__set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
}
-static unsigned long __init xen_release_chunk(phys_addr_t start_addr,
- phys_addr_t end_addr)
+static unsigned long __init xen_release_chunk(unsigned long start,
+ unsigned long end)
{
struct xen_memory_reservation reservation = {
.address_bits = 0,
.extent_order = 0,
.domid = DOMID_SELF
};
- unsigned long start, end;
unsigned long len = 0;
unsigned long pfn;
int ret;
- start = PFN_UP(start_addr);
- end = PFN_DOWN(end_addr);
-
- if (end <= start)
- return 0;
-
for(pfn = start; pfn < end; pfn++) {
unsigned long mfn = pfn_to_mfn(pfn);
return len;
}
-static unsigned long __init xen_return_unused_memory(
- unsigned long max_pfn, const struct e820entry *map, int nr_map)
+static unsigned long __init xen_set_identity_and_release(
+ const struct e820entry *list, size_t map_size, unsigned long nr_pages)
{
- phys_addr_t max_addr = PFN_PHYS(max_pfn);
- phys_addr_t last_end = ISA_END_ADDRESS;
+ phys_addr_t start = 0;
unsigned long released = 0;
- int i;
-
- /* Free any unused memory above the low 1Mbyte. */
- for (i = 0; i < nr_map && last_end < max_addr; i++) {
- phys_addr_t end = map[i].addr;
- end = min(max_addr, end);
-
- if (last_end < end)
- released += xen_release_chunk(last_end, end);
- last_end = max(last_end, map[i].addr + map[i].size);
- }
-
- if (last_end < max_addr)
- released += xen_release_chunk(last_end, max_addr);
-
- printk(KERN_INFO "released %lu pages of unused memory\n", released);
- return released;
-}
-
-static unsigned long __init xen_set_identity(const struct e820entry *list,
- ssize_t map_size)
-{
- phys_addr_t last = xen_initial_domain() ? 0 : ISA_END_ADDRESS;
- phys_addr_t start_pci = last;
- const struct e820entry *entry;
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 start = entry->addr;
- phys_addr_t end = start + entry->size;
+ phys_addr_t end = entry->addr + entry->size;
- if (start < last)
- start = last;
+ if (entry->type == E820_RAM || i == map_size - 1) {
+ unsigned long start_pfn = PFN_DOWN(start);
+ unsigned long end_pfn = PFN_UP(end);
- if (end <= start)
- continue;
+ if (entry->type == E820_RAM)
+ end_pfn = PFN_UP(entry->addr);
- /* Skip over the 1MB region. */
- if (last > end)
- continue;
+ if (start_pfn < end_pfn) {
+ if (start_pfn < nr_pages)
+ released += xen_release_chunk(
+ start_pfn, min(end_pfn, nr_pages));
- if ((entry->type == E820_RAM) || (entry->type == E820_UNUSABLE)) {
- if (start > start_pci)
identity += set_phys_range_identity(
- PFN_UP(start_pci), PFN_DOWN(start));
-
- /* Without saving 'last' we would gooble RAM too
- * at the end of the loop. */
- last = end;
- start_pci = end;
- continue;
+ start_pfn, end_pfn);
+ }
+ start = end;
}
- start_pci = min(start, start_pci);
- last = end;
}
- if (last > start_pci)
- identity += set_phys_range_identity(
- PFN_UP(start_pci), PFN_DOWN(last));
- return identity;
+
+ printk(KERN_INFO "Released %lu pages of unused memory\n", released);
+ printk(KERN_INFO "Set %ld page(s) to 1-1 mapping\n", identity);
+
+ return released;
}
static unsigned long __init xen_get_max_pages(void)
struct xen_memory_map memmap;
unsigned long max_pages;
unsigned long extra_pages = 0;
- unsigned long identity_pages = 0;
int i;
int op;
if (max_pages > max_pfn)
extra_pages += max_pages - max_pfn;
- xen_released_pages = xen_return_unused_memory(max_pfn, map,
- memmap.nr_entries);
+ /*
+ * 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);
extra_pages += xen_released_pages;
/*
* In domU, the ISA region is normal, usable memory, but we
* reserve ISA memory anyway because too many things poke
* about in there.
- *
- * In Dom0, the host E820 information can leave gaps in the
- * ISA range, which would cause us to release those pages. To
- * avoid this, we unconditionally reserve them here.
*/
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);
- /*
- * Set P2M for all non-RAM pages and E820 gaps to be identity
- * type PFNs.
- */
- identity_pages = xen_set_identity(e820.map, e820.nr_map);
- printk(KERN_INFO "Set %ld page(s) to 1-1 mapping.\n", identity_pages);
return "Xen";
}
git.openpandora.org / pandora-kernel.git / blobdiff