cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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extent_map.h (3019B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2
      3#ifndef BTRFS_EXTENT_MAP_H
      4#define BTRFS_EXTENT_MAP_H
      5
      6#include <linux/rbtree.h>
      7#include <linux/refcount.h>
      8
      9#define EXTENT_MAP_LAST_BYTE ((u64)-4)
     10#define EXTENT_MAP_HOLE ((u64)-3)
     11#define EXTENT_MAP_INLINE ((u64)-2)
     12/* used only during fiemap calls */
     13#define EXTENT_MAP_DELALLOC ((u64)-1)
     14
     15/* bits for the extent_map::flags field */
     16enum {
     17	/* this entry not yet on disk, don't free it */
     18	EXTENT_FLAG_PINNED,
     19	EXTENT_FLAG_COMPRESSED,
     20	/* pre-allocated extent */
     21	EXTENT_FLAG_PREALLOC,
     22	/* Logging this extent */
     23	EXTENT_FLAG_LOGGING,
     24	/* Filling in a preallocated extent */
     25	EXTENT_FLAG_FILLING,
     26	/* filesystem extent mapping type */
     27	EXTENT_FLAG_FS_MAPPING,
     28	/* This em is merged from two or more physically adjacent ems */
     29	EXTENT_FLAG_MERGED,
     30};
     31
     32struct extent_map {
     33	struct rb_node rb_node;
     34
     35	/* all of these are in bytes */
     36	u64 start;
     37	u64 len;
     38	u64 mod_start;
     39	u64 mod_len;
     40	u64 orig_start;
     41	u64 orig_block_len;
     42	u64 ram_bytes;
     43	u64 block_start;
     44	u64 block_len;
     45
     46	/*
     47	 * Generation of the extent map, for merged em it's the highest
     48	 * generation of all merged ems.
     49	 * For non-merged extents, it's from btrfs_file_extent_item::generation.
     50	 */
     51	u64 generation;
     52	unsigned long flags;
     53	/* Used for chunk mappings, flag EXTENT_FLAG_FS_MAPPING must be set */
     54	struct map_lookup *map_lookup;
     55	refcount_t refs;
     56	unsigned int compress_type;
     57	struct list_head list;
     58};
     59
     60struct extent_map_tree {
     61	struct rb_root_cached map;
     62	struct list_head modified_extents;
     63	rwlock_t lock;
     64};
     65
     66static inline int extent_map_in_tree(const struct extent_map *em)
     67{
     68	return !RB_EMPTY_NODE(&em->rb_node);
     69}
     70
     71static inline u64 extent_map_end(struct extent_map *em)
     72{
     73	if (em->start + em->len < em->start)
     74		return (u64)-1;
     75	return em->start + em->len;
     76}
     77
     78static inline u64 extent_map_block_end(struct extent_map *em)
     79{
     80	if (em->block_start + em->block_len < em->block_start)
     81		return (u64)-1;
     82	return em->block_start + em->block_len;
     83}
     84
     85void extent_map_tree_init(struct extent_map_tree *tree);
     86struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
     87					 u64 start, u64 len);
     88int add_extent_mapping(struct extent_map_tree *tree,
     89		       struct extent_map *em, int modified);
     90void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
     91void replace_extent_mapping(struct extent_map_tree *tree,
     92			    struct extent_map *cur,
     93			    struct extent_map *new,
     94			    int modified);
     95
     96struct extent_map *alloc_extent_map(void);
     97void free_extent_map(struct extent_map *em);
     98int __init extent_map_init(void);
     99void __cold extent_map_exit(void);
    100int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
    101void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
    102struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
    103					 u64 start, u64 len);
    104int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info,
    105			     struct extent_map_tree *em_tree,
    106			     struct extent_map **em_in, u64 start, u64 len);
    107
    108#endif