1 /* 2 * Copyright (c) International Business Machines Corp., 2006 3 * 4 * SPDX-License-Identifier: GPL-2.0+ 5 * 6 * Author: Artem Bityutskiy (Битюцкий Артём) 7 */ 8 9 #ifndef __LINUX_UBI_H__ 10 #define __LINUX_UBI_H__ 11 12 /* #include <asm/ioctl.h> */ 13 #include <linux/types.h> 14 #include <mtd/ubi-user.h> 15 16 /* 17 * enum ubi_open_mode - UBI volume open mode constants. 18 * 19 * UBI_READONLY: read-only mode 20 * UBI_READWRITE: read-write mode 21 * UBI_EXCLUSIVE: exclusive mode 22 */ 23 enum { 24 UBI_READONLY = 1, 25 UBI_READWRITE, 26 UBI_EXCLUSIVE 27 }; 28 29 /** 30 * struct ubi_volume_info - UBI volume description data structure. 31 * @vol_id: volume ID 32 * @ubi_num: UBI device number this volume belongs to 33 * @size: how many physical eraseblocks are reserved for this volume 34 * @used_bytes: how many bytes of data this volume contains 35 * @used_ebs: how many physical eraseblocks of this volume actually contain any 36 * data 37 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME) 38 * @corrupted: non-zero if the volume is corrupted (static volumes only) 39 * @upd_marker: non-zero if the volume has update marker set 40 * @alignment: volume alignment 41 * @usable_leb_size: how many bytes are available in logical eraseblocks of 42 * this volume 43 * @name_len: volume name length 44 * @name: volume name 45 * @cdev: UBI volume character device major and minor numbers 46 * 47 * The @corrupted flag is only relevant to static volumes and is always zero 48 * for dynamic ones. This is because UBI does not care about dynamic volume 49 * data protection and only cares about protecting static volume data. 50 * 51 * The @upd_marker flag is set if the volume update operation was interrupted. 52 * Before touching the volume data during the update operation, UBI first sets 53 * the update marker flag for this volume. If the volume update operation was 54 * further interrupted, the update marker indicates this. If the update marker 55 * is set, the contents of the volume is certainly damaged and a new volume 56 * update operation has to be started. 57 * 58 * To put it differently, @corrupted and @upd_marker fields have different 59 * semantics: 60 * o the @corrupted flag means that this static volume is corrupted for some 61 * reasons, but not because an interrupted volume update 62 * o the @upd_marker field means that the volume is damaged because of an 63 * interrupted update operation. 64 * 65 * I.e., the @corrupted flag is never set if the @upd_marker flag is set. 66 * 67 * The @used_bytes and @used_ebs fields are only really needed for static 68 * volumes and contain the number of bytes stored in this static volume and how 69 * many eraseblock this data occupies. In case of dynamic volumes, the 70 * @used_bytes field is equivalent to @size*@usable_leb_size, and the @used_ebs 71 * field is equivalent to @size. 72 * 73 * In general, logical eraseblock size is a property of the UBI device, not 74 * of the UBI volume. Indeed, the logical eraseblock size depends on the 75 * physical eraseblock size and on how much bytes UBI headers consume. But 76 * because of the volume alignment (@alignment), the usable size of logical 77 * eraseblocks if a volume may be less. The following equation is true: 78 * @usable_leb_size = LEB size - (LEB size mod @alignment), 79 * where LEB size is the logical eraseblock size defined by the UBI device. 80 * 81 * The alignment is multiple to the minimal flash input/output unit size or %1 82 * if all the available space is used. 83 * 84 * To put this differently, alignment may be considered is a way to change 85 * volume logical eraseblock sizes. 86 */ 87 struct ubi_volume_info { 88 int ubi_num; 89 int vol_id; 90 int size; 91 long long used_bytes; 92 int used_ebs; 93 int vol_type; 94 int corrupted; 95 int upd_marker; 96 int alignment; 97 int usable_leb_size; 98 int name_len; 99 const char *name; 100 dev_t cdev; 101 }; 102 103 /** 104 * struct ubi_device_info - UBI device description data structure. 105 * @ubi_num: ubi device number 106 * @leb_size: logical eraseblock size on this UBI device 107 * @min_io_size: minimal I/O unit size 108 * @ro_mode: if this device is in read-only mode 109 * @cdev: UBI character device major and minor numbers 110 * 111 * Note, @leb_size is the logical eraseblock size offered by the UBI device. 112 * Volumes of this UBI device may have smaller logical eraseblock size if their 113 * alignment is not equivalent to %1. 114 */ 115 struct ubi_device_info { 116 int ubi_num; 117 int leb_size; 118 int min_io_size; 119 int ro_mode; 120 dev_t cdev; 121 }; 122 123 /* UBI descriptor given to users when they open UBI volumes */ 124 struct ubi_volume_desc; 125 126 int ubi_get_device_info(int ubi_num, struct ubi_device_info *di); 127 void ubi_get_volume_info(struct ubi_volume_desc *desc, 128 struct ubi_volume_info *vi); 129 struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode); 130 struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, 131 int mode); 132 void ubi_close_volume(struct ubi_volume_desc *desc); 133 int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, 134 int len, int check); 135 int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, 136 int offset, int len, int dtype); 137 int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, 138 int len, int dtype); 139 int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum); 140 int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum); 141 int ubi_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype); 142 int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum); 143 144 /* 145 * This function is the same as the 'ubi_leb_read()' function, but it does not 146 * provide the checking capability. 147 */ 148 static inline int ubi_read(struct ubi_volume_desc *desc, int lnum, char *buf, 149 int offset, int len) 150 { 151 return ubi_leb_read(desc, lnum, buf, offset, len, 0); 152 } 153 154 /* 155 * This function is the same as the 'ubi_leb_write()' functions, but it does 156 * not have the data type argument. 157 */ 158 static inline int ubi_write(struct ubi_volume_desc *desc, int lnum, 159 const void *buf, int offset, int len) 160 { 161 return ubi_leb_write(desc, lnum, buf, offset, len, UBI_UNKNOWN); 162 } 163 164 /* 165 * This function is the same as the 'ubi_leb_change()' functions, but it does 166 * not have the data type argument. 167 */ 168 static inline int ubi_change(struct ubi_volume_desc *desc, int lnum, 169 const void *buf, int len) 170 { 171 return ubi_leb_change(desc, lnum, buf, len, UBI_UNKNOWN); 172 } 173 174 #endif /* !__LINUX_UBI_H__ */ 175