scsi: remove the old scsi_module.c initialization model
After more than 15 years all users of this legacy interface are finally gone. Rest in peace! Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
parent
616434e2aa
commit
83c9f08e6c
|
@ -154,12 +154,6 @@ lists).
|
|||
.. kernel-doc:: drivers/scsi/scsi_lib_dma.c
|
||||
:export:
|
||||
|
||||
drivers/scsi/scsi_module.c
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
The file drivers/scsi/scsi_module.c contains legacy support for
|
||||
old-style host templates. It should never be used by any new driver.
|
||||
|
||||
drivers/scsi/scsi_proc.c
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
|
|
|
@ -114,9 +114,7 @@ called "xxx" could be defined as
|
|||
"static int xxx_slave_alloc(struct scsi_device * sdev) { /* code */ }"
|
||||
|
||||
** the scsi_host_alloc() function is a replacement for the rather vaguely
|
||||
named scsi_register() function in most situations. The scsi_register()
|
||||
and scsi_unregister() functions remain to support legacy LLDs that use
|
||||
the passive initialization model.
|
||||
named scsi_register() function in most situations.
|
||||
|
||||
|
||||
Hotplug initialization model
|
||||
|
@ -228,79 +226,6 @@ slave_configure() callbacks). Such instances are "owned" by the mid-level.
|
|||
struct scsi_device instances are freed after slave_destroy().
|
||||
|
||||
|
||||
Passive initialization model
|
||||
============================
|
||||
These older LLDs include a file called "scsi_module.c" [yes the ".c" is a
|
||||
little surprising] in their source code. For that file to work an
|
||||
instance of struct scsi_host_template with the name "driver_template"
|
||||
needs to be defined. Here is a typical code sequence used in this model:
|
||||
static struct scsi_host_template driver_template = {
|
||||
...
|
||||
};
|
||||
#include "scsi_module.c"
|
||||
|
||||
The scsi_module.c file contains two functions:
|
||||
- init_this_scsi_driver() which is executed when the LLD is
|
||||
initialized (i.e. boot time or module load time)
|
||||
- exit_this_scsi_driver() which is executed when the LLD is shut
|
||||
down (i.e. module unload time)
|
||||
Note: since these functions are tagged with __init and __exit qualifiers
|
||||
an LLD should not call them explicitly (since the kernel does that).
|
||||
|
||||
Here is an example of an initialization sequence when two hosts are
|
||||
detected (so detect() returns 2) and the SCSI bus scan on each host
|
||||
finds 1 SCSI device (and a second device does not respond).
|
||||
|
||||
LLD mid level LLD
|
||||
===----------------------=========-----------------===------
|
||||
init_this_scsi_driver() ----+
|
||||
|
|
||||
detect() -----------------+
|
||||
| |
|
||||
| scsi_register()
|
||||
| scsi_register()
|
||||
|
|
||||
slave_alloc()
|
||||
slave_configure() --> scsi_change_queue_depth()
|
||||
slave_alloc() ***
|
||||
slave_destroy() ***
|
||||
|
|
||||
slave_alloc()
|
||||
slave_configure()
|
||||
slave_alloc() ***
|
||||
slave_destroy() ***
|
||||
------------------------------------------------------------
|
||||
|
||||
The mid level invokes scsi_change_queue_depth() with "cmd_per_lun" for that
|
||||
host as the queue length. These settings can be overridden by a
|
||||
slave_configure() supplied by the LLD.
|
||||
|
||||
*** For scsi devices that the mid level tries to scan but do not
|
||||
respond, a slave_alloc(), slave_destroy() pair is called.
|
||||
|
||||
Here is an LLD shutdown sequence:
|
||||
|
||||
LLD mid level LLD
|
||||
===----------------------=========-----------------===------
|
||||
exit_this_scsi_driver() ----+
|
||||
|
|
||||
slave_destroy()
|
||||
release() --> scsi_unregister()
|
||||
|
|
||||
slave_destroy()
|
||||
release() --> scsi_unregister()
|
||||
------------------------------------------------------------
|
||||
|
||||
An LLD need not define slave_destroy() (i.e. it is optional).
|
||||
|
||||
The shortcoming of the "passive initialization model" is that host
|
||||
registration and de-registration are (typically) tied to LLD initialization
|
||||
and shutdown. Once the LLD is initialized then a new host that appears
|
||||
(e.g. via hotplugging) cannot easily be added without a redundant
|
||||
driver shutdown and re-initialization. It may be possible to write an LLD
|
||||
that uses both initialization models.
|
||||
|
||||
|
||||
Reference Counting
|
||||
==================
|
||||
The Scsi_Host structure has had reference counting infrastructure added.
|
||||
|
@ -738,7 +663,6 @@ The interface functions are listed below in alphabetical order.
|
|||
|
||||
Summary:
|
||||
bios_param - fetch head, sector, cylinder info for a disk
|
||||
detect - detects HBAs this driver wants to control
|
||||
eh_timed_out - notify the host that a command timer expired
|
||||
eh_abort_handler - abort given command
|
||||
eh_bus_reset_handler - issue SCSI bus reset
|
||||
|
@ -748,7 +672,6 @@ Summary:
|
|||
ioctl - driver can respond to ioctls
|
||||
proc_info - supports /proc/scsi/{driver_name}/{host_no}
|
||||
queuecommand - queue scsi command, invoke 'done' on completion
|
||||
release - release all resources associated with given host
|
||||
slave_alloc - prior to any commands being sent to a new device
|
||||
slave_configure - driver fine tuning for given device after attach
|
||||
slave_destroy - given device is about to be shut down
|
||||
|
@ -784,28 +707,6 @@ Details:
|
|||
sector_t capacity, int params[3])
|
||||
|
||||
|
||||
/**
|
||||
* detect - detects HBAs this driver wants to control
|
||||
* @shtp: host template for this driver.
|
||||
*
|
||||
* Returns number of hosts this driver wants to control. 0 means no
|
||||
* suitable hosts found.
|
||||
*
|
||||
* Locks: none held
|
||||
*
|
||||
* Calling context: process [invoked from init_this_scsi_driver()]
|
||||
*
|
||||
* Notes: First function called from the SCSI mid level on this
|
||||
* driver. Upper level drivers (e.g. sd) may not (yet) be present.
|
||||
* For each host found, this method should call scsi_register()
|
||||
* [see hosts.c].
|
||||
*
|
||||
* Defined in: LLD (required if "passive initialization mode" is used,
|
||||
* not invoked in "hotplug initialization mode")
|
||||
**/
|
||||
int detect(struct scsi_host_template * shtp)
|
||||
|
||||
|
||||
/**
|
||||
* eh_timed_out - The timer for the command has just fired
|
||||
* @scp: identifies command timing out
|
||||
|
@ -1073,27 +974,6 @@ Details:
|
|||
int queuecommand(struct Scsi_Host *shost, struct scsi_cmnd * scp)
|
||||
|
||||
|
||||
/**
|
||||
* release - release all resources associated with given host
|
||||
* @shp: host to be released.
|
||||
*
|
||||
* Return value ignored (could soon be a function returning void).
|
||||
*
|
||||
* Locks: none held
|
||||
*
|
||||
* Calling context: process
|
||||
*
|
||||
* Notes: Invoked from scsi_module.c's exit_this_scsi_driver().
|
||||
* LLD's implementation of this function should call
|
||||
* scsi_unregister(shp) prior to returning.
|
||||
* Only needed for old-style host templates.
|
||||
*
|
||||
* Defined in: LLD (required in "passive initialization model",
|
||||
* should not be defined in hotplug model)
|
||||
**/
|
||||
int release(struct Scsi_Host * shp)
|
||||
|
||||
|
||||
/**
|
||||
* slave_alloc - prior to any commands being sent to a new device
|
||||
* (i.e. just prior to scan) this call is made
|
||||
|
|
|
@ -518,29 +518,6 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
|
|||
}
|
||||
EXPORT_SYMBOL(scsi_host_alloc);
|
||||
|
||||
struct Scsi_Host *scsi_register(struct scsi_host_template *sht, int privsize)
|
||||
{
|
||||
struct Scsi_Host *shost = scsi_host_alloc(sht, privsize);
|
||||
|
||||
if (!sht->detect) {
|
||||
printk(KERN_WARNING "scsi_register() called on new-style "
|
||||
"template for driver %s\n", sht->name);
|
||||
dump_stack();
|
||||
}
|
||||
|
||||
if (shost)
|
||||
list_add_tail(&shost->sht_legacy_list, &sht->legacy_hosts);
|
||||
return shost;
|
||||
}
|
||||
EXPORT_SYMBOL(scsi_register);
|
||||
|
||||
void scsi_unregister(struct Scsi_Host *shost)
|
||||
{
|
||||
list_del(&shost->sht_legacy_list);
|
||||
scsi_host_put(shost);
|
||||
}
|
||||
EXPORT_SYMBOL(scsi_unregister);
|
||||
|
||||
static int __scsi_host_match(struct device *dev, const void *data)
|
||||
{
|
||||
struct Scsi_Host *p;
|
||||
|
|
|
@ -1,73 +0,0 @@
|
|||
/*
|
||||
* Copyright (C) 2003 Christoph Hellwig.
|
||||
* Released under GPL v2.
|
||||
*
|
||||
* Support for old-style host templates.
|
||||
*
|
||||
* NOTE: Do not use this for new drivers ever.
|
||||
*/
|
||||
|
||||
#include <linux/init.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/module.h>
|
||||
|
||||
#include <scsi/scsi_host.h>
|
||||
|
||||
|
||||
static int __init init_this_scsi_driver(void)
|
||||
{
|
||||
struct scsi_host_template *sht = &driver_template;
|
||||
struct Scsi_Host *shost;
|
||||
struct list_head *l;
|
||||
int error;
|
||||
|
||||
if (!sht->release) {
|
||||
printk(KERN_ERR
|
||||
"scsi HBA driver %s didn't set a release method.\n",
|
||||
sht->name);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
sht->module = THIS_MODULE;
|
||||
INIT_LIST_HEAD(&sht->legacy_hosts);
|
||||
|
||||
sht->detect(sht);
|
||||
if (list_empty(&sht->legacy_hosts))
|
||||
return -ENODEV;
|
||||
|
||||
list_for_each_entry(shost, &sht->legacy_hosts, sht_legacy_list) {
|
||||
error = scsi_add_host(shost, NULL);
|
||||
if (error)
|
||||
goto fail;
|
||||
scsi_scan_host(shost);
|
||||
}
|
||||
return 0;
|
||||
fail:
|
||||
l = &shost->sht_legacy_list;
|
||||
while ((l = l->prev) != &sht->legacy_hosts)
|
||||
scsi_remove_host(list_entry(l, struct Scsi_Host, sht_legacy_list));
|
||||
return error;
|
||||
}
|
||||
|
||||
static void __exit exit_this_scsi_driver(void)
|
||||
{
|
||||
struct scsi_host_template *sht = &driver_template;
|
||||
struct Scsi_Host *shost, *s;
|
||||
|
||||
list_for_each_entry(shost, &sht->legacy_hosts, sht_legacy_list)
|
||||
scsi_remove_host(shost);
|
||||
list_for_each_entry_safe(shost, s, &sht->legacy_hosts, sht_legacy_list)
|
||||
sht->release(shost);
|
||||
|
||||
if (list_empty(&sht->legacy_hosts))
|
||||
return;
|
||||
|
||||
printk(KERN_WARNING "%s did not call scsi_unregister\n", sht->name);
|
||||
dump_stack();
|
||||
|
||||
list_for_each_entry_safe(shost, s, &sht->legacy_hosts, sht_legacy_list)
|
||||
scsi_unregister(shost);
|
||||
}
|
||||
|
||||
module_init(init_this_scsi_driver);
|
||||
module_exit(exit_this_scsi_driver);
|
|
@ -51,21 +51,6 @@ struct scsi_host_template {
|
|||
struct module *module;
|
||||
const char *name;
|
||||
|
||||
/*
|
||||
* Used to initialize old-style drivers. For new-style drivers
|
||||
* just perform all work in your module initialization function.
|
||||
*
|
||||
* Status: OBSOLETE
|
||||
*/
|
||||
int (* detect)(struct scsi_host_template *);
|
||||
|
||||
/*
|
||||
* Used as unload callback for hosts with old-style drivers.
|
||||
*
|
||||
* Status: OBSOLETE
|
||||
*/
|
||||
int (* release)(struct Scsi_Host *);
|
||||
|
||||
/*
|
||||
* The info function will return whatever useful information the
|
||||
* developer sees fit. If not provided, then the name field will
|
||||
|
@ -482,15 +467,6 @@ struct scsi_host_template {
|
|||
*/
|
||||
const struct attribute_group **sdev_groups;
|
||||
|
||||
/*
|
||||
* List of hosts per template.
|
||||
*
|
||||
* This is only for use by scsi_module.c for legacy templates.
|
||||
* For these access to it is synchronized implicitly by
|
||||
* module_init/module_exit.
|
||||
*/
|
||||
struct list_head legacy_hosts;
|
||||
|
||||
/*
|
||||
* Vendor Identifier associated with the host
|
||||
*
|
||||
|
@ -713,15 +689,6 @@ struct Scsi_Host {
|
|||
/* ldm bits */
|
||||
struct device shost_gendev, shost_dev;
|
||||
|
||||
/*
|
||||
* List of hosts per template.
|
||||
*
|
||||
* This is only for use by scsi_module.c for legacy templates.
|
||||
* For these access to it is synchronized implicitly by
|
||||
* module_init/module_exit.
|
||||
*/
|
||||
struct list_head sht_legacy_list;
|
||||
|
||||
/*
|
||||
* Points to the transport data (if any) which is allocated
|
||||
* separately
|
||||
|
@ -922,9 +889,6 @@ static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
|
|||
return shost->prot_guard_type;
|
||||
}
|
||||
|
||||
/* legacy interfaces */
|
||||
extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
|
||||
extern void scsi_unregister(struct Scsi_Host *);
|
||||
extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
|
||||
|
||||
#endif /* _SCSI_SCSI_HOST_H */
|
||||
|
|
Loading…
Reference in a new issue