kernel/drivers/xen/xen-pciback/conf_space_quirks.c
2024-07-22 17:22:30 +08:00

143 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* PCI Backend - Handle special overlays for broken devices.
*
* Author: Ryan Wilson <hap9@epoch.ncsc.mil>
* Author: Chris Bookholt <hap10@epoch.ncsc.mil>
*/
#define dev_fmt(fmt) DRV_NAME ": " fmt
#include <linux/kernel.h>
#include <linux/pci.h>
#include "pciback.h"
#include "conf_space.h"
#include "conf_space_quirks.h"
LIST_HEAD(xen_pcibk_quirks);
static inline const struct pci_device_id *
match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)
{
if ((id->vendor == PCI_ANY_ID || id->vendor == dev->vendor) &&
(id->device == PCI_ANY_ID || id->device == dev->device) &&
(id->subvendor == PCI_ANY_ID ||
id->subvendor == dev->subsystem_vendor) &&
(id->subdevice == PCI_ANY_ID ||
id->subdevice == dev->subsystem_device) &&
!((id->class ^ dev->class) & id->class_mask))
return id;
return NULL;
}
static struct xen_pcibk_config_quirk *xen_pcibk_find_quirk(struct pci_dev *dev)
{
struct xen_pcibk_config_quirk *tmp_quirk;
list_for_each_entry(tmp_quirk, &xen_pcibk_quirks, quirks_list)
if (match_one_device(&tmp_quirk->devid, dev) != NULL)
goto out;
tmp_quirk = NULL;
dev_printk(KERN_DEBUG, &dev->dev,
"quirk didn't match any device known\n");
out:
return tmp_quirk;
}
static inline void register_quirk(struct xen_pcibk_config_quirk *quirk)
{
list_add_tail(&quirk->quirks_list, &xen_pcibk_quirks);
}
int xen_pcibk_field_is_dup(struct pci_dev *dev, unsigned int reg)
{
int ret = 0;
struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
struct config_field_entry *cfg_entry;
list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
if (OFFSET(cfg_entry) == reg) {
ret = 1;
break;
}
}
return ret;
}
int xen_pcibk_config_quirks_add_field(struct pci_dev *dev, struct config_field
*field)
{
int err = 0;
switch (field->size) {
case 1:
field->u.b.read = xen_pcibk_read_config_byte;
field->u.b.write = xen_pcibk_write_config_byte;
break;
case 2:
field->u.w.read = xen_pcibk_read_config_word;
field->u.w.write = xen_pcibk_write_config_word;
break;
case 4:
field->u.dw.read = xen_pcibk_read_config_dword;
field->u.dw.write = xen_pcibk_write_config_dword;
break;
default:
err = -EINVAL;
goto out;
}
xen_pcibk_config_add_field(dev, field);
out:
return err;
}
int xen_pcibk_config_quirks_init(struct pci_dev *dev)
{
struct xen_pcibk_config_quirk *quirk;
int ret = 0;
quirk = kzalloc(sizeof(*quirk), GFP_KERNEL);
if (!quirk) {
ret = -ENOMEM;
goto out;
}
quirk->devid.vendor = dev->vendor;
quirk->devid.device = dev->device;
quirk->devid.subvendor = dev->subsystem_vendor;
quirk->devid.subdevice = dev->subsystem_device;
quirk->devid.class = 0;
quirk->devid.class_mask = 0;
quirk->devid.driver_data = 0UL;
quirk->pdev = dev;
register_quirk(quirk);
out:
return ret;
}
void xen_pcibk_config_field_free(struct config_field *field)
{
kfree(field);
}
int xen_pcibk_config_quirk_release(struct pci_dev *dev)
{
struct xen_pcibk_config_quirk *quirk;
int ret = 0;
quirk = xen_pcibk_find_quirk(dev);
if (!quirk) {
ret = -ENXIO;
goto out;
}
list_del(&quirk->quirks_list);
kfree(quirk);
out:
return ret;
}