[Qemu-devel] [RFC PATCH 3/8] memory: return MemoryRegion from qemu_ram_addr_from_host

[Paolo Bonzini <pbonzini@redhat.com>]

It will be needed in the next patch.

The common parts of qemu_get_ram_ptr and qemu_ram_addr_from_host are
moved to a new function qemu_get_ram_block.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 exec.c                    |   35 +++++++++++++++++++++--------------
 include/exec/cpu-common.h |    2 +-
 target-i386/kvm.c         |    4 ++--
 3 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/exec.c b/exec.c
index 8e46228..54b57fc 100644
--- a/exec.c
+++ b/exec.c
@@ -1287,15 +1287,7 @@ void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)
 }
 #endif /* !_WIN32 */
 
-/* Return a host pointer to ram allocated with qemu_ram_alloc.
-   With the exception of the softmmu code in this file, this should
-   only be used for local memory (e.g. video ram) that the device owns,
-   and knows it isn't going to access beyond the end of the block.
-
-   It should not be used for general purpose DMA.
-   Use cpu_physical_memory_map/cpu_physical_memory_rw instead.
- */
-void *qemu_get_ram_ptr(ram_addr_t addr)
+static RAMBlock *qemu_get_ram_block(ram_addr_t addr)
 {
     RAMBlock *block;
 
@@ -1315,6 +1307,21 @@ void *qemu_get_ram_ptr(ram_addr_t addr)
 
 found:
     ram_list.mru_block = block;
+    return block;
+}
+
+/* Return a host pointer to ram allocated with qemu_ram_alloc.
+   With the exception of the softmmu code in this file, this should
+   only be used for local memory (e.g. video ram) that the device owns,
+   and knows it isn't going to access beyond the end of the block.
+
+   It should not be used for general purpose DMA.
+   Use cpu_physical_memory_map/cpu_physical_memory_rw instead.
+ */
+void *qemu_get_ram_ptr(ram_addr_t addr)
+{
+    RAMBlock *block = qemu_get_ram_block(addr);
+
     if (xen_enabled()) {
         /* We need to check if the requested address is in the RAM
          * because we don't want to map the entire memory in QEMU.
@@ -1394,14 +1401,14 @@ void qemu_put_ram_ptr(void *addr)
     trace_qemu_put_ram_ptr(addr);
 }
 
-int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
+MemoryRegion *qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
 {
     RAMBlock *block;
     uint8_t *host = ptr;
 
     if (xen_enabled()) {
         *ram_addr = xen_ram_addr_from_mapcache(ptr);
-        return 0;
+        return qemu_get_ram_block(*ram_addr)->mr;
     }
 
     block = ram_list.mru_block;
@@ -1419,11 +1426,11 @@ int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
         }
     }
 
-    return -1;
+    return NULL;
 
 found:
     *ram_addr = block->offset + (host - block->host);
-    return 0;
+    return block->mr;
 }
 
 /* Some of the softmmu routines need to translate from a host pointer
@@ -1432,7 +1439,7 @@ ram_addr_t qemu_ram_addr_from_host_nofail(void *ptr)
 {
     ram_addr_t ram_addr;
 
-    if (qemu_ram_addr_from_host(ptr, &ram_addr)) {
+    if (qemu_ram_addr_from_host(ptr, &ram_addr) == NULL) {
         fprintf(stderr, "Bad ram pointer %p\n", ptr);
         abort();
     }
diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
index 2e5f11f..84dfd3b 100644
--- a/include/exec/cpu-common.h
+++ b/include/exec/cpu-common.h
@@ -53,7 +53,7 @@ void qemu_ram_remap(ram_addr_t addr, ram_addr_t length);
 void *qemu_get_ram_ptr(ram_addr_t addr);
 void qemu_put_ram_ptr(void *addr);
 /* This should not be used by devices.  */
-int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr);
+MemoryRegion *qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr);
 ram_addr_t qemu_ram_addr_from_host_nofail(void *ptr);
 void qemu_ram_set_idstr(ram_addr_t addr, const char *name, DeviceState *dev);
 
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 9ffb6ca..7ba98cd 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -318,7 +318,7 @@ int kvm_arch_on_sigbus_vcpu(CPUState *c, int code, void *addr)
 
     if ((env->mcg_cap & MCG_SER_P) && addr
         && (code == BUS_MCEERR_AR || code == BUS_MCEERR_AO)) {
-        if (qemu_ram_addr_from_host(addr, &ram_addr) ||
+        if (qemu_ram_addr_from_host(addr, &ram_addr) == NULL ||
             !kvm_physical_memory_addr_from_host(c->kvm_state, addr, &paddr)) {
             fprintf(stderr, "Hardware memory error for memory used by "
                     "QEMU itself instead of guest system!\n");
@@ -350,7 +350,7 @@ int kvm_arch_on_sigbus(int code, void *addr)
         hwaddr paddr;
 
         /* Hope we are lucky for AO MCE */
-        if (qemu_ram_addr_from_host(addr, &ram_addr) ||
+        if (qemu_ram_addr_from_host(addr, &ram_addr) == NULL ||
             !kvm_physical_memory_addr_from_host(CPU(first_cpu)->kvm_state,
                                                 addr, &paddr)) {
             fprintf(stderr, "Hardware memory error for memory used by "
-- 
1.7.1