1 files changed, 73 insertions, 19 deletions

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 609b80750a..a523ef0e65 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -686,9 +686,18 @@ static inline bool vtd_pe_type_check(X86IOMMUState *x86_iommu,
     return true;
 }
 
-static int vtd_get_pasid_dire(dma_addr_t pasid_dir_base,
-                              uint32_t pasid,
-                              VTDPASIDDirEntry *pdire)
+static inline bool vtd_pdire_present(VTDPASIDDirEntry *pdire)
+{
+    return pdire->val & 1;
+}
+
+/**
+ * Caller of this function should check present bit if wants
+ * to use pdir entry for futher usage except for fpd bit check.
+ */
+static int vtd_get_pdire_from_pdir_table(dma_addr_t pasid_dir_base,
+                                         uint32_t pasid,
+                                         VTDPASIDDirEntry *pdire)
 {
     uint32_t index;
     dma_addr_t addr, entry_size;
@@ -703,18 +712,22 @@ static int vtd_get_pasid_dire(dma_addr_t pasid_dir_base,
     return 0;
 }
 
-static int vtd_get_pasid_entry(IntelIOMMUState *s,
-                               uint32_t pasid,
-                               VTDPASIDDirEntry *pdire,
-                               VTDPASIDEntry *pe)
+static inline bool vtd_pe_present(VTDPASIDEntry *pe)
+{
+    return pe->val[0] & VTD_PASID_ENTRY_P;
+}
+
+static int vtd_get_pe_in_pasid_leaf_table(IntelIOMMUState *s,
+                                          uint32_t pasid,
+                                          dma_addr_t addr,
+                                          VTDPASIDEntry *pe)
 {
     uint32_t index;
-    dma_addr_t addr, entry_size;
+    dma_addr_t entry_size;
     X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(s);
 
     index = VTD_PASID_TABLE_INDEX(pasid);
     entry_size = VTD_PASID_ENTRY_SIZE;
-    addr = pdire->val & VTD_PASID_TABLE_BASE_ADDR_MASK;
     addr = addr + index * entry_size;
     if (dma_memory_read(&address_space_memory, addr, pe, entry_size)) {
         return -VTD_FR_PASID_TABLE_INV;
@@ -732,25 +745,54 @@ static int vtd_get_pasid_entry(IntelIOMMUState *s,
     return 0;
 }
 
-static int vtd_get_pasid_entry_from_pasid(IntelIOMMUState *s,
-                                          dma_addr_t pasid_dir_base,
-                                          uint32_t pasid,
-                                          VTDPASIDEntry *pe)
+/**
+ * Caller of this function should check present bit if wants
+ * to use pasid entry for futher usage except for fpd bit check.
+ */
+static int vtd_get_pe_from_pdire(IntelIOMMUState *s,
+                                 uint32_t pasid,
+                                 VTDPASIDDirEntry *pdire,
+                                 VTDPASIDEntry *pe)
+{
+    dma_addr_t addr = pdire->val & VTD_PASID_TABLE_BASE_ADDR_MASK;
+
+    return vtd_get_pe_in_pasid_leaf_table(s, pasid, addr, pe);
+}
+
+/**
+ * This function gets a pasid entry from a specified pasid
+ * table (includes dir and leaf table) with a specified pasid.
+ * Sanity check should be done to ensure return a present
+ * pasid entry to caller.
+ */
+static int vtd_get_pe_from_pasid_table(IntelIOMMUState *s,
+                                       dma_addr_t pasid_dir_base,
+                                       uint32_t pasid,
+                                       VTDPASIDEntry *pe)
 {
     int ret;
     VTDPASIDDirEntry pdire;
 
-    ret = vtd_get_pasid_dire(pasid_dir_base, pasid, &pdire);
+    ret = vtd_get_pdire_from_pdir_table(pasid_dir_base,
+                                        pasid, &pdire);
     if (ret) {
         return ret;
     }
 
-    ret = vtd_get_pasid_entry(s, pasid, &pdire, pe);
+    if (!vtd_pdire_present(&pdire)) {
+        return -VTD_FR_PASID_TABLE_INV;
+    }
+
+    ret = vtd_get_pe_from_pdire(s, pasid, &pdire, pe);
     if (ret) {
         return ret;
     }
 
-    return ret;
+    if (!vtd_pe_present(pe)) {
+        return -VTD_FR_PASID_TABLE_INV;
+    }
+
+    return 0;
 }
 
 static int vtd_ce_get_rid2pasid_entry(IntelIOMMUState *s,
@@ -763,7 +805,7 @@ static int vtd_ce_get_rid2pasid_entry(IntelIOMMUState *s,
 
     pasid = VTD_CE_GET_RID2PASID(ce);
     pasid_dir_base = VTD_CE_GET_PASID_DIR_TABLE(ce);
-    ret = vtd_get_pasid_entry_from_pasid(s, pasid_dir_base, pasid, pe);
+    ret = vtd_get_pe_from_pasid_table(s, pasid_dir_base, pasid, pe);
 
     return ret;
 }
@@ -781,7 +823,11 @@ static int vtd_ce_get_pasid_fpd(IntelIOMMUState *s,
     pasid = VTD_CE_GET_RID2PASID(ce);
     pasid_dir_base = VTD_CE_GET_PASID_DIR_TABLE(ce);
 
-    ret = vtd_get_pasid_dire(pasid_dir_base, pasid, &pdire);
+    /*
+     * No present bit check since fpd is meaningful even
+     * if the present bit is clear.
+     */
+    ret = vtd_get_pdire_from_pdir_table(pasid_dir_base, pasid, &pdire);
     if (ret) {
         return ret;
     }
@@ -791,7 +837,15 @@ static int vtd_ce_get_pasid_fpd(IntelIOMMUState *s,
         return 0;
     }
 
-    ret = vtd_get_pasid_entry(s, pasid, &pdire, &pe);
+    if (!vtd_pdire_present(&pdire)) {
+        return -VTD_FR_PASID_TABLE_INV;
+    }
+
+    /*
+     * No present bit check since fpd is meaningful even
+     * if the present bit is clear.
+     */
+    ret = vtd_get_pe_from_pdire(s, pasid, &pdire, &pe);
     if (ret) {
         return ret;
     }