From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- sound/firewire/cmp.h | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 sound/firewire/cmp.h (limited to 'sound/firewire/cmp.h') diff --git a/sound/firewire/cmp.h b/sound/firewire/cmp.h new file mode 100644 index 000000000..66fc08b74 --- /dev/null +++ b/sound/firewire/cmp.h @@ -0,0 +1,52 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef SOUND_FIREWIRE_CMP_H_INCLUDED +#define SOUND_FIREWIRE_CMP_H_INCLUDED + +#include +#include +#include "iso-resources.h" + +struct fw_unit; + +enum cmp_direction { + CMP_INPUT = 0, + CMP_OUTPUT, +}; + +/** + * struct cmp_connection - manages an isochronous connection to a device + * @speed: the connection's actual speed + * + * This structure manages (using CMP) an isochronous stream between the local + * computer and a device's input plug (iPCR) and output plug (oPCR). + * + * There is no corresponding oPCR created on the local computer, so it is not + * possible to overlay connections on top of this one. + */ +struct cmp_connection { + int speed; + /* private: */ + bool connected; + struct mutex mutex; + struct fw_iso_resources resources; + __be32 last_pcr_value; + unsigned int pcr_index; + unsigned int max_speed; + enum cmp_direction direction; +}; + +int cmp_connection_init(struct cmp_connection *connection, + struct fw_unit *unit, + enum cmp_direction direction, + unsigned int pcr_index); +int cmp_connection_check_used(struct cmp_connection *connection, bool *used); +void cmp_connection_destroy(struct cmp_connection *connection); + +int cmp_connection_reserve(struct cmp_connection *connection, + unsigned int max_payload); +void cmp_connection_release(struct cmp_connection *connection); + +int cmp_connection_establish(struct cmp_connection *connection); +void cmp_connection_break(struct cmp_connection *connection); + +#endif -- cgit v1.3.1