From 33ab349037db079aec7d60608fe4fb1114be6b91 Mon Sep 17 00:00:00 2001 From: Dennis Dalessandro Date: Wed, 2 Dec 2015 00:43:37 -0500 Subject: [PATCH] staging/rdma/hfi1: Reduce snoop locking scope in IOCTL handler. This patch avoids issues while calling into copy from/to user while holding the lock by only taking the lock when it is absolutely required. The only commands which require the snoop lock are: *Set Filter *Clear Filter *Clear Queue Reviewed-by: Mike Marciniszyn Signed-off-by: Dennis Dalessandro Signed-off-by: Ira Weiny Signed-off-by: Greg Kroah-Hartman --- drivers/staging/rdma/hfi1/diag.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/staging/rdma/hfi1/diag.c b/drivers/staging/rdma/hfi1/diag.c index ccc5aec..b0b7e28 100644 --- a/drivers/staging/rdma/hfi1/diag.c +++ b/drivers/staging/rdma/hfi1/diag.c @@ -1012,8 +1012,6 @@ static long hfi1_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) */ return -EINVAL; - spin_lock_irqsave(&dd->hfi1_snoop.snoop_lock, flags); - switch (cmd) { case HFI1_SNOOP_IOCSETLINKSTATE_EXTRA: memset(&link_info, 0, sizeof(link_info)); @@ -1130,11 +1128,14 @@ static long hfi1_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) case HFI1_SNOOP_IOCCLEARQUEUE: snoop_dbg("Clearing snoop queue"); + spin_lock_irqsave(&dd->hfi1_snoop.snoop_lock, flags); drain_snoop_list(&dd->hfi1_snoop.queue); + spin_unlock_irqrestore(&dd->hfi1_snoop.snoop_lock, flags); break; case HFI1_SNOOP_IOCCLEARFILTER: snoop_dbg("Clearing filter"); + spin_lock_irqsave(&dd->hfi1_snoop.snoop_lock, flags); if (dd->hfi1_snoop.filter_callback) { /* Drain packets first */ drain_snoop_list(&dd->hfi1_snoop.queue); @@ -1142,6 +1143,7 @@ static long hfi1_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) } kfree(dd->hfi1_snoop.filter_value); dd->hfi1_snoop.filter_value = NULL; + spin_unlock_irqrestore(&dd->hfi1_snoop.snoop_lock, flags); break; case HFI1_SNOOP_IOCSETFILTER: @@ -1178,13 +1180,14 @@ static long hfi1_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) break; } /* Drain packets first */ + spin_lock_irqsave(&dd->hfi1_snoop.snoop_lock, flags); drain_snoop_list(&dd->hfi1_snoop.queue); dd->hfi1_snoop.filter_callback = hfi1_filters[filter_cmd.opcode].filter; /* just in case we see back to back sets */ kfree(dd->hfi1_snoop.filter_value); dd->hfi1_snoop.filter_value = filter_value; - + spin_unlock_irqrestore(&dd->hfi1_snoop.snoop_lock, flags); break; case HFI1_SNOOP_IOCGETVERSION: value = SNOOP_CAPTURE_VERSION; @@ -1208,7 +1211,6 @@ static long hfi1_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) break; } done: - spin_unlock_irqrestore(&dd->hfi1_snoop.snoop_lock, flags); return ret; } -- 2.7.4