Commit f4a63bb8 authored by Seth Howell's avatar Seth Howell Committed by Tomasz Zawadzki
Browse files

env_dpdk: keep a memmap refcount of physical addresses 



This allows us to avoid trying to map the same physical address to the
IOMMU in physical mode while still making sure that we don't
accidentally unmap that physical address before we are done referencing
it.

Change-Id: I947408411538b921bdc5a89ce8d5e40fd826e971
Signed-off-by: default avatarSeth Howell <seth.howell@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/483133


Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: SPDK CI Jenkins <sys_sgci@intel.com>
parent f0ca01e1

lib/env_dpdk/memory.c

+34 −0
Original line number Diff line number Diff line
@@ -778,14 +778,23 @@ static TAILQ_HEAD(, spdk_vtophys_pci_device) g_vtophys_pci_devices = 
	TAILQ_HEAD_INITIALIZER(g_vtophys_pci_devices);



static struct spdk_mem_map *g_vtophys_map;

static struct spdk_mem_map *g_phys_ref_map;



#if SPDK_VFIO_ENABLED

static int

vtophys_iommu_map_dma(uint64_t vaddr, uint64_t iova, uint64_t size)

{

	struct spdk_vfio_dma_map *dma_map;

	uint64_t refcount;

	int ret;



	refcount = spdk_mem_map_translate(g_phys_ref_map, iova, NULL);

	assert(refcount < UINT64_MAX);

	if (refcount > 0) {

		spdk_mem_map_set_translation(g_phys_ref_map, iova, size, refcount + 1);

		return 0;

	}



	dma_map = calloc(1, sizeof(*dma_map));

	if (dma_map == NULL) {

		return -ENOMEM;
@@ -832,6 +841,7 @@ vtophys_iommu_map_dma(uint64_t vaddr, uint64_t iova, uint64_t size) 
out_insert:

	TAILQ_INSERT_TAIL(&g_vfio.maps, dma_map, tailq);

	pthread_mutex_unlock(&g_vfio.mutex);

	spdk_mem_map_set_translation(g_phys_ref_map, iova, size, refcount + 1);

	return 0;

}
@@ -839,6 +849,7 @@ static int 
vtophys_iommu_unmap_dma(uint64_t iova, uint64_t size)

{

	struct spdk_vfio_dma_map *dma_map;

	uint64_t refcount;

	int ret;



	pthread_mutex_lock(&g_vfio.mutex);
@@ -854,6 +865,18 @@ vtophys_iommu_unmap_dma(uint64_t iova, uint64_t size) 
		return -ENXIO;

	}



	refcount = spdk_mem_map_translate(g_phys_ref_map, iova, NULL);

	assert(refcount < UINT64_MAX);

	if (refcount > 0) {

		spdk_mem_map_set_translation(g_phys_ref_map, iova, size, refcount - 1);

	}



	/* We still have outstanding references, don't clear it. */

	if (refcount > 1) {

		pthread_mutex_unlock(&g_vfio.mutex);

		return 0;

	}



	/** don't support partial or multiple-page unmap for now */

	assert(dma_map->map.size == size);
@@ -1383,10 +1406,21 @@ spdk_vtophys_init(void) 
		.are_contiguous = vtophys_check_contiguous_entries,

	};



	const struct spdk_mem_map_ops phys_ref_map_ops = {

		.notify_cb = NULL,

		.are_contiguous = NULL,

	};



#if SPDK_VFIO_ENABLED

	spdk_vtophys_iommu_init();

#endif



	g_phys_ref_map = spdk_mem_map_alloc(0, &phys_ref_map_ops, NULL);

	if (g_phys_ref_map == NULL) {

		DEBUG_PRINT("phys_ref map allocation failed.\n");

		return -ENOMEM;

	}



	g_vtophys_map = spdk_mem_map_alloc(SPDK_VTOPHYS_ERROR, &vtophys_map_ops, NULL);

	if (g_vtophys_map == NULL) {

		DEBUG_PRINT("vtophys map allocation failed\n");