diff options
| author | Nuno Das Neves <nunodasneves@linux.microsoft.com> | 2025-02-21 22:56:35 +0300 |
|---|---|---|
| committer | Wei Liu <wei.liu@kernel.org> | 2025-03-21 00:22:58 +0300 |
| commit | 461fbbd036b11d755b50e2ef7c165859a0f908d5 (patch) | |
| tree | caa25ffab490e20c17207d34de3c6543deae1564 /include | |
| parent | db912b8954c23a55dbc6dc683e0e06ffcb433848 (diff) | |
| download | linux-461fbbd036b11d755b50e2ef7c165859a0f908d5.tar.xz | |
hyperv: Add CONFIG_MSHV_ROOT to gate root partition support
CONFIG_MSHV_ROOT allows kernels built to run as a normal Hyper-V guest
to exclude the root partition code, which is expected to grow
significantly over time.
This option is a tristate so future driver code can be built as a
(m)odule, allowing faster development iteration cycles.
If CONFIG_MSHV_ROOT is disabled, don't compile hv_proc.c, and stub
hv_root_partition() to return false unconditionally. This allows the
compiler to optimize away root partition code blocks since they will
be disabled at compile time.
In the case of booting as root partition *without* CONFIG_MSHV_ROOT
enabled, print a critical error (the kernel will likely crash).
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Easwar Hariharan <eahariha@linux.microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/1740167795-13296-4-git-send-email-nunodasneves@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <1740167795-13296-4-git-send-email-nunodasneves@linux.microsoft.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-generic/mshyperv.h | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h index 54ebd630e72c..b13b0cda4ac8 100644 --- a/include/asm-generic/mshyperv.h +++ b/include/asm-generic/mshyperv.h @@ -223,10 +223,6 @@ void *hv_alloc_hyperv_page(void); void *hv_alloc_hyperv_zeroed_page(void); void hv_free_hyperv_page(void *addr); -int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages); -int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id); -int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags); - /** * hv_cpu_number_to_vp_number() - Map CPU to VP. * @cpu_number: CPU number in Linux terms @@ -327,9 +323,29 @@ static inline enum hv_isolation_type hv_get_isolation_type(void) } #endif /* CONFIG_HYPERV */ +#if IS_ENABLED(CONFIG_MSHV_ROOT) static inline bool hv_root_partition(void) { return hv_curr_partition_type == HV_PARTITION_TYPE_ROOT; } +int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages); +int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id); +int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags); + +#else /* CONFIG_MSHV_ROOT */ +static inline bool hv_root_partition(void) { return false; } +static inline int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages) +{ + return -EOPNOTSUPP; +} +static inline int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id) +{ + return -EOPNOTSUPP; +} +static inline int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags) +{ + return -EOPNOTSUPP; +} +#endif /* CONFIG_MSHV_ROOT */ #endif |