Commit 07042bde authored Mar 15, 2019 by Darek Stojaczyk Committed by Jim Harris Mar 18, 2019

env/dpdk: remove the fake rte_bus



This practically reverts commit 2fe7aa5e [1].

The extra rte_bus was supposed to allow running SPDK
as a non-priviledged user by enabling RTE_IOVA_VA mode.
DPDK uses RTE_IOVA_PA by default - which means there are
physical addresses used as memseg IOVAs and hence the
root access is required to retrieve those physical
addresses. This patch was supposed to be paired with
a different DPDK patch of mine, but DPDK rejected that
one. Instead, in DPDK 18.11+ the user can force iova mode
by specifying --iova-mode=<mode> command line option,
where <mode> is either pa or va.

Either way, apparently there are cases where physical
address contiguity is required even without UIO (#707)
so let's revert this patch and consistently stick with
RTE_IOVA_PA.

SPDK requires some more effort to support running as
a non-priviledged user anyway.

Fixes #707

[1] env_dpdk/vtophys: register a fake rte_bus supporting RTE_IOVA_VA

Change-Id: I90bf097fd6a7f129444229dc7cf07a462d4f2d09
Signed-off-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/448121


Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>

parent ac2dd4b2

lib/env_dpdk/memory.c

+0 −46

Original line number	Diff line number	Diff line
		@@ -1345,49 +1345,3 @@ spdk_vtophys(void buf, uint64_t size)
		return paddr_2mb + (vaddr & MASK_2MB);
		}
		}

		static int
		spdk_bus_scan(void)
		{
		return 0;
		}

		static int
		spdk_bus_probe(void)
		{
		return 0;
		}

		static struct rte_device *
		spdk_bus_find_device(const struct rte_device *start,
		rte_dev_cmp_t cmp, const void *data)
		{
		return NULL;
		}

		#if RTE_VERSION >= RTE_VERSION_NUM(17, 11, 0, 3)
		static enum rte_iova_mode
		spdk_bus_get_iommu_class(void) {
		/* Since we register our PCI drivers after EAL init, we have no chance
		* of switching into RTE_IOVA_VA (virtual addresses as iova) iommu
		* class. DPDK uses RTE_IOVA_PA by default because for some platforms
		* it's the only supported mode, but then SPDK does not support those
		* platforms and doesn't mind defaulting to RTE_IOVA_VA. The rte_pci bus
		* will force RTE_IOVA_PA if RTE_IOVA_VA simply can not be used
		* (i.e. at least one device on the system is bound to uio_pci_generic),
		* so we simply return RTE_IOVA_VA here.
		*/
		return RTE_IOVA_VA;
		}
		#endif

		struct rte_bus spdk_bus = {
		.scan = spdk_bus_scan,
		.probe = spdk_bus_probe,
		.find_device = spdk_bus_find_device,
		#if RTE_VERSION >= RTE_VERSION_NUM(17, 11, 0, 3)
		.get_iommu_class = spdk_bus_get_iommu_class,
		#endif
		};

		RTE_REGISTER_BUS(spdk, spdk_bus);