Cross Reference: /lib/scatterlist.c

Lines Matching refs:miter
446  * @miter: sg mapping iter to be started
451  *   Starts mapping iterator @miter.
456 void sg_miter_start(struct sg_mapping_iter *miter, struct scatterlist *sgl,
459 	memset(miter, 0, sizeof(struct sg_mapping_iter));
461 	__sg_page_iter_start(&miter->piter, sgl, nents, 0);
463 	miter->__flags = flags;
467 static bool sg_miter_get_next_page(struct sg_mapping_iter *miter)
469 	if (!miter->__remaining) {
473 		if (!__sg_page_iter_next(&miter->piter))
476 		sg = miter->piter.sg;
477 		pgoffset = miter->piter.sg_pgoffset;
479 		miter->__offset = pgoffset ? 0 : sg->offset;
480 		miter->__remaining = sg->offset + sg->length -
481 				(pgoffset << PAGE_SHIFT) - miter->__offset;
482 		miter->__remaining = min_t(unsigned long, miter->__remaining,
483 					   PAGE_SIZE - miter->__offset);
491  * @miter: sg mapping iter to be skipped
495  *   Sets the offset of @miter to its current location plus @offset bytes.
496  *   If mapping iterator @miter has been proceeded by sg_miter_next(), this
497  *   stops @miter.
500  *   Don't care if @miter is stopped, or not proceeded yet.
504  *   true if @miter contains the valid mapping.  false if end of sg
507 bool sg_miter_skip(struct sg_mapping_iter *miter, off_t offset)
509 	sg_miter_stop(miter);
514 		if (!sg_miter_get_next_page(miter))
517 		consumed = min_t(off_t, offset, miter->__remaining);
518 		miter->__offset += consumed;
519 		miter->__remaining -= consumed;
529  * @miter: sg mapping iter to proceed
532  *   Proceeds @miter to the next mapping.  @miter should have been started
533  *   using sg_miter_start().  On successful return, @miter->page,
534  *   @miter->addr and @miter->length point to the current mapping.
538  *   till @miter is stopped.  May sleep if !SG_MITER_ATOMIC.
541  *   true if @miter contains the next mapping.  false if end of sg
544 bool sg_miter_next(struct sg_mapping_iter *miter)
546 	sg_miter_stop(miter);
552 	if (!sg_miter_get_next_page(miter))
555 	miter->page = sg_page_iter_page(&miter->piter);
556 	miter->consumed = miter->length = miter->__remaining;
558 	if (miter->__flags & SG_MITER_ATOMIC)
559 		miter->addr = kmap_atomic(miter->page) + miter->__offset;
561 		miter->addr = kmap(miter->page) + miter->__offset;
569  * @miter: sg mapping iter to be stopped
572  *   Stops mapping iterator @miter.  @miter should have been started
581 void sg_miter_stop(struct sg_mapping_iter *miter)
583 	WARN_ON(miter->consumed > miter->length);
586 	if (miter->addr) {
587 		miter->__offset += miter->consumed;
588 		miter->__remaining -= miter->consumed;
590 		if ((miter->__flags & SG_MITER_TO_SG) &&
591 		    !PageSlab(miter->page))
592 			flush_kernel_dcache_page(miter->page);
594 		if (miter->__flags & SG_MITER_ATOMIC) {
596 			kunmap_atomic(miter->addr);
598 			kunmap(miter->page);
600 		miter->page = NULL;
601 		miter->addr = NULL;
602 		miter->length = 0;
603 		miter->consumed = 0;
626 	struct sg_mapping_iter miter;
635 	sg_miter_start(&miter, sgl, nents, sg_flags);
637 	if (!sg_miter_skip(&miter, skip))
642 	while (sg_miter_next(&miter) && offset < buflen) {
645 		len = min(miter.length, buflen - offset);
648 			memcpy(buf + offset, miter.addr, len);
650 			memcpy(miter.addr, buf + offset, len);
655 	sg_miter_stop(&miter);