From patchwork Tue Feb 15 09:45:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12746770 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0BCBBC4332F for ; Tue, 15 Feb 2022 09:45:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234748AbiBOJpj (ORCPT ); Tue, 15 Feb 2022 04:45:39 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:49104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233306AbiBOJpi (ORCPT ); Tue, 15 Feb 2022 04:45:38 -0500 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49D3AE61E1; Tue, 15 Feb 2022 01:45:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; 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; bh=M/k0M/YRhjeaZRYqG7d2lMZ9R/cEqFwtMhYSGaXiMyo=; b=rjNE9tRjeLvNV+viXnfwqakzHK 0yyDr6Ea7RXNCCA00xMGq6MPjjMjFZ3b63bPyWlIMpoQga/k/pYqL4gnRgLnqEPLY4sgDiovPhXb9 lzSu+OVAg6R/O/Ew//V8V3H/sKk7iQ14RsSYuqcHx9GcSqGtuqnhcP7Em8eas/D54uhfjy25lKcRt Al5V9hyDNbaFkwB270BYoq8i8na2/GVZqAs34a7LvAaawWiS5BQAUnBGBdFOfb+TtlUQY1y3GWwwb ox7DrhHX7DvTJAfeBM0Cuuz5RRqgDhwBSUQ6i5b75sLsNfDUe/gnVQou6uEroDCdl4apPA0ako8vq yIBkEvjw==; Received: from [2001:4bb8:184:543c:6bdf:22f4:7f0a:fe97] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nJuOd-00260q-UE; Tue, 15 Feb 2022 09:45:20 +0000 From: Christoph Hellwig To: Jens Axboe Cc: "Michael S. Tsirkin" , Jason Wang , Paolo Bonzini , Stefan Hajnoczi , Maxim Levitsky , Alex Dubov , Ulf Hansson , linux-block@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-mmc@vger.kernel.org Subject: [PATCH 1/5] block: add a ->free_disk method Date: Tue, 15 Feb 2022 10:45:10 +0100 Message-Id: <20220215094514.3828912-2-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220215094514.3828912-1-hch@lst.de> References: <20220215094514.3828912-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org Add a method to notify the driver that the gendisk is about to be freed. This allows drivers to tie the lifetime of their private data to that of the gendisk and thus deal with device removal races without expensive synchronization and boilerplate code. A new flag is added so that ->free_disk is only called after a successful call to add_disk, which significantly simplifies the error handling path during probing. Signed-off-by: Christoph Hellwig --- block/genhd.c | 5 +++++ include/linux/blkdev.h | 2 ++ 2 files changed, 7 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index 9589d1d59afab..e351fac41bf25 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -526,6 +526,7 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk, disk_update_readahead(disk); disk_add_events(disk); + set_bit(GD_ADDED, &disk->state); return 0; out_unregister_bdi: @@ -1119,6 +1120,10 @@ static void disk_release(struct device *dev) xa_destroy(&disk->part_tbl); disk->queue->disk = NULL; blk_put_queue(disk->queue); + + if (test_bit(GD_ADDED, &disk->state) && disk->fops->free_disk) + disk->fops->free_disk(disk); + iput(disk->part0->bd_inode); /* frees the disk */ } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 3bfc75a2a4509..f757f9c2871f8 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -146,6 +146,7 @@ struct gendisk { #define GD_READ_ONLY 1 #define GD_DEAD 2 #define GD_NATIVE_CAPACITY 3 +#define GD_ADDED 4 struct mutex open_mutex; /* open/close mutex */ unsigned open_partitions; /* number of open partitions */ @@ -1464,6 +1465,7 @@ struct block_device_operations { void (*unlock_native_capacity) (struct gendisk *); int (*getgeo)(struct block_device *, struct hd_geometry *); int (*set_read_only)(struct block_device *bdev, bool ro); + void (*free_disk)(struct gendisk *disk); /* this callback is with swap_lock and sometimes page table lock held */ void (*swap_slot_free_notify) (struct block_device *, unsigned long); int (*report_zones)(struct gendisk *, sector_t sector,