linux/drivers/misc/ibmasm/command.c
Thomas Gleixner 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00

174 lines
4.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* IBM ASM Service Processor Device Driver
*
* Copyright (C) IBM Corporation, 2004
*
* Author: Max Asböck <amax@us.ibm.com>
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include "ibmasm.h"
#include "lowlevel.h"
static void exec_next_command(struct service_processor *sp);
static atomic_t command_count = ATOMIC_INIT(0);
struct command *ibmasm_new_command(struct service_processor *sp, size_t buffer_size)
{
struct command *cmd;
if (buffer_size > IBMASM_CMD_MAX_BUFFER_SIZE)
return NULL;
cmd = kzalloc(sizeof(struct command), GFP_KERNEL);
if (cmd == NULL)
return NULL;
cmd->buffer = kzalloc(buffer_size, GFP_KERNEL);
if (cmd->buffer == NULL) {
kfree(cmd);
return NULL;
}
cmd->buffer_size = buffer_size;
kref_init(&cmd->kref);
cmd->lock = &sp->lock;
cmd->status = IBMASM_CMD_PENDING;
init_waitqueue_head(&cmd->wait);
INIT_LIST_HEAD(&cmd->queue_node);
atomic_inc(&command_count);
dbg("command count: %d\n", atomic_read(&command_count));
return cmd;
}
void ibmasm_free_command(struct kref *kref)
{
struct command *cmd = to_command(kref);
list_del(&cmd->queue_node);
atomic_dec(&command_count);
dbg("command count: %d\n", atomic_read(&command_count));
kfree(cmd->buffer);
kfree(cmd);
}
static void enqueue_command(struct service_processor *sp, struct command *cmd)
{
list_add_tail(&cmd->queue_node, &sp->command_queue);
}
static struct command *dequeue_command(struct service_processor *sp)
{
struct command *cmd;
struct list_head *next;
if (list_empty(&sp->command_queue))
return NULL;
next = sp->command_queue.next;
list_del_init(next);
cmd = list_entry(next, struct command, queue_node);
return cmd;
}
static inline void do_exec_command(struct service_processor *sp)
{
char tsbuf[32];
dbg("%s:%d at %s\n", __func__, __LINE__, get_timestamp(tsbuf));
if (ibmasm_send_i2o_message(sp)) {
sp->current_command->status = IBMASM_CMD_FAILED;
wake_up(&sp->current_command->wait);
command_put(sp->current_command);
exec_next_command(sp);
}
}
/**
* exec_command
* send a command to a service processor
* Commands are executed sequentially. One command (sp->current_command)
* is sent to the service processor. Once the interrupt handler gets a
* message of type command_response, the message is copied into
* the current commands buffer,
*/
void ibmasm_exec_command(struct service_processor *sp, struct command *cmd)
{
unsigned long flags;
char tsbuf[32];
dbg("%s:%d at %s\n", __func__, __LINE__, get_timestamp(tsbuf));
spin_lock_irqsave(&sp->lock, flags);
if (!sp->current_command) {
sp->current_command = cmd;
command_get(sp->current_command);
spin_unlock_irqrestore(&sp->lock, flags);
do_exec_command(sp);
} else {
enqueue_command(sp, cmd);
spin_unlock_irqrestore(&sp->lock, flags);
}
}
static void exec_next_command(struct service_processor *sp)
{
unsigned long flags;
char tsbuf[32];
dbg("%s:%d at %s\n", __func__, __LINE__, get_timestamp(tsbuf));
spin_lock_irqsave(&sp->lock, flags);
sp->current_command = dequeue_command(sp);
if (sp->current_command) {
command_get(sp->current_command);
spin_unlock_irqrestore(&sp->lock, flags);
do_exec_command(sp);
} else {
spin_unlock_irqrestore(&sp->lock, flags);
}
}
/**
* Sleep until a command has failed or a response has been received
* and the command status been updated by the interrupt handler.
* (see receive_response).
*/
void ibmasm_wait_for_response(struct command *cmd, int timeout)
{
wait_event_interruptible_timeout(cmd->wait,
cmd->status == IBMASM_CMD_COMPLETE ||
cmd->status == IBMASM_CMD_FAILED,
timeout * HZ);
}
/**
* receive_command_response
* called by the interrupt handler when a dot command of type command_response
* was received.
*/
void ibmasm_receive_command_response(struct service_processor *sp, void *response, size_t size)
{
struct command *cmd = sp->current_command;
if (!sp->current_command)
return;
memcpy_fromio(cmd->buffer, response, min(size, cmd->buffer_size));
cmd->status = IBMASM_CMD_COMPLETE;
wake_up(&sp->current_command->wait);
command_put(sp->current_command);
exec_next_command(sp);
}