Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754835Ab0DWBLt (ORCPT ); Thu, 22 Apr 2010 21:11:49 -0400 Received: from mail-yw0-f194.google.com ([209.85.211.194]:50164 "EHLO mail-yw0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754668Ab0DWBKD (ORCPT ); Thu, 22 Apr 2010 21:10:03 -0400 From: =?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= To: linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= , Len Brown , Pavel Machek , "Rafael J. Wysocki" , Randy Dunlap , Jesse Barnes , Magnus Damm , Nigel Cunningham , Cornelia Huck , linux-doc@vger.kernel.org Subject: [PATCH 2/9] PM: suspend_block: Add driver to access suspend blockers from user-space Date: Thu, 22 Apr 2010 18:08:51 -0700 Message-Id: <1271984938-13920-3-git-send-email-arve@android.com> X-Mailer: git-send-email 1.6.5.1 In-Reply-To: <1271984938-13920-2-git-send-email-arve@android.com> References: <1271984938-13920-1-git-send-email-arve@android.com> <1271984938-13920-2-git-send-email-arve@android.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7532 Lines: 246 Add a misc device, "suspend_blocker", that allows user-space processes to block auto suspend. The device has ioctls to create a suspend_blocker, and to block and unblock suspend. To delete the suspend_blocker, close the device. Signed-off-by: Arve Hjønnevåg --- Documentation/power/suspend-blockers.txt | 17 ++++ include/linux/suspend_block_dev.h | 25 ++++++ kernel/power/Kconfig | 9 ++ kernel/power/Makefile | 1 + kernel/power/user_suspend_blocker.c | 128 ++++++++++++++++++++++++++++++ 5 files changed, 180 insertions(+), 0 deletions(-) create mode 100644 include/linux/suspend_block_dev.h create mode 100644 kernel/power/user_suspend_blocker.c diff --git a/Documentation/power/suspend-blockers.txt b/Documentation/power/suspend-blockers.txt index 1c48514..877bd8c 100644 --- a/Documentation/power/suspend-blockers.txt +++ b/Documentation/power/suspend-blockers.txt @@ -95,3 +95,20 @@ if (list_empty(&state->pending_work)) else suspend_block(&state->suspend_blocker); +User-space API +============== + +To create a suspend_blocker from user-space, open the suspend_blocker device: + fd = open("/dev/suspend_blocker", O_RDWR | O_CLOEXEC); +then call: + ioctl(fd, SUSPEND_BLOCKER_IOCTL_INIT(strlen(name)), name); + +To activate a suspend_blocker call: + ioctl(fd, SUSPEND_BLOCKER_IOCTL_BLOCK); + +To unblock call: + ioctl(fd, SUSPEND_BLOCKER_IOCTL_UNBLOCK); + +To destroy the suspend_blocker, close the device: + close(fd); + diff --git a/include/linux/suspend_block_dev.h b/include/linux/suspend_block_dev.h new file mode 100644 index 0000000..24bc5c7 --- /dev/null +++ b/include/linux/suspend_block_dev.h @@ -0,0 +1,25 @@ +/* include/linux/suspend_block_dev.h + * + * Copyright (C) 2009 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + * + */ + +#ifndef _LINUX_SUSPEND_BLOCK_DEV_H +#define _LINUX_SUSPEND_BLOCK_DEV_H + +#include + +#define SUSPEND_BLOCKER_IOCTL_INIT(len) _IOC(_IOC_WRITE, 's', 0, len) +#define SUSPEND_BLOCKER_IOCTL_BLOCK _IO('s', 1) +#define SUSPEND_BLOCKER_IOCTL_UNBLOCK _IO('s', 2) + +#endif diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index f8fa246..1ac50ee 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -141,6 +141,15 @@ config SUSPEND_BLOCKERS state through /sys/power/state, the requested sleep state will be entered when no suspend blockers are active. +config USER_SUSPEND_BLOCKERS + bool "Userspace suspend blockers" + depends on SUSPEND_BLOCKERS + default y + ---help--- + User-space suspend block api. Creates a misc device with ioctls + to create, block and unblock a suspend_blocker. The suspend_blocker + will be deleted when the device is closed. + config HIBERNATION_NVS bool diff --git a/kernel/power/Makefile b/kernel/power/Makefile index f570801..80086c6 100644 --- a/kernel/power/Makefile +++ b/kernel/power/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_PM_SLEEP) += console.o obj-$(CONFIG_FREEZER) += process.o obj-$(CONFIG_SUSPEND) += suspend.o obj-$(CONFIG_SUSPEND_BLOCKERS) += suspend_blocker.o +obj-$(CONFIG_USER_SUSPEND_BLOCKERS) += user_suspend_blocker.o obj-$(CONFIG_PM_TEST_SUSPEND) += suspend_test.o obj-$(CONFIG_HIBERNATION) += hibernate.o snapshot.o swap.o user.o obj-$(CONFIG_HIBERNATION_NVS) += hibernate_nvs.o diff --git a/kernel/power/user_suspend_blocker.c b/kernel/power/user_suspend_blocker.c new file mode 100644 index 0000000..a9be6f4 --- /dev/null +++ b/kernel/power/user_suspend_blocker.c @@ -0,0 +1,128 @@ +/* kernel/power/user_suspend_block.c + * + * Copyright (C) 2009-2010 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + * + */ + +#include +#include +#include +#include +#include +#include +#include + +enum { + DEBUG_FAILURE = BIT(0), +}; +static int debug_mask = DEBUG_FAILURE; +module_param_named(debug_mask, debug_mask, int, S_IRUGO | S_IWUSR | S_IWGRP); + +static DEFINE_MUTEX(ioctl_lock); + +struct user_suspend_blocker { + struct suspend_blocker blocker; + char name[0]; +}; + +static int create_user_suspend_blocker(struct file *file, void __user *name, + size_t name_len) +{ + struct user_suspend_blocker *bl; + if (file->private_data) + return -EBUSY; + if (name_len > NAME_MAX) + return -ENAMETOOLONG; + bl = kzalloc(sizeof(*bl) + name_len + 1, GFP_KERNEL); + if (!bl) + return -ENOMEM; + if (copy_from_user(bl->name, name, name_len)) + goto err_fault; + suspend_blocker_init(&bl->blocker, bl->name); + file->private_data = bl; + return 0; + +err_fault: + kfree(bl); + return -EFAULT; +} + +static long user_suspend_blocker_ioctl(struct file *file, unsigned int cmd, + unsigned long _arg) +{ + void __user *arg = (void __user *)_arg; + struct user_suspend_blocker *bl; + long ret; + + mutex_lock(&ioctl_lock); + if ((cmd & ~IOCSIZE_MASK) == SUSPEND_BLOCKER_IOCTL_INIT(0)) { + ret = create_user_suspend_blocker(file, arg, _IOC_SIZE(cmd)); + goto done; + } + bl = file->private_data; + if (!bl) { + ret = -ENOENT; + goto done; + } + switch (cmd) { + case SUSPEND_BLOCKER_IOCTL_BLOCK: + suspend_block(&bl->blocker); + ret = 0; + break; + case SUSPEND_BLOCKER_IOCTL_UNBLOCK: + suspend_unblock(&bl->blocker); + ret = 0; + break; + default: + ret = -ENOTSUPP; + } +done: + if (ret && debug_mask & DEBUG_FAILURE) + pr_err("user_suspend_blocker_ioctl: cmd %x failed, %ld\n", + cmd, ret); + mutex_unlock(&ioctl_lock); + return ret; +} + +static int user_suspend_blocker_release(struct inode *inode, struct file *file) +{ + struct user_suspend_blocker *bl = file->private_data; + if (!bl) + return 0; + suspend_blocker_destroy(&bl->blocker); + kfree(bl); + return 0; +} + +const struct file_operations user_suspend_blocker_fops = { + .release = user_suspend_blocker_release, + .unlocked_ioctl = user_suspend_blocker_ioctl, +}; + +struct miscdevice user_suspend_blocker_device = { + .minor = MISC_DYNAMIC_MINOR, + .name = "suspend_blocker", + .fops = &user_suspend_blocker_fops, +}; + +static int __init user_suspend_blocker_init(void) +{ + return misc_register(&user_suspend_blocker_device); +} + +static void __exit user_suspend_blocker_exit(void) +{ + misc_deregister(&user_suspend_blocker_device); +} + +module_init(user_suspend_blocker_init); +module_exit(user_suspend_blocker_exit); -- 1.6.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/