diff --git a/src/libdisk/disk.c b/src/libdisk/disk.c
new file mode 100644
index 0000000..bb34b65
--- /dev/null
+++ b/src/libdisk/disk.c
@@ -0,0 +1,350 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <ctype.h>
+#include <disk.h>
+
+static Disk*
+mkwidth(Disk *disk)
+{
+	char buf[40];
+
+	sprint(buf, "%lld", disk->size);
+	disk->width = strlen(buf);
+	return disk;
+}
+
+/*
+ * Discover the disk geometry by various sleazeful means.
+ * 
+ * First, if there is a partition table in sector 0,
+ * see if all the partitions have the same end head
+ * and sector; if so, we'll assume that that's the 
+ * right count.
+ * 
+ * If that fails, we'll try looking at the geometry that the ATA
+ * driver supplied, if any, and translate that as a
+ * BIOS might. 
+ * 
+ * If that too fails, which should only happen on a SCSI
+ * disk with no currently defined partitions, we'll try
+ * various common (h, s) pairs used by BIOSes when faking
+ * the geometries.
+ */
+typedef struct Table  Table;
+typedef struct Tentry Tentry;
+struct Tentry {
+	uchar	active;			/* active flag */
+	uchar	starth;			/* starting head */
+	uchar	starts;			/* starting sector */
+	uchar	startc;			/* starting cylinder */
+	uchar	type;			/* partition type */
+	uchar	endh;			/* ending head */
+	uchar	ends;			/* ending sector */
+	uchar	endc;			/* ending cylinder */
+	uchar	xlba[4];			/* starting LBA from beginning of disc */
+	uchar	xsize[4];		/* size in sectors */
+};
+enum {
+	Toffset		= 446,		/* offset of partition table in sector */
+	Magic0		= 0x55,
+	Magic1		= 0xAA,
+	NTentry		= 4,
+};
+struct Table {
+	Tentry	entry[NTentry];
+	uchar	magic[2];
+};
+static int
+partitiongeometry(Disk *disk)
+{
+	char *rawname;
+	int i, h, rawfd, s;
+	uchar buf[512];
+	Table *t;
+
+	t = (Table*)(buf + Toffset);
+
+	/*
+	 * look for an MBR first in the /dev/sdXX/data partition, otherwise
+	 * attempt to fall back on the current partition.
+	 */
+	rawname = malloc(strlen(disk->prefix) + 5);	/* prefix + "data" + nul */
+	if(rawname == nil)
+		return -1;
+
+	strcpy(rawname, disk->prefix);
+	strcat(rawname, "data");
+	rawfd = open(rawname, OREAD);
+	free(rawname);
+	if(rawfd >= 0
+	&& seek(rawfd, 0, 0) >= 0
+	&& readn(rawfd, buf, 512) == 512
+	&& t->magic[0] == Magic0
+	&& t->magic[1] == Magic1) {
+		close(rawfd);
+	} else {
+		if(rawfd >= 0)
+			close(rawfd);
+		if(seek(disk->fd, 0, 0) < 0
+		|| readn(disk->fd, buf, 512) != 512
+		|| t->magic[0] != Magic0
+		|| t->magic[1] != Magic1) {
+			return -1;
+		}
+	}
+
+	h = s = -1;
+	for(i=0; i<NTentry; i++) {
+		if(t->entry[i].type == 0)
+			continue;
+
+		t->entry[i].ends &= 63;
+		if(h == -1) {
+			h = t->entry[i].endh;
+			s = t->entry[i].ends;
+		} else {
+			/*
+			 * Only accept the partition info if every
+			 * partition is consistent.
+			 */
+			if(h != t->entry[i].endh || s != t->entry[i].ends)
+				return -1;
+		}
+	}
+
+	if(h == -1)
+		return -1;
+
+	disk->h = h+1;	/* heads count from 0 */
+	disk->s = s;	/* sectors count from 1 */
+	disk->c = disk->secs / (disk->h*disk->s);
+	disk->chssrc = Gpart;
+	return 0;
+}
+
+/*
+ * If there is ATA geometry, use it, perhaps massaged.
+ */
+static int
+drivergeometry(Disk *disk)
+{
+	int m;
+
+	if(disk->c == 0 || disk->h == 0 || disk->s == 0)
+		return -1;
+
+	disk->chssrc = Gdisk;
+	if(disk->c < 1024)
+		return 0;
+
+	switch(disk->h) {
+	case 15:
+		disk->h = 255;
+		disk->c /= 17;
+		return 0;
+
+	default:
+		for(m = 2; m*disk->h < 256; m *= 2) {
+			if(disk->c/m < 1024) {
+				disk->c /= m;
+				disk->h *= m;
+				return 0;
+			}
+		}
+
+		/* set to 255, 63 and be done with it */
+		disk->h = 255;
+		disk->s = 63;
+		disk->c = disk->secs / (disk->h * disk->s);
+		return 0;
+	}
+	return -1;	/* not reached */
+}
+
+/*
+ * There's no ATA geometry and no partitions.
+ * Our guess is as good as anyone's.
+ */
+static struct {
+	int h;
+	int s;
+} guess[] = {
+	64, 32,
+	64, 63,
+	128, 63,
+	255, 63,
+};
+static int
+guessgeometry(Disk *disk)
+{
+	int i;
+	long c;
+
+	disk->chssrc = Gguess;
+	c = 1024;
+	for(i=0; i<nelem(guess); i++)
+		if(c*guess[i].h*guess[i].s >= disk->secs) {
+			disk->h = guess[i].h;
+			disk->s = guess[i].s;
+			disk->c = disk->secs / (disk->h * disk->s);
+			return 0;
+		}
+
+	/* use maximum values */
+	disk->h = 255;
+	disk->s = 63;
+	disk->c = disk->secs / (disk->h * disk->s);
+	return 0;
+}
+
+static void
+findgeometry(Disk *disk)
+{
+	if(partitiongeometry(disk) < 0
+	&& drivergeometry(disk) < 0
+	&& guessgeometry(disk) < 0) {	/* can't happen */
+		print("we're completely confused about your disk; sorry\n");
+		assert(0);
+	}
+}
+
+static Disk*
+openfile(Disk *disk)
+{
+	Dir *d;
+
+	if((d = dirfstat(disk->fd)) == nil){
+		free(disk);
+		return nil;
+	}
+
+	disk->secsize = 512;
+	disk->size = d->length;
+	disk->secs = disk->size / disk->secsize;
+	disk->offset = 0;
+	free(d);
+
+	findgeometry(disk);
+	return mkwidth(disk);
+}
+
+static Disk*
+opensd(Disk *disk)
+{
+	Biobuf b;
+	char *p, *f[10];
+	int nf;
+
+	Binit(&b, disk->ctlfd, OREAD);
+	while(p = Brdline(&b, '\n')) {
+		p[Blinelen(&b)-1] = '\0';
+		nf = tokenize(p, f, nelem(f));
+		if(nf >= 3 && strcmp(f[0], "geometry") == 0) {
+			disk->secsize = strtoll(f[2], 0, 0);
+			if(nf >= 6) {
+				disk->c = strtol(f[3], 0, 0);
+				disk->h = strtol(f[4], 0, 0);
+				disk->s = strtol(f[5], 0, 0);
+			}
+		}
+		if(nf >= 4 && strcmp(f[0], "part") == 0 && strcmp(f[1], disk->part) == 0) {
+			disk->offset = strtoll(f[2], 0, 0);
+			disk->secs = strtoll(f[3], 0, 0) - disk->offset;
+		}
+	}
+
+	
+	disk->size = disk->secs * disk->secsize;
+	if(disk->size <= 0) {
+		strcpy(disk->part, "");
+		disk->type = Tfile;
+		return openfile(disk);
+	}
+
+	findgeometry(disk);
+	return mkwidth(disk);
+}
+
+Disk*
+opendisk(char *disk, int rdonly, int noctl)
+{
+	char *p, *q;
+	Disk *d;
+
+	d = malloc(sizeof(*d));
+	if(d == nil)
+		return nil;
+
+	d->fd = d->wfd = d->ctlfd = -1;
+	d->rdonly = rdonly;
+
+	d->fd = open(disk, OREAD);
+	if(d->fd < 0) {
+		werrstr("cannot open disk file");
+		free(d);
+		return nil;
+	}
+
+	if(rdonly == 0) {
+		d->wfd = open(disk, OWRITE);
+		if(d->wfd < 0)
+			d->rdonly = 1;
+	}
+
+	if(noctl)
+		return openfile(d);
+
+	p = malloc(strlen(disk) + 4);	/* 4: slop for "ctl\0" */
+	if(p == nil) {
+		close(d->wfd);
+		close(d->fd);
+		free(d);
+		return nil;
+	}
+	strcpy(p, disk);
+
+	/* check for floppy(3) disk */
+	if(strlen(p) >= 7) {
+		q = p+strlen(p)-7;
+		if(q[0] == 'f' && q[1] == 'd' && isdigit(q[2]) && strcmp(q+3, "disk") == 0) {
+			strcpy(q+3, "ctl");
+			if((d->ctlfd = open(p, ORDWR)) >= 0) {
+				*q = '\0';
+				d->prefix = p;
+				d->type = Tfloppy;
+				return openfile(d);
+			}
+		}
+	}
+
+	/* attempt to find sd(3) disk or partition */
+	if(q = strrchr(p, '/'))
+		q++;
+	else
+		q = p;
+
+	strcpy(q, "ctl");
+	if((d->ctlfd = open(p, ORDWR)) >= 0) {
+		*q = '\0';
+		d->prefix = p;
+		d->type = Tsd;
+		d->part = strdup(disk+(q-p));
+		if(d->part == nil){
+			close(d->ctlfd);
+			close(d->wfd);
+			close(d->fd);
+			free(p);
+			free(d);
+			return nil;
+		}
+		return opensd(d);
+	}
+
+	*q = '\0';
+	d->prefix = p;
+	/* assume we just have a normal file */
+	d->type = Tfile;
+	return openfile(d);
+}
+
diff --git a/src/libdisk/mkfile b/src/libdisk/mkfile
new file mode 100644
index 0000000..af49af6
--- /dev/null
+++ b/src/libdisk/mkfile
@@ -0,0 +1,19 @@
+<$PLAN9/src/mkhdr
+
+OFILES=\
+	disk.$O\
+	proto.$O\
+	scsi.$O\
+
+HFILES=$PLAN9/include/disk.h
+LIB=libdisk.a
+
+UPDATE=\
+	mkfile\
+	$HFILES\
+	${OFILES:%.$O=%.c}\
+
+<$PLAN9/src/mksyslib
+
+$O.test: test.$O $LIB
+	$LD -o $target test.$O $LIB
diff --git a/src/libdisk/proto.c b/src/libdisk/proto.c
new file mode 100644
index 0000000..8c94ddc
--- /dev/null
+++ b/src/libdisk/proto.c
@@ -0,0 +1,513 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <auth.h>
+#include <fcall.h>
+#include <disk.h>
+
+enum {
+	LEN	= 8*1024,
+	HUNKS	= 128,
+};
+
+#undef warn
+#define warn protowarn
+
+#undef getmode 
+#define getmode protogetmode
+
+typedef struct File File;
+struct File{
+	char	*new;
+	char	*elem;
+	char	*old;
+	char	*uid;
+	char	*gid;
+	ulong	mode;
+};
+
+typedef void Mkfserr(char*, void*);
+typedef void Mkfsenum(char*, char*, Dir*, void*);
+
+typedef struct Name Name;
+struct Name {
+	int n;
+	char *s;
+};
+
+typedef struct Mkaux Mkaux;
+struct Mkaux {
+	Mkfserr *warn;
+	Mkfsenum *mkenum;
+	char *root;
+	char *proto;
+	jmp_buf jmp;
+	Biobuf *b;
+
+	Name oldfile;
+	Name fullname;
+	int	lineno;
+	int	indent;
+
+	void *a;
+};
+
+static void domkfs(Mkaux *mkaux, File *me, int level);
+
+static int	copyfile(Mkaux*, File*, Dir*, int);
+static void	freefile(File*);
+static File*	getfile(Mkaux*, File*);
+static char*	getmode(Mkaux*, char*, ulong*);
+static char*	getname(Mkaux*, char*, char**);
+static char*	getpath(Mkaux*, char*);
+static int	mkfile(Mkaux*, File*);
+static char*	mkpath(Mkaux*, char*, char*);
+static void	mktree(Mkaux*, File*, int);
+static void	setnames(Mkaux*, File*);
+static void	skipdir(Mkaux*);
+static void	warn(Mkaux*, char *, ...);
+
+//static void
+//mprint(char *new, char *old, Dir *d, void*)
+//{
+//	print("%s %s %D\n", new, old, d);
+//}
+
+int
+rdproto(char *proto, char *root, Mkfsenum *mkenum, Mkfserr *mkerr, void *a)
+{
+	Mkaux mx, *m;
+	File file;
+	int rv;
+
+	m = &mx;
+	memset(&mx, 0, sizeof mx);
+	if(root == nil)
+		root = "/";
+
+	m->root = root;
+	m->warn = mkerr;
+	m->mkenum = mkenum;
+	m->a = a;
+	m->proto = proto;
+	m->lineno = 0;
+	m->indent = 0;
+	if((m->b = Bopen(proto, OREAD)) == nil) {
+		werrstr("open '%s': %r", proto);
+		return -1;
+	}
+
+	memset(&file, 0, sizeof file);
+	file.new = "";
+	file.old = nil;
+
+	*(&rv) = 0;
+	if(setjmp(m->jmp) == 0)
+		domkfs(m, &file, -1);
+	else
+		rv = -1;
+	free(m->oldfile.s);
+	free(m->fullname.s);
+	return rv;
+}
+
+static void*
+emalloc(Mkaux *mkaux, ulong n)
+{
+	void *v;
+
+	v = malloc(n);
+	if(v == nil)
+		longjmp(mkaux->jmp, 1);	/* memory leak */
+	memset(v, 0, n);
+	return v;
+}
+
+static char*
+estrdup(Mkaux *mkaux, char *s)
+{
+	s = strdup(s);
+	if(s == nil)
+		longjmp(mkaux->jmp, 1);	/* memory leak */
+	return s;
+}
+
+static void
+domkfs(Mkaux *mkaux, File *me, int level)
+{
+	File *child;
+	int rec;
+
+	child = getfile(mkaux, me);
+	if(!child)
+		return;
+	if((child->elem[0] == '+' || child->elem[0] == '*') && child->elem[1] == '\0'){
+		rec = child->elem[0] == '+';
+		free(child->new);
+		child->new = estrdup(mkaux, me->new);
+		setnames(mkaux, child);
+		mktree(mkaux, child, rec);
+		freefile(child);
+		child = getfile(mkaux, me);
+	}
+	while(child && mkaux->indent > level){
+		if(mkfile(mkaux, child))
+			domkfs(mkaux, child, mkaux->indent);
+		freefile(child);
+		child = getfile(mkaux, me);
+	}
+	if(child){
+		freefile(child);
+		Bseek(mkaux->b, -Blinelen(mkaux->b), 1);
+		mkaux->lineno--;
+	}
+}
+
+static void
+mktree(Mkaux *mkaux, File *me, int rec)
+{
+	File child;
+	Dir *d;
+	int i, n, fd;
+
+	fd = open(mkaux->oldfile.s, OREAD);
+	if(fd < 0){
+		warn(mkaux, "can't open %s: %r", mkaux->oldfile.s);
+		return;
+	}
+
+	child = *me;
+	while((n = dirread(fd, &d)) > 0){
+		for(i = 0; i < n; i++){
+			child.new = mkpath(mkaux, me->new, d[i].name);
+			if(me->old)
+				child.old = mkpath(mkaux, me->old, d[i].name);
+			child.elem = d[i].name;
+			setnames(mkaux, &child);
+			if((!(d[i].mode&DMDIR) || rec) && copyfile(mkaux, &child, &d[i], 1) && rec)
+				mktree(mkaux, &child, rec);
+			free(child.new);
+			if(child.old)
+				free(child.old);
+		}
+	}
+	close(fd);
+}
+
+static int
+mkfile(Mkaux *mkaux, File *f)
+{
+	Dir *d;
+
+	if((d = dirstat(mkaux->oldfile.s)) == nil){
+		warn(mkaux, "can't stat file %s: %r", mkaux->oldfile.s);
+		skipdir(mkaux);
+		return 0;
+	}
+	return copyfile(mkaux, f, d, 0);
+}
+
+enum {
+	SLOP = 30
+};
+
+static void
+setname(Mkaux *mkaux, Name *name, char *s1, char *s2)
+{
+	int l;
+
+	l = strlen(s1)+strlen(s2)+1;
+	if(name->n < l+SLOP/2) {
+		free(name->s);
+		name->s = emalloc(mkaux, l+SLOP);
+		name->n = l+SLOP;
+	}
+	snprint(name->s, name->n, "%s%s%s", s1, s1[0]==0 || s1[strlen(s1)-1]!='/' ? "/" : "", s2);
+}
+
+static int
+copyfile(Mkaux *mkaux, File *f, Dir *d, int permonly)
+{
+	Dir *nd;
+	ulong xmode;
+	char *p;
+
+	setname(mkaux, &mkaux->fullname, mkaux->root, f->old ? f->old : f->new);
+	/*
+	 * Extra stat here is inefficient but accounts for binds.
+	 */
+	if((nd = dirstat(mkaux->fullname.s)) != nil)
+		d = nd;
+
+	d->name = f->elem;
+	if(d->type != 'M'){
+		d->uid = "sys";
+		d->gid = "sys";
+		xmode = (d->mode >> 6) & 7;
+		d->mode |= xmode | (xmode << 3);
+	}
+	if(strcmp(f->uid, "-") != 0)
+		d->uid = f->uid;
+	if(strcmp(f->gid, "-") != 0)
+		d->gid = f->gid;
+	if(f->mode != ~0){
+		if(permonly)
+			d->mode = (d->mode & ~0666) | (f->mode & 0666);
+		else if((d->mode&DMDIR) != (f->mode&DMDIR))
+			warn(mkaux, "inconsistent mode for %s", f->new);
+		else
+			d->mode = f->mode;
+	}
+
+	if(p = strrchr(f->new, '/'))
+		d->name = p+1;
+	else
+		d->name = f->new;
+
+	mkaux->mkenum(f->new, mkaux->fullname.s, d, mkaux->a);
+	xmode = d->mode;
+	free(nd);
+	return (xmode&DMDIR) != 0;
+}
+
+static char *
+mkpath(Mkaux *mkaux, char *prefix, char *elem)
+{
+	char *p;
+	int n;
+
+	n = strlen(prefix) + strlen(elem) + 2;
+	p = emalloc(mkaux, n);
+	strcpy(p, prefix);
+	strcat(p, "/");
+	strcat(p, elem);
+	return p;
+}
+
+static void
+setnames(Mkaux *mkaux, File *f)
+{
+	
+	if(f->old){
+		if(f->old[0] == '/')
+			setname(mkaux, &mkaux->oldfile, f->old, "");
+		else
+			setname(mkaux, &mkaux->oldfile, mkaux->root, f->old);
+	} else
+		setname(mkaux, &mkaux->oldfile, mkaux->root, f->new);
+}
+
+static void
+freefile(File *f)
+{
+	if(f->old)
+		free(f->old);
+	if(f->new)
+		free(f->new);
+	free(f);
+}
+
+/*
+ * skip all files in the proto that
+ * could be in the current dir
+ */
+static void
+skipdir(Mkaux *mkaux)
+{
+	char *p, c;
+	int level;
+
+	if(mkaux->indent < 0)
+		return;
+	level = mkaux->indent;
+	for(;;){
+		mkaux->indent = 0;
+		p = Brdline(mkaux->b, '\n');
+		mkaux->lineno++;
+		if(!p){
+			mkaux->indent = -1;
+			return;
+		}
+		while((c = *p++) != '\n')
+			if(c == ' ')
+				mkaux->indent++;
+			else if(c == '\t')
+				mkaux->indent += 8;
+			else
+				break;
+		if(mkaux->indent <= level){
+			Bseek(mkaux->b, -Blinelen(mkaux->b), 1);
+			mkaux->lineno--;
+			return;
+		}
+	}
+}
+
+static File*
+getfile(Mkaux *mkaux, File *old)
+{
+	File *f;
+	char *elem;
+	char *p;
+	int c;
+
+	if(mkaux->indent < 0)
+		return 0;
+loop:
+	mkaux->indent = 0;
+	p = Brdline(mkaux->b, '\n');
+	mkaux->lineno++;
+	if(!p){
+		mkaux->indent = -1;
+		return 0;
+	}
+	while((c = *p++) != '\n')
+		if(c == ' ')
+			mkaux->indent++;
+		else if(c == '\t')
+			mkaux->indent += 8;
+		else
+			break;
+	if(c == '\n' || c == '#')
+		goto loop;
+	p--;
+	f = emalloc(mkaux, sizeof *f);
+	p = getname(mkaux, p, &elem);
+	if(p == nil)
+		return nil;
+
+	f->new = mkpath(mkaux, old->new, elem);
+	free(elem);
+	f->elem = utfrrune(f->new, L'/') + 1;
+	p = getmode(mkaux, p, &f->mode);
+	p = getname(mkaux, p, &f->uid);	/* LEAK */
+	if(p == nil)
+		return nil;
+
+	if(!*f->uid)
+		strcpy(f->uid, "-");
+	p = getname(mkaux, p, &f->gid);	/* LEAK */
+	if(p == nil)
+		return nil;
+
+	if(!*f->gid)
+		strcpy(f->gid, "-");
+	f->old = getpath(mkaux, p);
+	if(f->old && strcmp(f->old, "-") == 0){
+		free(f->old);
+		f->old = 0;
+	}
+	setnames(mkaux, f);
+
+	return f;
+}
+
+static char*
+getpath(Mkaux *mkaux, char *p)
+{
+	char *q, *new;
+	int c, n;
+
+	while((c = *p) == ' ' || c == '\t')
+		p++;
+	q = p;
+	while((c = *q) != '\n' && c != ' ' && c != '\t')
+		q++;
+	if(q == p)
+		return 0;
+	n = q - p;
+	new = emalloc(mkaux, n + 1);
+	memcpy(new, p, n);
+	new[n] = 0;
+	return new;
+}
+
+static char*
+getname(Mkaux *mkaux, char *p, char **buf)
+{
+	char *s, *start;
+	int c;
+
+	while((c = *p) == ' ' || c == '\t')
+		p++;
+
+	start = p;
+	while((c = *p) != '\n' && c != ' ' && c != '\t')
+		p++;
+
+	*buf = malloc(p+2-start);	/* +2: need at least 2 bytes; might strcpy "-" into buf */
+	if(*buf == nil)
+		return nil;
+	memmove(*buf, start, p-start);
+
+	(*buf)[p-start] = '\0';
+
+	if(**buf == '$'){
+		s = getenv(*buf+1);
+		if(s == 0){
+			warn(mkaux, "can't read environment variable %s", *buf+1);
+			skipdir(mkaux);
+			free(*buf);
+			return nil;
+		}
+		free(*buf);
+		*buf = s;
+	}
+	return p;
+}
+
+static char*
+getmode(Mkaux *mkaux, char *p, ulong *xmode)
+{
+	char *buf, *s;
+	ulong m;
+
+	*xmode = ~0;
+	p = getname(mkaux, p, &buf);
+	if(p == nil)
+		return nil;
+
+	s = buf;
+	if(!*s || strcmp(s, "-") == 0)
+		return p;
+	m = 0;
+	if(*s == 'd'){
+		m |= DMDIR;
+		s++;
+	}
+	if(*s == 'a'){
+		m |= DMAPPEND;
+		s++;
+	}
+	if(*s == 'l'){
+		m |= DMEXCL;
+		s++;
+	}
+	if(s[0] < '0' || s[0] > '7'
+	|| s[1] < '0' || s[1] > '7'
+	|| s[2] < '0' || s[2] > '7'
+	|| s[3]){
+		warn(mkaux, "bad mode specification %s", buf);
+		free(buf);
+		return p;
+	}
+	*xmode = m | strtoul(s, 0, 8);
+	free(buf);
+	return p;
+}
+
+static void
+warn(Mkaux *mkaux, char *fmt, ...)
+{
+	char buf[256];
+	va_list va;
+
+	va_start(va, fmt);
+	vseprint(buf, buf+sizeof(buf), fmt, va);
+	va_end(va);
+
+	if(mkaux->warn)
+		mkaux->warn(buf, mkaux->a);
+	else
+		fprint(2, "warning: %s\n", buf);
+}
diff --git a/src/libdisk/scsi.c b/src/libdisk/scsi.c
new file mode 100644
index 0000000..ccab244
--- /dev/null
+++ b/src/libdisk/scsi.c
@@ -0,0 +1,327 @@
+/*
+ * Now thread-safe.
+ *
+ * The codeqlock guarantees that once codes != nil, that pointer will never 
+ * change nor become invalid.
+ *
+ * The QLock in the Scsi structure moderates access to the raw device.
+ * We should probably export some of the already-locked routines, but
+ * there hasn't been a need.
+ */
+
+#include <u.h>
+#include <libc.h>
+#include <disk.h>
+
+int scsiverbose;
+
+#define codefile "/sys/lib/scsicodes"
+
+static char *codes;
+static QLock codeqlock;
+
+static void
+getcodes(void)
+{
+	Dir *d;
+	int n, fd;
+
+	if(codes != nil)
+		return;
+
+	qlock(&codeqlock);
+	if(codes != nil) {
+		qunlock(&codeqlock);
+		return;
+	}
+
+	if((d = dirstat(codefile)) == nil || (fd = open(codefile, OREAD)) < 0) {
+		qunlock(&codeqlock);
+		return;
+	}
+
+	codes = malloc(1+d->length+1);
+	if(codes == nil) {
+		close(fd);
+		qunlock(&codeqlock);
+		free(d);
+		return;
+	}
+
+	codes[0] = '\n';	/* for searches */
+	n = readn(fd, codes+1, d->length);
+	close(fd);
+	free(d);
+
+	if(n < 0) {
+		free(codes);
+		codes = nil;
+		qunlock(&codeqlock);
+		return;
+	}
+	codes[n] = '\0';
+	qunlock(&codeqlock);
+}
+	
+char*
+scsierror(int asc, int ascq)
+{
+	char *p, *q;
+	static char search[32];
+	static char buf[128];
+
+	getcodes();
+
+	if(codes) {
+		sprint(search, "\n%.2ux%.2ux ", asc, ascq);
+		if(p = strstr(codes, search)) {
+			p += 6;
+			if((q = strchr(p, '\n')) == nil)
+				q = p+strlen(p);
+			snprint(buf, sizeof buf, "%.*s", (int)(q-p), p);
+			return buf;
+		}
+
+		sprint(search, "\n%.2ux00", asc);
+		if(p = strstr(codes, search)) {
+			p += 6;
+			if((q = strchr(p, '\n')) == nil)
+				q = p+strlen(p);
+			snprint(buf, sizeof buf, "(ascq #%.2ux) %.*s", ascq, (int)(q-p), p);
+			return buf;
+		}
+	}
+
+	sprint(buf, "scsi #%.2ux %.2ux", asc, ascq);
+	return buf;
+}
+
+
+static int
+_scsicmd(Scsi *s, uchar *cmd, int ccount, void *data, int dcount, int io, int dolock)
+{
+	uchar resp[16];
+	int n;
+	long status;
+
+	if(dolock)
+		qlock(&s->lk);
+	if(write(s->rawfd, cmd, ccount) != ccount) {
+		werrstr("cmd write: %r");
+		if(dolock)
+			qunlock(&s->lk);
+		return -1;
+	}
+
+	switch(io){
+	case Sread:
+		n = read(s->rawfd, data, dcount);
+		if(n < 0 && scsiverbose)
+			fprint(2, "dat read: %r: cmd 0x%2.2uX\n", cmd[0]);
+		break;
+	case Swrite:
+		n = write(s->rawfd, data, dcount);
+		if(n != dcount && scsiverbose)
+			fprint(2, "dat write: %r: cmd 0x%2.2uX\n", cmd[0]);
+		break;
+	default:
+	case Snone:
+		n = write(s->rawfd, resp, 0);
+		if(n != 0 && scsiverbose)
+			fprint(2, "none write: %r: cmd 0x%2.2uX\n", cmd[0]);
+		break;
+	}
+
+	memset(resp, 0, sizeof(resp));
+	if(read(s->rawfd, resp, sizeof(resp)) < 0) {
+		werrstr("resp read: %r\n");
+		if(dolock)
+			qunlock(&s->lk);
+		return -1;
+	}
+	if(dolock)
+		qunlock(&s->lk);
+
+	resp[sizeof(resp)-1] = '\0';
+	status = atoi((char*)resp);
+	if(status == 0)
+		return n;
+
+	werrstr("cmd %2.2uX: status %luX dcount %d n %d", cmd[0], status, dcount, n);
+	return -1;
+}
+
+int
+scsicmd(Scsi *s, uchar *cmd, int ccount, void *data, int dcount, int io)
+{
+	return _scsicmd(s, cmd, ccount, data, dcount, io, 1);
+}
+
+static int
+_scsiready(Scsi *s, int dolock)
+{
+	uchar cmd[6], resp[16];
+	int status, i;
+
+	if(dolock)
+		qlock(&s->lk);
+	for(i=0; i<3; i++) {
+		memset(cmd, 0, sizeof(cmd));
+		cmd[0] = 0x00;	/* unit ready */
+		if(write(s->rawfd, cmd, sizeof(cmd)) != sizeof(cmd)) {
+			if(scsiverbose)
+				fprint(2, "ur cmd write: %r\n");
+			goto bad;
+		}
+		write(s->rawfd, resp, 0);
+		if(read(s->rawfd, resp, sizeof(resp)) < 0) {
+			if(scsiverbose)
+				fprint(2, "ur resp read: %r\n");
+			goto bad;
+		}
+		resp[sizeof(resp)-1] = '\0';
+		status = atoi((char*)resp);
+		if(status == 0 || status == 0x02) {
+			if(dolock)
+				qunlock(&s->lk);
+			return 0;
+		}
+		if(scsiverbose)
+			fprint(2, "target: bad status: %x\n", status);
+	bad:;
+	}
+	if(dolock)
+		qunlock(&s->lk);
+	return -1;
+}
+
+int
+scsiready(Scsi *s)
+{
+	return _scsiready(s, 1);
+}
+
+int
+scsi(Scsi *s, uchar *cmd, int ccount, void *v, int dcount, int io)
+{
+	uchar req[6], sense[255], *data;
+	int tries, code, key, n;
+	char *p;
+
+	data = v;
+	SET(key); SET(code);
+	qlock(&s->lk);
+	for(tries=0; tries<2; tries++) {
+		n = _scsicmd(s, cmd, ccount, data, dcount, io, 0);
+		if(n >= 0) {
+			qunlock(&s->lk);
+			return n;
+		}
+
+		/*
+		 * request sense
+		 */
+		memset(req, 0, sizeof(req));
+		req[0] = 0x03;
+		req[4] = sizeof(sense);
+		memset(sense, 0xFF, sizeof(sense));
+		if((n=_scsicmd(s, req, sizeof(req), sense, sizeof(sense), Sread, 0)) < 14)
+			if(scsiverbose)
+				fprint(2, "reqsense scsicmd %d: %r\n", n);
+	
+		if(_scsiready(s, 0) < 0)
+			if(scsiverbose)
+				fprint(2, "unit not ready\n");
+	
+		key = sense[2];
+		code = sense[12];
+		if(code == 0x17 || code == 0x18) {	/* recovered errors */
+			qunlock(&s->lk);
+			return dcount;
+		}
+		if(code == 0x28 && cmd[0] == 0x43) {	/* get info and media changed */
+			s->nchange++;
+			s->changetime = time(0);
+			continue;
+		}
+	}
+
+	/* drive not ready, or medium not present */
+	if(cmd[0] == 0x43 && key == 2 && (code == 0x3a || code == 0x04)) {
+		s->changetime = 0;
+		qunlock(&s->lk);
+		return -1;
+	}
+	qunlock(&s->lk);
+
+	if(cmd[0] == 0x43 && key == 5 && code == 0x24)	/* blank media */
+		return -1;
+
+	p = scsierror(code, sense[13]);
+
+	werrstr("cmd #%.2ux: %s", cmd[0], p);
+
+	if(scsiverbose)
+		fprint(2, "scsi cmd #%.2ux: %.2ux %.2ux %.2ux: %s\n", cmd[0], key, code, sense[13], p);
+
+//	if(key == 0)
+//		return dcount;
+	return -1;
+}
+
+Scsi*
+openscsi(char *dev)
+{
+	Scsi *s;
+	int rawfd, ctlfd, l, n;
+	char *name, *p, buf[512];
+
+	l = strlen(dev)+1+3+1;
+	name = malloc(l);
+	if(name == nil)
+		return nil;
+
+	snprint(name, l, "%s/raw", dev);
+	if((rawfd = open(name, ORDWR)) < 0) {
+		free(name);
+		return nil;
+	}
+
+	snprint(name, l, "%s/ctl", dev);
+	if((ctlfd = open(name, ORDWR)) < 0) {
+		free(name);
+	Error:
+		close(rawfd);
+		return nil;
+	}
+	free(name);
+
+	n = readn(ctlfd, buf, sizeof buf);
+	close(ctlfd);
+	if(n <= 0)
+		goto Error;
+
+	if(strncmp(buf, "inquiry ", 8) != 0 || (p = strchr(buf, '\n')) == nil)
+		goto Error;
+	*p = '\0';
+
+	if((p = strdup(buf+8)) == nil)
+		goto Error;
+
+	s = malloc(sizeof(*s));
+	if(s == nil) {
+	Error1:
+		free(p);
+		goto Error;
+	}
+	memset(s, 0, sizeof(*s));
+
+	s->rawfd = rawfd;
+	s->inquire = p;
+	s->changetime = time(0);
+	
+	if(scsiready(s) < 0)
+		goto Error1;
+
+	return s;
+}
diff --git a/src/libdisk/test.c b/src/libdisk/test.c
new file mode 100644
index 0000000..eed3713
--- /dev/null
+++ b/src/libdisk/test.c
@@ -0,0 +1,14 @@
+#include <u.h>
+#include <libc.h>
+#include <disk.h>
+
+char *src[] = { "part", "disk", "guess" };
+void
+main(int argc, char **argv)
+{
+	Disk *disk;
+
+	assert(argc == 2);
+	disk = opendisk(argv[1], 0, 0);
+	print("%d %d %d from %s\n", disk->c, disk->h, disk->s, src[disk->chssrc]);
+}