blob: Add support for crc of super block.

Change-Id: I424833a0af6e5e8265c03c168b9dfdbae1a49cd8
Signed-off-by: Cunyin Chang <cunyin.chang@intel.com>
Reviewed-on: https://review.gerrithub.io/378233
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

doc/blob.md

@@ -176,7 +176,7 @@ It contains basic information about the blobstore. The metadata region
 is the remainder of cluster 0 and may extend to additional clusters.
 
     <super-block> ::= <sb-version> <sb-len> <sb-super-blob> <sb-params>
-                      <sb-metadata-start> <sb-metadata-len>
+                      <sb-metadata-start> <sb-metadata-len> <crc>
     <sb-version> ::= u32
     <sb-len> ::= u32 # Length of this super block, in bytes. Starts from the
                      # beginning of this structure.
@@ -185,6 +185,7 @@ is the remainder of cluster 0 and may extend to additional clusters.
 
     <sb-md-start> ::= u64 # Metadata start location, in pages
     <sb-md-len> ::= u64 # Metadata length, in pages
+    <crc> ::= u32 # Crc for super block
 
 The `<sb-params>` data contains parameters specified by the user when the blob
 store was initially formatted.

lib/blob/blobstore.c

@@ -1548,6 +1548,7 @@ static void
 _spdk_bs_load_super_cpl(spdk_bs_sequence_t *seq, void *cb_arg, int bserrno)
 {
 	struct spdk_bs_load_ctx *ctx = cb_arg;
+	uint32_t	crc;
 
 	if (ctx->super->version != SPDK_BS_VERSION) {
 		spdk_dma_free(ctx->super);
@@ -1566,6 +1567,15 @@ _spdk_bs_load_super_cpl(spdk_bs_sequence_t *seq, void *cb_arg, int bserrno)
 		return;
 	}
 
+	crc = _spdk_blob_md_page_calc_crc(ctx->super);
+	if (crc != ctx->super->crc) {
+		spdk_dma_free(ctx->super);
+		_spdk_bs_free(ctx->bs);
+		free(ctx);
+		spdk_bs_sequence_finish(seq, -EILSEQ);
+		return;
+	}
+
 	if (ctx->super->clean != 1) {
 		/* TODO: ONLY CLEAN SHUTDOWN IS CURRENTLY SUPPORTED.
 		 * All of the necessary data to recover is available
@@ -1580,7 +1590,7 @@ _spdk_bs_load_super_cpl(spdk_bs_sequence_t *seq, void *cb_arg, int bserrno)
 	}
 
 	ctx->super->clean = 0;
-
+	ctx->super->crc = _spdk_blob_md_page_calc_crc(ctx->super);
 	spdk_bs_sequence_write(seq, ctx->super, _spdk_bs_page_to_lba(ctx->bs, 0),
 			       _spdk_bs_byte_to_lba(ctx->bs, sizeof(*ctx->super)),
 			       _spdk_bs_load_write_super_cpl, ctx);
@@ -1781,6 +1791,7 @@ spdk_bs_init(struct spdk_bs_dev *dev, struct spdk_bs_opts *o,
 	ctx->super->md_len = bs->md_len;
 	num_md_pages += bs->md_len;
 
+	ctx->super->crc = _spdk_blob_md_page_calc_crc(ctx->super);
 	/* Claim all of the clusters used by the metadata */
 	for (i = 0; i < divide_round_up(num_md_pages, bs->pages_per_cluster); i++) {
 		_spdk_bs_claim_cluster(bs, i);
@@ -1838,7 +1849,7 @@ _spdk_bs_unload_write_used_clusters_cpl(spdk_bs_sequence_t *seq, void *cb_arg, i
 	/* Update the values in the super block */
 	ctx->super->super_blob = ctx->bs->super_blob;
 	ctx->super->clean = 1;
-
+	ctx->super->crc = _spdk_blob_md_page_calc_crc(ctx->super);
 	spdk_bs_sequence_write(seq, ctx->super, _spdk_bs_page_to_lba(ctx->bs, 0),
 			       _spdk_bs_byte_to_lba(ctx->bs, sizeof(*ctx->super)),
 			       _spdk_bs_unload_write_super_cpl, ctx);

lib/blob/blobstore.h

@@ -253,7 +253,8 @@ struct spdk_bs_super_block {
 	uint32_t	md_start; /* Offset from beginning of disk, in pages */
 	uint32_t	md_len; /* Count, in pages */
 
-	uint8_t		reserved[4040];
+	uint8_t		reserved[4036];
+	uint32_t	crc;
 };
 SPDK_STATIC_ASSERT(sizeof(struct spdk_bs_super_block) == 0x1000, "Invalid super block size");
 

test/unit/lib/blob/blob.c/blob_ut.c

@@ -1234,6 +1234,37 @@ blob_crc(void)
 	g_bs = NULL;
 }
 
+static void
+super_block_crc(void)
+{
+	struct spdk_bs_dev *dev;
+	struct spdk_bs_super_block *super_block;
+
+	dev = init_dev();
+
+	spdk_bs_init(dev, NULL, bs_op_with_handle_complete, NULL);
+	CU_ASSERT(g_bserrno == 0);
+	SPDK_CU_ASSERT_FATAL(g_bs != NULL);
+
+	spdk_bs_unload(g_bs, bs_op_complete, NULL);
+	CU_ASSERT(g_bserrno == 0);
+	g_bs = NULL;
+
+	super_block = (struct spdk_bs_super_block *)g_dev_buffer;
+	super_block->crc = 0;
+	dev = init_dev();
+
+	g_scheduler_delay = true;
+	/* Load an existing blob store */
+	spdk_bs_load(dev, bs_op_with_handle_complete, NULL);
+
+	CU_ASSERT(g_bserrno == -EILSEQ);
+	_bs_flush_scheduler();
+	CU_ASSERT(TAILQ_EMPTY(&g_scheduled_ops));
+
+	g_scheduler_delay = false;
+}
+
 int main(int argc, char **argv)
 {
 	CU_pSuite	suite = NULL;
@@ -1268,7 +1299,8 @@ int main(int argc, char **argv)
 		CU_add_test(suite, "bs_cluster_sz", bs_cluster_sz) == NULL ||
 		CU_add_test(suite, "bs_resize_md", bs_resize_md) == NULL ||
 		CU_add_test(suite, "blob_serialize", blob_serialize) == NULL ||
-		CU_add_test(suite, "blob_crc", blob_crc) == NULL
+		CU_add_test(suite, "blob_crc", blob_crc) == NULL ||
+		CU_add_test(suite, "super_block_crc", super_block_crc) == NULL
 	) {
 		CU_cleanup_registry();
 		return CU_get_error();