libata sg chaining support fix (0874ee76) · Commits · 戴 / test

drivers/ata/libata-core.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -4952,16 +4952,18 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
		{
		int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
		struct scatterlist *sg = qc->__sg;
		struct scatterlist *lsg = sg_last(qc->__sg, qc->n_elem);
		struct ata_port *ap = qc->ap;
		struct page *page;
		unsigned char *buf;
		unsigned int offset, count;
		int no_more_sg = 0;

		if (qc->curbytes + bytes >= qc->nbytes)
		ap->hsm_task_state = HSM_ST_LAST;

		next_sg:
		if (unlikely(qc->cursg == sg_last(qc->__sg, qc->n_elem))) {
		if (unlikely(no_more_sg)) {
		/*
		* The end of qc->sg is reached and the device expects
		* more data to transfer. In order not to overrun qc->sg
		@@ -5023,6 +5025,9 @@ next_sg:
		qc->cursg_ofs += count;

		if (qc->cursg_ofs == sg->length) {
		if (qc->cursg == lsg)
		no_more_sg = 1;

		qc->cursg = sg_next(qc->cursg);
		qc->cursg_ofs = 0;
		}