PCI: introduce pci_slot

Currently, /sys/bus/pci/slots/ only exposes hotplug attributes when a
hotplug driver is loaded, but PCI slots have attributes such as address,
speed, width, etc.  that are not related to hotplug at all.

Introduce pci_slot as the primary data structure and kobject model.
Hotplug attributes described in hotplug_slot become a secondary
structure associated with the pci_slot.

This patch only creates the infrastructure that allows the separation of
PCI slot attributes and hotplug attributes.  In this patch, the PCI
hotplug core remains the only user of this infrastructure, and thus,
/sys/bus/pci/slots/ will still only become populated when a hotplug
driver is loaded.

A later patch in this series will add a second user of this new
infrastructure and demonstrate splitting the task of exposing pci_slot
attributes from hotplug_slot attributes.

  - Make pci_slot the primary sysfs entity. hotplug_slot becomes a
    subsidiary structure.
    o pci_create_slot() creates and registers a slot with the PCI core
    o pci_slot_add_hotplug() gives it hotplug capability

  - Change the prototype of pci_hp_register() to take the bus and
    slot number (on parent bus) as parameters.

  - Remove all the ->get_address methods since this functionality is
    now handled by pci_slot directly.

[achiang@hp.com: rpaphp-correctly-pci_hp_register-for-empty-pci-slots]
Tested-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: make headers_check happy]
[akpm@linux-foundation.org: nuther build fix]
[akpm@linux-foundation.org: fix typo in #include]
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Cc: Greg KH <greg@kroah.com>
Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 99 insertions, 159 deletions

diff --git a/drivers/pci/hotplug/pci_hotplug_core.c b/drivers/pci/hotplug/pci_hotplug_core.c
index a11021e8ce37..4df31f375197 100644
--- a/drivers/pci/hotplug/pci_hotplug_core.c
+++ b/drivers/pci/hotplug/pci_hotplug_core.c
@@ -40,6 +40,7 @@
 #include <linux/pci.h>
 #include <linux/pci_hotplug.h>
 #include <asm/uaccess.h>
+#include "../pci.h"
 
 #define MY_NAME	"pci_hotplug"
 
@@ -60,41 +61,7 @@ static int debug;
 //////////////////////////////////////////////////////////////////
 
 static LIST_HEAD(pci_hotplug_slot_list);
-
-struct kset *pci_hotplug_slots_kset;
-
-static ssize_t hotplug_slot_attr_show(struct kobject *kobj,
-		struct attribute *attr, char *buf)
-{
-	struct hotplug_slot *slot = to_hotplug_slot(kobj);
-	struct hotplug_slot_attribute *attribute = to_hotplug_attr(attr);
-	return attribute->show ? attribute->show(slot, buf) : -EIO;
-}
-
-static ssize_t hotplug_slot_attr_store(struct kobject *kobj,
-		struct attribute *attr, const char *buf, size_t len)
-{
-	struct hotplug_slot *slot = to_hotplug_slot(kobj);
-	struct hotplug_slot_attribute *attribute = to_hotplug_attr(attr);
-	return attribute->store ? attribute->store(slot, buf, len) : -EIO;
-}
-
-static struct sysfs_ops hotplug_slot_sysfs_ops = {
-	.show = hotplug_slot_attr_show,
-	.store = hotplug_slot_attr_store,
-};
-
-static void hotplug_slot_release(struct kobject *kobj)
-{
-	struct hotplug_slot *slot = to_hotplug_slot(kobj);
-	if (slot->release)
-		slot->release(slot);
-}
-
-static struct kobj_type hotplug_slot_ktype = {
-	.sysfs_ops = &hotplug_slot_sysfs_ops,
-	.release = &hotplug_slot_release,
-};
+static DEFINE_SPINLOCK(pci_hotplug_slot_list_lock);
 
 /* these strings match up with the values in pci_bus_speed */
 static char *pci_bus_speed_strings[] = {
@@ -149,16 +116,15 @@ GET_STATUS(power_status, u8)
 GET_STATUS(attention_status, u8)
 GET_STATUS(latch_status, u8)
 GET_STATUS(adapter_status, u8)
-GET_STATUS(address, u32)
 GET_STATUS(max_bus_speed, enum pci_bus_speed)
 GET_STATUS(cur_bus_speed, enum pci_bus_speed)
 
-static ssize_t power_read_file (struct hotplug_slot *slot, char *buf)
+static ssize_t power_read_file(struct pci_slot *slot, char *buf)
 {
 	int retval;
 	u8 value;
 
-	retval = get_power_status (slot, &value);
+	retval = get_power_status(slot->hotplug, &value);
 	if (retval)
 		goto exit;
 	retval = sprintf (buf, "%d\n", value);
@@ -166,9 +132,10 @@ exit:
 	return retval;
 }
 
-static ssize_t power_write_file (struct hotplug_slot *slot, const char *buf,
+static ssize_t power_write_file(struct pci_slot *pci_slot, const char *buf,
 		size_t count)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	unsigned long lpower;
 	u8 power;
 	int retval = 0;
@@ -204,29 +171,30 @@ exit:
 	return count;
 }
 
-static struct hotplug_slot_attribute hotplug_slot_attr_power = {
+static struct pci_slot_attribute hotplug_slot_attr_power = {
 	.attr = {.name = "power", .mode = S_IFREG | S_IRUGO | S_IWUSR},
 	.show = power_read_file,
 	.store = power_write_file
 };
 
-static ssize_t attention_read_file (struct hotplug_slot *slot, char *buf)
+static ssize_t attention_read_file(struct pci_slot *slot, char *buf)
 {
 	int retval;
 	u8 value;
 
-	retval = get_attention_status (slot, &value);
+	retval = get_attention_status(slot->hotplug, &value);
 	if (retval)
 		goto exit;
-	retval = sprintf (buf, "%d\n", value);
+	retval = sprintf(buf, "%d\n", value);
 
 exit:
 	return retval;
 }
 
-static ssize_t attention_write_file (struct hotplug_slot *slot, const char *buf,
+static ssize_t attention_write_file(struct pci_slot *slot, const char *buf,
 		size_t count)
 {
+	struct hotplug_slot_ops *ops = slot->hotplug->ops;
 	unsigned long lattention;
 	u8 attention;
 	int retval = 0;
@@ -235,13 +203,13 @@ static ssize_t attention_write_file (struct hotplug_slot *slot, const char *buf,
 	attention = (u8)(lattention & 0xff);
 	dbg (" - attention = %d\n", attention);
 
-	if (!try_module_get(slot->ops->owner)) {
+	if (!try_module_get(ops->owner)) {
 		retval = -ENODEV;
 		goto exit;
 	}
-	if (slot->ops->set_attention_status)
-		retval = slot->ops->set_attention_status(slot, attention);
-	module_put(slot->ops->owner);
+	if (ops->set_attention_status)
+		retval = ops->set_attention_status(slot->hotplug, attention);
+	module_put(ops->owner);
 
 exit:	
 	if (retval)
@@ -249,18 +217,18 @@ exit:
 	return count;
 }
 
-static struct hotplug_slot_attribute hotplug_slot_attr_attention = {
+static struct pci_slot_attribute hotplug_slot_attr_attention = {
 	.attr = {.name = "attention", .mode = S_IFREG | S_IRUGO | S_IWUSR},
 	.show = attention_read_file,
 	.store = attention_write_file
 };
 
-static ssize_t latch_read_file (struct hotplug_slot *slot, char *buf)
+static ssize_t latch_read_file(struct pci_slot *slot, char *buf)
 {
 	int retval;
 	u8 value;
 
-	retval = get_latch_status (slot, &value);
+	retval = get_latch_status(slot->hotplug, &value);
 	if (retval)
 		goto exit;
 	retval = sprintf (buf, "%d\n", value);
@@ -269,17 +237,17 @@ exit:
 	return retval;
 }
 
-static struct hotplug_slot_attribute hotplug_slot_attr_latch = {
+static struct pci_slot_attribute hotplug_slot_attr_latch = {
 	.attr = {.name = "latch", .mode = S_IFREG | S_IRUGO},
 	.show = latch_read_file,
 };
 
-static ssize_t presence_read_file (struct hotplug_slot *slot, char *buf)
+static ssize_t presence_read_file(struct pci_slot *slot, char *buf)
 {
 	int retval;
 	u8 value;
 
-	retval = get_adapter_status (slot, &value);
+	retval = get_adapter_status(slot->hotplug, &value);
 	if (retval)
 		goto exit;
 	retval = sprintf (buf, "%d\n", value);
@@ -288,42 +256,20 @@ exit:
 	return retval;
 }
 
-static struct hotplug_slot_attribute hotplug_slot_attr_presence = {
+static struct pci_slot_attribute hotplug_slot_attr_presence = {
 	.attr = {.name = "adapter", .mode = S_IFREG | S_IRUGO},
 	.show = presence_read_file,
 };
 
-static ssize_t address_read_file (struct hotplug_slot *slot, char *buf)
-{
-	int retval;
-	u32 address;
-
-	retval = get_address (slot, &address);
-	if (retval)
-		goto exit;
-	retval = sprintf (buf, "%04x:%02x:%02x\n",
-			  (address >> 16) & 0xffff,
-			  (address >> 8) & 0xff,
-			  address & 0xff);
-
-exit:
-	return retval;
-}
-
-static struct hotplug_slot_attribute hotplug_slot_attr_address = {
-	.attr = {.name = "address", .mode = S_IFREG | S_IRUGO},
-	.show = address_read_file,
-};
-
 static char *unknown_speed = "Unknown bus speed";
 
-static ssize_t max_bus_speed_read_file (struct hotplug_slot *slot, char *buf)
+static ssize_t max_bus_speed_read_file(struct pci_slot *slot, char *buf)
 {
 	char *speed_string;
 	int retval;
 	enum pci_bus_speed value;
 	
-	retval = get_max_bus_speed (slot, &value);
+	retval = get_max_bus_speed(slot->hotplug, &value);
 	if (retval)
 		goto exit;
 
@@ -338,18 +284,18 @@ exit:
 	return retval;
 }
 
-static struct hotplug_slot_attribute hotplug_slot_attr_max_bus_speed = {
+static struct pci_slot_attribute hotplug_slot_attr_max_bus_speed = {
 	.attr = {.name = "max_bus_speed", .mode = S_IFREG | S_IRUGO},
 	.show = max_bus_speed_read_file,
 };
 
-static ssize_t cur_bus_speed_read_file (struct hotplug_slot *slot, char *buf)
+static ssize_t cur_bus_speed_read_file(struct pci_slot *slot, char *buf)
 {
 	char *speed_string;
 	int retval;
 	enum pci_bus_speed value;
 
-	retval = get_cur_bus_speed (slot, &value);
+	retval = get_cur_bus_speed(slot->hotplug, &value);
 	if (retval)
 		goto exit;
 
@@ -364,14 +310,15 @@ exit:
 	return retval;
 }
 
-static struct hotplug_slot_attribute hotplug_slot_attr_cur_bus_speed = {
+static struct pci_slot_attribute hotplug_slot_attr_cur_bus_speed = {
 	.attr = {.name = "cur_bus_speed", .mode = S_IFREG | S_IRUGO},
 	.show = cur_bus_speed_read_file,
 };
 
-static ssize_t test_write_file (struct hotplug_slot *slot, const char *buf,
+static ssize_t test_write_file(struct pci_slot *pci_slot, const char *buf,
 		size_t count)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	unsigned long ltest;
 	u32 test;
 	int retval = 0;
@@ -394,13 +341,14 @@ exit:
 	return count;
 }
 
-static struct hotplug_slot_attribute hotplug_slot_attr_test = {
+static struct pci_slot_attribute hotplug_slot_attr_test = {
 	.attr = {.name = "test", .mode = S_IFREG | S_IRUGO | S_IWUSR},
 	.store = test_write_file
 };
 
-static int has_power_file (struct hotplug_slot *slot)
+static int has_power_file(struct pci_slot *pci_slot)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	if ((!slot) || (!slot->ops))
 		return -ENODEV;
 	if ((slot->ops->enable_slot) ||
@@ -410,8 +358,9 @@ static int has_power_file (struct hotplug_slot *slot)
 	return -ENOENT;
 }
 
-static int has_attention_file (struct hotplug_slot *slot)
+static int has_attention_file(struct pci_slot *pci_slot)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	if ((!slot) || (!slot->ops))
 		return -ENODEV;
 	if ((slot->ops->set_attention_status) ||
@@ -420,8 +369,9 @@ static int has_attention_file (struct hotplug_slot *slot)
 	return -ENOENT;
 }
 
-static int has_latch_file (struct hotplug_slot *slot)
+static int has_latch_file(struct pci_slot *pci_slot)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	if ((!slot) || (!slot->ops))
 		return -ENODEV;
 	if (slot->ops->get_latch_status)
@@ -429,8 +379,9 @@ static int has_latch_file (struct hotplug_slot *slot)
 	return -ENOENT;
 }
 
-static int has_adapter_file (struct hotplug_slot *slot)
+static int has_adapter_file(struct pci_slot *pci_slot)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	if ((!slot) || (!slot->ops))
 		return -ENODEV;
 	if (slot->ops->get_adapter_status)
@@ -438,17 +389,9 @@ static int has_adapter_file (struct hotplug_slot *slot)
 	return -ENOENT;
 }
 
-static int has_address_file (struct hotplug_slot *slot)
-{
-	if ((!slot) || (!slot->ops))
-		return -ENODEV;
-	if (slot->ops->get_address)
-		return 0;
-	return -ENOENT;
-}
-
-static int has_max_bus_speed_file (struct hotplug_slot *slot)
+static int has_max_bus_speed_file(struct pci_slot *pci_slot)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	if ((!slot) || (!slot->ops))
 		return -ENODEV;
 	if (slot->ops->get_max_bus_speed)
@@ -456,8 +399,9 @@ static int has_max_bus_speed_file (struct hotplug_slot *slot)
 	return -ENOENT;
 }
 
-static int has_cur_bus_speed_file (struct hotplug_slot *slot)
+static int has_cur_bus_speed_file(struct pci_slot *pci_slot)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	if ((!slot) || (!slot->ops))
 		return -ENODEV;
 	if (slot->ops->get_cur_bus_speed)
@@ -465,8 +409,9 @@ static int has_cur_bus_speed_file (struct hotplug_slot *slot)
 	return -ENOENT;
 }
 
-static int has_test_file (struct hotplug_slot *slot)
+static int has_test_file(struct pci_slot *pci_slot)
 {
+	struct hotplug_slot *slot = pci_slot->hotplug;
 	if ((!slot) || (!slot->ops))
 		return -ENODEV;
 	if (slot->ops->hardware_test)
@@ -474,7 +419,7 @@ static int has_test_file (struct hotplug_slot *slot)
 	return -ENOENT;
 }
 
-static int fs_add_slot (struct hotplug_slot *slot)
+static int fs_add_slot(struct pci_slot *slot)
 {
 	int retval = 0;
 
@@ -505,13 +450,6 @@ static int fs_add_slot (struct hotplug_slot *slot)
 			goto exit_adapter;
 	}
 
-	if (has_address_file(slot) == 0) {
-		retval = sysfs_create_file(&slot->kobj,
-					   &hotplug_slot_attr_address.attr);
-		if (retval)
-			goto exit_address;
-	}
-
 	if (has_max_bus_speed_file(slot) == 0) {
 		retval = sysfs_create_file(&slot->kobj,
 					   &hotplug_slot_attr_max_bus_speed.attr);
@@ -544,10 +482,6 @@ exit_cur_speed:
 		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_max_bus_speed.attr);
 
 exit_max_speed:
-	if (has_address_file(slot) == 0)
-		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_address.attr);
-
-exit_address:
 	if (has_adapter_file(slot) == 0)
 		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_presence.attr);
 
@@ -567,7 +501,7 @@ exit:
 	return retval;
 }
 
-static void fs_remove_slot (struct hotplug_slot *slot)
+static void fs_remove_slot(struct pci_slot *slot)
 {
 	if (has_power_file(slot) == 0)
 		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_power.attr);
@@ -581,9 +515,6 @@ static void fs_remove_slot (struct hotplug_slot *slot)
 	if (has_adapter_file(slot) == 0)
 		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_presence.attr);
 
-	if (has_address_file(slot) == 0)
-		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_address.attr);
-
 	if (has_max_bus_speed_file(slot) == 0)
 		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_max_bus_speed.attr);
 
@@ -599,12 +530,16 @@ static struct hotplug_slot *get_slot_from_name (const char *name)
 	struct hotplug_slot *slot;
 	struct list_head *tmp;
 
+	spin_lock(&pci_hotplug_slot_list_lock);
 	list_for_each (tmp, &pci_hotplug_slot_list) {
 		slot = list_entry (tmp, struct hotplug_slot, slot_list);
 		if (strcmp(slot->name, name) == 0)
-			return slot;
+			goto out;
 	}
-	return NULL;
+	slot = NULL;
+out:
+	spin_unlock(&pci_hotplug_slot_list_lock);
+	return slot;
 }
 
 /**
@@ -616,9 +551,10 @@ static struct hotplug_slot *get_slot_from_name (const char *name)
  *
  * Returns 0 if successful, anything else for an error.
  */
-int pci_hp_register (struct hotplug_slot *slot)
+int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr)
 {
 	int result;
+	struct pci_slot *pci_slot;
 	struct hotplug_slot *tmp;
 
 	if (slot == NULL)
@@ -636,19 +572,28 @@ int pci_hp_register (struct hotplug_slot *slot)
 	if (tmp)
 		return -EEXIST;
 
-	slot->kobj.kset = pci_hotplug_slots_kset;
-	result = kobject_init_and_add(&slot->kobj, &hotplug_slot_ktype, NULL,
-				      "%s", slot->name);
-	if (result) {
-		err("Unable to register kobject '%s'", slot->name);
-		return -EINVAL;
+	pci_slot = pci_create_slot(bus, slot_nr, slot->name);
+	if (IS_ERR(pci_slot))
+		return PTR_ERR(pci_slot);
+
+	if (pci_slot->hotplug) {
+		dbg("%s: already claimed\n", __func__);
+		pci_destroy_slot(pci_slot);
+		return -EBUSY;
 	}
 
-	list_add (&slot->slot_list, &pci_hotplug_slot_list);
+	slot->pci_slot = pci_slot;
+	pci_slot->hotplug = slot;
+
+	spin_lock(&pci_hotplug_slot_list_lock);
+	list_add(&slot->slot_list, &pci_hotplug_slot_list);
+	spin_unlock(&pci_hotplug_slot_list_lock);
+
+	result = fs_add_slot(pci_slot);
+	kobject_uevent(&pci_slot->kobj, KOBJ_ADD);
+	dbg("Added slot %s to the list\n", slot->name);
+
 
-	result = fs_add_slot (slot);
-	kobject_uevent(&slot->kobj, KOBJ_ADD);
-	dbg ("Added slot %s to the list\n", slot->name);
 	return result;
 }
 
@@ -661,22 +606,30 @@ int pci_hp_register (struct hotplug_slot *slot)
  *
  * Returns 0 if successful, anything else for an error.
  */
-int pci_hp_deregister (struct hotplug_slot *slot)
+int pci_hp_deregister(struct hotplug_slot *hotplug)
 {
 	struct hotplug_slot *temp;
+	struct pci_slot *slot;
 
-	if (slot == NULL)
+	if (!hotplug)
 		return -ENODEV;
 
-	temp = get_slot_from_name (slot->name);
-	if (temp != slot) {
+	temp = get_slot_from_name(hotplug->name);
+	if (temp != hotplug)
 		return -ENODEV;
-	}
-	list_del (&slot->slot_list);
 
-	fs_remove_slot (slot);
-	dbg ("Removed slot %s from the list\n", slot->name);
-	kobject_put(&slot->kobj);
+	spin_lock(&pci_hotplug_slot_list_lock);
+	list_del(&hotplug->slot_list);
+	spin_unlock(&pci_hotplug_slot_list_lock);
+
+	slot = hotplug->pci_slot;
+	fs_remove_slot(slot);
+	dbg("Removed slot %s from the list\n", hotplug->name);
+
+	hotplug->release(hotplug);
+	slot->hotplug = NULL;
+	pci_destroy_slot(slot);
+
 	return 0;
 }
 
@@ -690,13 +643,15 @@ int pci_hp_deregister (struct hotplug_slot *slot)
  *
  * Returns 0 if successful, anything else for an error.
  */
-int __must_check pci_hp_change_slot_info(struct hotplug_slot *slot,
+int __must_check pci_hp_change_slot_info(struct hotplug_slot *hotplug,
 					 struct hotplug_slot_info *info)
 {
-	if ((slot == NULL) || (info == NULL))
+	struct pci_slot *slot;
+	if (!hotplug || !info)
 		return -ENODEV;
+	slot = hotplug->pci_slot;
 
-	memcpy (slot->info, info, sizeof (struct hotplug_slot_info));
+	memcpy(hotplug->info, info, sizeof(struct hotplug_slot_info));
 
 	return 0;
 }
@@ -704,36 +659,22 @@ int __must_check pci_hp_change_slot_info(struct hotplug_slot *slot,
 static int __init pci_hotplug_init (void)
 {
 	int result;
-	struct kset *pci_bus_kset;
 
-	pci_bus_kset = bus_get_kset(&pci_bus_type);
-
-	pci_hotplug_slots_kset = kset_create_and_add("slots", NULL,
-						     &pci_bus_kset->kobj);
-	if (!pci_hotplug_slots_kset) {
-		result = -ENOMEM;
-		err("Register subsys error\n");
-		goto exit;
-	}
 	result = cpci_hotplug_init(debug);
 	if (result) {
 		err ("cpci_hotplug_init with error %d\n", result);
-		goto err_subsys;
+		goto err_cpci;
 	}
 
 	info (DRIVER_DESC " version: " DRIVER_VERSION "\n");
-	goto exit;
 
-err_subsys:
-	kset_unregister(pci_hotplug_slots_kset);
-exit:
+err_cpci:
 	return result;
 }
 
 static void __exit pci_hotplug_exit (void)
 {
 	cpci_hotplug_exit();
-	kset_unregister(pci_hotplug_slots_kset);
 }
 
 module_init(pci_hotplug_init);
@@ -745,7 +686,6 @@ MODULE_LICENSE("GPL");
 module_param(debug, bool, 0644);
 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
 
-EXPORT_SYMBOL_GPL(pci_hotplug_slots_kset);
 EXPORT_SYMBOL_GPL(pci_hp_register);
 EXPORT_SYMBOL_GPL(pci_hp_deregister);
 EXPORT_SYMBOL_GPL(pci_hp_change_slot_info);