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Diffstat (limited to 'libbcache/bcache.h')
| -rw-r--r-- | libbcache/bcache.h | 831 |
1 files changed, 0 insertions, 831 deletions
diff --git a/libbcache/bcache.h b/libbcache/bcache.h deleted file mode 100644 index 1d0e998c..00000000 --- a/libbcache/bcache.h +++ /dev/null @@ -1,831 +0,0 @@ -#ifndef _BCACHE_H -#define _BCACHE_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) "bcache: %s() " fmt "\n", __func__ - -#include <linux/bug.h> -#include <linux/bcache.h> -#include <linux/bio.h> -#include <linux/kobject.h> -#include <linux/lglock.h> -#include <linux/list.h> -#include <linux/mutex.h> -#include <linux/percpu-refcount.h> -#include <linux/radix-tree.h> -#include <linux/rbtree.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 "bset.h" -#include "fifo.h" -#include "util.h" -#include "closure.h" -#include "opts.h" - -#include <linux/dynamic_fault.h> - -#define bch_fs_init_fault(name) \ - dynamic_fault("bcache:bch_fs_init:" name) -#define bch_meta_read_fault(name) \ - dynamic_fault("bcache:meta:read:" name) -#define bch_meta_write_fault(name) \ - dynamic_fault("bcache:meta:write:" name) - -#ifndef bch_fmt -#define bch_fmt(_c, fmt) "bcache (%s): " fmt "\n", ((_c)->name) -#endif - -#define bch_info(c, fmt, ...) \ - printk(KERN_INFO bch_fmt(c, fmt), ##__VA_ARGS__) -#define bch_notice(c, fmt, ...) \ - printk(KERN_NOTICE bch_fmt(c, fmt), ##__VA_ARGS__) -#define bch_warn(c, fmt, ...) \ - printk(KERN_WARNING bch_fmt(c, fmt), ##__VA_ARGS__) -#define bch_err(c, fmt, ...) \ - printk(KERN_ERR bch_fmt(c, fmt), ##__VA_ARGS__) - -#define bch_verbose(c, fmt, ...) \ -do { \ - if ((c)->opts.verbose_recovery) \ - bch_info(c, 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_gc_coalesce_disabled, \ - "Disables coalescing of btree nodes") \ - 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(version_stress_test, \ - "Assigns random version numbers to newly written " \ - "extents, to test overlapping extent cases") \ - 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") \ - -#define BCH_DEBUG_PARAMS_ALL() BCH_DEBUG_PARAMS_ALWAYS() BCH_DEBUG_PARAMS_DEBUG() - -#ifdef CONFIG_BCACHE_DEBUG -#define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALL() -#else -#define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALWAYS() -#endif - -/* name, frequency_units, duration_units */ -#define BCH_TIME_STATS() \ - BCH_TIME_STAT(mca_alloc, sec, us) \ - BCH_TIME_STAT(mca_scan, sec, ms) \ - BCH_TIME_STAT(btree_gc, sec, ms) \ - BCH_TIME_STAT(btree_coalesce, sec, ms) \ - BCH_TIME_STAT(btree_split, sec, us) \ - BCH_TIME_STAT(btree_sort, ms, us) \ - BCH_TIME_STAT(btree_read, ms, us) \ - BCH_TIME_STAT(journal_write, us, us) \ - BCH_TIME_STAT(journal_delay, ms, us) \ - BCH_TIME_STAT(journal_blocked, sec, ms) \ - BCH_TIME_STAT(journal_flush_seq, us, us) - -#include "alloc_types.h" -#include "blockdev_types.h" -#include "buckets_types.h" -#include "clock_types.h" -#include "io_types.h" -#include "journal_types.h" -#include "keylist_types.h" -#include "keybuf_types.h" -#include "move_types.h" -#include "stats_types.h" -#include "super_types.h" - -/* 256k, in sectors */ -#define BTREE_NODE_SIZE_MAX 512 - -/* - * Number of nodes we might have to allocate in a worst case btree split - * operation - we split all the way up to the root, then allocate a new root. - */ -#define btree_reserve_required_nodes(depth) (((depth) + 1) * 2 + 1) - -/* 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_reserve_required_nodes(BTREE_MAX_DEPTH) + GC_MERGE_NODES) - -/* Size of the freelist we allocate btree nodes from: */ -#define BTREE_NODE_RESERVE (BTREE_RESERVE_MAX * 2) - -struct btree; -struct crypto_blkcipher; -struct crypto_ahash; - -enum gc_phase { - GC_PHASE_SB_METADATA = BTREE_ID_NR + 1, - GC_PHASE_PENDING_DELETE, - GC_PHASE_DONE -}; - -struct gc_pos { - enum gc_phase phase; - struct bpos pos; - unsigned level; -}; - -struct bch_member_cpu { - u64 nbuckets; /* device size */ - u16 first_bucket; /* index of first bucket used */ - u16 bucket_size; /* sectors */ - u8 state; - u8 tier; - u8 has_metadata; - u8 has_data; - u8 replacement; - u8 discard; - u8 valid; -}; - -struct bch_dev { - struct kobject kobj; - struct percpu_ref ref; - struct percpu_ref io_ref; - struct completion stop_complete; - struct completion offline_complete; - - struct bch_fs *fs; - - u8 dev_idx; - /* - * Cached version of this device's member info from superblock - * Committed by bch_write_super() -> bch_fs_mi_update() - */ - struct bch_member_cpu mi; - uuid_le uuid; - char name[BDEVNAME_SIZE]; - - struct bcache_superblock disk_sb; - - struct dev_group self; - - /* biosets used in cloned bios for replicas and moving_gc */ - struct bio_set replica_set; - - struct task_struct *alloc_thread; - - struct prio_set *disk_buckets; - - /* - * When allocating new buckets, prio_write() gets first dibs - since we - * may not be allocate at all without writing priorities and gens. - * prio_last_buckets[] contains the last buckets we wrote priorities to - * (so gc can mark them as metadata). - */ - u64 *prio_buckets; - u64 *prio_last_buckets; - spinlock_t prio_buckets_lock; - struct bio *bio_prio; - - /* - * 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) - */ - DECLARE_FIFO(long, free)[RESERVE_NR]; - DECLARE_FIFO(long, free_inc); - spinlock_t freelist_lock; - - size_t fifo_last_bucket; - - /* Allocation stuff: */ - - /* most out of date gen in the btree */ - u8 *oldest_gens; - struct bucket *buckets; - unsigned short bucket_bits; /* ilog2(bucket_size) */ - - /* last calculated minimum prio */ - u16 min_prio[2]; - - /* - * Bucket book keeping. The first element is updated by GC, the - * second contains a saved copy of the stats from the beginning - * of GC. - */ - struct bch_dev_usage __percpu *usage_percpu; - struct bch_dev_usage usage_cached; - - atomic_long_t saturated_count; - size_t inc_gen_needs_gc; - - struct mutex heap_lock; - DECLARE_HEAP(struct bucket_heap_entry, heap); - - /* Moving GC: */ - struct task_struct *moving_gc_read; - - struct bch_pd_controller moving_gc_pd; - - /* Tiering: */ - struct write_point tiering_write_point; - - struct write_point copygc_write_point; - - struct journal_device journal; - - struct work_struct io_error_work; - - /* The rest of this all shows up in sysfs */ -#define IO_ERROR_SHIFT 20 - atomic_t io_errors; - atomic_t io_count; - - atomic64_t meta_sectors_written; - atomic64_t btree_sectors_written; - u64 __percpu *sectors_written; -}; - -/* - * 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 { - BCH_FS_INITIAL_GC_DONE, - BCH_FS_DETACHING, - BCH_FS_EMERGENCY_RO, - BCH_FS_WRITE_DISABLE_COMPLETE, - BCH_FS_GC_STOPPING, - BCH_FS_GC_FAILURE, - BCH_FS_BDEV_MOUNTED, - BCH_FS_ERROR, - BCH_FS_FSCK_FIXED_ERRORS, -}; - -struct btree_debug { - unsigned id; - struct dentry *btree; - struct dentry *btree_format; - struct dentry *failed; -}; - -struct bch_tier { - unsigned idx; - struct task_struct *migrate; - struct bch_pd_controller pd; - - struct dev_group devs; -}; - -enum bch_fs_state { - BCH_FS_STARTING = 0, - BCH_FS_STOPPING, - BCH_FS_RO, - BCH_FS_RW, -}; - -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_opts opts; - - /* Updated by bch_sb_update():*/ - struct { - uuid_le uuid; - uuid_le user_uuid; - - u16 block_size; - u16 btree_node_size; - - u8 nr_devices; - u8 clean; - - u8 meta_replicas_have; - u8 data_replicas_have; - - u8 str_hash_type; - u8 encryption_type; - - u64 time_base_lo; - u32 time_base_hi; - u32 time_precision; - } sb; - - struct bch_sb *disk_sb; - unsigned disk_sb_order; - - unsigned short block_bits; /* ilog2(block_size) */ - - struct closure sb_write; - struct mutex sb_lock; - - struct backing_dev_info bdi; - - /* BTREE CACHE */ - struct bio_set btree_read_bio; - - struct btree_root btree_roots[BTREE_ID_NR]; - struct mutex btree_root_lock; - - bool btree_cache_table_init_done; - struct rhashtable btree_cache_table; - - /* - * We never free a struct btree, except on shutdown - we just put it on - * the btree_cache_freed list and reuse it later. This simplifies the - * code, and it doesn't cost us much memory as the memory usage is - * dominated by buffers that hold the actual btree node data and those - * can be freed - and the number of struct btrees allocated is - * effectively bounded. - * - * btree_cache_freeable effectively is a small cache - we use it because - * high order page allocations can be rather expensive, and it's quite - * common to delete and allocate btree nodes in quick succession. It - * should never grow past ~2-3 nodes in practice. - */ - struct mutex btree_cache_lock; - struct list_head btree_cache; - struct list_head btree_cache_freeable; - struct list_head btree_cache_freed; - - /* Number of elements in btree_cache + btree_cache_freeable lists */ - unsigned btree_cache_used; - unsigned btree_cache_reserve; - struct shrinker btree_cache_shrink; - - /* - * If we need to allocate memory for a new btree node and that - * allocation fails, we can cannibalize another node in the btree cache - * to satisfy the allocation - lock to guarantee only one thread does - * this at a time: - */ - struct closure_waitlist mca_wait; - struct task_struct *btree_cache_alloc_lock; - - 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 { - struct open_bucket *ob; - BKEY_PADDED(k); - } 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 workqueue_struct *wq; - /* copygc needs its own workqueue for index updates.. */ - struct workqueue_struct *copygc_wq; - - /* ALLOCATION */ - struct bch_pd_controller foreground_write_pd; - struct delayed_work pd_controllers_update; - unsigned pd_controllers_update_seconds; - spinlock_t foreground_write_pd_lock; - struct bch_write_op *write_wait_head; - struct bch_write_op *write_wait_tail; - - struct timer_list foreground_write_wakeup; - - /* - * These contain all r/w devices - i.e. devices we can currently - * allocate from: - */ - struct dev_group all_devs; - struct bch_tier tiers[BCH_TIER_MAX]; - /* NULL if we only have devices in one tier: */ - struct bch_tier *fastest_tier; - - 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; - - atomic64_t sectors_available; - - struct bch_fs_usage __percpu *usage_percpu; - struct bch_fs_usage usage_cached; - struct lglock usage_lock; - - struct mutex bucket_lock; - - struct closure_waitlist freelist_wait; - - /* - * 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 prio_clock prio_clock[2]; - - struct io_clock io_clock[2]; - - /* SECTOR ALLOCATOR */ - struct list_head open_buckets_open; - struct list_head open_buckets_free; - unsigned open_buckets_nr_free; - struct closure_waitlist open_buckets_wait; - spinlock_t open_buckets_lock; - struct open_bucket open_buckets[OPEN_BUCKETS_COUNT]; - - struct write_point btree_write_point; - - struct write_point write_points[WRITE_POINT_COUNT]; - struct write_point promote_write_point; - - /* - * This write point is used for migrating data off a device - * and can point to any other device. - * We can't use the normal write points because those will - * gang up n replicas, and for migration we want only one new - * replica. - */ - struct write_point migration_write_point; - - /* GARBAGE COLLECTION */ - struct task_struct *gc_thread; - atomic_t kick_gc; - - /* - * 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.) - * - * gc_cur_phase == GC_PHASE_DONE indicates that gc is finished/not - * currently running, and gc marks are currently valid - * - * 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; - - mempool_t lz4_workspace_pool; - void *zlib_workspace; - struct mutex zlib_workspace_lock; - mempool_t compression_bounce[2]; - - struct crypto_blkcipher *chacha20; - struct crypto_shash *poly1305; - - atomic64_t key_version; - - /* For punting bio submissions to workqueue, io.c */ - struct bio_list bio_submit_list; - struct work_struct bio_submit_work; - spinlock_t bio_submit_lock; - - struct bio_list read_retry_list; - struct work_struct read_retry_work; - spinlock_t read_retry_lock; - - /* FILESYSTEM */ - wait_queue_head_t writeback_wait; - atomic_t writeback_pages; - unsigned writeback_pages_max; - atomic_long_t nr_inodes; - - /* NOTIFICATIONS */ - struct mutex uevent_lock; - struct kobj_uevent_env uevent_env; - - /* DEBUG JUNK */ - struct dentry *debug; - struct btree_debug btree_debug[BTREE_ID_NR]; -#ifdef CONFIG_BCACHE_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; - - unsigned bucket_journal_seq; - - /* CACHING OTHER BLOCK DEVICES */ - mempool_t search; - struct radix_tree_root devices; - struct list_head cached_devs; - u64 cached_dev_sectors; - struct closure caching; - -#define CONGESTED_MAX 1024 - unsigned congested_last_us; - atomic_t congested; - - /* The rest of this all shows up in sysfs */ - unsigned congested_read_threshold_us; - unsigned congested_write_threshold_us; - - struct cache_accounting accounting; - atomic_long_t cache_read_races; - atomic_long_t writeback_keys_done; - atomic_long_t writeback_keys_failed; - - unsigned error_limit; - unsigned error_decay; - - unsigned foreground_write_ratelimit_enabled:1; - unsigned copy_gc_enabled:1; - unsigned tiering_enabled:1; - unsigned tiering_percent; - - /* - * foreground writes will be throttled when the number of free - * buckets is below this percentage - */ - unsigned foreground_target_percent; - -#define BCH_DEBUG_PARAM(name, description) bool name; - BCH_DEBUG_PARAMS_ALL() -#undef BCH_DEBUG_PARAM - -#define BCH_TIME_STAT(name, frequency_units, duration_units) \ - struct time_stats name##_time; - BCH_TIME_STATS() -#undef BCH_TIME_STAT -}; - -static inline bool bch_fs_running(struct bch_fs *c) -{ - return c->state == BCH_FS_RO || c->state == BCH_FS_RW; -} - -static inline unsigned bucket_pages(const struct bch_dev *ca) -{ - return ca->mi.bucket_size / PAGE_SECTORS; -} - -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->sb.block_size << 9; -} - -#endif /* _BCACHE_H */ |