From 1bb665e3dd67f6f3477c55c2b247b42b1a5bfc95 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Tue, 21 Mar 2017 17:59:15 -0700 Subject: [PATCH] nfp: fix invalid area detection Core should detect when someone is trying to request an access window which is too large for a given type of access. Otherwise the requester will be put on a wait queue for ever without any error message. Add const qualifiers to clarify that we are only looking at read- -only members in relevant functions. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- .../netronome/nfp/nfpcore/nfp6000_pcie.c | 29 ++++++++++--------- 1 file changed, 15 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c index 15cc3e77cf6a..43dc68e01274 100644 --- a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c +++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c @@ -217,7 +217,7 @@ static resource_size_t nfp_bar_resource_start(struct nfp_bar *bar) #define TARGET_WIDTH_64 8 static int -compute_bar(struct nfp6000_pcie *nfp, struct nfp_bar *bar, +compute_bar(const struct nfp6000_pcie *nfp, const struct nfp_bar *bar, u32 *bar_config, u64 *bar_base, int tgt, int act, int tok, u64 offset, size_t size, int width) { @@ -410,35 +410,36 @@ find_matching_bar(struct nfp6000_pcie *nfp, /* Return EAGAIN if no resource is available */ static int -find_unused_bar_noblock(struct nfp6000_pcie *nfp, +find_unused_bar_noblock(const struct nfp6000_pcie *nfp, int tgt, int act, int tok, u64 offset, size_t size, int width) { - int n, invalid = 0; + int n, busy = 0; for (n = 0; n < nfp->bars; n++) { - struct nfp_bar *bar = &nfp->bar[n]; + const struct nfp_bar *bar = &nfp->bar[n]; int err; - if (bar->bitsize == 0) { - invalid++; - continue; - } - - if (atomic_read(&bar->refcnt) != 0) + if (!bar->bitsize) continue; /* Just check to see if we can make it fit... */ err = compute_bar(nfp, bar, NULL, NULL, tgt, act, tok, offset, size, width); + if (err) + continue; - if (err < 0) - invalid++; - else + if (!atomic_read(&bar->refcnt)) return n; + + busy++; } - return (n == invalid) ? -EINVAL : -EAGAIN; + if (WARN(!busy, "No suitable BAR found for request tgt:0x%x act:0x%x tok:0x%x off:0x%llx size:%zd width:%d\n", + tgt, act, tok, offset, size, width)) + return -EINVAL; + + return -EAGAIN; } static int