arch/arm/xen/enlighten.c

   1 #include <xen/xen.h>
   2 #include <xen/events.h>
   3 #include <xen/grant_table.h>
   4 #include <xen/hvm.h>
   5 #include <xen/interface/vcpu.h>
   6 #include <xen/interface/xen.h>
   7 #include <xen/interface/memory.h>
   8 #include <xen/interface/hvm/params.h>
   9 #include <xen/features.h>
  10 #include <xen/platform_pci.h>
  11 #include <xen/xenbus.h>
  12 #include <xen/page.h>
  13 #include <xen/interface/sched.h>
  14 #include <xen/xen-ops.h>
  15 #include <asm/xen/hypervisor.h>
  16 #include <asm/xen/hypercall.h>
  17 #include <asm/system_misc.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/irqreturn.h>
  20 #include <linux/module.h>
  21 #include <linux/of.h>
  22 #include <linux/of_irq.h>
  23 #include <linux/of_address.h>
  24 #include <linux/cpuidle.h>
  25 #include <linux/cpufreq.h>
  26 #include <linux/cpu.h>
  27
  28 #include <linux/mm.h>
  29
  30 struct start_info _xen_start_info;
  31 struct start_info *xen_start_info = &_xen_start_info;
  32 EXPORT_SYMBOL_GPL(xen_start_info);
  33
  34 enum xen_domain_type xen_domain_type = XEN_NATIVE;
  35 EXPORT_SYMBOL_GPL(xen_domain_type);
  36
  37 struct shared_info xen_dummy_shared_info;
  38 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
  39
  40 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
  41 static struct vcpu_info __percpu *xen_vcpu_info;
  42
  43 /* These are unused until we support booting "pre-ballooned" */
  44 unsigned long xen_released_pages;
  45 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
  46
  47 /* TODO: to be removed */
  48 __read_mostly int xen_have_vector_callback;
  49 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
  50
  51 int xen_platform_pci_unplug = XEN_UNPLUG_ALL;
  52 EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
  53
  54 static __read_mostly int xen_events_irq = -1;
  55
  56 /* map fgmfn of domid to lpfn in the current domain */
  57 static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
  58                             unsigned int domid)
  59 {
  60         int rc;
  61         struct xen_add_to_physmap_range xatp = {
  62                 .domid = DOMID_SELF,
  63                 .foreign_domid = domid,
  64                 .size = 1,
  65                 .space = XENMAPSPACE_gmfn_foreign,
  66         };
  67         xen_ulong_t idx = fgmfn;
  68         xen_pfn_t gpfn = lpfn;
  69         int err = 0;
  70
  71         set_xen_guest_handle(xatp.idxs, &idx);
  72         set_xen_guest_handle(xatp.gpfns, &gpfn);
  73         set_xen_guest_handle(xatp.errs, &err);
  74
  75         rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
  76         if (rc || err) {
  77                 pr_warn("Failed to map pfn to mfn rc:%d:%d pfn:%lx mfn:%lx\n",
  78                         rc, err, lpfn, fgmfn);
  79                 return 1;
  80         }
  81         return 0;
  82 }
  83
  84 struct remap_data {
  85         xen_pfn_t fgmfn; /* foreign domain's gmfn */
  86         pgprot_t prot;
  87         domid_t  domid;
  88         struct vm_area_struct *vma;
  89         int index;
  90         struct page **pages;
  91         struct xen_remap_mfn_info *info;
  92 };
  93
  94 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
  95                         void *data)
  96 {
  97         struct remap_data *info = data;
  98         struct page *page = info->pages[info->index++];
  99         unsigned long pfn = page_to_pfn(page);
 100         pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot));
 101
 102         if (map_foreign_page(pfn, info->fgmfn, info->domid))
 103                 return -EFAULT;
 104         set_pte_at(info->vma->vm_mm, addr, ptep, pte);
 105
 106         return 0;
 107 }
 108
 109 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
 110                                unsigned long addr,
 111                                xen_pfn_t mfn, int nr,
 112                                pgprot_t prot, unsigned domid,
 113                                struct page **pages)
 114 {
 115         int err;
 116         struct remap_data data;
 117
 118         /* TBD: Batching, current sole caller only does page at a time */
 119         if (nr > 1)
 120                 return -EINVAL;
 121
 122         data.fgmfn = mfn;
 123         data.prot = prot;
 124         data.domid = domid;
 125         data.vma = vma;
 126         data.index = 0;
 127         data.pages = pages;
 128         err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
 129                                   remap_pte_fn, &data);
 130         return err;
 131 }
 132 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
 133
 134 int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
 135                                int nr, struct page **pages)
 136 {
 137         int i;
 138
 139         for (i = 0; i < nr; i++) {
 140                 struct xen_remove_from_physmap xrp;
 141                 unsigned long rc, pfn;
 142
 143                 pfn = page_to_pfn(pages[i]);
 144
 145                 xrp.domid = DOMID_SELF;
 146                 xrp.gpfn = pfn;
 147                 rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
 148                 if (rc) {
 149                         pr_warn("Failed to unmap pfn:%lx rc:%ld\n",
 150                                 pfn, rc);
 151                         return rc;
 152                 }
 153         }
 154         return 0;
 155 }
 156 EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
 157
 158 static void xen_percpu_init(void)
 159 {
 160         struct vcpu_register_vcpu_info info;
 161         struct vcpu_info *vcpup;
 162         int err;
 163         int cpu = get_cpu();
 164
 165         pr_info("Xen: initializing cpu%d\n", cpu);
 166         vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
 167
 168         info.mfn = __pa(vcpup) >> PAGE_SHIFT;
 169         info.offset = offset_in_page(vcpup);
 170
 171         err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
 172         BUG_ON(err);
 173         per_cpu(xen_vcpu, cpu) = vcpup;
 174
 175         enable_percpu_irq(xen_events_irq, 0);
 176         put_cpu();
 177 }
 178
 179 static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
 180 {
 181         struct sched_shutdown r = { .reason = SHUTDOWN_reboot };
 182         int rc;
 183         rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
 184         BUG_ON(rc);
 185 }
 186
 187 static void xen_power_off(void)
 188 {
 189         struct sched_shutdown r = { .reason = SHUTDOWN_poweroff };
 190         int rc;
 191         rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
 192         BUG_ON(rc);
 193 }
 194
 195 static int xen_cpu_notification(struct notifier_block *self,
 196                                 unsigned long action,
 197                                 void *hcpu)
 198 {
 199         switch (action) {
 200         case CPU_STARTING:
 201                 xen_percpu_init();
 202                 break;
 203         default:
 204                 break;
 205         }
 206
 207         return NOTIFY_OK;
 208 }
 209
 210 static struct notifier_block xen_cpu_notifier = {
 211         .notifier_call = xen_cpu_notification,
 212 };
 213
 214 static irqreturn_t xen_arm_callback(int irq, void *arg)
 215 {
 216         xen_hvm_evtchn_do_upcall();
 217         return IRQ_HANDLED;
 218 }
 219
 220 /*
 221  * see Documentation/devicetree/bindings/arm/xen.txt for the
 222  * documentation of the Xen Device Tree format.
 223  */
 224 #define GRANT_TABLE_PHYSADDR 0
 225 static int __init xen_guest_init(void)
 226 {
 227         struct xen_add_to_physmap xatp;
 228         static struct shared_info *shared_info_page = 0;
 229         struct device_node *node;
 230         int len;
 231         const char *s = NULL;
 232         const char *version = NULL;
 233         const char *xen_prefix = "xen,xen-";
 234         struct resource res;
 235         phys_addr_t grant_frames;
 236
 237         node = of_find_compatible_node(NULL, NULL, "xen,xen");
 238         if (!node) {
 239                 pr_debug("No Xen support\n");
 240                 return 0;
 241         }
 242         s = of_get_property(node, "compatible", &len);
 243         if (strlen(xen_prefix) + 3  < len &&
 244                         !strncmp(xen_prefix, s, strlen(xen_prefix)))
 245                 version = s + strlen(xen_prefix);
 246         if (version == NULL) {
 247                 pr_debug("Xen version not found\n");
 248                 return 0;
 249         }
 250         if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
 251                 return 0;
 252         grant_frames = res.start;
 253         xen_events_irq = irq_of_parse_and_map(node, 0);
 254         pr_info("Xen %s support found, events_irq=%d gnttab_frame=%pa\n",
 255                         version, xen_events_irq, &grant_frames);
 256
 257         if (xen_events_irq < 0)
 258                 return -ENODEV;
 259
 260         xen_domain_type = XEN_HVM_DOMAIN;
 261
 262         xen_setup_features();
 263
 264         if (xen_feature(XENFEAT_dom0))
 265                 xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
 266         else
 267                 xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
 268
 269         if (!shared_info_page)
 270                 shared_info_page = (struct shared_info *)
 271                         get_zeroed_page(GFP_KERNEL);
 272         if (!shared_info_page) {
 273                 pr_err("not enough memory\n");
 274                 return -ENOMEM;
 275         }
 276         xatp.domid = DOMID_SELF;
 277         xatp.idx = 0;
 278         xatp.space = XENMAPSPACE_shared_info;
 279         xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
 280         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
 281                 BUG();
 282
 283         HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
 284
 285         /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
 286          * page, we use it in the event channel upcall and in some pvclock
 287          * related functions.
 288          * The shared info contains exactly 1 CPU (the boot CPU). The guest
 289          * is required to use VCPUOP_register_vcpu_info to place vcpu info
 290          * for secondary CPUs as they are brought up.
 291          * For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
 292          */
 293         xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info),
 294                                                sizeof(struct vcpu_info));
 295         if (xen_vcpu_info == NULL)
 296                 return -ENOMEM;
 297
 298         if (gnttab_setup_auto_xlat_frames(grant_frames)) {
 299                 free_percpu(xen_vcpu_info);
 300                 return -ENOMEM;
 301         }
 302         gnttab_init();
 303         if (!xen_initial_domain())
 304                 xenbus_probe(NULL);
 305
 306         /*
 307          * Making sure board specific code will not set up ops for
 308          * cpu idle and cpu freq.
 309          */
 310         disable_cpuidle();
 311         disable_cpufreq();
 312
 313         xen_init_IRQ();
 314
 315         if (request_percpu_irq(xen_events_irq, xen_arm_callback,
 316                                "events", &xen_vcpu)) {
 317                 pr_err("Error request IRQ %d\n", xen_events_irq);
 318                 return -EINVAL;
 319         }
 320
 321         xen_percpu_init();
 322
 323         register_cpu_notifier(&xen_cpu_notifier);
 324
 325         return 0;
 326 }
 327 early_initcall(xen_guest_init);
 328
 329 static int __init xen_pm_init(void)
 330 {
 331         if (!xen_domain())
 332                 return -ENODEV;
 333
 334         pm_power_off = xen_power_off;
 335         arm_pm_restart = xen_restart;
 336
 337         return 0;
 338 }
 339 late_initcall(xen_pm_init);
 340
 341
 342 /* empty stubs */
 343 void xen_arch_pre_suspend(void) { }
 344 void xen_arch_post_suspend(int suspend_cancelled) { }
 345 void xen_timer_resume(void) { }
 346 void xen_arch_resume(void) { }
 347
 348
 349 /* In the hypervisor.S file. */
 350 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
 351 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
 352 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
 353 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
 354 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
 355 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
 356 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
 357 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
 358 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
 359 EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
 360 EXPORT_SYMBOL_GPL(HYPERVISOR_multicall);
 361 EXPORT_SYMBOL_GPL(privcmd_call);