| /* |
| * Machine specific setup for xen |
| * |
| * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/sched.h> |
| #include <linux/mm.h> |
| #include <linux/pm.h> |
| #include <linux/memblock.h> |
| #include <linux/cpuidle.h> |
| #include <linux/cpufreq.h> |
| |
| #include <asm/elf.h> |
| #include <asm/vdso.h> |
| #include <asm/e820.h> |
| #include <asm/setup.h> |
| #include <asm/acpi.h> |
| #include <asm/xen/hypervisor.h> |
| #include <asm/xen/hypercall.h> |
| |
| #include <xen/xen.h> |
| #include <xen/page.h> |
| #include <xen/interface/callback.h> |
| #include <xen/interface/memory.h> |
| #include <xen/interface/physdev.h> |
| #include <xen/features.h> |
| #include "xen-ops.h" |
| #include "vdso.h" |
| |
| /* These are code, but not functions. Defined in entry.S */ |
| extern const char xen_hypervisor_callback[]; |
| extern const char xen_failsafe_callback[]; |
| extern void xen_sysenter_target(void); |
| extern void xen_syscall_target(void); |
| extern void xen_syscall32_target(void); |
| |
| /* Amount of extra memory space we add to the e820 ranges */ |
| struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; |
| |
| /* Number of pages released from the initial allocation. */ |
| unsigned long xen_released_pages; |
| |
| /* |
| * The maximum amount of extra memory compared to the base size. The |
| * main scaling factor is the size of struct page. At extreme ratios |
| * of base:extra, all the base memory can be filled with page |
| * structures for the extra memory, leaving no space for anything |
| * else. |
| * |
| * 10x seems like a reasonable balance between scaling flexibility and |
| * leaving a practically usable system. |
| */ |
| #define EXTRA_MEM_RATIO (10) |
| |
| static void __init xen_add_extra_mem(u64 start, u64 size) |
| { |
| unsigned long pfn; |
| int i; |
| |
| for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { |
| /* Add new region. */ |
| if (xen_extra_mem[i].size == 0) { |
| xen_extra_mem[i].start = start; |
| xen_extra_mem[i].size = size; |
| break; |
| } |
| /* Append to existing region. */ |
| if (xen_extra_mem[i].start + xen_extra_mem[i].size == start) { |
| xen_extra_mem[i].size += size; |
| break; |
| } |
| } |
| if (i == XEN_EXTRA_MEM_MAX_REGIONS) |
| printk(KERN_WARNING "Warning: not enough extra memory regions\n"); |
| |
| memblock_reserve(start, size); |
| |
| xen_max_p2m_pfn = PFN_DOWN(start + size); |
| for (pfn = PFN_DOWN(start); pfn < xen_max_p2m_pfn; pfn++) { |
| unsigned long mfn = pfn_to_mfn(pfn); |
| |
| if (WARN(mfn == pfn, "Trying to over-write 1-1 mapping (pfn: %lx)\n", pfn)) |
| continue; |
| WARN(mfn != INVALID_P2M_ENTRY, "Trying to remove %lx which has %lx mfn!\n", |
| pfn, mfn); |
| |
| __set_phys_to_machine(pfn, INVALID_P2M_ENTRY); |
| } |
| } |
| |
| static unsigned long __init xen_do_chunk(unsigned long start, |
| unsigned long end, bool release) |
| { |
| struct xen_memory_reservation reservation = { |
| .address_bits = 0, |
| .extent_order = 0, |
| .domid = DOMID_SELF |
| }; |
| unsigned long len = 0; |
| unsigned long pfn; |
| int ret; |
| |
| for (pfn = start; pfn < end; pfn++) { |
| unsigned long frame; |
| unsigned long mfn = pfn_to_mfn(pfn); |
| |
| if (release) { |
| /* Make sure pfn exists to start with */ |
| if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn) |
| continue; |
| frame = mfn; |
| } else { |
| if (mfn != INVALID_P2M_ENTRY) |
| continue; |
| frame = pfn; |
| } |
| set_xen_guest_handle(reservation.extent_start, &frame); |
| reservation.nr_extents = 1; |
| |
| ret = HYPERVISOR_memory_op(release ? XENMEM_decrease_reservation : XENMEM_populate_physmap, |
| &reservation); |
| WARN(ret != 1, "Failed to %s pfn %lx err=%d\n", |
| release ? "release" : "populate", pfn, ret); |
| |
| if (ret == 1) { |
| if (!early_set_phys_to_machine(pfn, release ? INVALID_P2M_ENTRY : frame)) { |
| if (release) |
| break; |
| set_xen_guest_handle(reservation.extent_start, &frame); |
| reservation.nr_extents = 1; |
| ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, |
| &reservation); |
| break; |
| } |
| len++; |
| } else |
| break; |
| } |
| if (len) |
| printk(KERN_INFO "%s %lx-%lx pfn range: %lu pages %s\n", |
| release ? "Freeing" : "Populating", |
| start, end, len, |
| release ? "freed" : "added"); |
| |
| return len; |
| } |
| |
| static unsigned long __init xen_release_chunk(unsigned long start, |
| unsigned long end) |
| { |
| return xen_do_chunk(start, end, true); |
| } |
| |
| static unsigned long __init xen_populate_chunk( |
| const struct e820entry *list, size_t map_size, |
| unsigned long max_pfn, unsigned long *last_pfn, |
| unsigned long credits_left) |
| { |
| const struct e820entry *entry; |
| unsigned int i; |
| unsigned long done = 0; |
| unsigned long dest_pfn; |
| |
| for (i = 0, entry = list; i < map_size; i++, entry++) { |
| unsigned long s_pfn; |
| unsigned long e_pfn; |
| unsigned long pfns; |
| long capacity; |
| |
| if (credits_left <= 0) |
| break; |
| |
| if (entry->type != E820_RAM) |
| continue; |
| |
| e_pfn = PFN_DOWN(entry->addr + entry->size); |
| |
| /* We only care about E820 after the xen_start_info->nr_pages */ |
| if (e_pfn <= max_pfn) |
| continue; |
| |
| s_pfn = PFN_UP(entry->addr); |
| /* If the E820 falls within the nr_pages, we want to start |
| * at the nr_pages PFN. |
| * If that would mean going past the E820 entry, skip it |
| */ |
| if (s_pfn <= max_pfn) { |
| capacity = e_pfn - max_pfn; |
| dest_pfn = max_pfn; |
| } else { |
| capacity = e_pfn - s_pfn; |
| dest_pfn = s_pfn; |
| } |
| |
| if (credits_left < capacity) |
| capacity = credits_left; |
| |
| pfns = xen_do_chunk(dest_pfn, dest_pfn + capacity, false); |
| done += pfns; |
| *last_pfn = (dest_pfn + pfns); |
| if (pfns < capacity) |
| break; |
| credits_left -= pfns; |
| } |
| return done; |
| } |
| |
| static void __init xen_set_identity_and_release_chunk( |
| unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, |
| unsigned long *released, unsigned long *identity) |
| { |
| unsigned long pfn; |
| |
| /* |
| * If the PFNs are currently mapped, the VA mapping also needs |
| * to be updated to be 1:1. |
| */ |
| for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++) |
| (void)HYPERVISOR_update_va_mapping( |
| (unsigned long)__va(pfn << PAGE_SHIFT), |
| mfn_pte(pfn, PAGE_KERNEL_IO), 0); |
| |
| if (start_pfn < nr_pages) |
| *released += xen_release_chunk( |
| start_pfn, min(end_pfn, nr_pages)); |
| |
| *identity += set_phys_range_identity(start_pfn, end_pfn); |
| } |
| |
| static unsigned long __init xen_set_identity_and_release( |
| const struct e820entry *list, size_t map_size, unsigned long nr_pages) |
| { |
| phys_addr_t start = 0; |
| unsigned long released = 0; |
| unsigned long identity = 0; |
| const struct e820entry *entry; |
| int i; |
| |
| /* |
| * Combine non-RAM regions and gaps until a RAM region (or the |
| * end of the map) is reached, then set the 1:1 map and |
| * release the pages (if available) in those non-RAM regions. |
| * |
| * The combined non-RAM regions are rounded to a whole number |
| * of pages so any partial pages are accessible via the 1:1 |
| * mapping. This is needed for some BIOSes that put (for |
| * example) the DMI tables in a reserved region that begins on |
| * a non-page boundary. |
| */ |
| for (i = 0, entry = list; i < map_size; i++, entry++) { |
| phys_addr_t end = entry->addr + entry->size; |
| if (entry->type == E820_RAM || i == map_size - 1) { |
| unsigned long start_pfn = PFN_DOWN(start); |
| unsigned long end_pfn = PFN_UP(end); |
| |
| if (entry->type == E820_RAM) |
| end_pfn = PFN_UP(entry->addr); |
| |
| if (start_pfn < end_pfn) |
| xen_set_identity_and_release_chunk( |
| start_pfn, end_pfn, nr_pages, |
| &released, &identity); |
| |
| start = end; |
| } |
| } |
| |
| if (released) |
| printk(KERN_INFO "Released %lu pages of unused memory\n", released); |
| if (identity) |
| printk(KERN_INFO "Set %ld page(s) to 1-1 mapping\n", identity); |
| |
| return released; |
| } |
| |
| static unsigned long __init xen_get_max_pages(void) |
| { |
| unsigned long max_pages = MAX_DOMAIN_PAGES; |
| domid_t domid = DOMID_SELF; |
| int ret; |
| |
| /* |
| * For the initial domain we use the maximum reservation as |
| * the maximum page. |
| * |
| * For guest domains the current maximum reservation reflects |
| * the current maximum rather than the static maximum. In this |
| * case the e820 map provided to us will cover the static |
| * maximum region. |
| */ |
| if (xen_initial_domain()) { |
| ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid); |
| if (ret > 0) |
| max_pages = ret; |
| } |
| |
| return min(max_pages, MAX_DOMAIN_PAGES); |
| } |
| |
| static void xen_align_and_add_e820_region(u64 start, u64 size, int type) |
| { |
| u64 end = start + size; |
| |
| /* Align RAM regions to page boundaries. */ |
| if (type == E820_RAM) { |
| start = PAGE_ALIGN(start); |
| end &= ~((u64)PAGE_SIZE - 1); |
| } |
| |
| e820_add_region(start, end - start, type); |
| } |
| |
| /** |
| * machine_specific_memory_setup - Hook for machine specific memory setup. |
| **/ |
| char * __init xen_memory_setup(void) |
| { |
| static struct e820entry map[E820MAX] __initdata; |
| |
| unsigned long max_pfn = xen_start_info->nr_pages; |
| unsigned long long mem_end; |
| int rc; |
| struct xen_memory_map memmap; |
| unsigned long max_pages; |
| unsigned long last_pfn = 0; |
| unsigned long extra_pages = 0; |
| unsigned long populated; |
| int i; |
| int op; |
| |
| max_pfn = min(MAX_DOMAIN_PAGES, max_pfn); |
| mem_end = PFN_PHYS(max_pfn); |
| |
| memmap.nr_entries = E820MAX; |
| set_xen_guest_handle(memmap.buffer, map); |
| |
| op = xen_initial_domain() ? |
| XENMEM_machine_memory_map : |
| XENMEM_memory_map; |
| rc = HYPERVISOR_memory_op(op, &memmap); |
| if (rc == -ENOSYS) { |
| BUG_ON(xen_initial_domain()); |
| memmap.nr_entries = 1; |
| map[0].addr = 0ULL; |
| map[0].size = mem_end; |
| /* 8MB slack (to balance backend allocations). */ |
| map[0].size += 8ULL << 20; |
| map[0].type = E820_RAM; |
| rc = 0; |
| } |
| BUG_ON(rc); |
| |
| /* Make sure the Xen-supplied memory map is well-ordered. */ |
| sanitize_e820_map(map, memmap.nr_entries, &memmap.nr_entries); |
| |
| max_pages = xen_get_max_pages(); |
| if (max_pages > max_pfn) |
| extra_pages += max_pages - max_pfn; |
| |
| /* |
| * Set P2M for all non-RAM pages and E820 gaps to be identity |
| * type PFNs. Any RAM pages that would be made inaccesible by |
| * this are first released. |
| */ |
| xen_released_pages = xen_set_identity_and_release( |
| map, memmap.nr_entries, max_pfn); |
| |
| /* |
| * Populate back the non-RAM pages and E820 gaps that had been |
| * released. */ |
| populated = xen_populate_chunk(map, memmap.nr_entries, |
| max_pfn, &last_pfn, xen_released_pages); |
| |
| xen_released_pages -= populated; |
| extra_pages += xen_released_pages; |
| |
| if (last_pfn > max_pfn) { |
| max_pfn = min(MAX_DOMAIN_PAGES, last_pfn); |
| mem_end = PFN_PHYS(max_pfn); |
| } |
| /* |
| * Clamp the amount of extra memory to a EXTRA_MEM_RATIO |
| * factor the base size. On non-highmem systems, the base |
| * size is the full initial memory allocation; on highmem it |
| * is limited to the max size of lowmem, so that it doesn't |
| * get completely filled. |
| * |
| * In principle there could be a problem in lowmem systems if |
| * the initial memory is also very large with respect to |
| * lowmem, but we won't try to deal with that here. |
| */ |
| extra_pages = min(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)), |
| extra_pages); |
| i = 0; |
| while (i < memmap.nr_entries) { |
| u64 addr = map[i].addr; |
| u64 size = map[i].size; |
| u32 type = map[i].type; |
| |
| if (type == E820_RAM) { |
| if (addr < mem_end) { |
| size = min(size, mem_end - addr); |
| } else if (extra_pages) { |
| size = min(size, (u64)extra_pages * PAGE_SIZE); |
| extra_pages -= size / PAGE_SIZE; |
| xen_add_extra_mem(addr, size); |
| } else |
| type = E820_UNUSABLE; |
| } |
| |
| xen_align_and_add_e820_region(addr, size, type); |
| |
| map[i].addr += size; |
| map[i].size -= size; |
| if (map[i].size == 0) |
| i++; |
| } |
| |
| /* |
| * In domU, the ISA region is normal, usable memory, but we |
| * reserve ISA memory anyway because too many things poke |
| * about in there. |
| */ |
| e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, |
| E820_RESERVED); |
| |
| /* |
| * Reserve Xen bits: |
| * - mfn_list |
| * - xen_start_info |
| * See comment above "struct start_info" in <xen/interface/xen.h> |
| */ |
| memblock_reserve(__pa(xen_start_info->mfn_list), |
| xen_start_info->pt_base - xen_start_info->mfn_list); |
| |
| sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); |
| |
| return "Xen"; |
| } |
| |
| /* |
| * Set the bit indicating "nosegneg" library variants should be used. |
| * We only need to bother in pure 32-bit mode; compat 32-bit processes |
| * can have un-truncated segments, so wrapping around is allowed. |
| */ |
| static void __init fiddle_vdso(void) |
| { |
| #ifdef CONFIG_X86_32 |
| u32 *mask; |
| mask = VDSO32_SYMBOL(&vdso32_int80_start, NOTE_MASK); |
| *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT; |
| mask = VDSO32_SYMBOL(&vdso32_sysenter_start, NOTE_MASK); |
| *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT; |
| #endif |
| } |
| |
| static int __cpuinit register_callback(unsigned type, const void *func) |
| { |
| struct callback_register callback = { |
| .type = type, |
| .address = XEN_CALLBACK(__KERNEL_CS, func), |
| .flags = CALLBACKF_mask_events, |
| }; |
| |
| return HYPERVISOR_callback_op(CALLBACKOP_register, &callback); |
| } |
| |
| void __cpuinit xen_enable_sysenter(void) |
| { |
| int ret; |
| unsigned sysenter_feature; |
| |
| #ifdef CONFIG_X86_32 |
| sysenter_feature = X86_FEATURE_SEP; |
| #else |
| sysenter_feature = X86_FEATURE_SYSENTER32; |
| #endif |
| |
| if (!boot_cpu_has(sysenter_feature)) |
| return; |
| |
| ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target); |
| if(ret != 0) |
| setup_clear_cpu_cap(sysenter_feature); |
| } |
| |
| void __cpuinit xen_enable_syscall(void) |
| { |
| #ifdef CONFIG_X86_64 |
| int ret; |
| |
| ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target); |
| if (ret != 0) { |
| printk(KERN_ERR "Failed to set syscall callback: %d\n", ret); |
| /* Pretty fatal; 64-bit userspace has no other |
| mechanism for syscalls. */ |
| } |
| |
| if (boot_cpu_has(X86_FEATURE_SYSCALL32)) { |
| ret = register_callback(CALLBACKTYPE_syscall32, |
| xen_syscall32_target); |
| if (ret != 0) |
| setup_clear_cpu_cap(X86_FEATURE_SYSCALL32); |
| } |
| #endif /* CONFIG_X86_64 */ |
| } |
| |
| void __init xen_arch_setup(void) |
| { |
| xen_panic_handler_init(); |
| |
| HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments); |
| HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables); |
| |
| if (!xen_feature(XENFEAT_auto_translated_physmap)) |
| HYPERVISOR_vm_assist(VMASST_CMD_enable, |
| VMASST_TYPE_pae_extended_cr3); |
| |
| if (register_callback(CALLBACKTYPE_event, xen_hypervisor_callback) || |
| register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback)) |
| BUG(); |
| |
| xen_enable_sysenter(); |
| xen_enable_syscall(); |
| |
| #ifdef CONFIG_ACPI |
| if (!(xen_start_info->flags & SIF_INITDOMAIN)) { |
| printk(KERN_INFO "ACPI in unprivileged domain disabled\n"); |
| disable_acpi(); |
| } |
| #endif |
| |
| memcpy(boot_command_line, xen_start_info->cmd_line, |
| MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ? |
| COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE); |
| |
| /* Set up idle, making sure it calls safe_halt() pvop */ |
| #ifdef CONFIG_X86_32 |
| boot_cpu_data.hlt_works_ok = 1; |
| #endif |
| disable_cpuidle(); |
| disable_cpufreq(); |
| WARN_ON(set_pm_idle_to_default()); |
| fiddle_vdso(); |
| } |