1 // SPDX-License-Identifier: GPL-2.0
32 #include <xen/interface/memory.h>
35 #include <xen/hvc-console.h>
36 #include "xen-ops.h"
40 /* Memory map would allow PCI passthrough. */
43 /* E820 map used during setting up memory. */
46 /* Number of initially usable memory pages. */
54 #define REMAP_SIZE	(P2M_PER_PAGE - 3)
70 	arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit");  in xen_parse_512gb()
74 	arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit=");  in xen_parse_512gb()
97 			xen_extra_mem[i].n_pfns -= n_pfns;  in xen_del_extra_mem()
103 			xen_extra_mem[i].n_pfns -= n_pfns;  in xen_del_extra_mem()
109 			xen_extra_mem[i].n_pfns = start_pfn - start_r;  in xen_del_extra_mem()
111 			xen_add_extra_mem(start_pfn + n_pfns, start_r + size_r -  in xen_del_extra_mem()
156  * Finds the next RAM pfn available in the E820 map after min_pfn.
170 		if (entry->type != E820_TYPE_RAM)  in xen_find_pfn_range()
173 		e_pfn = PFN_DOWN(entry->addr + entry->size);  in xen_find_pfn_range()
179 		s_pfn = PFN_UP(entry->addr);  in xen_find_pfn_range()
185 			done = e_pfn - *min_pfn;  in xen_find_pfn_range()
187 			done = e_pfn - s_pfn;  in xen_find_pfn_range()
211  * This releases a chunk of memory and then does the identity map. It's used
278  * This function updates the p2m and m2p tables with an identity map from
281  * saved in the memory itself to avoid the need for allocating buffers. The
285  * remapping at a time when the memory management is capable of allocating
286  * virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and
308 		/* Map first pfn to xen_remap_buf */  in xen_do_set_identity_and_remap_chunk()
322 		/* Set identity map */  in xen_do_set_identity_and_remap_chunk()
325 		left -= chunk;  in xen_do_set_identity_and_remap_chunk()
339  * The goal is to not allocate additional memory but to remap the existing
340  * pages. In the case of an error the underlying memory is simply released back
348 	unsigned long n = end_pfn - start_pfn;  in xen_set_identity_and_remap_chunk()
355 		unsigned long left = n - i;  in xen_set_identity_and_remap_chunk()
361 			/* Identity map remaining pages */  in xen_set_identity_and_remap_chunk()
366 			size = ini_nr_pages - cur_pfn;  in xen_set_identity_and_remap_chunk()
405 	return remap_pages + min(end_pfn, ini_nr_pages) - start_pfn;  in xen_count_remap_pages()
418 	 * Combine non-RAM regions and gaps until a RAM region (or the  in xen_foreach_remap_area()
419 	 * end of the map) is reached, then call the provided function  in xen_foreach_remap_area()
420 	 * to perform its duty on the non-RAM region.  in xen_foreach_remap_area()
422 	 * The combined non-RAM regions are rounded to a whole number  in xen_foreach_remap_area()
426 	 * a non-page boundary.  in xen_foreach_remap_area()
429 		phys_addr_t end = entry->addr + entry->size;  in xen_foreach_remap_area()
430 		if (entry->type == E820_TYPE_RAM || i == xen_e820_table.nr_entries - 1) {  in xen_foreach_remap_area()
434 			if (entry->type == E820_TYPE_RAM)  in xen_foreach_remap_area()
435 				end_pfn = PFN_UP(entry->addr);  in xen_foreach_remap_area()
447  * Remap the memory prepared in xen_do_set_identity_and_remap_chunk().
449  * to be remapped memory itself in a linked list anchored at xen_remap_mfn.
465 		/* Map the remap information */  in xen_remap_memory()
525 	 * case the e820 map provided to us will cover the static  in xen_get_max_pages()
545 		end &= ~((phys_addr_t)PAGE_SIZE - 1);  in xen_align_and_add_e820_region()
548 		 * Don't allow adding memory not in E820 map while booting the  in xen_align_and_add_e820_region()
556 	e820__range_add(start, end - start, type);  in xen_align_and_add_e820_region()
565 		if (entry->type == E820_TYPE_UNUSABLE)  in xen_ignore_unusable()
566 			entry->type = E820_TYPE_RAM;  in xen_ignore_unusable()
583 		if (entry->type == E820_TYPE_RAM && entry->addr <= start &&  in xen_is_e820_reserved()
584 		    (entry->addr + entry->size) >= end)  in xen_is_e820_reserved()
594  * Find a free area in physical memory not yet reserved and compliant with
595  * E820 map.
596  * Used to relocate pre-allocated areas like initrd or p2m list which are in
597  * conflict with the to be used E820 map.
608 		if (entry->type != E820_TYPE_RAM || entry->size < size)  in xen_find_free_area()
610 		start = entry->addr;  in xen_find_free_area()
615 			if (start + size > entry->addr + entry->size)  in xen_find_free_area()
628  * Swap a non-RAM E820 map entry with RAM above ini_nr_pages.
629  * Note that the E820 map is modified accordingly, but the P2M map isn't yet.
639 	swap_addr = PAGE_ALIGN_DOWN(swap_entry->addr);  in xen_e820_swap_entry_with_ram()
640 	swap_size = PAGE_ALIGN(swap_entry->addr - swap_addr + swap_entry->size);  in xen_e820_swap_entry_with_ram()
644 		entry_end = entry->addr + entry->size;  in xen_e820_swap_entry_with_ram()
645 		if (entry->type == E820_TYPE_RAM && entry->size >= swap_size &&  in xen_e820_swap_entry_with_ram()
646 		    entry_end - swap_size >= mem_end) {  in xen_e820_swap_entry_with_ram()
648 			entry->size -= swap_size;  in xen_e820_swap_entry_with_ram()
650 			/* Add new entry at the end of E820 map. */  in xen_e820_swap_entry_with_ram()
656 			entry->type = swap_entry->type;  in xen_e820_swap_entry_with_ram()
657 			entry->addr = entry_end - swap_size +  in xen_e820_swap_entry_with_ram()
658 				      swap_addr - swap_entry->addr;  in xen_e820_swap_entry_with_ram()
659 			entry->size = swap_entry->size;  in xen_e820_swap_entry_with_ram()
662 			swap_entry->type = E820_TYPE_RAM;  in xen_e820_swap_entry_with_ram()
663 			swap_entry->addr = swap_addr;  in xen_e820_swap_entry_with_ram()
664 			swap_entry->size = swap_size;  in xen_e820_swap_entry_with_ram()
666 			/* Remember PFN<->MFN relation for P2M update. */  in xen_e820_swap_entry_with_ram()
667 			xen_add_remap_nonram(swap_addr, entry_end - swap_size,  in xen_e820_swap_entry_with_ram()
684  * Look for non-RAM memory types in a specific guest physical area and move
701 		if (entry->addr >= end)  in xen_e820_resolve_conflicts()
704 		if (entry->addr + entry->size > start &&  in xen_e820_resolve_conflicts()
705 		    entry->type == E820_TYPE_NVS)  in xen_e820_resolve_conflicts()
713  * Check for an area in physical memory to be usable for non-movable purposes.
714  * An area is considered to usable if the used E820 map lists it to be RAM or
728 	xen_raw_console_write(" memory conflicts with E820 map\n");  in xen_chk_is_e820_usable()
745 		if (dest_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off)  in xen_phys_memcpy()
746 			dest_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off;  in xen_phys_memcpy()
748 		if (src_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off)  in xen_phys_memcpy()
749 			src_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off;  in xen_phys_memcpy()
751 		to = early_memremap(dest - dest_off, dest_len + dest_off);  in xen_phys_memcpy()
752 		from = early_memremap(src - src_off, src_len + src_off);  in xen_phys_memcpy()
756 		n -= len;  in xen_phys_memcpy()
769 	if (xen_start_info->mfn_list >= __START_KERNEL_map) {  in xen_reserve_xen_mfnlist()
770 		start = __pa(xen_start_info->mfn_list);  in xen_reserve_xen_mfnlist()
771 		size = PFN_ALIGN(xen_start_info->nr_pages *  in xen_reserve_xen_mfnlist()
774 		start = PFN_PHYS(xen_start_info->first_p2m_pfn);  in xen_reserve_xen_mfnlist()
775 		size = PFN_PHYS(xen_start_info->nr_p2m_frames);  in xen_reserve_xen_mfnlist()
787  * xen_memory_setup - Hook for machine specific memory setup.
803 	ini_nr_pages = min(xen_get_pages_limit(), xen_start_info->nr_pages);  in xen_memory_setup()
817 	if (rc == -ENOSYS) {  in xen_memory_setup()
834 		 * regions, so if we're using the machine memory map leave the  in xen_memory_setup()
835 		 * region as RAM as it is in the pseudo-physical map.  in xen_memory_setup()
845 		xen_e820_table.entries[xen_e820_table.nr_entries].size = IBFT_END - IBFT_START;  in xen_memory_setup()
851 	/* Make sure the Xen-supplied memory map is well-ordered. */  in xen_memory_setup()
855 	 * Check whether the kernel itself conflicts with the target E820 map.  in xen_memory_setup()
860 			       __pa_symbol(_end) - __pa_symbol(_text),  in xen_memory_setup()
864 	 * Check for a conflict of the xen_start_info memory with the target  in xen_memory_setup()
865 	 * E820 map.  in xen_memory_setup()
872 	 * the target E820 map.  in xen_memory_setup()
882 		extra_pages += max_pages - ini_nr_pages;  in xen_memory_setup()
885 	 * Clamp the amount of extra memory to a EXTRA_MEM_RATIO  in xen_memory_setup()
888 	 * Make sure we have no memory above max_pages, as this area  in xen_memory_setup()
892 	extra_pages = min3(maxmem_pages, extra_pages, max_pages - ini_nr_pages);  in xen_memory_setup()
907 				chunk_size = min(size, mem_end - addr);  in xen_memory_setup()
911 				n_pfns = PFN_DOWN(addr + chunk_size) - pfn_s;  in xen_memory_setup()
912 				extra_pages -= n_pfns;  in xen_memory_setup()
923 		size -= chunk_size;  in xen_memory_setup()
940 	 * In domU, the ISA region is normal, usable memory, but we  in xen_memory_setup()
941 	 * reserve ISA memory anyway because too many things poke  in xen_memory_setup()
944 	e820__range_add(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, E820_TYPE_RESERVED);  in xen_memory_setup()
950 	/* Check for a conflict of the initrd with the target E820 map. */  in xen_memory_setup()
957 			xen_raw_console_write("Can't find new memory area for initrd needed due to E820 map conflict\n");  in xen_memory_setup()
964 		pr_info("initrd moved from [mem %#010llx-%#010llx] to [mem %#010llx-%#010llx]\n",  in xen_memory_setup()
972 	 * Set identity map on non-RAM pages and prepare remapping the  in xen_memory_setup()
1007 		/* Pretty fatal; 64-bit userspace has no other  in xen_enable_syscall()
1036 	if (!(xen_start_info->flags & SIF_INITDOMAIN)) {  in xen_arch_setup()
1042 	memcpy(boot_command_line, xen_start_info->cmd_line,  in xen_arch_setup()