Files
tromcho.net/blockstore_impl.cpp
T
Vitaliy Filippov 4a2dcf7b6b Update the license to VNPL 1.1
VNPL 1.1 is slightly reworded to make it clear that proprietary software
interacting with Vitastor and providing some kind of service to end users isn't
a "Proxy Program" if it's not specially designed to be used with Vitastor.

For example, Windows OS running in a virtual machine stored in a Vitastor
cluster clearly isn't.
2021-02-25 23:55:33 +03:00

597 lines
19 KiB
C++

// Copyright (c) Vitaliy Filippov, 2019+
// License: VNPL-1.1 (see README.md for details)
#include "blockstore_impl.h"
blockstore_impl_t::blockstore_impl_t(blockstore_config_t & config, ring_loop_t *ringloop)
{
assert(sizeof(blockstore_op_private_t) <= BS_OP_PRIVATE_DATA_SIZE);
this->ringloop = ringloop;
ring_consumer.loop = [this]() { loop(); };
ringloop->register_consumer(&ring_consumer);
initialized = 0;
zero_object = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, block_size);
data_fd = meta_fd = journal.fd = -1;
parse_config(config);
try
{
open_data();
open_meta();
open_journal();
calc_lengths();
data_alloc = new allocator(block_count);
}
catch (std::exception & e)
{
if (data_fd >= 0)
close(data_fd);
if (meta_fd >= 0 && meta_fd != data_fd)
close(meta_fd);
if (journal.fd >= 0 && journal.fd != meta_fd)
close(journal.fd);
throw;
}
flusher = new journal_flusher_t(flusher_count, this);
}
blockstore_impl_t::~blockstore_impl_t()
{
delete data_alloc;
delete flusher;
free(zero_object);
ringloop->unregister_consumer(&ring_consumer);
if (data_fd >= 0)
close(data_fd);
if (meta_fd >= 0 && meta_fd != data_fd)
close(meta_fd);
if (journal.fd >= 0 && journal.fd != meta_fd)
close(journal.fd);
if (metadata_buffer)
free(metadata_buffer);
if (clean_bitmap)
free(clean_bitmap);
}
bool blockstore_impl_t::is_started()
{
return initialized == 10;
}
bool blockstore_impl_t::is_stalled()
{
return queue_stall;
}
// main event loop - produce requests
void blockstore_impl_t::loop()
{
// FIXME: initialized == 10 is ugly
if (initialized != 10)
{
// read metadata, then journal
if (initialized == 0)
{
metadata_init_reader = new blockstore_init_meta(this);
initialized = 1;
}
if (initialized == 1)
{
int res = metadata_init_reader->loop();
if (!res)
{
delete metadata_init_reader;
metadata_init_reader = NULL;
journal_init_reader = new blockstore_init_journal(this);
initialized = 2;
}
}
if (initialized == 2)
{
int res = journal_init_reader->loop();
if (!res)
{
delete journal_init_reader;
journal_init_reader = NULL;
initialized = 10;
ringloop->wakeup();
}
}
}
else
{
// try to submit ops
unsigned initial_ring_space = ringloop->space_left();
// FIXME: rework this "sync polling"
auto cur_sync = in_progress_syncs.begin();
while (cur_sync != in_progress_syncs.end())
{
if (continue_sync(*cur_sync) != 2)
{
// List is unmodified
cur_sync++;
}
else
{
cur_sync = in_progress_syncs.begin();
}
}
auto cur = submit_queue.begin();
int has_writes = 0;
while (cur != submit_queue.end())
{
auto op_ptr = cur;
auto op = *(cur++);
// FIXME: This needs some simplification
// Writes should not block reads if the ring is not full and reads don't depend on them
// In all other cases we should stop submission
if (PRIV(op)->wait_for)
{
check_wait(op);
if (PRIV(op)->wait_for == WAIT_SQE)
{
break;
}
else if (PRIV(op)->wait_for)
{
if (op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE || op->opcode == BS_OP_DELETE)
{
has_writes = 2;
}
continue;
}
}
unsigned ring_space = ringloop->space_left();
unsigned prev_sqe_pos = ringloop->save();
bool dequeue_op = false;
if (op->opcode == BS_OP_READ)
{
dequeue_op = dequeue_read(op);
}
else if (op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE)
{
if (has_writes == 2)
{
// Some writes already could not be submitted
continue;
}
dequeue_op = dequeue_write(op);
has_writes = dequeue_op ? 1 : 2;
}
else if (op->opcode == BS_OP_DELETE)
{
if (has_writes == 2)
{
// Some writes already could not be submitted
continue;
}
dequeue_op = dequeue_del(op);
has_writes = dequeue_op ? 1 : 2;
}
else if (op->opcode == BS_OP_SYNC)
{
// wait for all small writes to be submitted
// wait for all big writes to complete, submit data device fsync
// wait for the data device fsync to complete, then submit journal writes for big writes
// then submit an fsync operation
if (has_writes)
{
// Can't submit SYNC before previous writes
continue;
}
dequeue_op = dequeue_sync(op);
}
else if (op->opcode == BS_OP_STABLE)
{
dequeue_op = dequeue_stable(op);
}
else if (op->opcode == BS_OP_ROLLBACK)
{
dequeue_op = dequeue_rollback(op);
}
else if (op->opcode == BS_OP_LIST)
{
// LIST doesn't need to be blocked by previous modifications,
// it only needs to include all in-progress writes as they're guaranteed
// to be readable and stabilizable/rollbackable by subsequent operations
process_list(op);
dequeue_op = true;
}
if (dequeue_op)
{
submit_queue.erase(op_ptr);
}
else
{
ringloop->restore(prev_sqe_pos);
if (PRIV(op)->wait_for == WAIT_SQE)
{
PRIV(op)->wait_detail = 1 + ring_space;
// ring is full, stop submission
break;
}
}
}
if (!readonly)
{
flusher->loop();
}
int ret = ringloop->submit();
if (ret < 0)
{
throw std::runtime_error(std::string("io_uring_submit: ") + strerror(-ret));
}
if ((initial_ring_space - ringloop->space_left()) > 0)
{
live = true;
}
queue_stall = !live && !ringloop->has_work();
live = false;
}
}
bool blockstore_impl_t::is_safe_to_stop()
{
// It's safe to stop blockstore when there are no in-flight operations,
// no in-progress syncs and flusher isn't doing anything
if (submit_queue.size() > 0 || in_progress_syncs.size() > 0 || !readonly && flusher->is_active())
{
return false;
}
if (unsynced_big_writes.size() > 0 || unsynced_small_writes.size() > 0)
{
if (!readonly && !stop_sync_submitted)
{
// We should sync the blockstore before unmounting
blockstore_op_t *op = new blockstore_op_t;
op->opcode = BS_OP_SYNC;
op->buf = NULL;
op->callback = [](blockstore_op_t *op)
{
delete op;
};
enqueue_op(op);
stop_sync_submitted = true;
}
return false;
}
return true;
}
void blockstore_impl_t::check_wait(blockstore_op_t *op)
{
if (PRIV(op)->wait_for == WAIT_SQE)
{
if (ringloop->space_left() < PRIV(op)->wait_detail)
{
// stop submission if there's still no free space
#ifdef BLOCKSTORE_DEBUG
printf("Still waiting for %lu SQE(s)\n", PRIV(op)->wait_detail);
#endif
return;
}
PRIV(op)->wait_for = 0;
}
else if (PRIV(op)->wait_for == WAIT_JOURNAL)
{
if (journal.used_start == PRIV(op)->wait_detail)
{
// do not submit
#ifdef BLOCKSTORE_DEBUG
printf("Still waiting to flush journal offset %08lx\n", PRIV(op)->wait_detail);
#endif
return;
}
flusher->release_trim();
PRIV(op)->wait_for = 0;
}
else if (PRIV(op)->wait_for == WAIT_JOURNAL_BUFFER)
{
int next = ((journal.cur_sector + 1) % journal.sector_count);
if (journal.sector_info[next].flush_count > 0 ||
journal.sector_info[next].dirty)
{
// do not submit
#ifdef BLOCKSTORE_DEBUG
printf("Still waiting for a journal buffer\n");
#endif
return;
}
PRIV(op)->wait_for = 0;
}
else if (PRIV(op)->wait_for == WAIT_FREE)
{
if (!data_alloc->get_free_count() && !flusher->is_active())
{
#ifdef BLOCKSTORE_DEBUG
printf("Still waiting for free space on the data device\n");
#endif
return;
}
PRIV(op)->wait_for = 0;
}
else
{
throw std::runtime_error("BUG: op->wait_for value is unexpected");
}
}
void blockstore_impl_t::enqueue_op(blockstore_op_t *op, bool first)
{
if (op->opcode < BS_OP_MIN || op->opcode > BS_OP_MAX ||
((op->opcode == BS_OP_READ || op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE) && (
op->offset >= block_size ||
op->len > block_size-op->offset ||
(op->len % disk_alignment)
)) ||
readonly && op->opcode != BS_OP_READ && op->opcode != BS_OP_LIST ||
first && (op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE))
{
// Basic verification not passed
op->retval = -EINVAL;
std::function<void (blockstore_op_t*)>(op->callback)(op);
return;
}
if (op->opcode == BS_OP_SYNC_STAB_ALL)
{
std::function<void(blockstore_op_t*)> *old_callback = new std::function<void(blockstore_op_t*)>(op->callback);
op->opcode = BS_OP_SYNC;
op->callback = [this, old_callback](blockstore_op_t *op)
{
if (op->retval >= 0 && unstable_writes.size() > 0)
{
op->opcode = BS_OP_STABLE;
op->len = unstable_writes.size();
obj_ver_id *vers = new obj_ver_id[op->len];
op->buf = vers;
int i = 0;
for (auto it = unstable_writes.begin(); it != unstable_writes.end(); it++, i++)
{
vers[i] = {
.oid = it->first,
.version = it->second,
};
}
unstable_writes.clear();
op->callback = [this, old_callback](blockstore_op_t *op)
{
obj_ver_id *vers = (obj_ver_id*)op->buf;
delete[] vers;
op->buf = NULL;
(*old_callback)(op);
delete old_callback;
};
this->enqueue_op(op);
}
else
{
(*old_callback)(op);
delete old_callback;
}
};
}
if ((op->opcode == BS_OP_WRITE || op->opcode == BS_OP_WRITE_STABLE || op->opcode == BS_OP_DELETE) && !enqueue_write(op))
{
std::function<void (blockstore_op_t*)>(op->callback)(op);
return;
}
if (op->opcode == BS_OP_SYNC && immediate_commit == IMMEDIATE_ALL)
{
op->retval = 0;
std::function<void (blockstore_op_t*)>(op->callback)(op);
return;
}
// Call constructor without allocating memory. We'll call destructor before returning op back
new ((void*)op->private_data) blockstore_op_private_t;
PRIV(op)->wait_for = 0;
PRIV(op)->op_state = 0;
PRIV(op)->pending_ops = 0;
if (!first)
{
submit_queue.push_back(op);
}
else
{
submit_queue.push_front(op);
}
ringloop->wakeup();
}
static bool replace_stable(object_id oid, uint64_t version, int search_start, int search_end, obj_ver_id* list)
{
while (search_start < search_end)
{
int pos = search_start+(search_end-search_start)/2;
if (oid < list[pos].oid)
{
search_end = pos;
}
else if (list[pos].oid < oid)
{
search_start = pos+1;
}
else
{
list[pos].version = version;
return true;
}
}
return false;
}
void blockstore_impl_t::process_list(blockstore_op_t *op)
{
uint32_t list_pg = op->offset;
uint32_t pg_count = op->len;
uint64_t pg_stripe_size = op->oid.stripe;
uint64_t min_inode = op->oid.inode;
uint64_t max_inode = op->version;
// Check PG
if (pg_count != 0 && (pg_stripe_size < MIN_BLOCK_SIZE || list_pg >= pg_count))
{
op->retval = -EINVAL;
FINISH_OP(op);
return;
}
// Copy clean_db entries (sorted)
int stable_count = 0, stable_alloc = clean_db.size() / (pg_count ? pg_count : 1);
obj_ver_id *stable = (obj_ver_id*)malloc(sizeof(obj_ver_id) * stable_alloc);
if (!stable)
{
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
{
auto clean_it = clean_db.begin(), clean_end = clean_db.end();
if ((min_inode != 0 || max_inode != 0) && min_inode <= max_inode)
{
clean_it = clean_db.lower_bound({
.inode = min_inode,
.stripe = 0,
});
clean_end = clean_db.upper_bound({
.inode = max_inode,
.stripe = UINT64_MAX,
});
}
for (; clean_it != clean_end; clean_it++)
{
if (!pg_count || ((clean_it->first.inode + clean_it->first.stripe / pg_stripe_size) % pg_count) == list_pg)
{
if (stable_count >= stable_alloc)
{
stable_alloc += 32768;
stable = (obj_ver_id*)realloc(stable, sizeof(obj_ver_id) * stable_alloc);
if (!stable)
{
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
}
stable[stable_count++] = {
.oid = clean_it->first,
.version = clean_it->second.version,
};
}
}
}
int clean_stable_count = stable_count;
// Copy dirty_db entries (sorted, too)
int unstable_count = 0, unstable_alloc = 0;
obj_ver_id *unstable = NULL;
{
auto dirty_it = dirty_db.begin(), dirty_end = dirty_db.end();
if ((min_inode != 0 || max_inode != 0) && min_inode <= max_inode)
{
dirty_it = dirty_db.lower_bound({
.oid = {
.inode = min_inode,
.stripe = 0,
},
.version = 0,
});
dirty_end = dirty_db.upper_bound({
.oid = {
.inode = max_inode,
.stripe = UINT64_MAX,
},
.version = UINT64_MAX,
});
}
for (; dirty_it != dirty_end; dirty_it++)
{
if (!pg_count || ((dirty_it->first.oid.inode + dirty_it->first.oid.stripe / pg_stripe_size) % pg_count) == list_pg)
{
if (IS_DELETE(dirty_it->second.state))
{
// Deletions are always stable, so try to zero out two possible entries
if (!replace_stable(dirty_it->first.oid, 0, 0, clean_stable_count, stable))
{
replace_stable(dirty_it->first.oid, 0, clean_stable_count, stable_count, stable);
}
}
else if (IS_STABLE(dirty_it->second.state))
{
// First try to replace a clean stable version in the first part of the list
if (!replace_stable(dirty_it->first.oid, dirty_it->first.version, 0, clean_stable_count, stable))
{
// Then try to replace the last dirty stable version in the second part of the list
if (stable_count > 0 && stable[stable_count-1].oid == dirty_it->first.oid)
{
stable[stable_count-1].version = dirty_it->first.version;
}
else
{
if (stable_count >= stable_alloc)
{
stable_alloc += 32768;
stable = (obj_ver_id*)realloc(stable, sizeof(obj_ver_id) * stable_alloc);
if (!stable)
{
if (unstable)
free(unstable);
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
}
stable[stable_count++] = dirty_it->first;
}
}
}
else
{
if (unstable_count >= unstable_alloc)
{
unstable_alloc += 32768;
unstable = (obj_ver_id*)realloc(unstable, sizeof(obj_ver_id) * unstable_alloc);
if (!unstable)
{
if (stable)
free(stable);
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
}
unstable[unstable_count++] = dirty_it->first;
}
}
}
}
// Remove zeroed out stable entries
int j = 0;
for (int i = 0; i < stable_count; i++)
{
if (stable[i].version != 0)
{
stable[j++] = stable[i];
}
}
stable_count = j;
if (stable_count+unstable_count > stable_alloc)
{
stable_alloc = stable_count+unstable_count;
stable = (obj_ver_id*)realloc(stable, sizeof(obj_ver_id) * stable_alloc);
if (!stable)
{
if (unstable)
free(unstable);
op->retval = -ENOMEM;
FINISH_OP(op);
return;
}
}
// Copy unstable entries
for (int i = 0; i < unstable_count; i++)
{
stable[j++] = unstable[i];
}
free(unstable);
op->version = stable_count;
op->retval = stable_count+unstable_count;
op->buf = stable;
FINISH_OP(op);
}