linux/drivers/s390/char/sclp.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
// SPDX-License-Identifier: GPL-2.0
/*
* core function to access sclp interface
*
* Copyright IBM Corp. 1999, 2009
*
* Author(s): Martin Peschke <mpeschke@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/reboot.h>
#include <linux/jiffies.h>
#include <linux/init.h>
#include <linux/suspend.h>
#include <linux/completion.h>
#include <linux/platform_device.h>
#include <asm/types.h>
#include <asm/irq.h>
#include "sclp.h"
#define SCLP_HEADER "sclp: "
/* Lock to protect internal data consistency. */
static DEFINE_SPINLOCK(sclp_lock);
/* Mask of events that we can send to the sclp interface. */
static sccb_mask_t sclp_receive_mask;
/* Mask of events that we can receive from the sclp interface. */
static sccb_mask_t sclp_send_mask;
/* List of registered event listeners and senders. */
static struct list_head sclp_reg_list;
/* List of queued requests. */
static struct list_head sclp_req_queue;
/* Data for read and and init requests. */
static struct sclp_req sclp_read_req;
static struct sclp_req sclp_init_req;
static char sclp_read_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
static char sclp_init_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
/* Suspend request */
static DECLARE_COMPLETION(sclp_request_queue_flushed);
/* Number of console pages to allocate, used by sclp_con.c and sclp_vt220.c */
int sclp_console_pages = SCLP_CONSOLE_PAGES;
/* Flag to indicate if buffer pages are dropped on buffer full condition */
int sclp_console_drop = 1;
/* Number of times the console dropped buffer pages */
unsigned long sclp_console_full;
static void sclp_suspend_req_cb(struct sclp_req *req, void *data)
{
complete(&sclp_request_queue_flushed);
}
static int __init sclp_setup_console_pages(char *str)
{
int pages, rc;
rc = kstrtoint(str, 0, &pages);
if (!rc && pages >= SCLP_CONSOLE_PAGES)
sclp_console_pages = pages;
return 1;
}
__setup("sclp_con_pages=", sclp_setup_console_pages);
static int __init sclp_setup_console_drop(char *str)
{
int drop, rc;
rc = kstrtoint(str, 0, &drop);
if (!rc)
sclp_console_drop = drop;
return 1;
}
__setup("sclp_con_drop=", sclp_setup_console_drop);
static struct sclp_req sclp_suspend_req;
/* Timer for request retries. */
static struct timer_list sclp_request_timer;
/* Timer for queued requests. */
static struct timer_list sclp_queue_timer;
/* Internal state: is a request active at the sclp? */
static volatile enum sclp_running_state_t {
sclp_running_state_idle,
sclp_running_state_running,
sclp_running_state_reset_pending
} sclp_running_state = sclp_running_state_idle;
/* Internal state: is a read request pending? */
static volatile enum sclp_reading_state_t {
sclp_reading_state_idle,
sclp_reading_state_reading
} sclp_reading_state = sclp_reading_state_idle;
/* Internal state: is the driver currently serving requests? */
static volatile enum sclp_activation_state_t {
sclp_activation_state_active,
sclp_activation_state_deactivating,
sclp_activation_state_inactive,
sclp_activation_state_activating
} sclp_activation_state = sclp_activation_state_active;
/* Internal state: is an init mask request pending? */
static volatile enum sclp_mask_state_t {
sclp_mask_state_idle,
sclp_mask_state_initializing
} sclp_mask_state = sclp_mask_state_idle;
/* Internal state: is the driver suspended? */
static enum sclp_suspend_state_t {
sclp_suspend_state_running,
sclp_suspend_state_suspended,
} sclp_suspend_state = sclp_suspend_state_running;
/* Maximum retry counts */
#define SCLP_INIT_RETRY 3
#define SCLP_MASK_RETRY 3
/* Timeout intervals in seconds.*/
#define SCLP_BUSY_INTERVAL 10
#define SCLP_RETRY_INTERVAL 30
static void sclp_request_timeout(bool force_restart);
static void sclp_process_queue(void);
static void __sclp_make_read_req(void);
static int sclp_init_mask(int calculate);
static int sclp_init(void);
static void
__sclp_queue_read_req(void)
{
if (sclp_reading_state == sclp_reading_state_idle) {
sclp_reading_state = sclp_reading_state_reading;
__sclp_make_read_req();
/* Add request to head of queue */
list_add(&sclp_read_req.list, &sclp_req_queue);
}
}
/* Set up request retry timer. Called while sclp_lock is locked. */
static inline void
__sclp_set_request_timer(unsigned long time, void (*cb)(struct timer_list *))
{
del_timer(&sclp_request_timer);
sclp_request_timer.function = cb;
sclp_request_timer.expires = jiffies + time;
add_timer(&sclp_request_timer);
}
static void sclp_request_timeout_restart(struct timer_list *unused)
{
sclp_request_timeout(true);
}
static void sclp_request_timeout_normal(struct timer_list *unused)
{
sclp_request_timeout(false);
}
/* Request timeout handler. Restart the request queue. If force_restart,
* force restart of running request. */
static void sclp_request_timeout(bool force_restart)
{
unsigned long flags;
spin_lock_irqsave(&sclp_lock, flags);
if (force_restart) {
if (sclp_running_state == sclp_running_state_running) {
/* Break running state and queue NOP read event request
* to get a defined interface state. */
__sclp_queue_read_req();
sclp_running_state = sclp_running_state_idle;
}
} else {
__sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ,
sclp_request_timeout_normal);
}
spin_unlock_irqrestore(&sclp_lock, flags);
sclp_process_queue();
}
/*
* Returns the expire value in jiffies of the next pending request timeout,
* if any. Needs to be called with sclp_lock.
*/
static unsigned long __sclp_req_queue_find_next_timeout(void)
{
unsigned long expires_next = 0;
struct sclp_req *req;
list_for_each_entry(req, &sclp_req_queue, list) {
if (!req->queue_expires)
continue;
if (!expires_next ||
(time_before(req->queue_expires, expires_next)))
expires_next = req->queue_expires;
}
return expires_next;
}
/*
* Returns expired request, if any, and removes it from the list.
*/
static struct sclp_req *__sclp_req_queue_remove_expired_req(void)
{
unsigned long flags, now;
struct sclp_req *req;
spin_lock_irqsave(&sclp_lock, flags);
now = jiffies;
/* Don't need list_for_each_safe because we break out after list_del */
list_for_each_entry(req, &sclp_req_queue, list) {
if (!req->queue_expires)
continue;
if (time_before_eq(req->queue_expires, now)) {
if (req->status == SCLP_REQ_QUEUED) {
req->status = SCLP_REQ_QUEUED_TIMEOUT;
list_del(&req->list);
goto out;
}
}
}
req = NULL;
out:
spin_unlock_irqrestore(&sclp_lock, flags);
return req;
}
/*
* Timeout handler for queued requests. Removes request from list and
* invokes callback. This timer can be set per request in situations where
* waiting too long would be harmful to the system, e.g. during SE reboot.
*/
static void sclp_req_queue_timeout(struct timer_list *unused)
{
unsigned long flags, expires_next;
struct sclp_req *req;
do {
req = __sclp_req_queue_remove_expired_req();
if (req && req->callback)
req->callback(req, req->callback_data);
} while (req);
spin_lock_irqsave(&sclp_lock, flags);
expires_next = __sclp_req_queue_find_next_timeout();
if (expires_next)
mod_timer(&sclp_queue_timer, expires_next);
spin_unlock_irqrestore(&sclp_lock, flags);
}
/* Try to start a request. Return zero if the request was successfully
* started or if it will be started at a later time. Return non-zero otherwise.
* Called while sclp_lock is locked. */
static int
__sclp_start_request(struct sclp_req *req)
{
int rc;
if (sclp_running_state != sclp_running_state_idle)
return 0;
del_timer(&sclp_request_timer);
rc = sclp_service_call(req->command, req->sccb);
req->start_count++;
if (rc == 0) {
/* Successfully started request */
req->status = SCLP_REQ_RUNNING;
sclp_running_state = sclp_running_state_running;
__sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ,
sclp_request_timeout_restart);
return 0;
} else if (rc == -EBUSY) {
/* Try again later */
__sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ,
sclp_request_timeout_normal);
return 0;
}
/* Request failed */
req->status = SCLP_REQ_FAILED;
return rc;
}
/* Try to start queued requests. */
static void
sclp_process_queue(void)
{
struct sclp_req *req;
int rc;
unsigned long flags;
spin_lock_irqsave(&sclp_lock, flags);
if (sclp_running_state != sclp_running_state_idle) {
spin_unlock_irqrestore(&sclp_lock, flags);
return;
}
del_timer(&sclp_request_timer);
while (!list_empty(&sclp_req_queue)) {
req = list_entry(sclp_req_queue.next, struct sclp_req, list);
if (!req->sccb)
goto do_post;
rc = __sclp_start_request(req);
if (rc == 0)
break;
/* Request failed */
if (req->start_count > 1) {
/* Cannot abort already submitted request - could still
* be active at the SCLP */
__sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ,
sclp_request_timeout_normal);
break;
}
do_post:
/* Post-processing for aborted request */
list_del(&req->list);
if (req->callback) {
spin_unlock_irqrestore(&sclp_lock, flags);
req->callback(req, req->callback_data);
spin_lock_irqsave(&sclp_lock, flags);
}
}
spin_unlock_irqrestore(&sclp_lock, flags);
}
static int __sclp_can_add_request(struct sclp_req *req)
{
if (req == &sclp_suspend_req || req == &sclp_init_req)
return 1;
if (sclp_suspend_state != sclp_suspend_state_running)
return 0;
if (sclp_init_state != sclp_init_state_initialized)
return 0;
if (sclp_activation_state != sclp_activation_state_active)
return 0;
return 1;
}
/* Queue a new request. Return zero on success, non-zero otherwise. */
int
sclp_add_request(struct sclp_req *req)
{
unsigned long flags;
int rc;
spin_lock_irqsave(&sclp_lock, flags);
if (!__sclp_can_add_request(req)) {
spin_unlock_irqrestore(&sclp_lock, flags);
return -EIO;
}
req->status = SCLP_REQ_QUEUED;
req->start_count = 0;
list_add_tail(&req->list, &sclp_req_queue);
rc = 0;
if (req->queue_timeout) {
req->queue_expires = jiffies + req->queue_timeout * HZ;
if (!timer_pending(&sclp_queue_timer) ||
time_after(sclp_queue_timer.expires, req->queue_expires))
mod_timer(&sclp_queue_timer, req->queue_expires);
} else
req->queue_expires = 0;
/* Start if request is first in list */
if (sclp_running_state == sclp_running_state_idle &&
req->list.prev == &sclp_req_queue) {
if (!req->sccb) {
list_del(&req->list);
rc = -ENODATA;
goto out;
}
rc = __sclp_start_request(req);
if (rc)
list_del(&req->list);
}
out:
spin_unlock_irqrestore(&sclp_lock, flags);
return rc;
}
EXPORT_SYMBOL(sclp_add_request);
/* Dispatch events found in request buffer to registered listeners. Return 0
* if all events were dispatched, non-zero otherwise. */
static int
sclp_dispatch_evbufs(struct sccb_header *sccb)
{
unsigned long flags;
struct evbuf_header *evbuf;
struct list_head *l;
struct sclp_register *reg;
int offset;
int rc;
spin_lock_irqsave(&sclp_lock, flags);
rc = 0;
for (offset = sizeof(struct sccb_header); offset < sccb->length;
offset += evbuf->length) {
evbuf = (struct evbuf_header *) ((addr_t) sccb + offset);
/* Check for malformed hardware response */
if (evbuf->length == 0)
break;
/* Search for event handler */
reg = NULL;
list_for_each(l, &sclp_reg_list) {
reg = list_entry(l, struct sclp_register, list);
if (reg->receive_mask & SCLP_EVTYP_MASK(evbuf->type))
break;
else
reg = NULL;
}
if (reg && reg->receiver_fn) {
spin_unlock_irqrestore(&sclp_lock, flags);
reg->receiver_fn(evbuf);
spin_lock_irqsave(&sclp_lock, flags);
} else if (reg == NULL)
rc = -EOPNOTSUPP;
}
spin_unlock_irqrestore(&sclp_lock, flags);
return rc;
}
/* Read event data request callback. */
static void
sclp_read_cb(struct sclp_req *req, void *data)
{
unsigned long flags;
struct sccb_header *sccb;
sccb = (struct sccb_header *) req->sccb;
if (req->status == SCLP_REQ_DONE && (sccb->response_code == 0x20 ||
sccb->response_code == 0x220))
sclp_dispatch_evbufs(sccb);
spin_lock_irqsave(&sclp_lock, flags);
sclp_reading_state = sclp_reading_state_idle;
spin_unlock_irqrestore(&sclp_lock, flags);
}
/* Prepare read event data request. Called while sclp_lock is locked. */
static void __sclp_make_read_req(void)
{
struct sccb_header *sccb;
sccb = (struct sccb_header *) sclp_read_sccb;
clear_page(sccb);
memset(&sclp_read_req, 0, sizeof(struct sclp_req));
sclp_read_req.command = SCLP_CMDW_READ_EVENT_DATA;
sclp_read_req.status = SCLP_REQ_QUEUED;
sclp_read_req.start_count = 0;
sclp_read_req.callback = sclp_read_cb;
sclp_read_req.sccb = sccb;
sccb->length = PAGE_SIZE;
sccb->function_code = 0;
sccb->control_mask[2] = 0x80;
}
/* Search request list for request with matching sccb. Return request if found,
* NULL otherwise. Called while sclp_lock is locked. */
static inline struct sclp_req *
__sclp_find_req(u32 sccb)
{
struct list_head *l;
struct sclp_req *req;
list_for_each(l, &sclp_req_queue) {
req = list_entry(l, struct sclp_req, list);
if (sccb == (u32) (addr_t) req->sccb)
return req;
}
return NULL;
}
/* Handler for external interruption. Perform request post-processing.
* Prepare read event data request if necessary. Start processing of next
* request on queue. */
static void sclp_interrupt_handler(struct ext_code ext_code,
unsigned int param32, unsigned long param64)
{
struct sclp_req *req;
u32 finished_sccb;
u32 evbuf_pending;
inc_irq_stat(IRQEXT_SCP);
spin_lock(&sclp_lock);
finished_sccb = param32 & 0xfffffff8;
evbuf_pending = param32 & 0x3;
if (finished_sccb) {
del_timer(&sclp_request_timer);
sclp_running_state = sclp_running_state_reset_pending;
req = __sclp_find_req(finished_sccb);
if (req) {
/* Request post-processing */
list_del(&req->list);
req->status = SCLP_REQ_DONE;
if (req->callback) {
spin_unlock(&sclp_lock);
req->callback(req, req->callback_data);
spin_lock(&sclp_lock);
}
}
sclp_running_state = sclp_running_state_idle;
}
if (evbuf_pending &&
sclp_activation_state == sclp_activation_state_active)
__sclp_queue_read_req();
spin_unlock(&sclp_lock);
sclp_process_queue();
}
/* Convert interval in jiffies to TOD ticks. */
static inline u64
sclp_tod_from_jiffies(unsigned long jiffies)
{
return (u64) (jiffies / HZ) << 32;
}
/* Wait until a currently running request finished. Note: while this function
* is running, no timers are served on the calling CPU. */
void
sclp_sync_wait(void)
{
unsigned long long old_tick;
unsigned long flags;
unsigned long cr0, cr0_sync;
u64 timeout;
int irq_context;
/* We'll be disabling timer interrupts, so we need a custom timeout
* mechanism */
timeout = 0;
if (timer_pending(&sclp_request_timer)) {
/* Get timeout TOD value */
timeout = get_tod_clock_fast() +
sclp_tod_from_jiffies(sclp_request_timer.expires -
jiffies);
}
local_irq_save(flags);
/* Prevent bottom half from executing once we force interrupts open */
irq_context = in_interrupt();
if (!irq_context)
local_bh_disable();
/* Enable service-signal interruption, disable timer interrupts */
old_tick = local_tick_disable();
trace_hardirqs_on();
__ctl_store(cr0, 0, 0);
cr0_sync = cr0 & ~CR0_IRQ_SUBCLASS_MASK;
cr0_sync |= 1UL << (63 - 54);
__ctl_load(cr0_sync, 0, 0);
Fix IRQ flag handling naming Fix the IRQ flag handling naming. In linux/irqflags.h under one configuration, it maps: local_irq_enable() -> raw_local_irq_enable() local_irq_disable() -> raw_local_irq_disable() local_irq_save() -> raw_local_irq_save() ... and under the other configuration, it maps: raw_local_irq_enable() -> local_irq_enable() raw_local_irq_disable() -> local_irq_disable() raw_local_irq_save() -> local_irq_save() ... This is quite confusing. There should be one set of names expected of the arch, and this should be wrapped to give another set of names that are expected by users of this facility. Change this to have the arch provide: flags = arch_local_save_flags() flags = arch_local_irq_save() arch_local_irq_restore(flags) arch_local_irq_disable() arch_local_irq_enable() arch_irqs_disabled_flags(flags) arch_irqs_disabled() arch_safe_halt() Then linux/irqflags.h wraps these to provide: raw_local_save_flags(flags) raw_local_irq_save(flags) raw_local_irq_restore(flags) raw_local_irq_disable() raw_local_irq_enable() raw_irqs_disabled_flags(flags) raw_irqs_disabled() raw_safe_halt() with type checking on the flags 'arguments', and then wraps those to provide: local_save_flags(flags) local_irq_save(flags) local_irq_restore(flags) local_irq_disable() local_irq_enable() irqs_disabled_flags(flags) irqs_disabled() safe_halt() with tracing included if enabled. The arch functions can now all be inline functions rather than some of them having to be macros. Signed-off-by: David Howells <dhowells@redhat.com> [X86, FRV, MN10300] Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [Tile] Signed-off-by: Michal Simek <monstr@monstr.eu> [Microblaze] Tested-by: Catalin Marinas <catalin.marinas@arm.com> [ARM] Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [AVR] Acked-by: Tony Luck <tony.luck@intel.com> [IA-64] Acked-by: Hirokazu Takata <takata@linux-m32r.org> [M32R] Acked-by: Greg Ungerer <gerg@uclinux.org> [M68K/M68KNOMMU] Acked-by: Ralf Baechle <ralf@linux-mips.org> [MIPS] Acked-by: Kyle McMartin <kyle@mcmartin.ca> [PA-RISC] Acked-by: Paul Mackerras <paulus@samba.org> [PowerPC] Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [S390] Acked-by: Chen Liqin <liqin.chen@sunplusct.com> [Score] Acked-by: Matt Fleming <matt@console-pimps.org> [SH] Acked-by: David S. Miller <davem@davemloft.net> [Sparc] Acked-by: Chris Zankel <chris@zankel.net> [Xtensa] Reviewed-by: Richard Henderson <rth@twiddle.net> [Alpha] Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp> [H8300] Cc: starvik@axis.com [CRIS] Cc: jesper.nilsson@axis.com [CRIS] Cc: linux-cris-kernel@axis.com
2010-10-07 21:08:55 +08:00
__arch_local_irq_stosm(0x01);
/* Loop until driver state indicates finished request */
while (sclp_running_state != sclp_running_state_idle) {
/* Check for expired request timer */
if (timer_pending(&sclp_request_timer) &&
get_tod_clock_fast() > timeout &&
del_timer(&sclp_request_timer))
sclp_request_timer.function(&sclp_request_timer);
cpu_relax();
}
local_irq_disable();
__ctl_load(cr0, 0, 0);
if (!irq_context)
_local_bh_enable();
local_tick_enable(old_tick);
local_irq_restore(flags);
}
EXPORT_SYMBOL(sclp_sync_wait);
/* Dispatch changes in send and receive mask to registered listeners. */
static void
sclp_dispatch_state_change(void)
{
struct list_head *l;
struct sclp_register *reg;
unsigned long flags;
sccb_mask_t receive_mask;
sccb_mask_t send_mask;
do {
spin_lock_irqsave(&sclp_lock, flags);
reg = NULL;
list_for_each(l, &sclp_reg_list) {
reg = list_entry(l, struct sclp_register, list);
receive_mask = reg->send_mask & sclp_receive_mask;
send_mask = reg->receive_mask & sclp_send_mask;
if (reg->sclp_receive_mask != receive_mask ||
reg->sclp_send_mask != send_mask) {
reg->sclp_receive_mask = receive_mask;
reg->sclp_send_mask = send_mask;
break;
} else
reg = NULL;
}
spin_unlock_irqrestore(&sclp_lock, flags);
if (reg && reg->state_change_fn)
reg->state_change_fn(reg);
} while (reg);
}
struct sclp_statechangebuf {
struct evbuf_header header;
u8 validity_sclp_active_facility_mask : 1;
u8 validity_sclp_receive_mask : 1;
u8 validity_sclp_send_mask : 1;
u8 validity_read_data_function_mask : 1;
u16 _zeros : 12;
u16 mask_length;
u64 sclp_active_facility_mask;
u8 masks[2 * 1021 + 4]; /* variable length */
/*
* u8 sclp_receive_mask[mask_length];
* u8 sclp_send_mask[mask_length];
* u32 read_data_function_mask;
*/
} __attribute__((packed));
/* State change event callback. Inform listeners of changes. */
static void
sclp_state_change_cb(struct evbuf_header *evbuf)
{
unsigned long flags;
struct sclp_statechangebuf *scbuf;
BUILD_BUG_ON(sizeof(struct sclp_statechangebuf) > PAGE_SIZE);
scbuf = (struct sclp_statechangebuf *) evbuf;
spin_lock_irqsave(&sclp_lock, flags);
if (scbuf->validity_sclp_receive_mask)
sclp_receive_mask = sccb_get_recv_mask(scbuf);
if (scbuf->validity_sclp_send_mask)
sclp_send_mask = sccb_get_send_mask(scbuf);
spin_unlock_irqrestore(&sclp_lock, flags);
if (scbuf->validity_sclp_active_facility_mask)
sclp.facilities = scbuf->sclp_active_facility_mask;
sclp_dispatch_state_change();
}
static struct sclp_register sclp_state_change_event = {
.receive_mask = EVTYP_STATECHANGE_MASK,
.receiver_fn = sclp_state_change_cb
};
/* Calculate receive and send mask of currently registered listeners.
* Called while sclp_lock is locked. */
static inline void
__sclp_get_mask(sccb_mask_t *receive_mask, sccb_mask_t *send_mask)
{
struct list_head *l;
struct sclp_register *t;
*receive_mask = 0;
*send_mask = 0;
list_for_each(l, &sclp_reg_list) {
t = list_entry(l, struct sclp_register, list);
*receive_mask |= t->receive_mask;
*send_mask |= t->send_mask;
}
}
/* Register event listener. Return 0 on success, non-zero otherwise. */
int
sclp_register(struct sclp_register *reg)
{
unsigned long flags;
sccb_mask_t receive_mask;
sccb_mask_t send_mask;
int rc;
rc = sclp_init();
if (rc)
return rc;
spin_lock_irqsave(&sclp_lock, flags);
/* Check event mask for collisions */
__sclp_get_mask(&receive_mask, &send_mask);
if (reg->receive_mask & receive_mask || reg->send_mask & send_mask) {
spin_unlock_irqrestore(&sclp_lock, flags);
return -EBUSY;
}
/* Trigger initial state change callback */
reg->sclp_receive_mask = 0;
reg->sclp_send_mask = 0;
reg->pm_event_posted = 0;
list_add(&reg->list, &sclp_reg_list);
spin_unlock_irqrestore(&sclp_lock, flags);
rc = sclp_init_mask(1);
if (rc) {
spin_lock_irqsave(&sclp_lock, flags);
list_del(&reg->list);
spin_unlock_irqrestore(&sclp_lock, flags);
}
return rc;
}
EXPORT_SYMBOL(sclp_register);
/* Unregister event listener. */
void
sclp_unregister(struct sclp_register *reg)
{
unsigned long flags;
spin_lock_irqsave(&sclp_lock, flags);
list_del(&reg->list);
spin_unlock_irqrestore(&sclp_lock, flags);
sclp_init_mask(1);
}
EXPORT_SYMBOL(sclp_unregister);
/* Remove event buffers which are marked processed. Return the number of
* remaining event buffers. */
int
sclp_remove_processed(struct sccb_header *sccb)
{
struct evbuf_header *evbuf;
int unprocessed;
u16 remaining;
evbuf = (struct evbuf_header *) (sccb + 1);
unprocessed = 0;
remaining = sccb->length - sizeof(struct sccb_header);
while (remaining > 0) {
remaining -= evbuf->length;
if (evbuf->flags & 0x80) {
sccb->length -= evbuf->length;
memcpy(evbuf, (void *) ((addr_t) evbuf + evbuf->length),
remaining);
} else {
unprocessed++;
evbuf = (struct evbuf_header *)
((addr_t) evbuf + evbuf->length);
}
}
return unprocessed;
}
EXPORT_SYMBOL(sclp_remove_processed);
/* Prepare init mask request. Called while sclp_lock is locked. */
static inline void
__sclp_make_init_req(sccb_mask_t receive_mask, sccb_mask_t send_mask)
{
struct init_sccb *sccb;
sccb = (struct init_sccb *) sclp_init_sccb;
clear_page(sccb);
memset(&sclp_init_req, 0, sizeof(struct sclp_req));
sclp_init_req.command = SCLP_CMDW_WRITE_EVENT_MASK;
sclp_init_req.status = SCLP_REQ_FILLED;
sclp_init_req.start_count = 0;
sclp_init_req.callback = NULL;
sclp_init_req.callback_data = NULL;
sclp_init_req.sccb = sccb;
sccb->header.length = sizeof(*sccb);
if (sclp_mask_compat_mode)
sccb->mask_length = SCLP_MASK_SIZE_COMPAT;
else
sccb->mask_length = sizeof(sccb_mask_t);
sccb_set_recv_mask(sccb, receive_mask);
sccb_set_send_mask(sccb, send_mask);
sccb_set_sclp_recv_mask(sccb, 0);
sccb_set_sclp_send_mask(sccb, 0);
}
/* Start init mask request. If calculate is non-zero, calculate the mask as
* requested by registered listeners. Use zero mask otherwise. Return 0 on
* success, non-zero otherwise. */
static int
sclp_init_mask(int calculate)
{
unsigned long flags;
struct init_sccb *sccb = (struct init_sccb *) sclp_init_sccb;
sccb_mask_t receive_mask;
sccb_mask_t send_mask;
int retry;
int rc;
unsigned long wait;
spin_lock_irqsave(&sclp_lock, flags);
/* Check if interface is in appropriate state */
if (sclp_mask_state != sclp_mask_state_idle) {
spin_unlock_irqrestore(&sclp_lock, flags);
return -EBUSY;
}
if (sclp_activation_state == sclp_activation_state_inactive) {
spin_unlock_irqrestore(&sclp_lock, flags);
return -EINVAL;
}
sclp_mask_state = sclp_mask_state_initializing;
/* Determine mask */
if (calculate)
__sclp_get_mask(&receive_mask, &send_mask);
else {
receive_mask = 0;
send_mask = 0;
}
rc = -EIO;
for (retry = 0; retry <= SCLP_MASK_RETRY; retry++) {
/* Prepare request */
__sclp_make_init_req(receive_mask, send_mask);
spin_unlock_irqrestore(&sclp_lock, flags);
if (sclp_add_request(&sclp_init_req)) {
/* Try again later */
wait = jiffies + SCLP_BUSY_INTERVAL * HZ;
while (time_before(jiffies, wait))
sclp_sync_wait();
spin_lock_irqsave(&sclp_lock, flags);
continue;
}
while (sclp_init_req.status != SCLP_REQ_DONE &&
sclp_init_req.status != SCLP_REQ_FAILED)
sclp_sync_wait();
spin_lock_irqsave(&sclp_lock, flags);
if (sclp_init_req.status == SCLP_REQ_DONE &&
sccb->header.response_code == 0x20) {
/* Successful request */
if (calculate) {
sclp_receive_mask = sccb_get_sclp_recv_mask(sccb);
sclp_send_mask = sccb_get_sclp_send_mask(sccb);
} else {
sclp_receive_mask = 0;
sclp_send_mask = 0;
}
spin_unlock_irqrestore(&sclp_lock, flags);
sclp_dispatch_state_change();
spin_lock_irqsave(&sclp_lock, flags);
rc = 0;
break;
}
}
sclp_mask_state = sclp_mask_state_idle;
spin_unlock_irqrestore(&sclp_lock, flags);
return rc;
}
/* Deactivate SCLP interface. On success, new requests will be rejected,
* events will no longer be dispatched. Return 0 on success, non-zero
* otherwise. */
int
sclp_deactivate(void)
{
unsigned long flags;
int rc;
spin_lock_irqsave(&sclp_lock, flags);
/* Deactivate can only be called when active */
if (sclp_activation_state != sclp_activation_state_active) {
spin_unlock_irqrestore(&sclp_lock, flags);
return -EINVAL;
}
sclp_activation_state = sclp_activation_state_deactivating;
spin_unlock_irqrestore(&sclp_lock, flags);
rc = sclp_init_mask(0);
spin_lock_irqsave(&sclp_lock, flags);
if (rc == 0)
sclp_activation_state = sclp_activation_state_inactive;
else
sclp_activation_state = sclp_activation_state_active;
spin_unlock_irqrestore(&sclp_lock, flags);
return rc;
}
EXPORT_SYMBOL(sclp_deactivate);
/* Reactivate SCLP interface after sclp_deactivate. On success, new
* requests will be accepted, events will be dispatched again. Return 0 on
* success, non-zero otherwise. */
int
sclp_reactivate(void)
{
unsigned long flags;
int rc;
spin_lock_irqsave(&sclp_lock, flags);
/* Reactivate can only be called when inactive */
if (sclp_activation_state != sclp_activation_state_inactive) {
spin_unlock_irqrestore(&sclp_lock, flags);
return -EINVAL;
}
sclp_activation_state = sclp_activation_state_activating;
spin_unlock_irqrestore(&sclp_lock, flags);
rc = sclp_init_mask(1);
spin_lock_irqsave(&sclp_lock, flags);
if (rc == 0)
sclp_activation_state = sclp_activation_state_active;
else
sclp_activation_state = sclp_activation_state_inactive;
spin_unlock_irqrestore(&sclp_lock, flags);
return rc;
}
EXPORT_SYMBOL(sclp_reactivate);
/* Handler for external interruption used during initialization. Modify
* request state to done. */
static void sclp_check_handler(struct ext_code ext_code,
unsigned int param32, unsigned long param64)
{
u32 finished_sccb;
inc_irq_stat(IRQEXT_SCP);
finished_sccb = param32 & 0xfffffff8;
/* Is this the interrupt we are waiting for? */
if (finished_sccb == 0)
return;
if (finished_sccb != (u32) (addr_t) sclp_init_sccb)
panic("sclp: unsolicited interrupt for buffer at 0x%x\n",
finished_sccb);
spin_lock(&sclp_lock);
if (sclp_running_state == sclp_running_state_running) {
sclp_init_req.status = SCLP_REQ_DONE;
sclp_running_state = sclp_running_state_idle;
}
spin_unlock(&sclp_lock);
}
/* Initial init mask request timed out. Modify request state to failed. */
static void
sclp_check_timeout(struct timer_list *unused)
{
unsigned long flags;
spin_lock_irqsave(&sclp_lock, flags);
if (sclp_running_state == sclp_running_state_running) {
sclp_init_req.status = SCLP_REQ_FAILED;
sclp_running_state = sclp_running_state_idle;
}
spin_unlock_irqrestore(&sclp_lock, flags);
}
/* Perform a check of the SCLP interface. Return zero if the interface is
* available and there are no pending requests from a previous instance.
* Return non-zero otherwise. */
static int
sclp_check_interface(void)
{
struct init_sccb *sccb;
unsigned long flags;
int retry;
int rc;
spin_lock_irqsave(&sclp_lock, flags);
/* Prepare init mask command */
rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler);
if (rc) {
spin_unlock_irqrestore(&sclp_lock, flags);
return rc;
}
for (retry = 0; retry <= SCLP_INIT_RETRY; retry++) {
__sclp_make_init_req(0, 0);
sccb = (struct init_sccb *) sclp_init_req.sccb;
rc = sclp_service_call(sclp_init_req.command, sccb);
if (rc == -EIO)
break;
sclp_init_req.status = SCLP_REQ_RUNNING;
sclp_running_state = sclp_running_state_running;
__sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ,
sclp_check_timeout);
spin_unlock_irqrestore(&sclp_lock, flags);
/* Enable service-signal interruption - needs to happen
* with IRQs enabled. */
irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
/* Wait for signal from interrupt or timeout */
sclp_sync_wait();
/* Disable service-signal interruption - needs to happen
* with IRQs enabled. */
irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL);
spin_lock_irqsave(&sclp_lock, flags);
del_timer(&sclp_request_timer);
rc = -EBUSY;
if (sclp_init_req.status == SCLP_REQ_DONE) {
if (sccb->header.response_code == 0x20) {
rc = 0;
break;
} else if (sccb->header.response_code == 0x74f0) {
if (!sclp_mask_compat_mode) {
sclp_mask_compat_mode = true;
retry = 0;
}
}
}
}
unregister_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler);
spin_unlock_irqrestore(&sclp_lock, flags);
return rc;
}
/* Reboot event handler. Reset send and receive mask to prevent pending SCLP
* events from interfering with rebooted system. */
static int
sclp_reboot_event(struct notifier_block *this, unsigned long event, void *ptr)
{
sclp_deactivate();
return NOTIFY_DONE;
}
static struct notifier_block sclp_reboot_notifier = {
.notifier_call = sclp_reboot_event
};
/*
* Suspend/resume SCLP notifier implementation
*/
static void sclp_pm_event(enum sclp_pm_event sclp_pm_event, int rollback)
{
struct sclp_register *reg;
unsigned long flags;
if (!rollback) {
spin_lock_irqsave(&sclp_lock, flags);
list_for_each_entry(reg, &sclp_reg_list, list)
reg->pm_event_posted = 0;
spin_unlock_irqrestore(&sclp_lock, flags);
}
do {
spin_lock_irqsave(&sclp_lock, flags);
list_for_each_entry(reg, &sclp_reg_list, list) {
if (rollback && reg->pm_event_posted)
goto found;
if (!rollback && !reg->pm_event_posted)
goto found;
}
spin_unlock_irqrestore(&sclp_lock, flags);
return;
found:
spin_unlock_irqrestore(&sclp_lock, flags);
if (reg->pm_event_fn)
reg->pm_event_fn(reg, sclp_pm_event);
reg->pm_event_posted = rollback ? 0 : 1;
} while (1);
}
/*
* Susend/resume callbacks for platform device
*/
static int sclp_freeze(struct device *dev)
{
unsigned long flags;
int rc;
sclp_pm_event(SCLP_PM_EVENT_FREEZE, 0);
spin_lock_irqsave(&sclp_lock, flags);
sclp_suspend_state = sclp_suspend_state_suspended;
spin_unlock_irqrestore(&sclp_lock, flags);
/* Init supend data */
memset(&sclp_suspend_req, 0, sizeof(sclp_suspend_req));
sclp_suspend_req.callback = sclp_suspend_req_cb;
sclp_suspend_req.status = SCLP_REQ_FILLED;
init_completion(&sclp_request_queue_flushed);
rc = sclp_add_request(&sclp_suspend_req);
if (rc == 0)
wait_for_completion(&sclp_request_queue_flushed);
else if (rc != -ENODATA)
goto fail_thaw;
rc = sclp_deactivate();
if (rc)
goto fail_thaw;
return 0;
fail_thaw:
spin_lock_irqsave(&sclp_lock, flags);
sclp_suspend_state = sclp_suspend_state_running;
spin_unlock_irqrestore(&sclp_lock, flags);
sclp_pm_event(SCLP_PM_EVENT_THAW, 1);
return rc;
}
static int sclp_undo_suspend(enum sclp_pm_event event)
{
unsigned long flags;
int rc;
rc = sclp_reactivate();
if (rc)
return rc;
spin_lock_irqsave(&sclp_lock, flags);
sclp_suspend_state = sclp_suspend_state_running;
spin_unlock_irqrestore(&sclp_lock, flags);
sclp_pm_event(event, 0);
return 0;
}
static int sclp_thaw(struct device *dev)
{
return sclp_undo_suspend(SCLP_PM_EVENT_THAW);
}
static int sclp_restore(struct device *dev)
{
return sclp_undo_suspend(SCLP_PM_EVENT_RESTORE);
}
static const struct dev_pm_ops sclp_pm_ops = {
.freeze = sclp_freeze,
.thaw = sclp_thaw,
.restore = sclp_restore,
};
static ssize_t con_pages_show(struct device_driver *dev, char *buf)
{
return sprintf(buf, "%i\n", sclp_console_pages);
}
static DRIVER_ATTR_RO(con_pages);
static ssize_t con_drop_show(struct device_driver *dev, char *buf)
{
return sprintf(buf, "%i\n", sclp_console_drop);
}
static DRIVER_ATTR_RO(con_drop);
static ssize_t con_full_show(struct device_driver *dev, char *buf)
{
return sprintf(buf, "%lu\n", sclp_console_full);
}
static DRIVER_ATTR_RO(con_full);
static struct attribute *sclp_drv_attrs[] = {
&driver_attr_con_pages.attr,
&driver_attr_con_drop.attr,
&driver_attr_con_full.attr,
NULL,
};
static struct attribute_group sclp_drv_attr_group = {
.attrs = sclp_drv_attrs,
};
static const struct attribute_group *sclp_drv_attr_groups[] = {
&sclp_drv_attr_group,
NULL,
};
static struct platform_driver sclp_pdrv = {
.driver = {
.name = "sclp",
.pm = &sclp_pm_ops,
.groups = sclp_drv_attr_groups,
},
};
static struct platform_device *sclp_pdev;
/* Initialize SCLP driver. Return zero if driver is operational, non-zero
* otherwise. */
static int
sclp_init(void)
{
unsigned long flags;
int rc = 0;
spin_lock_irqsave(&sclp_lock, flags);
/* Check for previous or running initialization */
if (sclp_init_state != sclp_init_state_uninitialized)
goto fail_unlock;
sclp_init_state = sclp_init_state_initializing;
/* Set up variables */
INIT_LIST_HEAD(&sclp_req_queue);
INIT_LIST_HEAD(&sclp_reg_list);
list_add(&sclp_state_change_event.list, &sclp_reg_list);
timer_setup(&sclp_request_timer, NULL, 0);
timer_setup(&sclp_queue_timer, sclp_req_queue_timeout, 0);
/* Check interface */
spin_unlock_irqrestore(&sclp_lock, flags);
rc = sclp_check_interface();
spin_lock_irqsave(&sclp_lock, flags);
if (rc)
goto fail_init_state_uninitialized;
/* Register reboot handler */
rc = register_reboot_notifier(&sclp_reboot_notifier);
if (rc)
goto fail_init_state_uninitialized;
/* Register interrupt handler */
rc = register_external_irq(EXT_IRQ_SERVICE_SIG, sclp_interrupt_handler);
if (rc)
goto fail_unregister_reboot_notifier;
sclp_init_state = sclp_init_state_initialized;
spin_unlock_irqrestore(&sclp_lock, flags);
/* Enable service-signal external interruption - needs to happen with
* IRQs enabled. */
irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
sclp_init_mask(1);
return 0;
fail_unregister_reboot_notifier:
unregister_reboot_notifier(&sclp_reboot_notifier);
fail_init_state_uninitialized:
sclp_init_state = sclp_init_state_uninitialized;
fail_unlock:
spin_unlock_irqrestore(&sclp_lock, flags);
return rc;
}
/*
* SCLP panic notifier: If we are suspended, we thaw SCLP in order to be able
* to print the panic message.
*/
static int sclp_panic_notify(struct notifier_block *self,
unsigned long event, void *data)
{
if (sclp_suspend_state == sclp_suspend_state_suspended)
sclp_undo_suspend(SCLP_PM_EVENT_THAW);
return NOTIFY_OK;
}
static struct notifier_block sclp_on_panic_nb = {
.notifier_call = sclp_panic_notify,
.priority = SCLP_PANIC_PRIO,
};
static __init int sclp_initcall(void)
{
int rc;
rc = platform_driver_register(&sclp_pdrv);
if (rc)
return rc;
sclp_pdev = platform_device_register_simple("sclp", -1, NULL, 0);
rc = PTR_ERR_OR_ZERO(sclp_pdev);
if (rc)
goto fail_platform_driver_unregister;
rc = atomic_notifier_chain_register(&panic_notifier_list,
&sclp_on_panic_nb);
if (rc)
goto fail_platform_device_unregister;
return sclp_init();
fail_platform_device_unregister:
platform_device_unregister(sclp_pdev);
fail_platform_driver_unregister:
platform_driver_unregister(&sclp_pdrv);
return rc;
}
arch_initcall(sclp_initcall);