linux-stable/drivers/pci/hotplug/acpiphp_core.c
Rolf Eike Beer ac9e989187 PCI: Change memory allocation for acpiphp slots
Change memory allocation for acpiphp slots

Change the "struct slot" that acpiphp uses for managing it's slots to
directly contain the memory for the needed struct hotplug_slot_info and
the slot's name. This way we need only two memory allocations per slot
instead of four.

While we are at it: make_slot_name() is just a wrapper around snprintf()
knowing the right arguments to call it. Since the function makes just one
function call and is only called from one place I inlined it by hand.

Finally this fixes a possible bug waiting for someone to hit it. There were
two unused local variables in acpiphp_register_hotplug_slot(). gcc did not
find them because they were used in memory allocations with sizeof(*var).
They had the same types as the target of the allocation, but nevertheless
this was just weird.

Signed-off-by: Rolf Eike Beer <eike-hotplug@sf-tec.de>
Acked-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:36:59 -08:00

411 lines
11 KiB
C

/*
* ACPI PCI Hot Plug Controller Driver
*
* Copyright (C) 1995,2001 Compaq Computer Corporation
* Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (C) 2001 IBM Corp.
* Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
* Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
* Copyright (C) 2002,2003 NEC Corporation
* Copyright (C) 2003-2005 Matthew Wilcox (matthew.wilcox@hp.com)
* Copyright (C) 2003-2005 Hewlett Packard
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Send feedback to <kristen.c.accardi@intel.com>
*
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include "acpiphp.h"
#define MY_NAME "acpiphp"
static int debug;
int acpiphp_debug;
/* local variables */
static int num_slots;
static struct acpiphp_attention_info *attention_info;
#define DRIVER_VERSION "0.5"
#define DRIVER_AUTHOR "Greg Kroah-Hartman <gregkh@us.ibm.com>, Takayoshi Kochi <t-kochi@bq.jp.nec.com>, Matthew Wilcox <willy@hp.com>"
#define DRIVER_DESC "ACPI Hot Plug PCI Controller Driver"
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
module_param(debug, bool, 0644);
/* export the attention callback registration methods */
EXPORT_SYMBOL_GPL(acpiphp_register_attention);
EXPORT_SYMBOL_GPL(acpiphp_unregister_attention);
static int enable_slot (struct hotplug_slot *slot);
static int disable_slot (struct hotplug_slot *slot);
static int set_attention_status (struct hotplug_slot *slot, u8 value);
static int get_power_status (struct hotplug_slot *slot, u8 *value);
static int get_attention_status (struct hotplug_slot *slot, u8 *value);
static int get_address (struct hotplug_slot *slot, u32 *value);
static int get_latch_status (struct hotplug_slot *slot, u8 *value);
static int get_adapter_status (struct hotplug_slot *slot, u8 *value);
static struct hotplug_slot_ops acpi_hotplug_slot_ops = {
.owner = THIS_MODULE,
.enable_slot = enable_slot,
.disable_slot = disable_slot,
.set_attention_status = set_attention_status,
.get_power_status = get_power_status,
.get_attention_status = get_attention_status,
.get_latch_status = get_latch_status,
.get_adapter_status = get_adapter_status,
.get_address = get_address,
};
/**
* acpiphp_register_attention - set attention LED callback
* @info: must be completely filled with LED callbacks
*
* Description: this is used to register a hardware specific ACPI
* driver that manipulates the attention LED. All the fields in
* info must be set.
**/
int acpiphp_register_attention(struct acpiphp_attention_info *info)
{
int retval = -EINVAL;
if (info && info->owner && info->set_attn &&
info->get_attn && !attention_info) {
retval = 0;
attention_info = info;
}
return retval;
}
/**
* acpiphp_unregister_attention - unset attention LED callback
* @info: must match the pointer used to register
*
* Description: this is used to un-register a hardware specific acpi
* driver that manipulates the attention LED. The pointer to the
* info struct must be the same as the one used to set it.
**/
int acpiphp_unregister_attention(struct acpiphp_attention_info *info)
{
int retval = -EINVAL;
if (info && attention_info == info) {
attention_info = NULL;
retval = 0;
}
return retval;
}
/**
* enable_slot - power on and enable a slot
* @hotplug_slot: slot to enable
*
* Actual tasks are done in acpiphp_enable_slot()
*
*/
static int enable_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
/* enable the specified slot */
return acpiphp_enable_slot(slot->acpi_slot);
}
/**
* disable_slot - disable and power off a slot
* @hotplug_slot: slot to disable
*
* Actual tasks are done in acpiphp_disable_slot()
*
*/
static int disable_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
/* disable the specified slot */
return acpiphp_disable_slot(slot->acpi_slot);
}
/**
* set_attention_status - set attention LED
* @hotplug_slot: slot to set attention LED on
* @status: value to set attention LED to (0 or 1)
*
* attention status LED, so we use a callback that
* was registered with us. This allows hardware specific
* ACPI implementations to blink the light for us.
**/
static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
{
int retval = -ENODEV;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
if (attention_info && try_module_get(attention_info->owner)) {
retval = attention_info->set_attn(hotplug_slot, status);
module_put(attention_info->owner);
} else
attention_info = NULL;
return retval;
}
/**
* get_power_status - get power status of a slot
* @hotplug_slot: slot to get status
* @value: pointer to store status
*
* Some platforms may not implement _STA method properly.
* In that case, the value returned may not be reliable.
*
*/
static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
*value = acpiphp_get_power_status(slot->acpi_slot);
return 0;
}
/**
* get_attention_status - get attention LED status
* @hotplug_slot: slot to get status from
* @value: returns with value of attention LED
*
* ACPI doesn't have known method to determine the state
* of the attention status LED, so we use a callback that
* was registered with us. This allows hardware specific
* ACPI implementations to determine its state
**/
static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
int retval = -EINVAL;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
if (attention_info && try_module_get(attention_info->owner)) {
retval = attention_info->get_attn(hotplug_slot, value);
module_put(attention_info->owner);
} else
attention_info = NULL;
return retval;
}
/**
* get_latch_status - get latch status of a slot
* @hotplug_slot: slot to get status
* @value: pointer to store status
*
* ACPI doesn't provide any formal means to access latch status.
* Instead, we fake latch status from _STA
*
*/
static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
*value = acpiphp_get_latch_status(slot->acpi_slot);
return 0;
}
/**
* get_adapter_status - get adapter status of a slot
* @hotplug_slot: slot to get status
* @value: pointer to store status
*
* ACPI doesn't provide any formal means to access adapter status.
* Instead, we fake adapter status from _STA
*
*/
static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
struct slot *slot = hotplug_slot->private;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
*value = acpiphp_get_adapter_status(slot->acpi_slot);
return 0;
}
/**
* get_address - get pci address of a slot
* @hotplug_slot: slot to get status
* @value: pointer to struct pci_busdev (seg, bus, dev)
*/
static int get_address(struct hotplug_slot *hotplug_slot, u32 *value)
{
struct slot *slot = hotplug_slot->private;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
*value = acpiphp_get_address(slot->acpi_slot);
return 0;
}
static int __init init_acpi(void)
{
int retval;
/* initialize internal data structure etc. */
retval = acpiphp_glue_init();
/* read initial number of slots */
if (!retval) {
num_slots = acpiphp_get_num_slots();
if (num_slots == 0) {
acpiphp_glue_exit();
retval = -ENODEV;
}
}
return retval;
}
/**
* release_slot - free up the memory used by a slot
* @hotplug_slot: slot to free
*/
static void release_slot(struct hotplug_slot *hotplug_slot)
{
struct slot *slot = hotplug_slot->private;
dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
kfree(slot->hotplug_slot);
kfree(slot);
}
/* callback routine to initialize 'struct slot' for each slot */
int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
{
struct slot *slot;
int retval = -ENOMEM;
slot = kzalloc(sizeof(*slot), GFP_KERNEL);
if (!slot)
goto error;
slot->hotplug_slot = kzalloc(sizeof(*slot->hotplug_slot), GFP_KERNEL);
if (!slot->hotplug_slot)
goto error_slot;
slot->hotplug_slot->info = &slot->info;
slot->hotplug_slot->name = slot->name;
slot->hotplug_slot->private = slot;
slot->hotplug_slot->release = &release_slot;
slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
slot->acpi_slot = acpiphp_slot;
slot->hotplug_slot->info->power_status = acpiphp_get_power_status(slot->acpi_slot);
slot->hotplug_slot->info->attention_status = 0;
slot->hotplug_slot->info->latch_status = acpiphp_get_latch_status(slot->acpi_slot);
slot->hotplug_slot->info->adapter_status = acpiphp_get_adapter_status(slot->acpi_slot);
slot->hotplug_slot->info->max_bus_speed = PCI_SPEED_UNKNOWN;
slot->hotplug_slot->info->cur_bus_speed = PCI_SPEED_UNKNOWN;
acpiphp_slot->slot = slot;
snprintf(slot->name, sizeof(slot->name), "%u", slot->acpi_slot->sun);
retval = pci_hp_register(slot->hotplug_slot);
if (retval) {
err("pci_hp_register failed with error %d\n", retval);
goto error_hpslot;
}
info("Slot [%s] registered\n", slot->hotplug_slot->name);
return 0;
error_hpslot:
kfree(slot->hotplug_slot);
error_slot:
kfree(slot);
error:
return retval;
}
void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
{
struct slot *slot = acpiphp_slot->slot;
int retval = 0;
info ("Slot [%s] unregistered\n", slot->hotplug_slot->name);
retval = pci_hp_deregister(slot->hotplug_slot);
if (retval)
err("pci_hp_deregister failed with error %d\n", retval);
}
static int __init acpiphp_init(void)
{
info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
acpiphp_debug = debug;
/* read all the ACPI info from the system */
return init_acpi();
}
static void __exit acpiphp_exit(void)
{
/* deallocate internal data structures etc. */
acpiphp_glue_exit();
}
module_init(acpiphp_init);
module_exit(acpiphp_exit);