From patchwork Fri Mar 29 00:05:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elizabeth Figura X-Patchwork-Id: 784316 Received: from mail.codeweavers.com (mail.codeweavers.com [4.36.192.163]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7328D101E2; Fri, 29 Mar 2024 00:23:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=4.36.192.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711671818; cv=none; b=SM9HTM2RLx4wukhl8zFJMLNEjcSW8cSvt1H0VWXJ7WhcL6xmiLC1tXOdoyP0OJm7HnOPWNEO1kCntYPgjvhcLwUnh8bU8yAcN2rppv07uCjZJiHBL/ryHhDN+iM9oxsnmPGoj760TcWRlz1i5rfsMaKyi69bm3yqDQwDhs1no0Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711671818; c=relaxed/simple; bh=ZpmXc+jo5vS+063ZnNDqudgU3KZ6+0rnGyQbe6US0Lg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=urhXmkhSWGN+gZ2S8/aMFEPW8Wvhx9nmeftkmMEMmh12DEjvgMeU65yQ77ersx99ziQfrGaEJjhJkRXh1rDrg+GlkDRoFAlcXoih/S3f2ZbWS1iSd5d3+NMVpghn1m1R3ddiwVUjcyrxDTChRyn1Qlk6xq/1F+tO+LrBgWvxgVs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=codeweavers.com; spf=pass smtp.mailfrom=codeweavers.com; dkim=pass (2048-bit key) header.d=codeweavers.com header.i=@codeweavers.com header.b=TYpTxjOD; arc=none smtp.client-ip=4.36.192.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=codeweavers.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=codeweavers.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=codeweavers.com header.i=@codeweavers.com header.b="TYpTxjOD" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=codeweavers.com; s=s1; h=Message-ID:Date:Subject:Cc:To:From:Sender; bh=W+i/4Tm5fzFDs0G6pROKKJsrD/qfJkZXPY0XHK3LoIs=; b=TYpTxjODBC777Wsva+xH5yvFw7 0aatHpZnaPsCgMBGpqk/HmtRj4XI6hW+r13raO2TvVN0EA4lPn20h5nxLSnr4tKARd51HUcSwRmrF cmnRLwUDjpXVy4IKisau0W/k+vX4Jg2nQJdUY6kLIYFBCwroyabCq03lglGpIChw6YzOH02UObIe2 fZfo6+fDIS6SEDOiY7imVSCFtEjLczfpmdQATLBkSRvB9b+Zh8R//c5wwirsTZbgg4eqXXphZvOmY b6qtmnIpzYU97N2SVrkXJPb0y//RqBy92hkwfCF7fDxg2hyGpTBke/bIqP7x/xNBtZGW3AcjBA6vl AaRqLjKg==; Received: from cw137ip160.mn.codeweavers.com ([10.69.137.160] helo=camazotz.mn.codeweavers.com) by mail.codeweavers.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1rpzlN-000iik-0N; Thu, 28 Mar 2024 19:06:29 -0500 From: Elizabeth Figura To: Arnd Bergmann , Greg Kroah-Hartman , Jonathan Corbet , Shuah Khan Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, wine-devel@winehq.org, =?utf-8?q?Andr=C3=A9_Almeida?= , Wolfram Sang , Arkadiusz Hiler , Peter Zijlstra , Andy Lutomirski , linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, Randy Dunlap , Elizabeth Figura Subject: [PATCH v3 07/30] ntsync: Introduce NTSYNC_IOC_MUTEX_UNLOCK. Date: Thu, 28 Mar 2024 19:05:58 -0500 Message-ID: <20240329000621.148791-8-zfigura@codeweavers.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240329000621.148791-1-zfigura@codeweavers.com> References: <20240329000621.148791-1-zfigura@codeweavers.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This corresponds to the NT syscall NtReleaseMutant(). This syscall decrements the mutex's recursion count by one, and returns the previous value. If the mutex is not owned by the given owner ID, the function instead fails and returns -EPERM. Signed-off-by: Elizabeth Figura --- drivers/misc/ntsync.c | 64 +++++++++++++++++++++++++++++++++++++ include/uapi/linux/ntsync.h | 1 + 2 files changed, 65 insertions(+) diff --git a/drivers/misc/ntsync.c b/drivers/misc/ntsync.c index 173513aeeacc..f7911ef78d5b 100644 --- a/drivers/misc/ntsync.c +++ b/drivers/misc/ntsync.c @@ -315,6 +315,68 @@ static int ntsync_sem_post(struct ntsync_obj *sem, void __user *argp) return ret; } +/* + * Actually change the mutex state, returning -EPERM if not the owner. + */ +static int unlock_mutex_state(struct ntsync_obj *mutex, + const struct ntsync_mutex_args *args) +{ + lockdep_assert_held(&mutex->lock); + + if (mutex->u.mutex.owner != args->owner) + return -EPERM; + + if (!--mutex->u.mutex.count) + mutex->u.mutex.owner = 0; + return 0; +} + +static int ntsync_mutex_unlock(struct ntsync_obj *mutex, void __user *argp) +{ + struct ntsync_mutex_args __user *user_args = argp; + struct ntsync_device *dev = mutex->dev; + struct ntsync_mutex_args args; + __u32 prev_count; + int ret; + + if (copy_from_user(&args, argp, sizeof(args))) + return -EFAULT; + if (!args.owner) + return -EINVAL; + + if (mutex->type != NTSYNC_TYPE_MUTEX) + return -EINVAL; + + if (atomic_read(&mutex->all_hint) > 0) { + spin_lock(&dev->wait_all_lock); + spin_lock_nest_lock(&mutex->lock, &dev->wait_all_lock); + + prev_count = mutex->u.mutex.count; + ret = unlock_mutex_state(mutex, &args); + if (!ret) { + try_wake_all_obj(dev, mutex); + try_wake_any_mutex(mutex); + } + + spin_unlock(&mutex->lock); + spin_unlock(&dev->wait_all_lock); + } else { + spin_lock(&mutex->lock); + + prev_count = mutex->u.mutex.count; + ret = unlock_mutex_state(mutex, &args); + if (!ret) + try_wake_any_mutex(mutex); + + spin_unlock(&mutex->lock); + } + + if (!ret && put_user(prev_count, &user_args->count)) + ret = -EFAULT; + + return ret; +} + static int ntsync_obj_release(struct inode *inode, struct file *file) { struct ntsync_obj *obj = file->private_data; @@ -334,6 +396,8 @@ static long ntsync_obj_ioctl(struct file *file, unsigned int cmd, switch (cmd) { case NTSYNC_IOC_SEM_POST: return ntsync_sem_post(obj, argp); + case NTSYNC_IOC_MUTEX_UNLOCK: + return ntsync_mutex_unlock(obj, argp); default: return -ENOIOCTLCMD; } diff --git a/include/uapi/linux/ntsync.h b/include/uapi/linux/ntsync.h index cd7841cdba49..fa2c9f638d77 100644 --- a/include/uapi/linux/ntsync.h +++ b/include/uapi/linux/ntsync.h @@ -43,5 +43,6 @@ struct ntsync_wait_args { #define NTSYNC_IOC_CREATE_MUTEX _IOWR('N', 0x84, struct ntsync_sem_args) #define NTSYNC_IOC_SEM_POST _IOWR('N', 0x81, __u32) +#define NTSYNC_IOC_MUTEX_UNLOCK _IOWR('N', 0x85, struct ntsync_mutex_args) #endif