patch-2.3.14 linux/fs/partitions/sgi.c

• Lines: 87
• Date: Thu Aug 12 12:26:06 1999
• Orig file: v2.3.13/linux/fs/partitions/sgi.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.13/linux/fs/partitions/sgi.c linux/fs/partitions/sgi.c
@@ -0,0 +1,86 @@
+/*
+ *  fs/partitions/sgi.c
+ *
+ *  Code extracted from drivers/block/genhd.c
+ */
+
+#include <linux/fs.h>
+#include <linux/genhd.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/string.h>
+#include <linux/blk.h>
+
+#include <asm/byteorder.h>
+#include <asm/system.h>
+
+#include "check.h"
+#include "sgi.h"
+
+int sgi_partition(struct gendisk *hd, kdev_t dev, unsigned long first_sector, int first_part_minor)
+{
+	int i, csum, magic, current_minor = first_part_minor;
+	unsigned int *ui, start, blocks, cs;
+	struct buffer_head *bh;
+	struct sgi_disklabel {
+		int magic_mushroom;         /* Big fat spliff... */
+		short root_part_num;        /* Root partition number */
+		short swap_part_num;        /* Swap partition number */
+		char boot_file[16];         /* Name of boot file for ARCS */
+		unsigned char _unused0[48]; /* Device parameter useless crapola.. */
+		struct sgi_volume {
+			char name[8];       /* Name of volume */
+			int  block_num;     /* Logical block number */
+			int  num_bytes;     /* How big, in bytes */
+		} volume[15];
+		struct sgi_partition {
+			int num_blocks;     /* Size in logical blocks */
+			int first_block;    /* First logical block */
+			int type;           /* Type of this partition */
+		} partitions[16];
+		int csum;                   /* Disk label checksum */
+		int _unused1;               /* Padding */
+	} *label;
+	struct sgi_partition *p;
+
+	if(!(bh = bread(dev, 0, get_ptable_blocksize(dev)))) {
+		printk("Dev %s: unable to read partition table\n", kdevname(dev));
+		return -1;
+	}
+	label = (struct sgi_disklabel *) bh->b_data;
+	p = &label->partitions[0];
+	magic = label->magic_mushroom;
+	if(be32_to_cpu(magic) != SGI_LABEL_MAGIC) {
+		printk("Dev %s SGI disklabel: bad magic %08x\n",
+		       kdevname(dev), magic);
+		brelse(bh);
+		return 0;
+	}
+	ui = ((unsigned int *) (label + 1)) - 1;
+	for(csum = 0; ui >= ((unsigned int *) label);) {
+		cs = *ui--;
+		csum += be32_to_cpu(cs);
+	}
+	if(csum) {
+		printk("Dev %s SGI disklabel: csum bad, label corrupted\n",
+		       kdevname(dev));
+		brelse(bh);
+		return 0;
+	}
+	/* All SGI disk labels have 16 partitions, disks under Linux only
+	 * have 15 minor's.  Luckily there are always a few zero length
+	 * partitions which we don't care about so we never overflow the
+	 * current_minor.
+	 */
+	for(i = 0; i < 16; i++, p++) {
+		blocks = be32_to_cpu(p->num_blocks);
+		start  = be32_to_cpu(p->first_block);
+		if(!blocks)
+			continue;
+		add_gd_partition(hd, current_minor, start, blocks);
+		current_minor++;
+	}
+	printk("\n");
+	brelse(bh);
+	return 1;
+}