Spdk/lib/blob/blob_bs_dev.c
Evgeniy Kochetov 2e7a7fe530 blob: Optimize copy-on-write flow for clusters backed by zeroes device
Writing to unallocated cluster triggers copy-on-write sequence. If
this cluster is backed by zeroes device we can skip the copy part. For
a simple thin provisioned volume copy this shortcut is already
implemented because `blob->parent_id == SPDK_BLOBID_INVALID`. But this
will not work for thin provisioned volumes created from snapshot. In
this case we need to traverse the whole stack of underlying
`spdk_bs_dev` devices for specific cluster to check if it is zeroes
backed.

This patch adds `is_zeroes` operation to `spdk_bs_dev`. For zeroes
device it always returns 'true', for real bdev (`blob_bs_dev`) always
returns false, for another layer of `blob_bs_dev` does lba conversion
and forwards to backing device.

In blobstore's cluster copy flow we check if cluster is backed by
zeroes device and skip copy part if it is.

Signed-off-by: Evgeniy Kochetov <evgeniik@nvidia.com>
Change-Id: I640773ac78f8f466b96e96a34c3a6c3c91f87dab
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/13446
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Reviewed-by: Shuhei Matsumoto <smatsumoto@nvidia.com>
Reviewed-by: Aleksey Marchuk <alexeymar@nvidia.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
2022-09-05 12:49:46 +00:00

168 lines
4.8 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright (c) Intel Corporation.
* All rights reserved.
* Copyright (c) 2022 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
*/
#include "spdk/stdinc.h"
#include "spdk/blob.h"
#include "spdk/log.h"
#include "blobstore.h"
static void
blob_bs_dev_write(struct spdk_bs_dev *dev, struct spdk_io_channel *channel, void *payload,
uint64_t lba, uint32_t lba_count,
struct spdk_bs_dev_cb_args *cb_args)
{
cb_args->cb_fn(cb_args->channel, cb_args->cb_arg, -EPERM);
assert(false);
}
static void
blob_bs_dev_writev(struct spdk_bs_dev *dev, struct spdk_io_channel *channel,
struct iovec *iov, int iovcnt,
uint64_t lba, uint32_t lba_count,
struct spdk_bs_dev_cb_args *cb_args)
{
cb_args->cb_fn(cb_args->channel, cb_args->cb_arg, -EPERM);
assert(false);
}
static void
blob_bs_dev_writev_ext(struct spdk_bs_dev *dev, struct spdk_io_channel *channel,
struct iovec *iov, int iovcnt,
uint64_t lba, uint32_t lba_count,
struct spdk_bs_dev_cb_args *cb_args,
struct spdk_blob_ext_io_opts *ext_opts)
{
cb_args->cb_fn(cb_args->channel, cb_args->cb_arg, -EPERM);
assert(false);
}
static void
blob_bs_dev_write_zeroes(struct spdk_bs_dev *dev, struct spdk_io_channel *channel,
uint64_t lba, uint64_t lba_count,
struct spdk_bs_dev_cb_args *cb_args)
{
cb_args->cb_fn(cb_args->channel, cb_args->cb_arg, -EPERM);
assert(false);
}
static void
blob_bs_dev_unmap(struct spdk_bs_dev *dev, struct spdk_io_channel *channel,
uint64_t lba, uint64_t lba_count,
struct spdk_bs_dev_cb_args *cb_args)
{
cb_args->cb_fn(cb_args->channel, cb_args->cb_arg, -EPERM);
assert(false);
}
static void
blob_bs_dev_read_cpl(void *cb_arg, int bserrno)
{
struct spdk_bs_dev_cb_args *cb_args = (struct spdk_bs_dev_cb_args *)cb_arg;
cb_args->cb_fn(cb_args->channel, cb_args->cb_arg, bserrno);
}
static inline void
blob_bs_dev_read(struct spdk_bs_dev *dev, struct spdk_io_channel *channel, void *payload,
uint64_t lba, uint32_t lba_count, struct spdk_bs_dev_cb_args *cb_args)
{
struct spdk_blob_bs_dev *b = (struct spdk_blob_bs_dev *)dev;
spdk_blob_io_read(b->blob, channel, payload, lba, lba_count,
blob_bs_dev_read_cpl, cb_args);
}
static inline void
blob_bs_dev_readv(struct spdk_bs_dev *dev, struct spdk_io_channel *channel,
struct iovec *iov, int iovcnt,
uint64_t lba, uint32_t lba_count, struct spdk_bs_dev_cb_args *cb_args)
{
struct spdk_blob_bs_dev *b = (struct spdk_blob_bs_dev *)dev;
spdk_blob_io_readv(b->blob, channel, iov, iovcnt, lba, lba_count,
blob_bs_dev_read_cpl, cb_args);
}
static inline void
blob_bs_dev_readv_ext(struct spdk_bs_dev *dev, struct spdk_io_channel *channel,
struct iovec *iov, int iovcnt,
uint64_t lba, uint32_t lba_count, struct spdk_bs_dev_cb_args *cb_args,
struct spdk_blob_ext_io_opts *ext_opts)
{
struct spdk_blob_bs_dev *b = (struct spdk_blob_bs_dev *)dev;
spdk_blob_io_readv_ext(b->blob, channel, iov, iovcnt, lba, lba_count,
blob_bs_dev_read_cpl, cb_args, ext_opts);
}
static void
blob_bs_dev_destroy_cpl(void *cb_arg, int bserrno)
{
if (bserrno != 0) {
SPDK_ERRLOG("Error on blob_bs_dev destroy: %d", bserrno);
}
/* Free blob_bs_dev */
free(cb_arg);
}
static void
blob_bs_dev_destroy(struct spdk_bs_dev *bs_dev)
{
struct spdk_blob_bs_dev *b = (struct spdk_blob_bs_dev *)bs_dev;
spdk_blob_close(b->blob, blob_bs_dev_destroy_cpl, b);
}
static bool
blob_bs_is_zeroes(struct spdk_bs_dev *dev, uint64_t lba, uint64_t lba_count)
{
struct spdk_blob_bs_dev *b = (struct spdk_blob_bs_dev *)dev;
struct spdk_blob *blob = b->blob;
assert(lba == bs_cluster_to_lba(blob->bs, bs_lba_to_cluster(blob->bs, lba)));
assert(lba_count == bs_dev_byte_to_lba(dev, blob->bs->cluster_sz));
if (bs_io_unit_is_allocated(blob, lba)) {
return false;
}
assert(blob->back_bs_dev != NULL);
return blob->back_bs_dev->is_zeroes(blob->back_bs_dev,
bs_io_unit_to_back_dev_lba(blob, lba),
bs_io_unit_to_back_dev_lba(blob, lba_count));
}
struct spdk_bs_dev *
bs_create_blob_bs_dev(struct spdk_blob *blob)
{
struct spdk_blob_bs_dev *b;
b = calloc(1, sizeof(*b));
if (b == NULL) {
return NULL;
}
/* snapshot blob */
b->bs_dev.blockcnt = blob->active.num_clusters *
blob->bs->pages_per_cluster * bs_io_unit_per_page(blob->bs);
b->bs_dev.blocklen = spdk_bs_get_io_unit_size(blob->bs);
b->bs_dev.create_channel = NULL;
b->bs_dev.destroy_channel = NULL;
b->bs_dev.destroy = blob_bs_dev_destroy;
b->bs_dev.write = blob_bs_dev_write;
b->bs_dev.writev = blob_bs_dev_writev;
b->bs_dev.writev_ext = blob_bs_dev_writev_ext;
b->bs_dev.read = blob_bs_dev_read;
b->bs_dev.readv = blob_bs_dev_readv;
b->bs_dev.readv_ext = blob_bs_dev_readv_ext;
b->bs_dev.write_zeroes = blob_bs_dev_write_zeroes;
b->bs_dev.unmap = blob_bs_dev_unmap;
b->bs_dev.is_zeroes = blob_bs_is_zeroes;
b->blob = blob;
return &b->bs_dev;
}