--- /dev/null
+/*
+ * NEC PC-9800 series partition supports
+ *
+ * Copyright (C) 1999 Kyoto University Microcomputer Club
+ */
+
+#include <linux/config.h>
+#include <linux/fs.h>
+#include <linux/genhd.h>
+#include <linux/kernel.h>
+#include <linux/blk.h>
+#include <linux/hdreg.h>
+
+#include "check.h"
+#include "nec98.h"
+
+struct nec98_partition {
+ __u8 mid; /* 0x80 - active */
+ __u8 sid; /* 0x80 - bootable */
+ __u16 pad1; /* dummy for padding */
+ __u8 ipl_sector; /* IPL sector */
+ __u8 ipl_head; /* IPL head */
+ __u16 ipl_cyl; /* IPL cylinder */
+ __u8 sector; /* starting sector */
+ __u8 head; /* starting head */
+ __u16 cyl; /* starting cylinder */
+ __u8 end_sector; /* end sector */
+ __u8 end_head; /* end head */
+ __u16 end_cyl; /* end cylinder */
+ unsigned char name[16];
+} __attribute__((__packed__));
+
+#define NEC98_BSD_PARTITION_MID 0x14
+#define NEC98_BSD_PARTITION_SID 0x44
+#define MID_SID_16(mid, sid) (((mid) & 0xFF) | (((sid) & 0xFF) << 8))
+#define NEC98_BSD_PARTITION_MID_SID \
+ MID_SID_16(NEC98_BSD_PARTITION_MID, NEC98_BSD_PARTITION_SID)
+#define NEC98_VALID_PTABLE_ENTRY(P) \
+ (!(P)->pad1 && (P)->cyl <= (P)->end_cyl)
+
+extern int pc98_bios_param(struct block_device *bdev, int *ip);
+
+static inline int
+is_valid_nec98_partition_table(const struct nec98_partition *ptable,
+ __u8 nsectors, __u8 nheads)
+{
+ int i;
+ int valid = 0;
+
+ for (i = 0; i < 16; i++) {
+ if (!*(__u16 *)&ptable[i])
+ continue; /* empty slot */
+ if (ptable[i].pad1 /* `pad1' contains junk */
+ || ptable[i].ipl_sector >= nsectors
+ || ptable[i].sector >= nsectors
+ || ptable[i].end_sector >= nsectors
+ || ptable[i].ipl_head >= nheads
+ || ptable[i].head >= nheads
+ || ptable[i].end_head >= nheads
+ || ptable[i].cyl > ptable[i].end_cyl)
+ return 0;
+ valid = 1; /* We have a valid partition. */
+ }
+ /* If no valid PC-9800-style partitions found,
+ the disk may have other type of partition table. */
+ return valid;
+}
+
+#ifdef CONFIG_BSD_DISKLABEL
+extern void parse_bsd(struct parsed_partitions *state,
+ struct block_device *bdev,
+ u32 offset, u32 size, int origin, char *flavour,
+ int max_partitions);
+#endif
+
+int nec98_partition(struct parsed_partitions *state, struct block_device *bdev)
+{
+ unsigned int nr;
+ struct hd_geometry geo;
+ Sector sect;
+ const struct nec98_partition *part;
+ unsigned char *data;
+ int sector_size = bdev_hardsect_size(bdev);
+ int major = MAJOR(bdev->bd_dev);
+
+ if (ioctl_by_bdev(bdev, HDIO_GETGEO, (unsigned long)&geo) != 0) {
+ printk(" unsupported disk (major = %u)\n", major);
+ return 0;
+ }
+
+#ifdef NEC98_PARTITION_DEBUG
+ printk("ioctl_by_bdev head=%d sect=%d\n", geo.heads, geo.sectors);
+#endif
+ data = read_dev_sector(bdev, 0, §);
+ if (!data) {
+ if (warn_no_part)
+ printk(" unable to read partition table\n");
+ return -1;
+ }
+
+ /* magic(?) check */
+ if (*(__u16 *)(data + sector_size - 2) != NEC98_PTABLE_MAGIC) {
+ put_dev_sector(sect);
+ return 0;
+ }
+
+ put_dev_sector(sect);
+ data = read_dev_sector(bdev, 1, §);
+ if (!data) {
+ if (warn_no_part)
+ printk(" unable to read partition table\n");
+ return -1;
+ }
+
+ if (!is_valid_nec98_partition_table((struct nec98_partition *)data,
+ geo.sectors, geo.heads)) {
+#ifdef NEC98_PARTITION_DEBUG
+ if (warn_no_part)
+ printk(" partition table consistency check failed"
+ " (not PC-9800 disk?)\n");
+#endif
+ put_dev_sector(sect);
+ return 0;
+ }
+
+ part = (const struct nec98_partition *)data;
+ for (nr = 0; nr < 16; nr++, part++) {
+ unsigned int start_sect, end_sect;
+
+ if (part->mid == 0 || part->sid == 0)
+ continue;
+
+ if (nr)
+ printk(" ");
+
+ { /* Print partition name. Fdisk98 might put NUL
+ characters in partition name... */
+
+ int j;
+ unsigned char *p;
+ unsigned char buf[sizeof (part->name) * 2 + 1];
+
+ for (p = buf, j = 0; j < sizeof (part->name); j++, p++)
+ if ((*p = part->name[j]) < ' ') {
+ *p++ = '^';
+ *p = part->name[j] + '@';
+ }
+
+ *p = 0;
+ printk(" <%s>", buf);
+ }
+ start_sect = (part->cyl * geo.heads + part->head) * geo.sectors
+ + part->sector;
+ end_sect = (part->end_cyl + 1) * geo.heads * geo.sectors;
+ if (end_sect <= start_sect) {
+ printk(" (invalid partition info)\n");
+ continue;
+ }
+
+ put_partition(state, nr + 1, start_sect, end_sect - start_sect);
+#ifdef CONFIG_BSD_DISKLABEL
+ if ((*(__u16 *)&part->mid & 0x7F7F)
+ == NEC98_BSD_PARTITION_MID_SID) {
+ printk("!");
+ /* NEC98_BSD_PARTITION_MID_SID is not valid SYSIND for
+ IBM PC's MS-DOS partition table, so we simply pass
+ it to bsd_disklabel_partition;
+ it will just print `<bsd: ... >'. */
+ parse_bsd(state, bdev, start_sect,
+ end_sect - start_sect, nr + 1,
+ "bsd98", BSD_MAXPARTITIONS);
+ }
+#endif
+ { /* Pretty size printing. */
+ /* XXX sector size? */
+ unsigned int psize = (end_sect - start_sect) / 2;
+ int unit_char = 'K';
+
+ if (psize > 99999) {
+ psize >>= 10;
+ unit_char = 'M';
+ }
+ printk(" %5d%cB (%5d-%5d)\n",
+ psize, unit_char, part->cyl, part->end_cyl);
+ }
+ }
+
+ put_dev_sector(sect);
+
+ return nr ? 1 : 0;
+}
+\f
+/*
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */
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