return -1;
}
-
-
int v3_init_mem_map(struct v3_vm_info * vm) {
struct v3_mem_map * map = &(vm->mem_map);
addr_t mem_pages = vm->mem_size >> 12;
map->mem_regions.rb_node = NULL;
-
// There is an underlying region that contains all of the guest memory
// PrintDebug("Mapping %d pages of memory (%u bytes)\n", (int)mem_pages, (uint_t)info->mem_size);
// 2MB page alignment needed for 2MB hardware nested paging
map->base_region.guest_start = 0;
map->base_region.guest_end = mem_pages * PAGE_SIZE_4KB;
- map->base_region.host_addr = (addr_t)V3_AllocAlignedPages(mem_pages, PAGE_SIZE_2MB);
+
+#ifdef CONFIG_ALIGNED_PG_ALLOC
+ map->base_region.host_addr = (addr_t)V3_AllocAlignedPages(mem_pages, vm->mem_align);
+#else
+ map->base_region.host_addr = (addr_t)V3_AllocPages(mem_pages);
+#endif
map->base_region.flags.read = 1;
map->base_region.flags.write = 1;
-/* Search the "hooked" memory regions for a region that ends after the given address. If the
- * address is invalid, return NULL. Else, return the first region found or the base region if no
- * region ends after the given address.
+/* Given an address, find the successor region. If the address is within a region, return that
+ * region. Input is an address, because the address may not have a region associated with it.
+ *
+ * Returns a region following or touching the given address. If address is invalid, NULL is
+ * returned, else the base region is returned if no region exists at or after the given address.
*/
struct v3_mem_region * v3_get_next_mem_region( struct v3_vm_info * vm, uint16_t core_id, addr_t guest_addr) {
- struct rb_node * n = vm->mem_map.mem_regions.rb_node;
- struct v3_mem_region * reg = NULL;
-
- // Keep going to the right in the tree while the address is greater than the current region's
- // end address.
- while (n) {
- reg = rb_entry(n, struct v3_mem_region, tree_node);
- if (guest_addr >= reg->guest_end) { // reg is [start,end)
- n = n->rb_right;
- } else {
- if ((core_id == reg->core_id) || (reg->core_id == V3_MEM_CORE_ANY)) {
- return reg;
- } else {
- n = n->rb_right;
+ struct rb_node * current_n = vm->mem_map.mem_regions.rb_node;
+ struct rb_node * successor_n = NULL; /* left-most node greater than guest_addr */
+ struct v3_mem_region * current_r = NULL;
+
+ /* current_n tries to find the region containing guest_addr, going right when smaller and left when
+ * greater. Each time current_n becomes greater than guest_addr, update successor <- current_n.
+ * current_n becomes successively closer to guest_addr than the previous time it was greater
+ * than guest_addr.
+ */
+
+ /* | is address, ---- is region, + is intersection */
+ while (current_n) {
+ current_r = rb_entry(current_n, struct v3_mem_region, tree_node);
+ if (current_r->guest_start > guest_addr) { /* | ---- */
+ successor_n = current_n;
+ current_n = current_n->rb_left;
+ } else {
+ if (current_r->guest_end > guest_addr) {
+ return current_r; /* +--- or --+- */
}
- }
+ current_n = current_n->rb_right; /* ---- | */
+ }
}
- // There is no registered region, so we check if it's a valid address in the base region
+ /* Address does not have its own region. Check if it's a valid address in the base region */
if (guest_addr >= vm->mem_map.base_region.guest_end) {
PrintError("%s: Guest Address Exceeds Base Memory Size (ga=%p), (limit=%p)\n",
}
+// Determine if a given address can be handled by a large page of the requested size
+uint32_t v3_get_max_page_size(struct guest_info * core, addr_t fault_addr, uint32_t req_size) {
+ addr_t pg_start = 0UL, pg_end = 0UL; // large page containing the faulting addres
+ struct v3_mem_region * pg_next_reg = NULL; // next immediate mem reg after page start addr
+ uint32_t page_size = PAGE_SIZE_4KB;
+
+ /* If the guest has been configured for large pages, then we must check for hooked regions of
+ * memory which may overlap with the large page containing the faulting address (due to
+ * potentially differing access policies in place for e.g. i/o devices and APIC). A large page
+ * can be used if a) no region overlaps the page [or b) a region does overlap but fully contains
+ * the page]. The [bracketed] text pertains to the #if 0'd code below, state D. TODO modify this
+ * note if someone decides to enable this optimization. It can be tested with the SeaStar
+ * mapping.
+ *
+ * Examples: (CAPS regions are returned by v3_get_next_mem_region; state A returns the base reg)
+ *
+ * |region| |region| 2MiB mapped (state A)
+ * |reg| |REG| 2MiB mapped (state B)
+ * |region| |reg| |REG| |region| |reg| 4KiB mapped (state C)
+ * |reg| |reg| |--REGION---| [2MiB mapped (state D)]
+ * |--------------------------------------------| RAM
+ * ^ fault addr
+ * |----|----|----|----|----|page|----|----|----| 2MB pages
+ * >>>>>>>>>>>>>>>>>>>> search space
+ */
+
+
+ // guest page maps to a host page + offset (so when we shift, it aligns with a host page)
+ switch (req_size) {
+ case PAGE_SIZE_4KB:
+ return PAGE_SIZE_4KB;
+ case PAGE_SIZE_2MB:
+ pg_start = PAGE_ADDR_2MB(fault_addr);
+ pg_end = (pg_start + PAGE_SIZE_2MB);
+ break;
+ case PAGE_SIZE_4MB:
+ pg_start = PAGE_ADDR_4MB(fault_addr);
+ pg_end = (pg_start + PAGE_SIZE_4MB);
+ break;
+ case PAGE_SIZE_1GB:
+ pg_start = PAGE_ADDR_1GB(fault_addr);
+ pg_end = (pg_start + PAGE_SIZE_1GB);
+ break;
+ default:
+ PrintError("Invalid large page size requested.\n");
+ return -1;
+ }
+
+ //PrintDebug("%s: page [%p,%p) contains address\n", __FUNCTION__, (void *)pg_start, (void *)pg_end);
+
+ pg_next_reg = v3_get_next_mem_region(core->vm_info, core->cpu_id, pg_start);
+ if (pg_next_reg == NULL) {
+ PrintError("%s: Error: address not in base region, %p\n", __FUNCTION__, (void *)fault_addr);
+ return PAGE_SIZE_4KB;
+ }
+
+ if (pg_next_reg->flags.base == 1) {
+ page_size = req_size; // State A
+ //PrintDebug("%s: base region [%p,%p) contains page.\n", __FUNCTION__,
+ // (void *)pg_next_reg->guest_start, (void *)pg_next_reg->guest_end);
+ } else {
+#if 0 // State B/C and D optimization
+ if ((pg_next_reg->guest_end >= pg_end) &&
+ ((pg_next_reg->guest_start >= pg_end) || (pg_next_reg->guest_start <= pg_start))) {
+ page_size = req_size;
+ }
+
+ PrintDebug("%s: region [%p,%p) %s partially overlap with page\n", __FUNCTION__,
+ (void *)pg_next_reg->guest_start, (void *)pg_next_reg->guest_end,
+ (page_size == req_size) ? "does not" : "does");
+
+#else // State B/C
+ if (pg_next_reg->guest_start >= pg_end) {
+
+ page_size = req_size;
+ }
+
+ PrintDebug("%s: region [%p,%p) %s overlap with page\n", __FUNCTION__,
+ (void *)pg_next_reg->guest_start, (void *)pg_next_reg->guest_end,
+ (page_size == req_size) ? "does not" : "does");
+
+#endif
+ }
+
+ return page_size;
+}
+
+// For an address on a page of size page_size, compute the actual alignment
+// of the physical page it maps to
+uint32_t v3_compute_page_alignment(addr_t page_addr)
+{
+ if (PAGE_OFFSET_1GB(page_addr) == 0) {
+ return PAGE_SIZE_1GB;
+ } else if (PAGE_OFFSET_4MB(page_addr) == 0) {
+ return PAGE_SIZE_4MB;
+ } else if (PAGE_OFFSET_2MB(page_addr) == 0) {
+ return PAGE_SIZE_2MB;
+ } else if (PAGE_OFFSET_4KB(page_addr) == 0) {
+ return PAGE_SIZE_4KB;
+ } else {
+ PrintError("Non-page aligned address passed to %s.\n", __FUNCTION__);
+ return 0;
+ }
+}
void v3_print_mem_map(struct v3_vm_info * vm) {
struct rb_node * node = v3_rb_first(&(vm->mem_map.mem_regions));
