On Wed, Oct 05, 2016 at 03:30:42AM +0000, Gonglei (Arei) wrote: > > > -----Original Message----- > > From: virtio-...@lists.oasis-open.org > > [mailto:virtio-...@lists.oasis-open.org] > > On Behalf Of Stefan Hajnoczi > > Sent: Tuesday, October 04, 2016 5:46 PM > > Subject: [virtio-dev] Re: [PATCH v4 07/13] virtio-crypto: set capacity of > > algorithms supported > > > > On Wed, Sep 28, 2016 at 04:25:46PM +0800, Gonglei wrote: > > > static void virtio_crypto_get_config(VirtIODevice *vdev, uint8_t *config) > > > { > > > - > > > + VirtIOCrypto *c = VIRTIO_CRYPTO(vdev); > > > + struct virtio_crypto_config crypto_cfg; > > > + > > > + crypto_cfg.status = c->status; > > > + crypto_cfg.max_dataqueues = c->max_queues; > > > + crypto_cfg.crypto_services = c->conf.crypto_services; > > > + crypto_cfg.cipher_algo_l = c->conf.cipher_algo_l; > > > + crypto_cfg.cipher_algo_h = c->conf.cipher_algo_h; > > > + crypto_cfg.hash_algo = c->conf.hash_algo; > > > + crypto_cfg.mac_algo_l = c->conf.mac_algo_l; > > > + crypto_cfg.mac_algo_h = c->conf.mac_algo_h; > > > + crypto_cfg.aead_algo = c->conf.aead_algo; > > > + > > > + memcpy(config, &crypto_cfg, c->config_size); > > > } > > > > What about endianness? For example, if the host is big-endian then this > > VIRTIO 1.0 device needs to byteswap multi-byte fields. There is a > > family of functions to help with this: virtio_stl_p(). > > I did that in v1. Michael told me that Virtio-1.0 devices are always > little-endian, so > I removed those helper functions in the following functions. But after this > version, > the virtio-crypto device isn't virtio-1.0 device by default, so I should use > them again.
Endian awareness is still necessary for VIRTIO 1.0-only devices. The uint8_t *config data is just a blob. Therefore nothing automatically handles little-endian conversion for us. We *must* read little-endian from config[].
signature.asc
Description: PGP signature
