From f276730f8da0e8136d8491b6ef44fc719d450a1b Mon Sep 17 00:00:00 2001 From: "Klaus D. Wacker" Date: Wed, 22 Aug 2007 13:51:38 +0200 Subject: [PATCH] [S390] qdio: fix EQBS handling on CCQ96 QDIO returned from EQBS instruction in any case after return code CCQ=96 was issued regardless whether buffer states for at least one buffer were extracted or not. This caused FCP devices to hang when running under z/VM and having QIOASSASIST=ON and having high I/O rates. In order to fix this qdio return code processing of EQBS instruction after CCQ=96 is changed that buffers are returned and if no buffers where extracted the instruction is repeated at once. Signed-off-by: Klaus D. Wacker Signed-off-by: Martin Schwidefsky Signed-off-by: Heiko Carstens --- drivers/s390/cio/qdio.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/s390/cio/qdio.c b/drivers/s390/cio/qdio.c index 03347aed2b3e..badfb5b21304 100644 --- a/drivers/s390/cio/qdio.c +++ b/drivers/s390/cio/qdio.c @@ -195,6 +195,8 @@ qdio_do_eqbs(struct qdio_q *q, unsigned char *state, again: ccq = do_eqbs(irq->sch_token, state, q_no, start, cnt); rc = qdio_check_ccq(q, ccq); + if ((ccq == 96) && (tmp_cnt != *cnt)) + rc = 0; if (rc == 1) { QDIO_DBF_TEXT5(1,trace,"eqAGAIN"); goto again; -- 2.30.2