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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/md/persistent-data/dm-btree-internal.h | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/md/persistent-data/dm-btree-internal.h')
-rw-r--r-- | drivers/md/persistent-data/dm-btree-internal.h | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/md/persistent-data/dm-btree-internal.h b/drivers/md/persistent-data/dm-btree-internal.h new file mode 100644 index 000000000..5673f8eb5 --- /dev/null +++ b/drivers/md/persistent-data/dm-btree-internal.h @@ -0,0 +1,147 @@ +/* + * Copyright (C) 2011 Red Hat, Inc. + * + * This file is released under the GPL. + */ + +#ifndef DM_BTREE_INTERNAL_H +#define DM_BTREE_INTERNAL_H + +#include "dm-btree.h" + +/*----------------------------------------------------------------*/ + +/* + * We'll need 2 accessor functions for n->csum and n->blocknr + * to support dm-btree-spine.c in that case. + */ + +enum node_flags { + INTERNAL_NODE = 1, + LEAF_NODE = 1 << 1 +}; + +/* + * Every btree node begins with this structure. Make sure it's a multiple + * of 8-bytes in size, otherwise the 64bit keys will be mis-aligned. + */ +struct node_header { + __le32 csum; + __le32 flags; + __le64 blocknr; /* Block this node is supposed to live in. */ + + __le32 nr_entries; + __le32 max_entries; + __le32 value_size; + __le32 padding; +} __attribute__((packed, aligned(8))); + +struct btree_node { + struct node_header header; + __le64 keys[0]; +} __attribute__((packed, aligned(8))); + + +/* + * Locks a block using the btree node validator. + */ +int bn_read_lock(struct dm_btree_info *info, dm_block_t b, + struct dm_block **result); + +void inc_children(struct dm_transaction_manager *tm, struct btree_node *n, + struct dm_btree_value_type *vt); + +int new_block(struct dm_btree_info *info, struct dm_block **result); +void unlock_block(struct dm_btree_info *info, struct dm_block *b); + +/* + * Spines keep track of the rolling locks. There are 2 variants, read-only + * and one that uses shadowing. These are separate structs to allow the + * type checker to spot misuse, for example accidentally calling read_lock + * on a shadow spine. + */ +struct ro_spine { + struct dm_btree_info *info; + + int count; + struct dm_block *nodes[2]; +}; + +void init_ro_spine(struct ro_spine *s, struct dm_btree_info *info); +int exit_ro_spine(struct ro_spine *s); +int ro_step(struct ro_spine *s, dm_block_t new_child); +void ro_pop(struct ro_spine *s); +struct btree_node *ro_node(struct ro_spine *s); + +struct shadow_spine { + struct dm_btree_info *info; + + int count; + struct dm_block *nodes[2]; + + dm_block_t root; +}; + +void init_shadow_spine(struct shadow_spine *s, struct dm_btree_info *info); +int exit_shadow_spine(struct shadow_spine *s); + +int shadow_step(struct shadow_spine *s, dm_block_t b, + struct dm_btree_value_type *vt); + +/* + * The spine must have at least one entry before calling this. + */ +struct dm_block *shadow_current(struct shadow_spine *s); + +/* + * The spine must have at least two entries before calling this. + */ +struct dm_block *shadow_parent(struct shadow_spine *s); + +int shadow_has_parent(struct shadow_spine *s); + +int shadow_root(struct shadow_spine *s); + +/* + * Some inlines. + */ +static inline __le64 *key_ptr(struct btree_node *n, uint32_t index) +{ + return n->keys + index; +} + +static inline void *value_base(struct btree_node *n) +{ + return &n->keys[le32_to_cpu(n->header.max_entries)]; +} + +static inline void *value_ptr(struct btree_node *n, uint32_t index) +{ + uint32_t value_size = le32_to_cpu(n->header.value_size); + return value_base(n) + (value_size * index); +} + +/* + * Assumes the values are suitably-aligned and converts to core format. + */ +static inline uint64_t value64(struct btree_node *n, uint32_t index) +{ + __le64 *values_le = value_base(n); + + return le64_to_cpu(values_le[index]); +} + +/* + * Searching for a key within a single node. + */ +int lower_bound(struct btree_node *n, uint64_t key); + +extern struct dm_block_validator btree_node_validator; + +/* + * Value type for upper levels of multi-level btrees. + */ +extern void init_le64_type(struct dm_transaction_manager *tm, + struct dm_btree_value_type *vt); + +#endif /* DM_BTREE_INTERNAL_H */ |