[PATCH v2 0/4] system/memory: Constify various RAMBlock/MemoryRegion arguments

[PATCH v2 0/4] system/memory: Constify various RAMBlock/MemoryRegion arguments

[Philippe Mathieu-Daudé]

v2:
- Dropped "stubs: Merge physmem.c within ram-block.c" (Zoltan)
- Dropped "info mtree" patches (no time to update doc for freeze)
- New Xen patch

Philippe Mathieu-Daudé (4):
  system/ramblock: Constify various RAMBlock arguments
  system/memory: Constify various MemoryRegion arguments
  system/xen: Constify various MemoryRegion arguments
  system/memory: Have memory_region_type() correctly describe containers

 include/system/memory.h       | 38 ++++++++++++++++-----------------
 include/system/ramblock.h     | 28 ++++++++++++------------
 include/system/xen-mapcache.h |  2 +-
 include/system/xen.h          |  6 +++---
 hw/xen/xen-hvm-common.c       |  8 +++----
 hw/xen/xen-mapcache.c         |  2 +-
 hw/xen/xen_stubs.c            |  6 +++---
 stubs/physmem.c               |  2 +-
 stubs/ram-block.c             |  6 +++---
 system/memory.c               | 40 +++++++++++++++++++----------------
 system/physmem.c              | 30 +++++++++++++-------------
 11 files changed, 86 insertions(+), 82 deletions(-)

-- 
2.53.0

[PATCH v2 1/4] system/ramblock: Constify various RAMBlock arguments

[Philippe Mathieu-Daudé]

Mark the RAMBlock structure const when is only accessed read-only.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
 include/system/ramblock.h | 28 ++++++++++++++--------------
 stubs/physmem.c           |  2 +-
 stubs/ram-block.c         |  6 +++---
 system/physmem.c          | 28 ++++++++++++++--------------
 4 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/include/system/ramblock.h b/include/system/ramblock.h
index e9f58ac0457..4435f8d55fe 100644
--- a/include/system/ramblock.h
+++ b/include/system/ramblock.h
@@ -154,26 +154,26 @@ RAMBlock *qemu_ram_block_by_name(const char *name);
  */
 RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset,
                                    ram_addr_t *offset);
-ram_addr_t qemu_ram_block_host_offset(RAMBlock *rb, void *host);
+ram_addr_t qemu_ram_block_host_offset(const RAMBlock *rb, void *host);
 void qemu_ram_set_idstr(RAMBlock *block, const char *name, DeviceState *dev);
 void qemu_ram_unset_idstr(RAMBlock *block);
-const char *qemu_ram_get_idstr(RAMBlock *rb);
-void *qemu_ram_get_host_addr(RAMBlock *rb);
-ram_addr_t qemu_ram_get_offset(RAMBlock *rb);
-ram_addr_t qemu_ram_get_fd_offset(RAMBlock *rb);
-ram_addr_t qemu_ram_get_used_length(RAMBlock *rb);
-ram_addr_t qemu_ram_get_max_length(RAMBlock *rb);
-bool qemu_ram_is_shared(RAMBlock *rb);
-bool qemu_ram_is_noreserve(RAMBlock *rb);
-bool qemu_ram_is_uf_zeroable(RAMBlock *rb);
+const char *qemu_ram_get_idstr(const RAMBlock *rb);
+void *qemu_ram_get_host_addr(const RAMBlock *rb);
+ram_addr_t qemu_ram_get_offset(const RAMBlock *rb);
+ram_addr_t qemu_ram_get_fd_offset(const RAMBlock *rb);
+ram_addr_t qemu_ram_get_used_length(const RAMBlock *rb);
+ram_addr_t qemu_ram_get_max_length(const RAMBlock *rb);
+bool qemu_ram_is_shared(const RAMBlock *rb);
+bool qemu_ram_is_noreserve(const RAMBlock *rb);
+bool qemu_ram_is_uf_zeroable(const RAMBlock *rb);
 void qemu_ram_set_uf_zeroable(RAMBlock *rb);
-bool qemu_ram_is_migratable(RAMBlock *rb);
+bool qemu_ram_is_migratable(const RAMBlock *rb);
 void qemu_ram_set_migratable(RAMBlock *rb);
 void qemu_ram_unset_migratable(RAMBlock *rb);
-bool qemu_ram_is_named_file(RAMBlock *rb);
-int qemu_ram_get_fd(RAMBlock *rb);
+bool qemu_ram_is_named_file(const RAMBlock *rb);
+int qemu_ram_get_fd(const RAMBlock *rb);
 
-size_t qemu_ram_pagesize(RAMBlock *block);
+size_t qemu_ram_pagesize(const RAMBlock *block);
 size_t qemu_ram_pagesize_largest(void);
 #include "exec/target_page.h"
 #include "exec/hwaddr.h"
diff --git a/stubs/physmem.c b/stubs/physmem.c
index 14667f2bd8f..2eca06ab6d6 100644
--- a/stubs/physmem.c
+++ b/stubs/physmem.c
@@ -7,7 +7,7 @@ RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset,
     return NULL;
 }
 
-int qemu_ram_get_fd(RAMBlock *rb)
+int qemu_ram_get_fd(const RAMBlock *rb)
 {
     return -1;
 }
diff --git a/stubs/ram-block.c b/stubs/ram-block.c
index 8790a59593e..1c79e447ff0 100644
--- a/stubs/ram-block.c
+++ b/stubs/ram-block.c
@@ -3,17 +3,17 @@
 #include "system/ramblock.h"
 #include "system/memory.h"
 
-void *qemu_ram_get_host_addr(RAMBlock *rb)
+void *qemu_ram_get_host_addr(const RAMBlock *rb)
 {
     return 0;
 }
 
-ram_addr_t qemu_ram_get_offset(RAMBlock *rb)
+ram_addr_t qemu_ram_get_offset(const RAMBlock *rb)
 {
     return 0;
 }
 
-ram_addr_t qemu_ram_get_used_length(RAMBlock *rb)
+ram_addr_t qemu_ram_get_used_length(const RAMBlock *rb)
 {
     return 0;
 }
diff --git a/system/physmem.c b/system/physmem.c
index 7eecd818770..e5390d09bef 100644
--- a/system/physmem.c
+++ b/system/physmem.c
@@ -1859,48 +1859,48 @@ static void qemu_ram_setup_dump(void *addr, ram_addr_t size)
     }
 }
 
-const char *qemu_ram_get_idstr(RAMBlock *rb)
+const char *qemu_ram_get_idstr(const RAMBlock *rb)
 {
     return rb->idstr;
 }
 
-void *qemu_ram_get_host_addr(RAMBlock *rb)
+void *qemu_ram_get_host_addr(const RAMBlock *rb)
 {
     return rb->host;
 }
 
-ram_addr_t qemu_ram_get_offset(RAMBlock *rb)
+ram_addr_t qemu_ram_get_offset(const RAMBlock *rb)
 {
     return rb->offset;
 }
 
-ram_addr_t qemu_ram_get_fd_offset(RAMBlock *rb)
+ram_addr_t qemu_ram_get_fd_offset(const RAMBlock *rb)
 {
     return rb->fd_offset;
 }
 
-ram_addr_t qemu_ram_get_used_length(RAMBlock *rb)
+ram_addr_t qemu_ram_get_used_length(const RAMBlock *rb)
 {
     return rb->used_length;
 }
 
-ram_addr_t qemu_ram_get_max_length(RAMBlock *rb)
+ram_addr_t qemu_ram_get_max_length(const RAMBlock *rb)
 {
     return rb->max_length;
 }
 
-bool qemu_ram_is_shared(RAMBlock *rb)
+bool qemu_ram_is_shared(const RAMBlock *rb)
 {
     return rb->flags & RAM_SHARED;
 }
 
-bool qemu_ram_is_noreserve(RAMBlock *rb)
+bool qemu_ram_is_noreserve(const RAMBlock *rb)
 {
     return rb->flags & RAM_NORESERVE;
 }
 
 /* Note: Only set at the start of postcopy */
-bool qemu_ram_is_uf_zeroable(RAMBlock *rb)
+bool qemu_ram_is_uf_zeroable(const RAMBlock *rb)
 {
     return rb->flags & RAM_UF_ZEROPAGE;
 }
@@ -1910,7 +1910,7 @@ void qemu_ram_set_uf_zeroable(RAMBlock *rb)
     rb->flags |= RAM_UF_ZEROPAGE;
 }
 
-bool qemu_ram_is_migratable(RAMBlock *rb)
+bool qemu_ram_is_migratable(const RAMBlock *rb)
 {
     return rb->flags & RAM_MIGRATABLE;
 }
@@ -1925,12 +1925,12 @@ void qemu_ram_unset_migratable(RAMBlock *rb)
     rb->flags &= ~RAM_MIGRATABLE;
 }
 
-bool qemu_ram_is_named_file(RAMBlock *rb)
+bool qemu_ram_is_named_file(const RAMBlock *rb)
 {
     return rb->flags & RAM_NAMED_FILE;
 }
 
-int qemu_ram_get_fd(RAMBlock *rb)
+int qemu_ram_get_fd(const RAMBlock *rb)
 {
     return rb->fd;
 }
@@ -1987,7 +1987,7 @@ static char *cpr_name(MemoryRegion *mr)
     }
 }
 
-size_t qemu_ram_pagesize(RAMBlock *rb)
+size_t qemu_ram_pagesize(const RAMBlock *rb)
 {
     return rb->page_size;
 }
@@ -2772,7 +2772,7 @@ void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr)
 }
 
 /* Return the offset of a hostpointer within a ramblock */
-ram_addr_t qemu_ram_block_host_offset(RAMBlock *rb, void *host)
+ram_addr_t qemu_ram_block_host_offset(const RAMBlock *rb, void *host)
 {
     ram_addr_t res = (uint8_t *)host - (uint8_t *)rb->host;
     assert((uintptr_t)host >= (uintptr_t)rb->host);
-- 
2.53.0

[PATCH v2 2/4] system/memory: Constify various MemoryRegion arguments

[Philippe Mathieu-Daudé]

Mark the MemoryRegion structure const when is only accessed read-only.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
 include/system/memory.h | 38 +++++++++++++++++++-------------------
 system/memory.c         | 38 ++++++++++++++++++++------------------
 system/physmem.c        |  2 +-
 3 files changed, 40 insertions(+), 38 deletions(-)

diff --git a/include/system/memory.h b/include/system/memory.h
index 0562af31361..6a04c46db37 100644
--- a/include/system/memory.h
+++ b/include/system/memory.h
@@ -1749,14 +1749,14 @@ bool memory_region_init_rom_device(MemoryRegion *mr,
  *
  * @mr: the memory region being queried.
  */
-Object *memory_region_owner(MemoryRegion *mr);
+Object *memory_region_owner(const MemoryRegion *mr);
 
 /**
  * memory_region_size: get a memory region's size.
  *
  * @mr: the memory region being queried.
  */
-uint64_t memory_region_size(MemoryRegion *mr);
+uint64_t memory_region_size(const MemoryRegion *mr);
 
 /**
  * memory_region_is_ram: check whether a memory region is random access
@@ -1765,7 +1765,7 @@ uint64_t memory_region_size(MemoryRegion *mr);
  *
  * @mr: the memory region being queried
  */
-static inline bool memory_region_is_ram(MemoryRegion *mr)
+static inline bool memory_region_is_ram(const MemoryRegion *mr)
 {
     return mr->ram;
 }
@@ -1777,7 +1777,7 @@ static inline bool memory_region_is_ram(MemoryRegion *mr)
  *
  * @mr: the memory region being queried
  */
-bool memory_region_is_ram_device(MemoryRegion *mr);
+bool memory_region_is_ram_device(const MemoryRegion *mr);
 
 /**
  * memory_region_is_romd: check whether a memory region is in ROMD mode
@@ -1787,7 +1787,7 @@ bool memory_region_is_ram_device(MemoryRegion *mr);
  *
  * @mr: the memory region being queried
  */
-static inline bool memory_region_is_romd(MemoryRegion *mr)
+static inline bool memory_region_is_romd(const MemoryRegion *mr)
 {
     return mr->rom_device && mr->romd_mode;
 }
@@ -1800,7 +1800,7 @@ static inline bool memory_region_is_romd(MemoryRegion *mr)
  *
  * @mr: the memory region being queried
  */
-bool memory_region_is_protected(MemoryRegion *mr);
+bool memory_region_is_protected(const MemoryRegion *mr);
 
 /**
  * memory_region_has_guest_memfd: check whether a memory region has guest_memfd
@@ -1810,7 +1810,7 @@ bool memory_region_is_protected(MemoryRegion *mr);
  *
  * @mr: the memory region being queried
  */
-bool memory_region_has_guest_memfd(MemoryRegion *mr);
+bool memory_region_has_guest_memfd(const MemoryRegion *mr);
 
 /**
  * memory_region_get_iommu: check whether a memory region is an iommu
@@ -1820,7 +1820,7 @@ bool memory_region_has_guest_memfd(MemoryRegion *mr);
  *
  * @mr: the memory region being queried
  */
-static inline IOMMUMemoryRegion *memory_region_get_iommu(MemoryRegion *mr)
+static inline IOMMUMemoryRegion *memory_region_get_iommu(const MemoryRegion *mr)
 {
     if (mr->alias) {
         return memory_region_get_iommu(mr->alias);
@@ -1991,7 +1991,7 @@ const char *memory_region_name(const MemoryRegion *mr);
  * @mr: the memory region being queried
  * @client: the client being queried
  */
-bool memory_region_is_logging(MemoryRegion *mr, uint8_t client);
+bool memory_region_is_logging(const MemoryRegion *mr, uint8_t client);
 
 /**
  * memory_region_get_dirty_log_mask: return the clients for which a
@@ -2002,7 +2002,7 @@ bool memory_region_is_logging(MemoryRegion *mr, uint8_t client);
  *
  * @mr: the memory region being queried
  */
-uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr);
+uint8_t memory_region_get_dirty_log_mask(const MemoryRegion *mr);
 
 /**
  * memory_region_is_rom: check whether a memory region is ROM
@@ -2011,7 +2011,7 @@ uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr);
  *
  * @mr: the memory region being queried
  */
-static inline bool memory_region_is_rom(MemoryRegion *mr)
+static inline bool memory_region_is_rom(const MemoryRegion *mr)
 {
     return mr->ram && mr->readonly;
 }
@@ -2023,7 +2023,7 @@ static inline bool memory_region_is_rom(MemoryRegion *mr)
  *
  * @mr: the memory region being queried
  */
-static inline bool memory_region_is_nonvolatile(MemoryRegion *mr)
+static inline bool memory_region_is_nonvolatile(const MemoryRegion *mr)
 {
     return mr->nonvolatile;
 }
@@ -2036,7 +2036,7 @@ static inline bool memory_region_is_nonvolatile(MemoryRegion *mr)
  *
  * @mr: the RAM or alias memory region being queried.
  */
-int memory_region_get_fd(MemoryRegion *mr);
+int memory_region_get_fd(const MemoryRegion *mr);
 
 /**
  * memory_region_from_host: Convert a pointer into a RAM memory region
@@ -2071,7 +2071,7 @@ MemoryRegion *memory_region_from_host(void *ptr, ram_addr_t *offset);
  *
  * @mr: the memory region being queried.
  */
-void *memory_region_get_ram_ptr(MemoryRegion *mr);
+void *memory_region_get_ram_ptr(const MemoryRegion *mr);
 
 /* memory_region_ram_resize: Resize a RAM region.
  *
@@ -2421,7 +2421,7 @@ void memory_region_add_subregion_overlap(MemoryRegion *mr,
  *
  * @mr: the region to be queried
  */
-ram_addr_t memory_region_get_ram_addr(MemoryRegion *mr);
+ram_addr_t memory_region_get_ram_addr(const MemoryRegion *mr);
 
 uint64_t memory_region_get_alignment(const MemoryRegion *mr);
 /**
@@ -2521,7 +2521,7 @@ bool memory_region_present(MemoryRegion *container, hwaddr addr);
  *
  * @mr: a #MemoryRegion which should be checked if it's mapped
  */
-bool memory_region_is_mapped(MemoryRegion *mr);
+bool memory_region_is_mapped(const MemoryRegion *mr);
 
 /**
  * memory_region_get_ram_discard_manager: get the #RamDiscardManager for a
@@ -2967,7 +2967,7 @@ void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr);
 int memory_access_size(MemoryRegion *mr, unsigned l, hwaddr addr);
 bool prepare_mmio_access(MemoryRegion *mr);
 
-static inline bool memory_region_supports_direct_access(MemoryRegion *mr)
+static inline bool memory_region_supports_direct_access(const MemoryRegion *mr)
 {
     /* ROM DEVICE regions only allow direct access if in ROMD mode. */
     if (memory_region_is_romd(mr)) {
@@ -2984,8 +2984,8 @@ static inline bool memory_region_supports_direct_access(MemoryRegion *mr)
     return !memory_region_is_ram_device(mr);
 }
 
-static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write,
-                                           MemTxAttrs attrs)
+static inline bool memory_access_is_direct(const MemoryRegion *mr,
+                                           bool is_write, MemTxAttrs attrs)
 {
     if (!memory_region_supports_direct_access(mr)) {
         return false;
diff --git a/system/memory.c b/system/memory.c
index c51d0798a84..b130d956d4e 100644
--- a/system/memory.c
+++ b/system/memory.c
@@ -1819,9 +1819,9 @@ static void memory_region_finalize(Object *obj)
     g_free(mr->ioeventfds);
 }
 
-Object *memory_region_owner(MemoryRegion *mr)
+Object *memory_region_owner(const MemoryRegion *mr)
 {
-    Object *obj = OBJECT(mr);
+    const Object *obj = OBJECT(mr);
     return obj->parent;
 }
 
@@ -1849,7 +1849,7 @@ void memory_region_unref(MemoryRegion *mr)
     }
 }
 
-uint64_t memory_region_size(MemoryRegion *mr)
+uint64_t memory_region_size(const MemoryRegion *mr)
 {
     if (int128_eq(mr->size, int128_2_64())) {
         return UINT64_MAX;
@@ -1866,25 +1866,25 @@ const char *memory_region_name(const MemoryRegion *mr)
     return mr->name;
 }
 
-bool memory_region_is_ram_device(MemoryRegion *mr)
+bool memory_region_is_ram_device(const MemoryRegion *mr)
 {
     return mr->ram_device;
 }
 
-bool memory_region_is_protected(MemoryRegion *mr)
+bool memory_region_is_protected(const MemoryRegion *mr)
 {
     return mr->ram && (mr->ram_block->flags & RAM_PROTECTED);
 }
 
-bool memory_region_has_guest_memfd(MemoryRegion *mr)
+bool memory_region_has_guest_memfd(const MemoryRegion *mr)
 {
     return mr->ram_block && mr->ram_block->guest_memfd >= 0;
 }
 
-uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr)
+uint8_t memory_region_get_dirty_log_mask(const MemoryRegion *mr)
 {
     uint8_t mask = mr->dirty_log_mask;
-    RAMBlock *rb = mr->ram_block;
+    const RAMBlock *rb = mr->ram_block;
 
     if (global_dirty_tracking && ((rb && qemu_ram_is_migratable(rb)) ||
                              memory_region_is_iommu(mr))) {
@@ -1898,7 +1898,7 @@ uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr)
     return mask;
 }
 
-bool memory_region_is_logging(MemoryRegion *mr, uint8_t client)
+bool memory_region_is_logging(const MemoryRegion *mr, uint8_t client)
 {
     return memory_region_get_dirty_log_mask(mr) & (1 << client);
 }
@@ -2406,7 +2406,7 @@ void memory_region_reset_dirty(MemoryRegion *mr, hwaddr addr,
         memory_region_get_ram_addr(mr) + addr, size, client, NULL);
 }
 
-int memory_region_get_fd(MemoryRegion *mr)
+int memory_region_get_fd(const MemoryRegion *mr)
 {
     RCU_READ_LOCK_GUARD();
     while (mr->alias) {
@@ -2415,7 +2415,7 @@ int memory_region_get_fd(MemoryRegion *mr)
     return mr->ram_block->fd;
 }
 
-void *memory_region_get_ram_ptr(MemoryRegion *mr)
+void *memory_region_get_ram_ptr(const MemoryRegion *mr)
 {
     uint64_t offset = 0;
 
@@ -2440,7 +2440,7 @@ MemoryRegion *memory_region_from_host(void *ptr, ram_addr_t *offset)
     return block->mr;
 }
 
-ram_addr_t memory_region_get_ram_addr(MemoryRegion *mr)
+ram_addr_t memory_region_get_ram_addr(const MemoryRegion *mr)
 {
     return mr->ram_block ? mr->ram_block->offset : RAM_ADDR_INVALID;
 }
@@ -2806,7 +2806,7 @@ static FlatRange *flatview_lookup(FlatView *view, AddrRange addr)
                    sizeof(FlatRange), cmp_flatrange_addr);
 }
 
-bool memory_region_is_mapped(MemoryRegion *mr)
+bool memory_region_is_mapped(const MemoryRegion *mr)
 {
     return !!mr->container || mr->mapped_via_alias;
 }
@@ -3290,7 +3290,7 @@ void address_space_destroy_free(AddressSpace *as)
     call_rcu(as, do_address_space_destroy_free, rcu);
 }
 
-static const char *memory_region_type(MemoryRegion *mr)
+static const char *memory_region_type(const MemoryRegion *mr)
 {
     if (mr->alias) {
         return memory_region_type(mr->alias);
@@ -3483,7 +3483,6 @@ static void mtree_print_flatview(gpointer key, gpointer value,
     GArray *fv_address_spaces = value;
     struct FlatViewInfo *fvi = user_data;
     FlatRange *range = &view->ranges[0];
-    MemoryRegion *mr;
     int n = view->nr;
     int i;
     AddressSpace *as;
@@ -3510,7 +3509,8 @@ static void mtree_print_flatview(gpointer key, gpointer value,
     }
 
     while (n--) {
-        mr = range->mr;
+        const MemoryRegion *mr = range->mr;
+
         if (range->offset_in_region) {
             qemu_printf(MTREE_INDENT HWADDR_FMT_plx "-" HWADDR_FMT_plx
                         " (prio %d, %s%s): %s @" HWADDR_FMT_plx,
@@ -3683,8 +3683,10 @@ static void mtree_info_as(bool dispatch_tree, bool owner, bool disabled)
 
     /* print aliased regions */
     QTAILQ_FOREACH(ml, &ml_head, mrqueue) {
-        qemu_printf("memory-region: %s\n", memory_region_name(ml->mr));
-        mtree_print_mr(ml->mr, 1, 0, &ml_head, owner, disabled);
+        const MemoryRegion *mr = ml->mr;
+
+        qemu_printf("memory-region: %s\n", memory_region_name(mr));
+        mtree_print_mr(mr, 1, 0, &ml_head, owner, disabled);
         qemu_printf("\n");
     }
 
diff --git a/system/physmem.c b/system/physmem.c
index e5390d09bef..4a9e0760045 100644
--- a/system/physmem.c
+++ b/system/physmem.c
@@ -1975,7 +1975,7 @@ void qemu_ram_unset_idstr(RAMBlock *block)
     }
 }
 
-static char *cpr_name(MemoryRegion *mr)
+static char *cpr_name(const MemoryRegion *mr)
 {
     const char *mr_name = memory_region_name(mr);
     g_autofree char *id = mr->dev ? qdev_get_dev_path(mr->dev) : NULL;
-- 
2.53.0

[PATCH v2 3/4] system/xen: Constify various MemoryRegion arguments

[Philippe Mathieu-Daudé]

Mark the MemoryRegion structure const when is only accessed read-only.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 include/system/xen-mapcache.h | 2 +-
 include/system/xen.h          | 6 +++---
 hw/xen/xen-hvm-common.c       | 8 ++++----
 hw/xen/xen-mapcache.c         | 2 +-
 hw/xen/xen_stubs.c            | 6 +++---
 5 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/include/system/xen-mapcache.h b/include/system/xen-mapcache.h
index c46190dd0ce..114d1929c80 100644
--- a/include/system/xen-mapcache.h
+++ b/include/system/xen-mapcache.h
@@ -16,7 +16,7 @@ typedef hwaddr (*phys_offset_to_gaddr_t)(hwaddr phys_offset,
 bool xen_map_cache_enabled(void);
 void xen_map_cache_init(phys_offset_to_gaddr_t f,
                         void *opaque);
-uint8_t *xen_map_cache(MemoryRegion *mr, hwaddr phys_addr, hwaddr size,
+uint8_t *xen_map_cache(const MemoryRegion *mr, hwaddr phys_addr, hwaddr size,
                        ram_addr_t ram_addr_offset,
                        uint8_t lock, bool dma,
                        bool is_write);
diff --git a/include/system/xen.h b/include/system/xen.h
index 9a7c53f2838..43b857e4d15 100644
--- a/include/system/xen.h
+++ b/include/system/xen.h
@@ -30,7 +30,7 @@ extern bool xen_allowed;
 
 void xen_hvm_modified_memory(ram_addr_t start, ram_addr_t length);
 void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
-                   struct MemoryRegion *mr, Error **errp);
-bool xen_mr_is_memory(MemoryRegion *mr);
-bool xen_mr_is_grants(MemoryRegion *mr);
+                   const MemoryRegion *mr, Error **errp);
+bool xen_mr_is_memory(const MemoryRegion *mr);
+bool xen_mr_is_grants(const MemoryRegion *mr);
 #endif
diff --git a/hw/xen/xen-hvm-common.c b/hw/xen/xen-hvm-common.c
index eb7f6270a0d..62d88804c43 100644
--- a/hw/xen/xen-hvm-common.c
+++ b/hw/xen/xen-hvm-common.c
@@ -23,19 +23,19 @@
 MemoryRegion xen_memory, xen_grants;
 
 /* Check for any kind of xen memory, foreign mappings or grants.  */
-bool xen_mr_is_memory(MemoryRegion *mr)
+bool xen_mr_is_memory(const MemoryRegion *mr)
 {
     return mr == &xen_memory || mr == &xen_grants;
 }
 
 /* Check specifically for grants.  */
-bool xen_mr_is_grants(MemoryRegion *mr)
+bool xen_mr_is_grants(const MemoryRegion *mr)
 {
     return mr == &xen_grants;
 }
 
-void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr,
-                   Error **errp)
+void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
+                   const MemoryRegion *mr, Error **errp)
 {
     unsigned target_page_bits = qemu_target_page_bits();
     unsigned long nr_pfn;
diff --git a/hw/xen/xen-mapcache.c b/hw/xen/xen-mapcache.c
index a3c162cd4c6..85cf0cf359c 100644
--- a/hw/xen/xen-mapcache.c
+++ b/hw/xen/xen-mapcache.c
@@ -460,7 +460,7 @@ tryagain:
     return mc->last_entry->vaddr_base + address_offset;
 }
 
-uint8_t *xen_map_cache(MemoryRegion *mr,
+uint8_t *xen_map_cache(const MemoryRegion *mr,
                        hwaddr phys_addr, hwaddr size,
                        ram_addr_t ram_addr_offset,
                        uint8_t lock, bool dma,
diff --git a/hw/xen/xen_stubs.c b/hw/xen/xen_stubs.c
index a39efb5062d..f830768d998 100644
--- a/hw/xen/xen_stubs.c
+++ b/hw/xen/xen_stubs.c
@@ -19,12 +19,12 @@ void xen_hvm_modified_memory(ram_addr_t start, ram_addr_t length)
 }
 
 void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
-                   struct MemoryRegion *mr, Error **errp)
+                   const MemoryRegion *mr, Error **errp)
 {
     g_assert_not_reached();
 }
 
-bool xen_mr_is_memory(MemoryRegion *mr)
+bool xen_mr_is_memory(const MemoryRegion *mr)
 {
     g_assert_not_reached();
 }
@@ -44,7 +44,7 @@ ram_addr_t xen_ram_addr_from_mapcache(void *ptr)
     g_assert_not_reached();
 }
 
-uint8_t *xen_map_cache(MemoryRegion *mr,
+uint8_t *xen_map_cache(const MemoryRegion *mr,
                        hwaddr phys_addr,
                        hwaddr size,
                        ram_addr_t ram_addr_offset,
-- 
2.53.0

[PATCH v2 4/4] system/memory: Have memory_region_type() correctly describe containers

[Philippe Mathieu-Daudé]

MemoryRegion containers are not I/O regions,
describe them as 'container'.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
 system/memory.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/system/memory.c b/system/memory.c
index b130d956d4e..2f2f96ab046 100644
--- a/system/memory.c
+++ b/system/memory.c
@@ -3303,6 +3303,8 @@ static const char *memory_region_type(const MemoryRegion *mr)
         return "rom";
     } else if (memory_region_is_ram(mr)) {
         return "ram";
+    } else if (!mr->container) {
+        return "container";
     } else {
         return "i/o";
     }
-- 
2.53.0

Re: [PATCH v2 3/4] system/xen: Constify various MemoryRegion arguments

[Pierrick Bouvier]

On 3/9/26 11:35 AM, Philippe Mathieu-Daudé wrote:
> Mark the MemoryRegion structure const when is only accessed read-only.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   include/system/xen-mapcache.h | 2 +-
>   include/system/xen.h          | 6 +++---
>   hw/xen/xen-hvm-common.c       | 8 ++++----
>   hw/xen/xen-mapcache.c         | 2 +-
>   hw/xen/xen_stubs.c            | 6 +++---
>   5 files changed, 12 insertions(+), 12 deletions(-)
> 

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>

Re: [PATCH v2 0/4] system/memory: Constify various RAMBlock/MemoryRegion arguments

[Peter Xu]

On Mon, Mar 09, 2026 at 07:35:31PM +0100, Philippe Mathieu-Daudé wrote:
> v2:
> - Dropped "stubs: Merge physmem.c within ram-block.c" (Zoltan)
> - Dropped "info mtree" patches (no time to update doc for freeze)
> - New Xen patch
> 
> Philippe Mathieu-Daudé (4):
>   system/ramblock: Constify various RAMBlock arguments
>   system/memory: Constify various MemoryRegion arguments
>   system/xen: Constify various MemoryRegion arguments
>   system/memory: Have memory_region_type() correctly describe containers

queued

-- 
Peter Xu