We will need the partition ID for executing some hypercalls later.
Signed-off-by: Lillian Grassin-Drake <[email protected]>
Co-Developed-by: Sunil Muthuswamy <[email protected]>
Signed-off-by: Wei Liu <[email protected]>
---
arch/x86/hyperv/hv_init.c | 26 ++++++++++++++++++++++++++
arch/x86/include/asm/mshyperv.h | 2 ++
include/asm-generic/hyperv-tlfs.h | 6 ++++++
3 files changed, 34 insertions(+)
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index ebba4be4185d..0eec1ed32023 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -30,6 +30,9 @@
bool hv_root_partition;
EXPORT_SYMBOL_GPL(hv_root_partition);
+u64 hv_current_partition_id;
+EXPORT_SYMBOL_GPL(hv_current_partition_id);
+
void *hv_hypercall_pg;
EXPORT_SYMBOL_GPL(hv_hypercall_pg);
@@ -345,6 +348,26 @@ static struct syscore_ops hv_syscore_ops = {
.resume = hv_resume,
};
+void __init hv_get_partition_id(void)
+{
+ struct hv_get_partition_id *output_page;
+ int status;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ output_page = *this_cpu_ptr(hyperv_pcpu_output_arg);
+ status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page) &
+ HV_HYPERCALL_RESULT_MASK;
+ if (status != HV_STATUS_SUCCESS)
+ pr_err("Failed to get partition ID: %d\n", status);
+ else
+ hv_current_partition_id = output_page->partition_id;
+ local_irq_restore(flags);
+
+ /* No point in proceeding if this failed */
+ BUG_ON(status != HV_STATUS_SUCCESS);
+}
+
/*
* This function is to be invoked early in the boot sequence after the
* hypervisor has been detected.
@@ -440,6 +463,9 @@ void __init hyperv_init(void)
register_syscore_ops(&hv_syscore_ops);
+ if (hv_root_partition)
+ hv_get_partition_id();
+
return;
remove_cpuhp_state:
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index f5c62140f28d..4039302e0ae9 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -65,6 +65,8 @@ extern void *hv_hypercall_pg;
extern void __percpu **hyperv_pcpu_input_arg;
extern void __percpu **hyperv_pcpu_output_arg;
+extern u64 hv_current_partition_id;
+
static inline u64 hv_do_hypercall(u64 control, void *input, void *output)
{
u64 input_address = input ? virt_to_phys(input) : 0;
diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h
index e6903589a82a..87b1a79b19eb 100644
--- a/include/asm-generic/hyperv-tlfs.h
+++ b/include/asm-generic/hyperv-tlfs.h
@@ -141,6 +141,7 @@ struct ms_hyperv_tsc_page {
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX 0x0013
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX 0x0014
#define HVCALL_SEND_IPI_EX 0x0015
+#define HVCALL_GET_PARTITION_ID 0x0046
#define HVCALL_GET_VP_REGISTERS 0x0050
#define HVCALL_SET_VP_REGISTERS 0x0051
#define HVCALL_POST_MESSAGE 0x005c
@@ -407,6 +408,11 @@ struct hv_tlb_flush_ex {
u64 gva_list[];
} __packed;
+/* HvGetPartitionId hypercall (output only) */
+struct hv_get_partition_id {
+ u64 partition_id;
+} __packed;
+
/* HvRetargetDeviceInterrupt hypercall */
union hv_msi_entry {
u64 as_uint64;
--
2.20.1
Wei Liu <[email protected]> writes:
> We will need the partition ID for executing some hypercalls later.
>
> Signed-off-by: Lillian Grassin-Drake <[email protected]>
> Co-Developed-by: Sunil Muthuswamy <[email protected]>
> Signed-off-by: Wei Liu <[email protected]>
> ---
> arch/x86/hyperv/hv_init.c | 26 ++++++++++++++++++++++++++
> arch/x86/include/asm/mshyperv.h | 2 ++
> include/asm-generic/hyperv-tlfs.h | 6 ++++++
> 3 files changed, 34 insertions(+)
>
> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> index ebba4be4185d..0eec1ed32023 100644
> --- a/arch/x86/hyperv/hv_init.c
> +++ b/arch/x86/hyperv/hv_init.c
> @@ -30,6 +30,9 @@
> bool hv_root_partition;
> EXPORT_SYMBOL_GPL(hv_root_partition);
>
> +u64 hv_current_partition_id;
> +EXPORT_SYMBOL_GPL(hv_current_partition_id);
> +
> void *hv_hypercall_pg;
> EXPORT_SYMBOL_GPL(hv_hypercall_pg);
>
> @@ -345,6 +348,26 @@ static struct syscore_ops hv_syscore_ops = {
> .resume = hv_resume,
> };
>
> +void __init hv_get_partition_id(void)
> +{
> + struct hv_get_partition_id *output_page;
> + int status;
> + unsigned long flags;
> +
> + local_irq_save(flags);
> + output_page = *this_cpu_ptr(hyperv_pcpu_output_arg);
> + status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page) &
> + HV_HYPERCALL_RESULT_MASK;
Nit: in this case status is 'u16', we can define it as such (instead of
signed int).
> + if (status != HV_STATUS_SUCCESS)
> + pr_err("Failed to get partition ID: %d\n", status);
> + else
> + hv_current_partition_id = output_page->partition_id;
> + local_irq_restore(flags);
> +
> + /* No point in proceeding if this failed */
> + BUG_ON(status != HV_STATUS_SUCCESS);
> +}
> +
> /*
> * This function is to be invoked early in the boot sequence after the
> * hypervisor has been detected.
> @@ -440,6 +463,9 @@ void __init hyperv_init(void)
>
> register_syscore_ops(&hv_syscore_ops);
>
> + if (hv_root_partition)
> + hv_get_partition_id();
According to TLFS, partition ID is available when AccessPartitionId
privilege is granted. I'd suggest we check that instead of
hv_root_partition (and we can set hv_current_partition_id to something
like U64_MAX so we know it wasn't acuired). So the BUG_ON condition will
move here:
hv_get_partition_id();
BUG_ON(hv_root_partition && hv_current_partition_id == U64_MAX);
> +
> return;
>
> remove_cpuhp_state:
> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> index f5c62140f28d..4039302e0ae9 100644
> --- a/arch/x86/include/asm/mshyperv.h
> +++ b/arch/x86/include/asm/mshyperv.h
> @@ -65,6 +65,8 @@ extern void *hv_hypercall_pg;
> extern void __percpu **hyperv_pcpu_input_arg;
> extern void __percpu **hyperv_pcpu_output_arg;
>
> +extern u64 hv_current_partition_id;
> +
> static inline u64 hv_do_hypercall(u64 control, void *input, void *output)
> {
> u64 input_address = input ? virt_to_phys(input) : 0;
> diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h
> index e6903589a82a..87b1a79b19eb 100644
> --- a/include/asm-generic/hyperv-tlfs.h
> +++ b/include/asm-generic/hyperv-tlfs.h
> @@ -141,6 +141,7 @@ struct ms_hyperv_tsc_page {
> #define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX 0x0013
> #define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX 0x0014
> #define HVCALL_SEND_IPI_EX 0x0015
> +#define HVCALL_GET_PARTITION_ID 0x0046
> #define HVCALL_GET_VP_REGISTERS 0x0050
> #define HVCALL_SET_VP_REGISTERS 0x0051
> #define HVCALL_POST_MESSAGE 0x005c
> @@ -407,6 +408,11 @@ struct hv_tlb_flush_ex {
> u64 gva_list[];
> } __packed;
>
> +/* HvGetPartitionId hypercall (output only) */
> +struct hv_get_partition_id {
> + u64 partition_id;
> +} __packed;
> +
> /* HvRetargetDeviceInterrupt hypercall */
> union hv_msi_entry {
> u64 as_uint64;
--
Vitaly
On Tue, Sep 15, 2020 at 12:27:16PM +0200, Vitaly Kuznetsov wrote:
> Wei Liu <[email protected]> writes:
[...]
> >
> > +void __init hv_get_partition_id(void)
> > +{
> > + struct hv_get_partition_id *output_page;
> > + int status;
> > + unsigned long flags;
> > +
> > + local_irq_save(flags);
> > + output_page = *this_cpu_ptr(hyperv_pcpu_output_arg);
> > + status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page) &
> > + HV_HYPERCALL_RESULT_MASK;
>
> Nit: in this case status is 'u16', we can define it as such (instead of
> signed int).
Fixed.
>
> > + if (status != HV_STATUS_SUCCESS)
> > + pr_err("Failed to get partition ID: %d\n", status);
> > + else
> > + hv_current_partition_id = output_page->partition_id;
> > + local_irq_restore(flags);
> > +
> > + /* No point in proceeding if this failed */
> > + BUG_ON(status != HV_STATUS_SUCCESS);
> > +}
> > +
> > /*
> > * This function is to be invoked early in the boot sequence after the
> > * hypervisor has been detected.
> > @@ -440,6 +463,9 @@ void __init hyperv_init(void)
> >
> > register_syscore_ops(&hv_syscore_ops);
> >
> > + if (hv_root_partition)
> > + hv_get_partition_id();
>
> According to TLFS, partition ID is available when AccessPartitionId
> privilege is granted. I'd suggest we check that instead of
> hv_root_partition (and we can set hv_current_partition_id to something
> like U64_MAX so we know it wasn't acuired). So the BUG_ON condition will
> move here:
>
> hv_get_partition_id();
> BUG_ON(hv_root_partition && hv_current_partition_id == U64_MAX);
>
Good point. I will reorganize this a bit.
Wei.
On Wed, Sep 16, 2020 at 04:32:43PM +0000, Wei Liu wrote:
> On Tue, Sep 15, 2020 at 12:27:16PM +0200, Vitaly Kuznetsov wrote:
> > Wei Liu <[email protected]> writes:
> [...]
> > >
> > > +void __init hv_get_partition_id(void)
> > > +{
> > > + struct hv_get_partition_id *output_page;
> > > + int status;
> > > + unsigned long flags;
> > > +
> > > + local_irq_save(flags);
> > > + output_page = *this_cpu_ptr(hyperv_pcpu_output_arg);
> > > + status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page) &
> > > + HV_HYPERCALL_RESULT_MASK;
> >
> > Nit: in this case status is 'u16', we can define it as such (instead of
> > signed int).
>
> Fixed.
>
> >
> > > + if (status != HV_STATUS_SUCCESS)
> > > + pr_err("Failed to get partition ID: %d\n", status);
> > > + else
> > > + hv_current_partition_id = output_page->partition_id;
> > > + local_irq_restore(flags);
> > > +
> > > + /* No point in proceeding if this failed */
> > > + BUG_ON(status != HV_STATUS_SUCCESS);
> > > +}
> > > +
> > > /*
> > > * This function is to be invoked early in the boot sequence after the
> > > * hypervisor has been detected.
> > > @@ -440,6 +463,9 @@ void __init hyperv_init(void)
> > >
> > > register_syscore_ops(&hv_syscore_ops);
> > >
> > > + if (hv_root_partition)
> > > + hv_get_partition_id();
> >
> > According to TLFS, partition ID is available when AccessPartitionId
> > privilege is granted. I'd suggest we check that instead of
> > hv_root_partition (and we can set hv_current_partition_id to something
> > like U64_MAX so we know it wasn't acuired). So the BUG_ON condition will
> > move here:
> >
> > hv_get_partition_id();
> > BUG_ON(hv_root_partition && hv_current_partition_id == U64_MAX);
> >
>
> Good point. I will reorganize this a bit.
Actually, our current code never stashed the feature mask that contains
that privilege anywhere. Getting access to it will require a few more
extra patches -- I would really like to rename those fields (features,
misc_features) inside ms_hyperv to something more appropriate.
We will gate it wit hv_root_partition anyway, since we a child VM may
not have the privilege, making an unconditional BUG_ON fatal.
All in all, the current code is not too bad. I intend to keep the
current structure for my RFC v2. I will see if I can find some time to
rework the feature mask extraction code and get that upstreamed first.
Wei.
>
> Wei.