From nobody Mon Dec 1 23:33:19 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 03F9F28727A for ; Mon, 1 Dec 2025 21:43:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764625427; cv=none; b=AirGw+Xqs+/hDTnwQhBxVJGXxZreryWjemUIJkd5Yd/RftxDRMLCjBewxqTNc2+3wvm5XGdbZWmm9NWlJsFbY+VGu+2wL1a9HkJe++577BQMe1bdfZ5t+J7RgBs9NNLTMZaTg40l4TMcTZPsHJ2DGtirAMW7xmsXVOJJVsXrFHE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764625427; c=relaxed/simple; bh=NqAD7IKNmEKH9tDaD4XtjDhDUpCRgB85D8rfNscxioY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mwIrTwIcX/j2+zCQedSMDA/1/wPfvQW+FnUP9enSS7YHmxGgLwE70PlopLyWdVd6yZOk7LxnINZw5UQRpv/A44nRSwRdItXp7DjP3WdQEaIBlJ/q7+PKY0s7RhfoP1bDIsj2LFRBuFo/ttfCPJsGLf+fnbw1DQrmzZ88jtq3sFM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Uwaf86gP; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Uwaf86gP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1764625425; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tmEzslKSkhmC0gLB9i+o3Qufbcn1D02jCo9kyVUqdsk=; b=Uwaf86gPuYM42tuzBPXA7K+xYlLitW9R70AsnmvssM1z6uZJRyTFvQBPi5vNFHxOtDeF+O jOyWgOAiXP+EHY4HWtnmIVE3MicywvpWU+M5b8H3a6cGa3oyfbLobAf2AdlU3pwFGR+/zM 1DxTaCSwQfmcs6pxp8qApoXYXd6iFRc= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-296-pvHD_HxaPw-VDLFQazgHzw-1; Mon, 01 Dec 2025 16:43:41 -0500 X-MC-Unique: pvHD_HxaPw-VDLFQazgHzw-1 X-Mimecast-MFC-AGG-ID: pvHD_HxaPw-VDLFQazgHzw_1764625419 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1B9A719560A1; Mon, 1 Dec 2025 21:43:39 +0000 (UTC) Received: from localhost (unknown [10.2.16.172]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 8BCA71956095; Mon, 1 Dec 2025 21:43:38 +0000 (UTC) From: Stefan Hajnoczi To: linux-block@vger.kernel.org Cc: Christoph Hellwig , linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, "James E.J. Bottomley" , "Martin K. Petersen" , Keith Busch , Jens Axboe , Sagi Grimberg , Mike Christie , Krzysztof Kozlowski , linux-nvme@lists.infradead.org, Stefan Hajnoczi Subject: [PATCH v3 3/4] block: add IOC_PR_READ_KEYS ioctl Date: Mon, 1 Dec 2025 16:43:28 -0500 Message-ID: <20251201214329.933945-4-stefanha@redhat.com> In-Reply-To: <20251201214329.933945-1-stefanha@redhat.com> References: <20251201214329.933945-1-stefanha@redhat.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 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Content-Type: text/plain; charset="utf-8" Add a Persistent Reservations ioctl to read the list of currently registered reservation keys. This calls the pr_ops->read_keys() function that was previously added in commit c787f1baa503 ("block: Add PR callouts for read keys and reservation") but was only used by the in-kernel SCSI target so far. The IOC_PR_READ_KEYS ioctl is necessary so that userspace applications that rely on Persistent Reservations ioctls have a way of inspecting the current state. Cluster managers and validation tests need this functionality. Signed-off-by: Stefan Hajnoczi --- include/uapi/linux/pr.h | 7 ++++++ block/ioctl.c | 56 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 63 insertions(+) diff --git a/include/uapi/linux/pr.h b/include/uapi/linux/pr.h index d8126415966f3..fcb74eab92c80 100644 --- a/include/uapi/linux/pr.h +++ b/include/uapi/linux/pr.h @@ -56,6 +56,12 @@ struct pr_clear { __u32 __pad; }; =20 +struct pr_read_keys { + __u32 generation; + __u32 num_keys; + __u64 keys_ptr; +}; + #define PR_FL_IGNORE_KEY (1 << 0) /* ignore existing key */ =20 #define IOC_PR_REGISTER _IOW('p', 200, struct pr_registration) @@ -64,5 +70,6 @@ struct pr_clear { #define IOC_PR_PREEMPT _IOW('p', 203, struct pr_preempt) #define IOC_PR_PREEMPT_ABORT _IOW('p', 204, struct pr_preempt) #define IOC_PR_CLEAR _IOW('p', 205, struct pr_clear) +#define IOC_PR_READ_KEYS _IOWR('p', 206, struct pr_read_keys) =20 #endif /* _UAPI_PR_H */ diff --git a/block/ioctl.c b/block/ioctl.c index d7489a56b33c3..95ce9aa90bba2 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -423,6 +423,60 @@ static int blkdev_pr_clear(struct block_device *bdev, = blk_mode_t mode, return ops->pr_clear(bdev, c.key); } =20 +static int blkdev_pr_read_keys(struct block_device *bdev, blk_mode_t mode, + struct pr_read_keys __user *arg) +{ + const struct pr_ops *ops =3D bdev->bd_disk->fops->pr_ops; + struct pr_keys *keys_info; + struct pr_read_keys read_keys; + u64 __user *keys_ptr; + size_t keys_info_len; + size_t keys_copy_len; + int ret; + + if (!blkdev_pr_allowed(bdev, mode)) + return -EPERM; + if (!ops || !ops->pr_read_keys) + return -EOPNOTSUPP; + + if (copy_from_user(&read_keys, arg, sizeof(read_keys))) + return -EFAULT; + + keys_info_len =3D struct_size(keys_info, keys, read_keys.num_keys); + if (keys_info_len =3D=3D SIZE_MAX) + return -EINVAL; + + keys_info =3D kzalloc(keys_info_len, GFP_KERNEL); + if (!keys_info) + return -ENOMEM; + + keys_info->num_keys =3D read_keys.num_keys; + + ret =3D ops->pr_read_keys(bdev, keys_info); + if (ret) + goto out; + + /* Copy out individual keys */ + keys_ptr =3D u64_to_user_ptr(read_keys.keys_ptr); + keys_copy_len =3D min(read_keys.num_keys, keys_info->num_keys) * + sizeof(keys_info->keys[0]); + + if (copy_to_user(keys_ptr, keys_info->keys, keys_copy_len)) { + ret =3D -EFAULT; + goto out; + } + + /* Copy out the arg struct */ + read_keys.generation =3D keys_info->generation; + read_keys.num_keys =3D keys_info->num_keys; + + if (copy_to_user(arg, &read_keys, sizeof(read_keys))) + ret =3D -EFAULT; +out: + kfree(keys_info); + return ret; +} + static int blkdev_flushbuf(struct block_device *bdev, unsigned cmd, unsigned long arg) { @@ -644,6 +698,8 @@ static int blkdev_common_ioctl(struct block_device *bde= v, blk_mode_t mode, return blkdev_pr_preempt(bdev, mode, argp, true); case IOC_PR_CLEAR: return blkdev_pr_clear(bdev, mode, argp); + case IOC_PR_READ_KEYS: + return blkdev_pr_read_keys(bdev, mode, argp); default: return blk_get_meta_cap(bdev, cmd, argp); } --=20 2.52.0