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 --- Documentation/driver-api/target.rst | 52 +++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 Documentation/driver-api/target.rst (limited to 'Documentation/driver-api/target.rst') diff --git a/Documentation/driver-api/target.rst b/Documentation/driver-api/target.rst new file mode 100644 index 000000000..c70ca2517 --- /dev/null +++ b/Documentation/driver-api/target.rst @@ -0,0 +1,52 @@ +================================= +target and iSCSI Interfaces Guide +================================= + +Introduction and Overview +========================= + +TBD + +Target core device interfaces +============================= + +This section is blank because no kerneldoc comments have been added to +drivers/target/target_core_device.c. + +Target core transport interfaces +================================ + +.. kernel-doc:: drivers/target/target_core_transport.c + :export: + +Target-supported userspace I/O +============================== + +.. kernel-doc:: drivers/target/target_core_user.c + :doc: Userspace I/O + +.. kernel-doc:: include/uapi/linux/target_core_user.h + :doc: Ring Design + +iSCSI helper functions +====================== + +.. kernel-doc:: drivers/scsi/libiscsi.c + :export: + + +iSCSI boot information +====================== + +.. kernel-doc:: drivers/scsi/iscsi_boot_sysfs.c + :export: + +iSCSI TCP interfaces +==================== + +.. kernel-doc:: drivers/scsi/iscsi_tcp.c + :internal: + +.. kernel-doc:: drivers/scsi/libiscsi_tcp.c + :export: + -- cgit v1.3.1