[14/15] asm-generic: hyperv: Use mshv headers conditionally. Add asm-generic/hyperv-defs.h
Commit Message
In order to keep unstable hyper-v interfaces independent of
hyperv-tlfs.h, hvhdk.h must replace hyperv-tlfs.h eveywhere it will be
used in the mshv driver.
Add hyperv-defs.h to replace some inclusions of hyperv-tlfs.h.
It includes hyperv-tlfs.h or hvhdk.h depending on a compile-time constant
HV_HYPERV_DEFS which will be defined in the mshv driver.
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
---
arch/arm64/include/asm/mshyperv.h | 2 +-
arch/x86/include/asm/mshyperv.h | 3 +--
drivers/hv/hyperv_vmbus.h | 1 -
include/asm-generic/hyperv-defs.h | 26 ++++++++++++++++++++++++++
include/asm-generic/mshyperv.h | 2 +-
include/linux/hyperv.h | 2 +-
6 files changed, 30 insertions(+), 6 deletions(-)
create mode 100644 include/asm-generic/hyperv-defs.h
Comments
On Thu, Jul 27, 2023 at 12:54:49PM -0700, Nuno Das Neves wrote:
> In order to keep unstable hyper-v interfaces independent of
> hyperv-tlfs.h, hvhdk.h must replace hyperv-tlfs.h eveywhere it will be
> used in the mshv driver.
Please properly capitalize "Hyper-V" when it is used as a term.
> Add hyperv-defs.h to replace some inclusions of hyperv-tlfs.h.
> It includes hyperv-tlfs.h or hvhdk.h depending on a compile-time constant
> HV_HYPERV_DEFS which will be defined in the mshv driver.
>
> Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
> ---
> arch/arm64/include/asm/mshyperv.h | 2 +-
> arch/x86/include/asm/mshyperv.h | 3 +--
> drivers/hv/hyperv_vmbus.h | 1 -
> include/asm-generic/hyperv-defs.h | 26 ++++++++++++++++++++++++++
> include/asm-generic/mshyperv.h | 2 +-
> include/linux/hyperv.h | 2 +-
> 6 files changed, 30 insertions(+), 6 deletions(-)
> create mode 100644 include/asm-generic/hyperv-defs.h
>
[...]
> diff --git a/include/asm-generic/hyperv-defs.h b/include/asm-generic/hyperv-defs.h
> new file mode 100644
> index 000000000000..ac6fcba35c8c
> --- /dev/null
> +++ b/include/asm-generic/hyperv-defs.h
> @@ -0,0 +1,26 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _ASM_GENERIC_HYPERV_DEFS_H
> +#define _ASM_GENERIC_HYPERV_DEFS_H
> +
> +/*
> + * There are cases where Microsoft Hypervisor ABIs are needed which may not be
> + * stable or present in the Hyper-V TLFS document. E.g. the mshv_root driver.
> + *
> + * As these interfaces are unstable and may differ from hyperv-tlfs.h, they
> + * must be kept separate and independent.
> + *
> + * However, code from files that depend on hyperv-tlfs.h (such as mshyperv.h)
> + * is still needed, so work around the issue by conditionally including the
> + * correct definitions.
> + *
> + * Note: Since they are independent of each other, there are many definitions
> + * duplicated in both hyperv-tlfs.h and uapi/hyperv/hv*.h files.
> + */
Is this because we accidentally introduced some host only, unstable
interfaces to hyperv-tlfs.h? Is the long term plan to drop those from
hyperv-tlfs.h and further separate the helper functions?
Thanks,
Wei.
> +#ifdef HV_HYPERV_DEFS
> +#include <uapi/hyperv/hvhdk.h>
> +#else
> +#include <asm/hyperv-tlfs.h>
> +#endif
> +
> +#endif /* _ASM_GENERIC_HYPERV_DEFS_H */
> +
> diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
> index 2b20994d809e..e86b6f51fb64 100644
> --- a/include/asm-generic/mshyperv.h
> +++ b/include/asm-generic/mshyperv.h
> @@ -25,7 +25,7 @@
> #include <linux/cpumask.h>
> #include <linux/nmi.h>
> #include <asm/ptrace.h>
> -#include <asm/hyperv-tlfs.h>
> +#include <asm-generic/hyperv-defs.h>
>
> #define VTPM_BASE_ADDRESS 0xfed40000
>
> diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
> index f90de5abcd50..66ed8b3e5d89 100644
> --- a/include/linux/hyperv.h
> +++ b/include/linux/hyperv.h
> @@ -24,7 +24,7 @@
> #include <linux/mod_devicetable.h>
> #include <linux/interrupt.h>
> #include <linux/reciprocal_div.h>
> -#include <asm/hyperv-tlfs.h>
> +#include <asm-generic/hyperv-defs.h>
>
> #define MAX_PAGE_BUFFER_COUNT 32
> #define MAX_MULTIPAGE_BUFFER_COUNT 32 /* 128K */
> --
> 2.25.1
>
@@ -20,7 +20,7 @@
#include <linux/types.h>
#include <linux/arm-smccc.h>
-#include <asm/hyperv-tlfs.h>
+#include <asm-generic/hyperv-defs.h>
/*
* Declare calls to get and set Hyper-V VP register values on ARM64, which
@@ -6,10 +6,9 @@
#include <linux/nmi.h>
#include <linux/msi.h>
#include <asm/io.h>
-#include <asm/hyperv-tlfs.h>
#include <asm/nospec-branch.h>
#include <asm/paravirt.h>
-#include <asm/mshyperv.h>
+#include <asm-generic/hyperv-defs.h>
/*
* Hyper-V always provides a single IO-APIC at this MMIO address.
@@ -15,7 +15,6 @@
#include <linux/list.h>
#include <linux/bitops.h>
#include <asm/sync_bitops.h>
-#include <asm/hyperv-tlfs.h>
#include <linux/atomic.h>
#include <linux/hyperv.h>
#include <linux/interrupt.h>
new file mode 100644
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_GENERIC_HYPERV_DEFS_H
+#define _ASM_GENERIC_HYPERV_DEFS_H
+
+/*
+ * There are cases where Microsoft Hypervisor ABIs are needed which may not be
+ * stable or present in the Hyper-V TLFS document. E.g. the mshv_root driver.
+ *
+ * As these interfaces are unstable and may differ from hyperv-tlfs.h, they
+ * must be kept separate and independent.
+ *
+ * However, code from files that depend on hyperv-tlfs.h (such as mshyperv.h)
+ * is still needed, so work around the issue by conditionally including the
+ * correct definitions.
+ *
+ * Note: Since they are independent of each other, there are many definitions
+ * duplicated in both hyperv-tlfs.h and uapi/hyperv/hv*.h files.
+ */
+#ifdef HV_HYPERV_DEFS
+#include <uapi/hyperv/hvhdk.h>
+#else
+#include <asm/hyperv-tlfs.h>
+#endif
+
+#endif /* _ASM_GENERIC_HYPERV_DEFS_H */
+
@@ -25,7 +25,7 @@
#include <linux/cpumask.h>
#include <linux/nmi.h>
#include <asm/ptrace.h>
-#include <asm/hyperv-tlfs.h>
+#include <asm-generic/hyperv-defs.h>
#define VTPM_BASE_ADDRESS 0xfed40000
@@ -24,7 +24,7 @@
#include <linux/mod_devicetable.h>
#include <linux/interrupt.h>
#include <linux/reciprocal_div.h>
-#include <asm/hyperv-tlfs.h>
+#include <asm-generic/hyperv-defs.h>
#define MAX_PAGE_BUFFER_COUNT 32
#define MAX_MULTIPAGE_BUFFER_COUNT 32 /* 128K */