From 2aa2a77a489deda473c99a4c15074d092718912c Mon Sep 17 00:00:00 2001 From: Allen Hubbe Date: Mon, 31 Aug 2015 09:30:59 -0400 Subject: [PATCH] NTB: Improve index handling in B2B MW workaround Check that b2b_mw_idx is in range of the number of memory windows when initializing the device. The workaround is considered to be in effect only if the device b2b_idx is exactly UINT_MAX, instead of any index past the last memory window. Only print B2B MW workaround information in debugfs if the workaround is in effect. Signed-off-by: Allen Hubbe Signed-off-by: Jon Mason --- drivers/ntb/hw/intel/ntb_hw_intel.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.c b/drivers/ntb/hw/intel/ntb_hw_intel.c index c2bc56b67e63..fc6af2da8df0 100644 --- a/drivers/ntb/hw/intel/ntb_hw_intel.c +++ b/drivers/ntb/hw/intel/ntb_hw_intel.c @@ -575,10 +575,13 @@ static ssize_t ndev_debugfs_read(struct file *filp, char __user *ubuf, "Connection Topology -\t%s\n", ntb_topo_string(ndev->ntb.topo)); - off += scnprintf(buf + off, buf_size - off, - "B2B Offset -\t\t%#lx\n", ndev->b2b_off); - off += scnprintf(buf + off, buf_size - off, - "B2B MW Idx -\t\t%d\n", ndev->b2b_idx); + if (ndev->b2b_idx != UINT_MAX) { + off += scnprintf(buf + off, buf_size - off, + "B2B MW Idx -\t\t%u\n", ndev->b2b_idx); + off += scnprintf(buf + off, buf_size - off, + "B2B Offset -\t\t%#lx\n", ndev->b2b_off); + } + off += scnprintf(buf + off, buf_size - off, "BAR4 Split -\t\t%s\n", ndev->bar4_split ? "yes" : "no"); @@ -1487,7 +1490,7 @@ static int xeon_setup_b2b_mw(struct intel_ntb_dev *ndev, pdev = ndev_pdev(ndev); mmio = ndev->self_mmio; - if (ndev->b2b_idx >= ndev->mw_count) { + if (ndev->b2b_idx == UINT_MAX) { dev_dbg(ndev_dev(ndev), "not using b2b mw\n"); b2b_bar = 0; ndev->b2b_off = 0; @@ -1779,6 +1782,13 @@ static int xeon_init_ntb(struct intel_ntb_dev *ndev) else ndev->b2b_idx = b2b_mw_idx; + if (ndev->b2b_idx >= ndev->mw_count) { + dev_dbg(ndev_dev(ndev), + "b2b_mw_idx %d invalid for mw_count %u\n", + b2b_mw_idx, ndev->mw_count); + return -EINVAL; + } + dev_dbg(ndev_dev(ndev), "setting up b2b mw idx %d means %d\n", b2b_mw_idx, ndev->b2b_idx); @@ -2008,7 +2018,7 @@ static inline void ndev_init_struct(struct intel_ntb_dev *ndev, ndev->ntb.ops = &intel_ntb_ops; ndev->b2b_off = 0; - ndev->b2b_idx = INT_MAX; + ndev->b2b_idx = UINT_MAX; ndev->bar4_split = 0;