kernel-fxtec-pro1x/include/linux/ipmi_smi.h
Corey Minyard f9d405a4bd ipmi: Don't allow device module unload when in use
[ Upstream commit cbb79863fc3175ed5ac506465948b02a893a8235 ]

If something has the IPMI driver open, don't allow the device
module to be unloaded.  Before it would unload and the user would
get errors on use.

This change is made on user request, and it makes it consistent
with the I2C driver, which has the same behavior.

It does change things a little bit with respect to kernel users.
If the ACPI or IPMI watchdog (or any other kernel user) has
created a user, then the device module cannot be unloaded.  Before
it could be unloaded,

This does not affect hot-plug.  If the device goes away (it's on
something removable that is removed or is hot-removed via sysfs)
then it still behaves as it did before.

Reported-by: tony camuso <tcamuso@redhat.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Tested-by: tony camuso <tcamuso@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-31 16:35:23 +01:00

247 lines
7.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* ipmi_smi.h
*
* MontaVista IPMI system management interface
*
* Author: MontaVista Software, Inc.
* Corey Minyard <minyard@mvista.com>
* source@mvista.com
*
* Copyright 2002 MontaVista Software Inc.
*
*/
#ifndef __LINUX_IPMI_SMI_H
#define __LINUX_IPMI_SMI_H
#include <linux/ipmi_msgdefs.h>
#include <linux/proc_fs.h>
#include <linux/platform_device.h>
#include <linux/ipmi.h>
struct device;
/*
* This files describes the interface for IPMI system management interface
* drivers to bind into the IPMI message handler.
*/
/* Structure for the low-level drivers. */
typedef struct ipmi_smi *ipmi_smi_t;
/*
* Messages to/from the lower layer. The smi interface will take one
* of these to send. After the send has occurred and a response has
* been received, it will report this same data structure back up to
* the upper layer. If an error occurs, it should fill in the
* response with an error code in the completion code location. When
* asynchronous data is received, one of these is allocated, the
* data_size is set to zero and the response holds the data from the
* get message or get event command that the interface initiated.
* Note that it is the interfaces responsibility to detect
* asynchronous data and messages and request them from the
* interface.
*/
struct ipmi_smi_msg {
struct list_head link;
long msgid;
void *user_data;
int data_size;
unsigned char data[IPMI_MAX_MSG_LENGTH];
int rsp_size;
unsigned char rsp[IPMI_MAX_MSG_LENGTH];
/* Will be called when the system is done with the message
(presumably to free it). */
void (*done)(struct ipmi_smi_msg *msg);
};
struct ipmi_smi_handlers {
struct module *owner;
/*
* The low-level interface cannot start sending messages to
* the upper layer until this function is called. This may
* not be NULL, the lower layer must take the interface from
* this call.
*/
int (*start_processing)(void *send_info,
struct ipmi_smi *new_intf);
/*
* When called, the low-level interface should disable all
* processing, it should be complete shut down when it returns.
*/
void (*shutdown)(void *send_info);
/*
* Get the detailed private info of the low level interface and store
* it into the structure of ipmi_smi_data. For example: the
* ACPI device handle will be returned for the pnp_acpi IPMI device.
*/
int (*get_smi_info)(void *send_info, struct ipmi_smi_info *data);
/*
* Called to enqueue an SMI message to be sent. This
* operation is not allowed to fail. If an error occurs, it
* should report back the error in a received message. It may
* do this in the current call context, since no write locks
* are held when this is run. Message are delivered one at
* a time by the message handler, a new message will not be
* delivered until the previous message is returned.
*/
void (*sender)(void *send_info,
struct ipmi_smi_msg *msg);
/*
* Called by the upper layer to request that we try to get
* events from the BMC we are attached to.
*/
void (*request_events)(void *send_info);
/*
* Called by the upper layer when some user requires that the
* interface watch for events, received messages, watchdog
* pretimeouts, or not. Used by the SMI to know if it should
* watch for these. This may be NULL if the SMI does not
* implement it.
*/
void (*set_need_watch)(void *send_info, bool enable);
/*
* Called when flushing all pending messages.
*/
void (*flush_messages)(void *send_info);
/*
* Called when the interface should go into "run to
* completion" mode. If this call sets the value to true, the
* interface should make sure that all messages are flushed
* out and that none are pending, and any new requests are run
* to completion immediately.
*/
void (*set_run_to_completion)(void *send_info, bool run_to_completion);
/*
* Called to poll for work to do. This is so upper layers can
* poll for operations during things like crash dumps.
*/
void (*poll)(void *send_info);
/*
* Enable/disable firmware maintenance mode. Note that this
* is *not* the modes defined, this is simply an on/off
* setting. The message handler does the mode handling. Note
* that this is called from interrupt context, so it cannot
* block.
*/
void (*set_maintenance_mode)(void *send_info, bool enable);
};
struct ipmi_device_id {
unsigned char device_id;
unsigned char device_revision;
unsigned char firmware_revision_1;
unsigned char firmware_revision_2;
unsigned char ipmi_version;
unsigned char additional_device_support;
unsigned int manufacturer_id;
unsigned int product_id;
unsigned char aux_firmware_revision[4];
unsigned int aux_firmware_revision_set : 1;
};
#define ipmi_version_major(v) ((v)->ipmi_version & 0xf)
#define ipmi_version_minor(v) ((v)->ipmi_version >> 4)
/*
* Take a pointer to an IPMI response and extract device id information from
* it. @netfn is in the IPMI_NETFN_ format, so may need to be shifted from
* a SI response.
*/
static inline int ipmi_demangle_device_id(uint8_t netfn, uint8_t cmd,
const unsigned char *data,
unsigned int data_len,
struct ipmi_device_id *id)
{
if (data_len < 7)
return -EINVAL;
if (netfn != IPMI_NETFN_APP_RESPONSE || cmd != IPMI_GET_DEVICE_ID_CMD)
/* Strange, didn't get the response we expected. */
return -EINVAL;
if (data[0] != 0)
/* That's odd, it shouldn't be able to fail. */
return -EINVAL;
data++;
data_len--;
id->device_id = data[0];
id->device_revision = data[1];
id->firmware_revision_1 = data[2];
id->firmware_revision_2 = data[3];
id->ipmi_version = data[4];
id->additional_device_support = data[5];
if (data_len >= 11) {
id->manufacturer_id = (data[6] | (data[7] << 8) |
(data[8] << 16));
id->product_id = data[9] | (data[10] << 8);
} else {
id->manufacturer_id = 0;
id->product_id = 0;
}
if (data_len >= 15) {
memcpy(id->aux_firmware_revision, data+11, 4);
id->aux_firmware_revision_set = 1;
} else
id->aux_firmware_revision_set = 0;
return 0;
}
/*
* Add a low-level interface to the IPMI driver. Note that if the
* interface doesn't know its slave address, it should pass in zero.
* The low-level interface should not deliver any messages to the
* upper layer until the start_processing() function in the handlers
* is called, and the lower layer must get the interface from that
* call.
*/
int ipmi_add_smi(struct module *owner,
const struct ipmi_smi_handlers *handlers,
void *send_info,
struct device *dev,
unsigned char slave_addr);
#define ipmi_register_smi(handlers, send_info, dev, slave_addr) \
ipmi_add_smi(THIS_MODULE, handlers, send_info, dev, slave_addr)
/*
* Remove a low-level interface from the IPMI driver. This will
* return an error if the interface is still in use by a user.
*/
void ipmi_unregister_smi(struct ipmi_smi *intf);
/*
* The lower layer reports received messages through this interface.
* The data_size should be zero if this is an asynchronous message. If
* the lower layer gets an error sending a message, it should format
* an error response in the message response.
*/
void ipmi_smi_msg_received(struct ipmi_smi *intf,
struct ipmi_smi_msg *msg);
/* The lower layer received a watchdog pre-timeout on interface. */
void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf);
struct ipmi_smi_msg *ipmi_alloc_smi_msg(void);
static inline void ipmi_free_smi_msg(struct ipmi_smi_msg *msg)
{
msg->done(msg);
}
#endif /* __LINUX_IPMI_SMI_H */