Display all possible partitions when the root filesystem is not mounted. This helps to track spell'o's and missing drivers.
From: David Alan Gilbert, http://lkml.org/lkml/2005/2/26/92 Updated to work with newer kernels. Signed-off-by: Jan Engelhardt <[EMAIL PROTECTED]> block/genhd.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/genhd.h | 1 init/do_mounts.c | 7 +++++- 3 files changed, 61 insertions(+), 1 deletion(-) Index: linux-2.6.21-rc5/block/genhd.c =================================================================== --- linux-2.6.21-rc5.orig/block/genhd.c +++ linux-2.6.21-rc5/block/genhd.c @@ -215,6 +215,60 @@ struct gendisk *get_gendisk(dev_t dev, i return kobj ? to_disk(kobj) : NULL; } +/* + * printk a full list of all partitions - intended for + * places where the root filesystem can't be mounted and thus + * to give the victim some idea of what went wrong + */ +void printk_all_partitions(void) +{ + int n; + struct gendisk* sgp; + mutex_lock(&block_subsys_lock); + + /* For each block device... */ + list_for_each_entry(sgp, &block_subsys.kset.list, kobj.entry) { + char buf[BDEVNAME_SIZE]; + /* + * Don't show empty devices or things that have been surpressed + */ + if (get_capacity(sgp) && + !(sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)) { + /* + * Note, unlike /proc/partitions I am showing the + * numbers in hex in the same format as the root= + * option + */ + printk("%02x%02x %10llu %s", + sgp->major, sgp->first_minor, + (unsigned long long)get_capacity(sgp) >> 1, + disk_name(sgp, 0, buf)); + if ((sgp->driverfs_dev) && + (sgp->driverfs_dev->driver)) { + printk(" driver: %s\n", + sgp->driverfs_dev->driver->name); + } else { + printk(" (driver?)\n"); + } + + /* now show the partitions */ + for (n = 0; n < sgp->minors - 1; ++n) { + if (!sgp->part[n]) + continue; + if (sgp->part[n]->nr_sects == 0) + continue; + printk(" %02x%02x %10llu %s\n", + sgp->major, n + 1 + sgp->first_minor, + (unsigned long long)sgp->part[n]->nr_sects >> 1 , + disk_name(sgp, n + 1, buf)); + } /* partition subloop */ + } /* Non 0 size, not surpressed */ + } /* Block device loop */ + + mutex_unlock(&block_subsys_lock); + return; +} + #ifdef CONFIG_PROC_FS /* iterator */ static void *part_start(struct seq_file *part, loff_t *pos) Index: linux-2.6.21-rc5/include/linux/genhd.h =================================================================== --- linux-2.6.21-rc5.orig/include/linux/genhd.h +++ linux-2.6.21-rc5/include/linux/genhd.h @@ -413,6 +413,7 @@ char *disk_name (struct gendisk *hd, int extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev); extern void add_partition(struct gendisk *, int, sector_t, sector_t, int); extern void delete_partition(struct gendisk *, int); +extern void printk_all_partitions(void); extern struct gendisk *alloc_disk_node(int minors, int node_id); extern struct gendisk *alloc_disk(int minors); Index: linux-2.6.21-rc5/init/do_mounts.c =================================================================== --- linux-2.6.21-rc5.orig/init/do_mounts.c +++ linux-2.6.21-rc5/init/do_mounts.c @@ -7,6 +7,7 @@ #include <linux/root_dev.h> #include <linux/security.h> #include <linux/delay.h> +#include <linux/genhd.h> #include <linux/mount.h> #include <linux/device.h> @@ -307,17 +308,21 @@ retry: /* * Allow the user to distinguish between failed sys_open * and bad superblock on root device. + * and give them a list of the available devices */ #ifdef CONFIG_BLOCK __bdevname(ROOT_DEV, b); #endif printk("VFS: Cannot open root device \"%s\" or %s\n", root_device_name, b); - printk("Please append a correct \"root=\" boot option\n"); + printk("Please append a correct \"root=\" boot option; here are the available partitions:\n"); + printk_all_partitions(); panic("VFS: Unable to mount root fs on %s", b); } + printk("List of all partitions:\n"); + printk_all_partitions(); printk("No filesystem could mount root, tried: "); for (p = fs_names; *p; p += strlen(p)+1) printk(" %s", p); #<EOF> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
