Wei Liu <wei....@kernel.org> writes:
> They are used to deposit pages into Microsoft Hypervisor and bring up
> logical and virtual processors.
>
> Signed-off-by: Lillian Grassin-Drake <ligra...@microsoft.com>
> Signed-off-by: Sunil Muthuswamy <sunil...@microsoft.com>
> Signed-off-by: Nuno Das Neves <nunodasne...@linux.microsoft.com>
> Co-Developed-by: Lillian Grassin-Drake <ligra...@microsoft.com>
> Co-Developed-by: Sunil Muthuswamy <sunil...@microsoft.com>
> Co-Developed-by: Nuno Das Neves <nunodasne...@linux.microsoft.com>
> Signed-off-by: Wei Liu <wei....@kernel.org>
> ---
> v2:
> 1. Adapt to hypervisor side changes
> 2. Address Vitaly's comments
> ---
> arch/x86/hyperv/Makefile | 2 +-
> arch/x86/hyperv/hv_proc.c | 217 ++++++++++++++++++++++++++++++
> arch/x86/include/asm/mshyperv.h | 4 +
> include/asm-generic/hyperv-tlfs.h | 67 +++++++++
> 4 files changed, 289 insertions(+), 1 deletion(-)
> create mode 100644 arch/x86/hyperv/hv_proc.c
>
> diff --git a/arch/x86/hyperv/Makefile b/arch/x86/hyperv/Makefile
> index 89b1f74d3225..565358020921 100644
> --- a/arch/x86/hyperv/Makefile
> +++ b/arch/x86/hyperv/Makefile
> @@ -1,6 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0-only
> obj-y := hv_init.o mmu.o nested.o
> -obj-$(CONFIG_X86_64) += hv_apic.o
> +obj-$(CONFIG_X86_64) += hv_apic.o hv_proc.o
>
> ifdef CONFIG_X86_64
> obj-$(CONFIG_PARAVIRT_SPINLOCKS) += hv_spinlock.o
> diff --git a/arch/x86/hyperv/hv_proc.c b/arch/x86/hyperv/hv_proc.c
> new file mode 100644
> index 000000000000..0fd972c9129a
> --- /dev/null
> +++ b/arch/x86/hyperv/hv_proc.c
> @@ -0,0 +1,217 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <linux/types.h>
> +#include <linux/version.h>
> +#include <linux/vmalloc.h>
> +#include <linux/mm.h>
> +#include <linux/clockchips.h>
> +#include <linux/acpi.h>
> +#include <linux/hyperv.h>
> +#include <linux/slab.h>
> +#include <linux/cpuhotplug.h>
> +#include <linux/minmax.h>
> +#include <asm/hypervisor.h>
> +#include <asm/mshyperv.h>
> +#include <asm/apic.h>
> +
> +#include <asm/trace/hyperv.h>
> +
> +#define HV_DEPOSIT_MAX_ORDER (8)
> +#define HV_DEPOSIT_MAX (1 << HV_DEPOSIT_MAX_ORDER)
> +
> +/*
> + * Deposits exact number of pages
> + * Must be called with interrupts enabled
> + * Max 256 pages
> + */
> +int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages)
> +{
> + struct page **pages;
> + int *counts;
> + int num_allocations;
> + int i, j, page_count;
> + int order;
> + int desired_order;
> + u16 status;
> + int ret;
> + u64 base_pfn;
> + struct hv_deposit_memory *input_page;
> + unsigned long flags;
> +
> + if (num_pages > HV_DEPOSIT_MAX)
> + return -E2BIG;
> + if (!num_pages)
> + return 0;
> +
> + /* One buffer for page pointers and counts */
> + pages = page_address(alloc_page(GFP_KERNEL));
> + if (!pages)
> + return -ENOMEM;
> +
> + counts = kcalloc(HV_DEPOSIT_MAX, sizeof(int), GFP_KERNEL);
> + if (!counts) {
> + free_page((unsigned long)pages);
> + return -ENOMEM;
> + }
> +
> + /* Allocate all the pages before disabling interrupts */
> + num_allocations = 0;
> + i = 0;
> + order = HV_DEPOSIT_MAX_ORDER;
> +
> + while (num_pages) {
> + /* Find highest order we can actually allocate */
> + desired_order = 31 - __builtin_clz(num_pages);
> + order = min(desired_order, order);
> + do {
> + pages[i] = alloc_pages_node(node, GFP_KERNEL, order);
> + if (!pages[i]) {
> + if (!order) {
> + ret = -ENOMEM;
> + goto err_free_allocations;
> + }
> + --order;
> + }
> + } while (!pages[i]);
> +
> + split_page(pages[i], order);
> + counts[i] = 1 << order;
> + num_pages -= counts[i];
> + i++;
> + num_allocations++;
> + }
> +
> + local_irq_save(flags);
> +
> + input_page = *this_cpu_ptr(hyperv_pcpu_input_arg);
> +
> + input_page->partition_id = partition_id;
> +
> + /* Populate gpa_page_list - these will fit on the input page */
> + for (i = 0, page_count = 0; i < num_allocations; ++i) {
> + base_pfn = page_to_pfn(pages[i]);
> + for (j = 0; j < counts[i]; ++j, ++page_count)
> + input_page->gpa_page_list[page_count] = base_pfn + j;
> + }
> + status = hv_do_rep_hypercall(HVCALL_DEPOSIT_MEMORY,
> + page_count, 0, input_page,
> + NULL) & HV_HYPERCALL_RESULT_MASK;
> + local_irq_restore(flags);
> +
> + if (status != HV_STATUS_SUCCESS) {
> + pr_err("Failed to deposit pages: %d\n", status);
> + ret = status;
> + goto err_free_allocations;
> + }
> +
> + ret = 0;
> + goto free_buf;
> +
> +err_free_allocations:
> + for (i = 0; i < num_allocations; ++i) {
> + base_pfn = page_to_pfn(pages[i]);
> + for (j = 0; j < counts[i]; ++j)
> + __free_page(pfn_to_page(base_pfn + j));
> + }
> +
> +free_buf:
> + free_page((unsigned long)pages);
> + kfree(counts);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(hv_call_deposit_pages);
> +
> +int hv_call_add_logical_proc(int node, u32 lp_index, u32 apic_id)
> +{
> + struct hv_add_logical_processor_in *input;
> + struct hv_add_logical_processor_out *output;
> + int status;
> + unsigned long flags;
> + int ret = 0;
> +
> + /*
> + * When adding a logical processor, the hypervisor may return
> + * HV_STATUS_INSUFFICIENT_MEMORY. When that happens, we deposit more
> + * pages and retry.
> + */
> + do {
> + local_irq_save(flags);
> +
> + input = *this_cpu_ptr(hyperv_pcpu_input_arg);
> + /* We don't do anything with the output right now */
> + output = *this_cpu_ptr(hyperv_pcpu_output_arg);
> +
> + input->lp_index = lp_index;
> + input->apic_id = apic_id;
> + input->flags = 0;
> + input->proximity_domain_info.domain_id = node_to_pxm(node);
> + input->proximity_domain_info.flags.reserved = 0;
> + input->proximity_domain_info.flags.proximity_info_valid = 1;
> + input->proximity_domain_info.flags.proximity_preferred = 1;
> + status = hv_do_hypercall(HVCALL_ADD_LOGICAL_PROCESSOR,
> + input, output);
> + local_irq_restore(flags);
> +
> + if (status != HV_STATUS_INSUFFICIENT_MEMORY) {
> + if (status != HV_STATUS_SUCCESS) {
> + pr_err("%s: cpu %u apic ID %u, %d\n", __func__,
> + lp_index, apic_id, status);
> + ret = status;
> + }
> + break;
> + }
> + ret = hv_call_deposit_pages(node, hv_current_partition_id, 1);
> + } while (!ret);
> +
> + return ret;
> +}
> +
> +int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags)
> +{
> + struct hv_create_vp *input;
> + u16 status;
> + unsigned long irq_flags;
> + int ret = 0;
> +
> + /* Root VPs don't seem to need pages deposited */
> + if (partition_id != hv_current_partition_id) {
> + ret = hv_call_deposit_pages(node, partition_id, 90);
> + if (ret)
> + return ret;
> + }
> +
> + do {
> + local_irq_save(irq_flags);
> +
> + input = *this_cpu_ptr(hyperv_pcpu_input_arg);
> +
> + input->partition_id = partition_id;
> + input->vp_index = vp_index;
> + input->flags = flags;
> + input->subnode_type = HvSubnodeAny;
> + if (node != NUMA_NO_NODE) {
> + input->proximity_domain_info.domain_id =
> node_to_pxm(node);
> + input->proximity_domain_info.flags.reserved = 0;
> + input->proximity_domain_info.flags.proximity_info_valid
> = 1;
> + input->proximity_domain_info.flags.proximity_preferred
> = 1;
> + } else {
> + input->proximity_domain_info.as_uint64 = 0;
> + }
> + status = hv_do_hypercall(HVCALL_CREATE_VP, input, NULL);
> + local_irq_restore(irq_flags);
> +
> + if (status != HV_STATUS_INSUFFICIENT_MEMORY) {
> + if (status != HV_STATUS_SUCCESS) {
> + pr_err("%s: vcpu %u, lp %u, %d\n", __func__,
> + vp_index, flags, status);
> + ret = status;
> + }
> + break;
> + }
> + ret = hv_call_deposit_pages(node, partition_id, 1);
> +
> + } while (!ret);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(hv_call_create_vp);
> +
> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> index 67f5d35a73d3..4e590a167160 100644
> --- a/arch/x86/include/asm/mshyperv.h
> +++ b/arch/x86/include/asm/mshyperv.h
> @@ -80,6 +80,10 @@ extern void __percpu **hyperv_pcpu_output_arg;
>
> extern u64 hv_current_partition_id;
>
> +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);
You seem to be only doing EXPORT_SYMBOL_GPL() for
hv_call_deposit_pages() and hv_call_create_vp() but not for
hv_call_add_logical_proc() - is this intended? Also, I don't see
hv_call_create_vp()/hv_call_add_logical_proc() usage outside of
arch/x86/kernel/cpu/mshyperv.c so maybe we don't need to export them at all?
> +
> 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 87b1a79b19eb..b6c74e1a5524 100644
> --- a/include/asm-generic/hyperv-tlfs.h
> +++ b/include/asm-generic/hyperv-tlfs.h
> @@ -142,6 +142,8 @@ struct ms_hyperv_tsc_page {
> #define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX 0x0014
> #define HVCALL_SEND_IPI_EX 0x0015
> #define HVCALL_GET_PARTITION_ID 0x0046
> +#define HVCALL_DEPOSIT_MEMORY 0x0048
> +#define HVCALL_CREATE_VP 0x004e
> #define HVCALL_GET_VP_REGISTERS 0x0050
> #define HVCALL_SET_VP_REGISTERS 0x0051
> #define HVCALL_POST_MESSAGE 0x005c
> @@ -149,6 +151,7 @@ struct ms_hyperv_tsc_page {
> #define HVCALL_POST_DEBUG_DATA 0x0069
> #define HVCALL_RETRIEVE_DEBUG_DATA 0x006a
> #define HVCALL_RESET_DEBUG_SESSION 0x006b
> +#define HVCALL_ADD_LOGICAL_PROCESSOR 0x0076
> #define HVCALL_RETARGET_INTERRUPT 0x007e
> #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE 0x00af
> #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST 0x00b0
> @@ -413,6 +416,70 @@ struct hv_get_partition_id {
> u64 partition_id;
> } __packed;
>
> +/* HvDepositMemory hypercall */
> +struct hv_deposit_memory {
> + u64 partition_id;
> + u64 gpa_page_list[];
> +} __packed;
> +
> +struct hv_proximity_domain_flags {
> + u32 proximity_preferred : 1;
> + u32 reserved : 30;
> + u32 proximity_info_valid : 1;
> +};
> +
> +/* Not a union in windows but useful for zeroing */
> +union hv_proximity_domain_info {
> + struct {
> + u32 domain_id;
> + struct hv_proximity_domain_flags flags;
> + };
> + u64 as_uint64;
> +};
> +
> +struct hv_lp_startup_status {
> + u64 hv_status;
> + u64 substatus1;
> + u64 substatus2;
> + u64 substatus3;
> + u64 substatus4;
> + u64 substatus5;
> + u64 substatus6;
> +};
> +
> +/* HvAddLogicalProcessor hypercall */
> +struct hv_add_logical_processor_in {
> + u32 lp_index;
> + u32 apic_id;
> + union hv_proximity_domain_info proximity_domain_info;
> + u64 flags;
> +};
> +
> +struct hv_add_logical_processor_out {
> + struct hv_lp_startup_status startup_status;
> +};
> +
> +enum HV_SUBNODE_TYPE
> +{
> + HvSubnodeAny = 0,
> + HvSubnodeSocket,
> + HvSubnodeAmdNode,
> + HvSubnodeL3,
> + HvSubnodeCount,
> + HvSubnodeInvalid = -1
> +};
> +
> +/* HvCreateVp hypercall */
> +struct hv_create_vp {
> + u64 partition_id;
> + u32 vp_index;
> + u8 padding[3];
> + u8 subnode_type;
> + u64 subnode_id;
> + union hv_proximity_domain_info proximity_domain_info;
> + u64 flags;
> +};
You add '__packed' to 'struct hv_deposit_memory' but not to 'struct
hv_create_vp'/'struct hv_add_logical_processor_in', this looks
inconsistent.
> +
> /* HvRetargetDeviceInterrupt hypercall */
> union hv_msi_entry {
> u64 as_uint64;
--
Vitaly
