Re: [dpdk-dev] [PATCH v9 2/5] kni: add IOVA=VA support in KNI lib

[Igor Ryzhov <iryzhov@nfware.com>]

Hi,

I believe iova_mode check should not be automatic and should be a part
of rte_kni_conf.
What if I want to use KNI just as a pure virtual device without any
connection to a real PCI device in an application that works in VA
mode?

Best regards,
Igor

On Mon, Jul 29, 2019 at 3:14 PM <vattunuru@marvell.com> wrote:
>
> From: Vamsi Attunuru <vattunuru@marvell.com>
>
> Current KNI implementation only operates in IOVA=PA mode, patch adds
> required functionality in KNI lib to support IOVA=VA mode.
>
> KNI kernel module requires device info to get iommu domain related
> information for IOVA addr related translations. Patch defines device
> related info in rte_kni_device_info structure and passes device info
> to the kernel KNI module when IOVA=VA mode is enabled.
>
> Signed-off-by: Vamsi Attunuru <vattunuru@marvell.com>
> Signed-off-by: Kiran Kumar K <kirankumark@marvell.com>
> ---
>  lib/librte_eal/linux/eal/include/rte_kni_common.h |  8 ++++++
>  lib/librte_kni/Makefile                           |  1 +
>  lib/librte_kni/meson.build                        |  1 +
>  lib/librte_kni/rte_kni.c                          | 30 +++++++++++++++++++++++
>  4 files changed, 40 insertions(+)
>
> diff --git a/lib/librte_eal/linux/eal/include/rte_kni_common.h b/lib/librte_eal/linux/eal/include/rte_kni_common.h
> index 37d9ee8..4fd8a90 100644
> --- a/lib/librte_eal/linux/eal/include/rte_kni_common.h
> +++ b/lib/librte_eal/linux/eal/include/rte_kni_common.h
> @@ -111,6 +111,13 @@ struct rte_kni_device_info {
>         void * mbuf_va;
>         phys_addr_t mbuf_phys;
>
> +       /* PCI info */
> +       uint16_t vendor_id;           /**< Vendor ID or PCI_ANY_ID. */
> +       uint16_t device_id;           /**< Device ID or PCI_ANY_ID. */
> +       uint8_t bus;                  /**< Device bus */
> +       uint8_t devid;                /**< Device ID */
> +       uint8_t function;             /**< Device function. */
> +
>         uint16_t group_id;            /**< Group ID */
>         uint32_t core_id;             /**< core ID to bind for kernel thread */
>
> @@ -121,6 +128,7 @@ struct rte_kni_device_info {
>         unsigned mbuf_size;
>         unsigned int mtu;
>         uint8_t mac_addr[6];
> +       uint8_t iova_mode;
>  };
>
>  #define KNI_DEVICE "kni"
> diff --git a/lib/librte_kni/Makefile b/lib/librte_kni/Makefile
> index cbd6599..ab15d10 100644
> --- a/lib/librte_kni/Makefile
> +++ b/lib/librte_kni/Makefile
> @@ -7,6 +7,7 @@ include $(RTE_SDK)/mk/rte.vars.mk
>  LIB = librte_kni.a
>
>  CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR) -O3 -fno-strict-aliasing
> +CFLAGS += -I$(RTE_SDK)/drivers/bus/pci
>  LDLIBS += -lrte_eal -lrte_mempool -lrte_mbuf -lrte_ethdev
>
>  EXPORT_MAP := rte_kni_version.map
> diff --git a/lib/librte_kni/meson.build b/lib/librte_kni/meson.build
> index 41fa2e3..fd46f87 100644
> --- a/lib/librte_kni/meson.build
> +++ b/lib/librte_kni/meson.build
> @@ -9,3 +9,4 @@ version = 2
>  sources = files('rte_kni.c')
>  headers = files('rte_kni.h')
>  deps += ['ethdev', 'pci']
> +includes += include_directories('../../drivers/bus/pci')
> diff --git a/lib/librte_kni/rte_kni.c b/lib/librte_kni/rte_kni.c
> index 4b51fb4..2aaaeaa 100644
> --- a/lib/librte_kni/rte_kni.c
> +++ b/lib/librte_kni/rte_kni.c
> @@ -14,6 +14,7 @@
>  #include <rte_spinlock.h>
>  #include <rte_string_fns.h>
>  #include <rte_ethdev.h>
> +#include <rte_bus_pci.h>
>  #include <rte_malloc.h>
>  #include <rte_log.h>
>  #include <rte_kni.h>
> @@ -199,6 +200,27 @@ kni_release_mz(struct rte_kni *kni)
>         rte_memzone_free(kni->m_sync_addr);
>  }
>
> +static void
> +kni_dev_pci_addr_get(uint16_t port_id, struct rte_kni_device_info *kni_dev_info)
> +{
> +       const struct rte_pci_device *pci_dev;
> +       struct rte_eth_dev_info dev_info;
> +       const struct rte_bus *bus = NULL;
> +
> +       rte_eth_dev_info_get(port_id, &dev_info);
> +
> +       if (dev_info.device)
> +               bus = rte_bus_find_by_device(dev_info.device);
> +       if (bus && !strcmp(bus->name, "pci")) {
> +               pci_dev = RTE_DEV_TO_PCI(dev_info.device);
> +               kni_dev_info->bus = pci_dev->addr.bus;
> +               kni_dev_info->devid = pci_dev->addr.devid;
> +               kni_dev_info->function = pci_dev->addr.function;
> +               kni_dev_info->vendor_id = pci_dev->id.vendor_id;
> +               kni_dev_info->device_id = pci_dev->id.device_id;
> +       }
> +}
> +
>  struct rte_kni *
>  rte_kni_alloc(struct rte_mempool *pktmbuf_pool,
>               const struct rte_kni_conf *conf,
> @@ -247,6 +269,12 @@ rte_kni_alloc(struct rte_mempool *pktmbuf_pool,
>                 kni->ops.port_id = UINT16_MAX;
>
>         memset(&dev_info, 0, sizeof(dev_info));
> +
> +       if (rte_eal_iova_mode() == RTE_IOVA_VA) {
> +               uint16_t port_id = conf->group_id;
> +
> +               kni_dev_pci_addr_get(port_id, &dev_info);
> +       }
>         dev_info.core_id = conf->core_id;
>         dev_info.force_bind = conf->force_bind;
>         dev_info.group_id = conf->group_id;
> @@ -300,6 +328,8 @@ rte_kni_alloc(struct rte_mempool *pktmbuf_pool,
>         kni->group_id = conf->group_id;
>         kni->mbuf_size = conf->mbuf_size;
>
> +       dev_info.iova_mode = (rte_eal_iova_mode() == RTE_IOVA_VA) ? 1 : 0;
> +
>         ret = ioctl(kni_fd, RTE_KNI_IOCTL_CREATE, &dev_info);
>         if (ret < 0)
>                 goto ioctl_fail;
> --
> 2.8.4
>