From: notaz <notasas@gmail.com>
Date: Tue, 28 Aug 2012 22:56:20 +0000 (+0000)
Subject: extend mmap wrapper functionality
X-Git-Tag: v1.85~101
X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9f3bc846553d02a0d860eb18ea6cf41fabff9557;p=picodrive.git

extend mmap wrapper functionality

git-svn-id: file:///home/notaz/opt/svn/PicoDrive@960 be3aeb3a-fb24-0410-a615-afba39da0efa
---

diff --git a/platform/linux/plat.c b/platform/linux/plat.c
index b7152b55..4ed1e65d 100644
--- a/platform/linux/plat.c
+++ b/platform/linux/plat.c
@@ -17,9 +17,17 @@
 #include <time.h>
 #include <unistd.h>
 #include <sys/mman.h>
+#include <errno.h>
 
 #include "../common/plat.h"
 
+/* XXX: maybe unhardcode pagesize? */
+#define HUGETLB_PAGESIZE (2 * 1024 * 1024)
+#define HUGETLB_THRESHOLD (HUGETLB_PAGESIZE / 2)
+#ifndef MAP_HUGETLB
+#define MAP_HUGETLB 0x40000 /* arch specific */
+#endif
+
 
 int plat_is_dir(const char *path)
 {
@@ -126,16 +134,36 @@ int plat_wait_event(int *fds_hnds, int count, int timeout_ms)
 	return ret;
 }
 
-void *plat_mmap(unsigned long addr, size_t size)
+void *plat_mmap(unsigned long addr, size_t size, int need_exec, int is_fixed)
 {
+	static int hugetlb_disabled;
+	int prot = PROT_READ | PROT_WRITE;
+	int flags = MAP_PRIVATE | MAP_ANONYMOUS;
 	void *req, *ret;
 
 	req = (void *)addr;
-	ret = mmap(req, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+	if (need_exec)
+		prot |= PROT_EXEC;
+	if (is_fixed)
+		flags |= MAP_FIXED;
+	if (size >= HUGETLB_THRESHOLD && !hugetlb_disabled)
+		flags |= MAP_HUGETLB;
+
+	ret = mmap(req, size, prot, flags, -1, 0);
+	if (ret == MAP_FAILED && (flags & MAP_HUGETLB)) {
+		fprintf(stderr,
+			"warning: failed to do hugetlb mmap (%p, %zu): %d\n",
+			req, size, errno);
+		hugetlb_disabled = 1;
+		flags &= ~MAP_HUGETLB;
+		ret = mmap(req, size, prot, flags, -1, 0);
+	}
 	if (ret == MAP_FAILED)
 		return NULL;
-	if (ret != req)
-		printf("warning: mmaped to %p, requested %p\n", ret, req);
+
+	if (req != NULL && ret != req)
+		fprintf(stderr,
+			"warning: mmaped to %p, requested %p\n", ret, req);
 
 	return ret;
 }
@@ -155,7 +183,18 @@ void *plat_mremap(void *ptr, size_t oldsize, size_t newsize)
 
 void plat_munmap(void *ptr, size_t size)
 {
-	munmap(ptr, size);
+	int ret;
+
+	ret = munmap(ptr, size);
+	if (ret != 0 && (size & (HUGETLB_PAGESIZE - 1))) {
+		// prehaps an autorounded hugetlb mapping?
+		size = (size + HUGETLB_PAGESIZE - 1) & ~(HUGETLB_PAGESIZE - 1);
+		ret = munmap(ptr, size);
+	}
+	if (ret != 0) {
+		fprintf(stderr,
+			"munmap(%p, %zu) failed: %d\n", ptr, size, errno);
+	}
 }
 
 /* lprintf */