blk-mq: avoid stall during boot due to synchronize_rcu_expedited

Documentation/block/inline-encryption.rst

@@ -206,6 +206,12 @@ it to a bio, given the blk_crypto_key and the data unit number that will be used
 for en/decryption.  Users don't need to worry about freeing the bio_crypt_ctx
 later, as that happens automatically when the bio is freed or reset.
 
+To submit a bio that uses inline encryption, users must call
+``blk_crypto_submit_bio()`` instead of the usual ``submit_bio()``.  This will
+submit the bio to the underlying driver if it supports inline crypto, or else
+call the blk-crypto fallback routines before submitting normal bios to the
+underlying drivers.
+
 Finally, when done using inline encryption with a blk_crypto_key on a
 block_device, users must call ``blk_crypto_evict_key()``.  This ensures that
 the key is evicted from all keyslots it may be programmed into and unlinked from

block/bio-integrity-auto.c

@@ -52,19 +52,7 @@ static bool bip_should_check(struct bio_integrity_payload *bip)
 
 static bool bi_offload_capable(struct blk_integrity *bi)
 {
-	switch (bi->csum_type) {
-	case BLK_INTEGRITY_CSUM_CRC64:
-		return bi->metadata_size == sizeof(struct crc64_pi_tuple);
-	case BLK_INTEGRITY_CSUM_CRC:
-	case BLK_INTEGRITY_CSUM_IP:
-		return bi->metadata_size == sizeof(struct t10_pi_tuple);
-	default:
-		pr_warn_once("%s: unknown integrity checksum type:%d\n",
-			__func__, bi->csum_type);
-		fallthrough;
-	case BLK_INTEGRITY_CSUM_NONE:
-		return false;
-	}
+	return bi->metadata_size == bi->pi_tuple_size;
 }
 
 /**
@@ -140,7 +128,7 @@ bool bio_integrity_prep(struct bio *bio)
 				return true;
 			set_flags = false;
 			gfp |= __GFP_ZERO;
-		} else if (bi->csum_type == BLK_INTEGRITY_CSUM_NONE)
+		} else if (bi->metadata_size > bi->pi_tuple_size)
 			gfp |= __GFP_ZERO;
 		break;
 	default:

block/bio.c

@@ -301,9 +301,12 @@ EXPORT_SYMBOL(bio_init);
  */
 void bio_reset(struct bio *bio, struct block_device *bdev, blk_opf_t opf)
 {
+	struct bio_vec          *bv = bio->bi_io_vec;
+
 	bio_uninit(bio);
 	memset(bio, 0, BIO_RESET_BYTES);
 	atomic_set(&bio->__bi_remaining, 1);
+	bio->bi_io_vec = bv;
 	bio->bi_bdev = bdev;
 	if (bio->bi_bdev)
 		bio_associate_blkg(bio);
@@ -1162,8 +1165,8 @@ void bio_iov_bvec_set(struct bio *bio, const struct iov_iter *iter)
 {
 	WARN_ON_ONCE(bio->bi_max_vecs);
 
-	bio->bi_vcnt = iter->nr_segs;
 	bio->bi_io_vec = (struct bio_vec *)iter->bvec;
+	bio->bi_iter.bi_idx = 0;
 	bio->bi_iter.bi_bvec_done = iter->iov_offset;
 	bio->bi_iter.bi_size = iov_iter_count(iter);
 	bio_set_flag(bio, BIO_CLONED);

block/blk-core.c

@@ -628,9 +628,6 @@ static void __submit_bio(struct bio *bio)
 	/* If plug is not used, add new plug here to cache nsecs time. */
 	struct blk_plug plug;
 
-	if (unlikely(!blk_crypto_bio_prep(&bio)))
-		return;
-
 	blk_start_plug(&plug);
 
 	if (!bdev_test_flag(bio->bi_bdev, BD_HAS_SUBMIT_BIO)) {
@@ -794,6 +791,13 @@ void submit_bio_noacct(struct bio *bio)
 	if ((bio->bi_opf & REQ_NOWAIT) && !bdev_nowait(bdev))
 		goto not_supported;
 
+	if (bio_has_crypt_ctx(bio)) {
+		if (WARN_ON_ONCE(!bio_has_data(bio)))
+			goto end_io;
+		if (!blk_crypto_supported(bio))
+			goto not_supported;
+	}
+
 	if (should_fail_bio(bio))
 		goto end_io;
 	bio_check_ro(bio);