[Qemu-devel] [RFC][PATCH 09/15] memory: Introduce address_space_lookup_region

[Jan Kiszka]

This new service so far only replaces phys_page_find as public API. In a
follow-up step, it will return the effective memory region for the
specified address, i.e. after resolving what are currently sub-pages.
Moreover, it will also once encapsulate locking and reference counting
when we introduce BQL-free dispatching.

Signed-off-by: Jan Kiszka <address@hidden>
---
 cputlb.c              |    2 +-
 exec.c                |   46 +++++++++++++++++++++-------------------------
 include/exec/cputlb.h |    2 --
 include/exec/memory.h |    9 +++++++++
 translate-all.c       |    3 +--
 5 files changed, 32 insertions(+), 30 deletions(-)

diff --git a/cputlb.c b/cputlb.c
index aba7e44..e2c95c1 100644
--- a/cputlb.c
+++ b/cputlb.c
@@ -254,7 +254,7 @@ void tlb_set_page(CPUArchState *env, target_ulong vaddr,
     if (size != TARGET_PAGE_SIZE) {
         tlb_add_large_page(env, vaddr, size);
     }
-    section = phys_page_find(address_space_memory.dispatch, paddr >> 
TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, paddr);
 #if defined(DEBUG_TLB)
     printf("tlb_set_page: vaddr=" TARGET_FMT_lx " paddr=0x" TARGET_FMT_plx
            " prot=%x idx=%d pd=0x%08lx\n",
diff --git a/exec.c b/exec.c
index 19725db..53c2778 100644
--- a/exec.c
+++ b/exec.c
@@ -182,7 +182,8 @@ static void phys_page_set(AddressSpaceDispatch *d,
     phys_page_set_level(&d->phys_map, &index, &nb, leaf, P_L2_LEVELS - 1);
 }
 
-MemoryRegionSection *phys_page_find(AddressSpaceDispatch *d, hwaddr index)
+static MemoryRegionSection *phys_page_find(AddressSpaceDispatch *d,
+                                           hwaddr index)
 {
     PhysPageEntry lp = d->phys_map;
     PhysPageEntry *p;
@@ -1894,19 +1895,16 @@ static void invalidate_and_set_dirty(hwaddr addr,
 void address_space_rw(AddressSpace *as, hwaddr addr, uint8_t *buf,
                       int len, bool is_write)
 {
-    AddressSpaceDispatch *d = as->dispatch;
     int l;
     uint8_t *ptr;
     uint32_t val;
-    hwaddr page;
     MemoryRegionSection *section;
 
     while (len > 0) {
-        page = addr & TARGET_PAGE_MASK;
-        l = (page + TARGET_PAGE_SIZE) - addr;
+        l = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - addr;
         if (l > len)
             l = len;
-        section = phys_page_find(d, page >> TARGET_PAGE_BITS);
+        section = address_space_lookup_region(as, addr);
 
         if (is_write) {
             if (!memory_region_is_ram(section->mr)) {
@@ -2006,18 +2004,15 @@ void cpu_physical_memory_rw(hwaddr addr, uint8_t *buf,
 void cpu_physical_memory_write_rom(hwaddr addr,
                                    const uint8_t *buf, int len)
 {
-    AddressSpaceDispatch *d = address_space_memory.dispatch;
     int l;
     uint8_t *ptr;
-    hwaddr page;
     MemoryRegionSection *section;
 
     while (len > 0) {
-        page = addr & TARGET_PAGE_MASK;
-        l = (page + TARGET_PAGE_SIZE) - addr;
+        l = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - addr;
         if (l > len)
             l = len;
-        section = phys_page_find(d, page >> TARGET_PAGE_BITS);
+        section = address_space_lookup_region(&address_space_memory, addr);
 
         if (!(memory_region_is_ram(section->mr) ||
               memory_region_is_romd(section->mr))) {
@@ -2096,22 +2091,19 @@ void *address_space_map(AddressSpace *as,
                         hwaddr *plen,
                         bool is_write)
 {
-    AddressSpaceDispatch *d = as->dispatch;
     hwaddr len = *plen;
     hwaddr todo = 0;
     int l;
-    hwaddr page;
     MemoryRegionSection *section;
     ram_addr_t raddr = RAM_ADDR_MAX;
     ram_addr_t rlen;
     void *ret;
 
     while (len > 0) {
-        page = addr & TARGET_PAGE_MASK;
-        l = (page + TARGET_PAGE_SIZE) - addr;
+        l = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - addr;
         if (l > len)
             l = len;
-        section = phys_page_find(d, page >> TARGET_PAGE_BITS);
+        section = address_space_lookup_region(as, addr);
 
         if (!(memory_region_is_ram(section->mr) && !section->readonly)) {
             if (todo || bounce.buffer) {
@@ -2188,6 +2180,11 @@ void cpu_physical_memory_unmap(void *buffer, hwaddr len,
     return address_space_unmap(&address_space_memory, buffer, len, is_write, 
access_len);
 }
 
+MemoryRegionSection *address_space_lookup_region(AddressSpace *as, hwaddr addr)
+{
+    return phys_page_find(as->dispatch, addr >> TARGET_PAGE_BITS);
+}
+
 /* warning: addr must be aligned */
 static inline uint32_t ldl_phys_internal(hwaddr addr,
                                          enum device_endian endian)
@@ -2196,7 +2193,7 @@ static inline uint32_t ldl_phys_internal(hwaddr addr,
     uint32_t val;
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch, addr >> 
TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, addr);
 
     if (!(memory_region_is_ram(section->mr) ||
           memory_region_is_romd(section->mr))) {
@@ -2255,7 +2252,7 @@ static inline uint64_t ldq_phys_internal(hwaddr addr,
     uint64_t val;
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch, addr >> 
TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, addr);
 
     if (!(memory_region_is_ram(section->mr) ||
           memory_region_is_romd(section->mr))) {
@@ -2322,7 +2319,7 @@ static inline uint32_t lduw_phys_internal(hwaddr addr,
     uint64_t val;
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch, addr >> 
TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, addr);
 
     if (!(memory_region_is_ram(section->mr) ||
           memory_region_is_romd(section->mr))) {
@@ -2381,7 +2378,7 @@ void stl_phys_notdirty(hwaddr addr, uint32_t val)
     uint8_t *ptr;
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch, addr >> 
TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, addr);
 
     if (!memory_region_is_ram(section->mr) || section->readonly) {
         addr = memory_region_section_addr(section, addr);
@@ -2413,7 +2410,7 @@ void stq_phys_notdirty(hwaddr addr, uint64_t val)
     uint8_t *ptr;
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch, addr >> 
TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, addr);
 
     if (!memory_region_is_ram(section->mr) || section->readonly) {
         addr = memory_region_section_addr(section, addr);
@@ -2442,7 +2439,7 @@ static inline void stl_phys_internal(hwaddr addr, 
uint32_t val,
     uint8_t *ptr;
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch, addr >> 
TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, addr);
 
     if (!memory_region_is_ram(section->mr) || section->readonly) {
         addr = memory_region_section_addr(section, addr);
@@ -2509,7 +2506,7 @@ static inline void stw_phys_internal(hwaddr addr, 
uint32_t val,
     uint8_t *ptr;
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch, addr >> 
TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, addr);
 
     if (!memory_region_is_ram(section->mr) || section->readonly) {
         addr = memory_region_section_addr(section, addr);
@@ -2634,8 +2631,7 @@ bool cpu_physical_memory_is_io(hwaddr phys_addr)
 {
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch,
-                             phys_addr >> TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, phys_addr);
 
     return !(memory_region_is_ram(section->mr) ||
              memory_region_is_romd(section->mr));
diff --git a/include/exec/cputlb.h b/include/exec/cputlb.h
index 733c885..f144e6e 100644
--- a/include/exec/cputlb.h
+++ b/include/exec/cputlb.h
@@ -26,8 +26,6 @@ void tlb_unprotect_code_phys(CPUArchState *env, ram_addr_t 
ram_addr,
                              target_ulong vaddr);
 void tlb_reset_dirty_range(CPUTLBEntry *tlb_entry, uintptr_t start,
                            uintptr_t length);
-MemoryRegionSection *phys_page_find(struct AddressSpaceDispatch *d,
-                                    hwaddr index);
 void cpu_tlb_reset_dirty_all(ram_addr_t start1, ram_addr_t length);
 void tlb_set_dirty(CPUArchState *env, target_ulong vaddr);
 extern int tlb_flush_count;
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 9e88320..11ca4e2 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -887,6 +887,15 @@ void *address_space_map(AddressSpace *as, hwaddr addr,
 void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
                          int is_write, hwaddr access_len);
 
+/**
+ * address_space_lookup_region: Looks up memory region corresponding to given
+ *                              access address
+ *
+ * @as: #AddressSpace to be accessed
+ * @addr: address within that address space
+ */
+MemoryRegionSection *address_space_lookup_region(AddressSpace *as,
+                                                 hwaddr addr);
 
 #endif
 
diff --git a/translate-all.c b/translate-all.c
index da93608..078a657 100644
--- a/translate-all.c
+++ b/translate-all.c
@@ -1356,8 +1356,7 @@ void tb_invalidate_phys_addr(hwaddr addr)
     ram_addr_t ram_addr;
     MemoryRegionSection *section;
 
-    section = phys_page_find(address_space_memory.dispatch,
-                             addr >> TARGET_PAGE_BITS);
+    section = address_space_lookup_region(&address_space_memory, addr);
     if (!(memory_region_is_ram(section->mr)
           || (section->mr->rom_device && section->mr->readable))) {
         return;
-- 
1.7.3.4