diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/arm64/mm/init.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm64/mm/init.c')
-rw-r--r-- | arch/arm64/mm/init.c | 694 |
1 files changed, 694 insertions, 0 deletions
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c new file mode 100644 index 000000000..29d2f4258 --- /dev/null +++ b/arch/arm64/mm/init.c @@ -0,0 +1,694 @@ +/* + * Based on arch/arm/mm/init.c + * + * Copyright (C) 1995-2005 Russell King + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/errno.h> +#include <linux/swap.h> +#include <linux/init.h> +#include <linux/bootmem.h> +#include <linux/cache.h> +#include <linux/mman.h> +#include <linux/nodemask.h> +#include <linux/initrd.h> +#include <linux/gfp.h> +#include <linux/memblock.h> +#include <linux/sort.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/dma-mapping.h> +#include <linux/dma-contiguous.h> +#include <linux/efi.h> +#include <linux/swiotlb.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> +#include <linux/kexec.h> +#include <linux/crash_dump.h> + +#include <asm/boot.h> +#include <asm/fixmap.h> +#include <asm/kasan.h> +#include <asm/kernel-pgtable.h> +#include <asm/memory.h> +#include <asm/numa.h> +#include <asm/sections.h> +#include <asm/setup.h> +#include <asm/sizes.h> +#include <asm/tlb.h> +#include <asm/alternative.h> + +/* + * We need to be able to catch inadvertent references to memstart_addr + * that occur (potentially in generic code) before arm64_memblock_init() + * executes, which assigns it its actual value. So use a default value + * that cannot be mistaken for a real physical address. + */ +s64 memstart_addr __ro_after_init = -1; +phys_addr_t arm64_dma_phys_limit __ro_after_init; + +#ifdef CONFIG_BLK_DEV_INITRD +static int __init early_initrd(char *p) +{ + unsigned long start, size; + char *endp; + + start = memparse(p, &endp); + if (*endp == ',') { + size = memparse(endp + 1, NULL); + + initrd_start = start; + initrd_end = start + size; + } + return 0; +} +early_param("initrd", early_initrd); +#endif + +#ifdef CONFIG_KEXEC_CORE +/* + * reserve_crashkernel() - reserves memory for crash kernel + * + * This function reserves memory area given in "crashkernel=" kernel command + * line parameter. The memory reserved is used by dump capture kernel when + * primary kernel is crashing. + */ +static void __init reserve_crashkernel(void) +{ + unsigned long long crash_base, crash_size; + int ret; + + ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), + &crash_size, &crash_base); + /* no crashkernel= or invalid value specified */ + if (ret || !crash_size) + return; + + crash_size = PAGE_ALIGN(crash_size); + + if (crash_base == 0) { + /* Current arm64 boot protocol requires 2MB alignment */ + crash_base = memblock_find_in_range(0, ARCH_LOW_ADDRESS_LIMIT, + crash_size, SZ_2M); + if (crash_base == 0) { + pr_warn("cannot allocate crashkernel (size:0x%llx)\n", + crash_size); + return; + } + } else { + /* User specifies base address explicitly. */ + if (!memblock_is_region_memory(crash_base, crash_size)) { + pr_warn("cannot reserve crashkernel: region is not memory\n"); + return; + } + + if (memblock_is_region_reserved(crash_base, crash_size)) { + pr_warn("cannot reserve crashkernel: region overlaps reserved memory\n"); + return; + } + + if (!IS_ALIGNED(crash_base, SZ_2M)) { + pr_warn("cannot reserve crashkernel: base address is not 2MB aligned\n"); + return; + } + } + memblock_reserve(crash_base, crash_size); + + pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", + crash_base, crash_base + crash_size, crash_size >> 20); + + crashk_res.start = crash_base; + crashk_res.end = crash_base + crash_size - 1; +} + +static void __init kexec_reserve_crashkres_pages(void) +{ +#ifdef CONFIG_HIBERNATION + phys_addr_t addr; + struct page *page; + + if (!crashk_res.end) + return; + + /* + * To reduce the size of hibernation image, all the pages are + * marked as Reserved initially. + */ + for (addr = crashk_res.start; addr < (crashk_res.end + 1); + addr += PAGE_SIZE) { + page = phys_to_page(addr); + SetPageReserved(page); + } +#endif +} +#else +static void __init reserve_crashkernel(void) +{ +} + +static void __init kexec_reserve_crashkres_pages(void) +{ +} +#endif /* CONFIG_KEXEC_CORE */ + +#ifdef CONFIG_CRASH_DUMP +static int __init early_init_dt_scan_elfcorehdr(unsigned long node, + const char *uname, int depth, void *data) +{ + const __be32 *reg; + int len; + + if (depth != 1 || strcmp(uname, "chosen") != 0) + return 0; + + reg = of_get_flat_dt_prop(node, "linux,elfcorehdr", &len); + if (!reg || (len < (dt_root_addr_cells + dt_root_size_cells))) + return 1; + + elfcorehdr_addr = dt_mem_next_cell(dt_root_addr_cells, ®); + elfcorehdr_size = dt_mem_next_cell(dt_root_size_cells, ®); + + return 1; +} + +/* + * reserve_elfcorehdr() - reserves memory for elf core header + * + * This function reserves the memory occupied by an elf core header + * described in the device tree. This region contains all the + * information about primary kernel's core image and is used by a dump + * capture kernel to access the system memory on primary kernel. + */ +static void __init reserve_elfcorehdr(void) +{ + of_scan_flat_dt(early_init_dt_scan_elfcorehdr, NULL); + + if (!elfcorehdr_size) + return; + + if (memblock_is_region_reserved(elfcorehdr_addr, elfcorehdr_size)) { + pr_warn("elfcorehdr is overlapped\n"); + return; + } + + memblock_reserve(elfcorehdr_addr, elfcorehdr_size); + + pr_info("Reserving %lldKB of memory at 0x%llx for elfcorehdr\n", + elfcorehdr_size >> 10, elfcorehdr_addr); +} +#else +static void __init reserve_elfcorehdr(void) +{ +} +#endif /* CONFIG_CRASH_DUMP */ +/* + * Return the maximum physical address for ZONE_DMA32 (DMA_BIT_MASK(32)). It + * currently assumes that for memory starting above 4G, 32-bit devices will + * use a DMA offset. + */ +static phys_addr_t __init max_zone_dma_phys(void) +{ + phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32); + return min(offset + (1ULL << 32), memblock_end_of_DRAM()); +} + +#ifdef CONFIG_NUMA + +static void __init zone_sizes_init(unsigned long min, unsigned long max) +{ + unsigned long max_zone_pfns[MAX_NR_ZONES] = {0}; + +#ifdef CONFIG_ZONE_DMA32 + max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys()); +#endif + max_zone_pfns[ZONE_NORMAL] = max; + + free_area_init_nodes(max_zone_pfns); +} + +#else + +static void __init zone_sizes_init(unsigned long min, unsigned long max) +{ + struct memblock_region *reg; + unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; + unsigned long max_dma = min; + + memset(zone_size, 0, sizeof(zone_size)); + + /* 4GB maximum for 32-bit only capable devices */ +#ifdef CONFIG_ZONE_DMA32 + max_dma = PFN_DOWN(arm64_dma_phys_limit); + zone_size[ZONE_DMA32] = max_dma - min; +#endif + zone_size[ZONE_NORMAL] = max - max_dma; + + memcpy(zhole_size, zone_size, sizeof(zhole_size)); + + for_each_memblock(memory, reg) { + unsigned long start = memblock_region_memory_base_pfn(reg); + unsigned long end = memblock_region_memory_end_pfn(reg); + + if (start >= max) + continue; + +#ifdef CONFIG_ZONE_DMA32 + if (start < max_dma) { + unsigned long dma_end = min(end, max_dma); + zhole_size[ZONE_DMA32] -= dma_end - start; + } +#endif + if (end > max_dma) { + unsigned long normal_end = min(end, max); + unsigned long normal_start = max(start, max_dma); + zhole_size[ZONE_NORMAL] -= normal_end - normal_start; + } + } + + free_area_init_node(0, zone_size, min, zhole_size); +} + +#endif /* CONFIG_NUMA */ + +#ifdef CONFIG_HAVE_ARCH_PFN_VALID +int pfn_valid(unsigned long pfn) +{ + phys_addr_t addr = pfn << PAGE_SHIFT; + + if ((addr >> PAGE_SHIFT) != pfn) + return 0; + return memblock_is_map_memory(addr); +} +EXPORT_SYMBOL(pfn_valid); +#endif + +#ifndef CONFIG_SPARSEMEM +static void __init arm64_memory_present(void) +{ +} +#else +static void __init arm64_memory_present(void) +{ + struct memblock_region *reg; + + for_each_memblock(memory, reg) { + int nid = memblock_get_region_node(reg); + + memory_present(nid, memblock_region_memory_base_pfn(reg), + memblock_region_memory_end_pfn(reg)); + } +} +#endif + +static phys_addr_t memory_limit = PHYS_ADDR_MAX; + +/* + * Limit the memory size that was specified via FDT. + */ +static int __init early_mem(char *p) +{ + if (!p) + return 1; + + memory_limit = memparse(p, &p) & PAGE_MASK; + pr_notice("Memory limited to %lldMB\n", memory_limit >> 20); + + return 0; +} +early_param("mem", early_mem); + +static int __init early_init_dt_scan_usablemem(unsigned long node, + const char *uname, int depth, void *data) +{ + struct memblock_region *usablemem = data; + const __be32 *reg; + int len; + + if (depth != 1 || strcmp(uname, "chosen") != 0) + return 0; + + reg = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len); + if (!reg || (len < (dt_root_addr_cells + dt_root_size_cells))) + return 1; + + usablemem->base = dt_mem_next_cell(dt_root_addr_cells, ®); + usablemem->size = dt_mem_next_cell(dt_root_size_cells, ®); + + return 1; +} + +static void __init fdt_enforce_memory_region(void) +{ + struct memblock_region reg = { + .size = 0, + }; + + of_scan_flat_dt(early_init_dt_scan_usablemem, ®); + + if (reg.size) + memblock_cap_memory_range(reg.base, reg.size); +} + +void __init arm64_memblock_init(void) +{ + const s64 linear_region_size = -(s64)PAGE_OFFSET; + + /* Handle linux,usable-memory-range property */ + fdt_enforce_memory_region(); + + /* Remove memory above our supported physical address size */ + memblock_remove(1ULL << PHYS_MASK_SHIFT, ULLONG_MAX); + + /* + * Ensure that the linear region takes up exactly half of the kernel + * virtual address space. This way, we can distinguish a linear address + * from a kernel/module/vmalloc address by testing a single bit. + */ + BUILD_BUG_ON(linear_region_size != BIT(VA_BITS - 1)); + + /* + * Select a suitable value for the base of physical memory. + */ + memstart_addr = round_down(memblock_start_of_DRAM(), + ARM64_MEMSTART_ALIGN); + + /* + * Remove the memory that we will not be able to cover with the + * linear mapping. Take care not to clip the kernel which may be + * high in memory. + */ + memblock_remove(max_t(u64, memstart_addr + linear_region_size, + __pa_symbol(_end)), ULLONG_MAX); + if (memstart_addr + linear_region_size < memblock_end_of_DRAM()) { + /* ensure that memstart_addr remains sufficiently aligned */ + memstart_addr = round_up(memblock_end_of_DRAM() - linear_region_size, + ARM64_MEMSTART_ALIGN); + memblock_remove(0, memstart_addr); + } + + /* + * Apply the memory limit if it was set. Since the kernel may be loaded + * high up in memory, add back the kernel region that must be accessible + * via the linear mapping. + */ + if (memory_limit != PHYS_ADDR_MAX) { + memblock_mem_limit_remove_map(memory_limit); + memblock_add(__pa_symbol(_text), (u64)(_end - _text)); + } + + if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && initrd_start) { + /* + * Add back the memory we just removed if it results in the + * initrd to become inaccessible via the linear mapping. + * Otherwise, this is a no-op + */ + u64 base = initrd_start & PAGE_MASK; + u64 size = PAGE_ALIGN(initrd_end) - base; + + /* + * We can only add back the initrd memory if we don't end up + * with more memory than we can address via the linear mapping. + * It is up to the bootloader to position the kernel and the + * initrd reasonably close to each other (i.e., within 32 GB of + * each other) so that all granule/#levels combinations can + * always access both. + */ + if (WARN(base < memblock_start_of_DRAM() || + base + size > memblock_start_of_DRAM() + + linear_region_size, + "initrd not fully accessible via the linear mapping -- please check your bootloader ...\n")) { + initrd_start = 0; + } else { + memblock_remove(base, size); /* clear MEMBLOCK_ flags */ + memblock_add(base, size); + memblock_reserve(base, size); + } + } + + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { + extern u16 memstart_offset_seed; + u64 range = linear_region_size - + (memblock_end_of_DRAM() - memblock_start_of_DRAM()); + + /* + * If the size of the linear region exceeds, by a sufficient + * margin, the size of the region that the available physical + * memory spans, randomize the linear region as well. + */ + if (memstart_offset_seed > 0 && range >= ARM64_MEMSTART_ALIGN) { + range /= ARM64_MEMSTART_ALIGN; + memstart_addr -= ARM64_MEMSTART_ALIGN * + ((range * memstart_offset_seed) >> 16); + } + } + + /* + * Register the kernel text, kernel data, initrd, and initial + * pagetables with memblock. + */ + memblock_reserve(__pa_symbol(_text), _end - _text); +#ifdef CONFIG_BLK_DEV_INITRD + if (initrd_start) { + memblock_reserve(initrd_start, initrd_end - initrd_start); + + /* the generic initrd code expects virtual addresses */ + initrd_start = __phys_to_virt(initrd_start); + initrd_end = __phys_to_virt(initrd_end); + } +#endif + + early_init_fdt_scan_reserved_mem(); + + /* 4GB maximum for 32-bit only capable devices */ + if (IS_ENABLED(CONFIG_ZONE_DMA32)) + arm64_dma_phys_limit = max_zone_dma_phys(); + else + arm64_dma_phys_limit = PHYS_MASK + 1; + + reserve_crashkernel(); + + reserve_elfcorehdr(); + + high_memory = __va(memblock_end_of_DRAM() - 1) + 1; + + dma_contiguous_reserve(arm64_dma_phys_limit); + + memblock_allow_resize(); +} + +void __init bootmem_init(void) +{ + unsigned long min, max; + + min = PFN_UP(memblock_start_of_DRAM()); + max = PFN_DOWN(memblock_end_of_DRAM()); + + early_memtest(min << PAGE_SHIFT, max << PAGE_SHIFT); + + max_pfn = max_low_pfn = max; + + arm64_numa_init(); + /* + * Sparsemem tries to allocate bootmem in memory_present(), so must be + * done after the fixed reservations. + */ + arm64_memory_present(); + + sparse_init(); + zone_sizes_init(min, max); + + memblock_dump_all(); +} + +#ifndef CONFIG_SPARSEMEM_VMEMMAP +static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn) +{ + struct page *start_pg, *end_pg; + unsigned long pg, pgend; + + /* + * Convert start_pfn/end_pfn to a struct page pointer. + */ + start_pg = pfn_to_page(start_pfn - 1) + 1; + end_pg = pfn_to_page(end_pfn - 1) + 1; + + /* + * Convert to physical addresses, and round start upwards and end + * downwards. + */ + pg = (unsigned long)PAGE_ALIGN(__pa(start_pg)); + pgend = (unsigned long)__pa(end_pg) & PAGE_MASK; + + /* + * If there are free pages between these, free the section of the + * memmap array. + */ + if (pg < pgend) + free_bootmem(pg, pgend - pg); +} + +/* + * The mem_map array can get very big. Free the unused area of the memory map. + */ +static void __init free_unused_memmap(void) +{ + unsigned long start, prev_end = 0; + struct memblock_region *reg; + + for_each_memblock(memory, reg) { + start = __phys_to_pfn(reg->base); + +#ifdef CONFIG_SPARSEMEM + /* + * Take care not to free memmap entries that don't exist due + * to SPARSEMEM sections which aren't present. + */ + start = min(start, ALIGN(prev_end, PAGES_PER_SECTION)); +#endif + /* + * If we had a previous bank, and there is a space between the + * current bank and the previous, free it. + */ + if (prev_end && prev_end < start) + free_memmap(prev_end, start); + + /* + * Align up here since the VM subsystem insists that the + * memmap entries are valid from the bank end aligned to + * MAX_ORDER_NR_PAGES. + */ + prev_end = ALIGN(__phys_to_pfn(reg->base + reg->size), + MAX_ORDER_NR_PAGES); + } + +#ifdef CONFIG_SPARSEMEM + if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) + free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION)); +#endif +} +#endif /* !CONFIG_SPARSEMEM_VMEMMAP */ + +/* + * mem_init() marks the free areas in the mem_map and tells us how much memory + * is free. This is done after various parts of the system have claimed their + * memory after the kernel image. + */ +void __init mem_init(void) +{ + if (swiotlb_force == SWIOTLB_FORCE || + max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT)) + swiotlb_init(1); + else + swiotlb_force = SWIOTLB_NO_FORCE; + + set_max_mapnr(pfn_to_page(max_pfn) - mem_map); + +#ifndef CONFIG_SPARSEMEM_VMEMMAP + free_unused_memmap(); +#endif + /* this will put all unused low memory onto the freelists */ + free_all_bootmem(); + + kexec_reserve_crashkres_pages(); + + mem_init_print_info(NULL); + + /* + * Check boundaries twice: Some fundamental inconsistencies can be + * detected at build time already. + */ +#ifdef CONFIG_COMPAT + BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64); +#endif + +#ifdef CONFIG_SPARSEMEM_VMEMMAP + /* + * Make sure we chose the upper bound of sizeof(struct page) + * correctly when sizing the VMEMMAP array. + */ + BUILD_BUG_ON(sizeof(struct page) > (1 << STRUCT_PAGE_MAX_SHIFT)); +#endif + + if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { + extern int sysctl_overcommit_memory; + /* + * On a machine this small we won't get anywhere without + * overcommit, so turn it on by default. + */ + sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; + } +} + +void free_initmem(void) +{ + free_reserved_area(lm_alias(__init_begin), + lm_alias(__init_end), + 0, "unused kernel"); + /* + * Unmap the __init region but leave the VM area in place. This + * prevents the region from being reused for kernel modules, which + * is not supported by kallsyms. + */ + unmap_kernel_range((u64)__init_begin, (u64)(__init_end - __init_begin)); +} + +#ifdef CONFIG_BLK_DEV_INITRD + +static int keep_initrd __initdata; + +void __init free_initrd_mem(unsigned long start, unsigned long end) +{ + if (!keep_initrd) { + free_reserved_area((void *)start, (void *)end, 0, "initrd"); + memblock_free(__virt_to_phys(start), end - start); + } +} + +static int __init keepinitrd_setup(char *__unused) +{ + keep_initrd = 1; + return 1; +} + +__setup("keepinitrd", keepinitrd_setup); +#endif + +/* + * Dump out memory limit information on panic. + */ +static int dump_mem_limit(struct notifier_block *self, unsigned long v, void *p) +{ + if (memory_limit != PHYS_ADDR_MAX) { + pr_emerg("Memory Limit: %llu MB\n", memory_limit >> 20); + } else { + pr_emerg("Memory Limit: none\n"); + } + return 0; +} + +static struct notifier_block mem_limit_notifier = { + .notifier_call = dump_mem_limit, +}; + +static int __init register_mem_limit_dumper(void) +{ + atomic_notifier_chain_register(&panic_notifier_list, + &mem_limit_notifier); + return 0; +} +__initcall(register_mem_limit_dumper); |