From mboxrd@z Thu Jan 1 00:00:00 1970 From: michaelc@cs.wisc.edu Subject: [PATCH 1/1] libiscsi_tcp: use kmap in xmit path Date: Thu, 17 Mar 2011 16:22:17 -0500 Message-ID: <1300396937-11869-1-git-send-email-michaelc@cs.wisc.edu> Return-path: Received: from mx1.redhat.com ([209.132.183.28]:26726 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755473Ab1CQVV4 (ORCPT ); Thu, 17 Mar 2011 17:21:56 -0400 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org Cc: Mike Christie From: Mike Christie The xmit path can sleep with a page kmapped in the network xmit code while it waits for space to open up, so we have to use kmap instead of kmap atomic in that path. Signed-off-by: Mike Christie --- drivers/scsi/libiscsi_tcp.c | 15 +++++++++++++-- include/scsi/libiscsi_tcp.h | 1 + 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/libiscsi_tcp.c b/drivers/scsi/libiscsi_tcp.c index 8eeb39f..e98ae33 100644 --- a/drivers/scsi/libiscsi_tcp.c +++ b/drivers/scsi/libiscsi_tcp.c @@ -132,14 +132,25 @@ static void iscsi_tcp_segment_map(struct iscsi_segment *segment, int recv) if (page_count(sg_page(sg)) >= 1 && !recv) return; - segment->sg_mapped = kmap_atomic(sg_page(sg), KM_SOFTIRQ0); + if (recv) { + segment->atomic_mapped = true; + segment->sg_mapped = kmap_atomic(sg_page(sg), KM_SOFTIRQ0); + } else { + segment->atomic_mapped = false; + /* the xmit path can sleep with the page mapped so use kmap */ + segment->sg_mapped = kmap(sg_page(sg)); + } + segment->data = segment->sg_mapped + sg->offset + segment->sg_offset; } void iscsi_tcp_segment_unmap(struct iscsi_segment *segment) { if (segment->sg_mapped) { - kunmap_atomic(segment->sg_mapped, KM_SOFTIRQ0); + if (segment->atomic_mapped) + kunmap_atomic(segment->sg_mapped, KM_SOFTIRQ0); + else + kunmap(sg_page(segment->sg)); segment->sg_mapped = NULL; segment->data = NULL; } diff --git a/include/scsi/libiscsi_tcp.h b/include/scsi/libiscsi_tcp.h index 741ae7e..e6b9fd2 100644 --- a/include/scsi/libiscsi_tcp.h +++ b/include/scsi/libiscsi_tcp.h @@ -47,6 +47,7 @@ struct iscsi_segment { struct scatterlist *sg; void *sg_mapped; unsigned int sg_offset; + bool atomic_mapped; iscsi_segment_done_fn_t *done; }; -- 1.7.2.3