From patchwork Mon Nov 16 14:57:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 324953 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2413C82545 for ; Mon, 16 Nov 2020 14:59:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99DC322263 for ; Mon, 16 Nov 2020 14:59:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="uXQm/yyI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730889AbgKPO7V (ORCPT ); Mon, 16 Nov 2020 09:59:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730846AbgKPO7S (ORCPT ); Mon, 16 Nov 2020 09:59:18 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01C12C0613D2; Mon, 16 Nov 2020 06:59:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=9MasGm4sRMlqjIfBzvyRbCzoZ9vCizFcPgSc5rhaRew=; b=uXQm/yyIiJQnYODeCv7tLBroh6 arXMrp0Tk+2mkvK5mlMoVYQZhqOzsPFVFoVsNhqaXKjdbjxT6ddIFdHimSsiofqQFd042iVeyoPjf kjJVvZC7dJvRJWgFk5vnXEzcfiS2wRI+9CAHzFb6PaF2pf3aK/Vv/y+iBA3+wNlveiknIb+cM4k72 sy6+79pc3yQnXdRLw5qP9MUrMQWCUQr94hrqb0BHYJRuZX0RRf1WPApUNdGnDYjJKsodIy93uSBGl mXFAo94CwxYf32WkNugPW9wMsBEd2E2lCs3nmZ+m6b8g/Nfawh6vTjWCNJv2VNFFCFBCwJLajvHZl HFZ0RH2Q==; Received: from [2001:4bb8:180:6600:255b:7def:a93:4a09] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kefyA-0003wx-DT; Mon, 16 Nov 2020 14:59:02 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Justin Sanders , Josef Bacik , Ilya Dryomov , Jack Wang , "Michael S. Tsirkin" , Jason Wang , Paolo Bonzini , Stefan Hajnoczi , Konrad Rzeszutek Wilk , =?utf-8?q?Roger_Pau_Monn=C3=A9?= , Minchan Kim , Mike Snitzer , Song Liu , "Martin K. Petersen" , dm-devel@redhat.com, linux-block@vger.kernel.org, drbd-dev@lists.linbit.com, nbd@other.debian.org, ceph-devel@vger.kernel.org, xen-devel@lists.xenproject.org, linux-raid@vger.kernel.org, linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org, Hannes Reinecke Subject: [PATCH 37/78] block: split block_class_lock Date: Mon, 16 Nov 2020 15:57:28 +0100 Message-Id: <20201116145809.410558-38-hch@lst.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201116145809.410558-1-hch@lst.de> References: <20201116145809.410558-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Split the block_class_lock mutex into one each to protect bdev_map and major_names. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke --- block/genhd.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-) diff --git a/block/genhd.c b/block/genhd.c index 482f7b89802010..2a20372756625e 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -25,7 +25,6 @@ #include "blk.h" -static DEFINE_MUTEX(block_class_lock); static struct kobject *block_depr; struct bdev_map { @@ -37,6 +36,7 @@ struct bdev_map { int (*lock)(dev_t, void *); void *data; } *bdev_map[255]; +static DEFINE_MUTEX(bdev_map_lock); /* for extended dynamic devt allocation, currently only one major is used */ #define NR_EXT_DEVT (1 << MINORBITS) @@ -400,6 +400,7 @@ static struct blk_major_name { int major; char name[16]; } *major_names[BLKDEV_MAJOR_HASH_SIZE]; +static DEFINE_MUTEX(major_names_lock); /* index in the above - for now: assume no multimajor ranges */ static inline int major_to_index(unsigned major) @@ -412,11 +413,11 @@ void blkdev_show(struct seq_file *seqf, off_t offset) { struct blk_major_name *dp; - mutex_lock(&block_class_lock); + mutex_lock(&major_names_lock); for (dp = major_names[major_to_index(offset)]; dp; dp = dp->next) if (dp->major == offset) seq_printf(seqf, "%3d %s\n", dp->major, dp->name); - mutex_unlock(&block_class_lock); + mutex_unlock(&major_names_lock); } #endif /* CONFIG_PROC_FS */ @@ -445,7 +446,7 @@ int register_blkdev(unsigned int major, const char *name) struct blk_major_name **n, *p; int index, ret = 0; - mutex_lock(&block_class_lock); + mutex_lock(&major_names_lock); /* temporary */ if (major == 0) { @@ -498,7 +499,7 @@ int register_blkdev(unsigned int major, const char *name) kfree(p); } out: - mutex_unlock(&block_class_lock); + mutex_unlock(&major_names_lock); return ret; } @@ -510,7 +511,7 @@ void unregister_blkdev(unsigned int major, const char *name) struct blk_major_name *p = NULL; int index = major_to_index(major); - mutex_lock(&block_class_lock); + mutex_lock(&major_names_lock); for (n = &major_names[index]; *n; n = &(*n)->next) if ((*n)->major == major) break; @@ -520,7 +521,7 @@ void unregister_blkdev(unsigned int major, const char *name) p = *n; *n = p->next; } - mutex_unlock(&block_class_lock); + mutex_unlock(&major_names_lock); kfree(p); } @@ -671,7 +672,7 @@ void blk_register_region(dev_t devt, unsigned long range, struct module *module, p->data = data; } - mutex_lock(&block_class_lock); + mutex_lock(&bdev_map_lock); for (i = 0, p -= n; i < n; i++, p++, index++) { struct bdev_map **s = &bdev_map[index % 255]; while (*s && (*s)->range < range) @@ -679,7 +680,7 @@ void blk_register_region(dev_t devt, unsigned long range, struct module *module, p->next = *s; *s = p; } - mutex_unlock(&block_class_lock); + mutex_unlock(&bdev_map_lock); } EXPORT_SYMBOL(blk_register_region); @@ -690,7 +691,7 @@ void blk_unregister_region(dev_t devt, unsigned long range) unsigned i; struct bdev_map *found = NULL; - mutex_lock(&block_class_lock); + mutex_lock(&bdev_map_lock); for (i = 0; i < min(n, 255u); i++, index++) { struct bdev_map **s; for (s = &bdev_map[index % 255]; *s; s = &(*s)->next) { @@ -703,7 +704,7 @@ void blk_unregister_region(dev_t devt, unsigned long range) } } } - mutex_unlock(&block_class_lock); + mutex_unlock(&bdev_map_lock); kfree(found); } EXPORT_SYMBOL(blk_unregister_region); @@ -1034,7 +1035,7 @@ static struct gendisk *lookup_gendisk(dev_t dev, int *partno) unsigned long best = ~0UL; retry: - mutex_lock(&block_class_lock); + mutex_lock(&bdev_map_lock); for (p = bdev_map[MAJOR(dev) % 255]; p; p = p->next) { struct kobject *(*probe)(dev_t, int *, void *); struct module *owner; @@ -1055,7 +1056,7 @@ static struct gendisk *lookup_gendisk(dev_t dev, int *partno) module_put(owner); continue; } - mutex_unlock(&block_class_lock); + mutex_unlock(&bdev_map_lock); kobj = probe(dev, partno, data); /* Currently ->owner protects _only_ ->probe() itself. */ module_put(owner); @@ -1063,7 +1064,7 @@ static struct gendisk *lookup_gendisk(dev_t dev, int *partno) return dev_to_disk(kobj_to_dev(kobj)); goto retry; } - mutex_unlock(&block_class_lock); + mutex_unlock(&bdev_map_lock); return NULL; }