bus/fslmc: support memory event callbacks for VFIO

VFIO needs to map and unmap segments for DMA whenever they
become available or unavailable, so register a callback for
memory events, and provide map/unmap functions.

Remove unneeded check for number of segments, as in non-legacy
mode this now becomes a valid scenario.

Signed-off-by: Shreyansh Jain <shreyansh.jain@nxp.com>
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Tested-by: Santosh Shukla <santosh.shukla@caviumnetworks.com>
Tested-by: Hemant Agrawal <hemant.agrawal@nxp.com>
Tested-by: Gowrishankar Muthukrishnan <gowrishankar.m@linux.vnet.ibm.com>

diff --git a/drivers/bus/fslmc/fslmc_vfio.c b/drivers/bus/fslmc/fslmc_vfio.c
index db3eb61..625fa7c 100644 (file)
--- a/drivers/bus/fslmc/fslmc_vfio.c
+++ b/drivers/bus/fslmc/fslmc_vfio.c
@@ -30,6 +30,7 @@
 #include <rte_kvargs.h>
 #include <rte_dev.h>
 #include <rte_bus.h>
+#include <rte_eal_memconfig.h>
 
 #include "rte_fslmc.h"
 #include "fslmc_vfio.h"
@@ -188,11 +189,62 @@ static int vfio_map_irq_region(struct fslmc_vfio_group *group)
        return -errno;
 }
 
+static int fslmc_map_dma(uint64_t vaddr, rte_iova_t iovaddr, size_t len);
+static int fslmc_unmap_dma(uint64_t vaddr, rte_iova_t iovaddr, size_t len);
+
+static void
+fslmc_memevent_cb(enum rte_mem_event type, const void *addr, size_t len)
+{
+       struct rte_memseg_list *msl;
+       struct rte_memseg *ms;
+       size_t cur_len = 0, map_len = 0;
+       uint64_t virt_addr;
+       rte_iova_t iova_addr;
+       int ret;
+
+       msl = rte_mem_virt2memseg_list(addr);
+
+       while (cur_len < len) {
+               const void *va = RTE_PTR_ADD(addr, cur_len);
+
+               ms = rte_mem_virt2memseg(va, msl);
+               iova_addr = ms->iova;
+               virt_addr = ms->addr_64;
+               map_len = ms->len;
+
+               DPAA2_BUS_DEBUG("Request for %s, va=%p, "
+                               "virt_addr=0x%" PRIx64 ", "
+                               "iova=0x%" PRIx64 ", map_len=%zu",
+                               type == RTE_MEM_EVENT_ALLOC ?
+                                       "alloc" : "dealloc",
+                               va, virt_addr, iova_addr, map_len);
+
+               if (type == RTE_MEM_EVENT_ALLOC)
+                       ret = fslmc_map_dma(virt_addr, iova_addr, map_len);
+               else
+                       ret = fslmc_unmap_dma(virt_addr, iova_addr, map_len);
+
+               if (ret != 0) {
+                       DPAA2_BUS_ERR("DMA Mapping/Unmapping failed. "
+                                       "Map=%d, addr=%p, len=%zu, err:(%d)",
+                                       type, va, map_len, ret);
+                       return;
+               }
+
+               cur_len += map_len;
+       }
+
+       if (type == RTE_MEM_EVENT_ALLOC)
+               DPAA2_BUS_DEBUG("Total Mapped: addr=%p, len=%zu",
+                               addr, len);
+       else
+               DPAA2_BUS_DEBUG("Total Unmapped: addr=%p, len=%zu",
+                               addr, len);
+}
+
 static int
-fslmc_vfio_map(const struct rte_memseg_list *msl __rte_unused,
-               const struct rte_memseg *ms, void *arg)
+fslmc_map_dma(uint64_t vaddr, rte_iova_t iovaddr __rte_unused, size_t len)
 {
-       int *n_segs = arg;
        struct fslmc_vfio_group *group;
        struct vfio_iommu_type1_dma_map dma_map = {
                .argsz = sizeof(struct vfio_iommu_type1_dma_map),
@@ -200,10 +252,11 @@ fslmc_vfio_map(const struct rte_memseg_list *msl __rte_unused,
        };
        int ret;
 
-       dma_map.size = ms->len;
-       dma_map.vaddr = ms->addr_64;
+       dma_map.size = len;
+       dma_map.vaddr = vaddr;
+
 #ifdef RTE_LIBRTE_DPAA2_USE_PHYS_IOVA
-       dma_map.iova = ms->iova;
+       dma_map.iova = iovaddr;
 #else
        dma_map.iova = dma_map.vaddr;
 #endif
@@ -216,32 +269,91 @@ fslmc_vfio_map(const struct rte_memseg_list *msl __rte_unused,
                return -1;
        }
 
-       DPAA2_BUS_DEBUG("-->Initial SHM Virtual ADDR %llX",
-                       dma_map.vaddr);
-       DPAA2_BUS_DEBUG("-----> DMA size 0x%llX", dma_map.size);
-       ret = ioctl(group->container->fd, VFIO_IOMMU_MAP_DMA,
-                       &dma_map);
+       DPAA2_BUS_DEBUG("--> Map address: %llX, size: 0x%llX",
+                       dma_map.vaddr, dma_map.size);
+       ret = ioctl(group->container->fd, VFIO_IOMMU_MAP_DMA, &dma_map);
        if (ret) {
                DPAA2_BUS_ERR("VFIO_IOMMU_MAP_DMA API(errno = %d)",
                                errno);
                return -1;
        }
-       (*n_segs)++;
+
        return 0;
 }
 
-int rte_fslmc_vfio_dmamap(void)
+static int
+fslmc_unmap_dma(uint64_t vaddr, uint64_t iovaddr __rte_unused, size_t len)
 {
-       int i = 0;
+       struct fslmc_vfio_group *group;
+       struct vfio_iommu_type1_dma_unmap dma_unmap = {
+               .argsz = sizeof(struct vfio_iommu_type1_dma_unmap),
+               .flags = 0,
+       };
+       int ret;
+
+       dma_unmap.size = len;
+       dma_unmap.iova = vaddr;
 
-       if (rte_memseg_walk(fslmc_vfio_map, &i) < 0)
+       /* SET DMA MAP for IOMMU */
+       group = &vfio_group;
+
+       if (!group->container) {
+               DPAA2_BUS_ERR("Container is not connected ");
                return -1;
+       }
 
-       /* Verifying that at least single segment is available */
-       if (i <= 0) {
-               DPAA2_BUS_ERR("No Segments found for VFIO Mapping");
+       DPAA2_BUS_DEBUG("--> Unmap address: %llX, size: 0x%llX",
+                       dma_unmap.iova, dma_unmap.size);
+       ret = ioctl(group->container->fd, VFIO_IOMMU_UNMAP_DMA, &dma_unmap);
+       if (ret) {
+               DPAA2_BUS_ERR("VFIO_IOMMU_UNMAP_DMA API(errno = %d)",
+                               errno);
                return -1;
        }
+
+       return 0;
+}
+
+static int
+fslmc_dmamap_seg(const struct rte_memseg_list *msl __rte_unused,
+                const struct rte_memseg *ms, void *arg)
+{
+       int *n_segs = arg;
+       int ret;
+
+       ret = fslmc_map_dma(ms->addr_64, ms->iova, ms->len);
+       if (ret)
+               DPAA2_BUS_ERR("Unable to VFIO map (addr=%p, len=%zu)",
+                               ms->addr, ms->len);
+       else
+               (*n_segs)++;
+
+       return ret;
+}
+
+int rte_fslmc_vfio_dmamap(void)
+{
+       int i = 0, ret;
+       struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
+       rte_rwlock_t *mem_lock = &mcfg->memory_hotplug_lock;
+
+       /* Lock before parsing and registering callback to memory subsystem */
+       rte_rwlock_read_lock(mem_lock);
+
+       if (rte_memseg_walk(fslmc_dmamap_seg, &i) < 0) {
+               rte_rwlock_read_unlock(mem_lock);
+               return -1;
+       }
+
+       ret = rte_mem_event_callback_register("fslmc_memevent_clb",
+                                             fslmc_memevent_cb);
+       if (ret && rte_errno == ENOTSUP)
+               DPAA2_BUS_DEBUG("Memory event callbacks not supported");
+       else if (ret)
+               DPAA2_BUS_DEBUG("Unable to install memory handler");
+       else
+               DPAA2_BUS_DEBUG("Installed memory callback handler");
+
        DPAA2_BUS_DEBUG("Total %d segments found.", i);
 
        /* TODO - This is a W.A. as VFIO currently does not add the mapping of
@@ -250,6 +362,11 @@ int rte_fslmc_vfio_dmamap(void)
         */
        vfio_map_irq_region(&vfio_group);
 
+       /* Existing segments have been mapped and memory callback for hotplug
+        * has been installed.
+        */
+       rte_rwlock_read_unlock(mem_lock);
+
        return 0;
 }