This is a note to let you know that I've just added the patch titled NFS: Allow very small rsize & wsize again to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nfs-allow-very-small-rsize-wsize-again.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 56d691b7a6635ad7d3a8173c93a8d6eb4891e339 Author: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> Date: Wed Nov 30 15:30:47 2022 -0500 NFS: Allow very small rsize & wsize again [ Upstream commit a60214c2465493aac0b014d87ee19327b6204c42 ] 940261a19508 introduced nfs_io_size() to clamp the iosize to a multiple of PAGE_SIZE. This had the unintended side effect of no longer allowing iosizes less than a page, which could be useful in some situations. UDP already has an exception that causes it to fall back on the power-of-two style sizes instead. This patch adds an additional exception for very small iosizes. Reported-by: Jeff Layton <jlayton@xxxxxxxxxx> Fixes: 940261a19508 ("NFS: Allow setting rsize / wsize to a multiple of PAGE_SIZE") Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index 647fc3f547cb..ae7d4a8c728c 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -739,12 +739,10 @@ unsigned long nfs_io_size(unsigned long iosize, enum xprt_transports proto) iosize = NFS_DEF_FILE_IO_SIZE; else if (iosize >= NFS_MAX_FILE_IO_SIZE) iosize = NFS_MAX_FILE_IO_SIZE; - else - iosize = iosize & PAGE_MASK; - if (proto == XPRT_TRANSPORT_UDP) + if (proto == XPRT_TRANSPORT_UDP || iosize < PAGE_SIZE) return nfs_block_bits(iosize, NULL); - return iosize; + return iosize & PAGE_MASK; } /*