20060303

1 files changed, 72 insertions, 0 deletions

diff --git a/os/manga/ioring.c b/os/manga/ioring.c
new file mode 100644
index 00000000..fa3dc209
--- /dev/null
+++ b/os/manga/ioring.c
@@ -0,0 +1,72 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "io.h"
+
+/*
+ * Host Communication buffer rings
+ */
+
+/*
+ * initialise receive and transmit buffer rings
+ *
+ * the ring entries must be uncached
+ */
+
+BD*
+bdalloc(ulong nd)
+{
+	BD *b;
+
+	b = xspanalloc(nd*sizeof(*b), CACHELINESZ, 0);
+	if(b == nil)
+		panic("bdalloc");
+	return mmucacheinhib(b, nd*sizeof(*b));
+}
+
+int
+ioringinit(Ring* r, int nrdre, int ntdre)
+{
+	int i;
+
+	r->nrdre = nrdre;
+	if(r->rdr == nil)
+		r->rdr = bdalloc(nrdre);
+	if(r->rxb == nil)
+		r->rxb = malloc(nrdre*sizeof(Block*));
+	if(r->rdr == nil || r->rxb == nil)
+		return -1;
+	for(i = 0; i < nrdre; i++){
+		r->rxb[i] = nil;
+		r->rdr[i].ctrl = 0;
+		r->rdr[i].size = 0;
+		r->rdr[i].addr = 0;
+		if(i)
+			r->rdr[i-1].next = PADDR(&r->rdr[i]);
+	}
+	r->rdr[i-1].next = PADDR(&r->rdr[0]);
+	r->rdrx = 0;
+
+	r->ntdre = ntdre;
+	if(r->tdr == nil)
+		r->tdr = bdalloc(ntdre);
+	if(r->txb == nil)
+		r->txb = malloc(ntdre*sizeof(Block*));
+	if(r->tdr == nil || r->txb == nil)
+		return -1;
+	for(i = 0; i < ntdre; i++){
+		r->txb[i] = nil;
+		r->tdr[i].ctrl = 0;
+		r->tdr[i].size = 0;
+		r->tdr[i].addr = 0;
+		if(i)
+			r->tdr[i-1].next = PADDR(&r->tdr[i]);
+	}
+	r->tdr[i-1].next = PADDR(&r->tdr[0]);
+	r->tdrh = 0;
+	r->tdri = 0;
+	r->ntq = 0;
+	return 0;
+}