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|
// SPDX-License-Identifier: GPL-2.0
/*
* Code for manipulating bucket marks for garbage collection.
*
* Copyright 2014 Datera, Inc.
*
* Bucket states:
* - free bucket: mark == 0
* The bucket contains no data and will not be read
*
* - allocator bucket: owned_by_allocator == 1
* The bucket is on a free list, or it is an open bucket
*
* - cached bucket: owned_by_allocator == 0 &&
* dirty_sectors == 0 &&
* cached_sectors > 0
* The bucket contains data but may be safely discarded as there are
* enough replicas of the data on other cache devices, or it has been
* written back to the backing device
*
* - dirty bucket: owned_by_allocator == 0 &&
* dirty_sectors > 0
* The bucket contains data that we must not discard (either only copy,
* or one of the 'main copies' for data requiring multiple replicas)
*
* - metadata bucket: owned_by_allocator == 0 && is_metadata == 1
* This is a btree node, journal or gen/prio bucket
*
* Lifecycle:
*
* bucket invalidated => bucket on freelist => open bucket =>
* [dirty bucket =>] cached bucket => bucket invalidated => ...
*
* Note that cache promotion can skip the dirty bucket step, as data
* is copied from a deeper tier to a shallower tier, onto a cached
* bucket.
* Note also that a cached bucket can spontaneously become dirty --
* see below.
*
* Only a traversal of the key space can determine whether a bucket is
* truly dirty or cached.
*
* Transitions:
*
* - free => allocator: bucket was invalidated
* - cached => allocator: bucket was invalidated
*
* - allocator => dirty: open bucket was filled up
* - allocator => cached: open bucket was filled up
* - allocator => metadata: metadata was allocated
*
* - dirty => cached: dirty sectors were copied to a deeper tier
* - dirty => free: dirty sectors were overwritten or moved (copy gc)
* - cached => free: cached sectors were overwritten
*
* - metadata => free: metadata was freed
*
* Oddities:
* - cached => dirty: a device was removed so formerly replicated data
* is no longer sufficiently replicated
* - free => cached: cannot happen
* - free => dirty: cannot happen
* - free => metadata: cannot happen
*/
#include "bcachefs.h"
#include "alloc.h"
#include "btree_gc.h"
#include "buckets.h"
#include "error.h"
#include "movinggc.h"
#include "trace.h"
#include <linux/preempt.h>
#ifdef DEBUG_BUCKETS
#define lg_local_lock lg_global_lock
#define lg_local_unlock lg_global_unlock
static void bch2_fs_stats_verify(struct bch_fs *c)
{
struct bch_fs_usage stats =
__bch2_fs_usage_read(c);
unsigned i;
for (i = 0; i < ARRAY_SIZE(stats.s); i++) {
if ((s64) stats.s[i].data[S_META] < 0)
panic("replicas %u meta underflow: %lli\n",
i + 1, stats.s[i].data[S_META]);
if ((s64) stats.s[i].data[S_DIRTY] < 0)
panic("replicas %u dirty underflow: %lli\n",
i + 1, stats.s[i].data[S_DIRTY]);
if ((s64) stats.s[i].persistent_reserved < 0)
panic("replicas %u reserved underflow: %lli\n",
i + 1, stats.s[i].persistent_reserved);
}
if ((s64) stats.online_reserved < 0)
panic("sectors_online_reserved underflow: %lli\n",
stats.online_reserved);
}
static void bch2_dev_stats_verify(struct bch_dev *ca)
{
struct bch_dev_usage stats =
__bch2_dev_usage_read(ca);
u64 n = ca->mi.nbuckets - ca->mi.first_bucket;
unsigned i;
for (i = 0; i < ARRAY_SIZE(stats.buckets); i++)
BUG_ON(stats.buckets[i] > n);
BUG_ON(stats.buckets_alloc > n);
BUG_ON(stats.buckets_unavailable > n);
}
static void bch2_disk_reservations_verify(struct bch_fs *c, int flags)
{
if (!(flags & BCH_DISK_RESERVATION_NOFAIL)) {
u64 used = __bch2_fs_sectors_used(c);
u64 cached = 0;
u64 avail = atomic64_read(&c->sectors_available);
int cpu;
for_each_possible_cpu(cpu)
cached += per_cpu_ptr(c->usage_percpu, cpu)->available_cache;
if (used + avail + cached > c->capacity)
panic("used %llu avail %llu cached %llu capacity %llu\n",
used, avail, cached, c->capacity);
}
}
#else
static void bch2_fs_stats_verify(struct bch_fs *c) {}
static void bch2_dev_stats_verify(struct bch_dev *ca) {}
static void bch2_disk_reservations_verify(struct bch_fs *c, int flags) {}
#endif
/*
* Clear journal_seq_valid for buckets for which it's not needed, to prevent
* wraparound:
*/
void bch2_bucket_seq_cleanup(struct bch_fs *c)
{
u16 last_seq_ondisk = c->journal.last_seq_ondisk;
struct bch_dev *ca;
struct bucket_array *buckets;
struct bucket *g;
struct bucket_mark m;
unsigned i;
for_each_member_device(ca, c, i) {
down_read(&ca->bucket_lock);
buckets = bucket_array(ca);
for_each_bucket(g, buckets) {
bucket_cmpxchg(g, m, ({
if (!m.journal_seq_valid ||
bucket_needs_journal_commit(m, last_seq_ondisk))
break;
m.journal_seq_valid = 0;
}));
}
up_read(&ca->bucket_lock);
}
}
#define bch2_usage_add(_acc, _stats) \
do { \
typeof(_acc) _a = (_acc), _s = (_stats); \
unsigned i; \
\
for (i = 0; i < sizeof(*_a) / sizeof(u64); i++) \
((u64 *) (_a))[i] += ((u64 *) (_s))[i]; \
} while (0)
#define bch2_usage_read_raw(_stats) \
({ \
typeof(*this_cpu_ptr(_stats)) _acc; \
int cpu; \
\
memset(&_acc, 0, sizeof(_acc)); \
\
for_each_possible_cpu(cpu) \
bch2_usage_add(&_acc, per_cpu_ptr((_stats), cpu)); \
\
_acc; \
})
#define bch2_usage_read_cached(_c, _cached, _uncached) \
({ \
typeof(_cached) _ret; \
unsigned _seq; \
\
do { \
_seq = read_seqcount_begin(&(_c)->gc_pos_lock); \
_ret = (_c)->gc_pos.phase == GC_PHASE_DONE \
? bch2_usage_read_raw(_uncached) \
: (_cached); \
} while (read_seqcount_retry(&(_c)->gc_pos_lock, _seq)); \
\
_ret; \
})
struct bch_dev_usage __bch2_dev_usage_read(struct bch_dev *ca)
{
return bch2_usage_read_raw(ca->usage_percpu);
}
struct bch_dev_usage bch2_dev_usage_read(struct bch_fs *c, struct bch_dev *ca)
{
return bch2_usage_read_cached(c, ca->usage_cached, ca->usage_percpu);
}
struct bch_fs_usage
__bch2_fs_usage_read(struct bch_fs *c)
{
return bch2_usage_read_raw(c->usage_percpu);
}
struct bch_fs_usage
bch2_fs_usage_read(struct bch_fs *c)
{
return bch2_usage_read_cached(c,
c->usage_cached,
c->usage_percpu);
}
struct fs_usage_sum {
u64 data;
u64 reserved;
};
static inline struct fs_usage_sum __fs_usage_sum(struct bch_fs_usage stats)
{
struct fs_usage_sum sum = { 0 };
unsigned i;
for (i = 0; i < ARRAY_SIZE(stats.s); i++) {
sum.data += (stats.s[i].data[S_META] +
stats.s[i].data[S_DIRTY]) * (i + 1);
sum.reserved += stats.s[i].persistent_reserved * (i + 1);
}
sum.reserved += stats.online_reserved;
return sum;
}
#define RESERVE_FACTOR 6
static u64 reserve_factor(u64 r)
{
return r + (round_up(r, (1 << RESERVE_FACTOR)) >> RESERVE_FACTOR);
}
static u64 avail_factor(u64 r)
{
return (r << RESERVE_FACTOR) / (1 << RESERVE_FACTOR) + 1;
}
u64 __bch2_fs_sectors_used(struct bch_fs *c, struct bch_fs_usage stats)
{
struct fs_usage_sum sum = __fs_usage_sum(stats);
return sum.data + reserve_factor(sum.reserved);
}
u64 bch2_fs_sectors_used(struct bch_fs *c, struct bch_fs_usage stats)
{
return min(c->capacity, __bch2_fs_sectors_used(c, stats));
}
u64 bch2_fs_sectors_free(struct bch_fs *c, struct bch_fs_usage stats)
{
return avail_factor(c->capacity - bch2_fs_sectors_used(c, stats));
}
static inline int is_unavailable_bucket(struct bucket_mark m)
{
return !is_available_bucket(m);
}
static inline int is_fragmented_bucket(struct bucket_mark m,
struct bch_dev *ca)
{
if (!m.owned_by_allocator &&
m.data_type == BCH_DATA_USER &&
bucket_sectors_used(m))
return max_t(int, 0, (int) ca->mi.bucket_size -
bucket_sectors_used(m));
return 0;
}
static inline enum bch_data_type bucket_type(struct bucket_mark m)
{
return m.cached_sectors && !m.dirty_sectors
? BCH_DATA_CACHED
: m.data_type;
}
static bool bucket_became_unavailable(struct bch_fs *c,
struct bucket_mark old,
struct bucket_mark new)
{
return is_available_bucket(old) &&
!is_available_bucket(new) &&
(!c || c->gc_pos.phase == GC_PHASE_DONE);
}
void bch2_fs_usage_apply(struct bch_fs *c,
struct bch_fs_usage *stats,
struct disk_reservation *disk_res,
struct gc_pos gc_pos)
{
struct fs_usage_sum sum = __fs_usage_sum(*stats);
s64 added = sum.data + sum.reserved;
/*
* Not allowed to reduce sectors_available except by getting a
* reservation:
*/
BUG_ON(added > (s64) (disk_res ? disk_res->sectors : 0));
if (added > 0) {
disk_res->sectors -= added;
stats->online_reserved -= added;
}
percpu_down_read(&c->usage_lock);
preempt_disable();
/* online_reserved not subject to gc: */
this_cpu_add(c->usage_percpu->online_reserved, stats->online_reserved);
stats->online_reserved = 0;
if (!gc_will_visit(c, gc_pos))
bch2_usage_add(this_cpu_ptr(c->usage_percpu), stats);
bch2_fs_stats_verify(c);
preempt_enable();
percpu_up_read(&c->usage_lock);
memset(stats, 0, sizeof(*stats));
}
static void bch2_dev_usage_update(struct bch_fs *c, struct bch_dev *ca,
struct bucket_mark old, struct bucket_mark new)
{
struct bch_dev_usage *dev_usage;
if (c)
percpu_rwsem_assert_held(&c->usage_lock);
if (old.data_type && new.data_type &&
old.data_type != new.data_type) {
BUG_ON(!c);
bch2_fs_inconsistent(c,
"different types of data in same bucket: %s, %s",
bch2_data_types[old.data_type],
bch2_data_types[new.data_type]);
}
preempt_disable();
dev_usage = this_cpu_ptr(ca->usage_percpu);
dev_usage->buckets[bucket_type(old)]--;
dev_usage->buckets[bucket_type(new)]++;
dev_usage->buckets_alloc +=
(int) new.owned_by_allocator - (int) old.owned_by_allocator;
dev_usage->buckets_unavailable +=
is_unavailable_bucket(new) - is_unavailable_bucket(old);
dev_usage->sectors[old.data_type] -= old.dirty_sectors;
dev_usage->sectors[new.data_type] += new.dirty_sectors;
dev_usage->sectors[BCH_DATA_CACHED] +=
(int) new.cached_sectors - (int) old.cached_sectors;
dev_usage->sectors_fragmented +=
is_fragmented_bucket(new, ca) - is_fragmented_bucket(old, ca);
preempt_enable();
if (!is_available_bucket(old) && is_available_bucket(new))
bch2_wake_allocator(ca);
bch2_dev_stats_verify(ca);
}
#define bucket_data_cmpxchg(c, ca, g, new, expr) \
({ \
struct bucket_mark _old = bucket_cmpxchg(g, new, expr); \
\
bch2_dev_usage_update(c, ca, _old, new); \
_old; \
})
bool bch2_invalidate_bucket(struct bch_fs *c, struct bch_dev *ca,
size_t b, struct bucket_mark *old)
{
struct bucket *g;
struct bucket_mark new;
percpu_rwsem_assert_held(&c->usage_lock);
g = bucket(ca, b);
*old = bucket_data_cmpxchg(c, ca, g, new, ({
if (!is_available_bucket(new))
return false;
new.owned_by_allocator = 1;
new.data_type = 0;
new.cached_sectors = 0;
new.dirty_sectors = 0;
new.gen++;
}));
if (!old->owned_by_allocator && old->cached_sectors)
trace_invalidate(ca, bucket_to_sector(ca, b),
old->cached_sectors);
return true;
}
void bch2_mark_alloc_bucket(struct bch_fs *c, struct bch_dev *ca,
size_t b, bool owned_by_allocator,
struct gc_pos pos, unsigned flags)
{
struct bucket *g;
struct bucket_mark old, new;
percpu_rwsem_assert_held(&c->usage_lock);
g = bucket(ca, b);
if (!(flags & BCH_BUCKET_MARK_GC_LOCK_HELD) &&
gc_will_visit(c, pos))
return;
old = bucket_data_cmpxchg(c, ca, g, new, ({
new.owned_by_allocator = owned_by_allocator;
}));
BUG_ON(!owned_by_allocator && !old.owned_by_allocator &&
c->gc_pos.phase == GC_PHASE_DONE);
}
#define saturated_add(ca, dst, src, max) \
do { \
BUG_ON((int) (dst) + (src) < 0); \
if ((dst) == (max)) \
; \
else if ((dst) + (src) <= (max)) \
dst += (src); \
else { \
dst = (max); \
trace_sectors_saturated(ca); \
} \
} while (0)
void bch2_mark_metadata_bucket(struct bch_fs *c, struct bch_dev *ca,
size_t b, enum bch_data_type type,
unsigned sectors, struct gc_pos pos,
unsigned flags)
{
struct bucket *g;
struct bucket_mark old, new;
BUG_ON(!type);
if (likely(c)) {
percpu_rwsem_assert_held(&c->usage_lock);
if (!(flags & BCH_BUCKET_MARK_GC_LOCK_HELD) &&
gc_will_visit(c, pos))
return;
}
rcu_read_lock();
g = bucket(ca, b);
old = bucket_data_cmpxchg(c, ca, g, new, ({
saturated_add(ca, new.dirty_sectors, sectors,
GC_MAX_SECTORS_USED);
new.data_type = type;
}));
rcu_read_unlock();
BUG_ON(!(flags & BCH_BUCKET_MARK_MAY_MAKE_UNAVAILABLE) &&
bucket_became_unavailable(c, old, new));
}
/* Reverting this until the copygc + compression issue is fixed: */
static int __disk_sectors(struct bch_extent_crc_unpacked crc, unsigned sectors)
{
if (!sectors)
return 0;
return max(1U, DIV_ROUND_UP(sectors * crc.compressed_size,
crc.uncompressed_size));
}
/*
* Checking against gc's position has to be done here, inside the cmpxchg()
* loop, to avoid racing with the start of gc clearing all the marks - GC does
* that with the gc pos seqlock held.
*/
static void bch2_mark_pointer(struct bch_fs *c,
struct bkey_s_c_extent e,
const struct bch_extent_ptr *ptr,
struct bch_extent_crc_unpacked crc,
s64 sectors, enum s_alloc type,
struct bch_fs_usage *stats,
u64 journal_seq, unsigned flags)
{
struct bucket_mark old, new;
unsigned saturated;
struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
struct bucket *g = PTR_BUCKET(ca, ptr);
enum bch_data_type data_type = type == S_META
? BCH_DATA_BTREE : BCH_DATA_USER;
u64 v;
if (crc.compression_type) {
unsigned old_sectors, new_sectors;
if (sectors > 0) {
old_sectors = 0;
new_sectors = sectors;
} else {
old_sectors = e.k->size;
new_sectors = e.k->size + sectors;
}
sectors = -__disk_sectors(crc, old_sectors)
+__disk_sectors(crc, new_sectors);
}
if (flags & BCH_BUCKET_MARK_GC_WILL_VISIT) {
if (journal_seq)
bucket_cmpxchg(g, new, ({
new.journal_seq_valid = 1;
new.journal_seq = journal_seq;
}));
return;
}
v = atomic64_read(&g->_mark.v);
do {
new.v.counter = old.v.counter = v;
saturated = 0;
/*
* Check this after reading bucket mark to guard against
* the allocator invalidating a bucket after we've already
* checked the gen
*/
if (gen_after(new.gen, ptr->gen)) {
BUG_ON(!test_bit(BCH_FS_ALLOC_READ_DONE, &c->flags));
EBUG_ON(!ptr->cached &&
test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags));
return;
}
if (!ptr->cached &&
new.dirty_sectors == GC_MAX_SECTORS_USED &&
sectors < 0)
saturated = -sectors;
if (ptr->cached)
saturated_add(ca, new.cached_sectors, sectors,
GC_MAX_SECTORS_USED);
else
saturated_add(ca, new.dirty_sectors, sectors,
GC_MAX_SECTORS_USED);
if (!new.dirty_sectors &&
!new.cached_sectors) {
new.data_type = 0;
if (journal_seq) {
new.journal_seq_valid = 1;
new.journal_seq = journal_seq;
}
} else {
new.data_type = data_type;
}
if (flags & BCH_BUCKET_MARK_NOATOMIC) {
g->_mark = new;
break;
}
} while ((v = atomic64_cmpxchg(&g->_mark.v,
old.v.counter,
new.v.counter)) != old.v.counter);
bch2_dev_usage_update(c, ca, old, new);
BUG_ON(!(flags & BCH_BUCKET_MARK_MAY_MAKE_UNAVAILABLE) &&
bucket_became_unavailable(c, old, new));
if (saturated &&
atomic_long_add_return(saturated,
&ca->saturated_count) >=
bucket_to_sector(ca, ca->free_inc.size)) {
if (c->gc_thread) {
trace_gc_sectors_saturated(c);
wake_up_process(c->gc_thread);
}
}
}
void bch2_mark_key(struct bch_fs *c, struct bkey_s_c k,
s64 sectors, bool metadata,
struct gc_pos pos,
struct bch_fs_usage *stats,
u64 journal_seq, unsigned flags)
{
/*
* synchronization w.r.t. GC:
*
* Normally, bucket sector counts/marks are updated on the fly, as
* references are added/removed from the btree, the lists of buckets the
* allocator owns, other metadata buckets, etc.
*
* When GC is in progress and going to mark this reference, we do _not_
* mark this reference here, to avoid double counting - GC will count it
* when it gets to it.
*
* To know whether we should mark a given reference (GC either isn't
* running, or has already marked references at this position) we
* construct a total order for everything GC walks. Then, we can simply
* compare the position of the reference we're marking - @pos - with
* GC's current position. If GC is going to mark this reference, GC's
* current position will be less than @pos; if GC's current position is
* greater than @pos GC has either already walked this position, or
* isn't running.
*
* To avoid racing with GC's position changing, we have to deal with
* - GC's position being set to GC_POS_MIN when GC starts:
* usage_lock guards against this
* - GC's position overtaking @pos: we guard against this with
* whatever lock protects the data structure the reference lives in
* (e.g. the btree node lock, or the relevant allocator lock).
*/
percpu_down_read(&c->usage_lock);
if (!(flags & BCH_BUCKET_MARK_GC_LOCK_HELD) &&
gc_will_visit(c, pos))
flags |= BCH_BUCKET_MARK_GC_WILL_VISIT;
if (!stats)
stats = this_cpu_ptr(c->usage_percpu);
switch (k.k->type) {
case BCH_EXTENT:
case BCH_EXTENT_CACHED: {
struct bkey_s_c_extent e = bkey_s_c_to_extent(k);
const struct bch_extent_ptr *ptr;
struct bch_extent_crc_unpacked crc;
enum s_alloc type = metadata ? S_META : S_DIRTY;
unsigned replicas = 0;
BUG_ON(metadata && bkey_extent_is_cached(e.k));
BUG_ON(!sectors);
extent_for_each_ptr_crc(e, ptr, crc) {
bch2_mark_pointer(c, e, ptr, crc, sectors, type,
stats, journal_seq, flags);
replicas += !ptr->cached;
}
if (replicas) {
BUG_ON(replicas - 1 > ARRAY_SIZE(stats->s));
stats->s[replicas - 1].data[type] += sectors;
}
break;
}
case BCH_RESERVATION: {
struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
if (r.v->nr_replicas) {
BUG_ON(r.v->nr_replicas - 1 > ARRAY_SIZE(stats->s));
stats->s[r.v->nr_replicas - 1].persistent_reserved += sectors;
}
break;
}
}
percpu_up_read(&c->usage_lock);
}
/* Disk reservations: */
static u64 __recalc_sectors_available(struct bch_fs *c)
{
int cpu;
for_each_possible_cpu(cpu)
per_cpu_ptr(c->usage_percpu, cpu)->available_cache = 0;
return bch2_fs_sectors_free(c, bch2_fs_usage_read(c));
}
/* Used by gc when it's starting: */
void bch2_recalc_sectors_available(struct bch_fs *c)
{
percpu_down_write(&c->usage_lock);
atomic64_set(&c->sectors_available, __recalc_sectors_available(c));
percpu_up_write(&c->usage_lock);
}
void __bch2_disk_reservation_put(struct bch_fs *c, struct disk_reservation *res)
{
percpu_down_read(&c->usage_lock);
this_cpu_sub(c->usage_percpu->online_reserved,
res->sectors);
bch2_fs_stats_verify(c);
percpu_up_read(&c->usage_lock);
res->sectors = 0;
}
#define SECTORS_CACHE 1024
int bch2_disk_reservation_add(struct bch_fs *c, struct disk_reservation *res,
unsigned sectors, int flags)
{
struct bch_fs_usage *stats;
u64 old, v, get;
s64 sectors_available;
int ret;
percpu_down_read(&c->usage_lock);
preempt_disable();
stats = this_cpu_ptr(c->usage_percpu);
if (sectors <= stats->available_cache)
goto out;
v = atomic64_read(&c->sectors_available);
do {
old = v;
get = min((u64) sectors + SECTORS_CACHE, old);
if (get < sectors) {
preempt_enable();
percpu_up_read(&c->usage_lock);
goto recalculate;
}
} while ((v = atomic64_cmpxchg(&c->sectors_available,
old, old - get)) != old);
stats->available_cache += get;
out:
stats->available_cache -= sectors;
stats->online_reserved += sectors;
res->sectors += sectors;
bch2_disk_reservations_verify(c, flags);
bch2_fs_stats_verify(c);
preempt_enable();
percpu_up_read(&c->usage_lock);
return 0;
recalculate:
/*
* GC recalculates sectors_available when it starts, so that hopefully
* we don't normally end up blocking here:
*/
/*
* Piss fuck, we can be called from extent_insert_fixup() with btree
* locks held:
*/
if (!(flags & BCH_DISK_RESERVATION_GC_LOCK_HELD)) {
if (!(flags & BCH_DISK_RESERVATION_BTREE_LOCKS_HELD))
down_read(&c->gc_lock);
else if (!down_read_trylock(&c->gc_lock))
return -EINTR;
}
percpu_down_write(&c->usage_lock);
sectors_available = __recalc_sectors_available(c);
if (sectors <= sectors_available ||
(flags & BCH_DISK_RESERVATION_NOFAIL)) {
atomic64_set(&c->sectors_available,
max_t(s64, 0, sectors_available - sectors));
stats->online_reserved += sectors;
res->sectors += sectors;
ret = 0;
bch2_disk_reservations_verify(c, flags);
} else {
atomic64_set(&c->sectors_available, sectors_available);
ret = -ENOSPC;
}
bch2_fs_stats_verify(c);
percpu_up_write(&c->usage_lock);
if (!(flags & BCH_DISK_RESERVATION_GC_LOCK_HELD))
up_read(&c->gc_lock);
return ret;
}
/* Startup/shutdown: */
static void buckets_free_rcu(struct rcu_head *rcu)
{
struct bucket_array *buckets =
container_of(rcu, struct bucket_array, rcu);
kvpfree(buckets,
sizeof(struct bucket_array) +
buckets->nbuckets * sizeof(struct bucket));
}
int bch2_dev_buckets_resize(struct bch_fs *c, struct bch_dev *ca, u64 nbuckets)
{
struct bucket_array *buckets = NULL, *old_buckets = NULL;
unsigned long *buckets_dirty = NULL;
u8 *oldest_gens = NULL;
alloc_fifo free[RESERVE_NR];
alloc_fifo free_inc;
alloc_heap alloc_heap;
copygc_heap copygc_heap;
size_t btree_reserve = DIV_ROUND_UP(BTREE_NODE_RESERVE,
ca->mi.bucket_size / c->opts.btree_node_size);
/* XXX: these should be tunable */
size_t reserve_none = max_t(size_t, 4, ca->mi.nbuckets >> 9);
size_t copygc_reserve = max_t(size_t, 16, ca->mi.nbuckets >> 7);
size_t free_inc_reserve = copygc_reserve / 2;
bool resize = ca->buckets != NULL,
start_copygc = ca->copygc_thread != NULL;
int ret = -ENOMEM;
unsigned i;
memset(&free, 0, sizeof(free));
memset(&free_inc, 0, sizeof(free_inc));
memset(&alloc_heap, 0, sizeof(alloc_heap));
memset(©gc_heap, 0, sizeof(copygc_heap));
if (!(buckets = kvpmalloc(sizeof(struct bucket_array) +
nbuckets * sizeof(struct bucket),
GFP_KERNEL|__GFP_ZERO)) ||
!(oldest_gens = kvpmalloc(nbuckets * sizeof(u8),
GFP_KERNEL|__GFP_ZERO)) ||
!(buckets_dirty = kvpmalloc(BITS_TO_LONGS(nbuckets) *
sizeof(unsigned long),
GFP_KERNEL|__GFP_ZERO)) ||
!init_fifo(&free[RESERVE_BTREE], btree_reserve, GFP_KERNEL) ||
!init_fifo(&free[RESERVE_MOVINGGC],
copygc_reserve, GFP_KERNEL) ||
!init_fifo(&free[RESERVE_NONE], reserve_none, GFP_KERNEL) ||
!init_fifo(&free_inc, free_inc_reserve, GFP_KERNEL) ||
!init_heap(&alloc_heap, free_inc_reserve, GFP_KERNEL) ||
!init_heap(©gc_heap, copygc_reserve, GFP_KERNEL))
goto err;
buckets->first_bucket = ca->mi.first_bucket;
buckets->nbuckets = nbuckets;
bch2_copygc_stop(ca);
if (resize) {
down_write(&c->gc_lock);
down_write(&ca->bucket_lock);
percpu_down_write(&c->usage_lock);
}
old_buckets = bucket_array(ca);
if (resize) {
size_t n = min(buckets->nbuckets, old_buckets->nbuckets);
memcpy(buckets->b,
old_buckets->b,
n * sizeof(struct bucket));
memcpy(oldest_gens,
ca->oldest_gens,
n * sizeof(u8));
memcpy(buckets_dirty,
ca->buckets_dirty,
BITS_TO_LONGS(n) * sizeof(unsigned long));
}
rcu_assign_pointer(ca->buckets, buckets);
buckets = old_buckets;
swap(ca->oldest_gens, oldest_gens);
swap(ca->buckets_dirty, buckets_dirty);
if (resize)
percpu_up_write(&c->usage_lock);
spin_lock(&c->freelist_lock);
for (i = 0; i < RESERVE_NR; i++) {
fifo_move(&free[i], &ca->free[i]);
swap(ca->free[i], free[i]);
}
fifo_move(&free_inc, &ca->free_inc);
swap(ca->free_inc, free_inc);
spin_unlock(&c->freelist_lock);
/* with gc lock held, alloc_heap can't be in use: */
swap(ca->alloc_heap, alloc_heap);
/* and we shut down copygc: */
swap(ca->copygc_heap, copygc_heap);
nbuckets = ca->mi.nbuckets;
if (resize) {
up_write(&ca->bucket_lock);
up_write(&c->gc_lock);
}
if (start_copygc &&
bch2_copygc_start(c, ca))
bch_err(ca, "error restarting copygc thread");
ret = 0;
err:
free_heap(©gc_heap);
free_heap(&alloc_heap);
free_fifo(&free_inc);
for (i = 0; i < RESERVE_NR; i++)
free_fifo(&free[i]);
kvpfree(buckets_dirty,
BITS_TO_LONGS(nbuckets) * sizeof(unsigned long));
kvpfree(oldest_gens,
nbuckets * sizeof(u8));
if (buckets)
call_rcu(&old_buckets->rcu, buckets_free_rcu);
return ret;
}
void bch2_dev_buckets_free(struct bch_dev *ca)
{
unsigned i;
free_heap(&ca->copygc_heap);
free_heap(&ca->alloc_heap);
free_fifo(&ca->free_inc);
for (i = 0; i < RESERVE_NR; i++)
free_fifo(&ca->free[i]);
kvpfree(ca->buckets_dirty,
BITS_TO_LONGS(ca->mi.nbuckets) * sizeof(unsigned long));
kvpfree(ca->oldest_gens, ca->mi.nbuckets * sizeof(u8));
kvpfree(rcu_dereference_protected(ca->buckets, 1),
sizeof(struct bucket_array) +
ca->mi.nbuckets * sizeof(struct bucket));
free_percpu(ca->usage_percpu);
}
int bch2_dev_buckets_alloc(struct bch_fs *c, struct bch_dev *ca)
{
if (!(ca->usage_percpu = alloc_percpu(struct bch_dev_usage)))
return -ENOMEM;
return bch2_dev_buckets_resize(c, ca, ca->mi.nbuckets);;
}
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