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|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCACHEFS_H
#define _BCACHEFS_H
/*
* SOME HIGH LEVEL CODE DOCUMENTATION:
*
* Bcache mostly works with cache sets, cache devices, and backing devices.
*
* Support for multiple cache devices hasn't quite been finished off yet, but
* it's about 95% plumbed through. A cache set and its cache devices is sort of
* like a md raid array and its component devices. Most of the code doesn't care
* about individual cache devices, the main abstraction is the cache set.
*
* Multiple cache devices is intended to give us the ability to mirror dirty
* cached data and metadata, without mirroring clean cached data.
*
* Backing devices are different, in that they have a lifetime independent of a
* cache set. When you register a newly formatted backing device it'll come up
* in passthrough mode, and then you can attach and detach a backing device from
* a cache set at runtime - while it's mounted and in use. Detaching implicitly
* invalidates any cached data for that backing device.
*
* A cache set can have multiple (many) backing devices attached to it.
*
* There's also flash only volumes - this is the reason for the distinction
* between struct cached_dev and struct bcache_device. A flash only volume
* works much like a bcache device that has a backing device, except the
* "cached" data is always dirty. The end result is that we get thin
* provisioning with very little additional code.
*
* Flash only volumes work but they're not production ready because the moving
* garbage collector needs more work. More on that later.
*
* BUCKETS/ALLOCATION:
*
* Bcache is primarily designed for caching, which means that in normal
* operation all of our available space will be allocated. Thus, we need an
* efficient way of deleting things from the cache so we can write new things to
* it.
*
* To do this, we first divide the cache device up into buckets. A bucket is the
* unit of allocation; they're typically around 1 mb - anywhere from 128k to 2M+
* works efficiently.
*
* Each bucket has a 16 bit priority, and an 8 bit generation associated with
* it. The gens and priorities for all the buckets are stored contiguously and
* packed on disk (in a linked list of buckets - aside from the superblock, all
* of bcache's metadata is stored in buckets).
*
* The priority is used to implement an LRU. We reset a bucket's priority when
* we allocate it or on cache it, and every so often we decrement the priority
* of each bucket. It could be used to implement something more sophisticated,
* if anyone ever gets around to it.
*
* The generation is used for invalidating buckets. Each pointer also has an 8
* bit generation embedded in it; for a pointer to be considered valid, its gen
* must match the gen of the bucket it points into. Thus, to reuse a bucket all
* we have to do is increment its gen (and write its new gen to disk; we batch
* this up).
*
* Bcache is entirely COW - we never write twice to a bucket, even buckets that
* contain metadata (including btree nodes).
*
* THE BTREE:
*
* Bcache is in large part design around the btree.
*
* At a high level, the btree is just an index of key -> ptr tuples.
*
* Keys represent extents, and thus have a size field. Keys also have a variable
* number of pointers attached to them (potentially zero, which is handy for
* invalidating the cache).
*
* The key itself is an inode:offset pair. The inode number corresponds to a
* backing device or a flash only volume. The offset is the ending offset of the
* extent within the inode - not the starting offset; this makes lookups
* slightly more convenient.
*
* Pointers contain the cache device id, the offset on that device, and an 8 bit
* generation number. More on the gen later.
*
* Index lookups are not fully abstracted - cache lookups in particular are
* still somewhat mixed in with the btree code, but things are headed in that
* direction.
*
* Updates are fairly well abstracted, though. There are two different ways of
* updating the btree; insert and replace.
*
* BTREE_INSERT will just take a list of keys and insert them into the btree -
* overwriting (possibly only partially) any extents they overlap with. This is
* used to update the index after a write.
*
* BTREE_REPLACE is really cmpxchg(); it inserts a key into the btree iff it is
* overwriting a key that matches another given key. This is used for inserting
* data into the cache after a cache miss, and for background writeback, and for
* the moving garbage collector.
*
* There is no "delete" operation; deleting things from the index is
* accomplished by either by invalidating pointers (by incrementing a bucket's
* gen) or by inserting a key with 0 pointers - which will overwrite anything
* previously present at that location in the index.
*
* This means that there are always stale/invalid keys in the btree. They're
* filtered out by the code that iterates through a btree node, and removed when
* a btree node is rewritten.
*
* BTREE NODES:
*
* Our unit of allocation is a bucket, and we we can't arbitrarily allocate and
* free smaller than a bucket - so, that's how big our btree nodes are.
*
* (If buckets are really big we'll only use part of the bucket for a btree node
* - no less than 1/4th - but a bucket still contains no more than a single
* btree node. I'd actually like to change this, but for now we rely on the
* bucket's gen for deleting btree nodes when we rewrite/split a node.)
*
* Anyways, btree nodes are big - big enough to be inefficient with a textbook
* btree implementation.
*
* The way this is solved is that btree nodes are internally log structured; we
* can append new keys to an existing btree node without rewriting it. This
* means each set of keys we write is sorted, but the node is not.
*
* We maintain this log structure in memory - keeping 1Mb of keys sorted would
* be expensive, and we have to distinguish between the keys we have written and
* the keys we haven't. So to do a lookup in a btree node, we have to search
* each sorted set. But we do merge written sets together lazily, so the cost of
* these extra searches is quite low (normally most of the keys in a btree node
* will be in one big set, and then there'll be one or two sets that are much
* smaller).
*
* This log structure makes bcache's btree more of a hybrid between a
* conventional btree and a compacting data structure, with some of the
* advantages of both.
*
* GARBAGE COLLECTION:
*
* We can't just invalidate any bucket - it might contain dirty data or
* metadata. If it once contained dirty data, other writes might overwrite it
* later, leaving no valid pointers into that bucket in the index.
*
* Thus, the primary purpose of garbage collection is to find buckets to reuse.
* It also counts how much valid data it each bucket currently contains, so that
* allocation can reuse buckets sooner when they've been mostly overwritten.
*
* It also does some things that are really internal to the btree
* implementation. If a btree node contains pointers that are stale by more than
* some threshold, it rewrites the btree node to avoid the bucket's generation
* wrapping around. It also merges adjacent btree nodes if they're empty enough.
*
* THE JOURNAL:
*
* Bcache's journal is not necessary for consistency; we always strictly
* order metadata writes so that the btree and everything else is consistent on
* disk in the event of an unclean shutdown, and in fact bcache had writeback
* caching (with recovery from unclean shutdown) before journalling was
* implemented.
*
* Rather, the journal is purely a performance optimization; we can't complete a
* write until we've updated the index on disk, otherwise the cache would be
* inconsistent in the event of an unclean shutdown. This means that without the
* journal, on random write workloads we constantly have to update all the leaf
* nodes in the btree, and those writes will be mostly empty (appending at most
* a few keys each) - highly inefficient in terms of amount of metadata writes,
* and it puts more strain on the various btree resorting/compacting code.
*
* The journal is just a log of keys we've inserted; on startup we just reinsert
* all the keys in the open journal entries. That means that when we're updating
* a node in the btree, we can wait until a 4k block of keys fills up before
* writing them out.
*
* For simplicity, we only journal updates to leaf nodes; updates to parent
* nodes are rare enough (since our leaf nodes are huge) that it wasn't worth
* the complexity to deal with journalling them (in particular, journal replay)
* - updates to non leaf nodes just happen synchronously (see btree_split()).
*/
#undef pr_fmt
#define pr_fmt(fmt) "bcachefs: %s() " fmt "\n", __func__
#include <linux/backing-dev-defs.h>
#include <linux/bug.h>
#include <linux/bio.h>
#include <linux/closure.h>
#include <linux/kobject.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/percpu-refcount.h>
#include <linux/percpu-rwsem.h>
#include <linux/rhashtable.h>
#include <linux/rwsem.h>
#include <linux/seqlock.h>
#include <linux/shrinker.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <linux/zstd.h>
#include "bcachefs_format.h"
#include "fifo.h"
#include "opts.h"
#include "util.h"
#define dynamic_fault(...) 0
#define race_fault(...) 0
#define bch2_fs_init_fault(name) \
dynamic_fault("bcachefs:bch_fs_init:" name)
#define bch2_meta_read_fault(name) \
dynamic_fault("bcachefs:meta:read:" name)
#define bch2_meta_write_fault(name) \
dynamic_fault("bcachefs:meta:write:" name)
#ifdef __KERNEL__
#define bch2_fmt(_c, fmt) "bcachefs (%s): " fmt "\n", ((_c)->name)
#else
#define bch2_fmt(_c, fmt) fmt "\n"
#endif
#define bch_info(c, fmt, ...) \
printk(KERN_INFO bch2_fmt(c, fmt), ##__VA_ARGS__)
#define bch_notice(c, fmt, ...) \
printk(KERN_NOTICE bch2_fmt(c, fmt), ##__VA_ARGS__)
#define bch_warn(c, fmt, ...) \
printk(KERN_WARNING bch2_fmt(c, fmt), ##__VA_ARGS__)
#define bch_err(c, fmt, ...) \
printk(KERN_ERR bch2_fmt(c, fmt), ##__VA_ARGS__)
#define bch_err_ratelimited(c, fmt, ...) \
printk_ratelimited(KERN_ERR bch2_fmt(c, fmt), ##__VA_ARGS__)
#define bch_verbose(c, fmt, ...) \
do { \
if ((c)->opts.verbose) \
bch_info(c, fmt, ##__VA_ARGS__); \
} while (0)
#define pr_verbose_init(opts, fmt, ...) \
do { \
if (opt_get(opts, verbose)) \
pr_info(fmt, ##__VA_ARGS__); \
} while (0)
/* Parameters that are useful for debugging, but should always be compiled in: */
#define BCH_DEBUG_PARAMS_ALWAYS() \
BCH_DEBUG_PARAM(key_merging_disabled, \
"Disables merging of extents") \
BCH_DEBUG_PARAM(btree_gc_always_rewrite, \
"Causes mark and sweep to compact and rewrite every " \
"btree node it traverses") \
BCH_DEBUG_PARAM(btree_gc_rewrite_disabled, \
"Disables rewriting of btree nodes during mark and sweep")\
BCH_DEBUG_PARAM(btree_shrinker_disabled, \
"Disables the shrinker callback for the btree node cache")
/* Parameters that should only be compiled in in debug mode: */
#define BCH_DEBUG_PARAMS_DEBUG() \
BCH_DEBUG_PARAM(expensive_debug_checks, \
"Enables various runtime debugging checks that " \
"significantly affect performance") \
BCH_DEBUG_PARAM(debug_check_bkeys, \
"Run bkey_debugcheck (primarily checking GC/allocation "\
"information) when iterating over keys") \
BCH_DEBUG_PARAM(verify_btree_ondisk, \
"Reread btree nodes at various points to verify the " \
"mergesort in the read path against modifications " \
"done in memory") \
BCH_DEBUG_PARAM(journal_seq_verify, \
"Store the journal sequence number in the version " \
"number of every btree key, and verify that btree " \
"update ordering is preserved during recovery") \
BCH_DEBUG_PARAM(inject_invalid_keys, \
"Store the journal sequence number in the version " \
"number of every btree key, and verify that btree " \
"update ordering is preserved during recovery") \
BCH_DEBUG_PARAM(test_alloc_startup, \
"Force allocator startup to use the slowpath where it" \
"can't find enough free buckets without invalidating" \
"cached data") \
BCH_DEBUG_PARAM(force_reconstruct_read, \
"Force reads to use the reconstruct path, when reading" \
"from erasure coded extents")
#define BCH_DEBUG_PARAMS_ALL() BCH_DEBUG_PARAMS_ALWAYS() BCH_DEBUG_PARAMS_DEBUG()
#ifdef CONFIG_BCACHEFS_DEBUG
#define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALL()
#else
#define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALWAYS()
#endif
#define BCH_TIME_STATS() \
x(btree_node_mem_alloc) \
x(btree_gc) \
x(btree_split) \
x(btree_sort) \
x(btree_read) \
x(btree_lock_contended_read) \
x(btree_lock_contended_intent) \
x(btree_lock_contended_write) \
x(data_write) \
x(data_read) \
x(data_promote) \
x(journal_write) \
x(journal_delay) \
x(journal_blocked) \
x(journal_flush_seq)
enum bch_time_stats {
#define x(name) BCH_TIME_##name,
BCH_TIME_STATS()
#undef x
BCH_TIME_STAT_NR
};
#include "alloc_types.h"
#include "btree_types.h"
#include "buckets_types.h"
#include "clock_types.h"
#include "ec_types.h"
#include "journal_types.h"
#include "keylist_types.h"
#include "quota_types.h"
#include "rebalance_types.h"
#include "replicas_types.h"
#include "super_types.h"
/* Number of nodes btree coalesce will try to coalesce at once */
#define GC_MERGE_NODES 4U
/* Maximum number of nodes we might need to allocate atomically: */
#define BTREE_RESERVE_MAX (BTREE_MAX_DEPTH + (BTREE_MAX_DEPTH - 1))
/* Size of the freelist we allocate btree nodes from: */
#define BTREE_NODE_RESERVE BTREE_RESERVE_MAX
#define BTREE_NODE_OPEN_BUCKET_RESERVE (BTREE_RESERVE_MAX * BCH_REPLICAS_MAX)
struct btree;
enum gc_phase {
GC_PHASE_NOT_RUNNING,
GC_PHASE_START,
GC_PHASE_SB,
GC_PHASE_BTREE_EC,
GC_PHASE_BTREE_EXTENTS,
GC_PHASE_BTREE_INODES,
GC_PHASE_BTREE_DIRENTS,
GC_PHASE_BTREE_XATTRS,
GC_PHASE_BTREE_ALLOC,
GC_PHASE_BTREE_QUOTAS,
GC_PHASE_PENDING_DELETE,
GC_PHASE_ALLOC,
};
struct gc_pos {
enum gc_phase phase;
struct bpos pos;
unsigned level;
};
struct io_count {
u64 sectors[2][BCH_DATA_NR];
};
struct bch_dev {
struct kobject kobj;
struct percpu_ref ref;
struct completion ref_completion;
struct percpu_ref io_ref;
struct completion io_ref_completion;
struct bch_fs *fs;
u8 dev_idx;
/*
* Cached version of this device's member info from superblock
* Committed by bch2_write_super() -> bch_fs_mi_update()
*/
struct bch_member_cpu mi;
__uuid_t uuid;
char name[BDEVNAME_SIZE];
struct bch_sb_handle disk_sb;
int sb_write_error;
struct bch_devs_mask self;
/* biosets used in cloned bios for writing multiple replicas */
struct bio_set replica_set;
/*
* Buckets:
* Per-bucket arrays are protected by c->mark_lock, bucket_lock and
* gc_lock, for device resize - holding any is sufficient for access:
* Or rcu_read_lock(), but only for ptr_stale():
*/
struct bucket_array __rcu *buckets[2];
unsigned long *buckets_nouse;
unsigned long *buckets_written;
/* most out of date gen in the btree */
u8 *oldest_gens;
struct rw_semaphore bucket_lock;
struct bch_dev_usage __percpu *usage[2];
/* Allocator: */
struct task_struct __rcu *alloc_thread;
/*
* free: Buckets that are ready to be used
*
* free_inc: Incoming buckets - these are buckets that currently have
* cached data in them, and we can't reuse them until after we write
* their new gen to disk. After prio_write() finishes writing the new
* gens/prios, they'll be moved to the free list (and possibly discarded
* in the process)
*/
alloc_fifo free[RESERVE_NR];
alloc_fifo free_inc;
spinlock_t freelist_lock;
u8 open_buckets_partial[OPEN_BUCKETS_COUNT];
unsigned open_buckets_partial_nr;
size_t fifo_last_bucket;
/* last calculated minimum prio */
u16 max_last_bucket_io[2];
size_t inc_gen_needs_gc;
size_t inc_gen_really_needs_gc;
bool allocator_blocked;
alloc_heap alloc_heap;
/* Copying GC: */
struct task_struct *copygc_thread;
copygc_heap copygc_heap;
struct bch_pd_controller copygc_pd;
struct write_point copygc_write_point;
u64 copygc_threshold;
atomic64_t rebalance_work;
struct journal_device journal;
struct work_struct io_error_work;
/* The rest of this all shows up in sysfs */
atomic64_t cur_latency[2];
struct bch2_time_stats io_latency[2];
#define CONGESTED_MAX 1024
atomic_t congested;
u64 congested_last;
struct io_count __percpu *io_done;
};
/*
* Flag bits for what phase of startup/shutdown the cache set is at, how we're
* shutting down, etc.:
*
* BCH_FS_UNREGISTERING means we're not just shutting down, we're detaching
* all the backing devices first (their cached data gets invalidated, and they
* won't automatically reattach).
*/
enum {
/* startup: */
BCH_FS_ALLOC_READ_DONE,
BCH_FS_ALLOCATOR_STARTED,
BCH_FS_INITIAL_GC_DONE,
BCH_FS_FSCK_DONE,
BCH_FS_STARTED,
/* shutdown: */
BCH_FS_EMERGENCY_RO,
BCH_FS_WRITE_DISABLE_COMPLETE,
/* errors: */
BCH_FS_ERROR,
/* misc: */
BCH_FS_BDEV_MOUNTED,
BCH_FS_FSCK_FIXED_ERRORS,
BCH_FS_FSCK_UNFIXED_ERRORS,
BCH_FS_FIXED_GENS,
BCH_FS_REBUILD_REPLICAS,
BCH_FS_HOLD_BTREE_WRITES,
};
struct btree_debug {
unsigned id;
struct dentry *btree;
struct dentry *btree_format;
struct dentry *failed;
};
enum bch_fs_state {
BCH_FS_STARTING = 0,
BCH_FS_STOPPING,
BCH_FS_RO,
BCH_FS_RW,
};
struct bch_fs_pcpu {
u64 sectors_available;
};
struct bch_fs {
struct closure cl;
struct list_head list;
struct kobject kobj;
struct kobject internal;
struct kobject opts_dir;
struct kobject time_stats;
unsigned long flags;
int minor;
struct device *chardev;
struct super_block *vfs_sb;
char name[40];
/* ro/rw, add/remove devices: */
struct mutex state_lock;
enum bch_fs_state state;
/* Counts outstanding writes, for clean transition to read-only */
struct percpu_ref writes;
struct work_struct read_only_work;
struct bch_dev __rcu *devs[BCH_SB_MEMBERS_MAX];
struct bch_replicas_cpu replicas;
struct bch_replicas_cpu replicas_gc;
struct mutex replicas_gc_lock;
struct bch_disk_groups_cpu __rcu *disk_groups;
struct bch_opts opts;
/* Updated by bch2_sb_update():*/
struct {
__uuid_t uuid;
__uuid_t user_uuid;
u16 version;
u16 encoded_extent_max;
u8 nr_devices;
u8 clean;
u8 encryption_type;
u64 time_base_lo;
u32 time_base_hi;
u32 time_precision;
u64 features;
} sb;
struct bch_sb_handle disk_sb;
unsigned short block_bits; /* ilog2(block_size) */
u16 btree_foreground_merge_threshold;
struct closure sb_write;
struct mutex sb_lock;
/* BTREE CACHE */
struct bio_set btree_bio;
struct btree_root btree_roots[BTREE_ID_NR];
bool btree_roots_dirty;
struct mutex btree_root_lock;
struct btree_cache btree_cache;
mempool_t btree_reserve_pool;
/*
* Cache of allocated btree nodes - if we allocate a btree node and
* don't use it, if we free it that space can't be reused until going
* _all_ the way through the allocator (which exposes us to a livelock
* when allocating btree reserves fail halfway through) - instead, we
* can stick them here:
*/
struct btree_alloc btree_reserve_cache[BTREE_NODE_RESERVE * 2];
unsigned btree_reserve_cache_nr;
struct mutex btree_reserve_cache_lock;
mempool_t btree_interior_update_pool;
struct list_head btree_interior_update_list;
struct mutex btree_interior_update_lock;
struct closure_waitlist btree_interior_update_wait;
mempool_t btree_iters_pool;
struct workqueue_struct *wq;
/* copygc needs its own workqueue for index updates.. */
struct workqueue_struct *copygc_wq;
struct workqueue_struct *journal_reclaim_wq;
/* ALLOCATION */
struct delayed_work pd_controllers_update;
unsigned pd_controllers_update_seconds;
struct bch_devs_mask rw_devs[BCH_DATA_NR];
u64 capacity; /* sectors */
/*
* When capacity _decreases_ (due to a disk being removed), we
* increment capacity_gen - this invalidates outstanding reservations
* and forces them to be revalidated
*/
u32 capacity_gen;
unsigned bucket_size_max;
atomic64_t sectors_available;
struct bch_fs_pcpu __percpu *pcpu;
struct percpu_rw_semaphore mark_lock;
struct bch_fs_usage __percpu *usage[2];
struct bch_fs_usage __percpu *usage_scratch;
/*
* When we invalidate buckets, we use both the priority and the amount
* of good data to determine which buckets to reuse first - to weight
* those together consistently we keep track of the smallest nonzero
* priority of any bucket.
*/
struct bucket_clock bucket_clock[2];
struct io_clock io_clock[2];
/* ALLOCATOR */
spinlock_t freelist_lock;
struct closure_waitlist freelist_wait;
u8 open_buckets_freelist;
u8 open_buckets_nr_free;
struct closure_waitlist open_buckets_wait;
struct open_bucket open_buckets[OPEN_BUCKETS_COUNT];
struct write_point btree_write_point;
struct write_point rebalance_write_point;
struct write_point write_points[WRITE_POINT_MAX];
struct hlist_head write_points_hash[WRITE_POINT_HASH_NR];
struct mutex write_points_hash_lock;
unsigned write_points_nr;
/* GARBAGE COLLECTION */
struct task_struct *gc_thread;
atomic_t kick_gc;
unsigned long gc_count;
/*
* Tracks GC's progress - everything in the range [ZERO_KEY..gc_cur_pos]
* has been marked by GC.
*
* gc_cur_phase is a superset of btree_ids (BTREE_ID_EXTENTS etc.)
*
* Protected by gc_pos_lock. Only written to by GC thread, so GC thread
* can read without a lock.
*/
seqcount_t gc_pos_lock;
struct gc_pos gc_pos;
/*
* The allocation code needs gc_mark in struct bucket to be correct, but
* it's not while a gc is in progress.
*/
struct rw_semaphore gc_lock;
/* IO PATH */
struct bio_set bio_read;
struct bio_set bio_read_split;
struct bio_set bio_write;
struct mutex bio_bounce_pages_lock;
mempool_t bio_bounce_pages;
struct rhashtable promote_table;
mempool_t compression_bounce[2];
mempool_t compress_workspace[BCH_COMPRESSION_NR];
mempool_t decompress_workspace;
ZSTD_parameters zstd_params;
struct crypto_shash *sha256;
struct crypto_sync_skcipher *chacha20;
struct crypto_shash *poly1305;
atomic64_t key_version;
/* REBALANCE */
struct bch_fs_rebalance rebalance;
/* STRIPES: */
GENRADIX(struct stripe) stripes[2];
struct mutex ec_stripe_create_lock;
ec_stripes_heap ec_stripes_heap;
spinlock_t ec_stripes_heap_lock;
/* ERASURE CODING */
struct list_head ec_new_stripe_list;
struct mutex ec_new_stripe_lock;
struct bio_set ec_bioset;
struct work_struct ec_stripe_delete_work;
struct llist_head ec_stripe_delete_list;
/* VFS IO PATH - fs-io.c */
struct bio_set writepage_bioset;
struct bio_set dio_write_bioset;
struct bio_set dio_read_bioset;
struct bio_list btree_write_error_list;
struct work_struct btree_write_error_work;
spinlock_t btree_write_error_lock;
/* ERRORS */
struct list_head fsck_errors;
struct mutex fsck_error_lock;
bool fsck_alloc_err;
/* QUOTAS */
struct bch_memquota_type quotas[QTYP_NR];
/* DEBUG JUNK */
struct dentry *debug;
struct btree_debug btree_debug[BTREE_ID_NR];
#ifdef CONFIG_BCACHEFS_DEBUG
struct btree *verify_data;
struct btree_node *verify_ondisk;
struct mutex verify_lock;
#endif
u64 unused_inode_hint;
/*
* A btree node on disk could have too many bsets for an iterator to fit
* on the stack - have to dynamically allocate them
*/
mempool_t fill_iter;
mempool_t btree_bounce_pool;
struct journal journal;
u64 last_bucket_seq_cleanup;
/* The rest of this all shows up in sysfs */
atomic_long_t read_realloc_races;
atomic_long_t extent_migrate_done;
atomic_long_t extent_migrate_raced;
unsigned btree_gc_periodic:1;
unsigned copy_gc_enabled:1;
bool promote_whole_extents;
#define BCH_DEBUG_PARAM(name, description) bool name;
BCH_DEBUG_PARAMS_ALL()
#undef BCH_DEBUG_PARAM
struct bch2_time_stats times[BCH_TIME_STAT_NR];
};
static inline void bch2_set_ra_pages(struct bch_fs *c, unsigned ra_pages)
{
#ifndef NO_BCACHEFS_FS
if (c->vfs_sb)
c->vfs_sb->s_bdi->ra_pages = ra_pages;
#endif
}
static inline bool bch2_fs_running(struct bch_fs *c)
{
return c->state == BCH_FS_RO || c->state == BCH_FS_RW;
}
static inline unsigned bucket_bytes(const struct bch_dev *ca)
{
return ca->mi.bucket_size << 9;
}
static inline unsigned block_bytes(const struct bch_fs *c)
{
return c->opts.block_size << 9;
}
static inline struct timespec64 bch2_time_to_timespec(struct bch_fs *c, u64 time)
{
return ns_to_timespec64(time * c->sb.time_precision + c->sb.time_base_lo);
}
static inline s64 timespec_to_bch2_time(struct bch_fs *c, struct timespec64 ts)
{
s64 ns = timespec64_to_ns(&ts) - c->sb.time_base_lo;
if (c->sb.time_precision == 1)
return ns;
return div_s64(ns, c->sb.time_precision);
}
static inline s64 bch2_current_time(struct bch_fs *c)
{
struct timespec64 now;
ktime_get_real_ts64(&now);
return timespec_to_bch2_time(c, now);
}
#endif /* _BCACHEFS_H */
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