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 __LINUX_UBI_H__ 22 #define __LINUX_UBI_H__ 23 24 #include <asm/ioctl.h> 25 #include <linux/types.h> 26 #include <mtd/ubi-user.h> 27 28 /* 29 * UBI data type hint constants. 30 * 31 * UBI_LONGTERM: long-term data 32 * UBI_SHORTTERM: short-term data 33 * UBI_UNKNOWN: data persistence is unknown 34 * 35 * These constants are used when data is written to UBI volumes in order to 36 * help the UBI wear-leveling unit to find more appropriate physical 37 * eraseblocks. 38 */ 39 enum { 40 UBI_LONGTERM = 1, 41 UBI_SHORTTERM, 42 UBI_UNKNOWN 43 }; 44 45 /* 46 * enum ubi_open_mode - UBI volume open mode constants. 47 * 48 * UBI_READONLY: read-only mode 49 * UBI_READWRITE: read-write mode 50 * UBI_EXCLUSIVE: exclusive mode 51 */ 52 enum { 53 UBI_READONLY = 1, 54 UBI_READWRITE, 55 UBI_EXCLUSIVE 56 }; 57 58 /** 59 * struct ubi_volume_info - UBI volume description data structure. 60 * @vol_id: volume ID 61 * @ubi_num: UBI device number this volume belongs to 62 * @size: how many physical eraseblocks are reserved for this volume 63 * @used_bytes: how many bytes of data this volume contains 64 * @used_ebs: how many physical eraseblocks of this volume actually contain any 65 * data 66 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME) 67 * @corrupted: non-zero if the volume is corrupted (static volumes only) 68 * @upd_marker: non-zero if the volume has update marker set 69 * @alignment: volume alignment 70 * @usable_leb_size: how many bytes are available in logical eraseblocks of 71 * this volume 72 * @name_len: volume name length 73 * @name: volume name 74 * @cdev: UBI volume character device major and minor numbers 75 * 76 * The @corrupted flag is only relevant to static volumes and is always zero 77 * for dynamic ones. This is because UBI does not care about dynamic volume 78 * data protection and only cares about protecting static volume data. 79 * 80 * The @upd_marker flag is set if the volume update operation was interrupted. 81 * Before touching the volume data during the update operation, UBI first sets 82 * the update marker flag for this volume. If the volume update operation was 83 * further interrupted, the update marker indicates this. If the update marker 84 * is set, the contents of the volume is certainly damaged and a new volume 85 * update operation has to be started. 86 * 87 * To put it differently, @corrupted and @upd_marker fields have different 88 * semantics: 89 * o the @corrupted flag means that this static volume is corrupted for some 90 * reasons, but not because an interrupted volume update 91 * o the @upd_marker field means that the volume is damaged because of an 92 * interrupted update operation. 93 * 94 * I.e., the @corrupted flag is never set if the @upd_marker flag is set. 95 * 96 * The @used_bytes and @used_ebs fields are only really needed for static 97 * volumes and contain the number of bytes stored in this static volume and how 98 * many eraseblock this data occupies. In case of dynamic volumes, the 99 * @used_bytes field is equivalent to @size*@usable_leb_size, and the @used_ebs 100 * field is equivalent to @size. 101 * 102 * In general, logical eraseblock size is a property of the UBI device, not 103 * of the UBI volume. Indeed, the logical eraseblock size depends on the 104 * physical eraseblock size and on how much bytes UBI headers consume. But 105 * because of the volume alignment (@alignment), the usable size of logical 106 * eraseblocks if a volume may be less. The following equation is true: 107 * @usable_leb_size = LEB size - (LEB size mod @alignment), 108 * where LEB size is the logical eraseblock size defined by the UBI device. 109 * 110 * The alignment is multiple to the minimal flash input/output unit size or %1 111 * if all the available space is used. 112 * 113 * To put this differently, alignment may be considered is a way to change 114 * volume logical eraseblock sizes. 115 */ 116 struct ubi_volume_info { 117 int ubi_num; 118 int vol_id; 119 int size; 120 long long used_bytes; 121 int used_ebs; 122 int vol_type; 123 int corrupted; 124 int upd_marker; 125 int alignment; 126 int usable_leb_size; 127 int name_len; 128 const char *name; 129 dev_t cdev; 130 }; 131 132 /** 133 * struct ubi_device_info - UBI device description data structure. 134 * @ubi_num: ubi device number 135 * @leb_size: logical eraseblock size on this UBI device 136 * @min_io_size: minimal I/O unit size 137 * @ro_mode: if this device is in read-only mode 138 * @cdev: UBI character device major and minor numbers 139 * 140 * Note, @leb_size is the logical eraseblock size offered by the UBI device. 141 * Volumes of this UBI device may have smaller logical eraseblock size if their 142 * alignment is not equivalent to %1. 143 */ 144 struct ubi_device_info { 145 int ubi_num; 146 int leb_size; 147 int min_io_size; 148 int ro_mode; 149 dev_t cdev; 150 }; 151 152 /* UBI descriptor given to users when they open UBI volumes */ 153 struct ubi_volume_desc; 154 155 int ubi_get_device_info(int ubi_num, struct ubi_device_info *di); 156 void ubi_get_volume_info(struct ubi_volume_desc *desc, 157 struct ubi_volume_info *vi); 158 struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode); 159 struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, 160 int mode); 161 void ubi_close_volume(struct ubi_volume_desc *desc); 162 int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, 163 int len, int check); 164 int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, 165 int offset, int len, int dtype); 166 int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, 167 int len, int dtype); 168 int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum); 169 int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum); 170 int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum); 171 172 /* 173 * This function is the same as the 'ubi_leb_read()' function, but it does not 174 * provide the checking capability. 175 */ 176 static inline int ubi_read(struct ubi_volume_desc *desc, int lnum, char *buf, 177 int offset, int len) 178 { 179 return ubi_leb_read(desc, lnum, buf, offset, len, 0); 180 } 181 182 /* 183 * This function is the same as the 'ubi_leb_write()' functions, but it does 184 * not have the data type argument. 185 */ 186 static inline int ubi_write(struct ubi_volume_desc *desc, int lnum, 187 const void *buf, int offset, int len) 188 { 189 return ubi_leb_write(desc, lnum, buf, offset, len, UBI_UNKNOWN); 190 } 191 192 /* 193 * This function is the same as the 'ubi_leb_change()' functions, but it does 194 * not have the data type argument. 195 */ 196 static inline int ubi_change(struct ubi_volume_desc *desc, int lnum, 197 const void *buf, int len) 198 { 199 return ubi_leb_change(desc, lnum, buf, len, UBI_UNKNOWN); 200 } 201 202 #endif /* !__LINUX_UBI_H__ */ 203