fix aligned alloc on Windows

Author: mvorisek

Zend/zend_alloc.c

@@ -418,6 +418,14 @@ stderr_last_error(char *msg)
 static void zend_mm_munmap(void *addr, size_t size)
 {
 #ifdef _WIN32
+    MEMORY_BASIC_INFORMATION mbi;
+    if (VirtualQuery(addr, &mbi, sizeof(mbi)) == 0) {
+#if ZEND_MM_ERROR
+		stderr_last_error("VirtualQuery() failed");
+#endif
+    }
+    addr = mbi.AllocationBase;
+    
 	if (VirtualFree(addr, 0, MEM_RELEASE) == 0) {
 #if ZEND_MM_ERROR
 		stderr_last_error("VirtualFree() failed");
@@ -432,54 +440,34 @@ static void zend_mm_munmap(void *addr, size_t size)
 #endif
 }
 
-#ifndef HAVE_MREMAP
-static void *zend_mm_mmap_fixed(void *addr, size_t size)
-{
 #ifdef _WIN32
-	void *ptr = VirtualAlloc(addr, size, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
+static void *zend_mm_mmap_reserve(size_t size)
+{
+	void *ptr = VirtualAlloc(NULL, size, MEM_RESERVE, PAGE_READWRITE);
 	if (ptr == NULL) {
 #if ZEND_MM_ERROR
-		stderr_last_error("VirtualAlloc() failed");
+		stderr_last_error("VirtualAlloc() reserve failed");
 #endif
 		return NULL;
 	}
-    ZEND_ASSERT(ptr == addr);
 	return ptr;
-#else
-	int flags = MAP_PRIVATE | MAP_ANON;
-#if defined(MAP_EXCL)
-	flags |= MAP_FIXED | MAP_EXCL;
-#endif
-	/* MAP_FIXED leads to discarding of the old mapping, so it can't be used. */
-	void *ptr = mmap(addr, size, PROT_READ | PROT_WRITE, flags /*| MAP_POPULATE | MAP_HUGETLB*/, ZEND_MM_FD, 0);
-
-	if (ptr == MAP_FAILED) {
-#if ZEND_MM_ERROR && !defined(MAP_EXCL)
-		fprintf(stderr, "\nmmap() failed: [%d] %s\n", errno, strerror(errno));
-#endif
-		return NULL;
-	} else if (ptr != addr) {
-		zend_mm_munmap(ptr, size);
-		return NULL;
-	}
-	return ptr;
-#endif
 }
-#endif
 
-static void *zend_mm_mmap(size_t size)
+static void *zend_mm_mmap_commit(void *addr, size_t size)
 {
-#ifdef _WIN32
-	void *ptr = VirtualAlloc(NULL, size, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
-
+	void *ptr = VirtualAlloc(addr, size, MEM_COMMIT, PAGE_READWRITE);
 	if (ptr == NULL) {
 #if ZEND_MM_ERROR
-		stderr_last_error("VirtualAlloc() failed");
+        stderr_last_error("VirtualAlloc() commit failed");
 #endif
 		return NULL;
 	}
+    ZEND_ASSERT(ptr == addr);
 	return ptr;
+}
 #else
+static void *zend_mm_mmap(size_t size)
+{
 	void *ptr;
 
 #ifdef MAP_HUGETLB
@@ -492,16 +480,39 @@ static void *zend_mm_mmap(size_t size)
 #endif
 
 	ptr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, ZEND_MM_FD, 0);
-
 	if (ptr == MAP_FAILED) {
 #if ZEND_MM_ERROR
 		fprintf(stderr, "\nmmap() failed: [%d] %s\n", errno, strerror(errno));
 #endif
 		return NULL;
 	}
 	return ptr;
+}
+#endif
+
+#ifndef HAVE_MREMAP
+#ifndef _WIN32
+static void *zend_mm_mmap_fixed(void *addr, size_t size)
+{
+	int flags = MAP_PRIVATE | MAP_ANON;
+#if defined(MAP_EXCL)
+	flags |= MAP_FIXED | MAP_EXCL;
 #endif
+	/* MAP_FIXED leads to discarding of the old mapping, so it can't be used. */
+	void *ptr = mmap(addr, size, PROT_READ | PROT_WRITE, flags /*| MAP_POPULATE | MAP_HUGETLB*/, ZEND_MM_FD, 0);
+	if (ptr == MAP_FAILED) {
+#if ZEND_MM_ERROR && !defined(MAP_EXCL)
+		fprintf(stderr, "\nmmap() failed: [%d] %s\n", errno, strerror(errno));
+#endif
+		return NULL;
+	} else if (ptr != addr) {
+		zend_mm_munmap(ptr, size);
+		return NULL;
+	}
+	return ptr;
 }
+#endif
+#endif
 
 /***********/
 /* Bitmask */
@@ -667,52 +678,44 @@ static zend_always_inline int zend_mm_bitset_is_free_range(zend_mm_bitset *bitse
 
 static void *zend_mm_chunk_alloc_int(size_t size, size_t alignment)
 {
-	void *ptr = zend_mm_mmap(size);
+#ifdef _WIN32
+	void *ptr = zend_mm_mmap_reserve(size + alignment/* - REAL_PAGE_SIZE TODO check if really 4KB */);
+    if (ptr == NULL) {
+		return NULL;
+	}
 
+    size_t offset = ZEND_MM_ALIGNED_OFFSET(ptr, alignment);
+    return zend_mm_mmap_commit((void*)((char*)ptr + (alignment - offset)), size);
+#else
+	void *ptr = zend_mm_mmap(size);
 	if (ptr == NULL) {
 		return NULL;
-	} else if (ZEND_MM_ALIGNED_OFFSET(ptr, alignment) == 0) {
+	}
+
+    if (ZEND_MM_ALIGNED_OFFSET(ptr, alignment) != 0) {
+        zend_mm_munmap(ptr, size);
+        ptr = zend_mm_mmap(size + alignment - REAL_PAGE_SIZE);
+
+        size_t offset = ZEND_MM_ALIGNED_OFFSET(ptr, alignment);
+        if (offset != 0) {
+            offset = alignment - offset;
+            zend_mm_munmap(ptr, offset);
+            ptr = (char*)ptr + offset;
+            alignment -= offset;
+        }
+        if (alignment > REAL_PAGE_SIZE) {
+            zend_mm_munmap((char*)ptr + size, alignment - REAL_PAGE_SIZE);
+        }
+    }
+
 #ifdef MADV_HUGEPAGE
-		if (zend_mm_use_huge_pages) {
-			madvise(ptr, size, MADV_HUGEPAGE);
-		}
+    if (zend_mm_use_huge_pages) {
+        madvise(ptr, size, MADV_HUGEPAGE);
+    }
 #endif
-		return ptr;
-	} else {
-		size_t offset;
 
-		/* chunk has to be aligned */
-		zend_mm_munmap(ptr, size);
-		ptr = zend_mm_mmap(size + alignment - REAL_PAGE_SIZE);
-#ifdef _WIN32
-		offset = ZEND_MM_ALIGNED_OFFSET(ptr, alignment);
-		zend_mm_munmap(ptr, size + alignment - REAL_PAGE_SIZE);
-		ptr = zend_mm_mmap_fixed((void*)((char*)ptr + (alignment - offset)), size);
-		offset = ZEND_MM_ALIGNED_OFFSET(ptr, alignment);
-		if (offset != 0) {
-			zend_mm_munmap(ptr, size);
-			return NULL;
-		}
-		return ptr;
-#else
-		offset = ZEND_MM_ALIGNED_OFFSET(ptr, alignment);
-		if (offset != 0) {
-			offset = alignment - offset;
-			zend_mm_munmap(ptr, offset);
-			ptr = (char*)ptr + offset;
-			alignment -= offset;
-		}
-		if (alignment > REAL_PAGE_SIZE) {
-			zend_mm_munmap((char*)ptr + size, alignment - REAL_PAGE_SIZE);
-		}
-# ifdef MADV_HUGEPAGE
-		if (zend_mm_use_huge_pages) {
-			madvise(ptr, size, MADV_HUGEPAGE);
-		}
-# endif
+    return ptr;
 #endif
-		return ptr;
-	}
 }
 
 static void *zend_mm_chunk_alloc(zend_mm_heap *heap, size_t size, size_t alignment)