From patchwork Fri Nov 29 11:31:31 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Paul Durrant X-Patchwork-Id: 11267031 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B7198930 for ; Fri, 29 Nov 2019 11:32:47 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 92FB820833 for ; Fri, 29 Nov 2019 11:32:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="AdSiDDee" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 92FB820833 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1iaeV1-0007sJ-K1; Fri, 29 Nov 2019 11:31:47 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1iaeV0-0007s4-9d for xen-devel@lists.xenproject.org; Fri, 29 Nov 2019 11:31:46 +0000 X-Inumbo-ID: d1845b82-129b-11ea-a3e3-12813bfff9fa Received: from smtp-fw-2101.amazon.com (unknown [72.21.196.25]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id d1845b82-129b-11ea-a3e3-12813bfff9fa; Fri, 29 Nov 2019 11:31:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1575027104; x=1606563104; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=mMhOHfzPWPTlT1F2YNHMoR0lHgdtufqIO3c7y6opQtU=; b=AdSiDDeeX1p0uLSk14CA3pK6BmTY3b0vpuEM5f2upXnFTCE0vmW8ja2H bYPk1RZ6d7bWXtHlTmKtGZwe5dAeK7QcXi8/w02p8UxqDUzG/XUq4WLl9 sWO3v46/kaxrhN3jcDg2wb1h/ssoFLpjydD3DTdb48pohFNejoSSX5izT Y=; IronPort-SDR: tCTMha4UmWWdKldyDrvAlDYY68CEDgb6gKIYIsC2/pdiXNN710kvSXEsC3MIFWRdVM2fK2ap+j uQsRzkoyT6Qg== X-IronPort-AV: E=Sophos;i="5.69,257,1571702400"; d="scan'208";a="6338463" Received: from iad6-co-svc-p1-lb1-vlan2.amazon.com (HELO email-inbound-relay-1a-67b371d8.us-east-1.amazon.com) ([10.124.125.2]) by smtp-border-fw-out-2101.iad2.amazon.com with ESMTP; 29 Nov 2019 11:31:41 +0000 Received: from EX13MTAUEA001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan3.iad.amazon.com [10.40.159.166]) by email-inbound-relay-1a-67b371d8.us-east-1.amazon.com (Postfix) with ESMTPS id CEE4EA1803; Fri, 29 Nov 2019 11:31:38 +0000 (UTC) Received: from EX13D32EUB003.ant.amazon.com (10.43.166.165) by EX13MTAUEA001.ant.amazon.com (10.43.61.82) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Fri, 29 Nov 2019 11:31:38 +0000 Received: from EX13MTAUWB001.ant.amazon.com (10.43.161.207) by EX13D32EUB003.ant.amazon.com (10.43.166.165) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Fri, 29 Nov 2019 11:31:37 +0000 Received: from u2f063a87eabd5f.cbg10.amazon.com (10.125.106.135) by mail-relay.amazon.com (10.43.161.249) with Microsoft SMTP Server id 15.0.1367.3 via Frontend Transport; Fri, 29 Nov 2019 11:31:34 +0000 From: Paul Durrant To: , , Date: Fri, 29 Nov 2019 11:31:31 +0000 Message-ID: <20191129113131.1954-1-pdurrant@amazon.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Precedence: Bulk Subject: [Xen-devel] [PATCH] xen-blkback: allow module to be cleanly unloaded X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Jens Axboe , Paul Durrant , =?utf-8?q?Roger_Pau_Monn=C3=A9?= , Konrad Rzeszutek Wilk Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Add a module_exit() to perform the necessary clean-up. Also add __module_get() and module_put() calls into xen_blkif_alloc() and xen_blkif_free() respectively to make sure an in-use module cannot be unloaded. Signed-off-by: Paul Durrant --- Cc: Konrad Rzeszutek Wilk Cc: "Roger Pau Monné" Cc: Jens Axboe --- drivers/block/xen-blkback/blkback.c | 8 ++++++++ drivers/block/xen-blkback/common.h | 3 +++ drivers/block/xen-blkback/xenbus.c | 15 +++++++++++++++ 3 files changed, 26 insertions(+) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index fd1e19f1a49f..e562a7e20c3c 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -1504,5 +1504,13 @@ static int __init xen_blkif_init(void) module_init(xen_blkif_init); +static void __exit xen_blkif_fini(void) +{ + xen_blkif_xenbus_fini(); + xen_blkif_interface_fini(); +} + +module_exit(xen_blkif_fini); + MODULE_LICENSE("Dual BSD/GPL"); MODULE_ALIAS("xen-backend:vbd"); diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h index 1d3002d773f7..49132b0adbbe 100644 --- a/drivers/block/xen-blkback/common.h +++ b/drivers/block/xen-blkback/common.h @@ -375,9 +375,12 @@ struct phys_req { struct block_device *bdev; blkif_sector_t sector_number; }; + int xen_blkif_interface_init(void); +void xen_blkif_interface_fini(void); int xen_blkif_xenbus_init(void); +void xen_blkif_xenbus_fini(void); irqreturn_t xen_blkif_be_int(int irq, void *dev_id); int xen_blkif_schedule(void *arg); diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index b90dbcd99c03..f948584fcf66 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -173,6 +173,8 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid) init_completion(&blkif->drain_complete); INIT_WORK(&blkif->free_work, xen_blkif_deferred_free); + __module_get(THIS_MODULE); + return blkif; } @@ -320,6 +322,8 @@ static void xen_blkif_free(struct xen_blkif *blkif) /* Make sure everything is drained before shutting down */ kmem_cache_free(xen_blkif_cachep, blkif); + + module_put(THIS_MODULE); } int __init xen_blkif_interface_init(void) @@ -333,6 +337,12 @@ int __init xen_blkif_interface_init(void) return 0; } +void xen_blkif_interface_fini(void) +{ + kmem_cache_destroy(xen_blkif_cachep); + xen_blkif_cachep = NULL; +} + /* * sysfs interface for VBD I/O requests */ @@ -1122,3 +1132,8 @@ int xen_blkif_xenbus_init(void) { return xenbus_register_backend(&xen_blkbk_driver); } + +void xen_blkif_xenbus_fini(void) +{ + xenbus_unregister_driver(&xen_blkbk_driver); +}