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 --- drivers/accessibility/speakup/thread.c | 62 ++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 drivers/accessibility/speakup/thread.c (limited to 'drivers/accessibility/speakup/thread.c') diff --git a/drivers/accessibility/speakup/thread.c b/drivers/accessibility/speakup/thread.c new file mode 100644 index 000000000..2fc75e60f --- /dev/null +++ b/drivers/accessibility/speakup/thread.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include + +#include "spk_types.h" +#include "speakup.h" +#include "spk_priv.h" + +DECLARE_WAIT_QUEUE_HEAD(speakup_event); +EXPORT_SYMBOL_GPL(speakup_event); + +int speakup_thread(void *data) +{ + unsigned long flags; + int should_break; + struct bleep our_sound; + + our_sound.active = 0; + our_sound.freq = 0; + our_sound.jiffies = 0; + + mutex_lock(&spk_mutex); + while (1) { + DEFINE_WAIT(wait); + + while (1) { + spin_lock_irqsave(&speakup_info.spinlock, flags); + our_sound = spk_unprocessed_sound; + spk_unprocessed_sound.active = 0; + prepare_to_wait(&speakup_event, &wait, + TASK_INTERRUPTIBLE); + should_break = kthread_should_stop() || + our_sound.active || + (synth && synth->catch_up && synth->alive && + (speakup_info.flushing || + !synth_buffer_empty())); + spin_unlock_irqrestore(&speakup_info.spinlock, flags); + if (should_break) + break; + mutex_unlock(&spk_mutex); + schedule(); + mutex_lock(&spk_mutex); + } + finish_wait(&speakup_event, &wait); + if (kthread_should_stop()) + break; + + if (our_sound.active) + kd_mksound(our_sound.freq, our_sound.jiffies); + if (synth && synth->catch_up && synth->alive) { + /* + * It is up to the callee to take the lock, so that it + * can sleep whenever it likes + */ + synth->catch_up(synth); + } + + speakup_start_ttys(); + } + mutex_unlock(&spk_mutex); + return 0; +} -- cgit v1.3.1