[PATCH 5.6 124/194] pnp: Use list_for_each_entry() instead of open coding

Greg Kroah-Hartman
2020-05-18T18:06:31Z

From: Jason Gunthorpe <jgg@mellanox.com>

commit 01b2bafe57b19d9119413f138765ef57990921ce upstream.

Aside from good practice, this avoids a warning from gcc 10:

./include/linux/kernel.h:997:3: warning: array subscript -31 is outside array bounds of ‘struct list_head[1]’ [-Warray-bounds]
997 | ((type *)(__mptr - offsetof(type, member))); })
| ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/list.h:493:2: note: in expansion of macro ‘container_of’
493 | container_of(ptr, type, member)
| ^~~~~~~~~~~~
./include/linux/pnp.h:275:30: note: in expansion of macro ‘list_entry’
275 | #define global_to_pnp_dev(n) list_entry(n, struct pnp_dev, global_list)
| ^~~~~~~~~~
./include/linux/pnp.h:281:11: note: in expansion of macro ‘global_to_pnp_dev’
281 | (dev) != global_to_pnp_dev(&pnp_global); \
| ^~~~~~~~~~~~~~~~~
arch/x86/kernel/rtc.c:189:2: note: in expansion of macro ‘pnp_for_each_dev’
189 | pnp_for_each_dev(dev) {

Because the common code doesn't cast the starting list_head to the
containing struct.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
[ rjw: Whitespace adjustments ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
include/linux/pnp.h | 29 +++++++++--------------------
1 file changed, 9 insertions(+), 20 deletions(-)

--- a/include/linux/pnp.h
+++ b/include/linux/pnp.h
@@ -220,10 +220,8 @@ struct pnp_card {
#define global_to_pnp_card(n) list_entry(n, struct pnp_card, global_list)
#define protocol_to_pnp_card(n) list_entry(n, struct pnp_card, protocol_list)
#define to_pnp_card(n) container_of(n, struct pnp_card, dev)
-#define pnp_for_each_card(card) \
- for((card) = global_to_pnp_card(pnp_cards.next); \
- (card) != global_to_pnp_card(&pnp_cards); \
- (card) = global_to_pnp_card((card)->global_list.next))
+#define pnp_for_each_card(card) \
+ list_for_each_entry(card, &pnp_cards, global_list)

struct pnp_card_link {
struct pnp_card *card;
@@ -276,14 +274,9 @@ struct pnp_dev {
#define card_to_pnp_dev(n) list_entry(n, struct pnp_dev, card_list)
#define protocol_to_pnp_dev(n) list_entry(n, struct pnp_dev, protocol_list)
#define to_pnp_dev(n) container_of(n, struct pnp_dev, dev)
-#define pnp_for_each_dev(dev) \
- for((dev) = global_to_pnp_dev(pnp_global.next); \
- (dev) != global_to_pnp_dev(&pnp_global); \
- (dev) = global_to_pnp_dev((dev)->global_list.next))
-#define card_for_each_dev(card,dev) \
- for((dev) = card_to_pnp_dev((card)->devices.next); \
- (dev) != card_to_pnp_dev(&(card)->devices); \
- (dev) = card_to_pnp_dev((dev)->card_list.next))
+#define pnp_for_each_dev(dev) list_for_each_entry(dev, &pnp_global, global_list)
+#define card_for_each_dev(card, dev) \
+ list_for_each_entry(dev, &(card)->devices, card_list)
#define pnp_dev_name(dev) (dev)->name

static inline void *pnp_get_drvdata(struct pnp_dev *pdev)
@@ -437,14 +430,10 @@ struct pnp_protocol {
};

#define to_pnp_protocol(n) list_entry(n, struct pnp_protocol, protocol_list)
-#define protocol_for_each_card(protocol,card) \
- for((card) = protocol_to_pnp_card((protocol)->cards.next); \
- (card) != protocol_to_pnp_card(&(protocol)->cards); \
- (card) = protocol_to_pnp_card((card)->protocol_list.next))
-#define protocol_for_each_dev(protocol,dev) \
- for((dev) = protocol_to_pnp_dev((protocol)->devices.next); \
- (dev) != protocol_to_pnp_dev(&(protocol)->devices); \
- (dev) = protocol_to_pnp_dev((dev)->protocol_list.next))
+#define protocol_for_each_card(protocol, card) \
+ list_for_each_entry(card, &(protocol)->cards, protocol_list)
+#define protocol_for_each_dev(protocol, dev) \
+ list_for_each_entry(dev, &(protocol)->devices, protocol_list)

extern struct bus_type pnp_bus_type;