Пример #1
0
/**
 * ubi_io_write - write data to a physical eraseblock.
 * @ubi: UBI device description object
 * @buf: buffer with the data to write
 * @pnum: physical eraseblock number to write to
 * @offset: offset within the physical eraseblock where to write
 * @len: how many bytes to write
 *
 * This function writes @len bytes of data from buffer @buf to offset @offset
 * of physical eraseblock @pnum. If all the data were successfully written,
 * zero is returned. If an error occurred, this function returns a negative
 * error code. If %-EIO is returned, the physical eraseblock most probably went
 * bad.
 *
 * Note, in case of an error, it is possible that something was still written
 * to the flash media, but may be some garbage.
 */
int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
		 int len)
{
	int err;
	size_t written;
	loff_t addr;

	dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset);

	ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
	ubi_assert(offset >= 0 && offset + len <= ubi->peb_size);
	ubi_assert(offset % ubi->hdrs_min_io_size == 0);
	ubi_assert(len > 0 && len % ubi->hdrs_min_io_size == 0);

	if (ubi->ro_mode) {
		ubi_err(ubi, "read-only mode");
		return -EROFS;
	}

	err = self_check_not_bad(ubi, pnum);
	if (err)
		return err;

	/* The area we are writing to has to contain all 0xFF bytes */
	err = ubi_self_check_all_ff(ubi, pnum, offset, len);
	if (err)
		return err;

	if (offset >= ubi->leb_start) {
		/*
		 * We write to the data area of the physical eraseblock. Make
		 * sure it has valid EC and VID headers.
		 */
		err = self_check_peb_ec_hdr(ubi, pnum);
		if (err)
			return err;
		err = self_check_peb_vid_hdr(ubi, pnum);
		if (err)
			return err;
	}

	if (ubi_dbg_is_write_failure(ubi)) {
		ubi_err(ubi, "cannot write %d bytes to PEB %d:%d (emulated)",
			len, pnum, offset);
		dump_stack();
		return -EIO;
	}

	addr = (loff_t)pnum * ubi->peb_size + offset;
	err = mtd_write(ubi->mtd, addr, len, &written, buf);
	if (err) {
		ubi_err(ubi, "error %d while writing %d bytes to PEB %d:%d, written %zd bytes",
			err, len, pnum, offset, written);
		dump_stack();
		ubi_dump_flash(ubi, pnum, offset, len);
	} else
		ubi_assert(written == len);

	if (!err) {
		err = self_check_write(ubi, buf, pnum, offset, len);
		if (err)
			return err;

		/*
		 * Since we always write sequentially, the rest of the PEB has
		 * to contain only 0xFF bytes.
		 */
		offset += len;
		len = ubi->peb_size - offset;
		if (len)
			err = ubi_self_check_all_ff(ubi, pnum, offset, len);
	}

	return err;
}
Пример #2
0
/**
 * ubi_io_write - write data to a physical eraseblock.
 * @ubi: UBI device description object
 * @buf: buffer with the data to write
 * @pnum: physical eraseblock number to write to
 * @offset: offset within the physical eraseblock where to write
 * @len: how many bytes to write
 *
 * This function writes @len bytes of data from buffer @buf to offset @offset
 * of physical eraseblock @pnum. If all the data were successfully written,
 * zero is returned. If an error occurred, this function returns a negative
 * error code. If %-EIO is returned, the physical eraseblock most probably went
 * bad.
 *
 * Note, in case of an error, it is possible that something was still written
 * to the flash media, but may be some garbage.
 */
int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
		 int len)
{
	int err;
	size_t written;
	loff_t addr;

	dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset);

	ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
	ubi_assert(offset >= 0 && offset + len <= ubi->peb_size);
	ubi_assert(offset % ubi->hdrs_min_io_size == 0);
	ubi_assert(len > 0 && len % ubi->hdrs_min_io_size == 0);

	if (ubi->ro_mode) {
		ubi_err("read-only mode");
		return -EROFS;
	}

	/* The below has to be compiled out if paranoid checks are disabled */

	err = paranoid_check_not_bad(ubi, pnum);
	if (err)
		return err > 0 ? -EINVAL : err;

	/* The area we are writing to has to contain all 0xFF bytes */
	err = paranoid_check_all_ff(ubi, pnum, offset, len);
	if (err)
		return err > 0 ? -EINVAL : err;

	if (offset >= ubi->leb_start) {
		/*
		 * We write to the data area of the physical eraseblock. Make
		 * sure it has valid EC and VID headers.
		 */
		err = paranoid_check_peb_ec_hdr(ubi, pnum);
		if (err)
			return err > 0 ? -EINVAL : err;
		err = paranoid_check_peb_vid_hdr(ubi, pnum);
		if (err)
			return err > 0 ? -EINVAL : err;
	}

	if (ubi_dbg_is_write_failure()) {
		dbg_err("cannot write %d bytes to PEB %d:%d "
			"(emulated)", len, pnum, offset);
		ubi_dbg_dump_stack();
		return -EIO;
	}

	addr = (loff_t)pnum * ubi->peb_size + offset;
	err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf);
	if (err) {
		ubi_err("error %d while writing %d bytes to PEB %d:%d, written"
			" %zd bytes", err, len, pnum, offset, written);
		ubi_dbg_dump_stack();
	} else
		ubi_assert(written == len);

	return err;
}