Function l2arc_read_done

freebsd/contrib/openzfs/module/zfs/arc.c:8467–8604

* A read to a cache device completed. Validate buffer contents before * handing over to the regular ARC routines. */

 * handing over to the regular ARC routines.
 */
static void
l2arc_read_done(zio_t *zio)
{
	int tfm_error = 0;
	l2arc_read_callback_t *cb = zio->io_private;
	arc_buf_hdr_t *hdr;
	kmutex_t *hash_lock;
	boolean_t valid_cksum;
	boolean_t using_rdata = (BP_IS_ENCRYPTED(&cb->l2rcb_bp) &&
	    (cb->l2rcb_flags & ZIO_FLAG_RAW_ENCRYPT));

	ASSERT3P(zio->io_vd, !=, NULL);
	ASSERT(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE);

	spa_config_exit(zio->io_spa, SCL_L2ARC, zio->io_vd);

	ASSERT3P(cb, !=, NULL);
	hdr = cb->l2rcb_hdr;
	ASSERT3P(hdr, !=, NULL);

	hash_lock = HDR_LOCK(hdr);
	mutex_enter(hash_lock);
	ASSERT3P(hash_lock, ==, HDR_LOCK(hdr));

	/*
	 * If the data was read into a temporary buffer,
	 * move it and free the buffer.
	 */
	if (cb->l2rcb_abd != NULL) {
		ASSERT3U(arc_hdr_size(hdr), <, zio->io_size);
		if (zio->io_error == 0) {
			if (using_rdata) {
				abd_copy(hdr->b_crypt_hdr.b_rabd,
				    cb->l2rcb_abd, arc_hdr_size(hdr));
			} else {
				abd_copy(hdr->b_l1hdr.b_pabd,
				    cb->l2rcb_abd, arc_hdr_size(hdr));
			}
		}

		/*
		 * The following must be done regardless of whether
		 * there was an error:
		 * - free the temporary buffer
		 * - point zio to the real ARC buffer
		 * - set zio size accordingly
		 * These are required because zio is either re-used for
		 * an I/O of the block in the case of the error
		 * or the zio is passed to arc_read_done() and it
		 * needs real data.
		 */
		abd_free(cb->l2rcb_abd);
		zio->io_size = zio->io_orig_size = arc_hdr_size(hdr);

		if (using_rdata) {
			ASSERT(HDR_HAS_RABD(hdr));
			zio->io_abd = zio->io_orig_abd =
			    hdr->b_crypt_hdr.b_rabd;