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 --- drivers/siox/Kconfig | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 drivers/siox/Kconfig (limited to 'drivers/siox/Kconfig') diff --git a/drivers/siox/Kconfig b/drivers/siox/Kconfig new file mode 100644 index 000000000..4326db32c --- /dev/null +++ b/drivers/siox/Kconfig @@ -0,0 +1,19 @@ +# SPDX-License-Identifier: GPL-2.0-only +menuconfig SIOX + tristate "Eckelmann SIOX Support" + help + SIOX stands for Serial Input Output eXtension and is a synchronous + bus system invented by Eckelmann AG. It is used in their control and + remote monitoring systems for commercial and industrial refrigeration + to drive additional I/O units. + + Unless you know better, it is probably safe to say "no" here. + +if SIOX + +config SIOX_BUS_GPIO + tristate "SIOX GPIO bus driver" + help + SIOX bus driver that controls the four bus lines using GPIOs. + +endif -- cgit v1.3.1