Commit c69529d4 authored by Konrad Sztyber's avatar Konrad Sztyber Committed by Ben Walker
Browse files

lib/ftl: block nv_cache until header is written 



After filling whole non-volatile cache, block all further writes until
the header with metadata is written. This means that metadata stored on
the device will always be up-to-date with the most recent write
sequence.

Change-Id: I15b724b52814289622374ce77e5c3b23173a75c6
Signed-off-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/458097


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@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>
Reviewed-by: default avatarWojciech Malikowski <wojciech.malikowski@intel.com>
parent 2c967455

lib/ftl/ftl_core.c

+50 −1
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ 
#include "spdk/string.h"

#include "spdk_internal/log.h"

#include "spdk/ftl.h"

#include "spdk/crc32.h"



#include "ftl_core.h"

#include "ftl_band.h"
@@ -944,6 +945,52 @@ ftl_process_flush(struct spdk_ftl_dev *dev, struct ftl_rwb_batch *batch) 
	}

}



static void

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

{

	struct ftl_nv_cache *nv_cache = cb_arg;



	if (!success) {

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

		/* TODO: go into read-only mode */

		assert(0);

	}



	pthread_spin_lock(&nv_cache->lock);

	nv_cache->ready = true;

	pthread_spin_unlock(&nv_cache->lock);



	spdk_bdev_free_io(bdev_io);

}



static void

ftl_nv_cache_wrap(void *ctx)

{

	struct spdk_ftl_dev *dev = ctx;

	struct ftl_nv_cache *nv_cache = &dev->nv_cache;

	struct ftl_nv_cache_header *hdr = nv_cache->dma_buf;

	struct ftl_io_channel *ioch;

	struct spdk_bdev *bdev;

	int rc;



	ioch = spdk_io_channel_get_ctx(dev->ioch);

	bdev = spdk_bdev_desc_get_bdev(nv_cache->bdev_desc);



	hdr->uuid = dev->uuid;

	hdr->size = spdk_bdev_get_num_blocks(bdev);

	hdr->version = FTL_NV_CACHE_HEADER_VERSION;

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



	rc = spdk_bdev_write_blocks(nv_cache->bdev_desc, ioch->cache_ioch, hdr, 0, 1,

				    ftl_nv_cache_wrap_cb, nv_cache);

	if (spdk_unlikely(rc != 0)) {

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

			    spdk_strerror(-rc));

		/* TODO: go into read-only mode */

		assert(0);

	}

}



static uint64_t

ftl_reserve_nv_cache(struct ftl_nv_cache *nv_cache, size_t *num_lbks)

{
@@ -954,7 +1001,7 @@ ftl_reserve_nv_cache(struct ftl_nv_cache *nv_cache, size_t *num_lbks) 
	cache_size = spdk_bdev_get_num_blocks(bdev);



	pthread_spin_lock(&nv_cache->lock);

	if (spdk_unlikely(nv_cache->num_available == 0)) {

	if (spdk_unlikely(nv_cache->num_available == 0 || !nv_cache->ready)) {

		goto out;

	}
@@ -973,6 +1020,8 @@ ftl_reserve_nv_cache(struct ftl_nv_cache *nv_cache, size_t *num_lbks) 


	if (nv_cache->current_addr == spdk_bdev_get_num_blocks(bdev)) {

		nv_cache->current_addr = FTL_NV_CACHE_DATA_OFFSET;

		nv_cache->ready = false;

		spdk_thread_send_msg(ftl_get_core_thread(dev), ftl_nv_cache_wrap, dev);

	}

out:

	pthread_spin_unlock(&nv_cache->lock);

lib/ftl/ftl_core.h

+4 −0
Original line number Diff line number Diff line
@@ -112,8 +112,12 @@ struct ftl_nv_cache { 
	uint64_t				num_available;

	/* Maximum number of blocks */

	uint64_t				num_data_blocks;

	/* Indicates that the data can be written to the cache */

	bool					ready;

	/* Metadata pool */

	struct spdk_mempool			*md_pool;

	/* DMA buffer for writing the header */

	void					*dma_buf;

	/* Cache lock */

	pthread_spinlock_t			lock;

};

lib/ftl/ftl_init.c

+10 −0
Original line number Diff line number Diff line
@@ -557,6 +557,12 @@ ftl_dev_init_nv_cache(struct spdk_ftl_dev *dev, struct spdk_bdev_desc *bdev_desc 
		return -1;

	}



	nv_cache->dma_buf = spdk_dma_zmalloc(FTL_BLOCK_SIZE, spdk_bdev_get_buf_align(bdev), NULL);

	if (!nv_cache->dma_buf) {

		SPDK_ERRLOG("Memory allocation failure\n");

		return -1;

	}



	if (pthread_spin_init(&nv_cache->lock, PTHREAD_PROCESS_PRIVATE)) {

		SPDK_ERRLOG("Failed to initialize cache lock\n");

		return -1;
@@ -566,6 +572,7 @@ ftl_dev_init_nv_cache(struct spdk_ftl_dev *dev, struct spdk_bdev_desc *bdev_desc 
	nv_cache->current_addr = FTL_NV_CACHE_DATA_OFFSET;

	nv_cache->num_data_blocks = spdk_bdev_get_num_blocks(bdev) - 1;

	nv_cache->num_available = nv_cache->num_data_blocks;

	nv_cache->ready = false;



	return 0;

}
@@ -867,6 +874,7 @@ ftl_write_nv_cache_md_cb(struct spdk_bdev_io *bdev_io, bool success, void *cb_ar 
		return;

	}



	dev->nv_cache.ready = true;

	ftl_init_complete(dev);

}
@@ -1236,6 +1244,8 @@ ftl_dev_free_sync(struct spdk_ftl_dev *dev) 
		}

	}



	spdk_dma_free(dev->nv_cache.dma_buf);



	spdk_mempool_free(dev->lba_pool);

	spdk_mempool_free(dev->nv_cache.md_pool);

	if (dev->lba_request_pool) {

lib/ftl/ftl_restore.c

+4 −0
Original line number Diff line number Diff line
@@ -421,6 +421,10 @@ ftl_nv_cache_header_cb(struct spdk_bdev_io *bdev_io, bool success, void *cb_arg) 
		rc = -ENOTRECOVERABLE;

		goto out;

	}



	pthread_spin_lock(&nv_cache->lock);

	nv_cache->ready = true;

	pthread_spin_unlock(&nv_cache->lock);

out:

	ftl_restore_complete(restore, rc);

	spdk_bdev_free_io(bdev_io);