start mmap'ing vram, with hugetlb if possible

4 files changed, 61 insertions, 5 deletions

diff --git a/frontend/common/plat.h b/frontend/common/plat.h
index 0a9fc0b..416f8ac 100644
--- a/frontend/common/plat.h
+++ b/frontend/common/plat.h
@@ -45,6 +45,10 @@ int  plat_is_dir(const char *path);
 int  plat_wait_event(int *fds_hnds, int count, int timeout_ms);
 void plat_sleep_ms(int ms);
 
+void *plat_mmap(unsigned long addr, size_t size, int need_exec);
+void *plat_mremap(void *ptr, size_t oldsize, size_t newsize);
+void  plat_munmap(void *ptr, size_t size);
+
 /* timers, to be used for time diff and must refer to the same clock */
 unsigned int plat_get_ticks_ms(void);
 unsigned int plat_get_ticks_us(void);
diff --git a/frontend/linux/plat.c b/frontend/linux/plat.c
index b7152b5..044084e 100644
--- a/frontend/linux/plat.c
+++ b/frontend/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 +134,34 @@ 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)
 {
+	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 (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 +181,18 @@ 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 */
diff --git a/frontend/plugin_lib.c b/frontend/plugin_lib.c
index 4dbb9a7..c2e2ab4 100644
--- a/frontend/plugin_lib.c
+++ b/frontend/plugin_lib.c
@@ -21,6 +21,7 @@
 #include "linux/fbdev.h"
 #include "common/fonts.h"
 #include "common/input.h"
+#include "common/plat.h"
 #include "menu.h"
 #include "main.h"
 #include "plat.h"
@@ -484,12 +485,24 @@ static void pl_get_layer_pos(int *x, int *y, int *w, int *h)
 	*h = g_layer_h;
 }
 
+static void *pl_mmap(unsigned int size)
+{
+	return plat_mmap(0, size, 0);
+}
+
+static void pl_munmap(void *ptr, unsigned int size)
+{
+	plat_munmap(ptr, size);
+}
+
 struct rearmed_cbs pl_rearmed_cbs = {
 	pl_get_layer_pos,
 	pl_vout_open,
 	pl_vout_set_mode,
 	pl_vout_flip,
 	pl_vout_close,
+	pl_mmap,
+	pl_munmap,
 };
 
 /* watchdog */
diff --git a/frontend/plugin_lib.h b/frontend/plugin_lib.h
index 7687bf8..1701d06 100644
--- a/frontend/plugin_lib.h
+++ b/frontend/plugin_lib.h
@@ -44,6 +44,8 @@ struct rearmed_cbs {
 	void *(*pl_vout_set_mode)(int w, int h, int bpp);
 	void *(*pl_vout_flip)(void);
 	void  (*pl_vout_close)(void);
+	void *(*mmap)(unsigned int size);
+	void  (*munmap)(void *ptr, unsigned int size);
 	// these are only used by some frontends
 	void  (*pl_vout_raw_flip)(int x, int y);
 	void  (*pl_vout_set_raw_vram)(void *vram);