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| author | Zeng Chi <zengchi@kylinos.cn> | 2026-09-21 18:24:42 +0800 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2026-09-22 08:36:16 -0700 |
| commit | 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d (patch) | |
| tree | 660d50d4139cb750fbde1ae3432452c20726c99d /include/acpi/pcc.h | |
| download | linux-stable-119e9db233ad0f4cbd4cfb9f9385a7bca378b37d.tar.gz linux-stable-119e9db233ad0f4cbd4cfb9f9385a7bca378b37d.zip | |
KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted
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 <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'include/acpi/pcc.h')
| -rw-r--r-- | include/acpi/pcc.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/include/acpi/pcc.h b/include/acpi/pcc.h new file mode 100644 index 000000000..840bfc95b --- /dev/null +++ b/include/acpi/pcc.h @@ -0,0 +1,49 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * PCC (Platform Communications Channel) methods + */ + +#ifndef _PCC_H +#define _PCC_H + +#include <linux/mailbox_controller.h> +#include <linux/mailbox_client.h> + +struct pcc_mbox_chan { + struct mbox_chan *mchan; + u64 shmem_base_addr; + void __iomem *shmem; + u64 shmem_size; + u32 latency; + u32 max_access_rate; + u16 min_turnaround_time; +}; + +/* Generic Communications Channel Shared Memory Region */ +#define PCC_SIGNATURE 0x50434300 +/* Generic Communications Channel Command Field */ +#define PCC_CMD_GENERATE_DB_INTR BIT(15) +/* Generic Communications Channel Status Field */ +#define PCC_STATUS_CMD_COMPLETE BIT(0) +#define PCC_STATUS_SCI_DOORBELL BIT(1) +#define PCC_STATUS_ERROR BIT(2) +#define PCC_STATUS_PLATFORM_NOTIFY BIT(3) +/* Initiator Responder Communications Channel Flags */ +#define PCC_CMD_COMPLETION_NOTIFY BIT(0) + +#define MAX_PCC_SUBSPACES 256 + +#ifdef CONFIG_PCC +extern struct pcc_mbox_chan * +pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id); +extern void pcc_mbox_free_channel(struct pcc_mbox_chan *chan); +#else +static inline struct pcc_mbox_chan * +pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id) +{ + return ERR_PTR(-ENODEV); +} +static inline void pcc_mbox_free_channel(struct pcc_mbox_chan *chan) { } +#endif + +#endif /* _PCC_H */ |