forked from mirrors/linux
		
	The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
        int stuff;
        struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
		
	
			
		
			
				
	
	
		
			135 lines
		
	
	
	
		
			4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			135 lines
		
	
	
	
		
			4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0-only */
 | 
						|
/*
 | 
						|
 * Enclosure Services
 | 
						|
 *
 | 
						|
 * Copyright (C) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
 | 
						|
 *
 | 
						|
**-----------------------------------------------------------------------------
 | 
						|
**
 | 
						|
**
 | 
						|
**-----------------------------------------------------------------------------
 | 
						|
*/
 | 
						|
#ifndef _LINUX_ENCLOSURE_H_
 | 
						|
#define _LINUX_ENCLOSURE_H_
 | 
						|
 | 
						|
#include <linux/device.h>
 | 
						|
#include <linux/list.h>
 | 
						|
 | 
						|
/* A few generic types ... taken from ses-2 */
 | 
						|
enum enclosure_component_type {
 | 
						|
	ENCLOSURE_COMPONENT_DEVICE = 0x01,
 | 
						|
	ENCLOSURE_COMPONENT_CONTROLLER_ELECTRONICS = 0x07,
 | 
						|
	ENCLOSURE_COMPONENT_SCSI_TARGET_PORT = 0x14,
 | 
						|
	ENCLOSURE_COMPONENT_SCSI_INITIATOR_PORT = 0x15,
 | 
						|
	ENCLOSURE_COMPONENT_ARRAY_DEVICE = 0x17,
 | 
						|
	ENCLOSURE_COMPONENT_SAS_EXPANDER = 0x18,
 | 
						|
};
 | 
						|
 | 
						|
/* ses-2 common element status */
 | 
						|
enum enclosure_status {
 | 
						|
	ENCLOSURE_STATUS_UNSUPPORTED = 0,
 | 
						|
	ENCLOSURE_STATUS_OK,
 | 
						|
	ENCLOSURE_STATUS_CRITICAL,
 | 
						|
	ENCLOSURE_STATUS_NON_CRITICAL,
 | 
						|
	ENCLOSURE_STATUS_UNRECOVERABLE,
 | 
						|
	ENCLOSURE_STATUS_NOT_INSTALLED,
 | 
						|
	ENCLOSURE_STATUS_UNKNOWN,
 | 
						|
	ENCLOSURE_STATUS_UNAVAILABLE,
 | 
						|
	/* last element for counting purposes */
 | 
						|
	ENCLOSURE_STATUS_MAX
 | 
						|
};
 | 
						|
 | 
						|
/* SFF-8485 activity light settings */
 | 
						|
enum enclosure_component_setting {
 | 
						|
	ENCLOSURE_SETTING_DISABLED = 0,
 | 
						|
	ENCLOSURE_SETTING_ENABLED = 1,
 | 
						|
	ENCLOSURE_SETTING_BLINK_A_ON_OFF = 2,
 | 
						|
	ENCLOSURE_SETTING_BLINK_A_OFF_ON = 3,
 | 
						|
	ENCLOSURE_SETTING_BLINK_B_ON_OFF = 6,
 | 
						|
	ENCLOSURE_SETTING_BLINK_B_OFF_ON = 7,
 | 
						|
};
 | 
						|
 | 
						|
struct enclosure_device;
 | 
						|
struct enclosure_component;
 | 
						|
struct enclosure_component_callbacks {
 | 
						|
	void (*get_status)(struct enclosure_device *,
 | 
						|
			     struct enclosure_component *);
 | 
						|
	int (*set_status)(struct enclosure_device *,
 | 
						|
			  struct enclosure_component *,
 | 
						|
			  enum enclosure_status);
 | 
						|
	void (*get_fault)(struct enclosure_device *,
 | 
						|
			  struct enclosure_component *);
 | 
						|
	int (*set_fault)(struct enclosure_device *,
 | 
						|
			 struct enclosure_component *,
 | 
						|
			 enum enclosure_component_setting);
 | 
						|
	void (*get_active)(struct enclosure_device *,
 | 
						|
			   struct enclosure_component *);
 | 
						|
	int (*set_active)(struct enclosure_device *,
 | 
						|
			  struct enclosure_component *,
 | 
						|
			  enum enclosure_component_setting);
 | 
						|
	void (*get_locate)(struct enclosure_device *,
 | 
						|
			   struct enclosure_component *);
 | 
						|
	int (*set_locate)(struct enclosure_device *,
 | 
						|
			  struct enclosure_component *,
 | 
						|
			  enum enclosure_component_setting);
 | 
						|
	void (*get_power_status)(struct enclosure_device *,
 | 
						|
				 struct enclosure_component *);
 | 
						|
	int (*set_power_status)(struct enclosure_device *,
 | 
						|
				struct enclosure_component *,
 | 
						|
				int);
 | 
						|
	int (*show_id)(struct enclosure_device *, char *buf);
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
struct enclosure_component {
 | 
						|
	void *scratch;
 | 
						|
	struct device cdev;
 | 
						|
	struct device *dev;
 | 
						|
	enum enclosure_component_type type;
 | 
						|
	int number;
 | 
						|
	int fault;
 | 
						|
	int active;
 | 
						|
	int locate;
 | 
						|
	int slot;
 | 
						|
	enum enclosure_status status;
 | 
						|
	int power_status;
 | 
						|
};
 | 
						|
 | 
						|
struct enclosure_device {
 | 
						|
	void *scratch;
 | 
						|
	struct list_head node;
 | 
						|
	struct device edev;
 | 
						|
	struct enclosure_component_callbacks *cb;
 | 
						|
	int components;
 | 
						|
	struct enclosure_component component[];
 | 
						|
};
 | 
						|
 | 
						|
static inline struct enclosure_device *
 | 
						|
to_enclosure_device(struct device *dev)
 | 
						|
{
 | 
						|
	return container_of(dev, struct enclosure_device, edev);
 | 
						|
}
 | 
						|
 | 
						|
static inline struct enclosure_component *
 | 
						|
to_enclosure_component(struct device *dev)
 | 
						|
{
 | 
						|
	return container_of(dev, struct enclosure_component, cdev);
 | 
						|
}
 | 
						|
 | 
						|
struct enclosure_device *
 | 
						|
enclosure_register(struct device *, const char *, int,
 | 
						|
		   struct enclosure_component_callbacks *);
 | 
						|
void enclosure_unregister(struct enclosure_device *);
 | 
						|
struct enclosure_component *
 | 
						|
enclosure_component_alloc(struct enclosure_device *, unsigned int,
 | 
						|
			  enum enclosure_component_type, const char *);
 | 
						|
int enclosure_component_register(struct enclosure_component *);
 | 
						|
int enclosure_add_device(struct enclosure_device *enclosure, int component,
 | 
						|
			 struct device *dev);
 | 
						|
int enclosure_remove_device(struct enclosure_device *, struct device *);
 | 
						|
struct enclosure_device *enclosure_find(struct device *dev,
 | 
						|
					struct enclosure_device *start);
 | 
						|
int enclosure_for_each_device(int (*fn)(struct enclosure_device *, void *),
 | 
						|
			      void *data);
 | 
						|
 | 
						|
#endif /* _LINUX_ENCLOSURE_H_ */
 |