kernel: add portable uncached memory allocator (ucalloc) (from sources)

1 files changed, 137 insertions, 0 deletions

diff --git a/sys/src/9/port/ucalloc.c b/sys/src/9/port/ucalloc.c
new file mode 100644
index 000000000..625553fe2
--- /dev/null
+++ b/sys/src/9/port/ucalloc.c
@@ -0,0 +1,137 @@
+/*
+ * allocate uncached memory
+ */
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+
+#include <pool.h>
+
+typedef struct Private Private;
+struct Private {
+	Lock;
+	char	msg[256];
+	char*	cur;
+};
+
+static Private ucprivate;
+
+static void
+ucpoolpanic(Pool* p, char* fmt, ...)
+{
+	va_list v;
+	Private *pv;
+	char msg[sizeof pv->msg];
+
+	pv = p->private;
+	va_start(v, fmt);
+	vseprint(pv->cur, &pv->msg[sizeof pv->msg], fmt, v);
+	va_end(v);
+	memmove(msg, pv->msg, sizeof msg);
+	iunlock(pv);
+	panic("%s", msg);
+}
+
+static void
+ucpoolprint(Pool* p, char* fmt, ...)
+{
+	va_list v;
+	Private *pv;
+
+	pv = p->private;
+	va_start(v, fmt);
+	pv->cur = vseprint(pv->cur, &pv->msg[sizeof pv->msg], fmt, v);
+	va_end(v);
+}
+
+static void
+ucpoolunlock(Pool* p)
+{
+	Private *pv;
+	char msg[sizeof pv->msg];
+
+	pv = p->private;
+	if(pv->cur == pv->msg){
+		iunlock(pv);
+		return;
+	}
+
+	memmove(msg, pv->msg, sizeof msg);
+	pv->cur = pv->msg;
+	iunlock(pv);
+
+	iprint("%.*s", sizeof pv->msg, msg);
+}
+
+static void
+ucpoollock(Pool* p)
+{
+	Private *pv;
+
+	pv = p->private;
+	ilock(pv);
+	pv->pc = getcallerpc(&p);
+	pv->cur = pv->msg;
+}
+
+static void*
+ucarena(usize size)
+{
+	void *uv, *v;
+
+	assert(size == 1*MiB);
+
+	mainmem->maxsize += 1*MiB;
+	if((v = mallocalign(1*MiB, 1*MiB, 0, 0)) == nil ||
+	    (uv = mmuuncache(v, 1*MiB)) == nil){
+		free(v);
+		mainmem->maxsize -= 1*MiB;
+		return nil;
+	}
+	return uv;
+}
+
+static Pool ucpool = {
+	.name		= "Uncached",
+	.maxsize	= 4*MiB,
+	.minarena	= 1*MiB-32,
+	.quantum	= 32,
+	.alloc		= ucarena,
+	.merge		= nil,
+	.flags		= /*POOL_TOLERANCE|POOL_ANTAGONISM|POOL_PARANOIA|*/0,
+
+	.lock		= ucpoollock,
+	.unlock		= ucpoolunlock,
+	.print		= ucpoolprint,
+	.panic		= ucpoolpanic,
+
+	.private	= &ucprivate,
+};
+
+void
+ucfree(void* v)
+{
+	if(v == nil)
+		return;
+	poolfree(&ucpool, v);
+}
+
+void*
+ucallocalign(usize size, int align, int span)
+{
+	void *v;
+
+	assert(size < ucpool.minarena-128);
+	v = poolallocalign(&ucpool, size, align, 0, span);
+	if(v)
+		memset(v, 0, size);
+	return v;
+}
+
+void*
+ucalloc(usize size)
+{
+	return ucallocalign(size, 32, 0);
+}