atari.c

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/*
 *  fs/partitions/atari.c
 *
 *  Code extracted from drivers/block/genhd.c
 *
 *  Copyright (C) 1991-1998  Linus Torvalds
 *  Re-organised Feb 1998 Russell King
 */

#include <linux/ctype.h>
#include "check.h"
#include "atari.h"

/* ++guenther: this should be settable by the user ("make config")?.
 */
#define ICD_PARTS

/* check if a partition entry looks valid -- Atari format is assumed if at
   least one of the primary entries is ok this way */
#define VALID_PARTITION(pi,hdsiz)                        \
    (((pi)->flg & 1) &&                              \
     isalnum((pi)->id[0]) && isalnum((pi)->id[1]) && isalnum((pi)->id[2]) && \
     be32_to_cpu((pi)->st) <= (hdsiz) &&                     \
     be32_to_cpu((pi)->st) + be32_to_cpu((pi)->siz) <= (hdsiz))

static inline int OK_id(char *s)
{
    return  memcmp (s, "GEM", 3) == 0 || memcmp (s, "BGM", 3) == 0 ||
        memcmp (s, "LNX", 3) == 0 || memcmp (s, "SWP", 3) == 0 ||
        memcmp (s, "RAW", 3) == 0 ;
}

int atari_partition(struct parsed_partitions *state)
{
    Sector sect;
    struct rootsector *rs;
    struct partition_info *pi;
    u32 extensect;
    u32 hd_size;
    int slot;
#ifdef ICD_PARTS
    int part_fmt = 0; /* 0:unknown, 1:AHDI, 2:ICD/Supra */
#endif

    rs = read_part_sector(state, 0, &sect);
    if (!rs)
        return -1;

    /* Verify this is an Atari rootsector: */
    hd_size = state->bdev->bd_inode->i_size >> 9;
    if (!VALID_PARTITION(&rs->part[0], hd_size) &&
        !VALID_PARTITION(&rs->part[1], hd_size) &&
        !VALID_PARTITION(&rs->part[2], hd_size) &&
        !VALID_PARTITION(&rs->part[3], hd_size)) {
        /*
         * if there's no valid primary partition, assume that no Atari
         * format partition table (there's no reliable magic or the like
             * :-()
         */
        put_dev_sector(sect);
        return 0;
    }

    pi = &rs->part[0];
    strlcat(state->pp_buf, " AHDI", PAGE_SIZE);
    for (slot = 1; pi < &rs->part[4] && slot < state->limit; slot++, pi++) {
        struct rootsector *xrs;
        Sector sect2;
        ulong partsect;

        if ( !(pi->flg & 1) )
            continue;
        /* active partition */
        if (memcmp (pi->id, "XGM", 3) != 0) {
            /* we don't care about other id's */
            put_partition (state, slot, be32_to_cpu(pi->st),
                    be32_to_cpu(pi->siz));
            continue;
        }
        /* extension partition */
#ifdef ICD_PARTS
        part_fmt = 1;
#endif
        strlcat(state->pp_buf, " XGM<", PAGE_SIZE);
        partsect = extensect = be32_to_cpu(pi->st);
        while (1) {
            xrs = read_part_sector(state, partsect, &sect2);
            if (!xrs) {
                printk (" block %ld read failed\n", partsect);
                put_dev_sector(sect);
                return -1;
            }

            /* ++roman: sanity check: bit 0 of flg field must be set */
            if (!(xrs->part[0].flg & 1)) {
                printk( "\nFirst sub-partition in extended partition is not valid!\n" );
                put_dev_sector(sect2);
                break;
            }

            put_partition(state, slot,
                   partsect + be32_to_cpu(xrs->part[0].st),
                   be32_to_cpu(xrs->part[0].siz));

            if (!(xrs->part[1].flg & 1)) {
                /* end of linked partition list */
                put_dev_sector(sect2);
                break;
            }
            if (memcmp( xrs->part[1].id, "XGM", 3 ) != 0) {
                printk("\nID of extended partition is not XGM!\n");
                put_dev_sector(sect2);
                break;
            }

            partsect = be32_to_cpu(xrs->part[1].st) + extensect;
            put_dev_sector(sect2);
            if (++slot == state->limit) {
                printk( "\nMaximum number of partitions reached!\n" );
                break;
            }
        }
        strlcat(state->pp_buf, " >", PAGE_SIZE);
    }
#ifdef ICD_PARTS
    if ( part_fmt!=1 ) { /* no extended partitions -> test ICD-format */
        pi = &rs->icdpart[0];
        /* sanity check: no ICD format if first partition invalid */
        if (OK_id(pi->id)) {
            strlcat(state->pp_buf, " ICD<", PAGE_SIZE);
            for (; pi < &rs->icdpart[8] && slot < state->limit; slot++, pi++) {
                /* accept only GEM,BGM,RAW,LNX,SWP partitions */
                if (!((pi->flg & 1) && OK_id(pi->id)))
                    continue;
                part_fmt = 2;
                put_partition (state, slot,
                        be32_to_cpu(pi->st),
                        be32_to_cpu(pi->siz));
            }
            strlcat(state->pp_buf, " >", PAGE_SIZE);
        }
    }
#endif
    put_dev_sector(sect);

    strlcat(state->pp_buf, "\n", PAGE_SIZE);

    return 1;
}