From 34996e42f82bfd60bc2c191e5cae3c6ab233ec6c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 7 Aug 2024 15:11:27 +0200 Subject: Merging upstream version 6.9.7. Signed-off-by: Daniel Baumann --- drivers/md/dm-vdo/indexer/hash-utils.h | 66 ++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 drivers/md/dm-vdo/indexer/hash-utils.h (limited to 'drivers/md/dm-vdo/indexer/hash-utils.h') diff --git a/drivers/md/dm-vdo/indexer/hash-utils.h b/drivers/md/dm-vdo/indexer/hash-utils.h new file mode 100644 index 0000000000..6a8dd8ffea --- /dev/null +++ b/drivers/md/dm-vdo/indexer/hash-utils.h @@ -0,0 +1,66 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright 2023 Red Hat + */ + +#ifndef UDS_HASH_UTILS_H +#define UDS_HASH_UTILS_H + +#include "numeric.h" + +#include "geometry.h" +#include "indexer.h" + +/* Utilities for extracting portions of a request name for various uses. */ + +/* How various portions of a record name are apportioned. */ +enum { + VOLUME_INDEX_BYTES_OFFSET = 0, + VOLUME_INDEX_BYTES_COUNT = 8, + CHAPTER_INDEX_BYTES_OFFSET = 8, + CHAPTER_INDEX_BYTES_COUNT = 6, + SAMPLE_BYTES_OFFSET = 14, + SAMPLE_BYTES_COUNT = 2, +}; + +static inline u64 uds_extract_chapter_index_bytes(const struct uds_record_name *name) +{ + const u8 *chapter_bits = &name->name[CHAPTER_INDEX_BYTES_OFFSET]; + u64 bytes = (u64) get_unaligned_be16(chapter_bits) << 32; + + bytes |= get_unaligned_be32(chapter_bits + 2); + return bytes; +} + +static inline u64 uds_extract_volume_index_bytes(const struct uds_record_name *name) +{ + return get_unaligned_be64(&name->name[VOLUME_INDEX_BYTES_OFFSET]); +} + +static inline u32 uds_extract_sampling_bytes(const struct uds_record_name *name) +{ + return get_unaligned_be16(&name->name[SAMPLE_BYTES_OFFSET]); +} + +/* Compute the chapter delta list for a given name. */ +static inline u32 uds_hash_to_chapter_delta_list(const struct uds_record_name *name, + const struct index_geometry *geometry) +{ + return ((uds_extract_chapter_index_bytes(name) >> geometry->chapter_address_bits) & + ((1 << geometry->chapter_delta_list_bits) - 1)); +} + +/* Compute the chapter delta address for a given name. */ +static inline u32 uds_hash_to_chapter_delta_address(const struct uds_record_name *name, + const struct index_geometry *geometry) +{ + return uds_extract_chapter_index_bytes(name) & ((1 << geometry->chapter_address_bits) - 1); +} + +static inline unsigned int uds_name_to_hash_slot(const struct uds_record_name *name, + unsigned int slot_count) +{ + return (unsigned int) (uds_extract_chapter_index_bytes(name) % slot_count); +} + +#endif /* UDS_HASH_UTILS_H */ -- cgit v1.2.3