x86/hyperv: Move the code in ivm.c around to avoid unnecessary ifdef's

Group the code this way so that we can avoid too many ifdef's:

  Data only used in an SNP VM with the paravisor;
  Functions only used in an SNP VM with the paravisor;

  Data only used in an SNP VM without the paravisor;
  Functions only used in an SNP VM without the paravisor;

  Functions only used in a TDX VM, with and without the paravisor;

  Functions used in an SNP or TDX VM, when the paravisor is present;

  Functions always used, even in a regular non-CoCo VM.

No functional change.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20230824080712.30327-11-decui@microsoft.com

diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c
index 3d48f82..8fb3b28 100644 (file)
--- a/arch/x86/hyperv/ivm.c
+++ b/arch/x86/hyperv/ivm.c
@@ -30,9 +30,6 @@
 
 #define GHCB_USAGE_HYPERV_CALL 1
 
-static u8 ap_start_input_arg[PAGE_SIZE] __bss_decrypted __aligned(PAGE_SIZE);
-static u8 ap_start_stack[PAGE_SIZE] __aligned(PAGE_SIZE);
-
 union hv_ghcb {
        struct ghcb ghcb;
        struct {
@@ -66,10 +63,10 @@ union hv_ghcb {
        } hypercall;
 } __packed __aligned(HV_HYP_PAGE_SIZE);
 
-static DEFINE_PER_CPU(struct sev_es_save_area *, hv_sev_vmsa);
-
+/* Only used in an SNP VM with the paravisor */
 static u16 hv_ghcb_version __ro_after_init;
 
+/* Functions only used in an SNP VM with the paravisor go here. */
 u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size)
 {
        union hv_ghcb *hv_ghcb;
@@ -247,6 +244,140 @@ static void hv_ghcb_msr_read(u64 msr, u64 *value)
        local_irq_restore(flags);
 }
 
+/* Only used in a fully enlightened SNP VM, i.e. without the paravisor */
+static u8 ap_start_input_arg[PAGE_SIZE] __bss_decrypted __aligned(PAGE_SIZE);
+static u8 ap_start_stack[PAGE_SIZE] __aligned(PAGE_SIZE);
+static DEFINE_PER_CPU(struct sev_es_save_area *, hv_sev_vmsa);
+
+/* Functions only used in an SNP VM without the paravisor go here. */
+
+#define hv_populate_vmcb_seg(seg, gdtr_base)                   \
+do {                                                           \
+       if (seg.selector) {                                     \
+               seg.base = 0;                                   \
+               seg.limit = HV_AP_SEGMENT_LIMIT;                \
+               seg.attrib = *(u16 *)(gdtr_base + seg.selector + 5);    \
+               seg.attrib = (seg.attrib & 0xFF) | ((seg.attrib >> 4) & 0xF00); \
+       }                                                       \
+} while (0)                                                    \
+
+static int snp_set_vmsa(void *va, bool vmsa)
+{
+       u64 attrs;
+
+       /*
+        * Running at VMPL0 allows the kernel to change the VMSA bit for a page
+        * using the RMPADJUST instruction. However, for the instruction to
+        * succeed it must target the permissions of a lesser privileged
+        * (higher numbered) VMPL level, so use VMPL1 (refer to the RMPADJUST
+        * instruction in the AMD64 APM Volume 3).
+        */
+       attrs = 1;
+       if (vmsa)
+               attrs |= RMPADJUST_VMSA_PAGE_BIT;
+
+       return rmpadjust((unsigned long)va, RMP_PG_SIZE_4K, attrs);
+}
+
+static void snp_cleanup_vmsa(struct sev_es_save_area *vmsa)
+{
+       int err;
+
+       err = snp_set_vmsa(vmsa, false);
+       if (err)
+               pr_err("clear VMSA page failed (%u), leaking page\n", err);
+       else
+               free_page((unsigned long)vmsa);
+}
+
+int hv_snp_boot_ap(int cpu, unsigned long start_ip)
+{
+       struct sev_es_save_area *vmsa = (struct sev_es_save_area *)
+               __get_free_page(GFP_KERNEL | __GFP_ZERO);
+       struct sev_es_save_area *cur_vmsa;
+       struct desc_ptr gdtr;
+       u64 ret, retry = 5;
+       struct hv_enable_vp_vtl *start_vp_input;
+       unsigned long flags;
+
+       if (!vmsa)
+               return -ENOMEM;
+
+       native_store_gdt(&gdtr);
+
+       vmsa->gdtr.base = gdtr.address;
+       vmsa->gdtr.limit = gdtr.size;
+
+       asm volatile("movl %%es, %%eax;" : "=a" (vmsa->es.selector));
+       hv_populate_vmcb_seg(vmsa->es, vmsa->gdtr.base);
+
+       asm volatile("movl %%cs, %%eax;" : "=a" (vmsa->cs.selector));
+       hv_populate_vmcb_seg(vmsa->cs, vmsa->gdtr.base);
+
+       asm volatile("movl %%ss, %%eax;" : "=a" (vmsa->ss.selector));
+       hv_populate_vmcb_seg(vmsa->ss, vmsa->gdtr.base);
+
+       asm volatile("movl %%ds, %%eax;" : "=a" (vmsa->ds.selector));
+       hv_populate_vmcb_seg(vmsa->ds, vmsa->gdtr.base);
+
+       vmsa->efer = native_read_msr(MSR_EFER);
+
+       asm volatile("movq %%cr4, %%rax;" : "=a" (vmsa->cr4));
+       asm volatile("movq %%cr3, %%rax;" : "=a" (vmsa->cr3));
+       asm volatile("movq %%cr0, %%rax;" : "=a" (vmsa->cr0));
+
+       vmsa->xcr0 = 1;
+       vmsa->g_pat = HV_AP_INIT_GPAT_DEFAULT;
+       vmsa->rip = (u64)secondary_startup_64_no_verify;
+       vmsa->rsp = (u64)&ap_start_stack[PAGE_SIZE];
+
+       /*
+        * Set the SNP-specific fields for this VMSA:
+        *   VMPL level
+        *   SEV_FEATURES (matches the SEV STATUS MSR right shifted 2 bits)
+        */
+       vmsa->vmpl = 0;
+       vmsa->sev_features = sev_status >> 2;
+
+       ret = snp_set_vmsa(vmsa, true);
+       if (!ret) {
+               pr_err("RMPADJUST(%llx) failed: %llx\n", (u64)vmsa, ret);
+               free_page((u64)vmsa);
+               return ret;
+       }
+
+       local_irq_save(flags);
+       start_vp_input = (struct hv_enable_vp_vtl *)ap_start_input_arg;
+       memset(start_vp_input, 0, sizeof(*start_vp_input));
+       start_vp_input->partition_id = -1;
+       start_vp_input->vp_index = cpu;
+       start_vp_input->target_vtl.target_vtl = ms_hyperv.vtl;
+       *(u64 *)&start_vp_input->vp_context = __pa(vmsa) | 1;
+
+       do {
+               ret = hv_do_hypercall(HVCALL_START_VP,
+                                     start_vp_input, NULL);
+       } while (hv_result(ret) == HV_STATUS_TIME_OUT && retry--);
+
+       local_irq_restore(flags);
+
+       if (!hv_result_success(ret)) {
+               pr_err("HvCallStartVirtualProcessor failed: %llx\n", ret);
+               snp_cleanup_vmsa(vmsa);
+               vmsa = NULL;
+       }
+
+       cur_vmsa = per_cpu(hv_sev_vmsa, cpu);
+       /* Free up any previous VMSA page */
+       if (cur_vmsa)
+               snp_cleanup_vmsa(cur_vmsa);
+
+       /* Record the current VMSA page */
+       per_cpu(hv_sev_vmsa, cpu) = vmsa;
+
+       return ret;
+}
+
 #else
 static inline void hv_ghcb_msr_write(u64 msr, u64 value) {}
 static inline void hv_ghcb_msr_read(u64 msr, u64 *value) {}
@@ -282,6 +413,20 @@ static void hv_tdx_msr_read(u64 msr, u64 *val)
        else
                *val = args.r11;
 }
+
+u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2)
+{
+       struct tdx_hypercall_args args = { };
+
+       args.r10 = control;
+       args.rdx = param1;
+       args.r8  = param2;
+
+       (void)__tdx_hypercall_ret(&args);
+
+       return args.r11;
+}
+
 #else
 static inline void hv_tdx_msr_write(u64 msr, u64 value) {}
 static inline void hv_tdx_msr_read(u64 msr, u64 *value) {}
@@ -309,9 +454,7 @@ void hv_ivm_msr_read(u64 msr, u64 *value)
        else if (hv_isolation_type_snp())
                hv_ghcb_msr_read(msr, value);
 }
-#endif
 
-#if defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST)
 /*
  * hv_mark_gpa_visibility - Set pages visible to host via hvcall.
  *
@@ -432,141 +575,6 @@ static bool hv_is_private_mmio(u64 addr)
        return false;
 }
 
-#endif /* defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST) */
-
-#ifdef CONFIG_AMD_MEM_ENCRYPT
-
-#define hv_populate_vmcb_seg(seg, gdtr_base)                   \
-do {                                                           \
-       if (seg.selector) {                                     \
-               seg.base = 0;                                   \
-               seg.limit = HV_AP_SEGMENT_LIMIT;                \
-               seg.attrib = *(u16 *)(gdtr_base + seg.selector + 5);    \
-               seg.attrib = (seg.attrib & 0xFF) | ((seg.attrib >> 4) & 0xF00); \
-       }                                                       \
-} while (0)                                                    \
-
-static int snp_set_vmsa(void *va, bool vmsa)
-{
-       u64 attrs;
-
-       /*
-        * Running at VMPL0 allows the kernel to change the VMSA bit for a page
-        * using the RMPADJUST instruction. However, for the instruction to
-        * succeed it must target the permissions of a lesser privileged
-        * (higher numbered) VMPL level, so use VMPL1 (refer to the RMPADJUST
-        * instruction in the AMD64 APM Volume 3).
-        */
-       attrs = 1;
-       if (vmsa)
-               attrs |= RMPADJUST_VMSA_PAGE_BIT;
-
-       return rmpadjust((unsigned long)va, RMP_PG_SIZE_4K, attrs);
-}
-
-static void snp_cleanup_vmsa(struct sev_es_save_area *vmsa)
-{
-       int err;
-
-       err = snp_set_vmsa(vmsa, false);
-       if (err)
-               pr_err("clear VMSA page failed (%u), leaking page\n", err);
-       else
-               free_page((unsigned long)vmsa);
-}
-
-int hv_snp_boot_ap(int cpu, unsigned long start_ip)
-{
-       struct sev_es_save_area *vmsa = (struct sev_es_save_area *)
-               __get_free_page(GFP_KERNEL | __GFP_ZERO);
-       struct sev_es_save_area *cur_vmsa;
-       struct desc_ptr gdtr;
-       u64 ret, retry = 5;
-       struct hv_enable_vp_vtl *start_vp_input;
-       unsigned long flags;
-
-       if (!vmsa)
-               return -ENOMEM;
-
-       native_store_gdt(&gdtr);
-
-       vmsa->gdtr.base = gdtr.address;
-       vmsa->gdtr.limit = gdtr.size;
-
-       asm volatile("movl %%es, %%eax;" : "=a" (vmsa->es.selector));
-       hv_populate_vmcb_seg(vmsa->es, vmsa->gdtr.base);
-
-       asm volatile("movl %%cs, %%eax;" : "=a" (vmsa->cs.selector));
-       hv_populate_vmcb_seg(vmsa->cs, vmsa->gdtr.base);
-
-       asm volatile("movl %%ss, %%eax;" : "=a" (vmsa->ss.selector));
-       hv_populate_vmcb_seg(vmsa->ss, vmsa->gdtr.base);
-
-       asm volatile("movl %%ds, %%eax;" : "=a" (vmsa->ds.selector));
-       hv_populate_vmcb_seg(vmsa->ds, vmsa->gdtr.base);
-
-       vmsa->efer = native_read_msr(MSR_EFER);
-
-       asm volatile("movq %%cr4, %%rax;" : "=a" (vmsa->cr4));
-       asm volatile("movq %%cr3, %%rax;" : "=a" (vmsa->cr3));
-       asm volatile("movq %%cr0, %%rax;" : "=a" (vmsa->cr0));
-
-       vmsa->xcr0 = 1;
-       vmsa->g_pat = HV_AP_INIT_GPAT_DEFAULT;
-       vmsa->rip = (u64)secondary_startup_64_no_verify;
-       vmsa->rsp = (u64)&ap_start_stack[PAGE_SIZE];
-
-       /*
-        * Set the SNP-specific fields for this VMSA:
-        *   VMPL level
-        *   SEV_FEATURES (matches the SEV STATUS MSR right shifted 2 bits)
-        */
-       vmsa->vmpl = 0;
-       vmsa->sev_features = sev_status >> 2;
-
-       ret = snp_set_vmsa(vmsa, true);
-       if (!ret) {
-               pr_err("RMPADJUST(%llx) failed: %llx\n", (u64)vmsa, ret);
-               free_page((u64)vmsa);
-               return ret;
-       }
-
-       local_irq_save(flags);
-       start_vp_input = (struct hv_enable_vp_vtl *)ap_start_input_arg;
-       memset(start_vp_input, 0, sizeof(*start_vp_input));
-       start_vp_input->partition_id = -1;
-       start_vp_input->vp_index = cpu;
-       start_vp_input->target_vtl.target_vtl = ms_hyperv.vtl;
-       *(u64 *)&start_vp_input->vp_context = __pa(vmsa) | 1;
-
-       do {
-               ret = hv_do_hypercall(HVCALL_START_VP,
-                                     start_vp_input, NULL);
-       } while (hv_result(ret) == HV_STATUS_TIME_OUT && retry--);
-
-       local_irq_restore(flags);
-
-       if (!hv_result_success(ret)) {
-               pr_err("HvCallStartVirtualProcessor failed: %llx\n", ret);
-               snp_cleanup_vmsa(vmsa);
-               vmsa = NULL;
-       }
-
-       cur_vmsa = per_cpu(hv_sev_vmsa, cpu);
-       /* Free up any previous VMSA page */
-       if (cur_vmsa)
-               snp_cleanup_vmsa(cur_vmsa);
-
-       /* Record the current VMSA page */
-       per_cpu(hv_sev_vmsa, cpu) = vmsa;
-
-       return ret;
-}
-
-#endif /* CONFIG_AMD_MEM_ENCRYPT */
-
-#if defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST)
-
 void __init hv_vtom_init(void)
 {
        enum hv_isolation_type type = hv_get_isolation_type();
@@ -654,20 +662,3 @@ bool hv_isolation_type_tdx(void)
 {
        return static_branch_unlikely(&isolation_type_tdx);
 }
-
-#ifdef CONFIG_INTEL_TDX_GUEST
-
-u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2)
-{
-       struct tdx_hypercall_args args = { };
-
-       args.r10 = control;
-       args.rdx = param1;
-       args.r8  = param2;
-
-       (void)__tdx_hypercall_ret(&args);
-
-       return args.r11;
-}
-
-#endif