From 19645a077120c6417e9dc5ad469c45194cf78a82 Mon Sep 17 00:00:00 2001 From: Logan Gunthorpe Date: Tue, 7 Jun 2016 11:20:22 -0600 Subject: [PATCH] ntb_transport: Check the number of spads the hardware supports I'm working on hardware that currently has a limited number of scratchpad registers and ntb_ndev fails with no clue as to why. I feel it is better to fail early and provide a reasonable error message then to fail later on. The same is done to ntb_perf, but it doesn't currently require enough spads to actually fail. I've also removed the unused SPAD_MSG and SPAD_ACK enums so that MAX_SPAD accurately reflects the number of spads used. Signed-off-by: Logan Gunthorpe Acked-by: Dave Jiang Signed-off-by: Jon Mason --- drivers/ntb/ntb_transport.c | 9 +++++++-- drivers/ntb/test/ntb_perf.c | 8 ++++++-- 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c index 6db8c8528f26..d5c5894f252e 100644 --- a/drivers/ntb/ntb_transport.c +++ b/drivers/ntb/ntb_transport.c @@ -1060,6 +1060,13 @@ static int ntb_transport_probe(struct ntb_client *self, struct ntb_dev *ndev) int node; int rc, i; + mw_count = ntb_mw_count(ndev); + if (ntb_spad_count(ndev) < (NUM_MWS + 1 + mw_count * 2)) { + dev_err(&ndev->dev, "Not enough scratch pad registers for %s", + NTB_TRANSPORT_NAME); + return -EIO; + } + if (ntb_db_is_unsafe(ndev)) dev_dbg(&ndev->dev, "doorbell is unsafe, proceed anyway...\n"); @@ -1075,8 +1082,6 @@ static int ntb_transport_probe(struct ntb_client *self, struct ntb_dev *ndev) nt->ndev = ndev; - mw_count = ntb_mw_count(ndev); - nt->mw_count = mw_count; nt->mw_vec = kzalloc_node(mw_count * sizeof(*nt->mw_vec), diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c index 30635c89320c..4368519da102 100644 --- a/drivers/ntb/test/ntb_perf.c +++ b/drivers/ntb/test/ntb_perf.c @@ -143,8 +143,6 @@ enum { VERSION = 0, MW_SZ_HIGH, MW_SZ_LOW, - SPAD_MSG, - SPAD_ACK, MAX_SPAD }; @@ -696,6 +694,12 @@ static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb) int node; int rc = 0; + if (ntb_spad_count(ntb) < MAX_SPAD) { + dev_err(&ntb->dev, "Not enough scratch pad registers for %s", + DRIVER_NAME); + return -EIO; + } + node = dev_to_node(&pdev->dev); perf = kzalloc_node(sizeof(*perf), GFP_KERNEL, node); -- 2.20.1