Commit 77ddc70e authored by Konrad Sztyber's avatar Konrad Sztyber Committed by Ben Walker
Browse files

lib/ftl: restore non-volatile cache's metadata 



When restoring the device, read the first block of the non-volatile
cache containing its metadata header and verify that it's indeed a
device that was used as write cache.

Change-Id: Idf113a9e8eb73160a2d9e6e882c9e026d3fafb3e
Signed-off-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/458095


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarMateusz Kozlowski <mateusz.kozlowski@intel.com>
Reviewed-by: default avatarDarek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
parent 1243c930

lib/ftl/ftl_restore.c

+91 −2
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ 
#include "spdk/util.h"

#include "spdk/likely.h"

#include "spdk/string.h"

#include "spdk/crc32.h"



#include "ftl_core.h"

#include "ftl_band.h"
@@ -371,6 +372,91 @@ ftl_restore_next_band(struct ftl_restore *restore) 
	return NULL;

}



static void

ftl_nv_cache_header_cb(struct spdk_bdev_io *bdev_io, bool success, void *cb_arg)

{

	struct ftl_restore *restore = cb_arg;

	struct spdk_ftl_dev *dev = restore->dev;

	struct spdk_bdev *bdev;

	struct ftl_nv_cache *nv_cache = &dev->nv_cache;

	struct ftl_nv_cache_header *hdr;

	struct iovec *iov = NULL;

	int rc = 0, iov_cnt = 0;

	uint32_t checksum;



	bdev = spdk_bdev_desc_get_bdev(nv_cache->bdev_desc);

	spdk_bdev_io_get_iovec(bdev_io, &iov, &iov_cnt);

	hdr = iov[0].iov_base;



	if (!success) {

		SPDK_ERRLOG("Unable to read non-volatile cache metadata header\n");

		rc = -ENOTRECOVERABLE;

		goto out;

	}



	checksum = spdk_crc32c_update(hdr, offsetof(struct ftl_nv_cache_header, checksum), 0);

	if (checksum != hdr->checksum) {

		SPDK_ERRLOG("Invalid header checksum (found: %"PRIu32", expected: %"PRIu32")\n",

			    checksum, hdr->checksum);

		rc = -ENOTRECOVERABLE;

		goto out;

	}



	if (hdr->version != FTL_NV_CACHE_HEADER_VERSION) {

		SPDK_ERRLOG("Invalid header version (found: %"PRIu32", expected: %"PRIu32")\n",

			    hdr->version, FTL_NV_CACHE_HEADER_VERSION);

		rc = -ENOTRECOVERABLE;

		goto out;

	}



	if (hdr->size != spdk_bdev_get_num_blocks(bdev)) {

		SPDK_ERRLOG("Unexpected size of the non-volatile cache bdev (%"PRIu64", expected: %"

			    PRIu64")\n", hdr->size, spdk_bdev_get_num_blocks(bdev));

		rc = -ENOTRECOVERABLE;

		goto out;

	}



	if (spdk_uuid_compare(&hdr->uuid, &dev->uuid)) {

		SPDK_ERRLOG("Invalid device UUID\n");

		rc = -ENOTRECOVERABLE;

		goto out;

	}

out:

	ftl_restore_complete(restore, rc);

	spdk_bdev_free_io(bdev_io);

	spdk_dma_free(hdr);

}



static void

ftl_restore_nv_cache(struct ftl_restore *restore)

{

	struct spdk_ftl_dev *dev = restore->dev;

	struct spdk_bdev *bdev;

	struct ftl_nv_cache *nv_cache = &dev->nv_cache;

	struct ftl_io_channel *ioch;

	void *buf;

	int rc;



	ioch = spdk_io_channel_get_ctx(dev->ioch);

	bdev = spdk_bdev_desc_get_bdev(nv_cache->bdev_desc);



	buf = spdk_dma_zmalloc(spdk_bdev_get_block_size(bdev), spdk_bdev_get_buf_align(bdev), NULL);

	if (spdk_unlikely(!buf)) {

		SPDK_ERRLOG("Memory allocation failure\n");

		ftl_restore_complete(restore, -ENOMEM);

		return;

	}



	rc = spdk_bdev_read_blocks(nv_cache->bdev_desc, ioch->cache_ioch, buf, 0, 1,

				   ftl_nv_cache_header_cb, restore);

	if (spdk_unlikely(rc != 0)) {

		SPDK_ERRLOG("Failed to read non-volatile cache metadata header: %s\n",

			    spdk_strerror(-rc));

		ftl_restore_complete(restore, rc);

		spdk_dma_free(buf);

	}

}



static bool

ftl_pad_chunk_pad_finish(struct ftl_restore_band *rband, bool direct_access)

{
@@ -572,7 +658,7 @@ ftl_restore_tail_md_cb(struct ftl_io *io, void *ctx, int status) 
{

	struct ftl_restore_band *rband = ctx;

	struct ftl_restore *restore = rband->parent;

	struct spdk_ftl_dev *dev = rband->band->dev;

	struct spdk_ftl_dev *dev = restore->dev;



	if (status) {

		if (!dev->conf.allow_open_bands) {
@@ -604,9 +690,12 @@ ftl_restore_tail_md_cb(struct ftl_io *io, void *ctx, int status) 
		if (!STAILQ_EMPTY(&restore->pad_bands)) {

			spdk_thread_send_msg(ftl_get_core_thread(dev), ftl_restore_pad_open_bands,

					     restore);

		} else if (dev->nv_cache.bdev_desc) {

			ftl_restore_nv_cache(restore);

		} else {

			ftl_restore_complete(restore, status);

			ftl_restore_complete(restore, 0);

		}



		return;

	}