Esempio n. 1
0
/**
 * ubifs_wbuf_write_nolock - write data to flash via write-buffer.
 * @wbuf: write-buffer
 * @buf: node to write
 * @len: node length
 *
 * This function writes data to flash via write-buffer @wbuf. This means that
 * the last piece of the node won't reach the flash media immediately if it
 * does not take whole max. write unit (@c->max_write_size). Instead, the node
 * will sit in RAM until the write-buffer is synchronized (e.g., by timer, or
 * because more data are appended to the write-buffer).
 *
 * This function returns zero in case of success and a negative error code in
 * case of failure. If the node cannot be written because there is no more
 * space in this logical eraseblock, %-ENOSPC is returned.
 */
int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len)
{
	struct ubifs_info *c = wbuf->c;
	int err, written, n, aligned_len = ALIGN(len, 8);

	dbg_io("%d bytes (%s) to jhead %s wbuf at LEB %d:%d", len,
	       dbg_ntype(((struct ubifs_ch *)buf)->node_type),
	       dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs + wbuf->used);
	ubifs_assert(len > 0 && wbuf->lnum >= 0 && wbuf->lnum < c->leb_cnt);
	ubifs_assert(wbuf->offs >= 0 && wbuf->offs % c->min_io_size == 0);
	ubifs_assert(!(wbuf->offs & 7) && wbuf->offs <= c->leb_size);
	ubifs_assert(wbuf->avail > 0 && wbuf->avail <= wbuf->size);
	ubifs_assert(wbuf->size >= c->min_io_size);
	ubifs_assert(wbuf->size <= c->max_write_size);
	ubifs_assert(wbuf->size % c->min_io_size == 0);
	ubifs_assert(mutex_is_locked(&wbuf->io_mutex));
	ubifs_assert(!c->ro_media && !c->ro_mount);
	ubifs_assert(!c->space_fixup);
	if (c->leb_size - wbuf->offs >= c->max_write_size)
		ubifs_assert(!((wbuf->offs + wbuf->size) % c->max_write_size));

	if (c->leb_size - wbuf->offs - wbuf->used < aligned_len) {
		err = -ENOSPC;
		goto out;
	}

	cancel_wbuf_timer_nolock(wbuf);

	if (c->ro_error)
		return -EROFS;

	if (aligned_len <= wbuf->avail) {
		/*
		 * The node is not very large and fits entirely within
		 * write-buffer.
		 */
		memcpy(wbuf->buf + wbuf->used, buf, len);

		if (aligned_len == wbuf->avail) {
			dbg_io("flush jhead %s wbuf to LEB %d:%d",
			       dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs);
#if defined(FEATURE_UBIFS_PERF_INDEX)
			if(wbuf->jhead == DATAHD)
				err = ubifs_leb_write_log(c, wbuf->lnum, wbuf->buf, 
						wbuf->offs, wbuf->size);
			else
#endif
			err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf,
					      wbuf->offs, wbuf->size);
			if (err)
				goto out;
			wbuf->w_count += wbuf->size; //MTK

			spin_lock(&wbuf->lock);
			wbuf->offs += wbuf->size;
			if (c->leb_size - wbuf->offs >= c->max_write_size)
				wbuf->size = c->max_write_size;
			else
				wbuf->size = c->leb_size - wbuf->offs;
			wbuf->avail = wbuf->size;
			wbuf->used = 0;
			wbuf->next_ino = 0;
			spin_unlock(&wbuf->lock);
		} else {
			spin_lock(&wbuf->lock);
			wbuf->avail -= aligned_len;
			wbuf->used += aligned_len;
			spin_unlock(&wbuf->lock);
		}

		goto exit;
	}

	written = 0;

	if (wbuf->used) {
		/*
		 * The node is large enough and does not fit entirely within
		 * current available space. We have to fill and flush
		 * write-buffer and switch to the next max. write unit.
		 */
		dbg_io("flush jhead %s wbuf to LEB %d:%d",
		       dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs);
		memcpy(wbuf->buf + wbuf->used, buf, wbuf->avail);
#if defined(FEATURE_UBIFS_PERF_INDEX)
	if(wbuf->jhead == DATAHD)
		err = ubifs_leb_write_log(c, wbuf->lnum, wbuf->buf, wbuf->offs, 
			                  wbuf->size);
	else
#endif
		err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf, wbuf->offs,
				      wbuf->size);
		if (err)
			goto out;
		wbuf->w_count += wbuf->size; //MTK

		wbuf->offs += wbuf->size;
		len -= wbuf->avail;
		aligned_len -= wbuf->avail;
		written += wbuf->avail;
	} else if (wbuf->offs & (c->max_write_size - 1)) {
		/*
		 * The write-buffer offset is not aligned to
		 * @c->max_write_size and @wbuf->size is less than
		 * @c->max_write_size. Write @wbuf->size bytes to make sure the
		 * following writes are done in optimal @c->max_write_size
		 * chunks.
		 */
		dbg_io("write %d bytes to LEB %d:%d",
		       wbuf->size, wbuf->lnum, wbuf->offs);
#if defined(FEATURE_UBIFS_PERF_INDEX)
	if(wbuf->jhead == DATAHD)
		err = ubifs_leb_write_log(c, wbuf->lnum, wbuf->buf, wbuf->offs, 
			                  wbuf->size);
	else
#endif
		err = ubifs_leb_write(c, wbuf->lnum, buf, wbuf->offs,
				      wbuf->size);
		if (err)
			goto out;
		wbuf->w_count += wbuf->size; //MTK

		wbuf->offs += wbuf->size;
		len -= wbuf->size;
		aligned_len -= wbuf->size;
		written += wbuf->size;
	}

	/*
	 * The remaining data may take more whole max. write units, so write the
	 * remains multiple to max. write unit size directly to the flash media.
	 * We align node length to 8-byte boundary because we anyway flash wbuf
	 * if the remaining space is less than 8 bytes.
	 */
	n = aligned_len >> c->max_write_shift;
	if (n) {
		n <<= c->max_write_shift;
		dbg_io("write %d bytes to LEB %d:%d", n, wbuf->lnum,
		       wbuf->offs);
#if defined(FEATURE_UBIFS_PERF_INDEX)
	if(wbuf->jhead == DATAHD)
		err = ubifs_leb_write_log(c, wbuf->lnum, buf + written,
				          wbuf->offs, n);
	else
#endif
		err = ubifs_leb_write(c, wbuf->lnum, buf + written,
				      wbuf->offs, n);
		if (err)
			goto out;
		wbuf->w_count += n; //MTK
		wbuf->offs += n;
		aligned_len -= n;
		len -= n;
		written += n;
	}

	spin_lock(&wbuf->lock);
	if (aligned_len)
		/*
		 * And now we have what's left and what does not take whole
		 * max. write unit, so write it to the write-buffer and we are
		 * done.
		 */
		memcpy(wbuf->buf, buf + written, len);

	if (c->leb_size - wbuf->offs >= c->max_write_size)
		wbuf->size = c->max_write_size;
	else
		wbuf->size = c->leb_size - wbuf->offs;
	wbuf->avail = wbuf->size - aligned_len;
	wbuf->used = aligned_len;
	wbuf->next_ino = 0;
	spin_unlock(&wbuf->lock);

exit:
	if (wbuf->sync_callback) {
		int free = c->leb_size - wbuf->offs - wbuf->used;

		err = wbuf->sync_callback(c, wbuf->lnum, free, 0);
		if (err)
			goto out;
	}

	if (wbuf->used)
		new_wbuf_timer_nolock(wbuf);

	return 0;

out:
	ubifs_err("cannot write %d bytes to LEB %d:%d, error %d",
		  len, wbuf->lnum, wbuf->offs, err);
	dbg_dump_node(c, buf);
	dbg_dump_stack();
	dbg_dump_leb(c, wbuf->lnum);
	return err;
}
Esempio n. 2
0
File: io.c Progetto: aircross/ray
/**
 * ubifs_wbuf_write_nolock - write data to flash via write-buffer.
 * @wbuf: write-buffer
 * @buf: node to write
 * @len: node length
 *
 * This function writes data to flash via write-buffer @wbuf. This means that
 * the last piece of the node won't reach the flash media immediately if it
 * does not take whole minimal I/O unit. Instead, the node will sit in RAM
 * until the write-buffer is synchronized (e.g., by timer).
 *
 * This function returns zero in case of success and a negative error code in
 * case of failure. If the node cannot be written because there is no more
 * space in this logical eraseblock, %-ENOSPC is returned.
 */
int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len)
{
	struct ubifs_info *c = wbuf->c;
	int err, written, n, aligned_len = ALIGN(len, 8), offs;

	dbg_io("%d bytes (%s) to wbuf at LEB %d:%d", len,
	       dbg_ntype(((struct ubifs_ch *)buf)->node_type), wbuf->lnum,
	       wbuf->offs + wbuf->used);
	ubifs_assert(len > 0 && wbuf->lnum >= 0 && wbuf->lnum < c->leb_cnt);
	ubifs_assert(wbuf->offs >= 0 && wbuf->offs % c->min_io_size == 0);
	ubifs_assert(!(wbuf->offs & 7) && wbuf->offs <= c->leb_size);
	ubifs_assert(wbuf->avail > 0 && wbuf->avail <= c->min_io_size);
	ubifs_assert(mutex_is_locked(&wbuf->io_mutex));

	if (c->leb_size - wbuf->offs - wbuf->used < aligned_len) {
		err = -ENOSPC;
		goto out;
	}

	cancel_wbuf_timer_nolock(wbuf);

	if (c->ro_media)
		return -EROFS;

	if (aligned_len <= wbuf->avail) {
		/*
		 * The node is not very large and fits entirely within
		 * write-buffer.
		 */
		memcpy(wbuf->buf + wbuf->used, buf, len);

		if (aligned_len == wbuf->avail) {
			dbg_io("flush wbuf to LEB %d:%d", wbuf->lnum,
				wbuf->offs);
			err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf,
					    wbuf->offs, c->min_io_size,
					    wbuf->dtype);
			if (err)
				goto out;

			spin_lock(&wbuf->lock);
			wbuf->offs += c->min_io_size;
			wbuf->avail = c->min_io_size;
			wbuf->used = 0;
			wbuf->next_ino = 0;
			spin_unlock(&wbuf->lock);
		} else {
			spin_lock(&wbuf->lock);
			wbuf->avail -= aligned_len;
			wbuf->used += aligned_len;
			spin_unlock(&wbuf->lock);
		}

		goto exit;
	}

	/*
	 * The node is large enough and does not fit entirely within current
	 * minimal I/O unit. We have to fill and flush write-buffer and switch
	 * to the next min. I/O unit.
	 */
	dbg_io("flush wbuf to LEB %d:%d", wbuf->lnum, wbuf->offs);
	memcpy(wbuf->buf + wbuf->used, buf, wbuf->avail);
	err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf, wbuf->offs,
			    c->min_io_size, wbuf->dtype);
	if (err)
		goto out;

	offs = wbuf->offs + c->min_io_size;
	len -= wbuf->avail;
	aligned_len -= wbuf->avail;
	written = wbuf->avail;

	/*
	 * The remaining data may take more whole min. I/O units, so write the
	 * remains multiple to min. I/O unit size directly to the flash media.
	 * We align node length to 8-byte boundary because we anyway flash wbuf
	 * if the remaining space is less than 8 bytes.
	 */
	n = aligned_len >> c->min_io_shift;
	if (n) {
		n <<= c->min_io_shift;
		dbg_io("write %d bytes to LEB %d:%d", n, wbuf->lnum, offs);
		err = ubi_leb_write(c->ubi, wbuf->lnum, buf + written, offs, n,
				    wbuf->dtype);
		if (err)
			goto out;
		offs += n;
		aligned_len -= n;
		len -= n;
		written += n;
	}

	spin_lock(&wbuf->lock);
	if (aligned_len)
		/*
		 * And now we have what's left and what does not take whole
		 * min. I/O unit, so write it to the write-buffer and we are
		 * done.
		 */
		memcpy(wbuf->buf, buf + written, len);

	wbuf->offs = offs;
	wbuf->used = aligned_len;
	wbuf->avail = c->min_io_size - aligned_len;
	wbuf->next_ino = 0;
	spin_unlock(&wbuf->lock);

exit:
	if (wbuf->sync_callback) {
		int free = c->leb_size - wbuf->offs - wbuf->used;

		err = wbuf->sync_callback(c, wbuf->lnum, free, 0);
		if (err)
			goto out;
	}

	if (wbuf->used)
		new_wbuf_timer_nolock(wbuf);

	return 0;

out:
	ubifs_err("cannot write %d bytes to LEB %d:%d, error %d",
		  len, wbuf->lnum, wbuf->offs, err);
	dbg_dump_node(c, buf);
	dbg_dump_stack();
	dbg_dump_leb(c, wbuf->lnum);
	return err;
}