[PATCH v2 4/6] Convert x86_cpu_get_memory_mapping() to use generic iterators

Don Porter posted 6 patches 6 months ago
Maintainers: "Dr. David Alan Gilbert" <dave@treblig.org>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <richard.henderson@linaro.org>, Eduardo Habkost <eduardo@habkost.net>
There is a newer version of this series
[PATCH v2 4/6] Convert x86_cpu_get_memory_mapping() to use generic iterators
Posted by Don Porter 6 months ago
Signed-off-by: Don Porter <porter@cs.unc.edu>
---
 target/i386/arch_memory_mapping.c | 318 ++++--------------------------
 1 file changed, 40 insertions(+), 278 deletions(-)

diff --git a/target/i386/arch_memory_mapping.c b/target/i386/arch_memory_mapping.c
index 00bf2a2116..040464dd34 100644
--- a/target/i386/arch_memory_mapping.c
+++ b/target/i386/arch_memory_mapping.c
@@ -19,6 +19,7 @@
  ************** code hook implementations for x86 ***********
  */
 
+/* PAE Paging or IA-32e Paging */
 #define PML4_ADDR_MASK 0xffffffffff000ULL /* selects bits 51:12 */
 
 /**
@@ -499,302 +500,63 @@ bool for_each_pte(CPUState *cs,
 /**
  * Back to x86 hooks
  */
+struct memory_mapping_data {
+    MemoryMappingList *list;
+};
 
-/* PAE Paging or IA-32e Paging */
-static void walk_pte(MemoryMappingList *list, AddressSpace *as,
-                     hwaddr pte_start_addr,
-                     int32_t a20_mask, target_ulong start_line_addr)
-{
-    hwaddr pte_addr, start_paddr;
-    uint64_t pte;
-    target_ulong start_vaddr;
-    int i;
-
-    for (i = 0; i < 512; i++) {
-        pte_addr = (pte_start_addr + i * 8) & a20_mask;
-        pte = address_space_ldq(as, pte_addr, MEMTXATTRS_UNSPECIFIED, NULL);
-        if (!(pte & PG_PRESENT_MASK)) {
-            /* not present */
-            continue;
-        }
-
-        start_paddr = (pte & ~0xfff) & ~(0x1ULL << 63);
-        if (cpu_physical_memory_is_io(start_paddr)) {
-            /* I/O region */
-            continue;
-        }
-
-        start_vaddr = start_line_addr | ((i & 0x1ff) << 12);
-        memory_mapping_list_add_merge_sorted(list, start_paddr,
-                                             start_vaddr, 1 << 12);
-    }
-}
-
-/* 32-bit Paging */
-static void walk_pte2(MemoryMappingList *list, AddressSpace *as,
-                      hwaddr pte_start_addr, int32_t a20_mask,
-                      target_ulong start_line_addr)
-{
-    hwaddr pte_addr, start_paddr;
-    uint32_t pte;
-    target_ulong start_vaddr;
-    int i;
-
-    for (i = 0; i < 1024; i++) {
-        pte_addr = (pte_start_addr + i * 4) & a20_mask;
-        pte = address_space_ldl(as, pte_addr, MEMTXATTRS_UNSPECIFIED, NULL);
-        if (!(pte & PG_PRESENT_MASK)) {
-            /* not present */
-            continue;
-        }
-
-        start_paddr = pte & ~0xfff;
-        if (cpu_physical_memory_is_io(start_paddr)) {
-            /* I/O region */
-            continue;
-        }
-
-        start_vaddr = start_line_addr | ((i & 0x3ff) << 12);
-        memory_mapping_list_add_merge_sorted(list, start_paddr,
-                                             start_vaddr, 1 << 12);
-    }
-}
-
-/* PAE Paging or IA-32e Paging */
-#define PLM4_ADDR_MASK 0xffffffffff000ULL /* selects bits 51:12 */
-
-static void walk_pde(MemoryMappingList *list, AddressSpace *as,
-                     hwaddr pde_start_addr,
-                     int32_t a20_mask, target_ulong start_line_addr)
+static int add_memory_mapping_to_list(CPUState *cs, void *data, PTE_t *pte,
+                                      target_ulong vaddr, int height,
+                                      int offset)
 {
-    hwaddr pde_addr, pte_start_addr, start_paddr;
-    uint64_t pde;
-    target_ulong line_addr, start_vaddr;
-    int i;
-
-    for (i = 0; i < 512; i++) {
-        pde_addr = (pde_start_addr + i * 8) & a20_mask;
-        pde = address_space_ldq(as, pde_addr, MEMTXATTRS_UNSPECIFIED, NULL);
-        if (!(pde & PG_PRESENT_MASK)) {
-            /* not present */
-            continue;
-        }
-
-        line_addr = start_line_addr | ((i & 0x1ff) << 21);
-        if (pde & PG_PSE_MASK) {
-            /* 2 MB page */
-            start_paddr = (pde & ~0x1fffff) & ~(0x1ULL << 63);
-            if (cpu_physical_memory_is_io(start_paddr)) {
-                /* I/O region */
-                continue;
-            }
-            start_vaddr = line_addr;
-            memory_mapping_list_add_merge_sorted(list, start_paddr,
-                                                 start_vaddr, 1 << 21);
-            continue;
-        }
-
-        pte_start_addr = (pde & PLM4_ADDR_MASK) & a20_mask;
-        walk_pte(list, as, pte_start_addr, a20_mask, line_addr);
-    }
-}
+    X86CPU *cpu = X86_CPU(cs);
+    CPUX86State *env = &cpu->env;
 
-/* 32-bit Paging */
-static void walk_pde2(MemoryMappingList *list, AddressSpace *as,
-                      hwaddr pde_start_addr, int32_t a20_mask,
-                      bool pse)
-{
-    hwaddr pde_addr, pte_start_addr, start_paddr, high_paddr;
-    uint32_t pde;
-    target_ulong line_addr, start_vaddr;
-    int i;
+    struct memory_mapping_data *mm_data = (struct memory_mapping_data *) data;
 
-    for (i = 0; i < 1024; i++) {
-        pde_addr = (pde_start_addr + i * 4) & a20_mask;
-        pde = address_space_ldl(as, pde_addr, MEMTXATTRS_UNSPECIFIED, NULL);
-        if (!(pde & PG_PRESENT_MASK)) {
-            /* not present */
-            continue;
+    hwaddr start_paddr = 0;
+    size_t pg_size = mmu_pte_leaf_page_size(cs, height);
+    switch (height) {
+    case 1:
+        start_paddr = pte->pte64_t & ~0xfff;
+        if (env->cr[4] & CR4_PAE_MASK) {
+            start_paddr &= ~(0x1ULL << 63);
         }
-
-        line_addr = (((unsigned int)i & 0x3ff) << 22);
-        if ((pde & PG_PSE_MASK) && pse) {
+        break;
+    case 2:
+        if (env->cr[4] & CR4_PAE_MASK) {
+            start_paddr = (pte->pte64_t & ~0x1fffff) & ~(0x1ULL << 63);
+        } else {
+            assert(!!(env->cr[4] & CR4_PSE_MASK));
             /*
              * 4 MB page:
              * bits 39:32 are bits 20:13 of the PDE
              * bit3 31:22 are bits 31:22 of the PDE
              */
-            high_paddr = ((hwaddr)(pde & 0x1fe000) << 19);
-            start_paddr = (pde & ~0x3fffff) | high_paddr;
-            if (cpu_physical_memory_is_io(start_paddr)) {
-                /* I/O region */
-                continue;
-            }
-            start_vaddr = line_addr;
-            memory_mapping_list_add_merge_sorted(list, start_paddr,
-                                                 start_vaddr, 1 << 22);
-            continue;
-        }
-
-        pte_start_addr = (pde & ~0xfff) & a20_mask;
-        walk_pte2(list, as, pte_start_addr, a20_mask, line_addr);
-    }
-}
-
-/* PAE Paging */
-static void walk_pdpe2(MemoryMappingList *list, AddressSpace *as,
-                       hwaddr pdpe_start_addr, int32_t a20_mask)
-{
-    hwaddr pdpe_addr, pde_start_addr;
-    uint64_t pdpe;
-    target_ulong line_addr;
-    int i;
-
-    for (i = 0; i < 4; i++) {
-        pdpe_addr = (pdpe_start_addr + i * 8) & a20_mask;
-        pdpe = address_space_ldq(as, pdpe_addr, MEMTXATTRS_UNSPECIFIED, NULL);
-        if (!(pdpe & PG_PRESENT_MASK)) {
-            /* not present */
-            continue;
+            hwaddr high_paddr = ((hwaddr)(pte->pte64_t & 0x1fe000) << 19);
+            start_paddr = (pte->pte64_t & ~0x3fffff) | high_paddr;
         }
-
-        line_addr = (((unsigned int)i & 0x3) << 30);
-        pde_start_addr = (pdpe & ~0xfff) & a20_mask;
-        walk_pde(list, as, pde_start_addr, a20_mask, line_addr);
-    }
-}
-
-#ifdef TARGET_X86_64
-/* IA-32e Paging */
-static void walk_pdpe(MemoryMappingList *list, AddressSpace *as,
-                      hwaddr pdpe_start_addr, int32_t a20_mask,
-                      target_ulong start_line_addr)
-{
-    hwaddr pdpe_addr, pde_start_addr, start_paddr;
-    uint64_t pdpe;
-    target_ulong line_addr, start_vaddr;
-    int i;
-
-    for (i = 0; i < 512; i++) {
-        pdpe_addr = (pdpe_start_addr + i * 8) & a20_mask;
-        pdpe = address_space_ldq(as, pdpe_addr, MEMTXATTRS_UNSPECIFIED, NULL);
-        if (!(pdpe & PG_PRESENT_MASK)) {
-            /* not present */
-            continue;
-        }
-
-        line_addr = start_line_addr | ((i & 0x1ffULL) << 30);
-        if (pdpe & PG_PSE_MASK) {
-            /* 1 GB page */
-            start_paddr = (pdpe & ~0x3fffffff) & ~(0x1ULL << 63);
-            if (cpu_physical_memory_is_io(start_paddr)) {
-                /* I/O region */
-                continue;
-            }
-            start_vaddr = line_addr;
-            memory_mapping_list_add_merge_sorted(list, start_paddr,
-                                                 start_vaddr, 1 << 30);
-            continue;
-        }
-
-        pde_start_addr = (pdpe & PLM4_ADDR_MASK) & a20_mask;
-        walk_pde(list, as, pde_start_addr, a20_mask, line_addr);
+        break;
+    case 3:
+        /* Select bits 30--51 */
+        start_paddr = (pte->pte64_t & 0xfffffc0000000);
+        break;
+    default:
+        g_assert_not_reached();
     }
-}
-
-/* IA-32e Paging */
-static void walk_pml4e(MemoryMappingList *list, AddressSpace *as,
-                       hwaddr pml4e_start_addr, int32_t a20_mask,
-                       target_ulong start_line_addr)
-{
-    hwaddr pml4e_addr, pdpe_start_addr;
-    uint64_t pml4e;
-    target_ulong line_addr;
-    int i;
 
-    for (i = 0; i < 512; i++) {
-        pml4e_addr = (pml4e_start_addr + i * 8) & a20_mask;
-        pml4e = address_space_ldq(as, pml4e_addr, MEMTXATTRS_UNSPECIFIED,
-                                  NULL);
-        if (!(pml4e & PG_PRESENT_MASK)) {
-            /* not present */
-            continue;
-        }
-
-        line_addr = start_line_addr | ((i & 0x1ffULL) << 39);
-        pdpe_start_addr = (pml4e & PLM4_ADDR_MASK) & a20_mask;
-        walk_pdpe(list, as, pdpe_start_addr, a20_mask, line_addr);
+    /* This hook skips mappings for the I/O region */
+    if (cpu_physical_memory_is_io(start_paddr)) {
+        /* I/O region */
+        return 0;
     }
-}
 
-static void walk_pml5e(MemoryMappingList *list, AddressSpace *as,
-                       hwaddr pml5e_start_addr, int32_t a20_mask)
-{
-    hwaddr pml5e_addr, pml4e_start_addr;
-    uint64_t pml5e;
-    target_ulong line_addr;
-    int i;
-
-    for (i = 0; i < 512; i++) {
-        pml5e_addr = (pml5e_start_addr + i * 8) & a20_mask;
-        pml5e = address_space_ldq(as, pml5e_addr, MEMTXATTRS_UNSPECIFIED,
-                                  NULL);
-        if (!(pml5e & PG_PRESENT_MASK)) {
-            /* not present */
-            continue;
-        }
-
-        line_addr = (0x7fULL << 57) | ((i & 0x1ffULL) << 48);
-        pml4e_start_addr = (pml5e & PLM4_ADDR_MASK) & a20_mask;
-        walk_pml4e(list, as, pml4e_start_addr, a20_mask, line_addr);
-    }
+    memory_mapping_list_add_merge_sorted(mm_data->list, start_paddr,
+                                         vaddr, pg_size);
+    return 0;
 }
-#endif
 
 bool x86_cpu_get_memory_mapping(CPUState *cs, MemoryMappingList *list,
                                 Error **errp)
 {
-    X86CPU *cpu = X86_CPU(cs);
-    CPUX86State *env = &cpu->env;
-    int32_t a20_mask;
-
-    if (!cpu_paging_enabled(cs)) {
-        /* paging is disabled */
-        return true;
-    }
-
-    a20_mask = x86_get_a20_mask(env);
-    if (env->cr[4] & CR4_PAE_MASK) {
-#ifdef TARGET_X86_64
-        if (env->hflags & HF_LMA_MASK) {
-            if (env->cr[4] & CR4_LA57_MASK) {
-                hwaddr pml5e_addr;
-
-                pml5e_addr = (env->cr[3] & PLM4_ADDR_MASK) & a20_mask;
-                walk_pml5e(list, cs->as, pml5e_addr, a20_mask);
-            } else {
-                hwaddr pml4e_addr;
-
-                pml4e_addr = (env->cr[3] & PLM4_ADDR_MASK) & a20_mask;
-                walk_pml4e(list, cs->as, pml4e_addr, a20_mask,
-                        0xffffULL << 48);
-            }
-        } else
-#endif
-        {
-            hwaddr pdpe_addr;
-
-            pdpe_addr = (env->cr[3] & ~0x1f) & a20_mask;
-            walk_pdpe2(list, cs->as, pdpe_addr, a20_mask);
-        }
-    } else {
-        hwaddr pde_addr;
-        bool pse;
-
-        pde_addr = (env->cr[3] & ~0xfff) & a20_mask;
-        pse = !!(env->cr[4] & CR4_PSE_MASK);
-        walk_pde2(list, cs->as, pde_addr, a20_mask, pse);
-    }
-
-    return true;
+    return for_each_pte(cs, &add_memory_mapping_to_list, list, false, false);
 }
-- 
2.34.1