/*- * Copyright (c) 1998 Michael Smith * Copyright (c) 2012 Andrey V. Elsukov * 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 "disk.h" #include "libi386.h" CTASSERT(sizeof(struct i386_devdesc) >= sizeof(struct disk_devdesc)); #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 /* * List of BIOS devices, translation from disk unit number to * BIOS unit number. */ static struct bdinfo { int bd_unit; /* BIOS unit number */ int bd_cyl; /* BIOS geometry */ int bd_hds; int bd_sec; int bd_flags; #define BD_MODEINT13 0x0000 #define BD_MODEEDD1 0x0001 #define BD_MODEEDD3 0x0002 #define BD_MODEMASK 0x0003 #define BD_FLOPPY 0x0004 int bd_type; /* BIOS 'drive type' (floppy only) */ uint16_t bd_sectorsize; /* Sector size */ uint64_t bd_sectors; /* Disk size */ } bdinfo [MAXBDDEV]; static int nbdinfo = 0; #define BD(dev) (bdinfo[(dev)->d_unit]) static int bd_read(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest); static int bd_write(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest); static int bd_int13probe(struct bdinfo *bd); 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 int bd_ioctl(struct open_file *f, u_long cmd, void *data); static void bd_print(int verbose); static void bd_cleanup(void); struct devsw biosdisk = { "disk", DEVT_DISK, bd_init, bd_strategy, bd_open, bd_close, bd_ioctl, bd_print, bd_cleanup }; /* * 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, nfd = 0; /* sequence 0, 0x80 */ for (base = 0; base <= 0x80; base += 0x80) { for (unit = base; (nbdinfo < MAXBDDEV); unit++) { #ifndef VIRTUALBOX /* * Check the BIOS equipment list for number * of fixed disks. */ if(base == 0x80 && (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES))) break; #endif bdinfo[nbdinfo].bd_unit = unit; bdinfo[nbdinfo].bd_flags = unit < 0x80 ? BD_FLOPPY: 0; if (!bd_int13probe(&bdinfo[nbdinfo])) break; /* XXX we need "disk aliases" to make this simpler */ printf("BIOS drive %c: is disk%d\n", (unit < 0x80) ? ('A' + unit): ('C' + unit - 0x80), nbdinfo); nbdinfo++; if (base == 0x80) nfd++; } } return(0); } static void bd_cleanup(void) { disk_cleanup(&biosdisk); } /* * Try to detect a device supported by the legacy int13 BIOS */ static int bd_int13probe(struct bdinfo *bd) { struct edd_params params; v86.ctl = V86_FLAGS; v86.addr = 0x13; v86.eax = 0x800; v86.edx = bd->bd_unit; v86int(); if (V86_CY(v86.efl) || /* carry set */ (v86.ecx & 0x3f) == 0 || /* absurd sector number */ (v86.edx & 0xff) <= (unsigned)(bd->bd_unit & 0x7f)) /* unit # bad */ return (0); /* skip device */ /* Convert max cyl # -> # of cylinders */ bd->bd_cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1; /* Convert max head # -> # of heads */ bd->bd_hds = ((v86.edx & 0xff00) >> 8) + 1; bd->bd_sec = v86.ecx & 0x3f; bd->bd_type = v86.ebx & 0xff; bd->bd_flags |= BD_MODEINT13; /* Calculate sectors count from the geometry */ bd->bd_sectors = bd->bd_cyl * bd->bd_hds * bd->bd_sec; bd->bd_sectorsize = BIOSDISK_SECSIZE; DEBUG("unit 0x%x geometry %d/%d/%d", bd->bd_unit, bd->bd_cyl, bd->bd_hds, bd->bd_sec); /* Determine if we can use EDD with this device. */ v86.ctl = V86_FLAGS; v86.addr = 0x13; v86.eax = 0x4100; v86.edx = bd->bd_unit; v86.ebx = 0x55aa; v86int(); if (V86_CY(v86.efl) || /* carry set */ (v86.ebx & 0xffff) != 0xaa55 || /* signature */ (v86.ecx & EDD_INTERFACE_FIXED_DISK) == 0) return (1); /* EDD supported */ bd->bd_flags |= BD_MODEEDD1; if ((v86.eax & 0xff00) >= 0x3000) bd->bd_flags |= BD_MODEEDD3; /* Get disk params */ params.len = sizeof(struct edd_params); v86.ctl = V86_FLAGS; v86.addr = 0x13; v86.eax = 0x4800; v86.edx = bd->bd_unit; v86.ds = VTOPSEG(¶ms); v86.esi = VTOPOFF(¶ms); v86int(); if (!V86_CY(v86.efl)) { bd->bd_sectors = params.sectors; bd->bd_sectorsize = params.sector_size; } DEBUG("unit 0x%x flags %x, sectors %llu, sectorsize %u", bd->bd_unit, bd->bd_flags, bd->bd_sectors, bd->bd_sectorsize); return (1); } /* * Print information about disks */ static void bd_print(int verbose) { static char line[80]; struct disk_devdesc dev; int i; for (i = 0; i < nbdinfo; i++) { sprintf(line, " disk%d: BIOS drive %c:\n", i, (bdinfo[i].bd_unit < 0x80) ? ('A' + bdinfo[i].bd_unit): ('C' + bdinfo[i].bd_unit - 0x80)); pager_output(line); dev.d_dev = &biosdisk; dev.d_unit = i; dev.d_slice = -1; dev.d_partition = -1; if (disk_open(&dev, bdinfo[i].bd_sectorsize * bdinfo[i].bd_sectors, bdinfo[i].bd_sectorsize, (bdinfo[i].bd_flags & BD_FLOPPY) ? DISK_F_NOCACHE: 0) == 0) { sprintf(line, " disk%d", i); disk_print(&dev, line, verbose); disk_close(&dev); } } } /* * 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, ...) { struct disk_devdesc *dev; va_list ap; va_start(ap, f); dev = va_arg(ap, struct disk_devdesc *); va_end(ap); if (dev->d_unit < 0 || dev->d_unit >= nbdinfo) return (EIO); return (disk_open(dev, BD(dev).bd_sectors * BD(dev).bd_sectorsize, BD(dev).bd_sectorsize, (BD(dev).bd_flags & BD_FLOPPY) ? DISK_F_NOCACHE: 0)); } static int bd_close(struct open_file *f) { struct disk_devdesc *dev; dev = (struct disk_devdesc *)f->f_devdata; return (disk_close(dev)); } static int bd_ioctl(struct open_file *f, u_long cmd, void *data) { struct disk_devdesc *dev; dev = (struct disk_devdesc *)f->f_devdata; switch (cmd) { case DIOCGSECTORSIZE: *(u_int *)data = BD(dev).bd_sectorsize; break; case DIOCGMEDIASIZE: *(off_t *)data = BD(dev).bd_sectors * BD(dev).bd_sectorsize; break; default: return (ENOTTY); } return (0); } static int bd_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize) { struct bcache_devdata bcd; struct disk_devdesc *dev; dev = (struct disk_devdesc *)devdata; bcd.dv_strategy = bd_realstrategy; bcd.dv_devdata = devdata; return (bcache_strategy(&bcd, BD(dev).bd_unit, rw, dblk + dev->d_offset, size, buf, rsize)); } static int bd_realstrategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize) { struct disk_devdesc *dev = (struct disk_devdesc *)devdata; int blks; #ifdef BD_SUPPORT_FRAGS /* XXX: sector size */ char fragbuf[BIOSDISK_SECSIZE]; size_t fragsize; fragsize = size % BIOSDISK_SECSIZE; #else if (size % BD(dev).bd_sectorsize) panic("bd_strategy: %d bytes I/O not multiple of block size", size); #endif DEBUG("open_disk %p", dev); blks = size / BD(dev).bd_sectorsize; if (rsize) *rsize = 0; switch(rw){ case F_READ: DEBUG("read %d from %lld to %p", blks, dblk, buf); if (blks && bd_read(dev, dblk, blks, buf)) { DEBUG("read error"); return (EIO); } #ifdef BD_SUPPORT_FRAGS /* XXX: sector size */ 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(dev, 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_edd_io(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest, int write) { static struct edd_packet packet; packet.len = sizeof(struct edd_packet); packet.count = blks; packet.off = VTOPOFF(dest); packet.seg = VTOPSEG(dest); packet.lba = dblk; v86.ctl = V86_FLAGS; v86.addr = 0x13; if (write) /* Should we Write with verify ?? 0x4302 ? */ v86.eax = 0x4300; else v86.eax = 0x4200; v86.edx = BD(dev).bd_unit; v86.ds = VTOPSEG(&packet); v86.esi = VTOPOFF(&packet); v86int(); return (V86_CY(v86.efl)); } static int bd_chs_io(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest, int write) { u_int x, bpc, cyl, hd, sec; bpc = BD(dev).bd_sec * BD(dev).bd_hds; /* blocks per cylinder */ x = dblk; cyl = x / bpc; /* block # / blocks per cylinder */ x %= bpc; /* block offset into cylinder */ hd = x / BD(dev).bd_sec; /* offset / blocks per track */ sec = x % BD(dev).bd_sec; /* offset into track */ /* correct sector number for 1-based BIOS numbering */ sec++; if (cyl > 1023) /* CHS doesn't support cylinders > 1023. */ return (1); v86.ctl = V86_FLAGS; v86.addr = 0x13; if (write) v86.eax = 0x300 | blks; else v86.eax = 0x200 | blks; v86.ecx = ((cyl & 0xff) << 8) | ((cyl & 0x300) >> 2) | sec; v86.edx = (hd << 8) | BD(dev).bd_unit; v86.es = VTOPSEG(dest); v86.ebx = VTOPOFF(dest); v86int(); return (V86_CY(v86.efl)); } static int bd_io(struct disk_devdesc *dev, 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 || (BD(dev).bd_unit < 0x80 && (VTOP(dest) >> 16) != (VTOP(dest + blks * BD(dev).bd_sectorsize) >> 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(FLOPPY_BOUNCEBUF, (unsigned)blks); bbuf = alloca(x * 2 * BD(dev).bd_sectorsize); if (((u_int32_t)VTOP(bbuf) & 0xffff0000) == ((u_int32_t)VTOP(bbuf + x * BD(dev).bd_sectorsize) & 0xffff0000)) { breg = bbuf; } else { breg = bbuf + x * BD(dev).bd_sectorsize; } 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 % BD(dev).bd_sec; /* offset into track */ x = min(BD(dev).bd_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 * BD(dev).bd_sectorsize); /* * 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 = BD(dev).bd_unit; v86int(); } if (BD(dev).bd_flags & BD_MODEEDD1) result = bd_edd_io(dev, dblk, x, xp, write); else result = bd_chs_io(dev, 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 * BD(dev).bd_sectorsize); p += (x * BD(dev).bd_sectorsize); dblk += x; resid -= x; } /* hexdump(dest, (blks * BD(dev).bd_sectorsize)); */ return(0); } static int bd_read(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest) { return (bd_io(dev, dblk, blks, dest, 0)); } static int bd_write(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest) { return (bd_io(dev, dblk, blks, dest, 1)); } /* * 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) { v86.ctl = V86_FLAGS; v86.addr = 0x13; v86.eax = 0x800; v86.edx = 0x80 + bunit; v86int(); if (V86_CY(v86.efl)) return 0x4f010f; return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) | (v86.edx & 0xff00) | (v86.ecx & 0x3f); } /* * 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 *d) { struct disk_devdesc *dev; int biosdev; int major; int rootdev; char *nip, *cp; int i, unit; dev = (struct disk_devdesc *)d; 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 (disk_open(dev, BD(dev).bd_sectors * BD(dev).bd_sectorsize, BD(dev).bd_sectorsize,(BD(dev).bd_flags & BD_FLOPPY) ? DISK_F_NOCACHE: 0) != 0) /* oops, not a viable device */ return (-1); else disk_close(dev); if (biosdev < 0x80) { /* 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 { /* assume an IDE disk */ major = WDMAJOR; } /* default root disk unit number */ unit = biosdev & 0x7f; /* 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_slice + 1, unit, dev->d_partition); DEBUG("dev is 0x%x\n", rootdev); return(rootdev); }