ftl: superblock in shared memory

Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Kozlowski Mateusz <mateusz.kozlowski@intel.com>
Change-Id: I86e2cbf364ae3075aad2e09429754027df33eadf
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/13342
Community-CI: Mellanox Build Bot
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>

lib/ftl/ftl_core.h

@@ -47,6 +47,10 @@ struct spdk_ftl_dev {
 	/* FTL superblock */
 	struct ftl_superblock		*sb;
 
+	/* FTL shm superblock */
+	struct ftl_superblock_shm	*sb_shm;
+	struct ftl_md			*sb_shm_md;
+
 	/* Queue of registered IO channels */
 	TAILQ_HEAD(, ftl_io_channel)	ioch_queue;
 
@@ -145,6 +149,9 @@ struct spdk_ftl_dev {
 
 	/* Writer for GC IOs */
 	struct ftl_writer		writer_gc;
+
+	/* Retry init sequence */
+	bool				init_retry;
 };
 
 void ftl_apply_limits(struct spdk_ftl_dev *dev);

lib/ftl/ftl_init.c

@@ -132,8 +132,20 @@ static void
 dev_init_cb(struct spdk_ftl_dev *dev, void *_ctx, int status)
 {
 	struct ftl_dev_init_ctx *ctx = _ctx;
+	int rc;
 
 	if (status) {
+		if (dev->init_retry) {
+			FTL_NOTICELOG(dev, "Startup retry\n");
+			rc = spdk_ftl_dev_init(&dev->conf, ctx->cb_fn, ctx->cb_arg);
+			if (!rc) {
+				free_dev(dev);
+				free(ctx);
+				return;
+			}
+			FTL_NOTICELOG(dev, "Startup retry failed: %d\n", rc);
+		}
+
 		free_dev(dev);
 		dev = NULL;
 	}

lib/ftl/ftl_sb_common.h

@@ -47,4 +47,21 @@ struct ftl_superblock_md_region {
 	uint64_t		blk_sz;
 };
 
+struct ftl_superblock_shm {
+	/* SHM initialization completed */
+	bool				shm_ready;
+
+	/* SHM status - fast restart */
+	bool				shm_clean;
+
+	/* Used to continue trim after SHM recovery */
+	struct {
+		bool			in_progress;
+		uint64_t		start_lba;
+		uint64_t		num_blocks;
+	} trim;
+
+	struct ftl_superblock_gc_info	gc_info;
+};
+
 #endif /* FTL_SB_COMMON_H */

lib/ftl/mngt/ftl_mngt_md.c

@@ -170,6 +170,7 @@ ftl_mngt_init_default_sb(struct spdk_ftl_dev *dev, struct ftl_mngt_process *mngt
 	sb->header.version = FTL_METADATA_VERSION_CURRENT;
 	sb->uuid = dev->conf.uuid;
 	sb->clean = 0;
+	dev->sb_shm->shm_clean = false;
 
 	/* Max 16 IO depth per band relocate */
 	sb->max_reloc_qdepth = 16;
@@ -191,6 +192,7 @@ ftl_mngt_set_dirty(struct spdk_ftl_dev *dev, struct ftl_mngt_process *mngt)
 	struct ftl_superblock *sb = dev->sb;
 
 	sb->clean = 0;
+	dev->sb_shm->shm_clean = false;
 	sb->header.crc = get_sb_crc(sb);
 	persist(dev, mngt, FTL_LAYOUT_REGION_TYPE_SB);
 }
@@ -258,6 +260,18 @@ ftl_mngt_superblock_init(struct spdk_ftl_dev *dev, struct ftl_mngt_process *mngt
 		FTL_NOTICELOG(dev, "Create new FTL, UUID %s\n", uuid);
 	}
 
+	/* Allocate md buf */
+	dev->sb_shm = NULL;
+	dev->sb_shm_md = ftl_md_create(dev, spdk_divide_round_up(sizeof(*dev->sb_shm), FTL_BLOCK_SIZE),
+				       0, "sb_shm",
+				       md_create_flags, NULL);
+	if (dev->sb_shm_md == NULL) {
+		ftl_mngt_fail_step(mngt);
+		return;
+	}
+
+	dev->sb_shm = ftl_md_get_buffer(dev->sb_shm_md);
+
 	/* Setup the layout of a superblock */
 	if (ftl_layout_setup_superblock(dev)) {
 		ftl_mngt_fail_step(mngt);
@@ -308,5 +322,9 @@ ftl_mngt_superblock_deinit(struct spdk_ftl_dev *dev, struct ftl_mngt_process *mn
 		layout->md[FTL_LAYOUT_REGION_TYPE_SB_BASE] = NULL;
 	}
 
+	ftl_md_destroy(dev->sb_shm_md);
+	dev->sb_shm_md = NULL;
+	dev->sb_shm = NULL;
+
 	ftl_mngt_next_step(mngt);
 }

lib/ftl/mngt/ftl_mngt_misc.c

@@ -139,6 +139,7 @@ void
 ftl_mngt_finalize_startup(struct spdk_ftl_dev *dev, struct ftl_mngt_process *mngt)
 {
 	dev->initialized = 1;
+	dev->sb_shm->shm_ready = true;
 
 	ftl_writer_resume(&dev->writer_user);
 	ftl_writer_resume(&dev->writer_gc);

lib/ftl/utils/ftl_md.c

@@ -115,6 +115,15 @@ ftl_md_setup_obj(struct ftl_md *md, int flags,
 	}
 }
 
+static void
+ftl_md_invalidate_shm(struct ftl_md *md)
+{
+	if (md->dev->sb_shm && md->dev->sb_shm->shm_ready) {
+		md->dev->init_retry = true;
+		md->dev->sb_shm->shm_ready = false;
+	}
+}
+
 static void
 ftl_md_create_shm(struct ftl_md *md, uint64_t vss_blksz, int flags)
 {
@@ -138,6 +147,7 @@ ftl_md_create_shm(struct ftl_md *md, uint64_t vss_blksz, int flags)
 	/* If specified, unlink before create a new SHM object */
 	if (flags & FTL_MD_CREATE_SHM_NEW) {
 		if (md->shm_unlink(md->name) < 0 && errno != ENOENT) {
+			ftl_md_invalidate_shm(md);
 			return;
 		}
 		open_flags += O_CREAT | O_TRUNC;
@@ -215,6 +225,7 @@ err_shm:
 		md->shm_unlink(md->name);
 		md->shm_fd = -1;
 	}
+	ftl_md_invalidate_shm(md);
 }
 
 static void