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, 32 insertions, 0 deletions

diff --git a/drivers/crypto/caam/Makefile b/drivers/crypto/caam/Makefile
new file mode 100644
index 000000000..a17e3cf14
--- /dev/null
+++ b/drivers/crypto/caam/Makefile
@@ -0,0 +1,32 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the CAAM backend and dependent components
+#
+ifeq ($(CONFIG_CRYPTO_DEV_FSL_CAAM_DEBUG), y)
+	ccflags-y := -DDEBUG
+endif
+
+ccflags-y += -DVERSION=\"\"
+
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_COMMON) += error.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM) += caam.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_JR) += caam_jr.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_DESC) += caamalg_desc.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_AHASH_API_DESC) += caamhash_desc.o
+
+caam-y := ctrl.o
+caam_jr-y := jr.o key_gen.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API) += caamalg.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI) += caamalg_qi.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_AHASH_API) += caamhash.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_API) += caamrng.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_PKC_API) += caampkc.o pkc_desc.o
+caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_BLOB_GEN) += blob_gen.o
+
+caam-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI) += qi.o
+caam-$(CONFIG_DEBUG_FS) += debugfs.o
+
+obj-$(CONFIG_CRYPTO_DEV_FSL_DPAA2_CAAM) += dpaa2_caam.o
+
+dpaa2_caam-y    := caamalg_qi2.o dpseci.o
+dpaa2_caam-$(CONFIG_DEBUG_FS) += dpseci-debugfs.o