include/zfs/vdev_impl.h

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 1999,2000,2001,2002,2003,2004  Free Software Foundation, Inc.
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7 /*
   8  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
   9  * Use is subject to license terms.
  10  */
  11
  12 #ifndef _SYS_VDEV_IMPL_H
  13 #define _SYS_VDEV_IMPL_H
  14
  15 #define VDEV_SKIP_SIZE          (8 << 10)
  16 #define VDEV_BOOT_HEADER_SIZE   (8 << 10)
  17 #define VDEV_PHYS_SIZE          (112 << 10)
  18 #define VDEV_UBERBLOCK_RING     (128 << 10)
  19
  20 /* ZFS boot block */
  21 #define VDEV_BOOT_MAGIC         0x2f5b007b10cULL
  22 #define VDEV_BOOT_VERSION       1               /* version number       */
  23
  24 typedef struct vdev_boot_header {
  25         uint64_t        vb_magic;               /* VDEV_BOOT_MAGIC      */
  26         uint64_t        vb_version;             /* VDEV_BOOT_VERSION    */
  27         uint64_t        vb_offset;              /* start offset (bytes) */
  28         uint64_t        vb_size;                /* size (bytes)         */
  29         char            vb_pad[VDEV_BOOT_HEADER_SIZE - 4 * sizeof(uint64_t)];
  30 } vdev_boot_header_t;
  31
  32 typedef struct vdev_phys {
  33         char            vp_nvlist[VDEV_PHYS_SIZE - sizeof(zio_eck_t)];
  34         zio_eck_t       vp_zbt;
  35 } vdev_phys_t;
  36
  37 typedef struct vdev_label {
  38         char            vl_pad[VDEV_SKIP_SIZE];                 /*   8K */
  39         vdev_boot_header_t vl_boot_header;                      /*   8K */
  40         vdev_phys_t     vl_vdev_phys;                           /* 112K */
  41         char            vl_uberblock[VDEV_UBERBLOCK_RING];      /* 128K */
  42 } vdev_label_t;                                                 /* 256K total */
  43
  44 /*
  45  * Size and offset of embedded boot loader region on each label.
  46  * The total size of the first two labels plus the boot area is 4MB.
  47  */
  48 #define VDEV_BOOT_OFFSET        (2 * sizeof(vdev_label_t))
  49 #define VDEV_BOOT_SIZE          (7ULL << 19)                    /* 3.5M */
  50
  51 /*
  52  * Size of label regions at the start and end of each leaf device.
  53  */
  54 #define VDEV_LABEL_START_SIZE   (2 * sizeof(vdev_label_t) + VDEV_BOOT_SIZE)
  55 #define VDEV_LABEL_END_SIZE     (2 * sizeof(vdev_label_t))
  56 #define VDEV_LABELS             4
  57
  58 #endif  /* _SYS_VDEV_IMPL_H */