From 67871ada3a53895df959305b0bba84a91081a90e Mon Sep 17 00:00:00 2001 From: Denis Efremov Date: Sat, 7 Aug 2021 10:37:02 +0300 Subject: [PATCH] Revert "floppy: reintroduce O_NDELAY fix" commit c7e9d0020361f4308a70cdfd6d5335e273eb8717 upstream. The patch breaks userspace implementations (e.g. fdutils) and introduces regressions in behaviour. Previously, it was possible to O_NDELAY open a floppy device with no media inserted or with write protected media without an error. Some userspace tools use this particular behavior for probing. It's not the first time when we revert this patch. Previous revert is in commit f2791e7eadf4 (Revert "floppy: refactor open() flags handling"). This reverts commit 8a0c014cd20516ade9654fc13b51345ec58e7be8. Link: https://lore.kernel.org/linux-block/de10cb47-34d1-5a88-7751-225ca380f735@compro.net/ Reported-by: Mark Hounschell Cc: Jiri Kosina Cc: Wim Osterholt Cc: Kurt Garloff Cc: Signed-off-by: Denis Efremov Signed-off-by: Greg Kroah-Hartman --- drivers/block/floppy.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 40ea1a425c43..ac97a1e2e5dd 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -4063,22 +4063,21 @@ static int floppy_open(struct block_device *bdev, fmode_t mode) if (UFDCS->rawcmd == 1) UFDCS->rawcmd = 2; - if (mode & (FMODE_READ|FMODE_WRITE)) { - UDRS->last_checked = 0; - clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags); - check_disk_change(bdev); - if (test_bit(FD_DISK_CHANGED_BIT, &UDRS->flags)) - goto out; - if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags)) + if (!(mode & FMODE_NDELAY)) { + if (mode & (FMODE_READ|FMODE_WRITE)) { + UDRS->last_checked = 0; + clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags); + check_disk_change(bdev); + if (test_bit(FD_DISK_CHANGED_BIT, &UDRS->flags)) + goto out; + if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags)) + goto out; + } + res = -EROFS; + if ((mode & FMODE_WRITE) && + !test_bit(FD_DISK_WRITABLE_BIT, &UDRS->flags)) goto out; } - - res = -EROFS; - - if ((mode & FMODE_WRITE) && - !test_bit(FD_DISK_WRITABLE_BIT, &UDRS->flags)) - goto out; - mutex_unlock(&open_lock); mutex_unlock(&floppy_mutex); return 0;