/* * 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) 2014 Spectra Logic Corporation, All rights reserved. */ #ifndef _SYS_ZAP_LEAF_H #define _SYS_ZAP_LEAF_H #include <sys/zap.h> #ifdef __cplusplus extern "C" { #endif struct zap; struct zap_name; struct zap_stats; #define ZAP_LEAF_MAGIC 0x2AB1EAF /* chunk size = 24 bytes */ #define ZAP_LEAF_CHUNKSIZE 24 /* * The amount of space available for chunks is: * block size (1<<l->l_bs) - hash entry size (2) * number of hash * entries - header space (2*chunksize) */ #define ZAP_LEAF_NUMCHUNKS(l) \ (((1<<(l)->l_bs) - 2*ZAP_LEAF_HASH_NUMENTRIES(l)) / \ ZAP_LEAF_CHUNKSIZE - 2) /* * The amount of space within the chunk available for the array is: * chunk size - space for type (1) - space for next pointer (2) */ #define ZAP_LEAF_ARRAY_BYTES (ZAP_LEAF_CHUNKSIZE - 3) #define ZAP_LEAF_ARRAY_NCHUNKS(bytes) \ (((bytes)+ZAP_LEAF_ARRAY_BYTES-1)/ZAP_LEAF_ARRAY_BYTES) /* * Low water mark: when there are only this many chunks free, start * growing the ptrtbl. Ideally, this should be larger than a * "reasonably-sized" entry. 20 chunks is more than enough for the * largest directory entry (MAXNAMELEN (256) byte name, 8-byte value), * while still being only around 3% for 16k blocks. */ #define ZAP_LEAF_LOW_WATER (20) /* * The leaf hash table has block size / 2^5 (32) number of entries, * which should be more than enough for the maximum number of entries, * which is less than block size / CHUNKSIZE (24) / minimum number of * chunks per entry (3). */ #define ZAP_LEAF_HASH_SHIFT(l) ((l)->l_bs - 5) #define ZAP_LEAF_HASH_NUMENTRIES(l) (1 << ZAP_LEAF_HASH_SHIFT(l)) /* * The chunks start immediately after the hash table. The end of the * hash table is at l_hash + HASH_NUMENTRIES, which we simply cast to a * chunk_t. */ #define ZAP_LEAF_CHUNK(l, idx) \ ((zap_leaf_chunk_t *) \ (zap_leaf_phys(l)->l_hash + ZAP_LEAF_HASH_NUMENTRIES(l)))[idx] #define ZAP_LEAF_ENTRY(l, idx) (&ZAP_LEAF_CHUNK(l, idx).l_entry) typedef enum zap_chunk_type { ZAP_CHUNK_FREE = 253, ZAP_CHUNK_ENTRY = 252, ZAP_CHUNK_ARRAY = 251, ZAP_CHUNK_TYPE_MAX = 250 } zap_chunk_type_t; #define ZLF_ENTRIES_CDSORTED (1<<0) /* * TAKE NOTE: * If zap_leaf_phys_t is modified, zap_leaf_byteswap() must be modified. */ typedef struct zap_leaf_phys { struct zap_leaf_header { /* Public to ZAP */ uint64_t lh_block_type; /* ZBT_LEAF */ uint64_t lh_pad1; uint64_t lh_prefix; /* hash prefix of this leaf */ uint32_t lh_magic; /* ZAP_LEAF_MAGIC */ uint16_t lh_nfree; /* number free chunks */ uint16_t lh_nentries; /* number of entries */ uint16_t lh_prefix_len; /* num bits used to id this */ /* Private to zap_leaf */ uint16_t lh_freelist; /* chunk head of free list */ uint8_t lh_flags; /* ZLF_* flags */ uint8_t lh_pad2[11]; } l_hdr; /* 2 24-byte chunks */ /* * The header is followed by a hash table with * ZAP_LEAF_HASH_NUMENTRIES(zap) entries. The hash table is * followed by an array of ZAP_LEAF_NUMCHUNKS(zap) * zap_leaf_chunk structures. These structures are accessed * with the ZAP_LEAF_CHUNK() macro. */ uint16_t l_hash[1]; } zap_leaf_phys_t; typedef union zap_leaf_chunk { struct zap_leaf_entry { uint8_t le_type; /* always ZAP_CHUNK_ENTRY */ uint8_t le_value_intlen; /* size of value's ints */ uint16_t le_next; /* next entry in hash chain */ uint16_t le_name_chunk; /* first chunk of the name */ uint16_t le_name_numints; /* ints in name (incl null) */ uint16_t le_value_chunk; /* first chunk of the value */ uint16_t le_value_numints; /* value length in ints */ uint32_t le_cd; /* collision differentiator */ uint64_t le_hash; /* hash value of the name */ } l_entry; struct zap_leaf_array { uint8_t la_type; /* always ZAP_CHUNK_ARRAY */ uint8_t la_array[ZAP_LEAF_ARRAY_BYTES]; uint16_t la_next; /* next blk or CHAIN_END */ } l_array; struct zap_leaf_free { uint8_t lf_type; /* always ZAP_CHUNK_FREE */ uint8_t lf_pad[ZAP_LEAF_ARRAY_BYTES]; uint16_t lf_next; /* next in free list, or CHAIN_END */ } l_free; } zap_leaf_chunk_t; typedef struct zap_leaf { dmu_buf_user_t l_dbu; krwlock_t l_rwlock; uint64_t l_blkid; /* 1<<ZAP_BLOCK_SHIFT byte block off */ int l_bs; /* block size shift */ dmu_buf_t *l_dbuf; } zap_leaf_t; inline zap_leaf_phys_t * zap_leaf_phys(zap_leaf_t *l) { return (l->l_dbuf->db_data); } typedef struct zap_entry_handle { /* Set by zap_leaf and public to ZAP */ uint64_t zeh_num_integers; uint64_t zeh_hash; uint32_t zeh_cd; uint8_t zeh_integer_size; /* Private to zap_leaf */ uint16_t zeh_fakechunk; uint16_t *zeh_chunkp; zap_leaf_t *zeh_leaf; } zap_entry_handle_t; /* * Return a handle to the named entry, or ENOENT if not found. The hash * value must equal zap_hash(name). */ extern int zap_leaf_lookup(zap_leaf_t *l, struct zap_name *zn, zap_entry_handle_t *zeh); /* * Return a handle to the entry with this hash+cd, or the entry with the * next closest hash+cd. */ extern int zap_leaf_lookup_closest(zap_leaf_t *l, uint64_t hash, uint32_t cd, zap_entry_handle_t *zeh); /* * Read the first num_integers in the attribute. Integer size * conversion will be done without sign extension. Return EINVAL if * integer_size is too small. Return EOVERFLOW if there are more than * num_integers in the attribute. */ extern int zap_entry_read(const zap_entry_handle_t *zeh, uint8_t integer_size, uint64_t num_integers, void *buf); extern int zap_entry_read_name(struct zap *zap, const zap_entry_handle_t *zeh, uint16_t buflen, char *buf); /* * Replace the value of an existing entry. * * May fail if it runs out of space (ENOSPC). */ extern int zap_entry_update(zap_entry_handle_t *zeh, uint8_t integer_size, uint64_t num_integers, const void *buf); /* * Remove an entry. */ extern void zap_entry_remove(zap_entry_handle_t *zeh); /* * Create an entry. An equal entry must not exist, and this entry must * belong in this leaf (according to its hash value). Fills in the * entry handle on success. Returns 0 on success or ENOSPC on failure. */ extern int zap_entry_create(zap_leaf_t *l, struct zap_name *zn, uint32_t cd, uint8_t integer_size, uint64_t num_integers, const void *buf, zap_entry_handle_t *zeh); /* Determine whether there is another entry with the same normalized form. */ extern boolean_t zap_entry_normalization_conflict(zap_entry_handle_t *zeh, struct zap_name *zn, const char *name, struct zap *zap); /* * Other stuff. */ extern void zap_leaf_init(zap_leaf_t *l, boolean_t sort); extern void zap_leaf_byteswap(zap_leaf_phys_t *buf, int len); extern void zap_leaf_split(zap_leaf_t *l, zap_leaf_t *nl, boolean_t sort); extern void zap_leaf_stats(struct zap *zap, zap_leaf_t *l, struct zap_stats *zs); #ifdef __cplusplus } #endif #endif /* _SYS_ZAP_LEAF_H */
