driver-core: constify data for class_find_device()

All in-kernel users of class_find_device() don't really need mutable
data for match callback.

In two places (kernel/power/suspend_test.c, drivers/scsi/osd/osd_uld.c)
this patch changes match callbacks to use const search data.

The const is propagated to rtc_class_open() and power_supply_get_by_name()
parameters.

Note that there's a dev reference leak in suspend_test.c that's not
touched in this patch.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/base/class.c b/drivers/base/class.c
index 03243d4002fd5e995dd198447e98a9d2343fd89d..3ce8454713275a2bc7ab15a808e0c66dcfbece83 100644 (file)
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -420,8 +420,8 @@ EXPORT_SYMBOL_GPL(class_for_each_device);
  * code.  There's no locking restriction.
  */
 struct device *class_find_device(struct class *class, struct device *start,
-                                void *data,
-                                int (*match)(struct device *, void *))
+                                const void *data,
+                                int (*match)(struct device *, const void *))
 {
        struct class_dev_iter iter;
        struct device *dev;

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 27603a6c0a93ea63fc40f640c8b892fb5e0c618c..56536f4b0f6b9bfd6c3aa4aa603e43e75112de87 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1617,9 +1617,9 @@ struct device *device_create(struct class *class, struct device *parent,
 }
 EXPORT_SYMBOL_GPL(device_create);
 
-static int __match_devt(struct device *dev, void *data)
+static int __match_devt(struct device *dev, const void *data)
 {
-       dev_t *devt = data;
+       const dev_t *devt = data;
 
        return dev->devt == *devt;
 }

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 199fca15f2703ba4b32f749cf5ee41d78736b5ae..5359ca78130fe09376210395f964770562b70798 100644 (file)
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -806,7 +806,7 @@ fail_unlock:
 }
 EXPORT_SYMBOL_GPL(gpio_export);
 
-static int match_export(struct device *dev, void *data)
+static int match_export(struct device *dev, const void *data)
 {
        return dev_get_drvdata(dev) == data;
 }

diff --git a/drivers/isdn/mISDN/core.c b/drivers/isdn/mISDN/core.c
index 3e245712bba7e17a9f47e2060fc0dc4fdcd4b7ae..da30c5cb96096b6ff366c4473b9199ae20a72919 100644 (file)
--- a/drivers/isdn/mISDN/core.c
+++ b/drivers/isdn/mISDN/core.c
@@ -168,13 +168,13 @@ static struct class mISDN_class = {
 };
 
 static int
-_get_mdevice(struct device *dev, void *id)
+_get_mdevice(struct device *dev, const void *id)
 {
        struct mISDNdevice *mdev = dev_to_mISDN(dev);
 
        if (!mdev)
                return 0;
-       if (mdev->id != *(u_int *)id)
+       if (mdev->id != *(const u_int *)id)
                return 0;
        return 1;
 }

diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index 044b5326459fe807fc53e7af30de56c630c5cad3..dc920974204e6426610ac5f2fad3a7ba4bd1dd9c 100644 (file)
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -95,7 +95,7 @@ static struct class mdio_bus_class = {
 
 #if IS_ENABLED(CONFIG_OF_MDIO)
 /* Helper function for of_mdio_find_bus */
-static int of_mdio_bus_match(struct device *dev, void *mdio_bus_np)
+static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np)
 {
        return dev->of_node == mdio_bus_np;
 }

diff --git a/drivers/power/power_supply_core.c b/drivers/power/power_supply_core.c
index 8a7cfb3cc16694e7fdd4881d9bede20b7aaf4099..5deac432e2ae7b2025bc2e985ec5b6da6dff214d 100644 (file)
--- a/drivers/power/power_supply_core.c
+++ b/drivers/power/power_supply_core.c
@@ -141,7 +141,7 @@ int power_supply_set_battery_charged(struct power_supply *psy)
 }
 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
 
-static int power_supply_match_device_by_name(struct device *dev, void *data)
+static int power_supply_match_device_by_name(struct device *dev, const void *data)
 {
        const char *name = data;
        struct power_supply *psy = dev_get_drvdata(dev);
@@ -149,7 +149,7 @@ static int power_supply_match_device_by_name(struct device *dev, void *data)
        return strcmp(psy->name, name) == 0;
 }
 
-struct power_supply *power_supply_get_by_name(char *name)
+struct power_supply *power_supply_get_by_name(const char *name)
 {
        struct device *dev = class_find_device(power_supply_class, NULL, name,
                                        power_supply_match_device_by_name);

diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index 9592b936b71bca1987d19aceba0f6e8b20b165b9..42bd57da239de73a05c79c2f11ac129092aa9a19 100644 (file)
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -587,16 +587,16 @@ void rtc_update_irq(struct rtc_device *rtc,
 }
 EXPORT_SYMBOL_GPL(rtc_update_irq);
 
-static int __rtc_match(struct device *dev, void *data)
+static int __rtc_match(struct device *dev, const void *data)
 {
-       char *name = (char *)data;
+       const char *name = data;
 
        if (strcmp(dev_name(dev), name) == 0)
                return 1;
        return 0;
 }
 
-struct rtc_device *rtc_class_open(char *name)
+struct rtc_device *rtc_class_open(const char *name)
 {
        struct device *dev;
        struct rtc_device *rtc = NULL;

diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 593085a52275b33a3559228b9b7bf934748cc4d1..df0c3c71ea43977bf04355cbd4b5a0eaab54bbb7 100644 (file)
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -468,10 +468,10 @@ void scsi_unregister(struct Scsi_Host *shost)
 }
 EXPORT_SYMBOL(scsi_unregister);
 
-static int __scsi_host_match(struct device *dev, void *data)
+static int __scsi_host_match(struct device *dev, const void *data)
 {
        struct Scsi_Host *p;
-       unsigned short *hostnum = (unsigned short *)data;
+       const unsigned short *hostnum = data;
 
        p = class_to_shost(dev);
        return p->host_no == *hostnum;

diff --git a/drivers/scsi/osd/osd_uld.c b/drivers/scsi/osd/osd_uld.c
index 43754176a7b7efdacaaab1953a3a826ec1cdc53d..0fab6b5c7b8293da875bce94b5bdca9a9c97e41a 100644 (file)
--- a/drivers/scsi/osd/osd_uld.c
+++ b/drivers/scsi/osd/osd_uld.c
@@ -268,18 +268,11 @@ static inline bool _the_same_or_null(const u8 *a1, unsigned a1_len,
        return 0 == memcmp(a1, a2, a1_len);
 }
 
-struct find_oud_t {
-       const struct osd_dev_info *odi;
-       struct device *dev;
-       struct osd_uld_device *oud;
-} ;
-
-int _mach_odi(struct device *dev, void *find_data)
+static int _match_odi(struct device *dev, const void *find_data)
 {
        struct osd_uld_device *oud = container_of(dev, struct osd_uld_device,
                                                  class_dev);
-       struct find_oud_t *fot = find_data;
-       const struct osd_dev_info *odi = fot->odi;
+       const struct osd_dev_info *odi = find_data;
 
        if (_the_same_or_null(oud->odi.systemid, oud->odi.systemid_len,
                              odi->systemid, odi->systemid_len) &&
@@ -287,7 +280,6 @@ int _mach_odi(struct device *dev, void *find_data)
                              odi->osdname, odi->osdname_len)) {
                OSD_DEBUG("found device sysid_len=%d osdname=%d\n",
                          odi->systemid_len, odi->osdname_len);
-               fot->oud = oud;
                return 1;
        } else {
                return 0;
@@ -301,19 +293,19 @@ int _mach_odi(struct device *dev, void *find_data)
  */
 struct osd_dev *osduld_info_lookup(const struct osd_dev_info *odi)
 {
-       struct find_oud_t find = {.odi = odi};
-
-       find.dev = class_find_device(&osd_uld_class, NULL, &find, _mach_odi);
-       if (likely(find.dev)) {
+       struct device *dev = class_find_device(&osd_uld_class, NULL, odi, _match_odi);
+       if (likely(dev)) {
                struct osd_dev_handle *odh = kzalloc(sizeof(*odh), GFP_KERNEL);
+               struct osd_uld_device *oud = container_of(dev,
+                       struct osd_uld_device, class_dev);
 
                if (unlikely(!odh)) {
-                       put_device(find.dev);
+                       put_device(dev);
                        return ERR_PTR(-ENOMEM);
                }
 
-               odh->od = find.oud->od;
-               odh->oud = find.oud;
+               odh->od = oud->od;
+               odh->oud = oud;
 
                return &odh->od;
        }

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 31969f2e13ceff07e2304dd0cca84b27c655fa22..59d427bf08e20e8ac379afe51ddc0cb86001f2cc 100644 (file)
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -183,10 +183,10 @@ static struct attribute_group iscsi_endpoint_group = {
 
 #define ISCSI_MAX_EPID -1
 
-static int iscsi_match_epid(struct device *dev, void *data)
+static int iscsi_match_epid(struct device *dev, const void *data)
 {
        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
-       uint64_t *epid = (uint64_t *) data;
+       const uint64_t *epid = data;
 
        return *epid == ep->id;
 }

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 19ee901577da8d1649b975e9873b7a6c1e40029f..493ce4a71717544ee926bb42fa5a73ff52f5ca15 100644 (file)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1248,10 +1248,10 @@ int spi_master_resume(struct spi_master *master)
 }
 EXPORT_SYMBOL_GPL(spi_master_resume);
 
-static int __spi_master_match(struct device *dev, void *data)
+static int __spi_master_match(struct device *dev, const void *data)
 {
        struct spi_master *m;
-       u16 *bus_num = data;
+       const u16 *bus_num = data;
 
        m = container_of(dev, struct spi_master, dev);
        return m->bus_num == *bus_num;

diff --git a/drivers/uwb/lc-rc.c b/drivers/uwb/lc-rc.c
index 4d688c7508012b2f54629dfd8545059589c7d03f..3eca6ceb9844ffe85fffedfe1c3d566c09083b09 100644 (file)
--- a/drivers/uwb/lc-rc.c
+++ b/drivers/uwb/lc-rc.c
@@ -40,9 +40,9 @@
 
 #include "uwb-internal.h"
 
-static int uwb_rc_index_match(struct device *dev, void *data)
+static int uwb_rc_index_match(struct device *dev, const void *data)
 {
-       int *index = data;
+       const int *index = data;
        struct uwb_rc *rc = dev_get_drvdata(dev);
 
        if (rc->index == *index)
@@ -334,9 +334,9 @@ void uwb_rc_rm(struct uwb_rc *rc)
 }
 EXPORT_SYMBOL_GPL(uwb_rc_rm);
 
-static int find_rc_try_get(struct device *dev, void *data)
+static int find_rc_try_get(struct device *dev, const void *data)
 {
-       struct uwb_rc *target_rc = data;
+       const struct uwb_rc *target_rc = data;
        struct uwb_rc *rc = dev_get_drvdata(dev);
 
        if (rc == NULL) {
@@ -386,9 +386,9 @@ static inline struct uwb_rc *uwb_rc_get(struct uwb_rc *rc)
        return rc;
 }
 
-static int find_rc_grandpa(struct device *dev, void *data)
+static int find_rc_grandpa(struct device *dev, const void *data)
 {
-       struct device *grandpa_dev = data;
+       const struct device *grandpa_dev = data;
        struct uwb_rc *rc = dev_get_drvdata(dev);
 
        if (rc->uwb_dev.dev.parent->parent == grandpa_dev) {
@@ -419,7 +419,7 @@ struct uwb_rc *uwb_rc_get_by_grandpa(const struct device *grandpa_dev)
        struct device *dev;
        struct uwb_rc *rc = NULL;
 
-       dev = class_find_device(&uwb_rc_class, NULL, (void *)grandpa_dev,
+       dev = class_find_device(&uwb_rc_class, NULL, grandpa_dev,
                                find_rc_grandpa);
        if (dev)
                rc = dev_get_drvdata(dev);
@@ -432,9 +432,9 @@ EXPORT_SYMBOL_GPL(uwb_rc_get_by_grandpa);
  *
  * @returns the pointer to the radio controller, properly referenced
  */
-static int find_rc_dev(struct device *dev, void *data)
+static int find_rc_dev(struct device *dev, const void *data)
 {
-       struct uwb_dev_addr *addr = data;
+       const struct uwb_dev_addr *addr = data;
        struct uwb_rc *rc = dev_get_drvdata(dev);
 
        if (rc == NULL) {
@@ -453,8 +453,7 @@ struct uwb_rc *uwb_rc_get_by_dev(const struct uwb_dev_addr *addr)
        struct device *dev;
        struct uwb_rc *rc = NULL;
 
-       dev = class_find_device(&uwb_rc_class, NULL, (void *)addr,
-                               find_rc_dev);
+       dev = class_find_device(&uwb_rc_class, NULL, addr, find_rc_dev);
        if (dev)
                rc = dev_get_drvdata(dev);
 

diff --git a/include/linux/device.h b/include/linux/device.h
index 251f33b21ef940815a01951b907d670d815c587d..a089676084a5b0c4e2ded872b9793917690ae9ee 100644 (file)
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -395,8 +395,8 @@ extern int class_for_each_device(struct class *class, struct device *start,
                                 void *data,
                                 int (*fn)(struct device *dev, void *data));
 extern struct device *class_find_device(struct class *class,
-                                       struct device *start, void *data,
-                                       int (*match)(struct device *, void *));
+                                       struct device *start, const void *data,
+                                       int (*match)(struct device *, const void *));
 
 struct class_attribute {
        struct attribute attr;

diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index 1f0ab90aff00ccbfc5075d49225d9d56ef73e4c8..86ecaa679ded4448b685aa51be795f63fb3d53f4 100644 (file)
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -224,7 +224,7 @@ struct power_supply_info {
        int use_for_apm;
 };
 
-extern struct power_supply *power_supply_get_by_name(char *name);
+extern struct power_supply *power_supply_get_by_name(const char *name);
 extern void power_supply_changed(struct power_supply *psy);
 extern int power_supply_am_i_supplied(struct power_supply *psy);
 extern int power_supply_set_battery_charged(struct power_supply *psy);

diff --git a/include/linux/rtc.h b/include/linux/rtc.h
index 9531845c419f8329000b8927a341057bb2a64e6d..445fe6e7c6290a834f926a4191396e1d951449ec 100644 (file)
--- a/include/linux/rtc.h
+++ b/include/linux/rtc.h
@@ -148,7 +148,7 @@ extern int rtc_initialize_alarm(struct rtc_device *rtc,
 extern void rtc_update_irq(struct rtc_device *rtc,
                        unsigned long num, unsigned long events);
 
-extern struct rtc_device *rtc_class_open(char *name);
+extern struct rtc_device *rtc_class_open(const char *name);
 extern void rtc_class_close(struct rtc_device *rtc);
 
 extern int rtc_irq_register(struct rtc_device *rtc,

diff --git a/init/do_mounts.c b/init/do_mounts.c
index 1d1b6348f903c8e517567794765120d3dfa16d16..a2b49f2c1bd81c82fcf6766b5509b2341b8b98d6 100644 (file)
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -81,9 +81,9 @@ struct uuidcmp {
  *
  * Returns 1 if the device matches, and 0 otherwise.
  */
-static int match_dev_by_uuid(struct device *dev, void *data)
+static int match_dev_by_uuid(struct device *dev, const void *data)
 {
-       struct uuidcmp *cmp = data;
+       const struct uuidcmp *cmp = data;
        struct hd_struct *part = dev_to_part(dev);
 
        if (!part->info)

diff --git a/kernel/power/suspend_test.c b/kernel/power/suspend_test.c
index 25596e450ac723d7a9409cb304784224f5fe3990..9b2a1d58558da81bfa31137a4b075214761f7a81 100644 (file)
--- a/kernel/power/suspend_test.c
+++ b/kernel/power/suspend_test.c
@@ -112,7 +112,7 @@ static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state)
        rtc_set_alarm(rtc, &alm);
 }
 
-static int __init has_wakealarm(struct device *dev, void *name_ptr)
+static int __init has_wakealarm(struct device *dev, const void *data)
 {
        struct rtc_device *candidate = to_rtc_device(dev);
 
@@ -121,7 +121,6 @@ static int __init has_wakealarm(struct device *dev, void *name_ptr)
        if (!device_may_wakeup(candidate->dev.parent))
                return 0;
 
-       *(const char **)name_ptr = dev_name(dev);
        return 1;
 }
 
@@ -159,8 +158,8 @@ static int __init test_suspend(void)
        static char             warn_no_rtc[] __initdata =
                KERN_WARNING "PM: no wakealarm-capable RTC driver is ready\n";
 
-       char                    *pony = NULL;
        struct rtc_device       *rtc = NULL;
+       struct device           *dev;
 
        /* PM is initialized by now; is that state testable? */
        if (test_state == PM_SUSPEND_ON)
@@ -171,9 +170,9 @@ static int __init test_suspend(void)
        }
 
        /* RTCs have initialized by now too ... can we use one? */
-       class_find_device(rtc_class, NULL, &pony, has_wakealarm);
-       if (pony)
-               rtc = rtc_class_open(pony);
+       dev = class_find_device(rtc_class, NULL, NULL, has_wakealarm);
+       if (dev)
+               rtc = rtc_class_open(dev_name(dev));
        if (!rtc) {
                printk(warn_no_rtc);
                goto done;

diff --git a/net/ieee802154/wpan-class.c b/net/ieee802154/wpan-class.c
index 1627ef2e85229d524727af6c111e3f4aa6507d36..13571eae6baec862f06857a39c5a735ba0b9bfea 100644 (file)
--- a/net/ieee802154/wpan-class.c
+++ b/net/ieee802154/wpan-class.c
@@ -91,7 +91,7 @@ static struct class wpan_phy_class = {
 static DEFINE_MUTEX(wpan_phy_mutex);
 static int wpan_phy_idx;
 
-static int wpan_phy_match(struct device *dev, void *data)
+static int wpan_phy_match(struct device *dev, const void *data)
 {
        return !strcmp(dev_name(dev), (const char *)data);
 }
@@ -103,8 +103,7 @@ struct wpan_phy *wpan_phy_find(const char *str)
        if (WARN_ON(!str))
                return NULL;
 
-       dev = class_find_device(&wpan_phy_class, NULL,
-                       (void *)str, wpan_phy_match);
+       dev = class_find_device(&wpan_phy_class, NULL, str, wpan_phy_match);
        if (!dev)
                return NULL;
 

diff --git a/net/nfc/core.c b/net/nfc/core.c
index aa64ea441676a1ce9fc8c2417cc4487eaecf2cec..0f4a6de6f16183bac66baf5a5d7a4b8dd2710011 100644 (file)
--- a/net/nfc/core.c
+++ b/net/nfc/core.c
@@ -734,10 +734,10 @@ struct class nfc_class = {
 };
 EXPORT_SYMBOL(nfc_class);
 
-static int match_idx(struct device *d, void *data)
+static int match_idx(struct device *d, const void *data)
 {
        struct nfc_dev *dev = to_nfc_dev(d);
-       unsigned int *idx = data;
+       const unsigned int *idx = data;
 
        return dev->idx == *idx;
 }