On 2/8/2021 11:48 AM, Michael Kelley wrote:
> From: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx> Sent: Friday, November 20, 2020 4:31 PM
>> To: linux-hyperv@xxxxxxxxxxxxxxx
>> Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Michael Kelley
>> <mikelley@xxxxxxxxxxxxx>; viremana@xxxxxxxxxxxxxxxxxxx; Sunil Muthuswamy
>> <sunilmut@xxxxxxxxxxxxx>; nunodasneves@xxxxxxxxxxxxxxxxxxx; wei.liu@xxxxxxxxxx;
>> Lillian Grassin-Drake <Lillian.GrassinDrake@xxxxxxxxxxxxx>; KY Srinivasan
>> <kys@xxxxxxxxxxxxx>
>> Subject: [RFC PATCH 15/18] virt/mshv: get and set vp state ioctls
>>
>> Introduce ioctls for getting and setting guest vcpu emulated LAPIC
>> state, and xsave data.
>>
>> Signed-off-by: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx>
>> ---
>> Documentation/virt/mshv/api.rst | 8 +
>> arch/x86/include/uapi/asm/hyperv-tlfs.h | 59 ++++++
>> include/asm-generic/hyperv-tlfs.h | 41 ++++
>> include/uapi/asm-generic/hyperv-tlfs.h | 28 +++
>> include/uapi/linux/mshv.h | 13 ++
>> virt/mshv/mshv_main.c | 262 ++++++++++++++++++++++++
>> 6 files changed, 411 insertions(+)
>>
>> diff --git a/Documentation/virt/mshv/api.rst b/Documentation/virt/mshv/api.rst
>> index 694f978131f9..7fd75f248eff 100644
>> --- a/Documentation/virt/mshv/api.rst
>> +++ b/Documentation/virt/mshv/api.rst
>> @@ -140,4 +140,12 @@ Assert interrupts in partitions that use Microsoft Hypervisor's
>> internal
>> emulated LAPIC. This must be enabled on partition creation with the flag:
>> HV_PARTITION_CREATION_FLAG_LAPIC_ENABLED
>>
>> +3.9 MSHV_GET_VP_STATE and MSHV_SET_VP_STATE
>> +--------------------------
>> +:Type: vp ioctl
>> +:Parameters: struct mshv_vp_state
>> +:Returns: 0 on success
>> +
>> +Get/set various vp state. Currently these can be used to get and set
>> +emulated LAPIC state, and xsave data.
>>
>> diff --git a/arch/x86/include/uapi/asm/hyperv-tlfs.h b/arch/x86/include/uapi/asm/hyperv-
>> tlfs.h
>> index 5478d4943bfc..78758aedf23e 100644
>> --- a/arch/x86/include/uapi/asm/hyperv-tlfs.h
>> +++ b/arch/x86/include/uapi/asm/hyperv-tlfs.h
>> @@ -1051,4 +1051,63 @@ union hv_interrupt_control {
>> __u64 as_uint64;
>> };
>>
>> +struct hv_local_interrupt_controller_state {
>> + __u32 apic_id;
>> + __u32 apic_version;
>> + __u32 apic_ldr;
>> + __u32 apic_dfr;
>> + __u32 apic_spurious;
>> + __u32 apic_isr[8];
>> + __u32 apic_tmr[8];
>> + __u32 apic_irr[8];
>> + __u32 apic_esr;
>> + __u32 apic_icr_high;
>> + __u32 apic_icr_low;
>> + __u32 apic_lvt_timer;
>> + __u32 apic_lvt_thermal;
>> + __u32 apic_lvt_perfmon;
>> + __u32 apic_lvt_lint0;
>> + __u32 apic_lvt_lint1;
>> + __u32 apic_lvt_error;
>> + __u32 apic_lvt_cmci;
>> + __u32 apic_error_status;
>> + __u32 apic_initial_count;
>> + __u32 apic_counter_value;
>> + __u32 apic_divide_configuration;
>> + __u32 apic_remote_read;
>> +};
>> +
>> +#define HV_XSAVE_DATA_NO_XMM_REGISTERS 1
>> +
>> +union hv_x64_xsave_xfem_register {
>> + __u64 as_uint64;
>> + struct {
>> + __u32 low_uint32;
>> + __u32 high_uint32;
>> + };
>> + struct {
>> + __u64 legacy_x87: 1;
>> + __u64 legacy_sse: 1;
>> + __u64 avx: 1;
>> + __u64 mpx_bndreg: 1;
>> + __u64 mpx_bndcsr: 1;
>> + __u64 avx_512_op_mask: 1;
>> + __u64 avx_512_zmmhi: 1;
>> + __u64 avx_512_zmm16_31: 1;
>> + __u64 rsvd8_9: 2;
>> + __u64 pasid: 1;
>> + __u64 cet_u: 1;
>> + __u64 cet_s: 1;
>> + __u64 rsvd13_16: 4;
>> + __u64 xtile_cfg: 1;
>> + __u64 xtile_data: 1;
>> + __u64 rsvd19_63: 45;
>> + };
>> +};
>> +
>> +struct hv_vp_state_data_xsave {
>> + __u64 flags;
>> + union hv_x64_xsave_xfem_register states;
>> +};
>> +
>> #endif
>> diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h
>> index 2cd46241c545..4bc59a0344ce 100644
>> --- a/include/asm-generic/hyperv-tlfs.h
>> +++ b/include/asm-generic/hyperv-tlfs.h
>> @@ -167,6 +167,9 @@ struct ms_hyperv_tsc_page {
>> #define HVCALL_ASSERT_VIRTUAL_INTERRUPT 0x0094
>> #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE 0x00af
>> #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST 0x00b0
>> +#define HVCALL_MAP_VP_STATE_PAGE 0x00e1
>> +#define HVCALL_GET_VP_STATE 0x00e3
>> +#define HVCALL_SET_VP_STATE 0x00e4
>>
>> #define HV_FLUSH_ALL_PROCESSORS BIT(0)
>> #define HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES BIT(1)
>> @@ -796,4 +799,42 @@ struct hv_assert_virtual_interrupt {
>> u16 rsvd_z1;
>> };
>>
>> +struct hv_vp_state_data {
>> + enum hv_get_set_vp_state_type type;
>> + u32 rsvd;
>> + struct hv_vp_state_data_xsave xsave;
>> +
>> +};
>> +
>> +struct hv_get_vp_state_in {
>> + u64 partition_id;
>> + u32 vp_index;
>> + u8 input_vtl;
>> + u8 rsvd0;
>> + u16 rsvd1;
>> + struct hv_vp_state_data state_data;
>> + u64 output_data_pfns[];
>> +};
>> +
>> +union hv_get_vp_state_out {
>> + struct hv_local_interrupt_controller_state interrupt_controller_state;
>> + /* Not supported yet */
>> + /* struct hv_synthetic_timers_state synthetic_timers_state; */
>> +};
>> +
>> +union hv_input_set_vp_state_data {
>> + u64 pfns;
>> + u8 bytes;
>> +};
>> +
>> +struct hv_set_vp_state_in {
>> + u64 partition_id;
>> + u32 vp_index;
>> + u8 input_vtl;
>> + u8 rsvd0;
>> + u16 rsvd1;
>> + struct hv_vp_state_data state_data;
>> + union hv_input_set_vp_state_data data[];
>> +};
>> +
>> #endif
>> diff --git a/include/uapi/asm-generic/hyperv-tlfs.h b/include/uapi/asm-generic/hyperv-
>> tlfs.h
>> index e87389054b68..b3c84c69b73f 100644
>> --- a/include/uapi/asm-generic/hyperv-tlfs.h
>> +++ b/include/uapi/asm-generic/hyperv-tlfs.h
>> @@ -64,4 +64,32 @@ struct hv_message {
>> #define HV_MAP_GPA_EXECUTABLE 0xC
>> #define HV_MAP_GPA_PERMISSIONS_MASK 0xF
>>
>> +/*
>> + * For getting and setting VP state, there are two options based on the state type:
>> + *
>> + * 1.) Data that is accessed by PFNs in the input hypercall page. This is used
>> + * for state which may not fit into the hypercall pages.
>> + * 2.) Data that is accessed directly in the input\output hypercall pages.
>> + * This is used for state that will always fit into the hypercall pages.
>> + *
>> + * In the future this could be dynamic based on the size if needed.
>> + *
>> + * Note these hypercalls have an 8-byte aligned variable header size as per the tlfs
>> + */
>> +
>> +#define HV_GET_SET_VP_STATE_TYPE_PFN BIT(31)
>> +
>> +enum hv_get_set_vp_state_type {
>> + HV_GET_SET_VP_STATE_LOCAL_INTERRUPT_CONTROLLER_STATE = 0,
>> +
>> + HV_GET_SET_VP_STATE_XSAVE = 1 |
>> HV_GET_SET_VP_STATE_TYPE_PFN,
>> + /* Synthetic message page */
>> + HV_GET_SET_VP_STATE_SIM_PAGE = 2 |
>> HV_GET_SET_VP_STATE_TYPE_PFN,
>> + /* Synthetic interrupt event flags page. */
>> + HV_GET_SET_VP_STATE_SIEF_PAGE = 3 |
>> HV_GET_SET_VP_STATE_TYPE_PFN,
>> +
>> + /* Synthetic timers. */
>> + HV_GET_SET_VP_STATE_SYNTHETIC_TIMERS = 4,
>> +};
>> +
>> #endif
>> diff --git a/include/uapi/linux/mshv.h b/include/uapi/linux/mshv.h
>> index faed9d065bb7..ae0bb64bbec3 100644
>> --- a/include/uapi/linux/mshv.h
>> +++ b/include/uapi/linux/mshv.h
>> @@ -53,6 +53,17 @@ struct mshv_assert_interrupt {
>> __u32 vector;
>> };
>>
>> +struct mshv_vp_state {
>> + enum hv_get_set_vp_state_type type;
>> + struct hv_vp_state_data_xsave xsave; /* only for xsave request */
>> +
>> + __u64 buf_size; /* If xsave, must be page-aligned */
>> + union {
>> + struct hv_local_interrupt_controller_state *lapic;
>> + __u8 *bytes; /* Xsave data. must be page-aligned */
>> + } buf;
>> +};
>> +
>> #define MSHV_IOCTL 0xB8
>>
>> /* mshv device */
>> @@ -70,5 +81,7 @@ struct mshv_assert_interrupt {
>> #define MSHV_GET_VP_REGISTERS _IOWR(MSHV_IOCTL, 0x05, struct
>> mshv_vp_registers)
>> #define MSHV_SET_VP_REGISTERS _IOW(MSHV_IOCTL, 0x06, struct mshv_vp_registers)
>> #define MSHV_RUN_VP _IOR(MSHV_IOCTL, 0x07, struct hv_message)
>> +#define MSHV_GET_VP_STATE _IOWR(MSHV_IOCTL, 0x0A, struct mshv_vp_state)
>> +#define MSHV_SET_VP_STATE _IOWR(MSHV_IOCTL, 0x0B, struct mshv_vp_state)
>>
>> #endif
>> diff --git a/virt/mshv/mshv_main.c b/virt/mshv/mshv_main.c
>> index 9cf236ade50a..70172d9488de 100644
>> --- a/virt/mshv/mshv_main.c
>> +++ b/virt/mshv/mshv_main.c
>> @@ -864,6 +864,262 @@ mshv_vp_ioctl_set_regs(struct mshv_vp *vp, void __user
>> *user_args)
>> return ret;
>> }
>>
>> +static int
>> +hv_call_get_vp_state(u32 vp_index,
>> + u64 partition_id,
>> + enum hv_get_set_vp_state_type type,
>> + struct hv_vp_state_data_xsave xsave,
>> + /* Choose between pages and ret_output */
>> + u64 page_count,
>> + struct page **pages,
>> + union hv_get_vp_state_out *ret_output)
>> +{
>> + struct hv_get_vp_state_in *input;
>> + union hv_get_vp_state_out *output;
>> + int status;
>> + int i;
>> + u64 control;
>> + unsigned long flags;
>> + int ret = 0;
>> +
>> + if (sizeof(*input) + (page_count * sizeof(u64)) > PAGE_SIZE)
>> + return -EINVAL;
>
> Nit: Stylistically, you are handling this differently from the BATCH_SIZE
> macros, which are essentially doing the same thing of calculating
> how many entries will fit in the input page. Note to use
> HV_HYP_PAGE_SIZE.
>
Hmm, I didn't notice this. I guess it's ok either way, but for consistency I will add:
#define HV_GET_VP_STATE_BATCH_SIZE ((HV_HYP_PAGE_SIZE - sizeof(struct hv_get_vp_state_in)) / sizeof(u64))
And change the condition to:
if (page_count > HV_GET_VP_STATE_BATCH_SIZE)
>> +
>> + if (!page_count && !ret_output)
>> + return -EINVAL;
>> +
>> + do {
>> + local_irq_save(flags);
>> + input = (struct hv_get_vp_state_in *)
>> + (*this_cpu_ptr(hyperv_pcpu_input_arg));
>> + output = (union hv_get_vp_state_out *)
>> + (*this_cpu_ptr(hyperv_pcpu_output_arg));
>> + memset(input, 0, sizeof(*input));
>> + memset(output, 0, sizeof(*output));
>> +
>> + input->partition_id = partition_id;
>> + input->vp_index = vp_index;
>> + input->state_data.type = type;
>> + memcpy(&input->state_data.xsave, &xsave, sizeof(xsave));
>> + for (i = 0; i < page_count; i++)
>> + input->output_data_pfns[i] =
>> + page_to_pfn(pages[i]) & HV_MAP_GPA_MASK;
>> +
>> + control = (HVCALL_GET_VP_STATE) |
>> + (page_count << HV_HYPERCALL_VARHEAD_OFFSET);
>> +
>> + status = hv_do_hypercall(control, input, output) &
>> + HV_HYPERCALL_RESULT_MASK;
>> +
>> + if (status != HV_STATUS_INSUFFICIENT_MEMORY) {
>> + if (status != HV_STATUS_SUCCESS)
>> + pr_err("%s: %s\n", __func__,
>> + hv_status_to_string(status));
>> + else if (ret_output)
>> + memcpy(ret_output, output, sizeof(*output));
>> +
>> + local_irq_restore(flags);
>> + ret = -hv_status_to_errno(status);
>> + break;
>> + }
>> + local_irq_restore(flags);
>> +
>> + ret = hv_call_deposit_pages(NUMA_NO_NODE,
>> + partition_id, 1);
>> + } while (!ret);
>> +
>> + return ret;
>> +}
>> +
>> +static int
>> +hv_call_set_vp_state(u32 vp_index,
>> + u64 partition_id,
>> + enum hv_get_set_vp_state_type type,
>> + struct hv_vp_state_data_xsave xsave,
>> + /* Choose between pages and bytes */
>> + u64 page_count,
>> + struct page **pages,
>> + u32 num_bytes,
>> + u8 *bytes)
>> +{
>> + struct hv_set_vp_state_in *input;
>> + int status;
>> + int i;
>> + u64 control;
>> + unsigned long flags;
>> + int ret = 0;
>> + u16 varhead_sz;
>> +
>> + if (sizeof(*input) + (page_count * sizeof(u64)) > PAGE_SIZE)
>
> Same comment as above.
>
I'll do the same as above.
>> + return -EINVAL;
>> + if (sizeof(*input) + num_bytes > PAGE_SIZE)
>
> Use HV_HYP_PAGE_SIZE.
>
Will do.
>> + return -EINVAL;
>> +
>> + if (num_bytes)
>> + /* round up to 8 and divide by 8 */
>> + varhead_sz = (num_bytes + 7) >> 3;
>> + else if (page_count)
>> + varhead_sz = page_count;
>> + else
>> + return -EINVAL;
>> +
>> + do {
>> + local_irq_save(flags);
>> + input = (struct hv_set_vp_state_in *)
>> + (*this_cpu_ptr(hyperv_pcpu_input_arg));
>> + memset(input, 0, sizeof(*input));
>> +
>> + input->partition_id = partition_id;
>> + input->vp_index = vp_index;
>> + input->state_data.type = type;
>> + memcpy(&input->state_data.xsave, &xsave, sizeof(xsave));
>> + if (num_bytes) {
>> + memcpy((u8 *)input->data, bytes, num_bytes);
>> + } else {
>> + for (i = 0; i < page_count; i++)
>> + input->data[i].pfns =
>> + page_to_pfn(pages[i]) & HV_MAP_GPA_MASK;
>
> Same comment as in earlier patch about GPA_MASK. Also, this doesn't work
> if PAGE_SIZE != HV_HYP_PAGE_SIZE, though it may be fine to not handle that case
> for now.
>
Will remove the mask.
As before, won't handle PAGE_SIZE != HV_HYP_PAGE_SIZE in this patch set.
>> + }
>> +
>> + control = (HVCALL_SET_VP_STATE) |
>> + (varhead_sz << HV_HYPERCALL_VARHEAD_OFFSET);
>> +
>> + status = hv_do_hypercall(control, input, NULL) &
>> + HV_HYPERCALL_RESULT_MASK;
>> +
>> + if (status != HV_STATUS_INSUFFICIENT_MEMORY) {
>> + if (status != HV_STATUS_SUCCESS)
>> + pr_err("%s: %s\n", __func__,
>> + hv_status_to_string(status));
>> +
>> + local_irq_restore(flags);
>> + ret = -hv_status_to_errno(status);
>> + break;
>> + }
>> + local_irq_restore(flags);
>> +
>> + ret = hv_call_deposit_pages(NUMA_NO_NODE,
>> + partition_id, 1);
>> + } while (!ret);
>> +
>> + return ret;
>> +}
>> +
>> +static long
>> +mshv_vp_ioctl_get_set_state_pfn(struct mshv_vp *vp,
>> + struct mshv_vp_state *args,
>> + bool is_set)
>> +{
>> + u64 page_count, remaining;
>> + int completed;
>> + struct page **pages;
>> + long ret;
>> + unsigned long u_buf;
>> +
>> + /* Buffer must be page aligned */
>> + if (args->buf_size & (PAGE_SIZE - 1) ||
>> + (u64)args->buf.bytes & (PAGE_SIZE - 1))
>> + return -EINVAL;
>
> Use PAGE_ALIGNED macro.
>
Will do.
>> +
>> + if (!access_ok(args->buf.bytes, args->buf_size))
>> + return -EFAULT;
>> +
>> + /* Pin user pages so hypervisor can copy directly to them */
>> + page_count = args->buf_size >> PAGE_SHIFT;
>> + pages = kcalloc(page_count, sizeof(struct page *), GFP_KERNEL);
>> + if (!pages)
>> + return -ENOMEM;
>> +
>> + remaining = page_count;
>> + u_buf = (unsigned long)args->buf.bytes;
>> + while (remaining) {
>> + completed = pin_user_pages_fast(
>> + u_buf,
>> + remaining,
>> + FOLL_WRITE,
>> + &pages[page_count - remaining]);
>> + if (completed < 0) {
>> + pr_err("%s: failed to pin user pages error %i\n",
>> + __func__, completed);
>> + ret = completed;
>> + goto unpin_pages;
>> + }
>> + remaining -= completed;
>> + u_buf += completed * PAGE_SIZE;
>> + }
>> +
>> + if (is_set)
>> + ret = hv_call_set_vp_state(vp->index,
>> + vp->partition->id,
>> + args->type, args->xsave,
>> + page_count, pages,
>> + 0, NULL);
>> + else
>> + ret = hv_call_get_vp_state(vp->index,
>> + vp->partition->id,
>> + args->type, args->xsave,
>> + page_count, pages,
>> + NULL);
>> +
>> +unpin_pages:
>> + unpin_user_pages(pages, page_count - remaining);
>> + kfree(pages);
>> + return ret;
>> +}
>> +
>> +static long
>> +mshv_vp_ioctl_get_set_state(struct mshv_vp *vp, void __user *user_args, bool is_set)
>> +{
>> + struct mshv_vp_state args;
>> + long ret = 0;
>> + union hv_get_vp_state_out vp_state;
>> +
>> + if (copy_from_user(&args, user_args, sizeof(args)))
>> + return -EFAULT;
>> +
>> + /* For now just support these */
>> + if (args.type != HV_GET_SET_VP_STATE_LOCAL_INTERRUPT_CONTROLLER_STATE &&
>> + args.type != HV_GET_SET_VP_STATE_XSAVE)
>> + return -EINVAL;
>> +
>> + /* If we need to pin pfns, delegate to helper */
>> + if (args.type & HV_GET_SET_VP_STATE_TYPE_PFN)
>> + return mshv_vp_ioctl_get_set_state_pfn(vp, &args, is_set);
>> +
>> + if (args.buf_size < sizeof(vp_state))
>> + return -EINVAL;
>> +
>> + if (is_set) {
>> + if (copy_from_user(
>> + &vp_state,
>> + args.buf.lapic,
>> + sizeof(vp_state)))
>> + return -EFAULT;
>> +
>> + return hv_call_set_vp_state(vp->index,
>> + vp->partition->id,
>> + args.type, args.xsave,
>> + 0, NULL,
>> + sizeof(vp_state),
>> + (u8 *)&vp_state);
>> + }
>> +
>> + ret = hv_call_get_vp_state(vp->index,
>> + vp->partition->id,
>> + args.type, args.xsave,
>> + 0, NULL,
>> + &vp_state);
>> +
>> + if (ret)
>> + return ret;
>> +
>> + if (copy_to_user(args.buf.lapic,
>> + &vp_state.interrupt_controller_state,
>> + sizeof(vp_state.interrupt_controller_state)))
>> + return -EFAULT;
>> +
>> + return 0;
>> +}
>>
>> static long
>> mshv_vp_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
>> @@ -884,6 +1140,12 @@ mshv_vp_ioctl(struct file *filp, unsigned int ioctl, unsigned long
>> arg)
>> case MSHV_SET_VP_REGISTERS:
>> r = mshv_vp_ioctl_set_regs(vp, (void __user *)arg);
>> break;
>> + case MSHV_GET_VP_STATE:
>> + r = mshv_vp_ioctl_get_set_state(vp, (void __user *)arg, false);
>> + break;
>> + case MSHV_SET_VP_STATE:
>> + r = mshv_vp_ioctl_get_set_state(vp, (void __user *)arg, true);
>> + break;
>> default:
>> r = -ENOTTY;
>> break;
>> --
>> 2.25.1
