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linuxdebug/fs/ext4/extents_status.h

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// SPDX-License-Identifier: GPL-2.0
/*
* fs/ext4/extents_status.h
*
* Written by Yongqiang Yang <xiaoqiangnk@gmail.com>
* Modified by
* Allison Henderson <achender@linux.vnet.ibm.com>
* Zheng Liu <wenqing.lz@taobao.com>
*
*/
#ifndef _EXT4_EXTENTS_STATUS_H
#define _EXT4_EXTENTS_STATUS_H
/*
* Turn on ES_DEBUG__ to get lots of info about extent status operations.
*/
#ifdef ES_DEBUG__
#define es_debug(fmt, ...) printk(fmt, ##__VA_ARGS__)
#else
#define es_debug(fmt, ...) no_printk(fmt, ##__VA_ARGS__)
#endif
/*
* With ES_AGGRESSIVE_TEST defined, the result of es caching will be
* checked with old map_block's result.
*/
#define ES_AGGRESSIVE_TEST__
/*
* These flags live in the high bits of extent_status.es_pblk
*/
enum {
ES_WRITTEN_B,
ES_UNWRITTEN_B,
ES_DELAYED_B,
ES_HOLE_B,
ES_REFERENCED_B,
ES_FLAGS
};
#define ES_SHIFT (sizeof(ext4_fsblk_t)*8 - ES_FLAGS)
#define ES_MASK (~((ext4_fsblk_t)0) << ES_SHIFT)
#define EXTENT_STATUS_WRITTEN (1 << ES_WRITTEN_B)
#define EXTENT_STATUS_UNWRITTEN (1 << ES_UNWRITTEN_B)
#define EXTENT_STATUS_DELAYED (1 << ES_DELAYED_B)
#define EXTENT_STATUS_HOLE (1 << ES_HOLE_B)
#define EXTENT_STATUS_REFERENCED (1 << ES_REFERENCED_B)
#define ES_TYPE_MASK ((ext4_fsblk_t)(EXTENT_STATUS_WRITTEN | \
EXTENT_STATUS_UNWRITTEN | \
EXTENT_STATUS_DELAYED | \
EXTENT_STATUS_HOLE) << ES_SHIFT)
struct ext4_sb_info;
struct ext4_extent;
struct extent_status {
struct rb_node rb_node;
ext4_lblk_t es_lblk; /* first logical block extent covers */
ext4_lblk_t es_len; /* length of extent in block */
ext4_fsblk_t es_pblk; /* first physical block */
};
struct ext4_es_tree {
struct rb_root root;
struct extent_status *cache_es; /* recently accessed extent */
};
struct ext4_es_stats {
unsigned long es_stats_shrunk;
struct percpu_counter es_stats_cache_hits;
struct percpu_counter es_stats_cache_misses;
u64 es_stats_scan_time;
u64 es_stats_max_scan_time;
struct percpu_counter es_stats_all_cnt;
struct percpu_counter es_stats_shk_cnt;
};
/*
* Pending cluster reservations for bigalloc file systems
*
* A cluster with a pending reservation is a logical cluster shared by at
* least one extent in the extents status tree with delayed and unwritten
* status and at least one other written or unwritten extent. The
* reservation is said to be pending because a cluster reservation would
* have to be taken in the event all blocks in the cluster shared with
* written or unwritten extents were deleted while the delayed and
* unwritten blocks remained.
*
* The set of pending cluster reservations is an auxiliary data structure
* used with the extents status tree to implement reserved cluster/block
* accounting for bigalloc file systems. The set is kept in memory and
* records all pending cluster reservations.
*
* Its primary function is to avoid the need to read extents from the
* disk when invalidating pages as a result of a truncate, punch hole, or
* collapse range operation. Page invalidation requires a decrease in the
* reserved cluster count if it results in the removal of all delayed
* and unwritten extents (blocks) from a cluster that is not shared with a
* written or unwritten extent, and no decrease otherwise. Determining
* whether the cluster is shared can be done by searching for a pending
* reservation on it.
*
* Secondarily, it provides a potentially faster method for determining
* whether the reserved cluster count should be increased when a physical
* cluster is deallocated as a result of a truncate, punch hole, or
* collapse range operation. The necessary information is also present
* in the extents status tree, but might be more rapidly accessed in
* the pending reservation set in many cases due to smaller size.
*
* The pending cluster reservation set is implemented as a red-black tree
* with the goal of minimizing per page search time overhead.
*/
struct pending_reservation {
struct rb_node rb_node;
ext4_lblk_t lclu;
};
struct ext4_pending_tree {
struct rb_root root;
};
extern int __init ext4_init_es(void);
extern void ext4_exit_es(void);
extern void ext4_es_init_tree(struct ext4_es_tree *tree);
extern int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t len, ext4_fsblk_t pblk,
unsigned int status);
extern void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t len, ext4_fsblk_t pblk,
unsigned int status);
extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t len);
extern void ext4_es_find_extent_range(struct inode *inode,
int (*match_fn)(struct extent_status *es),
ext4_lblk_t lblk, ext4_lblk_t end,
struct extent_status *es);
extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t *next_lblk,
struct extent_status *es);
extern bool ext4_es_scan_range(struct inode *inode,
int (*matching_fn)(struct extent_status *es),
ext4_lblk_t lblk, ext4_lblk_t end);
extern bool ext4_es_scan_clu(struct inode *inode,
int (*matching_fn)(struct extent_status *es),
ext4_lblk_t lblk);
static inline unsigned int ext4_es_status(struct extent_status *es)
{
return es->es_pblk >> ES_SHIFT;
}
static inline unsigned int ext4_es_type(struct extent_status *es)
{
return (es->es_pblk & ES_TYPE_MASK) >> ES_SHIFT;
}
static inline int ext4_es_is_written(struct extent_status *es)
{
return (ext4_es_type(es) & EXTENT_STATUS_WRITTEN) != 0;
}
static inline int ext4_es_is_unwritten(struct extent_status *es)
{
return (ext4_es_type(es) & EXTENT_STATUS_UNWRITTEN) != 0;
}
static inline int ext4_es_is_delayed(struct extent_status *es)
{
return (ext4_es_type(es) & EXTENT_STATUS_DELAYED) != 0;
}
static inline int ext4_es_is_hole(struct extent_status *es)
{
return (ext4_es_type(es) & EXTENT_STATUS_HOLE) != 0;
}
static inline int ext4_es_is_mapped(struct extent_status *es)
{
return (ext4_es_is_written(es) || ext4_es_is_unwritten(es));
}
static inline int ext4_es_is_delonly(struct extent_status *es)
{
return (ext4_es_is_delayed(es) && !ext4_es_is_unwritten(es));
}
static inline void ext4_es_set_referenced(struct extent_status *es)
{
es->es_pblk |= ((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT;
}
static inline void ext4_es_clear_referenced(struct extent_status *es)
{
es->es_pblk &= ~(((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT);
}
static inline int ext4_es_is_referenced(struct extent_status *es)
{
return (ext4_es_status(es) & EXTENT_STATUS_REFERENCED) != 0;
}
static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
{
return es->es_pblk & ~ES_MASK;
}
static inline ext4_fsblk_t ext4_es_show_pblock(struct extent_status *es)
{
ext4_fsblk_t pblock = ext4_es_pblock(es);
return pblock == ~ES_MASK ? 0 : pblock;
}
static inline void ext4_es_store_pblock(struct extent_status *es,
ext4_fsblk_t pb)
{
ext4_fsblk_t block;
block = (pb & ~ES_MASK) | (es->es_pblk & ES_MASK);
es->es_pblk = block;
}
static inline void ext4_es_store_status(struct extent_status *es,
unsigned int status)
{
es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
(es->es_pblk & ~ES_MASK);
}
static inline void ext4_es_store_pblock_status(struct extent_status *es,
ext4_fsblk_t pb,
unsigned int status)
{
es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) |
(pb & ~ES_MASK);
}
extern int ext4_es_register_shrinker(struct ext4_sb_info *sbi);
extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi);
extern int ext4_seq_es_shrinker_info_show(struct seq_file *seq, void *v);
extern int __init ext4_init_pending(void);
extern void ext4_exit_pending(void);
extern void ext4_init_pending_tree(struct ext4_pending_tree *tree);
extern void ext4_remove_pending(struct inode *inode, ext4_lblk_t lblk);
extern bool ext4_is_pending(struct inode *inode, ext4_lblk_t lblk);
extern int ext4_es_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk,
bool allocated);
extern unsigned int ext4_es_delayed_clu(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t len);
extern void ext4_clear_inode_es(struct inode *inode);
#endif /* _EXT4_EXTENTS_STATUS_H */
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