include/linux/raid/raid1.h

   1 #ifndef _RAID1_H
   2 #define _RAID1_H
   3
   4 #include <linux/raid/md.h>
   5
   6 typedef struct mirror_info mirror_info_t;
   7
   8 struct mirror_info {
   9         mdk_rdev_t      *rdev;
  10         sector_t        head_position;
  11 };
  12
  13 /*
  14  * memory pools need a pointer to the mddev, so they can force an unplug
  15  * when memory is tight, and a count of the number of drives that the
  16  * pool was allocated for, so they know how much to allocate and free.
  17  * mddev->raid_disks cannot be used, as it can change while a pool is active
  18  * These two datums are stored in a kmalloced struct.
  19  */
  20
  21 struct pool_info {
  22         mddev_t *mddev;
  23         int     raid_disks;
  24 };
  25
  26
  27 typedef struct r1bio_s r1bio_t;
  28
  29 struct r1_private_data_s {
  30         mddev_t                 *mddev;
  31         mirror_info_t           *mirrors;
  32         int                     raid_disks;
  33         int                     working_disks;
  34         int                     last_used;
  35         sector_t                next_seq_sect;
  36         spinlock_t              device_lock;
  37
  38         struct list_head        retry_list;
  39         /* for use when syncing mirrors: */
  40
  41         spinlock_t              resync_lock;
  42         int nr_pending;
  43         int barrier;
  44         sector_t                next_resync;
  45
  46         wait_queue_head_t       wait_idle;
  47         wait_queue_head_t       wait_resume;
  48
  49         struct pool_info        *poolinfo;
  50
  51         mempool_t *r1bio_pool;
  52         mempool_t *r1buf_pool;
  53 };
  54
  55 typedef struct r1_private_data_s conf_t;
  56
  57 /*
  58  * this is the only point in the RAID code where we violate
  59  * C type safety. mddev->private is an 'opaque' pointer.
  60  */
  61 #define mddev_to_conf(mddev) ((conf_t *) mddev->private)
  62
  63 /*
  64  * this is our 'private' RAID1 bio.
  65  *
  66  * it contains information about what kind of IO operations were started
  67  * for this RAID1 operation, and about their status:
  68  */
  69
  70 struct r1bio_s {
  71         atomic_t                remaining; /* 'have we finished' count,
  72                                             * used from IRQ handlers
  73                                             */
  74         sector_t                sector;
  75         int                     sectors;
  76         unsigned long           state;
  77         mddev_t                 *mddev;
  78         /*
  79          * original bio going to /dev/mdx
  80          */
  81         struct bio              *master_bio;
  82         /*
  83          * if the IO is in READ direction, then this is where we read
  84          */
  85         int                     read_disk;
  86
  87         struct list_head        retry_list;
  88         /*
  89          * if the IO is in WRITE direction, then multiple bios are used.
  90          * We choose the number when they are allocated.
  91          */
  92         struct bio              *bios[0];
  93 };
  94
  95 /* bits for r1bio.state */
  96 #define R1BIO_Uptodate  0
  97 #define R1BIO_IsSync    1
  98 #endif