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 --- .../admin-guide/media/raspberrypi-pisp-be.dot | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) create mode 100644 Documentation/admin-guide/media/raspberrypi-pisp-be.dot (limited to 'Documentation/admin-guide/media/raspberrypi-pisp-be.dot') diff --git a/Documentation/admin-guide/media/raspberrypi-pisp-be.dot b/Documentation/admin-guide/media/raspberrypi-pisp-be.dot new file mode 100644 index 000000000..55671dc1d --- /dev/null +++ b/Documentation/admin-guide/media/raspberrypi-pisp-be.dot @@ -0,0 +1,20 @@ +digraph board { + rankdir=TB + n00000001 [label="{{ 0 | 1 | 2 | 7} | pispbe\n | { 3 | 4 | 5 | 6}}", shape=Mrecord, style=filled, fillcolor=green] + n00000001:port3 -> n0000001c [style=bold] + n00000001:port4 -> n00000022 [style=bold] + n00000001:port5 -> n00000028 [style=bold] + n00000001:port6 -> n0000002e [style=bold] + n0000000a [label="pispbe-input\n/dev/video0", shape=box, style=filled, fillcolor=yellow] + n0000000a -> n00000001:port0 [style=bold] + n00000010 [label="pispbe-tdn_input\n/dev/video1", shape=box, style=filled, fillcolor=yellow] + n00000010 -> n00000001:port1 [style=bold] + n00000016 [label="pispbe-stitch_input\n/dev/video2", shape=box, style=filled, fillcolor=yellow] + n00000016 -> n00000001:port2 [style=bold] + n0000001c [label="pispbe-output0\n/dev/video3", shape=box, style=filled, fillcolor=yellow] + n00000022 [label="pispbe-output1\n/dev/video4", shape=box, style=filled, fillcolor=yellow] + n00000028 [label="pispbe-tdn_output\n/dev/video5", shape=box, style=filled, fillcolor=yellow] + n0000002e [label="pispbe-stitch_output\n/dev/video6", shape=box, style=filled, fillcolor=yellow] + n00000034 [label="pispbe-config\n/dev/video7", shape=box, style=filled, fillcolor=yellow] + n00000034 -> n00000001:port7 [style=bold] +} -- cgit v1.3.1