/**
* 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";
}
/**
* 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);
/*
* 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(map, memmap.nr_entries);
/* 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";
}
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 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, 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;
/* */
map[0].size += 8ULL << 20;
map[0].type = E820_RAM;
rc = 0;
}
BUG_ON(rc);
/* */
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;
/*
*/
xen_released_pages = xen_set_identity_and_release(
map, memmap.nr_entries, max_pfn);
extra_pages += xen_released_pages;
/*
*/
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++;
}
/*
*/
e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS,
E820_RESERVED);
/*
*/
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";
}