[Qemu-devel] [PATCH 1/2] RAMBlocks: Store page size

[Dr. David Alan Gilbert (git)]

From: "Dr. David Alan Gilbert" <address@hidden>

Store the page size in each RAMBlock, we need it later.

Signed-off-by: Dr. David Alan Gilbert <address@hidden>
---
 exec.c                    | 17 +++++++++++------
 include/exec/cpu-common.h |  1 +
 include/exec/ram_addr.h   |  1 +
 3 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/exec.c b/exec.c
index c8389f9..e111323 100644
--- a/exec.c
+++ b/exec.c
@@ -1201,7 +1201,6 @@ static void *file_ram_alloc(RAMBlock *block,
     char *c;
     void *area = MAP_FAILED;
     int fd = -1;
-    int64_t page_size;
 
     if (kvm_enabled() && !kvm_has_sync_mmu()) {
         error_setg(errp,
@@ -1256,17 +1255,17 @@ static void *file_ram_alloc(RAMBlock *block,
          */
     }
 
-    page_size = qemu_fd_getpagesize(fd);
-    block->mr->align = MAX(page_size, QEMU_VMALLOC_ALIGN);
+    block->page_size = qemu_fd_getpagesize(fd);
+    block->mr->align = MAX(block->page_size, QEMU_VMALLOC_ALIGN);
 
-    if (memory < page_size) {
+    if (memory < block->page_size) {
         error_setg(errp, "memory size 0x" RAM_ADDR_FMT " must be equal to "
                    "or larger than page size 0x%" PRIx64,
-                   memory, page_size);
+                   memory, block->page_size);
         goto error;
     }
 
-    memory = ROUND_UP(memory, page_size);
+    memory = ROUND_UP(memory, block->page_size);
 
     /*
      * ftruncate is not supported by hugetlbfs in older
@@ -1421,6 +1420,11 @@ void qemu_ram_unset_idstr(RAMBlock *block)
     }
 }
 
+size_t qemu_ram_pagesize(RAMBlock *rb)
+{
+    return rb->page_size;
+}
+
 static int memory_try_enable_merging(void *addr, size_t len)
 {
     if (!machine_mem_merge(current_machine)) {
@@ -1660,6 +1664,7 @@ RAMBlock *qemu_ram_alloc_internal(ram_addr_t size, 
ram_addr_t max_size,
     new_block->max_length = max_size;
     assert(max_size >= size);
     new_block->fd = -1;
+    new_block->page_size = getpagesize();
     new_block->host = host;
     if (host) {
         new_block->flags |= RAM_PREALLOC;
diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
index 869ba41..cffdc13 100644
--- a/include/exec/cpu-common.h
+++ b/include/exec/cpu-common.h
@@ -63,6 +63,7 @@ RAMBlock *qemu_ram_block_from_host(void *ptr, bool 
round_offset,
 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);
+size_t qemu_ram_pagesize(RAMBlock *block);
 
 void cpu_physical_memory_rw(hwaddr addr, uint8_t *buf,
                             int len, int is_write);
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 2a9465d..54d7108 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -36,6 +36,7 @@ struct RAMBlock {
     /* RCU-enabled, writes protected by the ramlist lock */
     QLIST_ENTRY(RAMBlock) next;
     int fd;
+    size_t page_size;
 };
 
 static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
-- 
2.7.4