[dpdk-dev] [PATCH v5 08/11] eal: pci: introduce RTE_KDRV_VFIO_NOIOMMUi driver mode
Burakov, Anatoly
anatoly.burakov at intel.com
Tue Jan 19 15:18:00 CET 2016
Hi Santosh,
> +int
> +pci_vfio_is_noiommu(struct rte_pci_device *pci_dev) {
> + FILE *fp;
> + struct rte_pci_addr *loc;
> + const char *path =
> "/sys/module/vfio/parameters/enable_unsafe_noiommu_mode";
> + char filename[PATH_MAX] = {0};
> + char buf[PATH_MAX] = {0};
> +
> + /*
> + * 1. chk vfio-noiommu mode set in kernel driver
> + * 2. verify pci device attached to vfio-noiommu driver
> + * example:
> + * cd /sys/bus/pci/drivers/vfio-pci/<virtio_dev_addr>/iommu_group
> + * > cat name
> + * > vfio-noiommu --> means virtio_dev attached to vfio-noiommu
> driver
> + */
> +
> + fp = fopen(path, "r");
> + if (fp == NULL) {
> + RTE_LOG(ERR, EAL, "can't open %s\n", path);
> + return -1;
> + }
> +
> + if (fread(buf, sizeof(char), 1, fp) != 1) {
> + RTE_LOG(ERR, EAL, "can't read from file %s\n", path);
> + fclose(fp);
> + return -1;
> + }
> +
> + if (strncmp(buf, "Y", 1) != 0) {
> + RTE_LOG(ERR, EAL, "[%s]: vfio: noiommu mode not set\n",
> path);
> + fclose(fp);
> + return -1;
> + }
> +
> + fclose(fp);
> +
> + /* 2. chk whether attached driver is vfio-noiommu or not */
> + loc = &pci_dev->addr;
> + snprintf(filename, sizeof(filename),
> + SYSFS_PCI_DEVICES "/" PCI_PRI_FMT
> "/iommu_group/name",
> + loc->domain, loc->bus, loc->devid, loc->function);
> +
> + /* check for vfio-noiommu */
> + fp = fopen(filename, "r");
> + if (fp == NULL) {
> + RTE_LOG(ERR, EAL, "can't open %s\n", filename);
> + return -1;
> + }
> +
> + if (fread(buf, sizeof(char), sizeof("vfio-noiommu"), fp) !=
> + sizeof("vfio-noiommu")) {
> + RTE_LOG(ERR, EAL, "can't read from file %s\n", filename);
> + fclose(fp);
> + return -1;
> + }
> +
> + if (strncmp(buf, "vfio-noiommu", strlen("vfio-noiommu")) != 0) {
> + RTE_LOG(ERR, EAL, "not a vfio-noiommu driver\n");
> + fclose(fp);
> + return -1;
> + }
> +
> + fclose(fp);
> +
> + return 0;
> +}
Since this is a public non-performance critical API, shouldn't we check if pci_dev is NULL? Otherwise the patch-set seems fine to me as far as VFIO parts are concerned.
Thanks,
Anatoly
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