From d702f86eaf5aba13762f436152026ba0befa1a23 Mon Sep 17 00:00:00 2001 From: Rob Norris Date: Sat, 18 Nov 2023 21:32:16 +1100 Subject: brt: lift internal definitions into _impl header So that zdb (and others!) can get at the BRT on-disk structures. Reviewed-by: Alexander Motin Reviewed-by: Kay Pedersen Reviewed-by: Brian Behlendorf Signed-off-by: Rob Norris Closes #15541 --- include/Makefile.am | 1 + include/sys/brt_impl.h | 199 +++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 200 insertions(+) create mode 100644 include/sys/brt_impl.h (limited to 'include') diff --git a/include/Makefile.am b/include/Makefile.am index 569de6dfa..5f38f6ac6 100644 --- a/include/Makefile.am +++ b/include/Makefile.am @@ -33,6 +33,7 @@ COMMON_H = \ sys/bqueue.h \ sys/btree.h \ sys/brt.h \ + sys/brt_impl.h \ sys/dataset_kstats.h \ sys/dbuf.h \ sys/ddt.h \ diff --git a/include/sys/brt_impl.h b/include/sys/brt_impl.h new file mode 100644 index 000000000..9cc06fbb2 --- /dev/null +++ b/include/sys/brt_impl.h @@ -0,0 +1,199 @@ +/* + * 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 https://opensource.org/licenses/CDDL-1.0. + * 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) 2020, 2021, 2022 by Pawel Jakub Dawidek + */ + +#ifndef _SYS_BRT_IMPL_H +#define _SYS_BRT_IMPL_H + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * BRT - Block Reference Table. + */ +#define BRT_OBJECT_VDEV_PREFIX "com.fudosecurity:brt:vdev:" + +/* + * We divide each VDEV into 16MB chunks. Each chunk is represented in memory + * by a 16bit counter, thus 1TB VDEV requires 128kB of memory: (1TB / 16MB) * 2B + * Each element in this array represents how many BRT entries do we have in this + * chunk of storage. We always load this entire array into memory and update as + * needed. By having it in memory we can quickly tell (during zio_free()) if + * there are any BRT entries that we might need to update. + * + * This value cannot be larger than 16MB, at least as long as we support + * 512 byte block sizes. With 512 byte block size we can have exactly + * 32768 blocks in 16MB. In 32MB we could have 65536 blocks, which is one too + * many for a 16bit counter. + */ +#define BRT_RANGESIZE (16 * 1024 * 1024) +_Static_assert(BRT_RANGESIZE / SPA_MINBLOCKSIZE <= UINT16_MAX, + "BRT_RANGESIZE is too large."); +/* + * We don't want to update the whole structure every time. Maintain bitmap + * of dirty blocks within the regions, so that a single bit represents a + * block size of entcounts. For example if we have a 1PB vdev then all + * entcounts take 128MB of memory ((64TB / 16MB) * 2B). We can divide this + * 128MB array of entcounts into 32kB disk blocks, as we don't want to update + * the whole 128MB on disk when we have updated only a single entcount. + * We maintain a bitmap where each 32kB disk block within 128MB entcounts array + * is represented by a single bit. This gives us 4096 bits. A set bit in the + * bitmap means that we had a change in at least one of the 16384 entcounts + * that reside on a 32kB disk block (32kB / sizeof (uint16_t)). + */ +#define BRT_BLOCKSIZE (32 * 1024) +#define BRT_RANGESIZE_TO_NBLOCKS(size) \ + (((size) - 1) / BRT_BLOCKSIZE / sizeof (uint16_t) + 1) + +#define BRT_LITTLE_ENDIAN 0 +#define BRT_BIG_ENDIAN 1 +#ifdef _ZFS_LITTLE_ENDIAN +#define BRT_NATIVE_BYTEORDER BRT_LITTLE_ENDIAN +#define BRT_NON_NATIVE_BYTEORDER BRT_BIG_ENDIAN +#else +#define BRT_NATIVE_BYTEORDER BRT_BIG_ENDIAN +#define BRT_NON_NATIVE_BYTEORDER BRT_LITTLE_ENDIAN +#endif + +typedef struct brt_vdev_phys { + uint64_t bvp_mos_entries; + uint64_t bvp_size; + uint64_t bvp_byteorder; + uint64_t bvp_totalcount; + uint64_t bvp_rangesize; + uint64_t bvp_usedspace; + uint64_t bvp_savedspace; +} brt_vdev_phys_t; + +typedef struct brt_vdev { + /* + * VDEV id. + */ + uint64_t bv_vdevid; + /* + * Is the structure initiated? + * (bv_entcount and bv_bitmap are allocated?) + */ + boolean_t bv_initiated; + /* + * Object number in the MOS for the entcount array and brt_vdev_phys. + */ + uint64_t bv_mos_brtvdev; + /* + * Object number in the MOS for the entries table. + */ + uint64_t bv_mos_entries; + /* + * Entries to sync. + */ + avl_tree_t bv_tree; + /* + * Does the bv_entcount[] array needs byte swapping? + */ + boolean_t bv_need_byteswap; + /* + * Number of entries in the bv_entcount[] array. + */ + uint64_t bv_size; + /* + * This is the array with BRT entry count per BRT_RANGESIZE. + */ + uint16_t *bv_entcount; + /* + * Sum of all bv_entcount[]s. + */ + uint64_t bv_totalcount; + /* + * Space on disk occupied by cloned blocks (without compression). + */ + uint64_t bv_usedspace; + /* + * How much additional space would be occupied without block cloning. + */ + uint64_t bv_savedspace; + /* + * brt_vdev_phys needs updating on disk. + */ + boolean_t bv_meta_dirty; + /* + * bv_entcount[] needs updating on disk. + */ + boolean_t bv_entcount_dirty; + /* + * bv_entcount[] potentially can be a bit too big to sychronize it all + * when we just changed few entcounts. The fields below allow us to + * track updates to bv_entcount[] array since the last sync. + * A single bit in the bv_bitmap represents as many entcounts as can + * fit into a single BRT_BLOCKSIZE. + * For example we have 65536 entcounts in the bv_entcount array + * (so the whole array is 128kB). We updated bv_entcount[2] and + * bv_entcount[5]. In that case only first bit in the bv_bitmap will + * be set and we will write only first BRT_BLOCKSIZE out of 128kB. + */ + ulong_t *bv_bitmap; + uint64_t bv_nblocks; +} brt_vdev_t; + +/* + * In-core brt + */ +typedef struct brt { + krwlock_t brt_lock; + spa_t *brt_spa; +#define brt_mos brt_spa->spa_meta_objset + uint64_t brt_rangesize; + uint64_t brt_usedspace; + uint64_t brt_savedspace; + avl_tree_t brt_pending_tree[TXG_SIZE]; + kmutex_t brt_pending_lock[TXG_SIZE]; + /* Sum of all entries across all bv_trees. */ + uint64_t brt_nentries; + brt_vdev_t *brt_vdevs; + uint64_t brt_nvdevs; +} brt_t; + +/* Size of bre_offset / sizeof (uint64_t). */ +#define BRT_KEY_WORDS (1) + +/* + * In-core brt entry. + * On-disk we use bre_offset as the key and bre_refcount as the value. + */ +typedef struct brt_entry { + uint64_t bre_offset; + uint64_t bre_refcount; + avl_node_t bre_node; +} brt_entry_t; + +typedef struct brt_pending_entry { + blkptr_t bpe_bp; + int bpe_count; + avl_node_t bpe_node; +} brt_pending_entry_t; + +#ifdef __cplusplus +} +#endif + +#endif /* _SYS_BRT_IMPL_H */ -- cgit v1.2.3