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staging/rdma/hfi1: Reduce snoop locking scope in IOCTL handler.

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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 <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Dennis Dalessandro 2015-12-02 00:43:37 -05:00 • committed by Greg Kroah-Hartman
commit 33ab349037
1 changed files with 6 additions and 4 deletions
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10
drivers/staging/rdma/hfi1/diag.c
View file

@ -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;
}