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, 2016 by Delphix. All rights reserved.
24  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
25  */
26 
27 #ifndef   _SYS_DNODE_H
28 #define   _SYS_DNODE_H
29 
30 #include <sys/zfs_context.h>
31 #include <sys/avl.h>
32 #include <sys/spa.h>
33 #include <sys/txg.h>
34 #include <sys/zio.h>
35 #include <sys/refcount.h>
36 #include <sys/dmu_zfetch.h>
37 #include <sys/zrlock.h>
38 
39 #ifdef    __cplusplus
40 extern "C" {
41 #endif
42 
43 /*
44  * dnode_hold() flags.
45  */
46 #define   DNODE_MUST_BE_ALLOCATED       1
47 #define   DNODE_MUST_BE_FREE  2
48 
49 /*
50  * dnode_next_offset() flags.
51  */
52 #define   DNODE_FIND_HOLE               1
53 #define   DNODE_FIND_BACKWARDS          2
54 #define   DNODE_FIND_HAVELOCK 4
55 
56 /*
57  * Fixed constants.
58  */
59 #define   DNODE_SHIFT                   9         /* 512 bytes */
60 #define   DN_MIN_INDBLKSHIFT  12        /* 4k */
61 #define   DN_MAX_INDBLKSHIFT  17        /* 128k */
62 #define   DNODE_BLOCK_SHIFT   14        /* 16k */
63 #define   DNODE_CORE_SIZE               64        /* 64 bytes for dnode sans blkptrs */
64 #define   DN_MAX_OBJECT_SHIFT 48        /* 256 trillion (zfs_fid_t limit) */
65 #define   DN_MAX_OFFSET_SHIFT 64        /* 2^64 bytes in a dnode */
66 
67 /*
68  * dnode id flags
69  *
70  * Note: a file will never ever have its
71  * ids moved from bonus->spill
72  * and only in a crypto environment would it be on spill
73  */
74 #define   DN_ID_CHKED_BONUS   0x1
75 #define   DN_ID_CHKED_SPILL   0x2
76 #define   DN_ID_OLD_EXIST               0x4
77 #define   DN_ID_NEW_EXIST               0x8
78 
79 /*
80  * Derived constants.
81  */
82 #define   DNODE_SIZE          (1 << DNODE_SHIFT)
83 #define   DN_MAX_NBLKPTR      ((DNODE_SIZE - DNODE_CORE_SIZE) >> SPA_BLKPTRSHIFT)
84 #define   DN_MAX_BONUSLEN     (DNODE_SIZE - DNODE_CORE_SIZE - (1 << SPA_BLKPTRSHIFT))
85 #define   DN_MAX_OBJECT       (1ULL << DN_MAX_OBJECT_SHIFT)
86 #define   DN_ZERO_BONUSLEN    (DN_MAX_BONUSLEN + 1)
87 #define   DN_KILL_SPILLBLK (1)
88 
89 #define   DNODES_PER_BLOCK_SHIFT        (DNODE_BLOCK_SHIFT - DNODE_SHIFT)
90 #define   DNODES_PER_BLOCK    (1ULL << DNODES_PER_BLOCK_SHIFT)
91 
92 /*
93  * This is inaccurate if the indblkshift of the particular object is not the
94  * max.  But it's only used by userland to calculate the zvol reservation.
95  */
96 #define   DNODES_PER_LEVEL_SHIFT        (DN_MAX_INDBLKSHIFT - SPA_BLKPTRSHIFT)
97 #define   DNODES_PER_LEVEL    (1ULL << DNODES_PER_LEVEL_SHIFT)
98 
99 /* The +2 here is a cheesy way to round up */
100 #define   DN_MAX_LEVELS       (2 + ((DN_MAX_OFFSET_SHIFT - SPA_MINBLOCKSHIFT) / \
101           (DN_MIN_INDBLKSHIFT - SPA_BLKPTRSHIFT)))
102 
103 #define   DN_BONUS(dnp)       ((void*)((dnp)->dn_bonus + \
104           (((dnp)->dn_nblkptr - 1) * sizeof (blkptr_t))))
105 
106 #define   DN_USED_BYTES(dnp) (((dnp)->dn_flags & DNODE_FLAG_USED_BYTES) ? \
107           (dnp)->dn_used : (dnp)->dn_used << SPA_MINBLOCKSHIFT)
108 
109 #define   EPB(blkshift, typeshift)      (1 << (blkshift - typeshift))
110 
111 struct dmu_buf_impl;
112 struct objset;
113 struct zio;
114 
115 enum dnode_dirtycontext {
116           DN_UNDIRTIED,
117           DN_DIRTY_OPEN,
118           DN_DIRTY_SYNC
119 };
120 
121 /* Is dn_used in bytes?  if not, it's in multiples of SPA_MINBLOCKSIZE */
122 #define   DNODE_FLAG_USED_BYTES                   (1<<0)
123 #define   DNODE_FLAG_USERUSED_ACCOUNTED (1<<1)
124 
125 /* Does dnode have a SA spill blkptr in bonus? */
126 #define   DNODE_FLAG_SPILL_BLKPTR       (1<<2)
127 
128 typedef struct dnode_phys {
129           uint8_t dn_type;              /* dmu_object_type_t */
130           uint8_t dn_indblkshift;                 /* ln2(indirect block size) */
131           uint8_t dn_nlevels;           /* 1=dn_blkptr->data blocks */
132           uint8_t dn_nblkptr;           /* length of dn_blkptr */
133           uint8_t dn_bonustype;                   /* type of data in bonus buffer */
134           uint8_t   dn_checksum;                  /* ZIO_CHECKSUM type */
135           uint8_t   dn_compress;                  /* ZIO_COMPRESS type */
136           uint8_t dn_flags;             /* DNODE_FLAG_* */
137           uint16_t dn_datablkszsec;     /* data block size in 512b sectors */
138           uint16_t dn_bonuslen;                   /* length of dn_bonus */
139           uint8_t dn_pad2[4];
140 
141           /* accounting is protected by dn_dirty_mtx */
142           uint64_t dn_maxblkid;                   /* largest allocated block ID */
143           uint64_t dn_used;             /* bytes (or sectors) of disk space */
144 
145           uint64_t dn_pad3[4];
146 
147           blkptr_t dn_blkptr[1];
148           uint8_t dn_bonus[DN_MAX_BONUSLEN - sizeof (blkptr_t)];
149           blkptr_t dn_spill;
150 } dnode_phys_t;
151 
152 struct dnode {
153           /*
154            * Protects the structure of the dnode, including the number of levels
155            * of indirection (dn_nlevels), dn_maxblkid, and dn_next_*
156            */
157           krwlock_t dn_struct_rwlock;
158 
159           /* Our link on dn_objset->os_dnodes list; protected by os_lock.  */
160           list_node_t dn_link;
161 
162           /* immutable: */
163           struct objset *dn_objset;
164           uint64_t dn_object;
165           struct dmu_buf_impl *dn_dbuf;
166           struct dnode_handle *dn_handle;
167           dnode_phys_t *dn_phys; /* pointer into dn->dn_dbuf->db.db_data */
168 
169           /*
170            * Copies of stuff in dn_phys.  They're valid in the open
171            * context (eg. even before the dnode is first synced).
172            * Where necessary, these are protected by dn_struct_rwlock.
173            */
174           dmu_object_type_t dn_type;    /* object type */
175           uint16_t dn_bonuslen;                   /* bonus length */
176           uint8_t dn_bonustype;                   /* bonus type */
177           uint8_t dn_nblkptr;           /* number of blkptrs (immutable) */
178           uint8_t dn_checksum;                    /* ZIO_CHECKSUM type */
179           uint8_t dn_compress;                    /* ZIO_COMPRESS type */
180           uint8_t dn_nlevels;
181           uint8_t dn_indblkshift;
182           uint8_t dn_datablkshift;      /* zero if blksz not power of 2! */
183           uint8_t dn_moved;             /* Has this dnode been moved? */
184           uint16_t dn_datablkszsec;     /* in 512b sectors */
185           uint32_t dn_datablksz;                  /* in bytes */
186           uint64_t dn_maxblkid;
187           uint8_t dn_next_type[TXG_SIZE];
188           uint8_t dn_next_nblkptr[TXG_SIZE];
189           uint8_t dn_next_nlevels[TXG_SIZE];
190           uint8_t dn_next_indblkshift[TXG_SIZE];
191           uint8_t dn_next_bonustype[TXG_SIZE];
192           uint8_t dn_rm_spillblk[TXG_SIZE];       /* for removing spill blk */
193           uint16_t dn_next_bonuslen[TXG_SIZE];
194           uint32_t dn_next_blksz[TXG_SIZE];       /* next block size in bytes */
195 
196           /* protected by dn_dbufs_mtx; declared here to fill 32-bit hole */
197           uint32_t dn_dbufs_count;      /* count of dn_dbufs */
198 
199           /* protected by os_lock: */
200           list_node_t dn_dirty_link[TXG_SIZE];    /* next on dataset's dirty */
201 
202           /* protected by dn_mtx: */
203           kmutex_t dn_mtx;
204           list_t dn_dirty_records[TXG_SIZE];
205           struct range_tree *dn_free_ranges[TXG_SIZE];
206           uint64_t dn_allocated_txg;
207           uint64_t dn_free_txg;
208           uint64_t dn_assigned_txg;
209           kcondvar_t dn_notxholds;
210           enum dnode_dirtycontext dn_dirtyctx;
211           uint8_t *dn_dirtyctx_firstset;                    /* dbg: contents meaningless */
212 
213           /* protected by own devices */
214           refcount_t dn_tx_holds;
215           refcount_t dn_holds;
216 
217           kmutex_t dn_dbufs_mtx;
218           /*
219            * Descendent dbufs, ordered by dbuf_compare. Note that dn_dbufs
220            * can contain multiple dbufs of the same (level, blkid) when a
221            * dbuf is marked DB_EVICTING without being removed from
222            * dn_dbufs. To maintain the avl invariant that there cannot be
223            * duplicate entries, we order the dbufs by an arbitrary value -
224            * their address in memory. This means that dn_dbufs cannot be used to
225            * directly look up a dbuf. Instead, callers must use avl_walk, have
226            * a reference to the dbuf, or look up a non-existant node with
227            * db_state = DB_SEARCH (see dbuf_free_range for an example).
228            */
229           avl_tree_t dn_dbufs;
230 
231           /* protected by dn_struct_rwlock */
232           struct dmu_buf_impl *dn_bonus;          /* bonus buffer dbuf */
233 
234           boolean_t dn_have_spill;      /* have spill or are spilling */
235 
236           /* parent IO for current sync write */
237           zio_t *dn_zio;
238 
239           /* used in syncing context */
240           uint64_t dn_oldused;          /* old phys used bytes */
241           uint64_t dn_oldflags;         /* old phys dn_flags */
242           uint64_t dn_olduid, dn_oldgid;
243           uint64_t dn_newuid, dn_newgid;
244           int dn_id_flags;
245 
246           /* holds prefetch structure */
247           struct zfetch       dn_zfetch;
248 };
249 
250 /*
251  * Adds a level of indirection between the dbuf and the dnode to avoid
252  * iterating descendent dbufs in dnode_move(). Handles are not allocated
253  * individually, but as an array of child dnodes in dnode_hold_impl().
254  */
255 typedef struct dnode_handle {
256           /* Protects dnh_dnode from modification by dnode_move(). */
257           zrlock_t dnh_zrlock;
258           dnode_t *dnh_dnode;
259 } dnode_handle_t;
260 
261 typedef struct dnode_children {
262           dmu_buf_user_t dnc_dbu;                 /* User evict data */
263           size_t dnc_count;             /* number of children */
264           dnode_handle_t dnc_children[];          /* sized dynamically */
265 } dnode_children_t;
266 
267 typedef struct free_range {
268           avl_node_t fr_node;
269           uint64_t fr_blkid;
270           uint64_t fr_nblks;
271 } free_range_t;
272 
273 void dnode_special_open(struct objset *dd, dnode_phys_t *dnp,
274     uint64_t object, dnode_handle_t *dnh);
275 void dnode_special_close(dnode_handle_t *dnh);
276 
277 void dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx);
278 void dnode_setbonus_type(dnode_t *dn, dmu_object_type_t, dmu_tx_t *tx);
279 void dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx);
280 
281 int dnode_hold(struct objset *dd, uint64_t object,
282     void *ref, dnode_t **dnp);
283 int dnode_hold_impl(struct objset *dd, uint64_t object, int flag,
284     void *ref, dnode_t **dnp);
285 boolean_t dnode_add_ref(dnode_t *dn, void *ref);
286 void dnode_rele(dnode_t *dn, void *ref);
287 void dnode_rele_and_unlock(dnode_t *dn, void *tag);
288 void dnode_setdirty(dnode_t *dn, dmu_tx_t *tx);
289 void dnode_sync(dnode_t *dn, dmu_tx_t *tx);
290 void dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs,
291     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
292 void dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize,
293     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
294 void dnode_free(dnode_t *dn, dmu_tx_t *tx);
295 void dnode_byteswap(dnode_phys_t *dnp);
296 void dnode_buf_byteswap(void *buf, size_t size);
297 void dnode_verify(dnode_t *dn);
298 int dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx);
299 void dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx);
300 void dnode_diduse_space(dnode_t *dn, int64_t space);
301 void dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx);
302 void dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t);
303 uint64_t dnode_block_freed(dnode_t *dn, uint64_t blkid);
304 void dnode_init(void);
305 void dnode_fini(void);
306 int dnode_next_offset(dnode_t *dn, int flags, uint64_t *off,
307     int minlvl, uint64_t blkfill, uint64_t txg);
308 void dnode_evict_dbufs(dnode_t *dn);
309 void dnode_evict_bonus(dnode_t *dn);
310 
311 #define   DNODE_IS_CACHEABLE(_dn)                                                         \
312           ((_dn)->dn_objset->os_primary_cache == ZFS_CACHE_ALL ||               \
313           (DMU_OT_IS_METADATA((_dn)->dn_type) &&                                \
314           (_dn)->dn_objset->os_primary_cache == ZFS_CACHE_METADATA))
315 
316 #define   DNODE_META_IS_CACHEABLE(_dn)                                          \
317           ((_dn)->dn_objset->os_primary_cache == ZFS_CACHE_ALL ||               \
318           (_dn)->dn_objset->os_primary_cache == ZFS_CACHE_METADATA)
319 
320 #ifdef ZFS_DEBUG
321 
322 /*
323  * There should be a ## between the string literal and fmt, to make it
324  * clear that we're joining two strings together, but that piece of shit
325  * gcc doesn't support that preprocessor token.
326  */
327 #define   dprintf_dnode(dn, fmt, ...) do { \
328           if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
329           char __db_buf[32]; \
330           uint64_t __db_obj = (dn)->dn_object; \
331           if (__db_obj == DMU_META_DNODE_OBJECT) \
332                     (void) strcpy(__db_buf, "mdn"); \
333           else \
334                     (void) snprintf(__db_buf, sizeof (__db_buf), "%lld", \
335                         (u_longlong_t)__db_obj);\
336           dprintf_ds((dn)->dn_objset->os_dsl_dataset, "obj=%s " fmt, \
337               __db_buf, __VA_ARGS__); \
338           } \
339 _NOTE(CONSTCOND) } while (0)
340 
341 #define   DNODE_VERIFY(dn)              dnode_verify(dn)
342 #define   FREE_VERIFY(db, start, end, tx)         free_verify(db, start, end, tx)
343 
344 #else
345 
346 #define   dprintf_dnode(db, fmt, ...)
347 #define   DNODE_VERIFY(dn)
348 #define   FREE_VERIFY(db, start, end, tx)
349 
350 #endif
351 
352 #ifdef    __cplusplus
353 }
354 #endif
355 
356 #endif    /* _SYS_DNODE_H */
357