cpu: Make first_cpu and next_cpu CPUState

Move next_cpu from CPU_COMMON to CPUState.
Move first_cpu variable to qom/cpu.h.

gdbstub needs to use CPUState::env_ptr for now.
cpu_copy() no longer needs to save and restore cpu_next.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
[AF: Rebased, simplified cpu_copy()]
Signed-off-by: Andreas Färber <afaerber@suse.de>
diff --git a/target-i386/arch_dump.c b/target-i386/arch_dump.c
index 83898cd..d133228 100644
--- a/target-i386/arch_dump.c
+++ b/target-i386/arch_dump.c
@@ -185,7 +185,8 @@
     X86CPU *cpu = X86_CPU(cs);
     int ret;
 #ifdef TARGET_X86_64
-    bool lma = !!(first_cpu->hflags & HF_LMA_MASK);
+    X86CPU *first_x86_cpu = X86_CPU(first_cpu);
+    bool lma = !!(first_x86_cpu->env.hflags & HF_LMA_MASK);
 
     if (lma) {
         ret = x86_64_write_elf64_note(f, &cpu->env, cpuid, opaque);
@@ -394,7 +395,9 @@
     RAMBlock *block;
 
 #ifdef TARGET_X86_64
-    lma = !!(first_cpu->hflags & HF_LMA_MASK);
+    X86CPU *first_x86_cpu = X86_CPU(first_cpu);
+
+    lma = !!(first_x86_cpu->env.hflags & HF_LMA_MASK);
 #endif
 
     if (lma) {
diff --git a/target-i386/helper.c b/target-i386/helper.c
index 5e5abe3..d6f43d7 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -1188,6 +1188,7 @@
                         uint64_t status, uint64_t mcg_status, uint64_t addr,
                         uint64_t misc, int flags)
 {
+    CPUState *cs = CPU(cpu);
     CPUX86State *cenv = &cpu->env;
     MCEInjectionParams params = {
         .mon = mon,
@@ -1200,7 +1201,6 @@
         .flags = flags,
     };
     unsigned bank_num = cenv->mcg_cap & 0xff;
-    CPUX86State *env;
 
     if (!cenv->mcg_cap) {
         monitor_printf(mon, "MCE injection not supported\n");
@@ -1220,19 +1220,22 @@
         return;
     }
 
-    run_on_cpu(CPU(cpu), do_inject_x86_mce, &params);
+    run_on_cpu(cs, do_inject_x86_mce, &params);
     if (flags & MCE_INJECT_BROADCAST) {
+        CPUState *other_cs;
+
         params.bank = 1;
         params.status = MCI_STATUS_VAL | MCI_STATUS_UC;
         params.mcg_status = MCG_STATUS_MCIP | MCG_STATUS_RIPV;
         params.addr = 0;
         params.misc = 0;
-        for (env = first_cpu; env != NULL; env = env->next_cpu) {
-            if (cenv == env) {
+        for (other_cs = first_cpu; other_cs != NULL;
+             other_cs = other_cs->next_cpu) {
+            if (other_cs == cs) {
                 continue;
             }
-            params.cpu = x86_env_get_cpu(env);
-            run_on_cpu(CPU(cpu), do_inject_x86_mce, &params);
+            params.cpu = X86_CPU(other_cs);
+            run_on_cpu(other_cs, do_inject_x86_mce, &params);
         }
     }
 }
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 4b557b3..935ef63 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -345,20 +345,22 @@
 
 int kvm_arch_on_sigbus(int code, void *addr)
 {
-    if ((first_cpu->mcg_cap & MCG_SER_P) && addr && code == BUS_MCEERR_AO) {
+    X86CPU *cpu = X86_CPU(first_cpu);
+
+    if ((cpu->env.mcg_cap & MCG_SER_P) && addr && code == BUS_MCEERR_AO) {
         ram_addr_t ram_addr;
         hwaddr paddr;
 
         /* Hope we are lucky for AO MCE */
         if (qemu_ram_addr_from_host(addr, &ram_addr) == NULL ||
-            !kvm_physical_memory_addr_from_host(CPU(first_cpu)->kvm_state,
+            !kvm_physical_memory_addr_from_host(first_cpu->kvm_state,
                                                 addr, &paddr)) {
             fprintf(stderr, "Hardware memory error for memory used by "
                     "QEMU itself instead of guest system!: %p\n", addr);
             return 0;
         }
         kvm_hwpoison_page_add(ram_addr);
-        kvm_mce_inject(x86_env_get_cpu(first_cpu), paddr, code);
+        kvm_mce_inject(X86_CPU(first_cpu), paddr, code);
     } else {
         if (code == BUS_MCEERR_AO) {
             return 0;
diff --git a/target-i386/misc_helper.c b/target-i386/misc_helper.c
index e345f9a..957926c 100644
--- a/target-i386/misc_helper.c
+++ b/target-i386/misc_helper.c
@@ -610,7 +610,7 @@
     cpu = x86_env_get_cpu(env);
     cs = CPU(cpu);
     /* XXX: not complete but not completely erroneous */
-    if (cs->cpu_index != 0 || env->next_cpu != NULL) {
+    if (cs->cpu_index != 0 || cs->next_cpu != NULL) {
         /* more than one CPU: do not sleep because another CPU may
            wake this one */
     } else {