From patchwork Wed Nov 18 08:47:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11914595 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 97A131668 for ; Wed, 18 Nov 2020 09:00:11 +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 307A0221E9 for ; Wed, 18 Nov 2020 09:00:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="TqocbXzD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 307A0221E9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.29536.59051 (Exim 4.92) (envelope-from ) id 1kfJJc-0001TW-E7; Wed, 18 Nov 2020 08:59:48 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 29536.59051; Wed, 18 Nov 2020 08:59:48 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kfJJc-0001TM-A3; Wed, 18 Nov 2020 08:59:48 +0000 Received: by outflank-mailman (input) for mailman id 29536; Wed, 18 Nov 2020 08:59:47 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kfJA0-0006e0-56 for xen-devel@lists.xenproject.org; Wed, 18 Nov 2020 08:49:52 +0000 Received: from casper.infradead.org (unknown [2001:8b0:10b:1236::1]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id f832a971-d419-49f9-bbc7-b121ac062b86; Wed, 18 Nov 2020 08:48:44 +0000 (UTC) Received: from [2001:4bb8:18c:31ba:32b1:ec66:5459:36a] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kfJ8j-0007p0-Ax; Wed, 18 Nov 2020 08:48:33 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kfJA0-0006e0-56 for xen-devel@lists.xenproject.org; Wed, 18 Nov 2020 08:49:52 +0000 X-Inumbo-ID: f832a971-d419-49f9-bbc7-b121ac062b86 Received: from casper.infradead.org (unknown [2001:8b0:10b:1236::1]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id f832a971-d419-49f9-bbc7-b121ac062b86; Wed, 18 Nov 2020 08:48:44 +0000 (UTC) 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=hNtZTYwDbpxOWnjbdPfEN2LKFTEyc+Xwk1zoPtNIsws=; b=TqocbXzDnpX4MzcZ8sgwLOlbAf xsj4dZC9XsQv1XS+z2XyddLzInqJ0/IKShK3LPDT7Eo8ZIpILYJY0gj9VfwBQ3nMuSg/HN+J3xlST FSG10B3yULkQmmKPPGNECUNZ7iTNJ5QD9Ed3/P5kQbf5pUKNe93db9DVG3tkbxyeraQrS6VjfZR1E w5El/hZ6ELQvxKpwQr9399o0aiwHBe3HK6K+ZrCT+dby6bdt46qtWjz7jJb2z7KRzu3kN4k6f+J35 BMhTlxFabVq0KWEkdz8my9MdfYfF/m0hoir4VCd42ijZNbevVJzVu/cbBaaFuWLhgF/M0/GI2ryHL ICIiDKNg==; Received: from [2001:4bb8:18c:31ba:32b1:ec66:5459:36a] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kfJ8j-0007p0-Ax; Wed, 18 Nov 2020 08:48:33 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Tejun Heo , Josef Bacik , Konrad Rzeszutek Wilk , Coly Li , Mike Snitzer , dm-devel@redhat.com, Richard Weinberger , Jan Kara , linux-block@vger.kernel.org, xen-devel@lists.xenproject.org, linux-bcache@vger.kernel.org, linux-mtd@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 18/20] fs: remove get_super_thawed and get_super_exclusive_thawed Date: Wed, 18 Nov 2020 09:47:58 +0100 Message-Id: <20201118084800.2339180-19-hch@lst.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201118084800.2339180-1-hch@lst.de> References: <20201118084800.2339180-1-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 Just open code the wait in the only caller of both functions. Signed-off-by: Christoph Hellwig --- fs/internal.h | 2 ++ fs/quota/quota.c | 31 +++++++++++++++++++++------- fs/super.c | 51 ++-------------------------------------------- include/linux/fs.h | 4 +--- 4 files changed, 29 insertions(+), 59 deletions(-) diff --git a/fs/internal.h b/fs/internal.h index a7cd0f64faa4ab..47be21dfeebef5 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -114,7 +114,9 @@ extern struct file *alloc_empty_file_noaccount(int, const struct cred *); */ extern int reconfigure_super(struct fs_context *); extern bool trylock_super(struct super_block *sb); +struct super_block *__get_super(struct block_device *bdev, bool excl); extern struct super_block *user_get_super(dev_t); +void put_super(struct super_block *sb); extern bool mount_capable(struct fs_context *); /* diff --git a/fs/quota/quota.c b/fs/quota/quota.c index 9af95c7a0bbe3c..f3d32b0d9008f2 100644 --- a/fs/quota/quota.c +++ b/fs/quota/quota.c @@ -20,6 +20,7 @@ #include #include #include "compat.h" +#include "../internal.h" static int check_quotactl_permission(struct super_block *sb, int type, int cmd, qid_t id) @@ -868,6 +869,7 @@ static struct super_block *quotactl_block(const char __user *special, int cmd) struct block_device *bdev; struct super_block *sb; struct filename *tmp = getname(special); + bool excl = false, thawed = false; if (IS_ERR(tmp)) return ERR_CAST(tmp); @@ -875,17 +877,32 @@ static struct super_block *quotactl_block(const char __user *special, int cmd) putname(tmp); if (IS_ERR(bdev)) return ERR_CAST(bdev); - if (quotactl_cmd_onoff(cmd)) - sb = get_super_exclusive_thawed(bdev); - else if (quotactl_cmd_write(cmd)) - sb = get_super_thawed(bdev); - else - sb = get_super(bdev); + + if (quotactl_cmd_onoff(cmd)) { + excl = true; + thawed = true; + } else if (quotactl_cmd_write(cmd)) { + thawed = true; + } + +retry: + sb = __get_super(bdev, excl); + if (thawed && sb && sb->s_writers.frozen != SB_UNFROZEN) { + if (excl) + up_write(&sb->s_umount); + else + up_read(&sb->s_umount); + wait_event(sb->s_writers.wait_unfrozen, + sb->s_writers.frozen == SB_UNFROZEN); + put_super(sb); + goto retry; + } + bdput(bdev); if (!sb) return ERR_PTR(-ENODEV); - return sb; + #else return ERR_PTR(-ENODEV); #endif diff --git a/fs/super.c b/fs/super.c index 98bb0629ee108e..343e5c1e538d2a 100644 --- a/fs/super.c +++ b/fs/super.c @@ -307,7 +307,7 @@ static void __put_super(struct super_block *s) * Drops a temporary reference, frees superblock if there's no * references left. */ -static void put_super(struct super_block *sb) +void put_super(struct super_block *sb) { spin_lock(&sb_lock); __put_super(sb); @@ -740,7 +740,7 @@ void iterate_supers_type(struct file_system_type *type, EXPORT_SYMBOL(iterate_supers_type); -static struct super_block *__get_super(struct block_device *bdev, bool excl) +struct super_block *__get_super(struct block_device *bdev, bool excl) { struct super_block *sb; @@ -789,53 +789,6 @@ struct super_block *get_super(struct block_device *bdev) } EXPORT_SYMBOL(get_super); -static struct super_block *__get_super_thawed(struct block_device *bdev, - bool excl) -{ - while (1) { - struct super_block *s = __get_super(bdev, excl); - if (!s || s->s_writers.frozen == SB_UNFROZEN) - return s; - if (!excl) - up_read(&s->s_umount); - else - up_write(&s->s_umount); - wait_event(s->s_writers.wait_unfrozen, - s->s_writers.frozen == SB_UNFROZEN); - put_super(s); - } -} - -/** - * get_super_thawed - get thawed superblock of a device - * @bdev: device to get the superblock for - * - * Scans the superblock list and finds the superblock of the file system - * mounted on the device. The superblock is returned once it is thawed - * (or immediately if it was not frozen). %NULL is returned if no match - * is found. - */ -struct super_block *get_super_thawed(struct block_device *bdev) -{ - return __get_super_thawed(bdev, false); -} -EXPORT_SYMBOL(get_super_thawed); - -/** - * get_super_exclusive_thawed - get thawed superblock of a device - * @bdev: device to get the superblock for - * - * Scans the superblock list and finds the superblock of the file system - * mounted on the device. The superblock is returned once it is thawed - * (or immediately if it was not frozen) and s_umount semaphore is held - * in exclusive mode. %NULL is returned if no match is found. - */ -struct super_block *get_super_exclusive_thawed(struct block_device *bdev) -{ - return __get_super_thawed(bdev, true); -} -EXPORT_SYMBOL(get_super_exclusive_thawed); - /** * get_active_super - get an active reference to the superblock of a device * @bdev: device to get the superblock for diff --git a/include/linux/fs.h b/include/linux/fs.h index 8667d0cdc71e76..a61df0dd4f1989 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1409,7 +1409,7 @@ enum { struct sb_writers { int frozen; /* Is sb frozen? */ - wait_queue_head_t wait_unfrozen; /* for get_super_thawed() */ + wait_queue_head_t wait_unfrozen; /* wait for thaw */ struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS]; }; @@ -3132,8 +3132,6 @@ extern struct file_system_type *get_filesystem(struct file_system_type *fs); extern void put_filesystem(struct file_system_type *fs); extern struct file_system_type *get_fs_type(const char *name); extern struct super_block *get_super(struct block_device *); -extern struct super_block *get_super_thawed(struct block_device *); -extern struct super_block *get_super_exclusive_thawed(struct block_device *bdev); extern struct super_block *get_active_super(struct block_device *bdev); extern void drop_super(struct super_block *sb); extern void drop_super_exclusive(struct super_block *sb);