1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/types.h> 3 #include <linux/vmalloc.h> 4 #include <linux/mm.h> 5 #include <linux/clockchips.h> 6 #include <linux/slab.h> 7 #include <linux/cpuhotplug.h> 8 #include <linux/minmax.h> 9 #include <asm/mshyperv.h> 10 11 /* 12 * See struct hv_deposit_memory. The first u64 is partition ID, the rest 13 * are GPAs. 14 */ 15 #define HV_DEPOSIT_MAX (HV_HYP_PAGE_SIZE / sizeof(u64) - 1) 16 17 /* Deposits exact number of pages. Must be called with interrupts enabled. */ 18 int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages) 19 { 20 struct page **pages, *page; 21 int *counts; 22 int num_allocations; 23 int i, j, page_count; 24 int order; 25 u64 status; 26 int ret; 27 u64 base_pfn; 28 struct hv_deposit_memory *input_page; 29 unsigned long flags; 30 31 if (num_pages > HV_DEPOSIT_MAX) 32 return -E2BIG; 33 if (!num_pages) 34 return 0; 35 36 /* One buffer for page pointers and counts */ 37 page = alloc_page(GFP_KERNEL); 38 if (!page) 39 return -ENOMEM; 40 pages = page_address(page); 41 42 counts = kcalloc(HV_DEPOSIT_MAX, sizeof(int), GFP_KERNEL); 43 if (!counts) { 44 free_page((unsigned long)pages); 45 return -ENOMEM; 46 } 47 48 /* Allocate all the pages before disabling interrupts */ 49 i = 0; 50 51 while (num_pages) { 52 /* Find highest order we can actually allocate */ 53 order = 31 - __builtin_clz(num_pages); 54 55 while (1) { 56 pages[i] = alloc_pages_node(node, GFP_KERNEL, order); 57 if (pages[i]) 58 break; 59 if (!order) { 60 ret = -ENOMEM; 61 num_allocations = i; 62 goto err_free_allocations; 63 } 64 --order; 65 } 66 67 split_page(pages[i], order); 68 counts[i] = 1 << order; 69 num_pages -= counts[i]; 70 i++; 71 } 72 num_allocations = i; 73 74 local_irq_save(flags); 75 76 input_page = *this_cpu_ptr(hyperv_pcpu_input_arg); 77 78 input_page->partition_id = partition_id; 79 80 /* Populate gpa_page_list - these will fit on the input page */ 81 for (i = 0, page_count = 0; i < num_allocations; ++i) { 82 base_pfn = page_to_pfn(pages[i]); 83 for (j = 0; j < counts[i]; ++j, ++page_count) 84 input_page->gpa_page_list[page_count] = base_pfn + j; 85 } 86 status = hv_do_rep_hypercall(HVCALL_DEPOSIT_MEMORY, 87 page_count, 0, input_page, NULL); 88 local_irq_restore(flags); 89 if (!hv_result_success(status)) { 90 hv_status_err(status, "\n"); 91 ret = hv_result_to_errno(status); 92 goto err_free_allocations; 93 } 94 95 ret = 0; 96 goto free_buf; 97 98 err_free_allocations: 99 for (i = 0; i < num_allocations; ++i) { 100 base_pfn = page_to_pfn(pages[i]); 101 for (j = 0; j < counts[i]; ++j) 102 __free_page(pfn_to_page(base_pfn + j)); 103 } 104 105 free_buf: 106 free_page((unsigned long)pages); 107 kfree(counts); 108 return ret; 109 } 110 111 int hv_call_add_logical_proc(int node, u32 lp_index, u32 apic_id) 112 { 113 struct hv_input_add_logical_processor *input; 114 struct hv_output_add_logical_processor *output; 115 u64 status; 116 unsigned long flags; 117 int ret = 0; 118 119 /* 120 * When adding a logical processor, the hypervisor may return 121 * HV_STATUS_INSUFFICIENT_MEMORY. When that happens, we deposit more 122 * pages and retry. 123 */ 124 do { 125 local_irq_save(flags); 126 127 input = *this_cpu_ptr(hyperv_pcpu_input_arg); 128 /* We don't do anything with the output right now */ 129 output = *this_cpu_ptr(hyperv_pcpu_output_arg); 130 131 input->lp_index = lp_index; 132 input->apic_id = apic_id; 133 input->proximity_domain_info = hv_numa_node_to_pxm_info(node); 134 status = hv_do_hypercall(HVCALL_ADD_LOGICAL_PROCESSOR, 135 input, output); 136 local_irq_restore(flags); 137 138 if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) { 139 if (!hv_result_success(status)) { 140 hv_status_err(status, "cpu %u apic ID: %u\n", 141 lp_index, apic_id); 142 ret = hv_result_to_errno(status); 143 } 144 break; 145 } 146 ret = hv_call_deposit_pages(node, hv_current_partition_id, 1); 147 } while (!ret); 148 149 return ret; 150 } 151 152 int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags) 153 { 154 struct hv_create_vp *input; 155 u64 status; 156 unsigned long irq_flags; 157 int ret = 0; 158 159 /* Root VPs don't seem to need pages deposited */ 160 if (partition_id != hv_current_partition_id) { 161 /* The value 90 is empirically determined. It may change. */ 162 ret = hv_call_deposit_pages(node, partition_id, 90); 163 if (ret) 164 return ret; 165 } 166 167 do { 168 local_irq_save(irq_flags); 169 170 input = *this_cpu_ptr(hyperv_pcpu_input_arg); 171 172 input->partition_id = partition_id; 173 input->vp_index = vp_index; 174 input->flags = flags; 175 input->subnode_type = HV_SUBNODE_ANY; 176 input->proximity_domain_info = hv_numa_node_to_pxm_info(node); 177 status = hv_do_hypercall(HVCALL_CREATE_VP, input, NULL); 178 local_irq_restore(irq_flags); 179 180 if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) { 181 if (!hv_result_success(status)) { 182 hv_status_err(status, "vcpu: %u, lp: %u\n", 183 vp_index, flags); 184 ret = hv_result_to_errno(status); 185 } 186 break; 187 } 188 ret = hv_call_deposit_pages(node, partition_id, 1); 189 190 } while (!ret); 191 192 return ret; 193 } 194 195