Commit 2d78aee4 authored by Boris Brezillon's avatar Boris Brezillon Committed by Richard Weinberger
Browse files

UBI: simplify LEB write and atomic LEB change code 



ubi_eba_write_leb(), ubi_eba_write_leb_st() and
ubi_eba_atomic_leb_change() are using a convoluted retry/exit path.
Add the try_write_vid_and_data() function to simplify the retry logic
and make sure we have a single exit path instead of manually releasing
the resources in each error path.

Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
parent f036dfeb

drivers/mtd/ubi/eba.c

+115 −170
Original line number Diff line number Diff line
@@ -692,6 +692,69 @@ static int recover_peb(struct ubi_device *ubi, int pnum, int vol_id, int lnum, 
	return err;

}



/**

 * try_write_vid_and_data - try to write VID header and data to a new PEB.

 * @vol: volume description object

 * @lnum: logical eraseblock number

 * @vid_hdr: VID header to write

 * @buf: buffer containing the data

 * @offset: where to start writing data

 * @len: how many bytes should be written

 *

 * This function tries to write VID header and data belonging to logical

 * eraseblock @lnum of volume @vol to a new physical eraseblock. Returns zero

 * in case of success and a negative error code in case of failure.

 * In case of error, it is possible that something was still written to the

 * flash media, but may be some garbage.

 */

static int try_write_vid_and_data(struct ubi_volume *vol, int lnum,

				  struct ubi_vid_hdr *vid_hdr, const void *buf,

				  int offset, int len)

{

	struct ubi_device *ubi = vol->ubi;

	int pnum, opnum, err, vol_id = vol->vol_id;



	pnum = ubi_wl_get_peb(ubi);

	if (pnum < 0) {

		err = pnum;

		goto out_put;

	}



	opnum = vol->eba_tbl[lnum];



	dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d",

		len, offset, vol_id, lnum, pnum);



	err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);

	if (err) {

		ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d",

			 vol_id, lnum, pnum);

		goto out_put;

	}



	if (len) {

		err = ubi_io_write_data(ubi, buf, pnum, offset, len);

		if (err) {

			ubi_warn(ubi,

				 "failed to write %d bytes at offset %d of LEB %d:%d, PEB %d",

				 len, offset, vol_id, lnum, pnum);

			goto out_put;

		}

	}



	vol->eba_tbl[lnum] = pnum;



out_put:

	up_read(&ubi->fm_eba_sem);



	if (err && pnum >= 0)

		err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1);

	else if (!err && opnum >= 0)

		err = ubi_wl_put_peb(ubi, vol_id, lnum, opnum, 0);



	return err;

}



/**

 * ubi_eba_write_leb - write data to dynamic volume.

 * @ubi: UBI device description object
@@ -705,11 +768,12 @@ static int recover_peb(struct ubi_device *ubi, int pnum, int vol_id, int lnum, 
 * @vol. Returns zero in case of success and a negative error code in case

 * of failure. In case of error, it is possible that something was still

 * written to the flash media, but may be some garbage.

 * This function retries %UBI_IO_RETRIES times before giving up.

 */

int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,

		      const void *buf, int offset, int len)

{

	int err, pnum, tries = 0, vol_id = vol->vol_id;

	int err, pnum, tries, vol_id = vol->vol_id;

	struct ubi_vid_hdr *vid_hdr;



	if (ubi->ro_mode)
@@ -730,11 +794,9 @@ int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, 
			if (err == -EIO && ubi->bad_allowed)

				err = recover_peb(ubi, pnum, vol_id, lnum, buf,

						  offset, len);

			if (err)

				ubi_ro_mode(ubi);

		}

		leb_write_unlock(ubi, vol_id, lnum);

		return err;



		goto out;

	}



	/*
@@ -754,67 +816,31 @@ int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, 
	vid_hdr->compat = ubi_get_compat(ubi, vol_id);

	vid_hdr->data_pad = cpu_to_be32(vol->data_pad);



retry:

	pnum = ubi_wl_get_peb(ubi);

	if (pnum < 0) {

		ubi_free_vid_hdr(ubi, vid_hdr);

		leb_write_unlock(ubi, vol_id, lnum);

		up_read(&ubi->fm_eba_sem);

		return pnum;

	}



	dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d",

		len, offset, vol_id, lnum, pnum);



	err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);

	if (err) {

		ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d",

			 vol_id, lnum, pnum);

		up_read(&ubi->fm_eba_sem);

		goto write_error;

	}

	for (tries = 0; tries <= UBI_IO_RETRIES; tries++) {

		err = try_write_vid_and_data(vol, lnum, vid_hdr, buf, offset,

					     len);

		if (err != -EIO || !ubi->bad_allowed)

			break;



	if (len) {

		err = ubi_io_write_data(ubi, buf, pnum, offset, len);

		if (err) {

			ubi_warn(ubi, "failed to write %d bytes at offset %d of LEB %d:%d, PEB %d",

				 len, offset, vol_id, lnum, pnum);

			up_read(&ubi->fm_eba_sem);

			goto write_error;

		}

		/*

		 * Fortunately, this is the first write operation to this

		 * physical eraseblock, so just put it and request a new one.

		 * We assume that if this physical eraseblock went bad, the

		 * erase code will handle that.

		 */

		vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));

		ubi_msg(ubi, "try another PEB");

	}



	vol->eba_tbl[lnum] = pnum;

	up_read(&ubi->fm_eba_sem);



	leb_write_unlock(ubi, vol_id, lnum);

	ubi_free_vid_hdr(ubi, vid_hdr);

	return 0;



write_error:

	if (err != -EIO || !ubi->bad_allowed) {

out:

	if (err)

		ubi_ro_mode(ubi);

		leb_write_unlock(ubi, vol_id, lnum);

		ubi_free_vid_hdr(ubi, vid_hdr);

		return err;

	}



	/*

	 * Fortunately, this is the first write operation to this physical

	 * eraseblock, so just put it and request a new one. We assume that if

	 * this physical eraseblock went bad, the erase code will handle that.

	 */

	err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1);

	if (err || ++tries > UBI_IO_RETRIES) {

		ubi_ro_mode(ubi);

	leb_write_unlock(ubi, vol_id, lnum);

		ubi_free_vid_hdr(ubi, vid_hdr);

		return err;

	}



	vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));

	ubi_msg(ubi, "try another PEB");

	goto retry;

	return err;

}



/**
@@ -842,7 +868,7 @@ write_error: 
int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,

			 int lnum, const void *buf, int len, int used_ebs)

{

	int err, pnum, tries = 0, data_size = len, vol_id = vol->vol_id;

	int err, tries, data_size = len, vol_id = vol->vol_id;

	struct ubi_vid_hdr *vid_hdr;

	uint32_t crc;
@@ -860,10 +886,8 @@ int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol, 
		return -ENOMEM;



	err = leb_write_lock(ubi, vol_id, lnum);

	if (err) {

		ubi_free_vid_hdr(ubi, vid_hdr);

		return err;

	}

	if (err)

		goto out;



	vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));

	vid_hdr->vol_id = cpu_to_be32(vol_id);
@@ -877,68 +901,28 @@ int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol, 
	vid_hdr->used_ebs = cpu_to_be32(used_ebs);

	vid_hdr->data_crc = cpu_to_be32(crc);



retry:

	pnum = ubi_wl_get_peb(ubi);

	if (pnum < 0) {

		ubi_free_vid_hdr(ubi, vid_hdr);

		leb_write_unlock(ubi, vol_id, lnum);

		up_read(&ubi->fm_eba_sem);

		return pnum;

	}



	dbg_eba("write VID hdr and %d bytes at LEB %d:%d, PEB %d, used_ebs %d",

		len, vol_id, lnum, pnum, used_ebs);

	ubi_assert(vol->eba_tbl[lnum] < 0);



	err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);

	if (err) {

		ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d",

			 vol_id, lnum, pnum);

		up_read(&ubi->fm_eba_sem);

		goto write_error;

	}

	for (tries = 0; tries <= UBI_IO_RETRIES; tries++) {

		err = try_write_vid_and_data(vol, lnum, vid_hdr, buf, 0, len);

		if (err != -EIO || !ubi->bad_allowed)

			break;



	err = ubi_io_write_data(ubi, buf, pnum, 0, len);

	if (err) {

		ubi_warn(ubi, "failed to write %d bytes of data to PEB %d",

			 len, pnum);

		up_read(&ubi->fm_eba_sem);

		goto write_error;

		vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));

		ubi_msg(ubi, "try another PEB");

	}



	ubi_assert(vol->eba_tbl[lnum] < 0);

	vol->eba_tbl[lnum] = pnum;

	up_read(&ubi->fm_eba_sem);

	if (err)

		ubi_ro_mode(ubi);



	leb_write_unlock(ubi, vol_id, lnum);

	ubi_free_vid_hdr(ubi, vid_hdr);

	return 0;



write_error:

	if (err != -EIO || !ubi->bad_allowed) {

		/*

		 * This flash device does not admit of bad eraseblocks or

		 * something nasty and unexpected happened. Switch to read-only

		 * mode just in case.

		 */

		ubi_ro_mode(ubi);

		leb_write_unlock(ubi, vol_id, lnum);

out:

	ubi_free_vid_hdr(ubi, vid_hdr);

		return err;

	}



	err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1);

	if (err || ++tries > UBI_IO_RETRIES) {

		ubi_ro_mode(ubi);

		leb_write_unlock(ubi, vol_id, lnum);

		ubi_free_vid_hdr(ubi, vid_hdr);

	return err;

}



	vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));

	ubi_msg(ubi, "try another PEB");

	goto retry;

}



/*

 * ubi_eba_atomic_leb_change - change logical eraseblock atomically.

 * @ubi: UBI device description object
@@ -959,7 +943,7 @@ write_error: 
int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,

			      int lnum, const void *buf, int len)

{

	int err, pnum, old_pnum, tries = 0, vol_id = vol->vol_id;

	int err, tries, vol_id = vol->vol_id;

	struct ubi_vid_hdr *vid_hdr;

	uint32_t crc;
@@ -998,70 +982,31 @@ int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol, 
	vid_hdr->copy_flag = 1;

	vid_hdr->data_crc = cpu_to_be32(crc);



retry:

	pnum = ubi_wl_get_peb(ubi);

	if (pnum < 0) {

		err = pnum;

		up_read(&ubi->fm_eba_sem);

		goto out_leb_unlock;

	}



	dbg_eba("change LEB %d:%d, PEB %d, write VID hdr to PEB %d",

		vol_id, lnum, vol->eba_tbl[lnum], pnum);



	err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);

	if (err) {

		ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d",

			 vol_id, lnum, pnum);

		up_read(&ubi->fm_eba_sem);

		goto write_error;

	}

	dbg_eba("change LEB %d:%d", vol_id, lnum);



	err = ubi_io_write_data(ubi, buf, pnum, 0, len);

	if (err) {

		ubi_warn(ubi, "failed to write %d bytes of data to PEB %d",

			 len, pnum);

		up_read(&ubi->fm_eba_sem);

		goto write_error;

	}



	old_pnum = vol->eba_tbl[lnum];

	vol->eba_tbl[lnum] = pnum;

	up_read(&ubi->fm_eba_sem);

	for (tries = 0; tries <= UBI_IO_RETRIES; tries++) {

		err = try_write_vid_and_data(vol, lnum, vid_hdr, buf, 0, len);

		if (err != -EIO || !ubi->bad_allowed)

			break;



	if (old_pnum >= 0) {

		err = ubi_wl_put_peb(ubi, vol_id, lnum, old_pnum, 0);

		if (err)

			goto out_leb_unlock;

		vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));

		ubi_msg(ubi, "try another PEB");

	}



out_leb_unlock:

	leb_write_unlock(ubi, vol_id, lnum);

out_mutex:

	mutex_unlock(&ubi->alc_mutex);

	ubi_free_vid_hdr(ubi, vid_hdr);

	return err;



write_error:

	if (err != -EIO || !ubi->bad_allowed) {

	/*

	 * This flash device does not admit of bad eraseblocks or

	 * something nasty and unexpected happened. Switch to read-only

	 * mode just in case.

	 */

	if (err)

		ubi_ro_mode(ubi);

		goto out_leb_unlock;

	}



	err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1);

	if (err || ++tries > UBI_IO_RETRIES) {

		ubi_ro_mode(ubi);

		goto out_leb_unlock;

	}

	leb_write_unlock(ubi, vol_id, lnum);



	vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));

	ubi_msg(ubi, "try another PEB");

	goto retry;

out_mutex:

	mutex_unlock(&ubi->alc_mutex);

	ubi_free_vid_hdr(ubi, vid_hdr);

	return err;

}



/**

CRA Git | Maintained and supported by SUSTech CRA and CCSE