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/gpu/host1x/channel.h | 45 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 drivers/gpu/host1x/channel.h (limited to 'drivers/gpu/host1x/channel.h') diff --git a/drivers/gpu/host1x/channel.h b/drivers/gpu/host1x/channel.h new file mode 100644 index 000000000..d7aede204 --- /dev/null +++ b/drivers/gpu/host1x/channel.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Tegra host1x Channel + * + * Copyright (c) 2010-2013, NVIDIA Corporation. + */ + +#ifndef __HOST1X_CHANNEL_H +#define __HOST1X_CHANNEL_H + +#include +#include +#include + +#include "cdma.h" + +struct host1x; +struct host1x_channel; + +struct host1x_channel_list { + struct host1x_channel *channels; + + struct mutex lock; + unsigned long *allocated_channels; +}; + +struct host1x_channel { + struct kref refcount; + unsigned int id; + struct mutex submitlock; + void __iomem *regs; + struct host1x_client *client; + struct device *dev; + struct host1x_cdma cdma; +}; + +/* channel list operations */ +int host1x_channel_list_init(struct host1x_channel_list *chlist, + unsigned int num_channels); +void host1x_channel_list_free(struct host1x_channel_list *chlist); +struct host1x_channel *host1x_channel_get_index(struct host1x *host, + unsigned int index); +void host1x_channel_stop_all(struct host1x *host); + +#endif -- cgit v1.3.1