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/usb/chipidea/trace.h | 92 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 drivers/usb/chipidea/trace.h (limited to 'drivers/usb/chipidea/trace.h') diff --git a/drivers/usb/chipidea/trace.h b/drivers/usb/chipidea/trace.h new file mode 100644 index 000000000..1875419cd --- /dev/null +++ b/drivers/usb/chipidea/trace.h @@ -0,0 +1,92 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Trace support header file for device mode + * + * Copyright (C) 2020 NXP + * + * Author: Peter Chen + */ + +#undef TRACE_SYSTEM +#define TRACE_SYSTEM chipidea + +#if !defined(__LINUX_CHIPIDEA_TRACE) || defined(TRACE_HEADER_MULTI_READ) +#define __LINUX_CHIPIDEA_TRACE + +#include +#include +#include +#include "ci.h" +#include "udc.h" + +#define CHIPIDEA_MSG_MAX 500 + +void ci_log(struct ci_hdrc *ci, const char *fmt, ...); + +TRACE_EVENT(ci_log, + TP_PROTO(struct ci_hdrc *ci, struct va_format *vaf), + TP_ARGS(ci, vaf), + TP_STRUCT__entry( + __string(name, dev_name(ci->dev)) + __vstring(msg, vaf->fmt, vaf->va) + ), + TP_fast_assign( + __assign_str(name); + __assign_vstr(msg, vaf->fmt, vaf->va); + ), + TP_printk("%s: %s", __get_str(name), __get_str(msg)) +); + +DECLARE_EVENT_CLASS(ci_log_trb, + TP_PROTO(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq, struct td_node *td), + TP_ARGS(hwep, hwreq, td), + TP_STRUCT__entry( + __string(name, hwep->name) + __field(struct td_node *, td) + __field(struct usb_request *, req) + __field(dma_addr_t, dma) + __field(s32, td_remaining_size) + __field(u32, next) + __field(u32, token) + __field(u32, type) + ), + TP_fast_assign( + __assign_str(name); + __entry->req = &hwreq->req; + __entry->td = td; + __entry->dma = td->dma; + __entry->td_remaining_size = td->td_remaining_size; + __entry->next = le32_to_cpu(td->ptr->next); + __entry->token = le32_to_cpu(td->ptr->token); + __entry->type = usb_endpoint_type(hwep->ep.desc); + ), + TP_printk("%s: req: %p, td: %p, td_dma_address: %pad, remaining_size: %d, " + "next: %x, total bytes: %d, status: %lx", + __get_str(name), __entry->req, __entry->td, &__entry->dma, + __entry->td_remaining_size, __entry->next, + (int)((__entry->token & TD_TOTAL_BYTES) >> __ffs(TD_TOTAL_BYTES)), + __entry->token & TD_STATUS + ) +); + +DEFINE_EVENT(ci_log_trb, ci_prepare_td, + TP_PROTO(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq, struct td_node *td), + TP_ARGS(hwep, hwreq, td) +); + +DEFINE_EVENT(ci_log_trb, ci_complete_td, + TP_PROTO(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq, struct td_node *td), + TP_ARGS(hwep, hwreq, td) +); + +#endif /* __LINUX_CHIPIDEA_TRACE */ + +/* this part must be outside header guard */ + +#undef TRACE_INCLUDE_PATH +#define TRACE_INCLUDE_PATH . + +#undef TRACE_INCLUDE_FILE +#define TRACE_INCLUDE_FILE trace + +#include -- cgit v1.3.1