mirror of
https://github.com/torvalds/linux.git
synced 2024-12-20 18:11:47 +00:00
c4277e9ea7
If uio_register_device() fails in probe(), it breaks off initialization, deallocates all resources, but returns zero. The patch adds proper error code propagation. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
129 lines
3.2 KiB
C
129 lines
3.2 KiB
C
/* uio_pci_generic - generic UIO driver for PCI 2.3 devices
|
|
*
|
|
* Copyright (C) 2009 Red Hat, Inc.
|
|
* Author: Michael S. Tsirkin <mst@redhat.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2.
|
|
*
|
|
* Since the driver does not declare any device ids, you must allocate
|
|
* id and bind the device to the driver yourself. For example:
|
|
*
|
|
* # echo "8086 10f5" > /sys/bus/pci/drivers/uio_pci_generic/new_id
|
|
* # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/e1000e/unbind
|
|
* # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/uio_pci_generic/bind
|
|
* # ls -l /sys/bus/pci/devices/0000:00:19.0/driver
|
|
* .../0000:00:19.0/driver -> ../../../bus/pci/drivers/uio_pci_generic
|
|
*
|
|
* Driver won't bind to devices which do not support the Interrupt Disable Bit
|
|
* in the command register. All devices compliant to PCI 2.3 (circa 2002) and
|
|
* all compliant PCI Express devices should support this bit.
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/uio_driver.h>
|
|
|
|
#define DRIVER_VERSION "0.01.0"
|
|
#define DRIVER_AUTHOR "Michael S. Tsirkin <mst@redhat.com>"
|
|
#define DRIVER_DESC "Generic UIO driver for PCI 2.3 devices"
|
|
|
|
struct uio_pci_generic_dev {
|
|
struct uio_info info;
|
|
struct pci_dev *pdev;
|
|
};
|
|
|
|
static inline struct uio_pci_generic_dev *
|
|
to_uio_pci_generic_dev(struct uio_info *info)
|
|
{
|
|
return container_of(info, struct uio_pci_generic_dev, info);
|
|
}
|
|
|
|
/* Interrupt handler. Read/modify/write the command register to disable
|
|
* the interrupt. */
|
|
static irqreturn_t irqhandler(int irq, struct uio_info *info)
|
|
{
|
|
struct uio_pci_generic_dev *gdev = to_uio_pci_generic_dev(info);
|
|
|
|
if (!pci_check_and_mask_intx(gdev->pdev))
|
|
return IRQ_NONE;
|
|
|
|
/* UIO core will signal the user process. */
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int probe(struct pci_dev *pdev,
|
|
const struct pci_device_id *id)
|
|
{
|
|
struct uio_pci_generic_dev *gdev;
|
|
int err;
|
|
|
|
err = pci_enable_device(pdev);
|
|
if (err) {
|
|
dev_err(&pdev->dev, "%s: pci_enable_device failed: %d\n",
|
|
__func__, err);
|
|
return err;
|
|
}
|
|
|
|
if (!pdev->irq) {
|
|
dev_warn(&pdev->dev, "No IRQ assigned to device: "
|
|
"no support for interrupts?\n");
|
|
pci_disable_device(pdev);
|
|
return -ENODEV;
|
|
}
|
|
|
|
if (!pci_intx_mask_supported(pdev)) {
|
|
err = -ENODEV;
|
|
goto err_verify;
|
|
}
|
|
|
|
gdev = kzalloc(sizeof(struct uio_pci_generic_dev), GFP_KERNEL);
|
|
if (!gdev) {
|
|
err = -ENOMEM;
|
|
goto err_alloc;
|
|
}
|
|
|
|
gdev->info.name = "uio_pci_generic";
|
|
gdev->info.version = DRIVER_VERSION;
|
|
gdev->info.irq = pdev->irq;
|
|
gdev->info.irq_flags = IRQF_SHARED;
|
|
gdev->info.handler = irqhandler;
|
|
gdev->pdev = pdev;
|
|
|
|
err = uio_register_device(&pdev->dev, &gdev->info);
|
|
if (err)
|
|
goto err_register;
|
|
pci_set_drvdata(pdev, gdev);
|
|
|
|
return 0;
|
|
err_register:
|
|
kfree(gdev);
|
|
err_alloc:
|
|
err_verify:
|
|
pci_disable_device(pdev);
|
|
return err;
|
|
}
|
|
|
|
static void remove(struct pci_dev *pdev)
|
|
{
|
|
struct uio_pci_generic_dev *gdev = pci_get_drvdata(pdev);
|
|
|
|
uio_unregister_device(&gdev->info);
|
|
pci_disable_device(pdev);
|
|
kfree(gdev);
|
|
}
|
|
|
|
static struct pci_driver uio_pci_driver = {
|
|
.name = "uio_pci_generic",
|
|
.id_table = NULL, /* only dynamic id's */
|
|
.probe = probe,
|
|
.remove = remove,
|
|
};
|
|
|
|
module_pci_driver(uio_pci_driver);
|
|
MODULE_VERSION(DRIVER_VERSION);
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_AUTHOR(DRIVER_AUTHOR);
|
|
MODULE_DESCRIPTION(DRIVER_DESC);
|