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 */
 42struct 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 */
 75struct 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 */
118struct 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
141struct ubi_device;
142struct 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 */
151static 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
159int 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);
162struct ubi_scan_volume *ubi_scan_find_sv(const struct ubi_scan_info *si,
163					 int vol_id);
164struct ubi_scan_leb *ubi_scan_find_seb(const struct ubi_scan_volume *sv,
165				       int lnum);
166void ubi_scan_rm_volume(struct ubi_scan_info *si, struct ubi_scan_volume *sv);
167struct ubi_scan_leb *ubi_scan_get_free_peb(struct ubi_device *ubi,
168					   struct ubi_scan_info *si);
169int ubi_scan_erase_peb(struct ubi_device *ubi, const struct ubi_scan_info *si,
170		       int pnum, int ec);
171struct ubi_scan_info *ubi_scan(struct ubi_device *ubi);
172void ubi_scan_destroy_si(struct ubi_scan_info *si);
173
174#endif /* !__UBI_SCAN_H__ */