netfs: zero the tail of a short DIO/unbuffered readgrafted

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 <dhowells@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Shyam Prasad N <sprasad@microsoft.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Bharath SM <bharathsm@microsoft.com>
Cc: stable@vger.kernel.org

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/pinctrl/aspeed/Kconfig b/drivers/pinctrl/aspeed/Kconfig
new file mode 100644
index 000000000..8e1d4da08
--- /dev/null
+++ b/drivers/pinctrl/aspeed/Kconfig
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config PINCTRL_ASPEED
+	bool
+	depends on (ARCH_ASPEED || COMPILE_TEST) && OF
+	select MFD_SYSCON
+	select PINMUX
+	select PINCONF
+	select GENERIC_PINCONF
+	select REGMAP_MMIO
+
+config PINCTRL_ASPEED_G4
+	bool "Aspeed G4 SoC pin control"
+	depends on (MACH_ASPEED_G4 || COMPILE_TEST) && OF
+	select PINCTRL_ASPEED
+	help
+	  Say Y here to enable pin controller support for Aspeed's 4th
+	  generation SoCs. GPIO is provided by a separate GPIO driver.
+
+config PINCTRL_ASPEED_G5
+	bool "Aspeed G5 SoC pin control"
+	depends on (MACH_ASPEED_G5 || COMPILE_TEST) && OF
+	select PINCTRL_ASPEED
+	help
+	  Say Y here to enable pin controller support for Aspeed's 5th
+	  generation SoCs. GPIO is provided by a separate GPIO driver.
+
+config PINCTRL_ASPEED_G6
+	bool "Aspeed G6 SoC pin control"
+	depends on (MACH_ASPEED_G6 || COMPILE_TEST) && OF
+	select PINCTRL_ASPEED
+	help
+	  Say Y here to enable pin controller support for Aspeed's 6th
+	  generation SoCs. GPIO is provided by a separate GPIO driver.
+
+config PINCTRL_ASPEED_G7_SOC0
+	bool "Aspeed G7 SoC pin control"
+	depends on (ARCH_ASPEED || COMPILE_TEST) && OF
+	select PINCTRL_ASPEED
+	help
+	  Say Y here to enable pin controller support for the SoC0 instance
+	  of Aspeed's 7th generation SoCs. GPIO is provided by a separate
+	  GPIO driver.
+
+config PINCTRL_ASPEED_G7_SOC1
+	bool "Aspeed G7 SoC1 pin control"
+	depends on (ARCH_ASPEED || COMPILE_TEST) && OF
+	select MFD_SYSCON
+	select PINMUX
+	select GENERIC_PINCTRL_GROUPS
+	select GENERIC_PINMUX_FUNCTIONS
+	select GENERIC_PINCONF
+	select REGMAP_MMIO
+	help
+	  Say Y here to enable pin controller support for the SoC1 instance
+	  of Aspeed's 7th generation SoCs. GPIO is provided by a separate
+	  GPIO driver.