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			In the match() callback, the struct device_driver * should not be changed, so change the function callback to be a const *. This is one step of many towards making the driver core safe to have struct device_driver in read-only memory. Because the match() callback is in all busses, all busses are modified to handle this properly. This does entail switching some container_of() calls to container_of_const() to properly handle the constant *. For some busses, like PCI and USB and HV, the const * is cast away in the match callback as those busses do want to modify those structures at this point in time (they have a local lock in the driver structure.) That will have to be changed in the future if they wish to have their struct device * in read-only-memory. Cc: Rafael J. Wysocki <rafael@kernel.org> Reviewed-by: Alex Elder <elder@kernel.org> Acked-by: Sumit Garg <sumit.garg@linaro.org> Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			109 lines
		
	
	
	
		
			3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			109 lines
		
	
	
	
		
			3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *	TURBOchannel driver services.
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|  *
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|  *	Copyright (c) 2005  James Simmons
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|  *	Copyright (c) 2006  Maciej W. Rozycki
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|  *
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|  *	Loosely based on drivers/dio/dio-driver.c and
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|  *	drivers/pci/pci-driver.c.
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|  *
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|  *	This file is subject to the terms and conditions of the GNU
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|  *	General Public License.  See the file "COPYING" in the main
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|  *	directory of this archive for more details.
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|  */
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| 
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| #include <linux/init.h>
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| #include <linux/module.h>
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| #include <linux/tc.h>
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| 
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| /**
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|  * tc_register_driver - register a new TC driver
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|  * @drv: the driver structure to register
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|  *
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|  * Adds the driver structure to the list of registered drivers
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|  * Returns a negative value on error, otherwise 0.
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|  * If no error occurred, the driver remains registered even if
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|  * no device was claimed during registration.
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|  */
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| int tc_register_driver(struct tc_driver *tdrv)
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| {
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| 	return driver_register(&tdrv->driver);
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| }
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| EXPORT_SYMBOL(tc_register_driver);
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| 
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| /**
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|  * tc_unregister_driver - unregister a TC driver
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|  * @drv: the driver structure to unregister
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|  *
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|  * Deletes the driver structure from the list of registered TC drivers,
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|  * gives it a chance to clean up by calling its remove() function for
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|  * each device it was responsible for, and marks those devices as
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|  * driverless.
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|  */
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| void tc_unregister_driver(struct tc_driver *tdrv)
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| {
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| 	driver_unregister(&tdrv->driver);
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| }
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| EXPORT_SYMBOL(tc_unregister_driver);
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| 
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| /**
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|  * tc_match_device - tell if a TC device structure has a matching
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|  *                   TC device ID structure
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|  * @tdrv: the TC driver to earch for matching TC device ID strings
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|  * @tdev: the TC device structure to match against
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|  *
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|  * Used by a driver to check whether a TC device present in the
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|  * system is in its list of supported devices.  Returns the matching
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|  * tc_device_id structure or %NULL if there is no match.
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|  */
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| static const struct tc_device_id *tc_match_device(const struct tc_driver *tdrv,
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| 						  struct tc_dev *tdev)
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| {
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| 	const struct tc_device_id *id = tdrv->id_table;
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| 
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| 	if (id) {
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| 		while (id->name[0] || id->vendor[0]) {
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| 			if (strcmp(tdev->name, id->name) == 0 &&
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| 			    strcmp(tdev->vendor, id->vendor) == 0)
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| 				return id;
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| 			id++;
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| 		}
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| 	}
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| 	return NULL;
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| }
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| 
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| /**
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|  * tc_bus_match - Tell if a device structure has a matching
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|  *                TC device ID structure
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|  * @dev: the device structure to match against
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|  * @drv: the device driver to search for matching TC device ID strings
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|  *
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|  * Used by a driver to check whether a TC device present in the
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|  * system is in its list of supported devices.  Returns 1 if there
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|  * is a match or 0 otherwise.
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|  */
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| static int tc_bus_match(struct device *dev, const struct device_driver *drv)
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| {
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| 	struct tc_dev *tdev = to_tc_dev(dev);
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| 	const struct tc_driver *tdrv = to_tc_driver(drv);
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| 	const struct tc_device_id *id;
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| 
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| 	id = tc_match_device(tdrv, tdev);
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| 	if (id)
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| 		return 1;
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| 
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| 	return 0;
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| }
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| 
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| const struct bus_type tc_bus_type = {
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| 	.name	= "tc",
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| 	.match	= tc_bus_match,
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| };
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| EXPORT_SYMBOL(tc_bus_type);
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| 
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| static int __init tc_driver_init(void)
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| {
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| 	return bus_register(&tc_bus_type);
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| }
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| 
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| postcore_initcall(tc_driver_init);
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