>From 796abe4e7114d18e74cc869922cc5eb0813396c8 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <address@hidden>
Date: Tue, 7 May 2013 11:30:23 +0200
Subject: [PATCH] subpage fix

Note: this temporarily breaks RAM regions in the I/O address space, but
there is none.  It will be fixed later when the special address space
listener is dropped.

Signed-off-by: Paolo Bonzini <address@hidden>
---
 exec.c |   56 ++++++++++++--------------------------------------------
 1 files changed, 12 insertions(+), 44 deletions(-)

diff --git a/exec.c b/exec.c
index 7098632..21bd08d 100644
--- a/exec.c
+++ b/exec.c
@@ -65,7 +65,6 @@ AddressSpace address_space_io;
 AddressSpace address_space_memory;
 
 MemoryRegion io_mem_ram, io_mem_rom, io_mem_unassigned, io_mem_notdirty;
-static MemoryRegion io_mem_subpage_ram;
 
 #endif
 
@@ -80,7 +79,8 @@ int use_icount;
 
 #if !defined(CONFIG_USER_ONLY)
 
-#define SUBSECTION_IDX(addr) ((addr) & ~TARGET_PAGE_MASK)
+#define SUBSECTION_IDX(addr)      ((addr) & ~TARGET_PAGE_MASK)
+#define PHYS_SECTION_ID(psection) ((psection) - phys_sections)
 
 typedef struct PhysSection {
     MemoryRegionSection section;
@@ -695,7 +695,7 @@ hwaddr memory_region_section_get_iotlb(CPUArchState *env,
             iotlb |= phys_section_rom;
         }
     } else {
-        iotlb = container_of(section, PhysSection, section) - phys_sections;
+        iotlb = PHYS_SECTION_ID(container_of(section, PhysSection, section));
         iotlb += xlat;
     }
 
@@ -782,7 +782,7 @@ static void register_subsection(AddressSpaceDispatch *d,
         .offset_within_address_space = base,
         .size = TARGET_PAGE_SIZE,
     };
-    uint16_t new_section;
+    uint16_t new_section, new_subsection;
     hwaddr start, end;
 
     assert(psection->sub_section ||
@@ -793,10 +793,17 @@ static void register_subsection(AddressSpaceDispatch *d,
         psection = &phys_sections[new_section];
         subsections_init(psection);
         phys_page_set(d, base >> TARGET_PAGE_BITS, 1, new_section);
+    } else {
+        new_section = PHYS_SECTION_ID(psection);
     }
+
+    new_subsection = phys_section_add(section);
+
+    /* phys_section_add invalidates psection, reload it  */
+    psection = &phys_sections[new_section];
     start = section->offset_within_address_space & ~TARGET_PAGE_MASK;
     end = start + section->size - 1;
-    subsection_register(psection, start, end, phys_section_add(section));
+    subsection_register(psection, start, end, new_subsection);
 }
 
 
@@ -1607,38 +1614,6 @@ static const MemoryRegionOps watch_mem_ops = {
     .endianness = DEVICE_NATIVE_ENDIAN,
 };
 
-static uint64_t subpage_ram_read(void *opaque, hwaddr addr,
-                                 unsigned size)
-{
-    ram_addr_t raddr = addr;
-    void *ptr = qemu_get_ram_ptr(raddr);
-    switch (size) {
-    case 1: return ldub_p(ptr);
-    case 2: return lduw_p(ptr);
-    case 4: return ldl_p(ptr);
-    default: abort();
-    }
-}
-
-static void subpage_ram_write(void *opaque, hwaddr addr,
-                              uint64_t value, unsigned size)
-{
-    ram_addr_t raddr = addr;
-    void *ptr = qemu_get_ram_ptr(raddr);
-    switch (size) {
-    case 1: return stb_p(ptr, value);
-    case 2: return stw_p(ptr, value);
-    case 4: return stl_p(ptr, value);
-    default: abort();
-    }
-}
-
-static const MemoryRegionOps subpage_ram_ops = {
-    .read = subpage_ram_read,
-    .write = subpage_ram_write,
-    .endianness = DEVICE_NATIVE_ENDIAN,
-};
-
 static int subsection_register(PhysSection *psection, uint32_t start,
                                uint32_t end, uint16_t section)
 {
@@ -1648,11 +1623,6 @@ static int subsection_register(PhysSection *psection, uint32_t start,
         return -1;
     idx = SUBSECTION_IDX(start);
     eidx = SUBSECTION_IDX(end);
-    if (memory_region_is_ram(phys_sections[section].section.mr)) {
-        MemoryRegionSection new_section = phys_sections[section].section;
-        new_section.mr = &io_mem_subpage_ram;
-        section = phys_section_add(&new_section);
-    }
     for (; idx <= eidx; idx++) {
         psection->sub_section[idx] = section;
     }
@@ -1692,8 +1662,6 @@ static void io_mem_init(void)
                           "unassigned", UINT64_MAX);
     memory_region_init_io(&io_mem_notdirty, &notdirty_mem_ops, NULL,
                           "notdirty", UINT64_MAX);
-    memory_region_init_io(&io_mem_subpage_ram, &subpage_ram_ops, NULL,
-                          "subpage-ram", UINT64_MAX);
     memory_region_init_io(&io_mem_watch, &watch_mem_ops, NULL,
                           "watch", UINT64_MAX);
 }
-- 
1.7.1