Import sources from 2011-03-30 iso image

1 files changed, 296 insertions, 0 deletions

diff --git a/sys/src/cmd/cwfs/mworm.c b/sys/src/cmd/cwfs/mworm.c
new file mode 100755
index 000000000..407ad6a09
--- /dev/null
+++ b/sys/src/cmd/cwfs/mworm.c
@@ -0,0 +1,296 @@
+#include	"all.h"
+
+/*
+ * multiple cat devices
+ */
+void
+mcatinit(Device *d)
+{
+	Device *x, **list;
+
+	d->cat.ndev = 0;
+	for(x=d->cat.first; x; x=x->link) {
+		devinit(x);
+		d->cat.ndev++;
+	}
+
+	list = malloc(d->cat.ndev*sizeof(Device*));
+	d->private = list;
+	for(x=d->cat.first; x; x=x->link) {
+		*list++ = x;
+		x->size = devsize(x);
+	}
+}
+
+Devsize
+mcatsize(Device *d)
+{
+	Device *x;
+	Devsize l, m;
+
+	l = 0;
+	for(x=d->cat.first; x; x=x->link) {
+		m = x->size;
+		if(m == 0) {
+			m = devsize(x);
+			x->size = m;
+		}
+		l += m;
+	}
+	return l;
+}
+
+int
+mcatread(Device *d, Off b, void *c)
+{
+	Device *x;
+	Devsize l, m;
+
+	l = 0;
+	for(x=d->cat.first; x; x=x->link) {
+		m = x->size;
+		if(m == 0) {
+			m = devsize(x);
+			x->size = m;
+		}
+		if(b < l+m)
+			return devread(x, b-l, c);
+		l += m;
+	}
+	print("mcatread past end: %Z block %lld, %lld beyond end\n",
+		d, (Wideoff)b, (Wideoff)l);
+	return 1;
+}
+
+int
+mcatwrite(Device *d, Off b, void *c)
+{
+	Device *x;
+	Devsize l, m;
+
+	l = 0;
+	for(x=d->cat.first; x; x=x->link) {
+		m = x->size;
+		if(m == 0) {
+			m = devsize(x);
+			x->size = m;
+		}
+		if(b < l+m)
+			return devwrite(x, b-l, c);
+		l += m;
+	}
+	print("mcatwrite past end: %Z block %lld, %lld beyond end\n",
+		d, (Wideoff)b, (Wideoff)l);
+	return 1;
+}
+
+/*
+ * multiple interleave devices
+ */
+void
+mlevinit(Device *d)
+{
+	Device *x;
+
+	mcatinit(d);
+	for(x=d->cat.first; x; x=x->link)
+		x->size = devsize(x);
+}
+
+Devsize
+mlevsize(Device *d)
+{
+	Device *x;
+	int n;
+	Devsize m, min;
+
+	min = 0;
+	n = 0;
+	for(x=d->cat.first; x; x=x->link) {
+		m = x->size;
+		if(m == 0) {
+			m = devsize(x);
+			x->size = m;
+		}
+		if(min == 0 || m < min)
+			min = m;
+		n++;
+	}
+	return n * min;
+}
+
+int
+mlevread(Device *d, Off b, void *c)
+{
+	int n;
+	Device **list;
+
+	n = d->cat.ndev;
+	list = d->private;
+	return devread(list[b%n], b/n, c);
+}
+
+int
+mlevwrite(Device *d, Off b, void *c)
+{
+	int n;
+	Device **list;
+
+	n = d->cat.ndev;
+	list = d->private;
+	return devwrite(list[b%n], b/n, c);
+}
+
+/*
+ * partition device
+ */
+void
+partinit(Device *d)
+{
+
+	devinit(d->part.d);
+	d->part.d->size = devsize(d->part.d);
+}
+
+Devsize
+partsize(Device *d)
+{
+	Devsize size, l;
+
+	l = d->part.d->size / 100;
+	size = d->part.size * l;
+	if(size == 0)
+		size = l*100;
+	return size;
+}
+
+int
+partread(Device *d, Off b, void *c)
+{
+	Devsize base, size, l;
+
+	l = d->part.d->size / 100;
+	base = d->part.base * l;
+	size = d->part.size * l;
+	if(size == 0)
+		size = l*100;
+	if(b < size)
+		return devread(d->part.d, base+b, c);
+	print("partread past end: %Z blk %lld size %lld\n",
+		d, (Wideoff)b, (Wideoff)size);
+	return 1;
+}
+
+int
+partwrite(Device *d, Off b, void *c)
+{
+	Devsize base, size, l;
+
+	l = d->part.d->size / 100;
+	base = d->part.base * l;
+	size = d->part.size * l;
+	if(size == 0)
+		size = l*100;
+	if(b < size)
+		return devwrite(d->part.d, base+b, c);
+	print("partwrite past end: %Z blk %lld size %lld\n",
+		d, (Wideoff)b, (Wideoff)size);
+	return 1;
+}
+
+/*
+ * mirror device
+ */
+void
+mirrinit(Device *d)
+{
+	Device *x;
+
+	mcatinit(d);
+	for(x=d->cat.first; x; x=x->link)
+		x->size = devsize(x);
+}
+
+Devsize
+mirrsize(Device *d)
+{
+	Device *x;
+	int n;
+	Devsize m, min;
+
+	min = 0;
+	n = 0;
+	for(x=d->cat.first; x; x=x->link) {
+		m = x->size;
+		if(m == 0) {
+			m = devsize(x);
+			x->size = m;
+		}
+		if(min == 0 || m < min)
+			min = m;
+		n++;
+	}
+	return min;
+}
+
+int
+mirrread(Device *d, Off b, void *c)
+{
+	Device *x;
+
+	if (d->cat.first == nil) {
+		print("mirrread: empty mirror %Z\n", d);
+		return 1;
+	}
+	for(x=d->cat.first; x; x=x->link) {
+		if(x->size == 0)
+			x->size = devsize(x);
+		if (devread(x, b, c) == 0)	/* okay? */
+			return 0;
+	}
+	// DANGER WILL ROBINSON
+	print("mirrread: all mirrors of %Z block %lld are bad\n",
+		d, (Wideoff)b);
+	return 1;
+}
+
+/*
+ * write the mirror(s) first so that a power outage, for example, will
+ * find the main device written only if the mirrors are too, thus
+ * checking the main device will also correctly check the mirror(s).
+ *
+ * devread and devwrite are synchronous; all buffering must be
+ * implemented at higher levels.
+ */
+static int
+ewrite(Device *x, Off b, void *c)
+{
+	if(x->size == 0)
+		x->size = devsize(x);
+	if (devwrite(x, b, c) != 0) {
+		print("mirrwrite: error at %Z block %lld\n", x, (Wideoff)b);
+		return 1;
+	}
+	return 0;
+}
+
+static int
+wrmirrs1st(Device *x, Off b, void *c)	// write any mirrors of x, then x
+{
+	int e;
+
+	if (x == nil)
+		return 0;
+	e = wrmirrs1st(x->link, b, c);
+	return e | ewrite(x, b, c);
+}
+
+int
+mirrwrite(Device *d, Off b, void *c)
+{
+	if (d->cat.first == nil) {
+		print("mirrwrite: empty mirror %Z\n", d);
+		return 1;
+	}
+	return wrmirrs1st(d->cat.first, b, c);
+}