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/mcb/Kconfig | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 drivers/mcb/Kconfig (limited to 'drivers/mcb/Kconfig') diff --git a/drivers/mcb/Kconfig b/drivers/mcb/Kconfig new file mode 100644 index 000000000..0a883486f --- /dev/null +++ b/drivers/mcb/Kconfig @@ -0,0 +1,41 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# MEN Chameleon Bus (MCB) support +# + +menuconfig MCB + tristate "MCB support" + default n + depends on HAS_IOMEM + help + + The MCB (MEN Chameleon Bus) is a Bus specific to MEN Mikroelektronik + FPGA based devices. It is used to identify MCB based IP-Cores within + an FPGA and provide the necessary framework for instantiating drivers + for these devices. + + If build as a module, the module is called mcb.ko + +if MCB +config MCB_PCI + tristate "PCI based MCB carrier" + default n + depends on PCI + help + + This is a MCB carrier on a PCI device. Both PCI attached on-board + FPGAs as well as CompactPCI attached MCB FPGAs are supported with + this driver. + + If build as a module, the module is called mcb-pci.ko + +config MCB_LPC + tristate "LPC (non PCI) based MCB carrier" + default n + help + + This is a MCB carrier on a LPC or non PCI device. + + If build as a module, the module is called mcb-lpc.ko + +endif # MCB -- cgit v1.3.1