PCI: hotplug: ensure a consistent return value in error case

Typically, the return value desired for the failure of a function with an
integer return value is a negative integer.  In these cases, the return
value is sometimes a negative integer and sometimes 0, due to a subsequent
initialization of the return variable within the loop.

A simplified version of the semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)

//<smpl>
@r exists@
identifier ret;
position p;
constant C;
expression e1,e3,e4;
statement S;
@@

ret = -C
... when != ret = e3
    when any
if@p (...) S
... when any
if (\(ret != 0\|ret < 0\|ret > 0\) || ...) { ... return ...; }
... when != ret = e3
    when any
*if@p (...)
{
  ... when != ret = e4
  return ret;
}
//</smpl>

[bhelgaas: squashed into one patch]
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Julia Lawall
2012-07-16 09:25:56 -06:00
committed by Bjorn Helgaas
parent cfaf025112
commit 83d0571073
4 changed files with 40 additions and 16 deletions

View File

@@ -252,7 +252,7 @@ static int __init init_slots(void)
struct slot *slot;
struct hotplug_slot *hotplug_slot;
struct hotplug_slot_info *info;
int retval = -ENOMEM;
int retval;
int i;
/*
@@ -261,17 +261,23 @@ static int __init init_slots(void)
*/
for (i = 0; i < num_slots; ++i) {
slot = kzalloc(sizeof(*slot), GFP_KERNEL);
if (!slot)
if (!slot) {
retval = -ENOMEM;
goto error;
}
hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
if (!hotplug_slot)
if (!hotplug_slot) {
retval = -ENOMEM;
goto error_slot;
}
slot->hotplug_slot = hotplug_slot;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info)
if (!info) {
retval = -ENOMEM;
goto error_hpslot;
}
hotplug_slot->info = info;
slot->number = i;