raid autodetect for sun disk labels
PATCH 1/1 raid autodetect for sun disk labels
I wasn't terribly fond of the idea of needing an initrd or weird
boot options to support root raid on a sparc, so I hacked on the sun disk label support a bit to pass "Linux raid autodetect" partitions up to md. The extra breakout of the disk label struct is from the fdisk source, hopefully it's not obsolete. With this I can boot to a root raid0 on a sparc 10, but it should of course work on any set of disks w/ proper magic. Patch attached for 2.4.20-pre7/8. Please CC on followup. Thanks,
Alex Williamson
fs/partitions/sun.c renamed from fs/partitions/sun.c~ +20 -2
@@ -19,6 +19,10 @@#include "check.h" #include "sun.h" +#if CONFIG_BLK_DEV_MD +extern void md_autodetect_dev (kdev_t dev); +#endif +int sun_partition (struct gendisk *hd,struct block_device *bdev,unsigned long first_sector,int first_part_minor) {int i, csum;
@@ -27,7 +31,14 @@kdev_t dev =to_kdev_t (bdev->bd_dev);struct sun_disklabel {unsigned char info[128 ];/* Informative text string */ -unsigned char spare[292 ];/* Boot information etc. */ +unsigned char spare0[14 ]; +struct sun_info { +unsigned char spare1; +unsigned char id; +unsigned char spare2; +unsigned char flags; + } infos[8 ]; +unsigned char spare[246 ];/* Boot information etc. */ unsigned short rspeed;/* Disk rotational speed */ unsigned short pcylcount;/* Physical cylinder count */ unsigned short sparecyl;/* extra sects per cylinder */
@@ -69,6 +80,7 @@put_dev_sector (sect);return 0 ; } +/* All Sun disks have 8 partition entries */ spc =be16_to_cpu (label->ntrks) *be16_to_cpu (label->nsect);for (i=0 ; i <8 ; i++, p++) {
@@ -77,8 +89,14 @@ st_sector = first_sector +be32_to_cpu (p->start_cylinder) * spc; num_sectors =be32_to_cpu (p->num_sectors); -if (num_sectors) +if (num_sectors) {add_gd_partition (hd, first_part_minor, st_sector, num_sectors); +#if CONFIG_BLK_DEV_MD +if (label->infos[i].id ==0xfd ) {/* "Linux raid autodetect" */ +md_autodetect_dev (MKDEV (hd->major, first_part_minor)); + } +#endif + } first_part_minor++; }printk ("\n" );
Nice work, I put this into my tree and I will pass it on to Marcelo and Linus.
The only changes I made were:
1) Include linux/config.h
2) Use LINUX_RAID_PARTITION instead of magic constant
Thanks again.
partitions/sun.c renamed from partitions/sun.c.~1~ +25 -5
@@ -7,6 +7,7 @@* Re-organised Feb 1998 Russell King */ +#include <linux/config.h> #include <linux/fs.h> #include <linux/genhd.h> #include <linux/kernel.h>
@@ -19,6 +20,10 @@#include "check.h" #include "sun.h" +#ifdef CONFIG_BLK_DEV_MD +extern void md_autodetect_dev (kdev_t dev); +#endif +int sun_partition (struct gendisk *hd,struct block_device *bdev,unsigned long first_sector,int first_part_minor) {int i, csum;
@@ -27,7 +32,14 @@kdev_t dev =to_kdev_t (bdev->bd_dev);struct sun_disklabel {unsigned char info[128 ];/* Informative text string */ -unsigned char spare[292 ];/* Boot information etc. */ +unsigned char sparc0[14 ]; +struct sun_info { +unsigned char spare1; +unsigned char id; +unsigned char spare2; +unsigned char flags; + } infos[8 ]; +unsigned char spare[246 ];/* Boot information etc. */ unsigned short rspeed;/* Disk rotational speed */ unsigned short pcylcount;/* Physical cylinder count */ unsigned short sparecyl;/* extra sects per cylinder */
@@ -63,22 +75,30 @@ ush = ((unsigned short *) (label+1 )) -1 ;for (csum =0 ; ush >= ((unsigned short *) label);) csum ^= *ush--; -if (csum) { +if (csum) {printk ("Dev %s Sun disklabel: Csum bad, label corrupted\n" ,bdevname (dev));put_dev_sector (sect);return 0 ; } +/* All Sun disks have 8 partition entries */ spc =be16_to_cpu (label->ntrks) *be16_to_cpu (label->nsect); -for (i=0 ; i <8 ; i++, p++) { +for (i =0 ; i <8 ; i++, p++) {unsigned long st_sector;int num_sectors; st_sector = first_sector +be32_to_cpu (p->start_cylinder) * spc; num_sectors =be32_to_cpu (p->num_sectors); -if (num_sectors) -add_gd_partition (hd, first_part_minor, st_sector, num_sectors); +if (num_sectors) { +add_gd_partition (hd, first_part_minor, + st_sector, num_sectors); +#ifdef CONFIG_BLK_DEV_MD +if (label->infos[i].id ==LINUX_RAID_PARTITION ) +md_autodetect_dev (MKDEV (hd->major, + first_part_minor)); +#endif + } first_part_minor++; }printk ("\n" );