// SPDX-License-Identifier: GPL-2.0

  /*
   *  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

  	/*
  	 * ATARI partition scheme supports 512 lba only.  If this is not
  	 * the case, bail early to avoid miscalculating hd_size.
  	 */
  	if (bdev_logical_block_size(state->bdev) != 512)
  		return 0;

  	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
  ", 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( "
  First sub-partition in extended partition is not valid!
  " );
  				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("
  ID of extended partition is not XGM!
  ");
  				put_dev_sector(sect2);
  				break;
  			}
  
  			partsect = be32_to_cpu(xrs->part[1].st) + extensect;
  			put_dev_sector(sect2);
  			if (++slot == state->limit) {
  				printk( "
  Maximum number of partitions reached!
  " );
  				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, "
  ", PAGE_SIZE);

  
  	return 1;
  }