From dd05add7b2b6004c5fa3a1f276f56d8668f86b65 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Sat, 26 Sep 2026 19:20:30 -0300 Subject: netfs: zero the tail of a short DIO/unbuffered read The buffered read collector zero-fills the tail of a short read that stops below the inode's i_size (netfs_clear_unread()), so a read that races an extending write still returns the expected number of bytes. The non-buffered collector path does no such thing: it just records how much was transferred. Add the same zero-fill for the non-buffered case, gated on NETFS_SREQ_CLEAR_TAIL: a subreq's source sets that flag when a short result from it is known to be safe to treat as a hole, as opposed to NETFS_SREQ_HIT_EOF, which means the read genuinely ran off the end of the file and should be reported short as-is. Only CLEAR_TAIL should zero-fill here; a real EOF must stay a real short read. No source currently sets CLEAR_TAIL on an unbuffered/DIO subrequest, so this is inert on its own -- a following change teaches cifs to set it in the one case that needs it. Fixes: e2d46f2ec332 ("netfs: Change the read result collector to only use one work item") Reviewed-by: David Howells Reviewed-by: Namjae Jeon Signed-off-by: Paulo Alcantara Cc: Christian Brauner Cc: Matthew Wilcox Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: Bharath SM Cc: stable@vger.kernel.org --- fs/cachefiles/Makefile | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) create mode 100644 fs/cachefiles/Makefile (limited to 'fs/cachefiles/Makefile') diff --git a/fs/cachefiles/Makefile b/fs/cachefiles/Makefile new file mode 100644 index 000000000..16d811f1a --- /dev/null +++ b/fs/cachefiles/Makefile @@ -0,0 +1,20 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for caching in a mounted filesystem +# + +cachefiles-y := \ + cache.o \ + daemon.o \ + interface.o \ + io.o \ + key.o \ + main.o \ + namei.o \ + security.o \ + volume.o \ + xattr.o + +cachefiles-$(CONFIG_CACHEFILES_ERROR_INJECTION) += error_inject.o + +obj-$(CONFIG_CACHEFILES) := cachefiles.o -- cgit v1.3.1