vfio: map contiguous areas in one go

[dpdk.git] / lib / librte_eal / linux / eal / eal_vfio.c

diff --git a/lib/librte_eal/linux/eal/eal_vfio.c b/lib/librte_eal/linux/eal/eal_vfio.c
index 01b5ef3..4502aef 100644 (file)
--- a/lib/librte_eal/linux/eal/eal_vfio.c
+++ b/lib/librte_eal/linux/eal/eal_vfio.c
@@ -514,9 +514,11 @@ static void
 vfio_mem_event_callback(enum rte_mem_event type, const void *addr, size_t len,
                void *arg __rte_unused)
 {
+       rte_iova_t iova_start, iova_expected;
        struct rte_memseg_list *msl;
        struct rte_memseg *ms;
        size_t cur_len = 0;
+       uint64_t va_start;
 
        msl = rte_mem_virt2memseg_list(addr);
 
@@ -545,22 +547,63 @@ vfio_mem_event_callback(enum rte_mem_event type, const void *addr, size_t len,
 #endif
        /* memsegs are contiguous in memory */
        ms = rte_mem_virt2memseg(addr, msl);
+
+       /*
+        * This memory is not guaranteed to be contiguous, but it still could
+        * be, or it could have some small contiguous chunks. Since the number
+        * of VFIO mappings is limited, and VFIO appears to not concatenate
+        * adjacent mappings, we have to do this ourselves.
+        *
+        * So, find contiguous chunks, then map them.
+        */
+       va_start = ms->addr_64;
+       iova_start = iova_expected = ms->iova;
        while (cur_len < len) {
+               bool new_contig_area = ms->iova != iova_expected;
+               bool last_seg = (len - cur_len) == ms->len;
+               bool skip_last = false;
+
+               /* only do mappings when current contiguous area ends */
+               if (new_contig_area) {
+                       if (type == RTE_MEM_EVENT_ALLOC)
+                               vfio_dma_mem_map(default_vfio_cfg, va_start,
+                                               iova_start,
+                                               iova_expected - iova_start, 1);
+                       else
+                               vfio_dma_mem_map(default_vfio_cfg, va_start,
+                                               iova_start,
+                                               iova_expected - iova_start, 0);
+                       va_start = ms->addr_64;
+                       iova_start = ms->iova;
+               }
                /* some memory segments may have invalid IOVA */
                if (ms->iova == RTE_BAD_IOVA) {
                        RTE_LOG(DEBUG, EAL, "Memory segment at %p has bad IOVA, skipping\n",
                                        ms->addr);
-                       goto next;
+                       skip_last = true;
                }
-               if (type == RTE_MEM_EVENT_ALLOC)
-                       vfio_dma_mem_map(default_vfio_cfg, ms->addr_64,
-                                       ms->iova, ms->len, 1);
-               else
-                       vfio_dma_mem_map(default_vfio_cfg, ms->addr_64,
-                                       ms->iova, ms->len, 0);
-next:
+               iova_expected = ms->iova + ms->len;
                cur_len += ms->len;
                ++ms;
+
+               /*
+                * don't count previous segment, and don't attempt to
+                * dereference a potentially invalid pointer.
+                */
+               if (skip_last && !last_seg) {
+                       iova_expected = iova_start = ms->iova;
+                       va_start = ms->addr_64;
+               } else if (!skip_last && last_seg) {
+                       /* this is the last segment and we're not skipping */
+                       if (type == RTE_MEM_EVENT_ALLOC)
+                               vfio_dma_mem_map(default_vfio_cfg, va_start,
+                                               iova_start,
+                                               iova_expected - iova_start, 1);
+                       else
+                               vfio_dma_mem_map(default_vfio_cfg, va_start,
+                                               iova_start,
+                                               iova_expected - iova_start, 0);
+               }
        }
 #ifdef RTE_ARCH_PPC_64
        cur_len = 0;