Add a device driver for the BIOS device for CD-ROM's booted via El Torito

no emulation mode.  Unlike other BIOS devices, this device uses 2048 byte
sectors.  Also, the bioscd driver does not have to worry about slices
or partitions.

7 files changed, 424 insertions, 21 deletions

diff --git a/sys/boot/i386/libi386/Makefile b/sys/boot/i386/libi386/Makefile
index 6bcf8dc..7026cd0 100644
--- a/sys/boot/i386/libi386/Makefile
+++ b/sys/boot/i386/libi386/Makefile
@@ -6,8 +6,8 @@ NOPROFILE=
 INTERNALLIB=		true
 INTERNALSTATICLIB=	true
 
-SRCS=	aout_freebsd.c biosacpi.c biosdisk.c biosmem.c biospnp.c biospci.c \
-	bootinfo.c comconsole.c devicename.c elf_freebsd.c gatea20.c \
+SRCS=	aout_freebsd.c biosacpi.c bioscd.c biosdisk.c biosmem.c biospnp.c \
+	biospci.c bootinfo.c comconsole.c devicename.c elf_freebsd.c gatea20.c \
 	i386_copy.c i386_module.c nullconsole.c pxe.c pxetramp.s \
 	time.c vidconsole.c
 
diff --git a/sys/boot/i386/libi386/bioscd.c b/sys/boot/i386/libi386/bioscd.c
new file mode 100644
index 0000000..5a9605e
--- /dev/null
+++ b/sys/boot/i386/libi386/bioscd.c
@@ -0,0 +1,358 @@
+/*-
+ * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
+ * Copyright (c) 2001 John H. Baldwin <jhb@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * BIOS CD device handling for CD's that have been booted off of via no
+ * emulation booting as defined in the El Torito standard.
+ * 
+ * Ideas and algorithms from:
+ *
+ * - FreeBSD libi386/biosdisk.c
+ *
+ */
+
+#include <stand.h>
+
+#include <sys/reboot.h>
+#include <machine/param.h>
+#include <machine/psl.h>
+
+#include <stdarg.h>
+
+#include <bootstrap.h>
+#include <btxv86.h>
+#include "libi386.h"
+
+#define BIOSCD_SECSIZE		2048
+#define BUFSIZE			(1 * BIOSCD_SECSIZE)
+#define	MAXBCDEV		1
+
+/* Major numbers for devices we frontend for. */
+#define ACDMAJOR		117
+#define	CDMAJOR			15
+
+#ifdef DISK_DEBUG
+# define DEBUG(fmt, args...)	printf("%s: " fmt "\n" , __FUNCTION__ , ## args)
+#else
+# define DEBUG(fmt, args...)
+#endif
+
+struct specification_packet {
+	u_char	sp_size;
+	u_char	sp_bootmedia;
+	u_char	sp_drive;
+	u_char	sp_controller;
+	u_int	sp_lba;
+	u_short	sp_devicespec;
+	u_short	sp_buffersegment;
+	u_short	sp_loadsegment;
+	u_short	sp_sectorcount;
+	u_short	sp_cylsec;
+	u_char	sp_head;
+};
+
+/*
+ * List of BIOS devices, translation from disk unit number to
+ * BIOS unit number.
+ */
+static struct bcinfo {
+	int	bc_unit;		/* BIOS unit number */
+	struct specification_packet bc_sp;
+} bcinfo [MAXBCDEV];
+static int nbcinfo = 0;
+
+static int	bc_read(int unit, daddr_t dblk, int blks, caddr_t dest);
+static int	bc_init(void);
+static int	bc_strategy(void *devdata, int flag, daddr_t dblk,
+		    size_t size, char *buf, size_t *rsize);
+static int	bc_realstrategy(void *devdata, int flag, daddr_t dblk,
+		    size_t size, char *buf, size_t *rsize);
+static int	bc_open(struct open_file *f, ...);
+static int	bc_close(struct open_file *f);
+static void	bc_print(int verbose);
+
+struct devsw bioscd = {
+	"cd", 
+	DEVT_CD, 
+	bc_init,
+	bc_strategy, 
+	bc_open, 
+	bc_close, 
+	noioctl,
+	bc_print,
+	NULL
+};
+
+/*
+ * Translate between BIOS device numbers and our private unit numbers.
+ */
+int
+bc_bios2unit(int biosdev)
+{
+	int i;
+    
+	DEBUG("looking for bios device 0x%x", biosdev);
+	for (i = 0; i < nbcinfo; i++) {
+		DEBUG("bc unit %d is BIOS device 0x%x", i, bcinfo[i].bc_unit);
+		if (bcinfo[i].bc_unit == biosdev)
+			return(i);
+	}
+	return(-1);
+}
+
+int
+bc_unit2bios(int unit)
+{
+	if ((unit >= 0) && (unit < nbcinfo))
+		return(bcinfo[unit].bc_unit);
+	return(-1);
+}
+
+/*    
+ * We can't quiz, we have to be told what device to use, so this functoin
+ * doesn't do anything.  Instead, the loader calls bc_add() with the BIOS
+ * device number to add.
+ */
+static int
+bc_init(void) 
+{
+
+	return (0);
+}
+
+int
+bc_add(int biosdev)
+{
+
+	if (nbcinfo >= MAXBCDEV)
+		return (-1);
+	bcinfo[nbcinfo].bc_unit = biosdev;
+	v86.ctl = V86_FLAGS;
+	v86.addr = 0x13;
+	v86.eax = 0x4b01;
+	v86.edx = biosdev;
+	v86.ds = VTOPSEG(&bcinfo[nbcinfo].bc_sp);
+	v86.esi = VTOPOFF(&bcinfo[nbcinfo].bc_sp);
+	v86int();
+	if ((v86.eax & 0xff00) != 0)
+		return (-1);
+
+	printf("BIOS CD is cd%d\n", nbcinfo);
+	nbcinfo++;
+	return(0);
+}
+
+/*
+ * Print information about disks
+ */
+static void
+bc_print(int verbose)
+{
+	int i;
+	char line[80];
+    
+	for (i = 0; i < nbcinfo; i++) {
+		sprintf(line, "    cd%d: Device 0x%x\n", i,
+		    bcinfo[i].bc_sp.sp_devicespec);
+		pager_output(line);
+	}
+}
+
+/*
+ * Attempt to open the disk described by (dev) for use by (f).
+ */
+static int 
+bc_open(struct open_file *f, ...)
+{
+	va_list ap;
+	struct i386_devdesc *dev;
+	int error;
+
+	va_start(ap, f);
+	dev = va_arg(ap, struct i386_devdesc *);
+	va_end(ap);
+	if (dev->d_kind.bioscd.unit >= nbcinfo) {
+		DEBUG("attempt to open nonexistent disk");
+		return(ENXIO);
+	}
+
+	return(0);
+}
+ 
+static int 
+bc_close(struct open_file *f)
+{
+
+	return(0);
+}
+
+static int 
+bc_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf,
+    size_t *rsize)
+{
+	struct i386_devdesc *dev;
+	int unit;
+	int blks;
+#ifdef BD_SUPPORT_FRAGS
+	char fragbuf[BIOSCD_SECSIZE];
+	size_t fragsize;
+
+	fragsize = size % BIOSCD_SECSIZE;
+#else
+	if (size % BIOSCD_SECSIZE)
+		return (EINVAL);
+#endif
+
+	if (rw != F_READ)
+		return(EROFS);
+	dev = (struct i386_devdesc *)devdata;
+	unit = dev->d_kind.bioscd.unit;
+	blks = size / BIOSCD_SECSIZE;
+	if (dblk % (BIOSCD_SECSIZE / DEV_BSIZE) != 0)
+		return (EINVAL);
+	dblk /= (BIOSCD_SECSIZE / DEV_BSIZE);
+	DEBUG("read %d from %d to %p", blks, dblk, buf);
+
+	if (rsize)
+		*rsize = 0;
+	if (blks && bc_read(unit, dblk, blks, buf)) {
+		DEBUG("read error");
+		return (EIO);
+	}
+#ifdef BD_SUPPORT_FRAGS
+	DEBUG("bc_strategy: frag read %d from %d+%d to %p", 
+	    fragsize, dblk, blks, buf + (blks * BIOSCD_SECSIZE));
+	if (fragsize && bc_read(unit, dblk + blks, 1, fragsize)) {
+		DEBUG("frag read error");
+		return(EIO);
+	}
+	bcopy(fragbuf, buf + (blks * BIOSCD_SECSIZE), fragsize);
+#endif	
+	if (rsize)
+		*rsize = size;
+	return (0);
+}
+
+static int
+bc_read(int unit, daddr_t dblk, int blks, caddr_t dest)
+{
+	u_int result, resid, retry;
+	static unsigned short packet[8];
+	int biosdev;
+#ifdef DISK_DEBUG
+	int error;
+#endif
+    
+	/* Just in case some idiot actually tries to read -1 blocks... */
+	if (blks < 0)
+		return (-1);
+
+	/* If nothing to do, just return succcess. */
+	if (blks == 0)
+		return (0);
+
+	biosdev = bc_unit2bios(unit);
+	/*
+	 * Loop retrying the operation a couple of times.  The BIOS
+	 * may also retry.
+	 */
+	for (retry = 0; retry < 3; retry++) {
+		/* If retrying, reset the drive */
+		if (retry > 0) {
+			v86.ctl = V86_FLAGS;
+			v86.addr = 0x13;
+			v86.eax = 0;
+			v86.edx = biosdev;
+			v86int();
+		}
+	    
+		packet[0] = 0x10;
+		packet[1] = blks;
+		packet[2] = VTOPOFF(dest);
+		packet[3] = VTOPSEG(dest);
+		packet[4] = dblk & 0xffff;
+		packet[5] = dblk >> 16;
+		packet[6] = 0;
+		packet[7] = 0;
+		v86.ctl = V86_FLAGS;
+		v86.addr = 0x13;
+		v86.eax = 0x4200;
+		v86.edx = biosdev;
+		v86.ds = VTOPSEG(packet);
+		v86.esi = VTOPOFF(packet);
+		v86int();
+		result = (v86.efl & PSL_C);
+		if (result == 0)
+			break;
+	}
+	
+#ifdef DISK_DEBUG
+	error = (v86.eax >> 8) & 0xff;
+#endif
+	DEBUG("%d sectors from %ld to %p (0x%x) %s", blks, dblk, dest,
+	    VTOP(dest), result ? "failed" : "ok");
+	DEBUG("unit %d  status 0x%x",  unit, error);
+	
+/*	hexdump(dest, (blks * BIOSCD_SECSIZE)); */
+	return(0);
+}
+
+/*
+ * Return a suitable dev_t value for (dev).
+ */
+int
+bc_getdev(struct i386_devdesc *dev)
+{
+    int biosdev, unit;
+    int major;
+    int rootdev;
+
+    unit = dev->d_kind.bioscd.unit;
+    biosdev = bc_unit2bios(unit);
+    DEBUG("unit %d BIOS device %d", unit, biosdev);
+    if (biosdev == -1)				/* not a BIOS device */
+	return(-1);
+
+    /*
+     * XXX: Need to examine device spec here to figure out if SCSI or
+     * ATAPI.  No idea on how to figure out device number.  All we can
+     * really pass to the kernel is what bus and device on which bus we
+     * were booted from, which dev_t isn't well suited to since those
+     * number don't match to unit numbers very well.  We may just need
+     * to engage in a hack where we pass -C to the boot args if we are
+     * the boot device.
+     */
+    major = ACDMAJOR;
+    unit = 0;	/* XXX */
+
+    /* XXX: Assume partition 'a'. */
+    rootdev = MAKEBOOTDEV(major, 0, 0, unit, 0);
+    DEBUG("dev is 0x%x\n", rootdev);
+    return(rootdev);
+}
diff --git a/sys/boot/i386/libi386/bootinfo.c b/sys/boot/i386/libi386/bootinfo.c
index 9b1368c..8e5c752 100644
--- a/sys/boot/i386/libi386/bootinfo.c
+++ b/sys/boot/i386/libi386/bootinfo.c
@@ -277,21 +277,30 @@ bi_load(char *args, int *howtop, int *bootdevp, vm_offset_t *bip)
     bootdevnr = 0;
 
     switch(rootdev->d_type) {
+    case DEVT_CD:
+	    /* Pass in BIOS device number. */
+	    bi.bi_bios_dev = bc_unit2bios(rootdev->d_kind.bioscd.unit);
+	    bootdevnr = bc_getdev(rootdev);
+	    if (bootdevnr != -1)
+		    *howtop |= RB_CDROM;
+	    break;
+
     case DEVT_DISK:
 	/* pass in the BIOS device number of the current disk */
 	bi.bi_bios_dev = bd_unit2bios(rootdev->d_kind.biosdisk.unit);
 	bootdevnr = bd_getdev(rootdev);
-	if (bootdevnr != -1)
-	    break;
-	printf("root device %s invalid\n", i386_fmtdev(rootdev));
-	return(EINVAL);
-	
+	break;
+
     case DEVT_NET:
 	    break;
 	    
     default:
 	printf("WARNING - don't know how to boot from device type %d\n", rootdev->d_type);
     }
+    if (bootdevnr == -1) {
+	printf("root device %s invalid\n", i386_fmtdev(rootdev));
+	return (EINVAL);
+    }
     free(rootdev);
     *bootdevp = bootdevnr;
 
diff --git a/sys/boot/i386/libi386/bootinfo32.c b/sys/boot/i386/libi386/bootinfo32.c
index 9b1368c..8e5c752 100644
--- a/sys/boot/i386/libi386/bootinfo32.c
+++ b/sys/boot/i386/libi386/bootinfo32.c
@@ -277,21 +277,30 @@ bi_load(char *args, int *howtop, int *bootdevp, vm_offset_t *bip)
     bootdevnr = 0;
 
     switch(rootdev->d_type) {
+    case DEVT_CD:
+	    /* Pass in BIOS device number. */
+	    bi.bi_bios_dev = bc_unit2bios(rootdev->d_kind.bioscd.unit);
+	    bootdevnr = bc_getdev(rootdev);
+	    if (bootdevnr != -1)
+		    *howtop |= RB_CDROM;
+	    break;
+
     case DEVT_DISK:
 	/* pass in the BIOS device number of the current disk */
 	bi.bi_bios_dev = bd_unit2bios(rootdev->d_kind.biosdisk.unit);
 	bootdevnr = bd_getdev(rootdev);
-	if (bootdevnr != -1)
-	    break;
-	printf("root device %s invalid\n", i386_fmtdev(rootdev));
-	return(EINVAL);
-	
+	break;
+
     case DEVT_NET:
 	    break;
 	    
     default:
 	printf("WARNING - don't know how to boot from device type %d\n", rootdev->d_type);
     }
+    if (bootdevnr == -1) {
+	printf("root device %s invalid\n", i386_fmtdev(rootdev));
+	return (EINVAL);
+    }
     free(rootdev);
     *bootdevp = bootdevnr;
 
diff --git a/sys/boot/i386/libi386/bootinfo64.c b/sys/boot/i386/libi386/bootinfo64.c
index 9b1368c..8e5c752 100644
--- a/sys/boot/i386/libi386/bootinfo64.c
+++ b/sys/boot/i386/libi386/bootinfo64.c
@@ -277,21 +277,30 @@ bi_load(char *args, int *howtop, int *bootdevp, vm_offset_t *bip)
     bootdevnr = 0;
 
     switch(rootdev->d_type) {
+    case DEVT_CD:
+	    /* Pass in BIOS device number. */
+	    bi.bi_bios_dev = bc_unit2bios(rootdev->d_kind.bioscd.unit);
+	    bootdevnr = bc_getdev(rootdev);
+	    if (bootdevnr != -1)
+		    *howtop |= RB_CDROM;
+	    break;
+
     case DEVT_DISK:
 	/* pass in the BIOS device number of the current disk */
 	bi.bi_bios_dev = bd_unit2bios(rootdev->d_kind.biosdisk.unit);
 	bootdevnr = bd_getdev(rootdev);
-	if (bootdevnr != -1)
-	    break;
-	printf("root device %s invalid\n", i386_fmtdev(rootdev));
-	return(EINVAL);
-	
+	break;
+
     case DEVT_NET:
 	    break;
 	    
     default:
 	printf("WARNING - don't know how to boot from device type %d\n", rootdev->d_type);
     }
+    if (bootdevnr == -1) {
+	printf("root device %s invalid\n", i386_fmtdev(rootdev));
+	return (EINVAL);
+    }
     free(rootdev);
     *bootdevp = bootdevnr;
 
diff --git a/sys/boot/i386/libi386/devicename.c b/sys/boot/i386/libi386/devicename.c
index dfa685e..31259c1 100644
--- a/sys/boot/i386/libi386/devicename.c
+++ b/sys/boot/i386/libi386/devicename.c
@@ -147,10 +147,11 @@ i386_parsedev(struct i386_devdesc **dev, const char *devspec, const char **path)
 	if (path != NULL)
 	    *path = (*cp == 0) ? cp : cp + 1;
 	break;
-	
+
+    case DEVT_CD:
     case DEVT_NET:
 	unit = 0;
-	
+
 	if (*np && (*np != ':')) {
 	    unit = strtol(np, &cp, 0);	/* get unit number if present */
 	    if (cp == np) {
@@ -162,8 +163,11 @@ i386_parsedev(struct i386_devdesc **dev, const char *devspec, const char **path)
 	    err = EINVAL;
 	    goto fail;
 	}
-	
-	idev->d_kind.netif.unit = unit;
+
+	if (dv->dv_type == DEVT_NET)
+	    idev->d_kind.netif.unit = unit;
+	else
+	    idev->d_kind.bioscd.unit = unit;
 	if (path != NULL)
 	    *path = (*cp == 0) ? cp : cp + 1;
 	break;
@@ -199,6 +203,10 @@ i386_fmtdev(void *vdev)
 	strcpy(buf, "(no device)");
 	break;
 
+    case DEVT_CD:
+	sprintf(buf, "%s%d:", dev->d_dev->dv_name, dev->d_kind.bioscd.unit);
+	break;
+
     case DEVT_DISK:
 	cp = buf;
 	cp += sprintf(cp, "%s%d", dev->d_dev->dv_name, dev->d_kind.biosdisk.unit);
diff --git a/sys/boot/i386/libi386/libi386.h b/sys/boot/i386/libi386/libi386.h
index 3f83bdc..cabe735 100644
--- a/sys/boot/i386/libi386/libi386.h
+++ b/sys/boot/i386/libi386/libi386.h
@@ -45,6 +45,11 @@ struct i386_devdesc
 	    int		partition;
 	    void	*data;
 	} biosdisk;
+	struct
+	{
+	    int		unit;
+	    void	*data;
+	} bioscd;
 	struct 
 	{
 	    int		unit;		/* XXX net layer lives over these? */
@@ -61,10 +66,15 @@ extern struct devdesc	currdev;	/* our current device */
 #define MAXDEV	31			/* maximum number of distinct devices */
 
 /* exported devices XXX rename? */
+extern struct devsw bioscd;
 extern struct devsw biosdisk;
 extern struct devsw pxedisk;
 extern struct fs_ops pxe_fsops;
 
+int	bc_add(int biosdev);		/* Register CD booted from. */
+int	bc_getdev(struct i386_devdesc *dev);	/* return dev_t for (dev) */
+int	bc_bios2unit(int biosdev);	/* xlate BIOS device -> bioscd unit */
+int	bc_unit2bios(int unit);		/* xlate bioscd unit -> BIOS device */
 u_int32_t	bd_getbigeom(int bunit);	/* return geometry in bootinfo format */
 int	bd_bios2unit(int biosdev);		/* xlate BIOS device -> biosdisk unit */
 int	bd_unit2bios(int unit);			/* xlate biosdisk unit -> BIOS device */