From 9f65c489b68d42427dc0651488dd260d678f525d Mon Sep 17 00:00:00 2001 From: Matteo Croce Date: Tue, 13 Jul 2021 01:05:30 +0200 Subject: [PATCH] loop: raise media_change event Make the loop device raise a DISK_MEDIA_CHANGE event on attach or detach. # udevadm monitor -up |grep -e DISK_MEDIA_CHANGE -e DEVNAME & # losetup -f zero [ 7.454235] loop0: detected capacity change from 0 to 16384 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop0 DEVNAME=/dev/loop0 DEVNAME=/dev/loop0 # losetup -f zero [ 10.205245] loop1: detected capacity change from 0 to 16384 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop1 # losetup -f zero2 [ 13.532368] loop2: detected capacity change from 0 to 40960 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop2 DEVNAME=/dev/loop2 # losetup -D DEVNAME=/dev/loop1 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop2 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop2 DEVNAME=/dev/loop0 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop0 Signed-off-by: Matteo Croce Reviewed-by: Christoph Hellwig Tested-by: Luca Boccassi Link: https://lore.kernel.org/r/20210712230530.29323-7-mcroce@linux.microsoft.com Signed-off-by: Jens Axboe --- drivers/block/loop.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index a03ef5025f27..f8486d9b75a4 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -774,6 +774,7 @@ static int loop_change_fd(struct loop_device *lo, struct block_device *bdev, goto out_err; /* and ... switch */ + disk_force_media_change(lo->lo_disk, DISK_EVENT_MEDIA_CHANGE); blk_mq_freeze_queue(lo->lo_queue); mapping_set_gfp_mask(old_file->f_mapping, lo->old_gfp_mask); lo->lo_backing_file = file; @@ -1257,6 +1258,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode, goto out_unlock; } + disk_force_media_change(lo->lo_disk, DISK_EVENT_MEDIA_CHANGE); set_disk_ro(lo->lo_disk, (lo->lo_flags & LO_FLAGS_READ_ONLY) != 0); INIT_WORK(&lo->rootcg_work, loop_rootcg_workfn); @@ -1410,6 +1412,7 @@ static int __loop_clr_fd(struct loop_device *lo, bool release) partscan = lo->lo_flags & LO_FLAGS_PARTSCAN && bdev; lo_number = lo->lo_number; + disk_force_media_change(lo->lo_disk, DISK_EVENT_MEDIA_CHANGE); out_unlock: mutex_unlock(&lo->lo_mutex); if (partscan) { @@ -2386,6 +2389,8 @@ static int loop_add(int i) disk->fops = &lo_fops; disk->private_data = lo; disk->queue = lo->lo_queue; + disk->events = DISK_EVENT_MEDIA_CHANGE; + disk->event_flags = DISK_EVENT_FLAG_UEVENT; sprintf(disk->disk_name, "loop%d", i); add_disk(disk); mutex_unlock(&loop_ctl_mutex); -- 2.20.1