WSL2-Linux-Kernel/fs/partitions/sgi.c

83 строки
2.2 KiB
C

/*
* fs/partitions/sgi.c
*
* Code extracted from drivers/block/genhd.c
*/
#include "check.h"
#include "sgi.h"
struct sgi_disklabel {
__be32 magic_mushroom; /* Big fat spliff... */
__be16 root_part_num; /* Root partition number */
__be16 swap_part_num; /* Swap partition number */
s8 boot_file[16]; /* Name of boot file for ARCS */
u8 _unused0[48]; /* Device parameter useless crapola.. */
struct sgi_volume {
s8 name[8]; /* Name of volume */
__be32 block_num; /* Logical block number */
__be32 num_bytes; /* How big, in bytes */
} volume[15];
struct sgi_partition {
__be32 num_blocks; /* Size in logical blocks */
__be32 first_block; /* First logical block */
__be32 type; /* Type of this partition */
} partitions[16];
__be32 csum; /* Disk label checksum */
__be32 _unused1; /* Padding */
};
int sgi_partition(struct parsed_partitions *state)
{
int i, csum;
__be32 magic;
int slot = 1;
unsigned int start, blocks;
__be32 *ui, cs;
Sector sect;
struct sgi_disklabel *label;
struct sgi_partition *p;
char b[BDEVNAME_SIZE];
label = read_part_sector(state, 0, &sect);
if (!label)
return -1;
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",
bdevname(bdev, b), be32_to_cpu(magic));*/
put_dev_sector(sect);
return 0;
}
ui = ((__be32 *) (label + 1)) - 1;
for(csum = 0; ui >= ((__be32 *) label);) {
cs = *ui--;
csum += be32_to_cpu(cs);
}
if(csum) {
printk(KERN_WARNING "Dev %s SGI disklabel: csum bad, label corrupted\n",
bdevname(state->bdev, b));
put_dev_sector(sect);
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) {
put_partition(state, slot, start, blocks);
if (be32_to_cpu(p->type) == LINUX_RAID_PARTITION)
state->parts[slot].flags = ADDPART_FLAG_RAID;
}
slot++;
}
printk("\n");
put_dev_sector(sect);
return 1;
}