From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fout-a8-smtp.messagingengine.com (fout-a8-smtp.messagingengine.com [103.168.172.151]) (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 4825140096C; Thu, 16 Jul 2026 10:20:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=103.168.172.151 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784197211; cv=none; b=sMyjCEE3Opb6M1ZAyAgMopSNZpY7Zj6GBkydmOVfFwDfh2rhFdPaPjkEPXxMqd5Tv9ldE5QnpvSeV+yYsNycxOg4f9vC4IrqiNIHLrTwYyeKHaOL4Ruyj59tbeu91B+5N/QDVEHPfctrCGNngFLDHYw4v2ul7o+OHERGHZniMr4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784197211; c=relaxed/simple; bh=W+qxDMK9vjaprSkSPJrXxuBc5SyHoiKsT/9mqwPusPQ=; h=To:Cc:Message-ID:In-Reply-To:References:From:Subject:Date; b=kmMqeRzhQhYcbKsWHAaiw38NzKNb1UqgXR0eCnG9TsDOJLfEvFGAu20ywg+IVsrW1TG1Nlm9dGdFfDspt/uFLAoT+8qwCS7ahKcWUdFvWFAw1kYzYzfhbpJHbl96DRxI3pGj3POPmiqClE1wRbe+45/SvkDaMU2yP5yhvYzS2Es= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org; spf=none smtp.mailfrom=linux-m68k.org; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b=gjMEDOhA; arc=none smtp.client-ip=103.168.172.151 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux-m68k.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="gjMEDOhA" Received: from phl-compute-12.internal (phl-compute-12.internal [10.202.2.52]) by mailfout.phl.internal (Postfix) with ESMTP id 89FA3EC019D; Thu, 16 Jul 2026 06:20:09 -0400 (EDT) Received: from phl-frontend-04 ([10.202.2.163]) by phl-compute-12.internal (MEProxy); Thu, 16 Jul 2026 06:20:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:feedback-id :feedback-id:from:from:in-reply-to:in-reply-to:message-id :references:reply-to:subject:subject:to:to:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm2; t=1784197209; x= 1784283609; bh=KFIl1qcajTm91cZmcEXNfFqEG1xkNZjr1CSuzERE7tY=; b=g jMEDOhA0lG6cAtvCd+PL9XN11Ae6EuKFSPQBXBkodNzGCFlCtA7rizsnCXD8vSN+ SFoODgX5fUj6MNvrsWQwe5D6eF5QX9vB/+A8TiQoZcQdKOsBsR9Axi+WMpTbj+cU JUbfLWK6xaCau41X8VIYrbzwrReV/5VXXlQpV+ZP2Ng2LqMwbuxKEz8WQRYAE2/n HKQVWbEIu4jNublFf/Jb7nN3+0CCQKXlGzUenRyNFc4XG9SIgrM0U1KvgLPWHjDv 7GvoXFv3quszAi5sMvXdwb/O0SZUULRWwyhoOqMisTeUdNSBUz/bJjE/IZn4zRmL PeDUx0REQv9GZX8v+8ilg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: dmFkZTF5Vj6SMnL8eVqPH19rXSXYFY6bmUyIoIPempWpt6RoQSweRYHbiNk5m+J6sOC/Df QLYvSnliCZuWD1s2mWahZuN7gCKrYPBFFnsiZQIW71i1lMh/ZXBxMq0tP9aULtTK+H7/xX Ww9JWg1/lFcZQlPVV6Q5Bq9c9Blcib4cAYDkI8jTrr/ZPXvvNG/6NTq4K5IPCw9N9+gHtb isKzZAEeG45eYU42dcGWZUrYrrIbz2mg+YmDde/CburzcJqnVYm06Mx8ERUN23RPu6Q8Oh GsUURWluJMmbbIpIw7ihDXg/j+GrDcjAYLvJprCSezUF3CQjsj5AjdVlyTm3K3zd9zPEoI +kgkyaFBG1/JbQqckWV+MnZ0e4Rq0NlZ7tFtC+SHOpahN1mhOHvNnAd0khoz4ITsvFAL4H ELNMD3OKUlqDcPaKYH9aTlnhQrxaXfgpyRyNY0BS4td6zhMXrorxcESrimbIYFoMXGF6Is zDjDqlCEFQEAQ6sDNwCk08Gn+wYZx2Agpb0+xY9dttRnE8JqC/S1DEcpInFS+WafS+kFX0 H79UsAefVJN9Ly/onXq8krt67meSvJC+RTeYWBaqFyDfKvbjkbQmdzV15sAjz1Mr7rBJPU hdJEDhYbU1KsArvGfOlZjcgDz7sD9WE7SCVDCHzbP4BzwG/o9YlcHzwv3upA X-ME-Proxy: Feedback-ID: i58a146ae:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 16 Jul 2026 06:20:07 -0400 (EDT) To: Jens Axboe Cc: Laurent Vivier , Geert Uytterhoeven , Joshua Thompson , linux-block@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-kernel@vger.kernel.org, Omar Sandoval Message-ID: <33f99f4aad5a482c5465bcef4d3542cbb2a51dbf.1784196135.git.fthain@linux-m68k.org> In-Reply-To: References: From: Finn Thain Subject: [PATCH 17/31] swim: Convert to blocking queue Date: Thu, 16 Jul 2026 20:02:15 +1000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: These drives are slow: completing a request can take hundreds of milliseconds. Delays are managed by disabling interrupts judiciously and sleeping opportunistically. As of commit e3896d77b702 ("swim: convert to blk-mq"), a spinlock is taken in irq mode as soon as a request is issued. That lock is held for the duration of the request. Hence the driver sleeps while holding the lock which is forbidden. Adopt BLK_MQ_F_BLOCKING and remove the spinlock. Use a mutex to serialize requests from the two request queues. (The chip cannot simultaneously process requests on both internal and external drive.) Cc: Omar Sandoval Fixes: e3896d77b702 ("swim: convert to blk-mq") Signed-off-by: Finn Thain --- drivers/block/swim.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/block/swim.c b/drivers/block/swim.c index e2a8c4ba4e39..6f93ebaaffb7 100644 --- a/drivers/block/swim.c +++ b/drivers/block/swim.c @@ -211,7 +211,6 @@ enum head { struct swim_priv { struct swim __iomem *base; - spinlock_t lock; int floppy_count; struct floppy_state unit[FD_MAX_UNIT]; }; @@ -537,12 +536,10 @@ static blk_status_t swim_queue_rq(struct blk_mq_hw_ctx *hctx, const struct blk_mq_queue_data *bd) { struct floppy_state *fs = hctx->queue->queuedata; - struct swim_priv *swd = fs->swd; struct request *req = bd->rq; blk_status_t err; - if (!spin_trylock_irq(&swd->lock)) - return BLK_STS_DEV_RESOURCE; + mutex_lock(&swim_mutex); blk_mq_start_request(req); @@ -560,7 +557,7 @@ static blk_status_t swim_queue_rq(struct blk_mq_hw_ctx *hctx, err = BLK_STS_OK; out: - spin_unlock_irq(&swd->lock); + mutex_unlock(&swim_mutex); return err; } @@ -839,11 +836,9 @@ static int swim_floppy_init(struct platform_device *pdev) return -EBUSY; } - spin_lock_init(&swd->lock); - for (drive = 0; drive < swd->floppy_count; drive++) { err = blk_mq_alloc_sq_tag_set(&swd->unit[drive].tag_set, - &swim_mq_ops, 2, 0); + &swim_mq_ops, 2, BLK_MQ_F_BLOCKING); if (err) goto exit_put_disks; -- 2.52.0