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1// SPDX-License-Identifier: GPL-2.02/*3 * fs/partitions/sgi.c4 *5 * Code extracted from drivers/block/genhd.c6 */7 8#include "check.h"9 10#define SGI_LABEL_MAGIC 0x0be5a94111 12enum {13 LINUX_RAID_PARTITION = 0xfd, /* autodetect RAID partition */14};15 16struct sgi_disklabel {17 __be32 magic_mushroom; /* Big fat spliff... */18 __be16 root_part_num; /* Root partition number */19 __be16 swap_part_num; /* Swap partition number */20 s8 boot_file[16]; /* Name of boot file for ARCS */21 u8 _unused0[48]; /* Device parameter useless crapola.. */22 struct sgi_volume {23 s8 name[8]; /* Name of volume */24 __be32 block_num; /* Logical block number */25 __be32 num_bytes; /* How big, in bytes */26 } volume[15];27 struct sgi_partition {28 __be32 num_blocks; /* Size in logical blocks */29 __be32 first_block; /* First logical block */30 __be32 type; /* Type of this partition */31 } partitions[16];32 __be32 csum; /* Disk label checksum */33 __be32 _unused1; /* Padding */34};35 36int sgi_partition(struct parsed_partitions *state)37{38 int i, csum;39 __be32 magic;40 int slot = 1;41 unsigned int start, blocks;42 __be32 *ui, cs;43 Sector sect;44 struct sgi_disklabel *label;45 struct sgi_partition *p;46 47 label = read_part_sector(state, 0, §);48 if (!label)49 return -1;50 p = &label->partitions[0];51 magic = label->magic_mushroom;52 if(be32_to_cpu(magic) != SGI_LABEL_MAGIC) {53 /*printk("Dev %s SGI disklabel: bad magic %08x\n",54 state->disk->disk_name, be32_to_cpu(magic));*/55 put_dev_sector(sect);56 return 0;57 }58 ui = ((__be32 *) (label + 1)) - 1;59 for(csum = 0; ui >= ((__be32 *) label);) {60 cs = *ui--;61 csum += be32_to_cpu(cs);62 }63 if(csum) {64 printk(KERN_WARNING "Dev %s SGI disklabel: csum bad, label corrupted\n",65 state->disk->disk_name);66 put_dev_sector(sect);67 return 0;68 }69 /* All SGI disk labels have 16 partitions, disks under Linux only70 * have 15 minor's. Luckily there are always a few zero length71 * partitions which we don't care about so we never overflow the72 * current_minor.73 */74 for(i = 0; i < 16; i++, p++) {75 blocks = be32_to_cpu(p->num_blocks);76 start = be32_to_cpu(p->first_block);77 if (blocks) {78 put_partition(state, slot, start, blocks);79 if (be32_to_cpu(p->type) == LINUX_RAID_PARTITION)80 state->parts[slot].flags = ADDPART_FLAG_RAID;81 }82 slot++;83 }84 strlcat(state->pp_buf, "\n", PAGE_SIZE);85 put_dev_sector(sect);86 return 1;87}88