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 --- include/sound/seq_kernel.h | 102 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) create mode 100644 include/sound/seq_kernel.h (limited to 'include/sound/seq_kernel.h') diff --git a/include/sound/seq_kernel.h b/include/sound/seq_kernel.h new file mode 100644 index 000000000..00c32eed2 --- /dev/null +++ b/include/sound/seq_kernel.h @@ -0,0 +1,102 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef __SOUND_SEQ_KERNEL_H +#define __SOUND_SEQ_KERNEL_H + +/* + * Main kernel header file for the ALSA sequencer + * Copyright (c) 1998 by Frank van de Pol + */ +#include +#include + +typedef struct snd_seq_real_time snd_seq_real_time_t; +typedef union snd_seq_timestamp snd_seq_timestamp_t; + +/* maximum number of queues */ +#define SNDRV_SEQ_MAX_QUEUES 32 + +/* max number of concurrent clients */ +#define SNDRV_SEQ_MAX_CLIENTS 192 + +/* max number of concurrent ports */ +#define SNDRV_SEQ_MAX_PORTS 254 + +/* max number of events in memory pool */ +#define SNDRV_SEQ_MAX_EVENTS 2000 + +/* default number of events in memory pool */ +#define SNDRV_SEQ_DEFAULT_EVENTS 500 + +/* max number of events in memory pool for one client (outqueue) */ +#define SNDRV_SEQ_MAX_CLIENT_EVENTS 2000 + +/* default number of events in memory pool for one client (outqueue) */ +#define SNDRV_SEQ_DEFAULT_CLIENT_EVENTS 200 + +/* max delivery path length */ +/* NOTE: this shouldn't be greater than MAX_LOCKDEP_SUBCLASSES */ +#define SNDRV_SEQ_MAX_HOPS 8 + +/* max size of event size */ +#define SNDRV_SEQ_MAX_EVENT_LEN 0x3fffffff + +/* call-backs for kernel port */ +struct snd_seq_port_callback { + struct module *owner; + void *private_data; + int (*subscribe)(void *private_data, struct snd_seq_port_subscribe *info); + int (*unsubscribe)(void *private_data, struct snd_seq_port_subscribe *info); + int (*use)(void *private_data, struct snd_seq_port_subscribe *info); + int (*unuse)(void *private_data, struct snd_seq_port_subscribe *info); + int (*event_input)(struct snd_seq_event *ev, int direct, void *private_data, int atomic, int hop); + void (*private_free)(void *private_data); + /*...*/ +}; + +/* interface for kernel client */ +__printf(3, 4) +int snd_seq_create_kernel_client(struct snd_card *card, int client_index, + const char *name_fmt, ...); +int snd_seq_delete_kernel_client(int client); +int snd_seq_kernel_client_enqueue(int client, struct snd_seq_event *ev, + struct file *file, bool blocking); +int snd_seq_kernel_client_dispatch(int client, struct snd_seq_event *ev, int atomic, int hop); +int snd_seq_kernel_client_ctl(int client, unsigned int cmd, void *arg); + +#define SNDRV_SEQ_EXT_MASK 0xc0000000 +#define SNDRV_SEQ_EXT_USRPTR 0x80000000 +#define SNDRV_SEQ_EXT_CHAINED 0x40000000 + +typedef int (*snd_seq_dump_func_t)(void *ptr, void *buf, int count); +int snd_seq_expand_var_event(const struct snd_seq_event *event, int count, char *buf, + int in_kernel, int size_aligned); +int snd_seq_expand_var_event_at(const struct snd_seq_event *event, int count, + char *buf, int offset); +int snd_seq_dump_var_event(const struct snd_seq_event *event, + snd_seq_dump_func_t func, void *private_data); + +/* size of the event packet; it can be greater than snd_seq_event size */ +static inline size_t snd_seq_event_packet_size(struct snd_seq_event *ev) +{ + if (snd_seq_ev_is_ump(ev)) + return sizeof(struct snd_seq_ump_event); + return sizeof(struct snd_seq_event); +} + +/* interface for OSS emulation */ +int snd_seq_set_queue_tempo(int client, struct snd_seq_queue_tempo *tempo); + +/* port attach/detach */ +int snd_seq_event_port_attach(int client, struct snd_seq_port_callback *pcbp, + int cap, int type, int midi_channels, int midi_voices, char *portname); +int snd_seq_event_port_detach(int client, int port); + +#ifdef CONFIG_MODULES +void snd_seq_autoload_init(void); +void snd_seq_autoload_exit(void); +#else +#define snd_seq_autoload_init() +#define snd_seq_autoload_exit() +#endif + +#endif /* __SOUND_SEQ_KERNEL_H */ -- cgit v1.3.1