheesy way to round up */ 76 #define DN_MAX_LEVELS (2 + ((DN_MAX_OFFSET_SHIFT - SPA_MINBLOCKSHIFT) / \ 77 (DN_MIN_INDBLKSHIFT - SPA_BLKPTRSHIFT))) 78 79 #define DN_MAX_OBJECT \ 80 ((uint64_t)DN_MAX_NBLKPTR << (DNODES_PER_BLOCK_SHIFT + \ 81 (DN_META_DNODE_LEVELS - 1) * DNODES_PER_LEVEL_SHIFT)) 82 83 #define DN_BONUS(dnp) ((void*)((dnp)->dn_bonus + \ 84 (((dnp)->dn_nblkptr - 1) * sizeof (blkptr_t)))) 85 86 #define EPB(blkshift, typeshift) (1 << (blkshift - typeshift)) 87 88 struct dmu_buf_impl; 89 struct objset_impl; 90 struct zio; 91 92 enum dnode_dirtycontext { 93 DN_UNDIRTIED, 94 DN_DIRTY_OPEN, 95 DN_DIRTY_SYNC 96 }; 97 98 typedef struct dnode_phys { 99 uint8_t dn_type; /* dmu_object_type_t */ 100 uint8_t dn_indblkshift; /* ln2(indirect block size) */ 101 uint8_t dn_nlevels; /* 1=dn_blkptr->data blocks */ 102 uint8_t dn_nblkptr; /* length of dn_blkptr */ 103 uint8_t dn_bonustype; /* type of data in bonus buffer */ 104 uint8_t dn_checksum; /* ZIO_CHECKSUM type */ 105 uint8_t dn_compress; /* ZIO_COMPRESS type */ 106 uint8_t dn_pad1[1]; 107 uint16_t dn_datablkszsec; /* data block size in 512b sectors */ 108 uint16_t dn_bonuslen; /* length of dn_bonus */ 109 uint8_t dn_pad2[4]; 110 111 /* accounting is protected by dn_dirty_mtx */ 112 uint64_t dn_maxblkid; /* largest allocated block ID */ 113 uint64_t dn_secphys; /* 512b sectors of disk space used */ 114 115 uint64_t dn_pad3[4]; 116 117 blkptr_t dn_blkptr[1]; 118 uint8_t dn_bonus[DN_MAX_BONUSLEN]; 119 } dnode_phys_t; 120 121 typedef struct dnode { 122 /* 123 * lock ordering: 124 * 125 * db_mtx > dn_dirty_mtx 126 * dbuf_syncdone 127 * 128 * dn_struct_rwlock/r > dn_dirty_mtx 129 * dmu_object_info 130 * 131 * dn_struct_rwlock/r > db_mtx > dn_dirty_mtx 132 * dbuf_dirty 133 * dbuf_setdirty 134 * 135 * dn_struct_rwlock/w > db_mtx > dn_mtx 136 * dnode_increase_indirection -> dbuf_find 137 * dbuf_hold_impl 138 * dnode_set_bonus 139 * 140 * dn_struct_rwlock/w > dn_mtx 141 * dnode_increase_indirection 142 * 143 * dn_dirty_mtx > dn_mtx 144 * dnode_buf_pageout 145 * 146 * db_mtx > dn_mtx 147 * dbuf_create 148 */ 149 150 /* 151 * dn_struct_rwlock protects the structure of the dnode. 152 * In particular, it protects the number of levels of indirection. 153 */ 154 krwlock_t dn_struct_rwlock; 155 156 /* 157 * Our link on dataset's dd_dnodes list. 158 * Protected by dd_accounting_mtx. 159 */ 160 list_node_t dn_link; 161 162 /* immutable: */ 163 struct objset_impl *dn_objset; 164 uint64_t dn_object; 165 struct dmu_buf_impl *dn_dbuf; 166 dnode_phys_t *dn_phys; /* pointer into dn->dn_dbuf->db.db_data */ 167 168 /* 169 * Copies of stuff in dn_phys. They're valid here even before 170 * the dnode is first synced. 171 */ 172 dmu_object_type_t dn_type; /* object type (immutable) */ 173 uint8_t dn_bonustype; /* bonus type (immutable) */ 174 uint16_t dn_bonuslen; /* bonus length (immutable) */ 175 uint8_t dn_nblkptr; /* number of blkptrs (immutable) */ 176 uint8_t dn_datablkshift; /* zero if blksz not power of 2! */ 177 uint32_t dn_datablksz; /* in bytes */ 178 uint16_t dn_datablkszsec; /* in 512b sectors */ 179 180 uint8_t dn_checksum; /* ZIO_CHECKSUM type */ 181 uint8_t dn_compress; /* ZIO_COMPRESS type */ 182 183 /* 184 * The following are kept up-to-date in the *open* context, the syncing 185 * context should only pay attention to the dn_next_* values. 186 */ 187 uint8_t dn_nlevels; 188 uint8_t dn_indblkshift; 189 190 uint8_t dn_next_nlevels[TXG_SIZE]; 191 uint8_t dn_next_indblkshift[TXG_SIZE]; 192 193 /* protected by os_lock: */ 194 uint32_t dn_dirtyblksz[TXG_SIZE]; /* dirty block size in bytes */ 195 list_node_t dn_dirty_link[TXG_SIZE]; /* next on dataset's dirty */ 196 197 /* protected by dn_mtx: */ 198 kmutex_t dn_mtx; 199 list_t dn_dirty_dbufs[TXG_SIZE]; 200 uint64_t dn_maxblkid; 201 avl_tree_t dn_ranges[TXG_SIZE]; 202 uint64_t dn_allocated_txg; 203 uint64_t dn_free_txg; 204 uint64_t dn_assigned_txg; 205 struct dmu_tx *dn_assigned_tx; /* if only one tx cares */ 206 kcondvar_t dn_notxholds; 207 enum dnode_dirtycontext dn_dirtyctx; 208 uint8_t *dn_dirtyctx_firstset; /* dbg: contents meaningless */ 209 210 /* protected by own devices */ 211 refcount_t dn_tx_holds; 212 refcount_t dn_holds; 213 214 kmutex_t dn_dbufs_mtx; 215 list_t dn_dbufs; /* linked list of descendent dbuf_t's */ 216 kcondvar_t dn_evicted; /* a child dbuf has been evicted */ 217 218 /* 219 * Performance hack: whenever we have a hold on the bonus buffer of a 220 * ZAP object, we will also have a hold on db0. This will keep the 221 * meta-data for a micro-zap object cached as long as the znode for the 222 * object is in the znode cache. 223 */ 224 struct dmu_buf_impl *dn_db0; 225 226 /* holds prefetch structure */ 227 struct zfetch dn_zfetch; 228 } dnode_t; 229 230 typedef struct free_range { 231 avl_node_t fr_node; 232 uint64_t fr_blkid; 233 uint64_t fr_nblks; 234 } free_range_t; 235 236 dnode_t *dnode_special_open(struct objset_impl *dd, dnode_phys_t *dnp, 237 uint64_t object); 238 void dnode_special_close(dnode_t *dn); 239 240 dnode_t *dnode_hold(struct objset_impl *dd, uint64_t object, void *ref); 241 dnode_t *dnode_hold_impl(struct objset_impl *dd, uint64_t object, int flag, 242 void *ref); 243 void dnode_add_ref(dnode_t *dn, void *ref); 244 void dnode_rele(dnode_t *dn, void *ref); 245 void dnode_setdirty(dnode_t *dn, dmu_tx_t *tx); 246 int dnode_sync(dnode_t *dn, int level, struct zio *zio, dmu_tx_t *tx); 247 void dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 248 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 249 void dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 250 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 251 void dnode_free(dnode_t *dn, dmu_tx_t *tx); 252 void dnode_byteswap(dnode_phys_t *dnp); 253 void dnode_buf_byteswap(void *buf, size_t size); 254 void dnode_verify(dnode_t *dn); 255 int dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx); 256 uint64_t dnode_current_max_length(dnode_t *dn); 257 uint64_t dnode_max_nonzero_offset(dnode_t *dn); 258 void dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx); 259 void dnode_clear_range(dnode_t *dn, uint64_t blkid, 260 uint64_t nblks, dmu_tx_t *tx); 261 void dnode_diduse_space(dnode_t *dn, int64_t space); 262 void dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx); 263 void dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx); 264 uint64_t dnode_block_freed(dnode_t *dn, uint64_t blkid); 265 void dnode_init(void); 266 void dnode_fini(void); 267 int dnode_next_offset(dnode_t *dn, boolean_t hole, uint64_t *off, int minlvl, 268 uint64_t blkfill); 269 270 #ifdef ZFS_DEBUG 271 272 /* 273 * There should be a ## between the string literal and fmt, to make it 274 * clear that we're joining two strings together, but that piece of shit 275 * gcc doesn't support that preprocessor token. 276 */ 277 #define dprintf_dnode(dn, fmt, ...) do { \ 278 if (zfs_flags & ZFS_DEBUG_DPRINTF) { \ 279 char __db_buf[32]; \ 280 uint64_t __db_obj = (dn)->dn_object; \ 281 if (__db_obj == DMU_META_DNODE_OBJECT) \ 282 (void) strcpy(__db_buf, "mdn"); \ 283 else \ 284 (void) snprintf(__db_buf, sizeof (__db_buf), "%lld", \ 285 (u_longlong_t)__db_obj);\ 286 dprintf_ds((dn)->dn_objset->os_dsl_dataset, "obj=%s " fmt, \ 287 __db_buf, __VA_ARGS__); \ 288 } \ 289 _NOTE(CONSTCOND) } while (0) 290 291 #define DNODE_VERIFY(dn) dnode_verify(dn) 292 #define FREE_VERIFY(db, start, end, tx) free_verify(db, start, end, tx) 293 294 #else 295 296 #define dprintf_dnode(db, fmt, ...) 297 #define DNODE_VERIFY(dn) 298 #define FREE_VERIFY(db, start, end, tx) 299 300 #endif 301 302 #ifdef __cplusplus 303 } 304 #endif 305 306 #endif /* _SYS_DNODE_H */ 307