diff options
| -rw-r--r-- | drivers/base/bus.c | 38 | ||||
| -rw-r--r-- | drivers/pci/bus.c | 39 | ||||
| -rw-r--r-- | drivers/pci/search.c | 62 | ||||
| -rw-r--r-- | include/linux/device/bus.h | 3 | ||||
| -rw-r--r-- | include/linux/pci.h | 11 |
5 files changed, 145 insertions, 8 deletions
diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 5e75e1bce551..d19dae8f9d1b 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -334,6 +334,19 @@ static struct device *next_device(struct klist_iter *i) return dev; } +static struct device *prev_device(struct klist_iter *i) +{ + struct klist_node *n = klist_prev(i); + struct device *dev = NULL; + struct device_private *dev_prv; + + if (n) { + dev_prv = to_device_private_bus(n); + dev = dev_prv->device; + } + return dev; +} + /** * bus_for_each_dev - device iterator. * @bus: bus type. @@ -414,6 +427,31 @@ struct device *bus_find_device(const struct bus_type *bus, } EXPORT_SYMBOL_GPL(bus_find_device); +struct device *bus_find_device_reverse(const struct bus_type *bus, + struct device *start, const void *data, + device_match_t match) +{ + struct subsys_private *sp = bus_to_subsys(bus); + struct klist_iter i; + struct device *dev; + + if (!sp) + return NULL; + + klist_iter_init_node(&sp->klist_devices, &i, + (start ? &start->p->knode_bus : NULL)); + while ((dev = prev_device(&i))) { + if (match(dev, data)) { + get_device(dev); + break; + } + } + klist_iter_exit(&i); + subsys_put(sp); + return dev; +} +EXPORT_SYMBOL_GPL(bus_find_device_reverse); + static struct device_driver *next_driver(struct klist_iter *i) { struct klist_node *n = klist_next(i); diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index f26aec6ff588..b8b17f825bc0 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -8,6 +8,7 @@ */ #include <linux/module.h> #include <linux/kernel.h> +#include <linux/cleanup.h> #include <linux/pci.h> #include <linux/errno.h> #include <linux/ioport.h> @@ -432,6 +433,27 @@ static int __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void return ret; } +static int __pci_walk_bus_reverse(struct pci_bus *top, + int (*cb)(struct pci_dev *, void *), + void *userdata) +{ + struct pci_dev *dev; + int ret = 0; + + list_for_each_entry_reverse(dev, &top->devices, bus_list) { + if (dev->subordinate) { + ret = __pci_walk_bus_reverse(dev->subordinate, cb, + userdata); + if (ret) + break; + } + ret = cb(dev, userdata); + if (ret) + break; + } + return ret; +} + /** * pci_walk_bus - walk devices on/under bus, calling callback. * @top: bus whose devices should be walked @@ -453,6 +475,23 @@ void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void } EXPORT_SYMBOL_GPL(pci_walk_bus); +/** + * pci_walk_bus_reverse - walk devices on/under bus, calling callback. + * @top: bus whose devices should be walked + * @cb: callback to be called for each device found + * @userdata: arbitrary pointer to be passed to callback + * + * Same semantics as pci_walk_bus(), but walks the bus in reverse order. + */ +void pci_walk_bus_reverse(struct pci_bus *top, + int (*cb)(struct pci_dev *, void *), void *userdata) +{ + down_read(&pci_bus_sem); + __pci_walk_bus_reverse(top, cb, userdata); + up_read(&pci_bus_sem); +} +EXPORT_SYMBOL_GPL(pci_walk_bus_reverse); + void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata) { lockdep_assert_held(&pci_bus_sem); diff --git a/drivers/pci/search.c b/drivers/pci/search.c index 53840634fbfc..e6e84dc62e82 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -282,6 +282,45 @@ static struct pci_dev *pci_get_dev_by_id(const struct pci_device_id *id, return pdev; } +static struct pci_dev *pci_get_dev_by_id_reverse(const struct pci_device_id *id, + struct pci_dev *from) +{ + struct device *dev; + struct device *dev_start = NULL; + struct pci_dev *pdev = NULL; + + if (from) + dev_start = &from->dev; + dev = bus_find_device_reverse(&pci_bus_type, dev_start, (void *)id, + match_pci_dev_by_id); + if (dev) + pdev = to_pci_dev(dev); + pci_dev_put(from); + return pdev; +} + +enum pci_search_direction { + PCI_SEARCH_FORWARD, + PCI_SEARCH_REVERSE, +}; + +static struct pci_dev *__pci_get_subsys(unsigned int vendor, unsigned int device, + unsigned int ss_vendor, unsigned int ss_device, + struct pci_dev *from, enum pci_search_direction dir) +{ + struct pci_device_id id = { + .vendor = vendor, + .device = device, + .subvendor = ss_vendor, + .subdevice = ss_device, + }; + + if (dir == PCI_SEARCH_FORWARD) + return pci_get_dev_by_id(&id, from); + else + return pci_get_dev_by_id_reverse(&id, from); +} + /** * pci_get_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids @@ -302,14 +341,8 @@ struct pci_dev *pci_get_subsys(unsigned int vendor, unsigned int device, unsigned int ss_vendor, unsigned int ss_device, struct pci_dev *from) { - struct pci_device_id id = { - .vendor = vendor, - .device = device, - .subvendor = ss_vendor, - .subdevice = ss_device, - }; - - return pci_get_dev_by_id(&id, from); + return __pci_get_subsys(vendor, device, ss_vendor, ss_device, from, + PCI_SEARCH_FORWARD); } EXPORT_SYMBOL(pci_get_subsys); @@ -334,6 +367,19 @@ struct pci_dev *pci_get_device(unsigned int vendor, unsigned int device, } EXPORT_SYMBOL(pci_get_device); +/* + * Same semantics as pci_get_device(), except walks the PCI device list + * in reverse discovery order. + */ +struct pci_dev *pci_get_device_reverse(unsigned int vendor, + unsigned int device, + struct pci_dev *from) +{ + return __pci_get_subsys(vendor, device, PCI_ANY_ID, PCI_ANY_ID, from, + PCI_SEARCH_REVERSE); +} +EXPORT_SYMBOL(pci_get_device_reverse); + /** * pci_get_class - begin or continue searching for a PCI device by class * @class: search for a PCI device with this class designation diff --git a/include/linux/device/bus.h b/include/linux/device/bus.h index f5a56efd2bd6..99b1002b3e31 100644 --- a/include/linux/device/bus.h +++ b/include/linux/device/bus.h @@ -150,6 +150,9 @@ int bus_for_each_dev(const struct bus_type *bus, struct device *start, void *data, device_iter_t fn); struct device *bus_find_device(const struct bus_type *bus, struct device *start, const void *data, device_match_t match); +struct device *bus_find_device_reverse(const struct bus_type *bus, + struct device *start, const void *data, + device_match_t match); /** * bus_find_device_by_name - device iterator for locating a particular device * of a specific name. diff --git a/include/linux/pci.h b/include/linux/pci.h index 4402ca931124..b6a12a82be12 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -582,6 +582,8 @@ struct pci_dev *pci_alloc_dev(struct pci_bus *bus); #define to_pci_dev(n) container_of(n, struct pci_dev, dev) #define for_each_pci_dev(d) while ((d = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, d)) != NULL) +#define for_each_pci_dev_reverse(d) \ + while ((d = pci_get_device_reverse(PCI_ANY_ID, PCI_ANY_ID, d)) != NULL) static inline int pci_channel_offline(struct pci_dev *pdev) { @@ -1242,6 +1244,8 @@ u64 pci_get_dsn(struct pci_dev *dev); struct pci_dev *pci_get_device(unsigned int vendor, unsigned int device, struct pci_dev *from); +struct pci_dev *pci_get_device_reverse(unsigned int vendor, unsigned int device, + struct pci_dev *from); struct pci_dev *pci_get_subsys(unsigned int vendor, unsigned int device, unsigned int ss_vendor, unsigned int ss_device, struct pci_dev *from); @@ -1661,6 +1665,8 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata); +void pci_walk_bus_reverse(struct pci_bus *top, + int (*cb)(struct pci_dev *, void *), void *userdata); int pci_cfg_space_size(struct pci_dev *dev); unsigned char pci_bus_max_busnr(struct pci_bus *bus); resource_size_t pcibios_window_alignment(struct pci_bus *bus, @@ -2049,6 +2055,11 @@ static inline struct pci_dev *pci_get_device(unsigned int vendor, struct pci_dev *from) { return NULL; } +static inline struct pci_dev *pci_get_device_reverse(unsigned int vendor, + unsigned int device, + struct pci_dev *from) +{ return NULL; } + static inline struct pci_dev *pci_get_subsys(unsigned int vendor, unsigned int device, unsigned int ss_vendor, |