[PATCH v2 15/22] intel_iommu: bind/unbind guest page table to host

[Liu Yi L <yi.l.liu@intel.com>]

This patch captures the guest PASID table entry modifications and
propagates the changes to host to setup dual stage DMA translation.
The guest page table is configured as 1st level page table (GVA->GPA)
whose translation result would further go through host VT-d 2nd
level page table(GPA->HPA) under nested translation mode. This is the
key part of vSVA support, and also a key to support IOVA over 1st-
level page table for Intel VT-d in virtualization environment.

Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Yi Sun <yi.y.sun@linux.intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
---
 hw/i386/intel_iommu.c          | 98 +++++++++++++++++++++++++++++++++++++++---
 hw/i386/intel_iommu_internal.h | 18 ++++++++
 2 files changed, 111 insertions(+), 5 deletions(-)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index a7e9973..d87f608 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -41,6 +41,7 @@
 #include "migration/vmstate.h"
 #include "trace.h"
 #include "qemu/jhash.h"
+#include <linux/iommu.h>
 
 /* context entry operations */
 #define VTD_CE_GET_RID2PASID(ce) \
@@ -700,6 +701,16 @@ static inline uint32_t vtd_sm_ce_get_pdt_entry_num(VTDContextEntry *ce)
     return 1U << (VTD_SM_CONTEXT_ENTRY_PDTS(ce->val[0]) + 7);
 }
 
+static inline uint32_t vtd_pe_get_fl_aw(VTDPASIDEntry *pe)
+{
+    return 48 + ((pe->val[2] >> 2) & VTD_SM_PASID_ENTRY_FLPM) * 9;
+}
+
+static inline dma_addr_t vtd_pe_get_flpt_base(VTDPASIDEntry *pe)
+{
+    return pe->val[2] & VTD_SM_PASID_ENTRY_FLPTPTR;
+}
+
 static inline bool vtd_pdire_present(VTDPASIDDirEntry *pdire)
 {
     return pdire->val & 1;
@@ -1861,6 +1872,82 @@ static void vtd_context_global_invalidate(IntelIOMMUState *s)
     vtd_iommu_replay_all(s);
 }
 
+/**
+ * Caller should hold iommu_lock.
+ */
+static int vtd_bind_guest_pasid(IntelIOMMUState *s, VTDBus *vtd_bus,
+                                int devfn, int pasid, VTDPASIDEntry *pe,
+                                VTDPASIDOp op)
+{
+    VTDHostIOMMUContext *vtd_dev_icx;
+    HostIOMMUContext *iommu_ctx;
+    DualIOMMUStage1BindData *bind_data;
+    struct iommu_gpasid_bind_data *g_bind_data;
+    int ret = -1;
+
+    vtd_dev_icx = vtd_bus->dev_icx[devfn];
+    if (!vtd_dev_icx) {
+        /* means no need to go further, e.g. for emulated devices */
+        return 0;
+    }
+
+    iommu_ctx = vtd_dev_icx->iommu_ctx;
+    if (!iommu_ctx) {
+        return -EINVAL;
+    }
+
+    if (!(iommu_ctx->stage1_formats
+             & IOMMU_PASID_FORMAT_INTEL_VTD)) {
+        error_report_once("IOMMU Stage 1 format is not compatible!\n");
+        return -EINVAL;
+    }
+
+    bind_data = g_malloc0(sizeof(*bind_data));
+    bind_data->pasid = pasid;
+    g_bind_data = &bind_data->bind_data.gpasid_bind;
+
+    g_bind_data->flags = 0;
+    g_bind_data->vtd.flags = 0;
+    switch (op) {
+    case VTD_PASID_BIND:
+        g_bind_data->version = IOMMU_UAPI_VERSION;
+        g_bind_data->format = IOMMU_PASID_FORMAT_INTEL_VTD;
+        g_bind_data->gpgd = vtd_pe_get_flpt_base(pe);
+        g_bind_data->addr_width = vtd_pe_get_fl_aw(pe);
+        g_bind_data->hpasid = pasid;
+        g_bind_data->gpasid = pasid;
+        g_bind_data->flags |= IOMMU_SVA_GPASID_VAL;
+        g_bind_data->vtd.flags =
+                             (VTD_SM_PASID_ENTRY_SRE_BIT(pe->val[2]) ? 1 : 0)
+                           | (VTD_SM_PASID_ENTRY_EAFE_BIT(pe->val[2]) ? 1 : 0)
+                           | (VTD_SM_PASID_ENTRY_PCD_BIT(pe->val[1]) ? 1 : 0)
+                           | (VTD_SM_PASID_ENTRY_PWT_BIT(pe->val[1]) ? 1 : 0)
+                           | (VTD_SM_PASID_ENTRY_EMTE_BIT(pe->val[1]) ? 1 : 0)
+                           | (VTD_SM_PASID_ENTRY_CD_BIT(pe->val[1]) ? 1 : 0);
+        g_bind_data->vtd.pat = VTD_SM_PASID_ENTRY_PAT(pe->val[1]);
+        g_bind_data->vtd.emt = VTD_SM_PASID_ENTRY_EMT(pe->val[1]);
+        ret = host_iommu_ctx_bind_stage1_pgtbl(iommu_ctx, bind_data);
+        break;
+    case VTD_PASID_UNBIND:
+        g_bind_data->version = IOMMU_UAPI_VERSION;
+        g_bind_data->format = IOMMU_PASID_FORMAT_INTEL_VTD;
+        g_bind_data->gpgd = 0;
+        g_bind_data->addr_width = 0;
+        g_bind_data->hpasid = pasid;
+        g_bind_data->gpasid = pasid;
+        g_bind_data->flags |= IOMMU_SVA_GPASID_VAL;
+        ret = host_iommu_ctx_unbind_stage1_pgtbl(iommu_ctx, bind_data);
+        break;
+    default:
+        error_report_once("Unknown VTDPASIDOp!!!\n");
+        break;
+    }
+
+    g_free(bind_data);
+
+    return ret;
+}
+
 /* Do a context-cache device-selective invalidation.
  * @func_mask: FM field after shifting
  */
@@ -2489,10 +2576,10 @@ static void vtd_fill_pe_in_cache(IntelIOMMUState *s,
     }
 
     pc_entry->pasid_entry = *pe;
-    /*
-     * TODO:
-     * - send pasid bind to host for passthru devices
-     */
+    vtd_bind_guest_pasid(s, vtd_pasid_as->vtd_bus,
+                         vtd_pasid_as->devfn,
+                         vtd_pasid_as->pasid,
+                         pe, VTD_PASID_BIND);
 }
 
 /**
@@ -2565,10 +2652,11 @@ static gboolean vtd_flush_pasid(gpointer key, gpointer value,
 remove:
     /*
      * TODO:
-     * - send pasid bind to host for passthru devices
      * - when pasid-base-iotlb(piotlb) infrastructure is ready,
      *   should invalidate QEMU piotlb togehter with this change.
      */
+    vtd_bind_guest_pasid(s, vtd_bus, devfn,
+                         pasid, NULL, VTD_PASID_UNBIND);
     return true;
 }
 
diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index 451ef4c..b9e48ab 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -517,6 +517,13 @@ typedef struct VTDRootEntry VTDRootEntry;
 #define VTD_SM_CONTEXT_ENTRY_RSVD_VAL0(aw)  (0x1e0ULL | ~VTD_HAW_MASK(aw))
 #define VTD_SM_CONTEXT_ENTRY_RSVD_VAL1      0xffffffffffe00000ULL
 
+enum VTDPASIDOp {
+    VTD_PASID_BIND,
+    VTD_PASID_UNBIND,
+    VTD_OP_NUM
+};
+typedef enum VTDPASIDOp VTDPASIDOp;
+
 struct VTDPASIDCacheInfo {
 #define VTD_PASID_CACHE_FORCE_RESET    (1ULL << 0)
 #define VTD_PASID_CACHE_GLOBAL         (1ULL << 1)
@@ -556,6 +563,17 @@ typedef struct VTDPASIDCacheInfo VTDPASIDCacheInfo;
 #define VTD_SM_PASID_ENTRY_AW          7ULL /* Adjusted guest-address-width */
 #define VTD_SM_PASID_ENTRY_DID(val)    ((val) & VTD_DOMAIN_ID_MASK)
 
+#define VTD_SM_PASID_ENTRY_FLPM          3ULL
+#define VTD_SM_PASID_ENTRY_FLPTPTR       (~0xfffULL)
+#define VTD_SM_PASID_ENTRY_SRE_BIT(val)  (!!((val) & 1ULL))
+#define VTD_SM_PASID_ENTRY_EAFE_BIT(val) (!!(((val) >> 7) & 1ULL))
+#define VTD_SM_PASID_ENTRY_PCD_BIT(val)  (!!(((val) >> 31) & 1ULL))
+#define VTD_SM_PASID_ENTRY_PWT_BIT(val)  (!!(((val) >> 30) & 1ULL))
+#define VTD_SM_PASID_ENTRY_EMTE_BIT(val) (!!(((val) >> 26) & 1ULL))
+#define VTD_SM_PASID_ENTRY_CD_BIT(val)   (!!(((val) >> 25) & 1ULL))
+#define VTD_SM_PASID_ENTRY_PAT(val)      (((val) >> 32) & 0xFFFFFFFFULL)
+#define VTD_SM_PASID_ENTRY_EMT(val)      (((val) >> 27) & 0x7ULL)
+
 /* Second Level Page Translation Pointer*/
 #define VTD_SM_PASID_ENTRY_SLPTPTR     (~0xfffULL)
 
-- 
2.7.4