crash: split vmcoreinfo exporting code out from crash_core.c

Now move the relevant codes into separate files:
kernel/crash_reserve.c, include/linux/crash_reserve.h.

And add config item CRASH_RESERVE to control its enabling.

And also update the old ifdeffery of CONFIG_CRASH_CORE, including of
<linux/crash_core.h> and config item dependency on CRASH_CORE
accordingly.

And also do renaming as follows:
 - arch/xxx/kernel/{crash_core.c => vmcore_info.c}
because they are only related to vmcoreinfo exporting on x86, arm64,
riscv.

And also Remove config item CRASH_CORE, and rely on CONFIG_KEXEC_CORE to
decide if build in crash_core.c.

[yang.lee@linux.alibaba.com: remove duplicated include in vmcore_info.c]
  Link: https://lkml.kernel.org/r/20240126005744.16561-1-yang.lee@linux.alibaba.com
Link: https://lkml.kernel.org/r/20240124051254.67105-3-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Pingfan Liu <piliu@redhat.com>
Cc: Klara Modin <klarasmodin@gmail.com>
Cc: Michael Kelley <mhklinux@outlook.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 0 insertions, 206 deletions

diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index ae0d1ce89b46b..2f4df1fe6f7af 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -26,14 +26,6 @@
 /* Per cpu memory for storing cpu states in case of system crash. */
 note_buf_t __percpu *crash_notes;
 
-/* vmcoreinfo stuff */
-unsigned char *vmcoreinfo_data;
-size_t vmcoreinfo_size;
-u32 *vmcoreinfo_note;
-
-/* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */
-static unsigned char *vmcoreinfo_data_safecopy;
-
 int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
 			  void **addr, unsigned long *sz)
 {
@@ -195,204 +187,6 @@ int crash_exclude_mem_range(struct crash_mem *mem,
 	return 0;
 }
 
-Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
-			  void *data, size_t data_len)
-{
-	struct elf_note *note = (struct elf_note *)buf;
-
-	note->n_namesz = strlen(name) + 1;
-	note->n_descsz = data_len;
-	note->n_type   = type;
-	buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf_Word));
-	memcpy(buf, name, note->n_namesz);
-	buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf_Word));
-	memcpy(buf, data, data_len);
-	buf += DIV_ROUND_UP(data_len, sizeof(Elf_Word));
-
-	return buf;
-}
-
-void final_note(Elf_Word *buf)
-{
-	memset(buf, 0, sizeof(struct elf_note));
-}
-
-static void update_vmcoreinfo_note(void)
-{
-	u32 *buf = vmcoreinfo_note;
-
-	if (!vmcoreinfo_size)
-		return;
-	buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
-			      vmcoreinfo_size);
-	final_note(buf);
-}
-
-void crash_update_vmcoreinfo_safecopy(void *ptr)
-{
-	if (ptr)
-		memcpy(ptr, vmcoreinfo_data, vmcoreinfo_size);
-
-	vmcoreinfo_data_safecopy = ptr;
-}
-
-void crash_save_vmcoreinfo(void)
-{
-	if (!vmcoreinfo_note)
-		return;
-
-	/* Use the safe copy to generate vmcoreinfo note if have */
-	if (vmcoreinfo_data_safecopy)
-		vmcoreinfo_data = vmcoreinfo_data_safecopy;
-
-	vmcoreinfo_append_str("CRASHTIME=%lld\n", ktime_get_real_seconds());
-	update_vmcoreinfo_note();
-}
-
-void vmcoreinfo_append_str(const char *fmt, ...)
-{
-	va_list args;
-	char buf[0x50];
-	size_t r;
-
-	va_start(args, fmt);
-	r = vscnprintf(buf, sizeof(buf), fmt, args);
-	va_end(args);
-
-	r = min(r, (size_t)VMCOREINFO_BYTES - vmcoreinfo_size);
-
-	memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
-
-	vmcoreinfo_size += r;
-
-	WARN_ONCE(vmcoreinfo_size == VMCOREINFO_BYTES,
-		  "vmcoreinfo data exceeds allocated size, truncating");
-}
-
-/*
- * provide an empty default implementation here -- architecture
- * code may override this
- */
-void __weak arch_crash_save_vmcoreinfo(void)
-{}
-
-phys_addr_t __weak paddr_vmcoreinfo_note(void)
-{
-	return __pa(vmcoreinfo_note);
-}
-EXPORT_SYMBOL(paddr_vmcoreinfo_note);
-
-static int __init crash_save_vmcoreinfo_init(void)
-{
-	vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL);
-	if (!vmcoreinfo_data) {
-		pr_warn("Memory allocation for vmcoreinfo_data failed\n");
-		return -ENOMEM;
-	}
-
-	vmcoreinfo_note = alloc_pages_exact(VMCOREINFO_NOTE_SIZE,
-						GFP_KERNEL | __GFP_ZERO);
-	if (!vmcoreinfo_note) {
-		free_page((unsigned long)vmcoreinfo_data);
-		vmcoreinfo_data = NULL;
-		pr_warn("Memory allocation for vmcoreinfo_note failed\n");
-		return -ENOMEM;
-	}
-
-	VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
-	VMCOREINFO_BUILD_ID();
-	VMCOREINFO_PAGESIZE(PAGE_SIZE);
-
-	VMCOREINFO_SYMBOL(init_uts_ns);
-	VMCOREINFO_OFFSET(uts_namespace, name);
-	VMCOREINFO_SYMBOL(node_online_map);
-#ifdef CONFIG_MMU
-	VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
-#endif
-	VMCOREINFO_SYMBOL(_stext);
-	vmcoreinfo_append_str("NUMBER(VMALLOC_START)=0x%lx\n", (unsigned long) VMALLOC_START);
-
-#ifndef CONFIG_NUMA
-	VMCOREINFO_SYMBOL(mem_map);
-	VMCOREINFO_SYMBOL(contig_page_data);
-#endif
-#ifdef CONFIG_SPARSEMEM
-	VMCOREINFO_SYMBOL_ARRAY(mem_section);
-	VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
-	VMCOREINFO_STRUCT_SIZE(mem_section);
-	VMCOREINFO_OFFSET(mem_section, section_mem_map);
-	VMCOREINFO_NUMBER(SECTION_SIZE_BITS);
-	VMCOREINFO_NUMBER(MAX_PHYSMEM_BITS);
-#endif
-	VMCOREINFO_STRUCT_SIZE(page);
-	VMCOREINFO_STRUCT_SIZE(pglist_data);
-	VMCOREINFO_STRUCT_SIZE(zone);
-	VMCOREINFO_STRUCT_SIZE(free_area);
-	VMCOREINFO_STRUCT_SIZE(list_head);
-	VMCOREINFO_SIZE(nodemask_t);
-	VMCOREINFO_OFFSET(page, flags);
-	VMCOREINFO_OFFSET(page, _refcount);
-	VMCOREINFO_OFFSET(page, mapping);
-	VMCOREINFO_OFFSET(page, lru);
-	VMCOREINFO_OFFSET(page, _mapcount);
-	VMCOREINFO_OFFSET(page, private);
-	VMCOREINFO_OFFSET(page, compound_head);
-	VMCOREINFO_OFFSET(pglist_data, node_zones);
-	VMCOREINFO_OFFSET(pglist_data, nr_zones);
-#ifdef CONFIG_FLATMEM
-	VMCOREINFO_OFFSET(pglist_data, node_mem_map);
-#endif
-	VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
-	VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
-	VMCOREINFO_OFFSET(pglist_data, node_id);
-	VMCOREINFO_OFFSET(zone, free_area);
-	VMCOREINFO_OFFSET(zone, vm_stat);
-	VMCOREINFO_OFFSET(zone, spanned_pages);
-	VMCOREINFO_OFFSET(free_area, free_list);
-	VMCOREINFO_OFFSET(list_head, next);
-	VMCOREINFO_OFFSET(list_head, prev);
-	VMCOREINFO_LENGTH(zone.free_area, NR_PAGE_ORDERS);
-	log_buf_vmcoreinfo_setup();
-	VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
-	VMCOREINFO_NUMBER(NR_FREE_PAGES);
-	VMCOREINFO_NUMBER(PG_lru);
-	VMCOREINFO_NUMBER(PG_private);
-	VMCOREINFO_NUMBER(PG_swapcache);
-	VMCOREINFO_NUMBER(PG_swapbacked);
-	VMCOREINFO_NUMBER(PG_slab);
-#ifdef CONFIG_MEMORY_FAILURE
-	VMCOREINFO_NUMBER(PG_hwpoison);
-#endif
-	VMCOREINFO_NUMBER(PG_head_mask);
-#define PAGE_BUDDY_MAPCOUNT_VALUE	(~PG_buddy)
-	VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
-#ifdef CONFIG_HUGETLB_PAGE
-	VMCOREINFO_NUMBER(PG_hugetlb);
-#define PAGE_OFFLINE_MAPCOUNT_VALUE	(~PG_offline)
-	VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE);
-#endif
-
-#ifdef CONFIG_KALLSYMS
-	VMCOREINFO_SYMBOL(kallsyms_names);
-	VMCOREINFO_SYMBOL(kallsyms_num_syms);
-	VMCOREINFO_SYMBOL(kallsyms_token_table);
-	VMCOREINFO_SYMBOL(kallsyms_token_index);
-#ifdef CONFIG_KALLSYMS_BASE_RELATIVE
-	VMCOREINFO_SYMBOL(kallsyms_offsets);
-	VMCOREINFO_SYMBOL(kallsyms_relative_base);
-#else
-	VMCOREINFO_SYMBOL(kallsyms_addresses);
-#endif /* CONFIG_KALLSYMS_BASE_RELATIVE */
-#endif /* CONFIG_KALLSYMS */
-
-	arch_crash_save_vmcoreinfo();
-	update_vmcoreinfo_note();
-
-	return 0;
-}
-
-subsys_initcall(crash_save_vmcoreinfo_init);
-
 static int __init crash_notes_memory_init(void)
 {
 	/* Allocate memory for saving cpu registers. */