The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x c1976bd8f23016d8706973908f2bb0ac0d852a8f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023040358-blade-preheated-5a2d@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..

Possible dependencies:

c1976bd8f230 ("zonefs: Always invalidate last cached page on append write") 4008e2a0b01a ("zonefs: Reorganize code") a608da3bd730 ("zonefs: Detect append writes at invalid locations") 8745889a7fd0 ("Merge tag 'iomap-6.0-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From c1976bd8f23016d8706973908f2bb0ac0d852a8f Mon Sep 17 00:00:00 2001 From: Damien Le Moal damien.lemoal@opensource.wdc.com Date: Wed, 29 Mar 2023 13:16:01 +0900 Subject: [PATCH] zonefs: Always invalidate last cached page on append write

When a direct append write is executed, the append offset may correspond to the last page of a sequential file inode which might have been cached already by buffered reads, page faults with mmap-read or non-direct readahead. To ensure that the on-disk and cached data is consistant for such last cached page, make sure to always invalidate it in zonefs_file_dio_append(). If the invalidation fails, return -EBUSY to userspace to differentiate from IO errors.

This invalidation will always be a no-op when the FS block size (device zone write granularity) is equal to the page size (e.g. 4K).

Reported-by: Hans Holmberg Hans.Holmberg@wdc.com Fixes: 02ef12a663c7 ("zonefs: use REQ_OP_ZONE_APPEND for sync DIO") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal damien.lemoal@opensource.wdc.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Johannes Thumshirn johannes.thumshirn@wdc.com Tested-by: Hans Holmberg hans.holmberg@wdc.com

diff --git a/fs/zonefs/file.c b/fs/zonefs/file.c index 617e4f9db42e..c6ab2732955e 100644 --- a/fs/zonefs/file.c +++ b/fs/zonefs/file.c @@ -382,6 +382,7 @@ static ssize_t zonefs_file_dio_append(struct kiocb *iocb, struct iov_iter *from) struct zonefs_zone *z = zonefs_inode_zone(inode); struct block_device *bdev = inode->i_sb->s_bdev; unsigned int max = bdev_max_zone_append_sectors(bdev); + pgoff_t start, end; struct bio *bio; ssize_t size = 0; int nr_pages; @@ -390,6 +391,19 @@ static ssize_t zonefs_file_dio_append(struct kiocb *iocb, struct iov_iter *from) max = ALIGN_DOWN(max << SECTOR_SHIFT, inode->i_sb->s_blocksize); iov_iter_truncate(from, max);

+ /* + * If the inode block size (zone write granularity) is smaller than the + * page size, we may be appending data belonging to the last page of the + * inode straddling inode->i_size, with that page already cached due to + * a buffered read or readahead. So make sure to invalidate that page. + * This will always be a no-op for the case where the block size is + * equal to the page size. + */ + start = iocb->ki_pos >> PAGE_SHIFT; + end = (iocb->ki_pos + iov_iter_count(from) - 1) >> PAGE_SHIFT; + if (invalidate_inode_pages2_range(inode->i_mapping, start, end)) + return -EBUSY; + nr_pages = iov_iter_npages(from, BIO_MAX_VECS); if (!nr_pages) return 0;