From 83c9f08e6c6a6dc668384882de4dcf5ef4ae0ba7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 19 Mar 2018 08:37:53 +0100 Subject: [PATCH] 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 Signed-off-by: Martin K. Petersen --- Documentation/driver-api/scsi.rst | 6 -- Documentation/scsi/scsi_mid_low_api.txt | 122 +----------------------- drivers/scsi/hosts.c | 23 ----- drivers/scsi/scsi_module.c | 73 -------------- include/scsi/scsi_host.h | 36 ------- 5 files changed, 1 insertion(+), 259 deletions(-) delete mode 100644 drivers/scsi/scsi_module.c diff --git a/Documentation/driver-api/scsi.rst b/Documentation/driver-api/scsi.rst index 3ae337929721..31ad0fed6763 100644 --- a/Documentation/driver-api/scsi.rst +++ b/Documentation/driver-api/scsi.rst @@ -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 ~~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt index 2c31d9ee6776..177c031763c0 100644 --- a/Documentation/scsi/scsi_mid_low_api.txt +++ b/Documentation/scsi/scsi_mid_low_api.txt @@ -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 diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 0a5362822ed6..ffd1030b6c91 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -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; diff --git a/drivers/scsi/scsi_module.c b/drivers/scsi/scsi_module.c deleted file mode 100644 index 489175833709..000000000000 --- a/drivers/scsi/scsi_module.c +++ /dev/null @@ -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 -#include -#include - -#include - - -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); diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 19317585ae48..4e418fb539f8 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -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 */