564 lines
15 KiB
C
564 lines
15 KiB
C
/*
|
|
* 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++)
|
|
__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 credits = credits_left;
|
|
unsigned long s_pfn;
|
|
unsigned long e_pfn;
|
|
unsigned long pfns;
|
|
long capacity;
|
|
|
|
if (credits <= 0)
|
|
break;
|
|
|
|
if (entry->type != E820_RAM)
|
|
continue;
|
|
|
|
e_pfn = PFN_UP(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_DOWN(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 {
|
|
/* last_pfn MUST be within E820_RAM regions */
|
|
if (*last_pfn && e_pfn >= *last_pfn)
|
|
s_pfn = *last_pfn;
|
|
capacity = e_pfn - s_pfn;
|
|
dest_pfn = s_pfn;
|
|
}
|
|
/* If we had filled this E820_RAM entry, go to the next one. */
|
|
if (capacity <= 0)
|
|
continue;
|
|
|
|
if (credits > capacity)
|
|
credits = capacity;
|
|
|
|
pfns = xen_do_chunk(dest_pfn, dest_pfn + credits, false);
|
|
done += pfns;
|
|
credits_left -= pfns;
|
|
*last_pfn = (dest_pfn + 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>
|
|
* We tried to make the the memblock_reserve more selective so
|
|
* that it would be clear what region is reserved. Sadly we ran
|
|
* in the problem wherein on a 64-bit hypervisor with a 32-bit
|
|
* initial domain, the pt_base has the cr3 value which is not
|
|
* neccessarily where the pagetable starts! As Jan put it: "
|
|
* Actually, the adjustment turns out to be correct: The page
|
|
* tables for a 32-on-64 dom0 get allocated in the order "first L1",
|
|
* "first L2", "first L3", so the offset to the page table base is
|
|
* indeed 2. When reading xen/include/public/xen.h's comment
|
|
* very strictly, this is not a violation (since there nothing is said
|
|
* that the first thing in the page table space is pointed to by
|
|
* pt_base; I admit that this seems to be implied though, namely
|
|
* do I think that it is implied that the page table space is the
|
|
* range [pt_base, pt_base + nt_pt_frames), whereas that
|
|
* range here indeed is [pt_base - 2, pt_base - 2 + nt_pt_frames),
|
|
* which - without a priori knowledge - the kernel would have
|
|
* difficulty to figure out)." - so lets just fall back to the
|
|
* easy way and reserve the whole region.
|
|
*/
|
|
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();
|
|
}
|