OpenCloudOS-Kernel/arch/x86/xen/setup.c

894 lines
24 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/numa.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"
#include "p2m.h"
#include "mmu.h"
/* 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;
/* E820 map used during setting up memory. */
static struct e820entry xen_e820_map[E820MAX] __initdata;
static u32 xen_e820_map_entries __initdata;
/*
* Buffer used to remap identity mapped pages. We only need the virtual space.
* The physical page behind this address is remapped as needed to different
* buffer pages.
*/
#define REMAP_SIZE (P2M_PER_PAGE - 3)
static struct {
unsigned long next_area_mfn;
unsigned long target_pfn;
unsigned long size;
unsigned long mfns[REMAP_SIZE];
} xen_remap_buf __initdata __aligned(PAGE_SIZE);
static unsigned long xen_remap_mfn __initdata = INVALID_P2M_ENTRY;
/*
* 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(phys_addr_t start, phys_addr_t size)
{
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);
}
static void __init xen_del_extra_mem(phys_addr_t start, phys_addr_t size)
{
int i;
phys_addr_t start_r, size_r;
for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
start_r = xen_extra_mem[i].start;
size_r = xen_extra_mem[i].size;
/* Start of region. */
if (start_r == start) {
BUG_ON(size > size_r);
xen_extra_mem[i].start += size;
xen_extra_mem[i].size -= size;
break;
}
/* End of region. */
if (start_r + size_r == start + size) {
BUG_ON(size > size_r);
xen_extra_mem[i].size -= size;
break;
}
/* Mid of region. */
if (start > start_r && start < start_r + size_r) {
BUG_ON(start + size > start_r + size_r);
xen_extra_mem[i].size = start - start_r;
/* Calling memblock_reserve() again is okay. */
xen_add_extra_mem(start + size, start_r + size_r -
(start + size));
break;
}
}
memblock_free(start, size);
}
/*
* Called during boot before the p2m list can take entries beyond the
* hypervisor supplied p2m list. Entries in extra mem are to be regarded as
* invalid.
*/
unsigned long __ref xen_chk_extra_mem(unsigned long pfn)
{
int i;
phys_addr_t addr = PFN_PHYS(pfn);
for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
if (addr >= xen_extra_mem[i].start &&
addr < xen_extra_mem[i].start + xen_extra_mem[i].size)
return INVALID_P2M_ENTRY;
}
return IDENTITY_FRAME(pfn);
}
/*
* Mark all pfns of extra mem as invalid in p2m list.
*/
void __init xen_inv_extra_mem(void)
{
unsigned long pfn, pfn_s, pfn_e;
int i;
for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
if (!xen_extra_mem[i].size)
continue;
pfn_s = PFN_DOWN(xen_extra_mem[i].start);
pfn_e = PFN_UP(xen_extra_mem[i].start + xen_extra_mem[i].size);
for (pfn = pfn_s; pfn < pfn_e; pfn++)
set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
}
}
/*
* Finds the next RAM pfn available in the E820 map after min_pfn.
* This function updates min_pfn with the pfn found and returns
* the size of that range or zero if not found.
*/
static unsigned long __init xen_find_pfn_range(unsigned long *min_pfn)
{
const struct e820entry *entry = xen_e820_map;
unsigned int i;
unsigned long done = 0;
for (i = 0; i < xen_e820_map_entries; i++, entry++) {
unsigned long s_pfn;
unsigned long e_pfn;
if (entry->type != E820_RAM)
continue;
e_pfn = PFN_DOWN(entry->addr + entry->size);
/* We only care about E820 after this */
if (e_pfn < *min_pfn)
continue;
s_pfn = PFN_UP(entry->addr);
/* If min_pfn falls within the E820 entry, we want to start
* at the min_pfn PFN.
*/
if (s_pfn <= *min_pfn) {
done = e_pfn - *min_pfn;
} else {
done = e_pfn - s_pfn;
*min_pfn = s_pfn;
}
break;
}
return done;
}
static int __init xen_free_mfn(unsigned long mfn)
{
struct xen_memory_reservation reservation = {
.address_bits = 0,
.extent_order = 0,
.domid = DOMID_SELF
};
set_xen_guest_handle(reservation.extent_start, &mfn);
reservation.nr_extents = 1;
return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
}
/*
* This releases a chunk of memory and then does the identity map. It's used
* as a fallback if the remapping fails.
*/
static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn,
unsigned long end_pfn, unsigned long nr_pages)
{
unsigned long pfn, end;
int ret;
WARN_ON(start_pfn > end_pfn);
/* Release pages first. */
end = min(end_pfn, nr_pages);
for (pfn = start_pfn; pfn < end; pfn++) {
unsigned long mfn = pfn_to_mfn(pfn);
/* Make sure pfn exists to start with */
if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn)
continue;
ret = xen_free_mfn(mfn);
WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret);
if (ret == 1) {
xen_released_pages++;
if (!__set_phys_to_machine(pfn, INVALID_P2M_ENTRY))
break;
} else
break;
}
set_phys_range_identity(start_pfn, end_pfn);
}
/*
* Helper function to update the p2m and m2p tables and kernel mapping.
*/
static void __init xen_update_mem_tables(unsigned long pfn, unsigned long mfn)
{
struct mmu_update update = {
.ptr = ((uint64_t)mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE,
.val = pfn
};
/* Update p2m */
if (!set_phys_to_machine(pfn, mfn)) {
WARN(1, "Failed to set p2m mapping for pfn=%ld mfn=%ld\n",
pfn, mfn);
BUG();
}
/* Update m2p */
if (HYPERVISOR_mmu_update(&update, 1, NULL, DOMID_SELF) < 0) {
WARN(1, "Failed to set m2p mapping for mfn=%ld pfn=%ld\n",
mfn, pfn);
BUG();
}
/* Update kernel mapping, but not for highmem. */
if (pfn >= PFN_UP(__pa(high_memory - 1)))
return;
if (HYPERVISOR_update_va_mapping((unsigned long)__va(pfn << PAGE_SHIFT),
mfn_pte(mfn, PAGE_KERNEL), 0)) {
WARN(1, "Failed to update kernel mapping for mfn=%ld pfn=%ld\n",
mfn, pfn);
BUG();
}
}
/*
* This function updates the p2m and m2p tables with an identity map from
* start_pfn to start_pfn+size and prepares remapping the underlying RAM of the
* original allocation at remap_pfn. The information needed for remapping is
* saved in the memory itself to avoid the need for allocating buffers. The
* complete remap information is contained in a list of MFNs each containing
* up to REMAP_SIZE MFNs and the start target PFN for doing the remap.
* This enables us to preserve the original mfn sequence while doing the
* remapping at a time when the memory management is capable of allocating
* virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and
* its callers.
*/
static void __init xen_do_set_identity_and_remap_chunk(
unsigned long start_pfn, unsigned long size, unsigned long remap_pfn)
{
unsigned long buf = (unsigned long)&xen_remap_buf;
unsigned long mfn_save, mfn;
unsigned long ident_pfn_iter, remap_pfn_iter;
unsigned long ident_end_pfn = start_pfn + size;
unsigned long left = size;
unsigned int i, chunk;
WARN_ON(size == 0);
BUG_ON(xen_feature(XENFEAT_auto_translated_physmap));
mfn_save = virt_to_mfn(buf);
for (ident_pfn_iter = start_pfn, remap_pfn_iter = remap_pfn;
ident_pfn_iter < ident_end_pfn;
ident_pfn_iter += REMAP_SIZE, remap_pfn_iter += REMAP_SIZE) {
chunk = (left < REMAP_SIZE) ? left : REMAP_SIZE;
/* Map first pfn to xen_remap_buf */
mfn = pfn_to_mfn(ident_pfn_iter);
set_pte_mfn(buf, mfn, PAGE_KERNEL);
/* Save mapping information in page */
xen_remap_buf.next_area_mfn = xen_remap_mfn;
xen_remap_buf.target_pfn = remap_pfn_iter;
xen_remap_buf.size = chunk;
for (i = 0; i < chunk; i++)
xen_remap_buf.mfns[i] = pfn_to_mfn(ident_pfn_iter + i);
/* Put remap buf into list. */
xen_remap_mfn = mfn;
/* Set identity map */
set_phys_range_identity(ident_pfn_iter, ident_pfn_iter + chunk);
left -= chunk;
}
/* Restore old xen_remap_buf mapping */
set_pte_mfn(buf, mfn_save, PAGE_KERNEL);
}
/*
* This function takes a contiguous pfn range that needs to be identity mapped
* and:
*
* 1) Finds a new range of pfns to use to remap based on E820 and remap_pfn.
* 2) Calls the do_ function to actually do the mapping/remapping work.
*
* The goal is to not allocate additional memory but to remap the existing
* pages. In the case of an error the underlying memory is simply released back
* to Xen and not remapped.
*/
static unsigned long __init xen_set_identity_and_remap_chunk(
unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages,
unsigned long remap_pfn)
{
unsigned long pfn;
unsigned long i = 0;
unsigned long n = end_pfn - start_pfn;
while (i < n) {
unsigned long cur_pfn = start_pfn + i;
unsigned long left = n - i;
unsigned long size = left;
unsigned long remap_range_size;
/* Do not remap pages beyond the current allocation */
if (cur_pfn >= nr_pages) {
/* Identity map remaining pages */
set_phys_range_identity(cur_pfn, cur_pfn + size);
break;
}
if (cur_pfn + size > nr_pages)
size = nr_pages - cur_pfn;
remap_range_size = xen_find_pfn_range(&remap_pfn);
if (!remap_range_size) {
pr_warning("Unable to find available pfn range, not remapping identity pages\n");
xen_set_identity_and_release_chunk(cur_pfn,
cur_pfn + left, nr_pages);
break;
}
/* Adjust size to fit in current e820 RAM region */
if (size > remap_range_size)
size = remap_range_size;
xen_do_set_identity_and_remap_chunk(cur_pfn, size, remap_pfn);
/* Update variables to reflect new mappings. */
i += size;
remap_pfn += size;
}
/*
* 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);
return remap_pfn;
}
static void __init xen_set_identity_and_remap(unsigned long nr_pages)
{
phys_addr_t start = 0;
unsigned long last_pfn = nr_pages;
const struct e820entry *entry = xen_e820_map;
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
* remap the memory 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; i < xen_e820_map_entries; i++, entry++) {
phys_addr_t end = entry->addr + entry->size;
if (entry->type == E820_RAM || i == xen_e820_map_entries - 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)
last_pfn = xen_set_identity_and_remap_chunk(
start_pfn, end_pfn, nr_pages,
last_pfn);
start = end;
}
}
pr_info("Released %ld page(s)\n", xen_released_pages);
}
/*
* Remap the memory prepared in xen_do_set_identity_and_remap_chunk().
* The remap information (which mfn remap to which pfn) is contained in the
* to be remapped memory itself in a linked list anchored at xen_remap_mfn.
* This scheme allows to remap the different chunks in arbitrary order while
* the resulting mapping will be independant from the order.
*/
void __init xen_remap_memory(void)
{
unsigned long buf = (unsigned long)&xen_remap_buf;
unsigned long mfn_save, mfn, pfn;
unsigned long remapped = 0;
unsigned int i;
unsigned long pfn_s = ~0UL;
unsigned long len = 0;
mfn_save = virt_to_mfn(buf);
while (xen_remap_mfn != INVALID_P2M_ENTRY) {
/* Map the remap information */
set_pte_mfn(buf, xen_remap_mfn, PAGE_KERNEL);
BUG_ON(xen_remap_mfn != xen_remap_buf.mfns[0]);
pfn = xen_remap_buf.target_pfn;
for (i = 0; i < xen_remap_buf.size; i++) {
mfn = xen_remap_buf.mfns[i];
xen_update_mem_tables(pfn, mfn);
remapped++;
pfn++;
}
if (pfn_s == ~0UL || pfn == pfn_s) {
pfn_s = xen_remap_buf.target_pfn;
len += xen_remap_buf.size;
} else if (pfn_s + len == xen_remap_buf.target_pfn) {
len += xen_remap_buf.size;
} else {
xen_del_extra_mem(PFN_PHYS(pfn_s), PFN_PHYS(len));
pfn_s = xen_remap_buf.target_pfn;
len = xen_remap_buf.size;
}
mfn = xen_remap_mfn;
xen_remap_mfn = xen_remap_buf.next_area_mfn;
}
if (pfn_s != ~0UL && len)
xen_del_extra_mem(PFN_PHYS(pfn_s), PFN_PHYS(len));
set_pte_mfn(buf, mfn_save, PAGE_KERNEL);
pr_info("Remapped %ld page(s)\n", remapped);
}
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 __init xen_align_and_add_e820_region(phys_addr_t start,
phys_addr_t size, int type)
{
phys_addr_t end = start + size;
/* Align RAM regions to page boundaries. */
if (type == E820_RAM) {
start = PAGE_ALIGN(start);
end &= ~((phys_addr_t)PAGE_SIZE - 1);
}
e820_add_region(start, end - start, type);
}
static void __init xen_ignore_unusable(void)
{
struct e820entry *entry = xen_e820_map;
unsigned int i;
for (i = 0; i < xen_e820_map_entries; i++, entry++) {
if (entry->type == E820_UNUSABLE)
entry->type = E820_RAM;
}
}
static unsigned long __init xen_count_remap_pages(unsigned long max_pfn)
{
unsigned long extra = 0;
const struct e820entry *entry = xen_e820_map;
int i;
for (i = 0; i < xen_e820_map_entries; i++, entry++) {
unsigned long start_pfn = PFN_DOWN(entry->addr);
unsigned long end_pfn = PFN_UP(entry->addr + entry->size);
if (start_pfn >= max_pfn)
break;
if (entry->type == E820_RAM)
continue;
if (end_pfn >= max_pfn)
end_pfn = max_pfn;
extra += end_pfn - start_pfn;
}
return extra;
}
/*
* Reserve Xen mfn_list.
* 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.
*/
static void __init xen_reserve_xen_mfnlist(void)
{
if (xen_start_info->mfn_list >= __START_KERNEL_map) {
memblock_reserve(__pa(xen_start_info->mfn_list),
xen_start_info->pt_base -
xen_start_info->mfn_list);
return;
}
memblock_reserve(PFN_PHYS(xen_start_info->first_p2m_pfn),
PFN_PHYS(xen_start_info->nr_p2m_frames));
}
/**
* machine_specific_memory_setup - Hook for machine specific memory setup.
**/
char * __init xen_memory_setup(void)
{
unsigned long max_pfn = xen_start_info->nr_pages;
phys_addr_t mem_end, addr, size, chunk_size;
u32 type;
int rc;
struct xen_memory_map memmap;
unsigned long max_pages;
unsigned long extra_pages = 0;
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, xen_e820_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;
xen_e820_map[0].addr = 0ULL;
xen_e820_map[0].size = mem_end;
/* 8MB slack (to balance backend allocations). */
xen_e820_map[0].size += 8ULL << 20;
xen_e820_map[0].type = E820_RAM;
rc = 0;
}
BUG_ON(rc);
BUG_ON(memmap.nr_entries == 0);
xen_e820_map_entries = memmap.nr_entries;
/*
* Xen won't allow a 1:1 mapping to be created to UNUSABLE
* regions, so if we're using the machine memory map leave the
* region as RAM as it is in the pseudo-physical map.
*
* UNUSABLE regions in domUs are not handled and will need
* a patch in the future.
*/
if (xen_initial_domain())
xen_ignore_unusable();
/* Make sure the Xen-supplied memory map is well-ordered. */
sanitize_e820_map(xen_e820_map, xen_e820_map_entries,
&xen_e820_map_entries);
max_pages = xen_get_max_pages();
if (max_pages > max_pfn)
extra_pages += max_pages - max_pfn;
/* How many extra pages do we need due to remapping? */
extra_pages += xen_count_remap_pages(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;
addr = xen_e820_map[0].addr;
size = xen_e820_map[0].size;
while (i < xen_e820_map_entries) {
chunk_size = size;
type = xen_e820_map[i].type;
if (type == E820_RAM) {
if (addr < mem_end) {
chunk_size = min(size, mem_end - addr);
} else if (extra_pages) {
chunk_size = min(size, PFN_PHYS(extra_pages));
extra_pages -= PFN_DOWN(chunk_size);
xen_add_extra_mem(addr, chunk_size);
xen_max_p2m_pfn = PFN_DOWN(addr + chunk_size);
} else
type = E820_UNUSABLE;
}
xen_align_and_add_e820_region(addr, chunk_size, type);
addr += chunk_size;
size -= chunk_size;
if (size == 0) {
i++;
if (i < xen_e820_map_entries) {
addr = xen_e820_map[i].addr;
size = xen_e820_map[i].size;
}
}
}
/*
* Set the rest as identity mapped, in case PCI BARs are
* located here.
*
* PFNs above MAX_P2M_PFN are considered identity mapped as
* well.
*/
set_phys_range_identity(addr / PAGE_SIZE, ~0ul);
/*
* 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);
sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
xen_reserve_xen_mfnlist();
/*
* Set identity map on non-RAM pages and prepare remapping the
* underlying RAM.
*/
xen_set_identity_and_remap(max_pfn);
return "Xen";
}
/*
* Machine specific memory setup for auto-translated guests.
*/
char * __init xen_auto_xlated_memory_setup(void)
{
struct xen_memory_map memmap;
int i;
int rc;
memmap.nr_entries = E820MAX;
set_xen_guest_handle(memmap.buffer, xen_e820_map);
rc = HYPERVISOR_memory_op(XENMEM_memory_map, &memmap);
if (rc < 0)
panic("No memory map (%d)\n", rc);
xen_e820_map_entries = memmap.nr_entries;
sanitize_e820_map(xen_e820_map, ARRAY_SIZE(xen_e820_map),
&xen_e820_map_entries);
for (i = 0; i < xen_e820_map_entries; i++)
e820_add_region(xen_e820_map[i].addr, xen_e820_map[i].size,
xen_e820_map[i].type);
xen_reserve_xen_mfnlist();
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
/*
* This could be called before selected_vdso32 is initialized, so
* just fiddle with both possible images. vdso_image_32_syscall
* can't be selected, since it only exists on 64-bit systems.
*/
u32 *mask;
mask = vdso_image_32_int80.data +
vdso_image_32_int80.sym_VDSO32_NOTE_MASK;
*mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
mask = vdso_image_32_sysenter.data +
vdso_image_32_sysenter.sym_VDSO32_NOTE_MASK;
*mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
#endif
}
static int 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 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 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_pvmmu_arch_setup(void)
{
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
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();
}
/* This function is not called for HVM domains */
void __init xen_arch_setup(void)
{
xen_panic_handler_init();
if (!xen_feature(XENFEAT_auto_translated_physmap))
xen_pvmmu_arch_setup();
#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 */
disable_cpuidle();
disable_cpufreq();
WARN_ON(xen_set_default_idle());
fiddle_vdso();
#ifdef CONFIG_NUMA
numa_off = 1;
#endif
}