X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libbcachefs%2Fstr_hash.h;h=89fdb7c21134ebbb6c145a88ed5b1943ab54588a;hb=8d8a9f3e9bdd1d84fbbe0531e81977cc9044654a;hp=530cf0a49c847fba690f27ecf86ac46bff312ef9;hpb=8351bbc05bc163758d3410ce6d6cab8eb4441609;p=bcachefs-tools-debian diff --git a/libbcachefs/str_hash.h b/libbcachefs/str_hash.h index 530cf0a..89fdb7c 100644 --- a/libbcachefs/str_hash.h +++ b/libbcachefs/str_hash.h @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _BCACHEFS_STR_HASH_H #define _BCACHEFS_STR_HASH_H @@ -7,48 +8,68 @@ #include "error.h" #include "inode.h" #include "siphash.h" +#include "subvolume.h" #include "super.h" #include #include +#include + +typedef unsigned __bitwise bch_str_hash_flags_t; + +enum bch_str_hash_flags { + __BCH_HASH_SET_MUST_CREATE, + __BCH_HASH_SET_MUST_REPLACE, +}; + +#define BCH_HASH_SET_MUST_CREATE (__force bch_str_hash_flags_t) BIT(__BCH_HASH_SET_MUST_CREATE) +#define BCH_HASH_SET_MUST_REPLACE (__force bch_str_hash_flags_t) BIT(__BCH_HASH_SET_MUST_REPLACE) + +static inline enum bch_str_hash_type +bch2_str_hash_opt_to_type(struct bch_fs *c, enum bch_str_hash_opts opt) +{ + switch (opt) { + case BCH_STR_HASH_OPT_crc32c: + return BCH_STR_HASH_crc32c; + case BCH_STR_HASH_OPT_crc64: + return BCH_STR_HASH_crc64; + case BCH_STR_HASH_OPT_siphash: + return c->sb.features & (1ULL << BCH_FEATURE_new_siphash) + ? BCH_STR_HASH_siphash + : BCH_STR_HASH_siphash_old; + default: + BUG(); + } +} struct bch_hash_info { u8 type; - union { - __le64 crc_key; - SIPHASH_KEY siphash_key; - }; + /* + * For crc32 or crc64 string hashes the first key value of + * the siphash_key (k0) is used as the key. + */ + SIPHASH_KEY siphash_key; }; static inline struct bch_hash_info -bch2_hash_info_init(struct bch_fs *c, - const struct bch_inode_unpacked *bi) +bch2_hash_info_init(struct bch_fs *c, const struct bch_inode_unpacked *bi) { /* XXX ick */ struct bch_hash_info info = { .type = (bi->bi_flags >> INODE_STR_HASH_OFFSET) & - ~(~0U << INODE_STR_HASH_BITS) + ~(~0U << INODE_STR_HASH_BITS), + .siphash_key = { .k0 = bi->bi_hash_seed } }; - switch (info.type) { - case BCH_STR_HASH_CRC32C: - case BCH_STR_HASH_CRC64: - info.crc_key = bi->bi_hash_seed; - break; - case BCH_STR_HASH_SIPHASH: { + if (unlikely(info.type == BCH_STR_HASH_siphash_old)) { SHASH_DESC_ON_STACK(desc, c->sha256); - u8 digest[crypto_shash_digestsize(c->sha256)]; + u8 digest[SHA256_DIGEST_SIZE]; desc->tfm = c->sha256; - desc->flags = 0; crypto_shash_digest(desc, (void *) &bi->bi_hash_seed, sizeof(bi->bi_hash_seed), digest); memcpy(&info.siphash_key, digest, sizeof(info.siphash_key)); - break; - } - default: - BUG(); } return info; @@ -66,13 +87,16 @@ static inline void bch2_str_hash_init(struct bch_str_hash_ctx *ctx, const struct bch_hash_info *info) { switch (info->type) { - case BCH_STR_HASH_CRC32C: - ctx->crc32c = crc32c(~0, &info->crc_key, sizeof(info->crc_key)); + case BCH_STR_HASH_crc32c: + ctx->crc32c = crc32c(~0, &info->siphash_key.k0, + sizeof(info->siphash_key.k0)); break; - case BCH_STR_HASH_CRC64: - ctx->crc64 = bch2_crc64_update(~0, &info->crc_key, sizeof(info->crc_key)); + case BCH_STR_HASH_crc64: + ctx->crc64 = crc64_be(~0, &info->siphash_key.k0, + sizeof(info->siphash_key.k0)); break; - case BCH_STR_HASH_SIPHASH: + case BCH_STR_HASH_siphash_old: + case BCH_STR_HASH_siphash: SipHash24_Init(&ctx->siphash, &info->siphash_key); break; default: @@ -85,13 +109,14 @@ static inline void bch2_str_hash_update(struct bch_str_hash_ctx *ctx, const void *data, size_t len) { switch (info->type) { - case BCH_STR_HASH_CRC32C: + case BCH_STR_HASH_crc32c: ctx->crc32c = crc32c(ctx->crc32c, data, len); break; - case BCH_STR_HASH_CRC64: - ctx->crc64 = bch2_crc64_update(ctx->crc64, data, len); + case BCH_STR_HASH_crc64: + ctx->crc64 = crc64_be(ctx->crc64, data, len); break; - case BCH_STR_HASH_SIPHASH: + case BCH_STR_HASH_siphash_old: + case BCH_STR_HASH_siphash: SipHash24_Update(&ctx->siphash, data, len); break; default: @@ -103,11 +128,12 @@ static inline u64 bch2_str_hash_end(struct bch_str_hash_ctx *ctx, const struct bch_hash_info *info) { switch (info->type) { - case BCH_STR_HASH_CRC32C: + case BCH_STR_HASH_crc32c: return ctx->crc32c; - case BCH_STR_HASH_CRC64: + case BCH_STR_HASH_crc64: return ctx->crc64 >> 1; - case BCH_STR_HASH_SIPHASH: + case BCH_STR_HASH_siphash_old: + case BCH_STR_HASH_siphash: return SipHash24_End(&ctx->siphash) >> 1; default: BUG(); @@ -117,290 +143,238 @@ static inline u64 bch2_str_hash_end(struct bch_str_hash_ctx *ctx, struct bch_hash_desc { enum btree_id btree_id; u8 key_type; - u8 whiteout_type; u64 (*hash_key)(const struct bch_hash_info *, const void *); u64 (*hash_bkey)(const struct bch_hash_info *, struct bkey_s_c); bool (*cmp_key)(struct bkey_s_c, const void *); bool (*cmp_bkey)(struct bkey_s_c, struct bkey_s_c); + bool (*is_visible)(subvol_inum inum, struct bkey_s_c); }; -static inline struct bkey_s_c -bch2_hash_lookup_at(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct btree_iter *iter, const void *search) +static inline bool is_visible_key(struct bch_hash_desc desc, subvol_inum inum, struct bkey_s_c k) { - u64 inode = iter->pos.inode; - - do { - struct bkey_s_c k = bch2_btree_iter_peek_with_holes(iter); - - if (btree_iter_err(k)) - return k; - - if (k.k->type == desc.key_type) { - if (!desc.cmp_key(k, search)) - return k; - } else if (k.k->type == desc.whiteout_type) { - ; - } else { - /* hole, not found */ - break; - } - - bch2_btree_iter_advance_pos(iter); - } while (iter->pos.inode == inode); - - return bkey_s_c_err(-ENOENT); + return k.k->type == desc.key_type && + (!desc.is_visible || + !inum.inum || + desc.is_visible(inum, k)); } -static inline struct bkey_s_c -bch2_hash_lookup_bkey_at(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct btree_iter *iter, struct bkey_s_c search) +static __always_inline int +bch2_hash_lookup(struct btree_trans *trans, + struct btree_iter *iter, + const struct bch_hash_desc desc, + const struct bch_hash_info *info, + subvol_inum inum, const void *key, + unsigned flags) { - u64 inode = iter->pos.inode; - - do { - struct bkey_s_c k = bch2_btree_iter_peek_with_holes(iter); - - if (btree_iter_err(k)) - return k; + struct bkey_s_c k; + u32 snapshot; + int ret; - if (k.k->type == desc.key_type) { - if (!desc.cmp_bkey(k, search)) - return k; - } else if (k.k->type == desc.whiteout_type) { + ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot); + if (ret) + return ret; + + for_each_btree_key_upto_norestart(trans, *iter, desc.btree_id, + SPOS(inum.inum, desc.hash_key(info, key), snapshot), + POS(inum.inum, U64_MAX), + BTREE_ITER_SLOTS|flags, k, ret) { + if (is_visible_key(desc, inum, k)) { + if (!desc.cmp_key(k, key)) + return 0; + } else if (k.k->type == KEY_TYPE_hash_whiteout) { ; } else { /* hole, not found */ break; } + } + bch2_trans_iter_exit(trans, iter); - bch2_btree_iter_advance_pos(iter); - } while (iter->pos.inode == inode); - - return bkey_s_c_err(-ENOENT); + return ret ?: -BCH_ERR_ENOENT_str_hash_lookup; } -static inline struct bkey_s_c -bch2_hash_lookup(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct bch_fs *c, u64 inode, - struct btree_iter *iter, const void *key) +static __always_inline int +bch2_hash_hole(struct btree_trans *trans, + struct btree_iter *iter, + const struct bch_hash_desc desc, + const struct bch_hash_info *info, + subvol_inum inum, const void *key) { - bch2_btree_iter_init(iter, c, desc.btree_id, - POS(inode, desc.hash_key(info, key)), 0); + struct bkey_s_c k; + u32 snapshot; + int ret; - return bch2_hash_lookup_at(desc, info, iter, key); -} + ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot); + if (ret) + return ret; -static inline struct bkey_s_c -bch2_hash_lookup_intent(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct bch_fs *c, u64 inode, - struct btree_iter *iter, const void *key) -{ - bch2_btree_iter_init(iter, c, desc.btree_id, - POS(inode, desc.hash_key(info, key)), - BTREE_ITER_INTENT); + for_each_btree_key_upto_norestart(trans, *iter, desc.btree_id, + SPOS(inum.inum, desc.hash_key(info, key), snapshot), + POS(inum.inum, U64_MAX), + BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) + if (!is_visible_key(desc, inum, k)) + return 0; + bch2_trans_iter_exit(trans, iter); - return bch2_hash_lookup_at(desc, info, iter, key); + return ret ?: -BCH_ERR_ENOSPC_str_hash_create; } -static inline struct bkey_s_c -bch2_hash_hole_at(const struct bch_hash_desc desc, struct btree_iter *iter) +static __always_inline +int bch2_hash_needs_whiteout(struct btree_trans *trans, + const struct bch_hash_desc desc, + const struct bch_hash_info *info, + struct btree_iter *start) { - while (1) { - struct bkey_s_c k = bch2_btree_iter_peek_with_holes(iter); + struct btree_iter iter; + struct bkey_s_c k; + int ret; - if (btree_iter_err(k)) - return k; + bch2_trans_copy_iter(&iter, start); - if (k.k->type != desc.key_type) - return k; + bch2_btree_iter_advance(&iter); - /* hash collision, keep going */ - bch2_btree_iter_advance_pos(iter); - if (iter->pos.inode != k.k->p.inode) - return bkey_s_c_err(-ENOENT); - } -} + for_each_btree_key_continue_norestart(iter, BTREE_ITER_SLOTS, k, ret) { + if (k.k->type != desc.key_type && + k.k->type != KEY_TYPE_hash_whiteout) + break; -static inline struct bkey_s_c bch2_hash_hole(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct bch_fs *c, u64 inode, - struct btree_iter *iter, - const void *key) -{ - bch2_btree_iter_init(iter, c, desc.btree_id, - POS(inode, desc.hash_key(info, key)), - BTREE_ITER_INTENT); + if (k.k->type == desc.key_type && + desc.hash_bkey(info, k) <= start->pos.offset) { + ret = 1; + break; + } + } - return bch2_hash_hole_at(desc, iter); + bch2_trans_iter_exit(trans, &iter); + return ret; } -static inline int bch2_hash_needs_whiteout(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct btree_iter *iter, - struct btree_iter *start) +static __always_inline +int bch2_hash_set_snapshot(struct btree_trans *trans, + const struct bch_hash_desc desc, + const struct bch_hash_info *info, + subvol_inum inum, u32 snapshot, + struct bkey_i *insert, + bch_str_hash_flags_t str_hash_flags, + int update_flags) { - bch2_btree_iter_set_pos(iter, - btree_type_successor(start->btree_id, start->pos)); + struct btree_iter iter, slot = { NULL }; + struct bkey_s_c k; + bool found = false; + int ret; - while (1) { - struct bkey_s_c k = bch2_btree_iter_peek_with_holes(iter); - int ret = btree_iter_err(k); + for_each_btree_key_upto_norestart(trans, iter, desc.btree_id, + SPOS(insert->k.p.inode, + desc.hash_bkey(info, bkey_i_to_s_c(insert)), + snapshot), + POS(insert->k.p.inode, U64_MAX), + BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) { + if (is_visible_key(desc, inum, k)) { + if (!desc.cmp_bkey(k, bkey_i_to_s_c(insert))) + goto found; + + /* hash collision: */ + continue; + } - if (ret) - return ret; + if (!slot.path && + !(str_hash_flags & BCH_HASH_SET_MUST_REPLACE)) + bch2_trans_copy_iter(&slot, &iter); - if (k.k->type != desc.key_type && - k.k->type != desc.whiteout_type) - return false; + if (k.k->type != KEY_TYPE_hash_whiteout) + goto not_found; + } - if (k.k->type == desc.key_type && - desc.hash_bkey(info, k) <= start->pos.offset) - return true; + if (!ret) + ret = -BCH_ERR_ENOSPC_str_hash_create; +out: + bch2_trans_iter_exit(trans, &slot); + bch2_trans_iter_exit(trans, &iter); + + return ret; +found: + found = true; +not_found: + + if (!found && (str_hash_flags & BCH_HASH_SET_MUST_REPLACE)) { + ret = -BCH_ERR_ENOENT_str_hash_set_must_replace; + } else if (found && (str_hash_flags & BCH_HASH_SET_MUST_CREATE)) { + ret = -EEXIST; + } else { + if (!found && slot.path) + swap(iter, slot); - bch2_btree_iter_advance_pos(iter); + insert->k.p = iter.pos; + ret = bch2_trans_update(trans, &iter, insert, update_flags); } + + goto out; } -static inline int bch2_hash_set(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct bch_fs *c, u64 inode, - u64 *journal_seq, - struct bkey_i *insert, int flags) +static __always_inline +int bch2_hash_set(struct btree_trans *trans, + const struct bch_hash_desc desc, + const struct bch_hash_info *info, + subvol_inum inum, + struct bkey_i *insert, + bch_str_hash_flags_t str_hash_flags) { - struct btree_iter iter, hashed_slot; - struct bkey_s_c k; + u32 snapshot; int ret; - bch2_btree_iter_init(&hashed_slot, c, desc.btree_id, - POS(inode, desc.hash_bkey(info, bkey_i_to_s_c(insert))), - BTREE_ITER_INTENT); - bch2_btree_iter_init(&iter, c, desc.btree_id, hashed_slot.pos, - BTREE_ITER_INTENT); - bch2_btree_iter_link(&hashed_slot, &iter); -retry: - /* - * On hash collision, we have to keep the slot we hashed to locked while - * we do the insert - to avoid racing with another thread deleting - * whatever's in the slot we hashed to: - */ - ret = bch2_btree_iter_traverse(&hashed_slot); + ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot); if (ret) - goto err; + return ret; - /* - * On -EINTR/retry, we dropped locks - always restart from the slot we - * hashed to: - */ - bch2_btree_iter_copy(&iter, &hashed_slot); + insert->k.p.inode = inum.inum; - k = bch2_hash_lookup_bkey_at(desc, info, &iter, bkey_i_to_s_c(insert)); - - ret = btree_iter_err(k); - if (ret == -ENOENT) { - if (flags & BCH_HASH_SET_MUST_REPLACE) { - ret = -ENOENT; - goto err; - } - - /* - * Not found, so we're now looking for any open - * slot - we might have skipped over a whiteout - * that we could have used, so restart from the - * slot we hashed to: - */ - bch2_btree_iter_copy(&iter, &hashed_slot); - k = bch2_hash_hole_at(desc, &iter); - if ((ret = btree_iter_err(k))) - goto err; - } else if (!ret) { - if (flags & BCH_HASH_SET_MUST_CREATE) { - ret = -EEXIST; - goto err; - } - } else { - goto err; - } - - insert->k.p = iter.pos; - ret = bch2_btree_insert_at(c, NULL, NULL, journal_seq, - BTREE_INSERT_ATOMIC|flags, - BTREE_INSERT_ENTRY(&iter, insert)); -err: - if (ret == -EINTR) - goto retry; - - /* - * On successful insert, we don't want to clobber ret with error from - * iter: - */ - bch2_btree_iter_unlock(&iter); - bch2_btree_iter_unlock(&hashed_slot); - return ret; + return bch2_hash_set_snapshot(trans, desc, info, inum, + snapshot, insert, str_hash_flags, 0); } -static inline int bch2_hash_delete_at(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct btree_iter *iter, - u64 *journal_seq) +static __always_inline +int bch2_hash_delete_at(struct btree_trans *trans, + const struct bch_hash_desc desc, + const struct bch_hash_info *info, + struct btree_iter *iter, + unsigned update_flags) { - struct btree_iter whiteout_iter; - struct bkey_i delete; - int ret = -ENOENT; + struct bkey_i *delete; + int ret; - bch2_btree_iter_init(&whiteout_iter, iter->c, desc.btree_id, - iter->pos, 0); - bch2_btree_iter_link(iter, &whiteout_iter); + delete = bch2_trans_kmalloc(trans, sizeof(*delete)); + ret = PTR_ERR_OR_ZERO(delete); + if (ret) + return ret; - ret = bch2_hash_needs_whiteout(desc, info, &whiteout_iter, iter); + ret = bch2_hash_needs_whiteout(trans, desc, info, iter); if (ret < 0) - goto err; - - bkey_init(&delete.k); - delete.k.p = iter->pos; - delete.k.type = ret ? desc.whiteout_type : KEY_TYPE_DELETED; - - ret = bch2_btree_insert_at(iter->c, NULL, NULL, journal_seq, - BTREE_INSERT_NOFAIL| - BTREE_INSERT_ATOMIC, - BTREE_INSERT_ENTRY(iter, &delete)); -err: - bch2_btree_iter_unlink(&whiteout_iter); - return ret; + return ret; + + bkey_init(&delete->k); + delete->k.p = iter->pos; + delete->k.type = ret ? KEY_TYPE_hash_whiteout : KEY_TYPE_deleted; + + return bch2_trans_update(trans, iter, delete, update_flags); } -static inline int bch2_hash_delete(const struct bch_hash_desc desc, - const struct bch_hash_info *info, - struct bch_fs *c, u64 inode, - u64 *journal_seq, const void *key) +static __always_inline +int bch2_hash_delete(struct btree_trans *trans, + const struct bch_hash_desc desc, + const struct bch_hash_info *info, + subvol_inum inum, const void *key) { - struct btree_iter iter, whiteout_iter; - struct bkey_s_c k; - int ret = -ENOENT; - - bch2_btree_iter_init(&iter, c, desc.btree_id, - POS(inode, desc.hash_key(info, key)), - BTREE_ITER_INTENT); - bch2_btree_iter_init(&whiteout_iter, c, desc.btree_id, - POS(inode, desc.hash_key(info, key)), 0); - bch2_btree_iter_link(&iter, &whiteout_iter); -retry: - k = bch2_hash_lookup_at(desc, info, &iter, key); - if ((ret = btree_iter_err(k))) - goto err; - - ret = bch2_hash_delete_at(desc, info, &iter, journal_seq); -err: - if (ret == -EINTR) - goto retry; - - bch2_btree_iter_unlock(&whiteout_iter); - bch2_btree_iter_unlock(&iter); + struct btree_iter iter; + int ret; + + ret = bch2_hash_lookup(trans, &iter, desc, info, inum, key, + BTREE_ITER_INTENT); + if (ret) + return ret; + + ret = bch2_hash_delete_at(trans, desc, info, &iter, 0); + bch2_trans_iter_exit(trans, &iter); return ret; }