Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a3aca3da authored by Kristian Høgsberg's avatar Kristian Høgsberg Committed by Stefan Richter
Browse files

firewire: Switch cdev code over to use register_chrdev and keep a list of devices. 



The old mechanism kept a struct cdev for each fw device, but fops->release
would reference this struct after the device got freed in some cases.

Signed-off-by: default avatarKristian Høgsberg <krh@redhat.com>
Signed-off-by: default avatarStefan Richter <stefanr@s5r6.in-berlin.de>
parent 344bbc4d

drivers/firewire/fw-device-cdev.c

+4 −1
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 
#include <linux/poll.h>

#include <linux/delay.h>

#include <linux/mm.h>

#include <linux/idr.h>

#include <linux/compat.h>

#include <asm/uaccess.h>

#include "fw-transaction.h"
@@ -103,7 +104,9 @@ static int fw_device_op_open(struct inode *inode, struct file *file) 
	struct client *client;

	unsigned long flags;



	device = container_of(inode->i_cdev, struct fw_device, cdev);

	device = fw_device_from_devt(inode->i_rdev);

	if (device == NULL)

		return -ENODEV;



	client = kzalloc(sizeof *client, GFP_KERNEL);

	if (client == NULL)

drivers/firewire/fw-device.c

+36 −20
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <linux/kthread.h>

#include <linux/device.h>

#include <linux/delay.h>

#include <linux/idr.h>

#include "fw-transaction.h"

#include "fw-topology.h"

#include "fw-device.h"
@@ -407,14 +408,31 @@ static int shutdown_unit(struct device *device, void *data) 
	return 0;

}



static DEFINE_IDR(fw_device_idr);

int fw_cdev_major;



struct fw_device *fw_device_from_devt(dev_t devt)

{

	struct fw_device *device;



	down_read(&fw_bus_type.subsys.rwsem);

	device = idr_find(&fw_device_idr, MINOR(devt));

	up_read(&fw_bus_type.subsys.rwsem);



	return device;

}



static void fw_device_shutdown(struct work_struct *work)

{

	struct fw_device *device =

		container_of(work, struct fw_device, work.work);

	int minor = MINOR(device->device.devt);



	down_write(&fw_bus_type.subsys.rwsem);

	idr_remove(&fw_device_idr, minor);

	up_write(&fw_bus_type.subsys.rwsem);



	device_remove_file(&device->device, &config_rom_attribute);

	cdev_del(&device->cdev);

	unregister_chrdev_region(device->device.devt, 1);

	device_for_each_child(&device->device, NULL, shutdown_unit);

	device_unregister(&device->device);

}
@@ -434,9 +452,9 @@ static void fw_device_shutdown(struct work_struct *work) 


static void fw_device_init(struct work_struct *work)

{

	static atomic_t serial = ATOMIC_INIT(-1);

	struct fw_device *device =

		container_of(work, struct fw_device, work.work);

	int minor, err;



	/* All failure paths here set node->data to NULL, so that we

	 * don't try to do device_for_each_child() on a kfree()'d
@@ -456,28 +474,24 @@ static void fw_device_init(struct work_struct *work) 
		return;

	}



	err = -ENOMEM;

	down_write(&fw_bus_type.subsys.rwsem);

	if (idr_pre_get(&fw_device_idr, GFP_KERNEL))

		err = idr_get_new(&fw_device_idr, device, &minor);

	up_write(&fw_bus_type.subsys.rwsem);

	if (err < 0)

		goto error;



	device->device.bus = &fw_bus_type;

	device->device.release = fw_device_release;

	device->device.parent = device->card->device;

	device->device.devt = MKDEV(fw_cdev_major, minor);

	snprintf(device->device.bus_id, sizeof device->device.bus_id,

		 "fw%d", atomic_inc_return(&serial));



	if (alloc_chrdev_region(&device->device.devt, 0, 1, "fw")) {

		fw_error("Failed to register char device region.\n");

		goto error;

	}



	cdev_init(&device->cdev, &fw_device_ops);

	device->cdev.owner = THIS_MODULE;

	kobject_set_name(&device->cdev.kobj, device->device.bus_id);

	if (cdev_add(&device->cdev, device->device.devt, 1)) {

		fw_error("Failed to register char device.\n");

		goto error;

	}

		 "fw%d", minor);



	if (device_add(&device->device)) {

		fw_error("Failed to add device.\n");

		goto error;

		goto error_with_cdev;

	}



	if (device_create_file(&device->device, &config_rom_attribute) < 0) {
@@ -513,9 +527,11 @@ static void fw_device_init(struct work_struct *work) 


 error_with_device:

	device_del(&device->device);

 error_with_cdev:

	down_write(&fw_bus_type.subsys.rwsem);

	idr_remove(&fw_device_idr, minor);

	up_write(&fw_bus_type.subsys.rwsem);

 error:

	cdev_del(&device->cdev);

	unregister_chrdev_region(device->device.devt, 1);

	put_device(&device->device);

}

drivers/firewire/fw-device.h

+4 −1
Original line number Diff line number Diff line
@@ -39,7 +39,7 @@ struct fw_device { 
	int generation;

	struct fw_card *card;

	struct device device;

	struct cdev cdev;

	struct list_head link;

	struct list_head client_list;

	__be32 *config_rom;

	size_t config_rom_length;
@@ -59,6 +59,9 @@ int fw_device_enable_phys_dma(struct fw_device *device); 


void fw_device_cdev_update(struct fw_device *device);



struct fw_device *fw_device_from_devt(dev_t devt);

extern int fw_cdev_major;



struct fw_unit {

	struct device device;

	u32 *directory;

drivers/firewire/fw-transaction.c

+7 −0
Original line number Diff line number Diff line
@@ -761,6 +761,12 @@ static int __init fw_core_init(void) 
	if (retval < 0)

		return retval;



	fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);

	if (fw_cdev_major < 0) {

		bus_unregister(&fw_bus_type);

		return fw_cdev_major;

	}



	/* Add the vendor textual descriptor. */

	retval = fw_core_add_descriptor(&vendor_id_descriptor);

	BUG_ON(retval < 0);
@@ -772,6 +778,7 @@ static int __init fw_core_init(void) 


static void __exit fw_core_cleanup(void)

{

	unregister_chrdev(fw_cdev_major, "firewire");

	bus_unregister(&fw_bus_type);

}