/*- * Copyright (c) 1998 Michael Smith * 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. */ #include __FBSDID("$FreeBSD$"); /* * BIOS disk device handling. * * Ideas and algorithms from: * * - NetBSD libi386/biosdisk.c * - FreeBSD biosboot/disk.c * */ #include #include #include #include #include #include #include #include "libi386.h" #define BIOS_NUMDRIVES 0x475 #define BIOSDISK_SECSIZE 512 #define BUFSIZE (1 * BIOSDISK_SECSIZE) #define DT_ATAPI 0x10 /* disk type for ATAPI floppies */ #define WDMAJOR 0 /* major numbers for devices we frontend for */ #define WFDMAJOR 1 #define FDMAJOR 2 #define DAMAJOR 4 #ifdef DISK_DEBUG # define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __func__ , ## args) #else # define DEBUG(fmt, args...) #endif struct open_disk { int od_dkunit; /* disk unit number */ int od_unit; /* BIOS unit number */ int od_cyl; /* BIOS geometry */ int od_hds; int od_sec; int od_boff; /* block offset from beginning of BIOS disk */ int od_flags; #define BD_MODEINT13 0x0000 #define BD_MODEEDD1 0x0001 #define BD_MODEEDD3 0x0002 #define BD_MODEMASK 0x0003 #define BD_FLOPPY 0x0004 #define BD_LABELOK 0x0008 #define BD_PARTTABOK 0x0010 #define BD_OPTICAL 0x0020 struct disklabel od_disklabel; int od_nslices; /* slice count */ struct pc98_partition od_slicetab[PC98_NPARTS]; }; /* * List of BIOS devices, translation from disk unit number to * BIOS unit number. */ static struct bdinfo { int bd_unit; /* BIOS unit number */ int bd_flags; int bd_type; /* BIOS 'drive type' (floppy only) */ int bd_da_unit; /* kernel unit number for da */ } bdinfo [MAXBDDEV]; static int nbdinfo = 0; static int bd_getgeom(struct open_disk *od); static int bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest); static int bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest); static int bd_int13probe(struct bdinfo *bd); static void bd_printslice(struct open_disk *od, struct pc98_partition *dp, char *prefix, int verbose); static void bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix, int verbose); static int bd_init(void); static int bd_strategy(void *devdata, int flag, daddr_t dblk, size_t size, char *buf, size_t *rsize); static int bd_realstrategy(void *devdata, int flag, daddr_t dblk, size_t size, char *buf, size_t *rsize); static int bd_open(struct open_file *f, ...); static int bd_close(struct open_file *f); static void bd_print(int verbose); struct devsw biosdisk = { "disk", DEVT_DISK, bd_init, bd_strategy, bd_open, bd_close, noioctl, bd_print, NULL }; static int bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev); static void bd_closedisk(struct open_disk *od); static int bd_open_pc98(struct open_disk *od, struct i386_devdesc *dev); static int bd_bestslice(struct open_disk *od); static void bd_checkextended(struct open_disk *od, int slicenum); /* * Translate between BIOS device numbers and our private unit numbers. */ int bd_bios2unit(int biosdev) { int i; DEBUG("looking for bios device 0x%x", biosdev); for (i = 0; i < nbdinfo; i++) { DEBUG("bd unit %d is BIOS device 0x%x", i, bdinfo[i].bd_unit); if (bdinfo[i].bd_unit == biosdev) return(i); } return(-1); } int bd_unit2bios(int unit) { if ((unit >= 0) && (unit < nbdinfo)) return(bdinfo[unit].bd_unit); return(-1); } /* * Quiz the BIOS for disk devices, save a little info about them. */ static int bd_init(void) { int base, unit; int da_drive=0, n=-0x10; /* sequence 0x90, 0x80, 0xa0 */ for (base = 0x90; base <= 0xa0; base += n, n += 0x30) { for (unit = base; (nbdinfo < MAXBDDEV) || ((unit & 0x0f) < 4); unit++) { bdinfo[nbdinfo].bd_unit = unit; bdinfo[nbdinfo].bd_flags = (unit & 0xf0) == 0x90 ? BD_FLOPPY : 0; if (!bd_int13probe(&bdinfo[nbdinfo])){ if (((unit & 0xf0) == 0x90 && (unit & 0x0f) < 4) || ((unit & 0xf0) == 0xa0 && (unit & 0x0f) < 6)) continue; /* Target IDs are not contiguous. */ else break; } if (bdinfo[nbdinfo].bd_flags & BD_FLOPPY){ /* available 1.44MB access? */ if (*(u_char *)PTOV(0xA15AE) & (1<<(unit & 0xf))) { /* boot media 1.2MB FD? */ if ((*(u_char *)PTOV(0xA1584) & 0xf0) != 0x90) bdinfo[nbdinfo].bd_unit = 0x30 + (unit & 0xf); } } else { if ((unit & 0xF0) == 0xA0) /* SCSI HD or MO */ bdinfo[nbdinfo].bd_da_unit = da_drive++; } /* XXX we need "disk aliases" to make this simpler */ printf("BIOS drive %c: is disk%d\n", 'A' + nbdinfo, nbdinfo); nbdinfo++; } } return(0); } /* * Try to detect a device supported by the legacy int13 BIOS */ static int bd_int13probe(struct bdinfo *bd) { int addr; if (bd->bd_flags & BD_FLOPPY) { addr = 0xa155c; } else { if ((bd->bd_unit & 0xf0) == 0x80) addr = 0xa155d; else addr = 0xa1482; } if ( *(u_char *)PTOV(addr) & (1<<(bd->bd_unit & 0x0f))) { bd->bd_flags |= BD_MODEINT13; return(1); } if ((bd->bd_unit & 0xF0) == 0xA0) { int media = ((unsigned *)PTOV(0xA1460))[bd->bd_unit & 0x0F] & 0x1F; if (media == 7) { /* MO */ bd->bd_flags |= BD_MODEINT13 | BD_OPTICAL; return(1); } } return(0); } /* * Print information about disks */ static void bd_print(int verbose) { int i, j; char line[80]; struct i386_devdesc dev; struct open_disk *od; struct pc98_partition *dptr; for (i = 0; i < nbdinfo; i++) { sprintf(line, " disk%d: BIOS drive %c:\n", i, 'A' + i); pager_output(line); /* try to open the whole disk */ dev.d_unit = i; dev.d_kind.biosdisk.slice = -1; dev.d_kind.biosdisk.partition = -1; if (!bd_opendisk(&od, &dev)) { /* Do we have a partition table? */ if (od->od_flags & BD_PARTTABOK) { dptr = &od->od_slicetab[0]; /* Check for a "dedicated" disk */ for (j = 0; j < od->od_nslices; j++) { sprintf(line, " disk%ds%d", i, j + 1); bd_printslice(od, &dptr[j], line, verbose); } } bd_closedisk(od); } } } /* Given a size in 512 byte sectors, convert it to a human-readable number. */ static char * display_size(uint64_t size) { static char buf[80]; char unit; size /= 2; unit = 'K'; if (size >= 10485760000LL) { size /= 1073741824; unit = 'T'; } else if (size >= 10240000) { size /= 1048576; unit = 'G'; } else if (size >= 10000) { size /= 1024; unit = 'M'; } sprintf(buf, "%6ld%cB", (long)size, unit); return (buf); } /* * Print information about slices on a disk. For the size calculations we * assume a 512 byte sector. */ static void bd_printslice(struct open_disk *od, struct pc98_partition *dp, char *prefix, int verbose) { int cylsecs, start, size; char stats[80]; char line[80]; cylsecs = od->od_hds * od->od_sec; start = dp->dp_scyl * cylsecs + dp->dp_shd * od->od_sec + dp->dp_ssect; size = (dp->dp_ecyl - dp->dp_scyl + 1) * cylsecs; if (verbose) sprintf(stats, " %s (%d - %d)", display_size(size), start, start + size); else stats[0] = '\0'; switch(dp->dp_mid & PC98_MID_MASK) { case PC98_MID_386BSD: bd_printbsdslice(od, start, prefix, verbose); return; case 0x00: /* unused partition */ return; case 0x01: sprintf(line, "%s: FAT-12%s\n", prefix, stats); break; case 0x11: case 0x20: case 0x21: case 0x22: case 0x23: case 0x24: sprintf(line, "%s: FAT-16%s\n", prefix, stats); break; default: sprintf(line, "%s: Unknown fs: 0x%x %s\n", prefix, dp->dp_mid, stats); } pager_output(line); } /* * Print out each valid partition in the disklabel of a FreeBSD slice. * For size calculations, we assume a 512 byte sector size. */ static void bd_printbsdslice(struct open_disk *od, daddr_t offset, char *prefix, int verbose) { char line[80]; char buf[BIOSDISK_SECSIZE]; struct disklabel *lp; int i; /* read disklabel */ if (bd_read(od, offset + LABELSECTOR, 1, buf)) return; lp =(struct disklabel *)(&buf[0]); if (lp->d_magic != DISKMAGIC) { sprintf(line, "%s: FFS bad disklabel\n", prefix); pager_output(line); return; } /* Print partitions */ for (i = 0; i < lp->d_npartitions; i++) { /* * For each partition, make sure we know what type of fs it is. If * not, then skip it. However, since floppies often have bogus * fstypes, print the 'a' partition on a floppy even if it is marked * unused. */ if ((lp->d_partitions[i].p_fstype == FS_BSDFFS) || (lp->d_partitions[i].p_fstype == FS_SWAP) || (lp->d_partitions[i].p_fstype == FS_VINUM) || ((lp->d_partitions[i].p_fstype == FS_UNUSED) && (od->od_flags & BD_FLOPPY) && (i == 0))) { /* Only print out statistics in verbose mode */ if (verbose) sprintf(line, " %s%c: %s %s (%d - %d)\n", prefix, 'a' + i, (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap " : (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" : "FFS ", display_size(lp->d_partitions[i].p_size), lp->d_partitions[i].p_offset, lp->d_partitions[i].p_offset + lp->d_partitions[i].p_size); else sprintf(line, " %s%c: %s\n", prefix, 'a' + i, (lp->d_partitions[i].p_fstype == FS_SWAP) ? "swap" : (lp->d_partitions[i].p_fstype == FS_VINUM) ? "vinum" : "FFS"); pager_output(line); } } } /* * Attempt to open the disk described by (dev) for use by (f). * * Note that the philosophy here is "give them exactly what * they ask for". This is necessary because being too "smart" * about what the user might want leads to complications. * (eg. given no slice or partition value, with a disk that is * sliced - are they after the first BSD slice, or the DOS * slice before it?) */ static int bd_open(struct open_file *f, ...) { va_list ap; struct i386_devdesc *dev; struct open_disk *od; int error; va_start(ap, f); dev = va_arg(ap, struct i386_devdesc *); va_end(ap); if ((error = bd_opendisk(&od, dev))) return(error); /* * Save our context */ ((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data = od; DEBUG("open_disk %p, partition at 0x%x", od, od->od_boff); return(0); } static int bd_opendisk(struct open_disk **odp, struct i386_devdesc *dev) { struct open_disk *od; int error; if (dev->d_unit >= nbdinfo) { DEBUG("attempt to open nonexistent disk"); return(ENXIO); } od = (struct open_disk *)malloc(sizeof(struct open_disk)); if (!od) { DEBUG("no memory"); return (ENOMEM); } /* Look up BIOS unit number, intialise open_disk structure */ od->od_dkunit = dev->d_unit; od->od_unit = bdinfo[od->od_dkunit].bd_unit; od->od_flags = bdinfo[od->od_dkunit].bd_flags; od->od_boff = 0; error = 0; DEBUG("open '%s', unit 0x%x slice %d partition %d", i386_fmtdev(dev), dev->d_unit, dev->d_kind.biosdisk.slice, dev->d_kind.biosdisk.partition); /* Get geometry for this open (removable device may have changed) */ if (bd_getgeom(od)) { DEBUG("can't get geometry"); error = ENXIO; goto out; } /* Determine disk layout. */ error = bd_open_pc98(od, dev); out: if (error) { free(od); } else { *odp = od; /* return the open disk */ } return(error); } static int bd_open_pc98(struct open_disk *od, struct i386_devdesc *dev) { struct pc98_partition *dptr; struct disklabel *lp; int sector, slice, i; char buf[BUFSIZE]; /* * Following calculations attempt to determine the correct value * for d->od_boff by looking for the slice and partition specified, * or searching for reasonable defaults. */ /* * Find the slice in the DOS slice table. */ od->od_nslices = 0; if (od->od_flags & BD_FLOPPY) { sector = 0; goto unsliced; } if (bd_read(od, 0, 1, buf)) { DEBUG("error reading MBR"); return (EIO); } /* * Check the slice table magic. */ if (((u_char)buf[0x1fe] != 0x55) || ((u_char)buf[0x1ff] != 0xaa)) { /* If a slice number was explicitly supplied, this is an error */ if (dev->d_kind.biosdisk.slice > 0) { DEBUG("no slice table/MBR (no magic)"); return (ENOENT); } sector = 0; goto unsliced; /* may be a floppy */ } if (bd_read(od, 1, 1, buf)) { DEBUG("error reading MBR"); return (EIO); } /* * copy the partition table, then pick up any extended partitions. */ bcopy(buf + PC98_PARTOFF, &od->od_slicetab, sizeof(struct pc98_partition) * PC98_NPARTS); od->od_nslices = PC98_NPARTS; /* extended slices start here */ od->od_flags |= BD_PARTTABOK; dptr = &od->od_slicetab[0]; /* Is this a request for the whole disk? */ if (dev->d_kind.biosdisk.slice == -1) { sector = 0; goto unsliced; } /* * if a slice number was supplied but not found, this is an error. */ if (dev->d_kind.biosdisk.slice > 0) { slice = dev->d_kind.biosdisk.slice - 1; if (slice >= od->od_nslices) { DEBUG("slice %d not found", slice); return (ENOENT); } } /* Try to auto-detect the best slice; this should always give a slice number */ if (dev->d_kind.biosdisk.slice == 0) { slice = bd_bestslice(od); if (slice == -1) { return (ENOENT); } dev->d_kind.biosdisk.slice = slice; } dptr = &od->od_slicetab[0]; /* * Accept the supplied slice number unequivocally (we may be looking * at a DOS partition). */ dptr += (dev->d_kind.biosdisk.slice - 1); /* we number 1-4, offsets are 0-3 */ sector = dptr->dp_scyl * od->od_hds * od->od_sec + dptr->dp_shd * od->od_sec + dptr->dp_ssect; { int end = dptr->dp_ecyl * od->od_hds * od->od_sec + dptr->dp_ehd * od->od_sec + dptr->dp_esect; DEBUG("slice entry %d at %d, %d sectors", dev->d_kind.biosdisk.slice - 1, sector, end-sector); } /* * If we are looking at a BSD slice, and the partition is < 0, assume the 'a' partition */ if ((dptr->dp_mid == DOSMID_386BSD) && (dev->d_kind.biosdisk.partition < 0)) dev->d_kind.biosdisk.partition = 0; unsliced: /* * Now we have the slice offset, look for the partition in the disklabel if we have * a partition to start with. * * XXX we might want to check the label checksum. */ if (dev->d_kind.biosdisk.partition < 0) { od->od_boff = sector; /* no partition, must be after the slice */ DEBUG("opening raw slice"); } else { if (bd_read(od, sector + LABELSECTOR, 1, buf)) { DEBUG("error reading disklabel"); return (EIO); } DEBUG("copy %d bytes of label from %p to %p", sizeof(struct disklabel), buf + LABELOFFSET, &od->od_disklabel); bcopy(buf + LABELOFFSET, &od->od_disklabel, sizeof(struct disklabel)); lp = &od->od_disklabel; od->od_flags |= BD_LABELOK; if (lp->d_magic != DISKMAGIC) { DEBUG("no disklabel"); return (ENOENT); } if (dev->d_kind.biosdisk.partition >= lp->d_npartitions) { DEBUG("partition '%c' exceeds partitions in table (a-'%c')", 'a' + dev->d_kind.biosdisk.partition, 'a' + lp->d_npartitions); return (EPART); } #ifdef DISK_DEBUG /* Complain if the partition is unused unless this is a floppy. */ if ((lp->d_partitions[dev->d_kind.biosdisk.partition].p_fstype == FS_UNUSED) && !(od->od_flags & BD_FLOPPY)) DEBUG("warning, partition marked as unused"); #endif od->od_boff = lp->d_partitions[dev->d_kind.biosdisk.partition].p_offset - lp->d_partitions[RAW_PART].p_offset + sector; } return (0); } /* * Search for a slice with the following preferences: * * 1: Active FreeBSD slice * 2: Non-active FreeBSD slice * 3: Active Linux slice * 4: non-active Linux slice * 5: Active FAT/FAT32 slice * 6: non-active FAT/FAT32 slice */ #define PREF_RAWDISK 0 #define PREF_FBSD_ACT 1 #define PREF_FBSD 2 #define PREF_LINUX_ACT 3 #define PREF_LINUX 4 #define PREF_DOS_ACT 5 #define PREF_DOS 6 #define PREF_NONE 7 /* * slicelimit is in the range 0 .. PC98_NPARTS */ static int bd_bestslice(struct open_disk *od) { struct pc98_partition *dp; int pref, preflevel; int i, prefslice; prefslice = 0; preflevel = PREF_NONE; dp = &od->od_slicetab[0]; for (i = 0; i < od->od_nslices; i++, dp++) { switch(dp->dp_mid & PC98_MID_MASK) { case PC98_MID_386BSD: /* FreeBSD */ if ((dp->dp_mid & PC98_MID_BOOTABLE) && (preflevel > PREF_FBSD_ACT)) { pref = i; preflevel = PREF_FBSD_ACT; } else if (preflevel > PREF_FBSD) { pref = i; preflevel = PREF_FBSD; } break; case 0x11: /* DOS/Windows */ case 0x20: case 0x21: case 0x22: case 0x23: case 0x63: if ((dp->dp_mid & PC98_MID_BOOTABLE) && (preflevel > PREF_DOS_ACT)) { pref = i; preflevel = PREF_DOS_ACT; } else if (preflevel > PREF_DOS) { pref = i; preflevel = PREF_DOS; } break; } } return (prefslice); } static int bd_close(struct open_file *f) { struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)(f->f_devdata))->d_kind.biosdisk.data); bd_closedisk(od); return(0); } static void bd_closedisk(struct open_disk *od) { DEBUG("open_disk %p", od); #if 0 /* XXX is this required? (especially if disk already open...) */ if (od->od_flags & BD_FLOPPY) delay(3000000); #endif free(od); } static int bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize) { struct bcache_devdata bcd; struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data); bcd.dv_strategy = bd_realstrategy; bcd.dv_devdata = devdata; return(bcache_strategy(&bcd, od->od_unit, rw, dblk+od->od_boff, size, buf, rsize)); } static int bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize) { struct open_disk *od = (struct open_disk *)(((struct i386_devdesc *)devdata)->d_kind.biosdisk.data); int blks; #ifdef BD_SUPPORT_FRAGS char fragbuf[BIOSDISK_SECSIZE]; size_t fragsize; fragsize = size % BIOSDISK_SECSIZE; #else if (size % BIOSDISK_SECSIZE) panic("bd_strategy: %d bytes I/O not multiple of block size", size); #endif DEBUG("open_disk %p", od); blks = size / BIOSDISK_SECSIZE; if (rsize) *rsize = 0; switch(rw){ case F_READ: DEBUG("read %d from %d to %p", blks, dblk, buf); if (blks && bd_read(od, dblk, blks, buf)) { DEBUG("read error"); return (EIO); } #ifdef BD_SUPPORT_FRAGS DEBUG("bd_strategy: frag read %d from %d+%d to %p", fragsize, dblk, blks, buf + (blks * BIOSDISK_SECSIZE)); if (fragsize && bd_read(od, dblk + blks, 1, fragsize)) { DEBUG("frag read error"); return(EIO); } bcopy(fragbuf, buf + (blks * BIOSDISK_SECSIZE), fragsize); #endif break; case F_WRITE : DEBUG("write %d from %d to %p", blks, dblk, buf); if (blks && bd_write(od, dblk, blks, buf)) { DEBUG("write error"); return (EIO); } #ifdef BD_SUPPORT_FRAGS if(fragsize) { DEBUG("Attempted to write a frag"); return (EIO); } #endif break; default: /* DO NOTHING */ return (EROFS); } if (rsize) *rsize = size; return (0); } /* Max number of sectors to bounce-buffer if the request crosses a 64k boundary */ #define FLOPPY_BOUNCEBUF 18 static int bd_chs_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write) { u_int x, bpc, cyl, hd, sec; bpc = (od->od_sec * od->od_hds); /* blocks per cylinder */ x = dblk; cyl = x / bpc; /* block # / blocks per cylinder */ x %= bpc; /* block offset into cylinder */ hd = x / od->od_sec; /* offset / blocks per track */ sec = x % od->od_sec; /* offset into track */ v86.ctl = V86_FLAGS; v86.addr = 0x1b; if (write) v86.eax = 0x0500 | od->od_unit; else v86.eax = 0x0600 | od->od_unit; if (od->od_flags & BD_FLOPPY) { v86.eax |= 0xd000; v86.ecx = 0x0200 | (cyl & 0xff); v86.edx = (hd << 8) | (sec + 1); } else if (od->od_flags & BD_OPTICAL) { v86.eax &= 0xFF7F; v86.ecx = dblk & 0xFFFF; v86.edx = dblk >> 16; } else { v86.ecx = cyl; v86.edx = (hd << 8) | sec; } v86.ebx = blks * BIOSDISK_SECSIZE; v86.es = VTOPSEG(dest); v86.ebp = VTOPOFF(dest); v86int(); return (v86.efl & 0x1); } static int bd_io(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest, int write) { u_int x, sec, result, resid, retry, maxfer; caddr_t p, xp, bbuf, breg; /* Just in case some idiot actually tries to read/write -1 blocks... */ if (blks < 0) return (-1); resid = blks; p = dest; /* Decide whether we have to bounce */ if (VTOP(dest) >> 20 != 0 || ((VTOP(dest) >> 16) != (VTOP(dest + blks * BIOSDISK_SECSIZE) >> 16))) { /* * There is a 64k physical boundary somewhere in the * destination buffer, or the destination buffer is above * first 1MB of physical memory so we have to arrange a * suitable bounce buffer. Allocate a buffer twice as large * as we need to. Use the bottom half unless there is a break * there, in which case we use the top half. */ x = min(od->od_sec, (unsigned)blks); bbuf = alloca(x * 2 * BIOSDISK_SECSIZE); if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == ((u_int32_t)VTOP(bbuf + x * BIOSDISK_SECSIZE) & 0xffff0000)) { breg = bbuf; } else { breg = bbuf + x * BIOSDISK_SECSIZE; } maxfer = x; /* limit transfers to bounce region size */ } else { breg = bbuf = NULL; maxfer = 0; } while (resid > 0) { /* * Play it safe and don't cross track boundaries. * (XXX this is probably unnecessary) */ sec = dblk % od->od_sec; /* offset into track */ x = min(od->od_sec - sec, resid); if (maxfer > 0) x = min(x, maxfer); /* fit bounce buffer */ /* where do we transfer to? */ xp = bbuf == NULL ? p : breg; /* * Put your Data In, Put your Data out, * Put your Data In, and shake it all about */ if (write && bbuf != NULL) bcopy(p, breg, x * BIOSDISK_SECSIZE); /* * 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 = 0x1b; v86.eax = 0x0300 | od->od_unit; v86int(); } result = bd_chs_io(od, dblk, x, xp, write); if (result == 0) break; } if (write) DEBUG("Write %d sector(s) from %p (0x%x) to %lld %s", x, p, VTOP(p), dblk, result ? "failed" : "ok"); else DEBUG("Read %d sector(s) from %lld to %p (0x%x) %s", x, dblk, p, VTOP(p), result ? "failed" : "ok"); if (result) { return(-1); } if (!write && bbuf != NULL) bcopy(breg, p, x * BIOSDISK_SECSIZE); p += (x * BIOSDISK_SECSIZE); dblk += x; resid -= x; } /* hexdump(dest, (blks * BIOSDISK_SECSIZE)); */ return(0); } static int bd_read(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest) { return (bd_io(od, dblk, blks, dest, 0)); } static int bd_write(struct open_disk *od, daddr_t dblk, int blks, caddr_t dest) { return (bd_io(od, dblk, blks, dest, 1)); } static int bd_getgeom(struct open_disk *od) { if (od->od_flags & BD_FLOPPY) { od->od_cyl = 79; od->od_hds = 2; od->od_sec = (od->od_unit & 0xf0) == 0x30 ? 18 : 15; } else if (od->od_flags & BD_OPTICAL) { od->od_cyl = 0xFFFE; od->od_hds = 8; od->od_sec = 32; } else { v86.ctl = V86_FLAGS; v86.addr = 0x1b; v86.eax = 0x8400 | od->od_unit; v86int(); od->od_cyl = v86.ecx; od->od_hds = (v86.edx >> 8) & 0xff; od->od_sec = v86.edx & 0xff; if (v86.efl & 0x1) return(1); } DEBUG("unit 0x%x geometry %d/%d/%d", od->od_unit, od->od_cyl, od->od_hds, od->od_sec); return(0); } /* * Return the BIOS geometry of a given "fixed drive" in a format * suitable for the legacy bootinfo structure. Since the kernel is * expecting raw int 0x13/0x8 values for N_BIOS_GEOM drives, we * prefer to get the information directly, rather than rely on being * able to put it together from information already maintained for * different purposes and for a probably different number of drives. * * For valid drives, the geometry is expected in the format (31..0) * "000000cc cccccccc hhhhhhhh 00ssssss"; and invalid drives are * indicated by returning the geometry of a "1.2M" PC-format floppy * disk. And, incidentally, what is returned is not the geometry as * such but the highest valid cylinder, head, and sector numbers. */ u_int32_t bd_getbigeom(int bunit) { int hds = 0; int unit = 0x80; /* IDE HDD */ u_int addr = 0xA155d; while (unit < 0xa7) { if (*(u_char *)PTOV(addr) & (1 << (unit & 0x0f))) if (hds++ == bunit) break; if (unit >= 0xA0) { int media = ((unsigned *)PTOV(0xA1460))[unit & 0x0F] & 0x1F; if (media == 7 && hds++ == bunit) /* SCSI MO */ return(0xFFFE0820); /* C:65535 H:8 S:32 */ } if (++unit == 0x84) { unit = 0xA0; /* SCSI HDD */ addr = 0xA1482; } } if (unit == 0xa7) return 0x4F020F; /* 1200KB FD C:80 H:2 S:15 */ v86.ctl = V86_FLAGS; v86.addr = 0x1b; v86.eax = 0x8400 | unit; v86int(); if (v86.efl & 0x1) return 0x4F020F; /* 1200KB FD C:80 H:2 S:15 */ return ((v86.ecx & 0xffff) << 16) | (v86.edx & 0xffff); } /* * Return a suitable dev_t value for (dev). * * In the case where it looks like (dev) is a SCSI disk, we allow the number of * IDE disks to be specified in $num_ide_disks. There should be a Better Way. */ int bd_getdev(struct i386_devdesc *dev) { struct open_disk *od; int biosdev; int major; int rootdev; char *nip, *cp; int unitofs = 0, i, unit; biosdev = bd_unit2bios(dev->d_unit); DEBUG("unit %d BIOS device %d", dev->d_unit, biosdev); if (biosdev == -1) /* not a BIOS device */ return(-1); if (bd_opendisk(&od, dev) != 0) /* oops, not a viable device */ return(-1); if ((biosdev & 0xf0) == 0x90 || (biosdev & 0xf0) == 0x30) { /* floppy (or emulated floppy) or ATAPI device */ if (bdinfo[dev->d_unit].bd_type == DT_ATAPI) { /* is an ATAPI disk */ major = WFDMAJOR; } else { /* is a floppy disk */ major = FDMAJOR; } } else { /* harddisk */ if ((od->od_flags & BD_LABELOK) && (od->od_disklabel.d_type == DTYPE_SCSI)) { /* label OK, disk labelled as SCSI */ major = DAMAJOR; /* check for unit number correction hint, now deprecated */ if ((nip = getenv("num_ide_disks")) != NULL) { i = strtol(nip, &cp, 0); /* check for parse error */ if ((cp != nip) && (*cp == 0)) unitofs = i; } } else { /* assume an IDE disk */ major = WDMAJOR; } } /* default root disk unit number */ if ((biosdev & 0xf0) == 0xa0) unit = bdinfo[dev->d_unit].bd_da_unit; else unit = biosdev & 0xf; /* XXX a better kludge to set the root disk unit number */ if ((nip = getenv("root_disk_unit")) != NULL) { i = strtol(nip, &cp, 0); /* check for parse error */ if ((cp != nip) && (*cp == 0)) unit = i; } rootdev = MAKEBOOTDEV(major, dev->d_kind.biosdisk.slice + 1, unit, dev->d_kind.biosdisk.partition); DEBUG("dev is 0x%x\n", rootdev); return(rootdev); }