From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 EB8F4C82563 for ; Mon, 16 Nov 2020 15:01:01 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 698062462E for ; Mon, 16 Nov 2020 15:01:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 698062462E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-481-ei3CaI9FPsyWOGpPL2U88A-1; Mon, 16 Nov 2020 10:00:43 -0500 X-MC-Unique: ei3CaI9FPsyWOGpPL2U88A-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B9B9ED8EE5; Mon, 16 Nov 2020 15:00:16 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 914F75B4A2; Mon, 16 Nov 2020 15:00:16 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 5C23C5812C; Mon, 16 Nov 2020 15:00:16 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 0AGF0AnW015843 for ; Mon, 16 Nov 2020 10:00:10 -0500 Received: by smtp.corp.redhat.com (Postfix) id F059B2023598; Mon, 16 Nov 2020 15:00:09 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast06.extmail.prod.ext.rdu2.redhat.com [10.11.55.22]) by smtp.corp.redhat.com (Postfix) with ESMTPS id EB8912011553 for ; Mon, 16 Nov 2020 15:00:07 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-2.mimecast.com [207.211.31.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 9415B1823603 for ; Mon, 16 Nov 2020 15:00:07 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-257-68n68FIWPSKJIxm8VHi5Jg-1; Mon, 16 Nov 2020 09:59:21 -0500 X-MC-Unique: 68n68FIWPSKJIxm8VHi5Jg-1 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 1kefyO-00040T-NC; Mon, 16 Nov 2020 14:59:17 +0000 From: Christoph Hellwig To: Jens Axboe Date: Mon, 16 Nov 2020 15:57:38 +0100 Message-Id: <20201116145809.410558-48-hch@lst.de> 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 X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Mimecast-Bulk-Signature: yes X-Mimecast-Spam-Signature: bulk X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-loop: dm-devel@redhat.com Cc: Justin Sanders , Mike Snitzer , "Michael S. Tsirkin" , Jason Wang , linux-nvme@lists.infradead.org, Song Liu , dm-devel@redhat.com, linux-scsi@vger.kernel.org, xen-devel@lists.xenproject.org, Ilya Dryomov , Jack Wang , Konrad Rzeszutek Wilk , Josef Bacik , nbd@other.debian.org, linux-raid@vger.kernel.org, Stefan Hajnoczi , drbd-dev@tron.linbit.com, ceph-devel@vger.kernel.org, linux-block@vger.kernel.org, "Martin K. Petersen" , Minchan Kim , linux-fsdevel@vger.kernel.org, Paolo Bonzini , =?UTF-8?q?Roger=20Pau=20Monn=C3=A9?= Subject: [dm-devel] [PATCH 47/78] floppy: use a separate gendisk for each media format X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit The floppy driver usually autodetects the media when used with the normal /dev/fd? devices, which also are the only nodes created by udev. But it also supports various aliases that force a given media format. That is currently supported using the blk_register_region framework which finds the floppy gendisk even for a 'mismatched' dev_t. The problem with this (besides the code complexity) is that it creates multiple struct block_device instances for the whole device of a single gendisk, which can lead to interesting issues in code not aware of that fact. To fix this just create a separate gendisk for each of the aliases if they are accessed. Signed-off-by: Christoph Hellwig --- drivers/block/floppy.c | 154 ++++++++++++++++++++++++++--------------- 1 file changed, 97 insertions(+), 57 deletions(-) diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 7df79ae6b0a1e1..dfe1dfc901ccc2 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -402,7 +402,6 @@ static struct floppy_drive_params drive_params[N_DRIVE]; static struct floppy_drive_struct drive_state[N_DRIVE]; static struct floppy_write_errors write_errors[N_DRIVE]; static struct timer_list motor_off_timer[N_DRIVE]; -static struct gendisk *disks[N_DRIVE]; static struct blk_mq_tag_set tag_sets[N_DRIVE]; static struct block_device *opened_bdev[N_DRIVE]; static DEFINE_MUTEX(open_lock); @@ -477,6 +476,8 @@ static struct floppy_struct floppy_type[32] = { { 3200,20,2,80,0,0x1C,0x00,0xCF,0x2C,"H1600" }, /* 31 1.6MB 3.5" */ }; +static struct gendisk *disks[N_DRIVE][ARRAY_SIZE(floppy_type)]; + #define SECTSIZE (_FD_SECTSIZE(*floppy)) /* Auto-detection: Disk type used until the next media change occurs. */ @@ -4111,7 +4112,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode) new_dev = MINOR(bdev->bd_dev); drive_state[drive].fd_device = new_dev; - set_capacity(disks[drive], floppy_sizes[new_dev]); + set_capacity(disks[drive][ITYPE(new_dev)], floppy_sizes[new_dev]); if (old_dev != -1 && old_dev != new_dev) { if (buffer_drive == drive) buffer_track = -1; @@ -4579,15 +4580,58 @@ static bool floppy_available(int drive) return true; } -static struct kobject *floppy_find(dev_t dev, int *part, void *data) +static int floppy_alloc_disk(unsigned int drive, unsigned int type) { - int drive = (*part & 3) | ((*part & 0x80) >> 5); - if (drive >= N_DRIVE || !floppy_available(drive)) - return NULL; - if (((*part >> 2) & 0x1f) >= ARRAY_SIZE(floppy_type)) - return NULL; - *part = 0; - return get_disk_and_module(disks[drive]); + struct gendisk *disk; + int err; + + disk = alloc_disk(1); + if (!disk) + return -ENOMEM; + + disk->queue = blk_mq_init_queue(&tag_sets[drive]); + if (IS_ERR(disk->queue)) { + err = PTR_ERR(disk->queue); + disk->queue = NULL; + put_disk(disk); + return err; + } + + blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH); + blk_queue_max_hw_sectors(disk->queue, 64); + disk->major = FLOPPY_MAJOR; + disk->first_minor = TOMINOR(drive) | (type << 2); + disk->fops = &floppy_fops; + disk->events = DISK_EVENT_MEDIA_CHANGE; + if (type) + sprintf(disk->disk_name, "fd%d_type%d", drive, type); + else + sprintf(disk->disk_name, "fd%d", drive); + /* to be cleaned up... */ + disk->private_data = (void *)(long)drive; + disk->flags |= GENHD_FL_REMOVABLE; + + disks[drive][type] = disk; + return 0; +} + +static DEFINE_MUTEX(floppy_probe_lock); + +static void floppy_probe(dev_t dev) +{ + unsigned int drive = (MINOR(dev) & 3) | ((MINOR(dev) & 0x80) >> 5); + unsigned int type = (MINOR(dev) >> 2) & 0x1f; + + if (drive >= N_DRIVE || !floppy_available(drive) || + type >= ARRAY_SIZE(floppy_type)) + return; + + mutex_lock(&floppy_probe_lock); + if (!disks[drive][type]) { + if (floppy_alloc_disk(drive, type) == 0) + add_disk(disks[drive][type]); + } + mutex_unlock(&floppy_probe_lock); } static int __init do_floppy_init(void) @@ -4609,33 +4653,25 @@ static int __init do_floppy_init(void) return -ENOMEM; for (drive = 0; drive < N_DRIVE; drive++) { - disks[drive] = alloc_disk(1); - if (!disks[drive]) { - err = -ENOMEM; + memset(&tag_sets[drive], 0, sizeof(tag_sets[drive])); + tag_sets[drive].ops = &floppy_mq_ops; + tag_sets[drive].nr_hw_queues = 1; + tag_sets[drive].nr_maps = 1; + tag_sets[drive].queue_depth = 2; + tag_sets[drive].numa_node = NUMA_NO_NODE; + tag_sets[drive].flags = BLK_MQ_F_SHOULD_MERGE; + err = blk_mq_alloc_tag_set(&tag_sets[drive]); + if (err) goto out_put_disk; - } - disks[drive]->queue = blk_mq_init_sq_queue(&tag_sets[drive], - &floppy_mq_ops, 2, - BLK_MQ_F_SHOULD_MERGE); - if (IS_ERR(disks[drive]->queue)) { - err = PTR_ERR(disks[drive]->queue); - disks[drive]->queue = NULL; + err = floppy_alloc_disk(drive, 0); + if (err) goto out_put_disk; - } - - blk_queue_bounce_limit(disks[drive]->queue, BLK_BOUNCE_HIGH); - blk_queue_max_hw_sectors(disks[drive]->queue, 64); - disks[drive]->major = FLOPPY_MAJOR; - disks[drive]->first_minor = TOMINOR(drive); - disks[drive]->fops = &floppy_fops; - disks[drive]->events = DISK_EVENT_MEDIA_CHANGE; - sprintf(disks[drive]->disk_name, "fd%d", drive); timer_setup(&motor_off_timer[drive], motor_off_callback, 0); } - err = register_blkdev(FLOPPY_MAJOR, "fd"); + err = __register_blkdev(FLOPPY_MAJOR, "fd", floppy_probe); if (err) goto out_put_disk; @@ -4643,9 +4679,6 @@ static int __init do_floppy_init(void) if (err) goto out_unreg_blkdev; - blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE, - floppy_find, NULL, NULL); - for (i = 0; i < 256; i++) if (ITYPE(i)) floppy_sizes[i] = floppy_type[ITYPE(i)].size; @@ -4673,7 +4706,7 @@ static int __init do_floppy_init(void) if (fdc_state[0].address == -1) { cancel_delayed_work(&fd_timeout); err = -ENODEV; - goto out_unreg_region; + goto out_unreg_driver; } #if N_FDC > 1 fdc_state[1].address = FDC2; @@ -4684,7 +4717,7 @@ static int __init do_floppy_init(void) if (err) { cancel_delayed_work(&fd_timeout); err = -EBUSY; - goto out_unreg_region; + goto out_unreg_driver; } /* initialise drive state */ @@ -4761,10 +4794,8 @@ static int __init do_floppy_init(void) if (err) goto out_remove_drives; - /* to be cleaned up... */ - disks[drive]->private_data = (void *)(long)drive; - disks[drive]->flags |= GENHD_FL_REMOVABLE; - device_add_disk(&floppy_device[drive].dev, disks[drive], NULL); + device_add_disk(&floppy_device[drive].dev, disks[drive][0], + NULL); } return 0; @@ -4772,30 +4803,27 @@ static int __init do_floppy_init(void) out_remove_drives: while (drive--) { if (floppy_available(drive)) { - del_gendisk(disks[drive]); + del_gendisk(disks[drive][0]); platform_device_unregister(&floppy_device[drive]); } } out_release_dma: if (atomic_read(&usage_count)) floppy_release_irq_and_dma(); -out_unreg_region: - blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256); +out_unreg_driver: platform_driver_unregister(&floppy_driver); out_unreg_blkdev: unregister_blkdev(FLOPPY_MAJOR, "fd"); out_put_disk: destroy_workqueue(floppy_wq); for (drive = 0; drive < N_DRIVE; drive++) { - if (!disks[drive]) + if (!disks[drive][0]) break; - if (disks[drive]->queue) { - del_timer_sync(&motor_off_timer[drive]); - blk_cleanup_queue(disks[drive]->queue); - disks[drive]->queue = NULL; - blk_mq_free_tag_set(&tag_sets[drive]); - } - put_disk(disks[drive]); + del_timer_sync(&motor_off_timer[drive]); + blk_cleanup_queue(disks[drive][0]->queue); + disks[drive][0]->queue = NULL; + blk_mq_free_tag_set(&tag_sets[drive]); + put_disk(disks[drive][0]); } return err; } @@ -5006,9 +5034,8 @@ module_init(floppy_module_init); static void __exit floppy_module_exit(void) { - int drive; + int drive, i; - blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256); unregister_blkdev(FLOPPY_MAJOR, "fd"); platform_driver_unregister(&floppy_driver); @@ -5018,10 +5045,16 @@ static void __exit floppy_module_exit(void) del_timer_sync(&motor_off_timer[drive]); if (floppy_available(drive)) { - del_gendisk(disks[drive]); + for (i = 0; i < ARRAY_SIZE(floppy_type); i++) { + if (disks[drive][i]) + del_gendisk(disks[drive][i]); + } platform_device_unregister(&floppy_device[drive]); } - blk_cleanup_queue(disks[drive]->queue); + for (i = 0; i < ARRAY_SIZE(floppy_type); i++) { + if (disks[drive][i]) + blk_cleanup_queue(disks[drive][i]->queue); + } blk_mq_free_tag_set(&tag_sets[drive]); /* @@ -5029,10 +5062,17 @@ static void __exit floppy_module_exit(void) * queue reference in put_disk(). */ if (!(allowed_drive_mask & (1 << drive)) || - fdc_state[FDC(drive)].version == FDC_NONE) - disks[drive]->queue = NULL; + fdc_state[FDC(drive)].version == FDC_NONE) { + for (i = 0; i < ARRAY_SIZE(floppy_type); i++) { + if (disks[drive][i]) + disks[drive][i]->queue = NULL; + } + } - put_disk(disks[drive]); + for (i = 0; i < ARRAY_SIZE(floppy_type); i++) { + if (disks[drive][i]) + put_disk(disks[drive][i]); + } } cancel_delayed_work_sync(&fd_timeout); -- 2.29.2 -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel