[Comm] Как ядро заставить пересчитать устройство?

[Pavel Vainerman]

17.09.2013 12:46, Kharitonov A. Dmitry пишет:
> Требуется получить получить адекватный UUID
>
> Вставляю SD карту
> $ dmesg | tail
> [  289.425392] sd 4:0:0:0: [sde] Mode Sense: 03 00 00 00
> [  289.426736] sd 4:0:0:0: [sde] No Caching mode page present
> [  289.426757] sd 4:0:0:0: [sde] Assuming drive cache: write through
> [  289.436518] sd 4:0:0:0: [sde] No Caching mode page present
> [  289.436536] sd 4:0:0:0: [sde] Assuming drive cache: write through
> [  289.439109]  sde: sde1 sde2 < sde5 >
> [  289.444068] sd 4:0:0:0: [sde] No Caching mode page present
> [  289.444092] sd 4:0:0:0: [sde] Assuming drive cache: write through
> [  289.444114] sd 4:0:0:0: [sde] Attached SCSI removable disk
> [  290.576258] FAT-fs (sde1): utf8 is not a recommended IO charset for
> FAT filesystems, filesystem will be case sensitive!
> $ sudo fdisk -l /dev/sde
>
> Disk /dev/sde: 32.3 GB, 32295092224 bytes, 63076352 sectors
> Units = sectors of 1 * 512 = 512 bytes
> Sector size (logical/physical): 512 bytes / 512 bytes
> I/O size (minimum/optimal): 512 bytes / 512 bytes
> Disk identifier: 0x001105d9
>
>     Device Boot      Start         End      Blocks   Id  System
> /dev/sde1            2048     6293503     3145728    c  W95 FAT32 (LBA)
> /dev/sde2         6293504    63076351    28391424    f  W95 Ext'd (LBA)
> /dev/sde5         6295552    63076351    28390400    b  W95 FAT32
> $ sudo blkid | grep /dev/sde
> /dev/sde1: LABEL="tr" UUID="C725-949A" TYPE="vfat"
> /dev/sde5: LABEL="tr2" UUID="C885-03E6" TYPE="vfat"
>
> Внимательно смотрим на UUID="C725-949A"
> Это всё правильно. Теперь мне нужно переформатировать в ntfs
>
> $ sudo umount /dev/sde1
> $ sudo umount /dev/sde1
> umount: /dev/sde1: not mounted
> $ sudo umount /dev/sde5
> umount: /dev/sde5: not mounted
> $ sudo dd if=/dev/zero of=/dev/sde count=8k bs=4096
> 8192+0 records in
> 8192+0 records out
> 33554432 bytes (34 MB) copied, 2.94593 s, 11.4 MB/s
> $ echo -ne "u\nc\nn\np\n\n\n\nt\n7\na\n1\nw\n" | sudo fdisk -S56 /dev/sde
> Welcome to fdisk (util-linux 2.22.1).
>
> Changes will remain in memory only, until you decide to write them.
> Be careful before using the write command.
>
> Device does not contain a recognized partition table
> Building a new DOS disklabel with disk identifier 0x218d0787.
>
> Command (m for help): Changing display/entry units to cylinders
> (DEPRECATED!)
>
> Command (m for help): DOS Compatibility flag is set (DEPRECATED!)
>
> Command (m for help): Partition type:
>     p   primary (0 primary, 0 extended, 4 free)
>     e   extended
> Select (default p): Partition number (1-4, default 1): Using default
> value 1
> First cylinder (1-17599, default 1): Using default value 1
> Last cylinder, +cylinders or +size{K,M,G} (1-17599, default 17599):
> Using default value 17599
> Partition 1 of type Linux and of size 30.1 GiB is set
>
> Command (m for help): Selected partition 1
> Hex code (type L to list codes): Changed system type of partition 1 to 7
> (HPFS/NTFS/exFAT)
>
> Command (m for help): Partition number (1-4):
> Command (m for help): The partition table has been altered!
>
> Calling ioctl() to re-read partition table.
> Syncing disks.
> $ sudo fdisk -l /dev/sde
>
> Disk /dev/sde: 32.3 GB, 32295092224 bytes, 63076352 sectors
> Units = sectors of 1 * 512 = 512 bytes
> Sector size (logical/physical): 512 bytes / 512 bytes
> I/O size (minimum/optimal): 512 bytes / 512 bytes
> Disk identifier: 0x218d0787
>
>     Device Boot      Start         End      Blocks   Id  System
> /dev/sde1   *          56    63074815    31537380    7 HPFS/NTFS/exFAT
> $ sudo mkfs.ntfs -f -c 4096 -L test /dev/sde1
> Creating NTFS volume structures.
> mkntfs completed successfully. Have a nice day.
>
> А теперь внимание
>
> $ sudo blkid | grep /dev/sde
> /dev/sde1: LABEL="tr" UUID="C725-949A" TYPE="vfat"
>
> UUID не изменился!!!
>
> $ sudo partprobe
> $ sudo blkid | grep /dev/sde
> /dev/sde1: LABEL="tr" UUID="C725-949A" TYPE="vfat"
>
> вынимаю и вставляю
>
> $ dmesg | tail
> [  918.870892] sd 5:0:0:0: [sde] Write Protect is off
> [  918.870910] sd 5:0:0:0: [sde] Mode Sense: 03 00 00 00
> [  918.872078] sd 5:0:0:0: [sde] No Caching mode page present
> [  918.872093] sd 5:0:0:0: [sde] Assuming drive cache: write through
> [  918.877223] sd 5:0:0:0: [sde] No Caching mode page present
> [  918.877233] sd 5:0:0:0: [sde] Assuming drive cache: write through
> [  918.878631]  sde: sde1
> [  918.882372] sd 5:0:0:0: [sde] No Caching mode page present
> [  918.882382] sd 5:0:0:0: [sde] Assuming drive cache: write through
> [  918.882390] sd 5:0:0:0: [sde] Attached SCSI removable disk
> $ sudo blkid | grep /dev/sde
> /dev/sde1: LABEL="tr" UUID="C725-949A" TYPE="vfat"
>
>
> После перезагрузки
>
> $ dmesg | tail
> [  139.522377] sd 4:0:0:0: [sde] Mode Sense: 03 00 00 00
> [  139.523479] sd 4:0:0:0: [sde] No Caching mode page present
> [  139.523495] sd 4:0:0:0: [sde] Assuming drive cache: write through
> [  139.531353] sd 4:0:0:0: [sde] No Caching mode page present
> [  139.531369] sd 4:0:0:0: [sde] Assuming drive cache: write through
> [  139.532754]  sde: sde1
> [  139.536356] sd 4:0:0:0: [sde] No Caching mode page present
> [  139.536369] sd 4:0:0:0: [sde] Assuming drive cache: write through
> [  139.536381] sd 4:0:0:0: [sde] Attached SCSI removable disk
> [  144.687148] fuse init (API version 7.20)
> $ sudo blkid | grep /dev/sde
> /dev/sde1: LABEL="test" UUID="2130BC3E3BF9C94B" TYPE="ntfs"
>
> За какую ручку дёргать чтоб не перезагружаться?

  наверно возможно так
	blockdev --rereadpt /dev/sde

-- 
Pavel Vainerman
www.etersot.ru