drivers/mtd/ubi/scan.h

   1 /*
   2  * Copyright (c) International Business Machines Corp., 2006
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
  12  * the GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  17  *
  18  * Author: Artem Bityutskiy (Битюцкий Артём)
  19  */
  20
  21 #ifndef __UBI_SCAN_H__
  22 #define __UBI_SCAN_H__
  23
  24 /* The erase counter value for this physical eraseblock is unknown */
  25 #define UBI_SCAN_UNKNOWN_EC (-1)
  26
  27 /**
  28  * struct ubi_scan_leb - scanning information about a physical eraseblock.
  29  * @ec: erase counter (%UBI_SCAN_UNKNOWN_EC if it is unknown)
  30  * @pnum: physical eraseblock number
  31  * @lnum: logical eraseblock number
  32  * @scrub: if this physical eraseblock needs scrubbing
  33  * @copy_flag: this LEB is a copy (@copy_flag is set in VID header of this LEB)
  34  * @sqnum: sequence number
  35  * @u: unions RB-tree or @list links
  36  * @u.rb: link in the per-volume RB-tree of &struct ubi_scan_leb objects
  37  * @u.list: link in one of the eraseblock lists
  38  *
  39  * One object of this type is allocated for each physical eraseblock during
  40  * scanning.
  41  */
  42 struct ubi_scan_leb {
  43         int ec;
  44         int pnum;
  45         int lnum;
  46         unsigned int scrub:1;
  47         unsigned int copy_flag:1;
  48         unsigned long long sqnum;
  49         union {
  50                 struct rb_node rb;
  51                 struct list_head list;
  52         } u;
  53 };
  54
  55 /**
  56  * struct ubi_scan_volume - scanning information about a volume.
  57  * @vol_id: volume ID
  58  * @highest_lnum: highest logical eraseblock number in this volume
  59  * @leb_count: number of logical eraseblocks in this volume
  60  * @vol_type: volume type
  61  * @used_ebs: number of used logical eraseblocks in this volume (only for
  62  *            static volumes)
  63  * @last_data_size: amount of data in the last logical eraseblock of this
  64  *                  volume (always equivalent to the usable logical eraseblock
  65  *                  size in case of dynamic volumes)
  66  * @data_pad: how many bytes at the end of logical eraseblocks of this volume
  67  *            are not used (due to volume alignment)
  68  * @compat: compatibility flags of this volume
  69  * @rb: link in the volume RB-tree
  70  * @root: root of the RB-tree containing all the eraseblock belonging to this
  71  *        volume (&struct ubi_scan_leb objects)
  72  *
  73  * One object of this type is allocated for each volume during scanning.
  74  */
  75 struct ubi_scan_volume {
  76         int vol_id;
  77         int highest_lnum;
  78         int leb_count;
  79         int vol_type;
  80         int used_ebs;
  81         int last_data_size;
  82         int data_pad;
  83         int compat;
  84         struct rb_node rb;
  85         struct rb_root root;
  86 };
  87
  88 /**
  89  * struct ubi_scan_info - UBI scanning information.
  90  * @volumes: root of the volume RB-tree
  91  * @corr: list of corrupted physical eraseblocks
  92  * @free: list of free physical eraseblocks
  93  * @erase: list of physical eraseblocks which have to be erased
  94  * @alien: list of physical eraseblocks which should not be used by UBI (e.g.,
  95  *         those belonging to "preserve"-compatible internal volumes)
  96  * @corr_peb_count: count of PEBs in the @corr list
  97  * @empty_peb_count: count of PEBs which are presumably empty (contain only
  98  *                   0xFF bytes)
  99  * @alien_peb_count: count of PEBs in the @alien list
 100  * @bad_peb_count: count of bad physical eraseblocks
 101  * @maybe_bad_peb_count: count of bad physical eraseblocks which are not marked
 102  *                       as bad yet, but which look like bad
 103  * @vols_found: number of volumes found during scanning
 104  * @highest_vol_id: highest volume ID
 105  * @is_empty: flag indicating whether the MTD device is empty or not
 106  * @min_ec: lowest erase counter value
 107  * @max_ec: highest erase counter value
 108  * @max_sqnum: highest sequence number value
 109  * @mean_ec: mean erase counter value
 110  * @ec_sum: a temporary variable used when calculating @mean_ec
 111  * @ec_count: a temporary variable used when calculating @mean_ec
 112  * @scan_leb_slab: slab cache for &struct ubi_scan_leb objects
 113  *
 114  * This data structure contains the result of scanning and may be used by other
 115  * UBI sub-systems to build final UBI data structures, further error-recovery
 116  * and so on.
 117  */
 118 struct ubi_scan_info {
 119         struct rb_root volumes;
 120         struct list_head corr;
 121         struct list_head free;
 122         struct list_head erase;
 123         struct list_head alien;
 124         int corr_peb_count;
 125         int empty_peb_count;
 126         int alien_peb_count;
 127         int bad_peb_count;
 128         int maybe_bad_peb_count;
 129         int vols_found;
 130         int highest_vol_id;
 131         int is_empty;
 132         int min_ec;
 133         int max_ec;
 134         unsigned long long max_sqnum;
 135         int mean_ec;
 136         uint64_t ec_sum;
 137         int ec_count;
 138         struct kmem_cache *scan_leb_slab;
 139 };
 140
 141 struct ubi_device;
 142 struct ubi_vid_hdr;
 143
 144 /*
 145  * ubi_scan_move_to_list - move a PEB from the volume tree to a list.
 146  *
 147  * @sv: volume scanning information
 148  * @seb: scanning eraseblock information
 149  * @list: the list to move to
 150  */
 151 static inline void ubi_scan_move_to_list(struct ubi_scan_volume *sv,
 152                                          struct ubi_scan_leb *seb,
 153                                          struct list_head *list)
 154 {
 155                 rb_erase(&seb->u.rb, &sv->root);
 156                 list_add_tail(&seb->u.list, list);
 157 }
 158
 159 int ubi_scan_add_used(struct ubi_device *ubi, struct ubi_scan_info *si,
 160                       int pnum, int ec, const struct ubi_vid_hdr *vid_hdr,
 161                       int bitflips);
 162 struct ubi_scan_volume *ubi_scan_find_sv(const struct ubi_scan_info *si,
 163                                          int vol_id);
 164 struct ubi_scan_leb *ubi_scan_find_seb(const struct ubi_scan_volume *sv,
 165                                        int lnum);
 166 void ubi_scan_rm_volume(struct ubi_scan_info *si, struct ubi_scan_volume *sv);
 167 struct ubi_scan_leb *ubi_scan_get_free_peb(struct ubi_device *ubi,
 168                                            struct ubi_scan_info *si);
 169 int ubi_scan_erase_peb(struct ubi_device *ubi, const struct ubi_scan_info *si,
 170                        int pnum, int ec);
 171 struct ubi_scan_info *ubi_scan(struct ubi_device *ubi);
 172 void ubi_scan_destroy_si(struct ubi_scan_info *si);
 173
 174 #endif /* !__UBI_SCAN_H__ */