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, 46 insertions, 0 deletions

diff --git a/drivers/accessibility/speakup/DefaultKeyAssignments b/drivers/accessibility/speakup/DefaultKeyAssignments
new file mode 100644
index 000000000..101c803b2
--- /dev/null
+++ b/drivers/accessibility/speakup/DefaultKeyAssignments
@@ -0,0 +1,46 @@
+This file is intended to give you an overview of the default keys used
+by speakup for it's review functions.  You may change them to be
+anything you want but that will take some familiarity with key
+mapping.
+
+We have remapped the insert or zero key on the keypad to act as a
+shift key.  Well, actually as an altgr key.  So in the following list
+InsKeyPad-period means hold down the insert key like a shift key and
+hit the keypad period.
+
+KeyPad-8		Say current Line
+InsKeyPad-8		say from top of screen to reading cursor.
+KeyPad-7		Say Previous Line (UP one line)
+KeyPad-9		Say Next Line (down one line)
+KeyPad-5		Say Current Word
+InsKeyPad-5		Spell Current Word
+KeyPad-4		Say Previous Word (left one word)
+InsKeyPad-4		say from left edge of line to reading cursor.
+KeyPad-6		Say Next Word (right one word)
+InsKeyPad-6		Say from reading cursor to right edge of line.
+KeyPad-2		Say Current Letter
+InsKeyPad-2		say current letter phonetically
+KeyPad-1		Say Previous Character (left one letter)
+KeyPad-3		Say Next Character (right one letter)
+KeyPad-plus		Say Entire Screen
+InsKeyPad-plus		Say from reading cursor line to bottom of screen.
+KeyPad-Minus		Park reading cursor (toggle)
+InsKeyPad-minus		Say character hex and decimal value.
+KeyPad-period		Say Position (current line, position and console)
+InsKeyPad-period	say colour attributes of current position.
+InsKeyPad-9		Move reading cursor to top of screen (insert pgup)
+InsKeyPad-3		Move reading cursor to bottom of screen (insert pgdn)
+InsKeyPad-7		Move reading cursor to left edge of screen (insert home)
+InsKeyPad-1		Move reading cursor to right edge of screen (insert end)
+ControlKeyPad-1		Move reading cursor to last character on current line.
+KeyPad-Enter		Shut Up (until another key is hit) and sync reading cursor
+InsKeyPad-Enter		Shut Up (until toggled back on).
+InsKeyPad-star n<x|y>	go to line (y) or column (x). Where 'n' is any
+		allowed value for the row or column for your current screen.
+KeyPad-/		Mark and Cut screen region.
+InsKeyPad-/		Paste screen region into any console.
+
+Hitting any key while speakup is outputting speech will quiet the
+synth until it has caught up with what is being printed on the
+console.
+