From patchwork Mon Feb 19 22:38:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elizabeth Figura X-Patchwork-Id: 13563174 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 E128954BC4; Mon, 19 Feb 2024 22:39:35 +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=1708382380; cv=none; b=VRTysZZFbnYFrk/jrmQLnBHHx9W930mzP46K+uwAfUQfiDCVpg7aXxJ10Fzo6/Xdxbt5Kmm3W24mfl51T8zpkq20YHSbJ+uG1YaJ9egU8CNn0L3li3duGmC0yyHNHc9Axe5boWaXxCsEZqsSJ6098AhZbOsYiTQg0iRovtPVmYQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708382380; c=relaxed/simple; bh=g9RWuZtC7he717kJRvybOS/DWVR3tzwH5luwapkwbpQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MR2C6EtgD1UYvUR+mDs8erF3u89pXz8Ctk5cPbEKSviLAJS1gKKV7Ajd3Ewfac2q/yR723APm2mJlZ1MHTrJ54DuZfacrg+npJZWTr7w91/PxTqcb8SeEMQ915pAJfD56jxBOOVuhZSUPfB4CsajbnVRLMcfJkLgw2WaEEbhRu4= 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=ifEIv+bo; 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="ifEIv+bo" 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=LJ9zQbFRAXQYsgUiGqfhlDGHUr76nq8+nalQeidRqak=; b=ifEIv+boKsWtoQmogdKRmSePIl KwwPTo5N6d7yrFdAdeJKcXfalTIP97y7fYRIGDoXcQTS7QFJ4IWfKY0kJCDqMhbnoH+6YIa9EJVwA 9ud5kSZEuubSPcZ3wblAH2jPr9XrNUbVmI7y/gFFvdBWRxsRpXtLDc/+IJEoKB1av4lDuHhPIjgGn pyZmaO0UkdNwh7D8NuG7Ydk56oOgHEHZrBQu27BY09ZUsUqkYukNuzsfXN79SAcmQICzd+gTorPMK nc/rRmFLQUz7poiSJcUu0whht9GcKWc3izHRhoyXJRHXm8Bzdx9Y1ymVRXMh23uD0w5kLytxJiCNS nn4t8uSA==; 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 1rcCIL-0037Oz-2d; Mon, 19 Feb 2024 16:39:29 -0600 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 v2 06/31] ntsync: Introduce NTSYNC_IOC_CREATE_MUTEX. Date: Mon, 19 Feb 2024 16:38:08 -0600 Message-ID: <20240219223833.95710-7-zfigura@codeweavers.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240219223833.95710-1-zfigura@codeweavers.com> References: <20240219223833.95710-1-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 NtCreateMutant(). An NT mutex is recursive, with a 32-bit recursion counter. When acquired via NtWaitForMultipleObjects(), the recursion counter is incremented by one. The OS records the thread which acquired it. However, in order to keep this driver self-contained, the owning thread ID is managed by user-space, and passed as a parameter to all relevant ioctls. The initial owner and recursion count, if any, are specified when the mutex is created. Signed-off-by: Elizabeth Figura --- drivers/misc/ntsync.c | 67 +++++++++++++++++++++++++++++++++++++ include/uapi/linux/ntsync.h | 7 ++++ 2 files changed, 74 insertions(+) diff --git a/drivers/misc/ntsync.c b/drivers/misc/ntsync.c index d5759e9a3a8e..6f7086d0440a 100644 --- a/drivers/misc/ntsync.c +++ b/drivers/misc/ntsync.c @@ -24,6 +24,7 @@ enum ntsync_type { NTSYNC_TYPE_SEM, + NTSYNC_TYPE_MUTEX, }; /* @@ -53,6 +54,10 @@ struct ntsync_obj { __u32 count; __u32 max; } sem; + struct { + __u32 count; + __u32 owner; + } mutex; } u; /* @@ -132,6 +137,10 @@ static bool is_signaled(struct ntsync_obj *obj, __u32 owner) switch (obj->type) { case NTSYNC_TYPE_SEM: return !!obj->u.sem.count; + case NTSYNC_TYPE_MUTEX: + if (obj->u.mutex.owner && obj->u.mutex.owner != owner) + return false; + return obj->u.mutex.count < UINT_MAX; } WARN(1, "bad object type %#x\n", obj->type); @@ -174,6 +183,10 @@ static void try_wake_all(struct ntsync_device *dev, struct ntsync_q *q, case NTSYNC_TYPE_SEM: obj->u.sem.count--; break; + case NTSYNC_TYPE_MUTEX: + obj->u.mutex.count++; + obj->u.mutex.owner = q->owner; + break; } } wake_up_process(q->task); @@ -215,6 +228,28 @@ static void try_wake_any_sem(struct ntsync_obj *sem) } } +static void try_wake_any_mutex(struct ntsync_obj *mutex) +{ + struct ntsync_q_entry *entry; + + lockdep_assert_held(&mutex->lock); + + list_for_each_entry(entry, &mutex->any_waiters, node) { + struct ntsync_q *q = entry->q; + + if (mutex->u.mutex.count == UINT_MAX) + break; + if (mutex->u.mutex.owner && mutex->u.mutex.owner != q->owner) + continue; + + if (atomic_cmpxchg(&q->signaled, -1, entry->index) == -1) { + mutex->u.mutex.count++; + mutex->u.mutex.owner = q->owner; + wake_up_process(q->task); + } + } +} + /* * Actually change the semaphore state, returning -EOVERFLOW if it is made * invalid. @@ -374,6 +409,33 @@ static int ntsync_create_sem(struct ntsync_device *dev, void __user *argp) return put_user(fd, &user_args->sem); } +static int ntsync_create_mutex(struct ntsync_device *dev, void __user *argp) +{ + struct ntsync_mutex_args __user *user_args = argp; + struct ntsync_mutex_args args; + struct ntsync_obj *mutex; + int fd; + + if (copy_from_user(&args, argp, sizeof(args))) + return -EFAULT; + + if (!args.owner != !args.count) + return -EINVAL; + + mutex = ntsync_alloc_obj(dev, NTSYNC_TYPE_MUTEX); + if (!mutex) + return -ENOMEM; + mutex->u.mutex.count = args.count; + mutex->u.mutex.owner = args.owner; + fd = ntsync_obj_get_fd(mutex); + if (fd < 0) { + kfree(mutex); + return fd; + } + + return put_user(fd, &user_args->mutex); +} + static struct ntsync_obj *get_obj(struct ntsync_device *dev, int fd) { struct file *file = fget(fd); @@ -493,6 +555,9 @@ static void try_wake_any_obj(struct ntsync_obj *obj) case NTSYNC_TYPE_SEM: try_wake_any_sem(obj); break; + case NTSYNC_TYPE_MUTEX: + try_wake_any_mutex(obj); + break; } } @@ -681,6 +746,8 @@ static long ntsync_char_ioctl(struct file *file, unsigned int cmd, void __user *argp = (void __user *)parm; switch (cmd) { + case NTSYNC_IOC_CREATE_MUTEX: + return ntsync_create_mutex(dev, argp); case NTSYNC_IOC_CREATE_SEM: return ntsync_create_sem(dev, argp); case NTSYNC_IOC_WAIT_ALL: diff --git a/include/uapi/linux/ntsync.h b/include/uapi/linux/ntsync.h index 19c37e27a4f8..8ac9d419c360 100644 --- a/include/uapi/linux/ntsync.h +++ b/include/uapi/linux/ntsync.h @@ -16,6 +16,12 @@ struct ntsync_sem_args { __u32 max; }; +struct ntsync_mutex_args { + __u32 mutex; + __u32 owner; + __u32 count; +}; + struct ntsync_wait_args { __u64 timeout; __u64 objs; @@ -30,6 +36,7 @@ struct ntsync_wait_args { #define NTSYNC_IOC_CREATE_SEM _IOWR('N', 0x80, struct ntsync_sem_args) #define NTSYNC_IOC_WAIT_ANY _IOWR('N', 0x82, struct ntsync_wait_args) #define NTSYNC_IOC_WAIT_ALL _IOWR('N', 0x83, 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)