From nobody Sat Dec 28 03:28:51 2024 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 7D48E19EEBD; Mon, 9 Dec 2024 19:03:10 +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=1733770992; cv=none; b=ABpSpVIRxADkCNbHMN68wGU2HaFWbkqAfEA0z8XUJQ2QBbZ/e5QW2PMEpKDg78OOww8zQ1Upf4w/5fe/qY4CXfh9NxQx99NFcp7+RkpMEPupUnW/FCGrGcg7zWeYnQMKp0wbGCENP4tAxfX0bjO9NbBSVGdmEP3tGVCRRzk/MjY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733770992; c=relaxed/simple; bh=cb66V+as2dtg11ZepZuG+P+2i30nRAGI6mzTBhnTPXA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kxh40kzz7B4/bV2c11pwsBhWpGwDorsdP5AEa8m8bc3fKAwYDHclxHWQONKdbWkyXbU4JsNxhsL8k7+gCc0OsZtj3DJLxs9I3OFPx35SY0KHWlo8ngcw0BR6Zo8KLlOB0s8VFIyn2cvD2bP6TnQsPem3ABwTyxAZbrK99nsiUaY= 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=YoYD28m+; 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="YoYD28m+" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=codeweavers.com; s=s1; h=Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=dxkbSXM8+NdWh2nFtUMzBGZ7TbW5+CQh4cSgojs2gxI=; b=YoYD28m+ITVR0ID16a0s5ziDNj C2r92jaJxOYrUCfxRgrN5k4RwWqwVxshFCpBhkhKFzv3uBZa7YBo6Qif8yvN2d2E8fUqGo4NnA4nu /gzBtREwXpEzYwRmV+zeoXeoErzVwjB0ZIUalbEFeRBV5KcANT1vxpbadBbHvxZu4w5unoM/r5z6s cw+rW4NHSMwi+EgolbtPm8/MC0FfJVTIg6jrfjn/vo/to3vLhlFa04mKwUkyTX3JkC/w9EUGotpUG OXo2xKqXfbGYY61iVhbzZbKQTV4qvedxP9n+y+CwwcAVmJJaiIu4JWAvU9YCPO4uE7XkhVAwuG0Xt gEYB12Tg==; 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 1tKiyY-001Gd5-15; Mon, 09 Dec 2024 12:59:22 -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=20Almeida?= , Wolfram Sang , Arkadiusz Hiler , Peter Zijlstra , Andy Lutomirski , linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, Randy Dunlap , Ingo Molnar , Will Deacon , Waiman Long , Boqun Feng , Elizabeth Figura Subject: [PATCH v6 03/28] ntsync: Introduce NTSYNC_IOC_CREATE_MUTEX. Date: Mon, 9 Dec 2024 12:58:39 -0600 Message-ID: <20241209185904.507350-4-zfigura@codeweavers.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241209185904.507350-1-zfigura@codeweavers.com> References: <20241209185904.507350-1-zfigura@codeweavers.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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. Th= e OS records the thread which acquired it. 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 p= assed 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 | 77 +++++++++++++++++++++++++++++++++++-- include/uapi/linux/ntsync.h | 10 ++++- 2 files changed, 83 insertions(+), 4 deletions(-) diff --git a/drivers/misc/ntsync.c b/drivers/misc/ntsync.c index 0f4da571fa33..30c0bbb442da 100644 --- a/drivers/misc/ntsync.c +++ b/drivers/misc/ntsync.c @@ -25,6 +25,7 @@ =20 enum ntsync_type { NTSYNC_TYPE_SEM, + NTSYNC_TYPE_MUTEX, }; =20 /* @@ -55,6 +56,10 @@ struct ntsync_obj { __u32 count; __u32 max; } sem; + struct { + __u32 count; + pid_t owner; + } mutex; } u; =20 /* @@ -92,6 +97,7 @@ struct ntsync_q_entry { =20 struct ntsync_q { struct task_struct *task; + __u32 owner; =20 /* * Protected via atomic_try_cmpxchg(). Only the thread that wins the @@ -214,13 +220,17 @@ static void ntsync_unlock_obj(struct ntsync_device *d= ev, struct ntsync_obj *obj, ((lockdep_is_held(&(obj)->dev->wait_all_lock) !=3D LOCK_STATE_NOT= _HELD) && \ (obj)->dev_locked)) =20 -static bool is_signaled(struct ntsync_obj *obj) +static bool is_signaled(struct ntsync_obj *obj, __u32 owner) { ntsync_assert_held(obj); =20 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 !=3D owner) + return false; + return obj->u.mutex.count < UINT_MAX; } =20 WARN(1, "bad object type %#x\n", obj->type); @@ -250,7 +260,7 @@ static void try_wake_all(struct ntsync_device *dev, str= uct ntsync_q *q, } =20 for (i =3D 0; i < count; i++) { - if (!is_signaled(q->entries[i].obj)) { + if (!is_signaled(q->entries[i].obj, q->owner)) { can_wake =3D false; break; } @@ -264,6 +274,10 @@ static void try_wake_all(struct ntsync_device *dev, st= ruct ntsync_q *q, case NTSYNC_TYPE_SEM: obj->u.sem.count--; break; + case NTSYNC_TYPE_MUTEX: + obj->u.mutex.count++; + obj->u.mutex.owner =3D q->owner; + break; } } wake_up_process(q->task); @@ -307,6 +321,30 @@ static void try_wake_any_sem(struct ntsync_obj *sem) } } =20 +static void try_wake_any_mutex(struct ntsync_obj *mutex) +{ + struct ntsync_q_entry *entry; + + ntsync_assert_held(mutex); + lockdep_assert(mutex->type =3D=3D NTSYNC_TYPE_MUTEX); + + list_for_each_entry(entry, &mutex->any_waiters, node) { + struct ntsync_q *q =3D entry->q; + int signaled =3D -1; + + if (mutex->u.mutex.count =3D=3D UINT_MAX) + break; + if (mutex->u.mutex.owner && mutex->u.mutex.owner !=3D q->owner) + continue; + + if (atomic_try_cmpxchg(&q->signaled, &signaled, entry->index)) { + mutex->u.mutex.count++; + mutex->u.mutex.owner =3D q->owner; + wake_up_process(q->task); + } + } +} + /* * Actually change the semaphore state, returning -EOVERFLOW if it is made * invalid. @@ -454,6 +492,33 @@ static int ntsync_create_sem(struct ntsync_device *dev= , void __user *argp) return put_user(fd, &user_args->sem); } =20 +static int ntsync_create_mutex(struct ntsync_device *dev, void __user *arg= p) +{ + struct ntsync_mutex_args __user *user_args =3D 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 !=3D !args.count) + return -EINVAL; + + mutex =3D ntsync_alloc_obj(dev, NTSYNC_TYPE_MUTEX); + if (!mutex) + return -ENOMEM; + mutex->u.mutex.count =3D args.count; + mutex->u.mutex.owner =3D args.owner; + fd =3D 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 =3D fget(fd); @@ -523,7 +588,7 @@ static int setup_wait(struct ntsync_device *dev, struct ntsync_q *q; __u32 i, j; =20 - if (args->pad[0] || args->pad[1] || args->pad[2] || (args->flags & ~NTSYN= C_WAIT_REALTIME)) + if (args->pad[0] || args->pad[1] || (args->flags & ~NTSYNC_WAIT_REALTIME)) return -EINVAL; =20 if (args->count > NTSYNC_MAX_WAIT_COUNT) @@ -537,6 +602,7 @@ static int setup_wait(struct ntsync_device *dev, if (!q) return -ENOMEM; q->task =3D current; + q->owner =3D args->owner; atomic_set(&q->signaled, -1); q->all =3D all; q->count =3D count; @@ -579,6 +645,9 @@ 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; } } =20 @@ -768,6 +837,8 @@ static long ntsync_char_ioctl(struct file *file, unsign= ed int cmd, void __user *argp =3D (void __user *)parm; =20 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 addf187b1573..d5e5a2fbcb4d 100644 --- a/include/uapi/linux/ntsync.h +++ b/include/uapi/linux/ntsync.h @@ -16,6 +16,12 @@ struct ntsync_sem_args { __u32 max; }; =20 +struct ntsync_mutex_args { + __u32 mutex; + __u32 owner; + __u32 count; +}; + #define NTSYNC_WAIT_REALTIME 0x1 =20 struct ntsync_wait_args { @@ -24,7 +30,8 @@ struct ntsync_wait_args { __u32 count; __u32 index; __u32 flags; - __u32 pad[3]; + __u32 owner; + __u32 pad[2]; }; =20 #define NTSYNC_MAX_WAIT_COUNT 64 @@ -32,6 +39,7 @@ 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) =20 #define NTSYNC_IOC_SEM_POST _IOWR('N', 0x81, __u32) =20 --=20 2.45.2