Initial import

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diff --git a/include/linux/mtd/ubi.h b/include/linux/mtd/ubi.h
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+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+#ifndef __LINUX_UBI_H__
+#define __LINUX_UBI_H__
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+#include <linux/scatterlist.h>
+#include <mtd/ubi-user.h>
+
+/* All voumes/LEBs */
+#define UBI_ALL -1
+
+/*
+ * Maximum number of scatter gather list entries,
+ * we use only 64 to have a lower memory foot print.
+ */
+#define UBI_MAX_SG_COUNT 64
+
+/*
+ * enum ubi_open_mode - UBI volume open mode constants.
+ *
+ * UBI_READONLY: read-only mode
+ * UBI_READWRITE: read-write mode
+ * UBI_EXCLUSIVE: exclusive mode
+ * UBI_METAONLY: modify only the volume meta-data,
+ *  i.e. the data stored in the volume table, but not in any of volume LEBs.
+ */
+enum {
+	UBI_READONLY = 1,
+	UBI_READWRITE,
+	UBI_EXCLUSIVE,
+	UBI_METAONLY
+};
+
+/**
+ * struct ubi_volume_info - UBI volume description data structure.
+ * @vol_id: volume ID
+ * @ubi_num: UBI device number this volume belongs to
+ * @size: how many physical eraseblocks are reserved for this volume
+ * @used_bytes: how many bytes of data this volume contains
+ * @used_ebs: how many physical eraseblocks of this volume actually contain any
+ *            data
+ * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
+ * @corrupted: non-zero if the volume is corrupted (static volumes only)
+ * @upd_marker: non-zero if the volume has update marker set
+ * @alignment: volume alignment
+ * @usable_leb_size: how many bytes are available in logical eraseblocks of
+ *                   this volume
+ * @name_len: volume name length
+ * @name: volume name
+ * @cdev: UBI volume character device major and minor numbers
+ *
+ * The @corrupted flag is only relevant to static volumes and is always zero
+ * for dynamic ones. This is because UBI does not care about dynamic volume
+ * data protection and only cares about protecting static volume data.
+ *
+ * The @upd_marker flag is set if the volume update operation was interrupted.
+ * Before touching the volume data during the update operation, UBI first sets
+ * the update marker flag for this volume. If the volume update operation was
+ * further interrupted, the update marker indicates this. If the update marker
+ * is set, the contents of the volume is certainly damaged and a new volume
+ * update operation has to be started.
+ *
+ * To put it differently, @corrupted and @upd_marker fields have different
+ * semantics:
+ *     o the @corrupted flag means that this static volume is corrupted for some
+ *       reasons, but not because an interrupted volume update
+ *     o the @upd_marker field means that the volume is damaged because of an
+ *       interrupted update operation.
+ *
+ * I.e., the @corrupted flag is never set if the @upd_marker flag is set.
+ *
+ * The @used_bytes and @used_ebs fields are only really needed for static
+ * volumes and contain the number of bytes stored in this static volume and how
+ * many eraseblock this data occupies. In case of dynamic volumes, the
+ * @used_bytes field is equivalent to @size*@usable_leb_size, and the @used_ebs
+ * field is equivalent to @size.
+ *
+ * In general, logical eraseblock size is a property of the UBI device, not
+ * of the UBI volume. Indeed, the logical eraseblock size depends on the
+ * physical eraseblock size and on how much bytes UBI headers consume. But
+ * because of the volume alignment (@alignment), the usable size of logical
+ * eraseblocks if a volume may be less. The following equation is true:
+ *	@usable_leb_size = LEB size - (LEB size mod @alignment),
+ * where LEB size is the logical eraseblock size defined by the UBI device.
+ *
+ * The alignment is multiple to the minimal flash input/output unit size or %1
+ * if all the available space is used.
+ *
+ * To put this differently, alignment may be considered is a way to change
+ * volume logical eraseblock sizes.
+ */
+struct ubi_volume_info {
+	int ubi_num;
+	int vol_id;
+	int size;
+	long long used_bytes;
+	int used_ebs;
+	int vol_type;
+	int corrupted;
+	int upd_marker;
+	int alignment;
+	int usable_leb_size;
+	int name_len;
+	const char *name;
+	dev_t cdev;
+};
+
+/**
+ * struct ubi_sgl - UBI scatter gather list data structure.
+ * @list_pos: current position in @sg[]
+ * @page_pos: current position in @sg[@list_pos]
+ * @sg: the scatter gather list itself
+ *
+ * ubi_sgl is a wrapper around a scatter list which keeps track of the
+ * current position in the list and the current list item such that
+ * it can be used across multiple ubi_leb_read_sg() calls.
+ */
+struct ubi_sgl {
+	int list_pos;
+	int page_pos;
+	struct scatterlist sg[UBI_MAX_SG_COUNT];
+};
+
+/**
+ * ubi_sgl_init - initialize an UBI scatter gather list data structure.
+ * @usgl: the UBI scatter gather struct itself
+ *
+ * Please note that you still have to use sg_init_table() or any adequate
+ * function to initialize the unterlaying struct scatterlist.
+ */
+static inline void ubi_sgl_init(struct ubi_sgl *usgl)
+{
+	usgl->list_pos = 0;
+	usgl->page_pos = 0;
+}
+
+/**
+ * struct ubi_device_info - UBI device description data structure.
+ * @ubi_num: ubi device number
+ * @leb_size: logical eraseblock size on this UBI device
+ * @leb_start: starting offset of logical eraseblocks within physical
+ *             eraseblocks
+ * @min_io_size: minimal I/O unit size
+ * @max_write_size: maximum amount of bytes the underlying flash can write at a
+ *                  time (MTD write buffer size)
+ * @ro_mode: if this device is in read-only mode
+ * @cdev: UBI character device major and minor numbers
+ *
+ * Note, @leb_size is the logical eraseblock size offered by the UBI device.
+ * Volumes of this UBI device may have smaller logical eraseblock size if their
+ * alignment is not equivalent to %1.
+ *
+ * The @max_write_size field describes flash write maximum write unit. For
+ * example, NOR flash allows for changing individual bytes, so @min_io_size is
+ * %1. However, it does not mean than NOR flash has to write data byte-by-byte.
+ * Instead, CFI NOR flashes have a write-buffer of, e.g., 64 bytes, and when
+ * writing large chunks of data, they write 64-bytes at a time. Obviously, this
+ * improves write throughput.
+ *
+ * Also, the MTD device may have N interleaved (striped) flash chips
+ * underneath, in which case @min_io_size can be physical min. I/O size of
+ * single flash chip, while @max_write_size can be N * @min_io_size.
+ *
+ * The @max_write_size field is always greater or equivalent to @min_io_size.
+ * E.g., some NOR flashes may have (@min_io_size = 1, @max_write_size = 64). In
+ * contrast, NAND flashes usually have @min_io_size = @max_write_size = NAND
+ * page size.
+ */
+struct ubi_device_info {
+	int ubi_num;
+	int leb_size;
+	int leb_start;
+	int min_io_size;
+	int max_write_size;
+	int ro_mode;
+	dev_t cdev;
+};
+
+/*
+ * Volume notification types.
+ * @UBI_VOLUME_ADDED: a volume has been added (an UBI device was attached or a
+ *                    volume was created)
+ * @UBI_VOLUME_REMOVED: a volume has been removed (an UBI device was detached
+ *			or a volume was removed)
+ * @UBI_VOLUME_RESIZED: a volume has been re-sized
+ * @UBI_VOLUME_RENAMED: a volume has been re-named
+ * @UBI_VOLUME_UPDATED: data has been written to a volume
+ *
+ * These constants define which type of event has happened when a volume
+ * notification function is invoked.
+ */
+enum {
+	UBI_VOLUME_ADDED,
+	UBI_VOLUME_REMOVED,
+	UBI_VOLUME_RESIZED,
+	UBI_VOLUME_RENAMED,
+	UBI_VOLUME_UPDATED,
+};
+
+/*
+ * struct ubi_notification - UBI notification description structure.
+ * @di: UBI device description object
+ * @vi: UBI volume description object
+ *
+ * UBI notifiers are called with a pointer to an object of this type. The
+ * object describes the notification. Namely, it provides a description of the
+ * UBI device and UBI volume the notification informs about.
+ */
+struct ubi_notification {
+	struct ubi_device_info di;
+	struct ubi_volume_info vi;
+};
+
+/* UBI descriptor given to users when they open UBI volumes */
+struct ubi_volume_desc;
+
+int ubi_get_device_info(int ubi_num, struct ubi_device_info *di);
+void ubi_get_volume_info(struct ubi_volume_desc *desc,
+			 struct ubi_volume_info *vi);
+struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode);
+struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name,
+					   int mode);
+struct ubi_volume_desc *ubi_open_volume_path(const char *pathname, int mode);
+
+int ubi_register_volume_notifier(struct notifier_block *nb,
+				 int ignore_existing);
+int ubi_unregister_volume_notifier(struct notifier_block *nb);
+
+void ubi_close_volume(struct ubi_volume_desc *desc);
+int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset,
+		 int len, int check);
+int ubi_leb_read_sg(struct ubi_volume_desc *desc, int lnum, struct ubi_sgl *sgl,
+		   int offset, int len, int check);
+int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,
+		  int offset, int len);
+int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,
+		   int len);
+int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum);
+int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum);
+int ubi_leb_map(struct ubi_volume_desc *desc, int lnum);
+int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum);
+int ubi_sync(int ubi_num);
+int ubi_flush(int ubi_num, int vol_id, int lnum);
+
+/*
+ * This function is the same as the 'ubi_leb_read()' function, but it does not
+ * provide the checking capability.
+ */
+static inline int ubi_read(struct ubi_volume_desc *desc, int lnum, char *buf,
+			   int offset, int len)
+{
+	return ubi_leb_read(desc, lnum, buf, offset, len, 0);
+}
+
+/*
+ * This function is the same as the 'ubi_leb_read_sg()' function, but it does
+ * not provide the checking capability.
+ */
+static inline int ubi_read_sg(struct ubi_volume_desc *desc, int lnum,
+			      struct ubi_sgl *sgl, int offset, int len)
+{
+	return ubi_leb_read_sg(desc, lnum, sgl, offset, len, 0);
+}
+#endif /* !__LINUX_UBI_H__ */