ubi-utils: add libmtd

Just collection of functions to make it easier to work with MTD devices.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

diff --git a/ubi-utils/new-utils/include/libmtd.h b/ubi-utils/new-utils/include/libmtd.h
new file mode 100644 (file)
index 0000000..d3c6a63
--- /dev/null
+++ b/ubi-utils/new-utils/include/libmtd.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Author: Artem Bityutskiy
+ *
+ * MTD library.
+ */
+
+#ifndef __LIBMTD_H__
+#define __LIBMTD_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * struct mtd_info - information about an MTD device.
+ * @num: MTD device number
+ * @major: major number of corresponding character device
+ * @minor: minor number of corresponding character device
+ * @type: flash type (constants like %MTD_NANDFLASH defined in mtd-abi.h)
+ * @type_str: static R/O flash type string
+ * @size: device size in bytes
+ * @eb_cnt: count of eraseblocks
+ * @eb_size: eraseblock size
+ * @min_io_size: minimum input/output unit size
+ * @subpage_size: sub-page size (not set by 'mtd_get_info()'!!!)
+ * @rdonly: non-zero if the device is read-only
+ * @allows_bb: non-zero if the MTD device may have bad eraseblocks
+ * @fd: descriptor of the opened MTD character device node
+ */
+struct mtd_info
+{
+       int num;
+       int major;
+       int minor;
+       int type;
+       const char *type_str;
+       long long size;
+       int eb_cnt;
+       int eb_size;
+       int min_io_size;
+       int subpage_size;
+       unsigned int rdonly:1;
+       unsigned int allows_bb:1;
+       int fd;
+};
+
+int mtd_get_info(const char *node, struct mtd_info *mtd);
+int mtd_erase(const struct mtd_info *mtd, int eb);
+int mtd_is_bad(const struct mtd_info *mtd, int eb);
+int mtd_read(const struct mtd_info *mtd, int eb, int offs, void *buf, int len);
+int mtd_write(const struct mtd_info *mtd, int eb, int offs, void *buf, int len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LIBMTD_H__ */

diff --git a/ubi-utils/new-utils/src/libmtd.c b/ubi-utils/new-utils/src/libmtd.c
new file mode 100644 (file)
index 0000000..aab4b0e
--- /dev/null
+++ b/ubi-utils/new-utils/src/libmtd.c
@@ -0,0 +1,314 @@
+/*
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Author: Artem Bityutskiy
+ *
+ * MTD library.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include <mtd/mtd-user.h>
+#include <libmtd.h>
+#include "common.h"
+
+#define PROGRAM_NAME "libmtd"
+#define MTD_DEV_MAJOR 90
+
+/**
+ * mtd_get_info - get information about an MTD device.
+ * @node: name of the MTD device node
+ * @mtd: the MTD device information is returned here
+ *
+ * This function gets information about MTD device defined by the @node device
+ * node file and saves this information in the @mtd object. Returns %0 in case
+ * of success and %-1 in case of failure.
+ */
+int mtd_get_info(const char *node, struct mtd_info *mtd)
+{
+       struct stat st;
+       struct mtd_info_user ui;
+       int ret;
+       loff_t offs = 0;
+
+       if (stat(node, &st))
+               return sys_errmsg("cannot open \"%s\"", node);
+
+       if (!S_ISCHR(st.st_mode)) {
+               errno = EINVAL;
+               return errmsg("\"%s\" is not a character device", node);
+       }
+
+       mtd->major = major(st.st_rdev);
+       mtd->minor = minor(st.st_rdev);
+
+       if (mtd->major != MTD_DEV_MAJOR) {
+               errno = EINVAL;
+               return errmsg("\"%s\" has major number %d, MTD devices have "
+                             "major %d", node, mtd->major, MTD_DEV_MAJOR);
+       }
+
+       mtd->num = mtd->minor / 2;
+       mtd->rdonly = mtd->minor & 1;
+
+       mtd->fd = open(node, O_RDWR);
+       if (mtd->fd == -1)
+               return sys_errmsg("cannot open \"%s\"", node);
+
+       if (ioctl(mtd->fd, MEMGETINFO, &ui)) {
+               sys_errmsg("MEMGETINFO ioctl request failed");
+               goto out_close;
+       }
+
+       ret = ioctl(mtd->fd, MEMGETBADBLOCK, &offs);
+       if (ret == -1) {
+               if (errno != EOPNOTSUPP) {
+                       sys_errmsg("MEMGETBADBLOCK ioctl failed");
+                       goto out_close;
+               }
+               errno = 0;
+               mtd->allows_bb = 0;
+       } else
+               mtd->allows_bb = 1;
+
+       mtd->type = ui.type;
+       mtd->size = ui.size;
+       mtd->eb_size = ui.erasesize;
+       mtd->min_io_size = ui.writesize;
+
+       if (mtd->min_io_size <= 0) {
+               errmsg("mtd%d (%s) has insane min. I/O unit size %d",
+                      mtd->num, node, mtd->min_io_size);
+               goto out_close;
+       }
+       if (mtd->eb_size <= 0 || mtd->eb_size < mtd->min_io_size) {
+               errmsg("mtd%d (%s) has insane eraseblock size %d",
+                      mtd->num, node, mtd->eb_size);
+               goto out_close;
+       }
+       if (mtd->size <= 0 || mtd->size < mtd->eb_size) {
+               errmsg("mtd%d (%s) has insane size %lld",
+                      mtd->num, node, mtd->size);
+               goto out_close;
+       }
+       mtd->eb_cnt = mtd->size / mtd->eb_size;
+
+       switch(mtd->type) {
+       case MTD_ABSENT:
+               errmsg("mtd%d (%s) is removable and is not present",
+                      mtd->num, node);
+               goto out_close;
+       case MTD_RAM:
+               mtd->type_str = "RAM-based";
+               break;
+       case MTD_ROM:
+               mtd->type_str = "ROM";
+               break;
+       case MTD_NORFLASH:
+               mtd->type_str = "NOR";
+               break;
+       case MTD_NANDFLASH:
+               mtd->type_str = "NAND";
+               break;
+       case MTD_DATAFLASH:
+               mtd->type_str = "DataFlash";
+               break;
+       case MTD_UBIVOLUME:
+               mtd->type_str = "UBI-emulated MTD";
+               break;
+       default:
+               mtd->type_str = "Unknown flash type";
+               break;
+       }
+
+       if (!(ui.flags & MTD_WRITEABLE))
+               mtd->rdonly = 1;
+
+       return 0;
+
+out_close:
+       close(mtd->fd);
+       return -1;
+}
+
+/**
+ * mtd_erase - erase an eraseblock.
+ * @mtd: MTD device description object
+ * @eb: eraseblock to erase
+ *
+ * This function erases the eraseblock and returns %0 in case of success and
+ * %-1 in case of failure.
+ */
+int mtd_erase(const struct mtd_info *mtd, int eb)
+{
+       struct erase_info_user ei;
+
+       ei.start = eb * mtd->eb_size;;
+       ei.length = mtd->eb_size;
+       return ioctl(mtd->fd, MEMERASE, &ei);
+}
+
+/**
+ * mtd_is_bad - check if eraseblock is bad.
+ * @mtd: MTD device description object
+ * @eb: eraseblock to check
+ *
+ * This function checks if eraseblock @eb is bad. Returns %0 if not, %1 if yes,
+ * and %-1 in case of failure.
+ */
+int mtd_is_bad(const struct mtd_info *mtd, int eb)
+{
+       int ret;
+       loff_t seek;
+
+       if (eb < 0 || eb >= mtd->eb_cnt) {
+               errmsg("bad eraseblock number %d, mtd%d has %d eraseblocks",
+                      eb, mtd->num, mtd->eb_cnt);
+               errno = EINVAL;
+               return -1;
+       }
+
+       if (!mtd->allows_bb)
+               return 0;
+
+       seek = eb * mtd->eb_size;
+       ret = ioctl(mtd->fd, MEMGETBADBLOCK, &seek);
+       if (ret == -1) {
+               sys_errmsg("MEMGETBADBLOCK ioctl failed for "
+                          "eraseblock %d (mtd%d)", eb, mtd->num);
+               return -1;
+       }
+
+       return ret;
+}
+
+/**
+ * mtd_read - read data from an MTD device.
+ * @mtd: MTD device description object
+ * @eb: eraseblock to read from
+ * @offs: offset withing the eraseblock to read from
+ * @buf: buffer to read data to
+ * @len: how many bytes to read
+ *
+ * This function reads @len bytes of data from eraseblock @eb and offset @offs
+ * of the MTD device defined by @mtd and stores the read data at buffer @buf.
+ * Returns %0 in case of success and %-1 in case of failure.
+ */
+int mtd_read(const struct mtd_info *mtd, int eb, int offs, void *buf, int len)
+{
+       int ret, rd = 0;
+       off_t seek;
+
+       if (eb < 0 || eb >= mtd->eb_cnt) {
+               errmsg("bad eraseblock number %d, mtd%d has %d eraseblocks",
+                      eb, mtd->num, mtd->eb_cnt);
+               errno = EINVAL;
+               return -1;
+       }
+       if (offs < 0 || offs + len > mtd->eb_size) {
+               errmsg("bad offset %d or length %d, mtd%d eraseblock size is %d",
+                      offs, len, mtd->num, mtd->eb_size);
+               errno = EINVAL;
+               return -1;
+       }
+
+       /* Seek to the beginning of the eraseblock */
+       seek = eb * mtd->eb_size + offs;
+       if (lseek(mtd->fd, seek, SEEK_SET) != seek) {
+               sys_errmsg("cannot seek mtd%d to offset %llu",
+                          mtd->num, (unsigned long long)seek);
+               return -1;
+       }
+
+       while (rd < len) {
+               ret = read(mtd->fd, buf, len);
+               if (ret < 0) {
+                       sys_errmsg("cannot read %d bytes from mtd%d (eraseblock %d, offset %d)",
+                                  len, mtd->num, eb, offs);
+                       return -1;
+               }
+               rd += ret;
+       }
+
+       return 0;
+}
+
+/**
+ * mtd_write - write data to an MTD device.
+ * @mtd: MTD device description object
+ * @eb: eraseblock to write to
+ * @offs: offset withing the eraseblock to write to
+ * @buf: buffer to write
+ * @len: how many bytes to write
+ *
+ * This function writes @len bytes of data to eraseblock @eb and offset @offs
+ * of the MTD device defined by @mtd. Returns %0 in case of success and %-1 in
+ * case of failure.
+ */
+int mtd_write(const struct mtd_info *mtd, int eb, int offs, void *buf, int len)
+{
+       int ret;
+       off_t seek;
+
+       if (eb < 0 || eb >= mtd->eb_cnt) {
+               errmsg("bad eraseblock number %d, mtd%d has %d eraseblocks",
+                      eb, mtd->num, mtd->eb_cnt);
+               errno = EINVAL;
+               return -1;
+       }
+       if (offs < 0 || offs + len > mtd->eb_size) {
+               errmsg("bad offset %d or length %d, mtd%d eraseblock size is %d",
+                      offs, len, mtd->num, mtd->eb_size);
+               errno = EINVAL;
+               return -1;
+       }
+#if 0
+       if (offs % mtd->subpage_size) {
+               errmsg("write offset %d is not aligned to mtd%d min. I/O size %d",
+                      offs, mtd->num, mtd->subpage_size);
+               errno = EINVAL;
+               return -1;
+       }
+       if (len % mtd->subpage_size) {
+               errmsg("write length %d is not aligned to mtd%d min. I/O size %d",
+                      len, mtd->num, mtd->subpage_size);
+               errno = EINVAL;
+               return -1;
+       }
+#endif
+
+       /* Seek to the beginning of the eraseblock */
+       seek = eb * mtd->eb_size + offs;
+       if (lseek(mtd->fd, seek, SEEK_SET) != seek) {
+               sys_errmsg("cannot seek mtd%d to offset %llu",
+                          mtd->num, (unsigned long long)seek);
+               return -1;
+       }
+
+       ret = write(mtd->fd, buf, len);
+       if (ret != len) {
+               sys_errmsg("cannot write %d bytes to mtd%d (eraseblock %d, offset %d)",
+                          len, mtd->num, eb, offs);
+               return -1;
+       }
+
+       return 0;
+}