1/*
  2 *  fs/partitions/atari.c
  3 *
  4 *  Code extracted from drivers/block/genhd.c
  5 *
  6 *  Copyright (C) 1991-1998  Linus Torvalds
  7 *  Re-organised Feb 1998 Russell King
  8 */
  9
 10#include <linux/ctype.h>
 11#include "check.h"
 12#include "atari.h"
 13
 14/* ++guenther: this should be settable by the user ("make config")?.
 15 */
 16#define ICD_PARTS
 17
 18/* check if a partition entry looks valid -- Atari format is assumed if at
 19   least one of the primary entries is ok this way */
 20#define	VALID_PARTITION(pi,hdsiz)					     \
 21    (((pi)->flg & 1) &&							     \
 22     isalnum((pi)->id[0]) && isalnum((pi)->id[1]) && isalnum((pi)->id[2]) && \
 23     be32_to_cpu((pi)->st) <= (hdsiz) &&				     \
 24     be32_to_cpu((pi)->st) + be32_to_cpu((pi)->siz) <= (hdsiz))
 25
 26static inline int OK_id(char *s)
 27{
 28	return  memcmp (s, "GEM", 3) == 0 || memcmp (s, "BGM", 3) == 0 ||
 29		memcmp (s, "LNX", 3) == 0 || memcmp (s, "SWP", 3) == 0 ||
 30		memcmp (s, "RAW", 3) == 0 ;
 31}
 32
 33int atari_partition(struct parsed_partitions *state)
 34{
 35	Sector sect;
 36	struct rootsector *rs;
 37	struct partition_info *pi;
 38	u32 extensect;
 39	u32 hd_size;
 40	int slot;
 41#ifdef ICD_PARTS
 42	int part_fmt = 0; /* 0:unknown, 1:AHDI, 2:ICD/Supra */
 43#endif
 44
 45	rs = read_part_sector(state, 0, &sect);
 46	if (!rs)
 47		return -1;
 48
 49	/* Verify this is an Atari rootsector: */
 50	hd_size = state->bdev->bd_inode->i_size >> 9;
 51	if (!VALID_PARTITION(&rs->part[0], hd_size) &&
 52	    !VALID_PARTITION(&rs->part[1], hd_size) &&
 53	    !VALID_PARTITION(&rs->part[2], hd_size) &&
 54	    !VALID_PARTITION(&rs->part[3], hd_size)) {
 55		/*
 56		 * if there's no valid primary partition, assume that no Atari
 57		 * format partition table (there's no reliable magic or the like
 58	         * :-()
 59		 */
 60		put_dev_sector(sect);
 61		return 0;
 62	}
 63
 64	pi = &rs->part[0];
 65	strlcat(state->pp_buf, " AHDI", PAGE_SIZE);
 66	for (slot = 1; pi < &rs->part[4] && slot < state->limit; slot++, pi++) {
 67		struct rootsector *xrs;
 68		Sector sect2;
 69		ulong partsect;
 70
 71		if ( !(pi->flg & 1) )
 72			continue;
 73		/* active partition */
 74		if (memcmp (pi->id, "XGM", 3) != 0) {
 75			/* we don't care about other id's */
 76			put_partition (state, slot, be32_to_cpu(pi->st),
 77					be32_to_cpu(pi->siz));
 78			continue;
 79		}
 80		/* extension partition */
 81#ifdef ICD_PARTS
 82		part_fmt = 1;
 83#endif
 84		strlcat(state->pp_buf, " XGM<", PAGE_SIZE);
 85		partsect = extensect = be32_to_cpu(pi->st);
 86		while (1) {
 87			xrs = read_part_sector(state, partsect, &sect2);
 88			if (!xrs) {
 89				printk (" block %ld read failed\n", partsect);
 90				put_dev_sector(sect);
 91				return -1;
 92			}
 93
 94			/* ++roman: sanity check: bit 0 of flg field must be set */
 95			if (!(xrs->part[0].flg & 1)) {
 96				printk( "\nFirst sub-partition in extended partition is not valid!\n" );
 97				put_dev_sector(sect2);
 98				break;
 99			}
100
101			put_partition(state, slot,
102				   partsect + be32_to_cpu(xrs->part[0].st),
103				   be32_to_cpu(xrs->part[0].siz));
104
105			if (!(xrs->part[1].flg & 1)) {
106				/* end of linked partition list */
107				put_dev_sector(sect2);
108				break;
109			}
110			if (memcmp( xrs->part[1].id, "XGM", 3 ) != 0) {
111				printk("\nID of extended partition is not XGM!\n");
112				put_dev_sector(sect2);
113				break;
114			}
115
116			partsect = be32_to_cpu(xrs->part[1].st) + extensect;
117			put_dev_sector(sect2);
118			if (++slot == state->limit) {
119				printk( "\nMaximum number of partitions reached!\n" );
120				break;
121			}
122		}
123		strlcat(state->pp_buf, " >", PAGE_SIZE);
124	}
125#ifdef ICD_PARTS
126	if ( part_fmt!=1 ) { /* no extended partitions -> test ICD-format */
127		pi = &rs->icdpart[0];
128		/* sanity check: no ICD format if first partition invalid */
129		if (OK_id(pi->id)) {
130			strlcat(state->pp_buf, " ICD<", PAGE_SIZE);
131			for (; pi < &rs->icdpart[8] && slot < state->limit; slot++, pi++) {
132				/* accept only GEM,BGM,RAW,LNX,SWP partitions */
133				if (!((pi->flg & 1) && OK_id(pi->id)))
134					continue;
135				part_fmt = 2;
136				put_partition (state, slot,
137						be32_to_cpu(pi->st),
138						be32_to_cpu(pi->siz));
139			}
140			strlcat(state->pp_buf, " >", PAGE_SIZE);
141		}
142	}
143#endif
144	put_dev_sector(sect);
145
146	strlcat(state->pp_buf, "\n", PAGE_SIZE);
147
148	return 1;
149}