// SPDX-License-Identifier: GPL-2.0 #include #include #include #include #include #include #include #include #include #include #include #include "boot.h" int boot_console_loglevel = CONFIG_CONSOLE_LOGLEVEL_DEFAULT; bool boot_ignore_loglevel; char __bootdata(boot_rb)[PAGE_SIZE * 2]; bool __bootdata(boot_earlyprintk); size_t __bootdata(boot_rb_off); char __bootdata(bootdebug_filter)[128]; bool __bootdata(bootdebug); static void boot_rb_add(const char *str, size_t len) { /* leave double '\0' in the end */ size_t avail = sizeof(boot_rb) - boot_rb_off - 1; /* store strings separated by '\0' */ if (len + 1 > avail) boot_rb_off = 0; strcpy(boot_rb + boot_rb_off, str); boot_rb_off += len + 1; } static void print_rb_entry(const char *str) { sclp_early_printk(printk_skip_level(str)); } static bool debug_messages_printed(void) { return boot_earlyprintk && (boot_ignore_loglevel || boot_console_loglevel > LOGLEVEL_DEBUG); } void boot_rb_dump(void) { if (debug_messages_printed()) return; sclp_early_printk("Boot messages ring buffer:\n"); boot_rb_foreach(print_rb_entry); } const char hex_asc[] = "0123456789abcdef"; static char *as_hex(char *dst, unsigned long val, int pad) { char *p = dst + max(pad, (int)__fls(val | 1) / 4 + 1); for (*p-- = '\0'; p >= dst; val >>= 4) *p-- = hex_asc[val & 0x0f]; return dst; } #define MAX_NUMLEN 21 static char *as_dec(char *buf, unsigned long val, bool is_signed) { bool negative = false; char *p = buf + MAX_NUMLEN; if (is_signed && (long)val < 0) { val = (val == LONG_MIN ? LONG_MIN : -(long)val); negative = true; } *--p = '\0'; do { *--p = '0' + (val % 10); val /= 10; } while (val); if (negative) *--p = '-'; return p; } static ssize_t strpad(char *dst, size_t dst_size, const char *src, int _pad, bool zero_pad, bool decimal) { ssize_t len = strlen(src), pad = _pad; char *p = dst; if (max(len, abs(pad)) >= dst_size) return -E2BIG; if (pad > len) { if (decimal && zero_pad && *src == '-') { *p++ = '-'; src++; len--; pad--; } memset(p, zero_pad ? '0' : ' ', pad - len); p += pad - len; } memcpy(p, src, len); p += len; if (pad < 0 && -pad > len) { memset(p, ' ', -pad - len); p += -pad - len; } *p = '\0'; return p - dst; } static char *symstart(char *p) { while (*p) p--; return p + 1; } static noinline char *findsym(unsigned long ip, unsigned short *off, unsigned short *len) { /* symbol entries are in a form "10000 c4 startup\0" */ char *a = _decompressor_syms_start; char *b = _decompressor_syms_end; unsigned long start; unsigned long size; char *pivot; char *endp; while (a < b) { pivot = symstart(a + (b - a) / 2); start = simple_strtoull(pivot, &endp, 16); size = simple_strtoull(endp + 1, &endp, 16); if (ip < start) { b = pivot; continue; } if (ip > start + size) { a = pivot + strlen(pivot) + 1; continue; } *off = ip - start; *len = size; return endp + 1; } return NULL; } #define MAX_SYMLEN 64 static noinline char *strsym(char *buf, void *ip) { unsigned short off; unsigned short len; char *p; p = findsym((unsigned long)ip, &off, &len); if (p) { strncpy(buf, p, MAX_SYMLEN); /* reserve 15 bytes for offset/len in symbol+0x1234/0x1234 */ p = buf + strnlen(buf, MAX_SYMLEN - 15); strcpy(p, "+0x"); as_hex(p + 3, off, 0); strcat(p, "/0x"); as_hex(p + strlen(p), len, 0); } else { as_hex(buf, (unsigned long)ip, 16); } return buf; } static inline int printk_loglevel(const char *buf) { if (buf[0] == KERN_SOH_ASCII && buf[1]) { switch (buf[1]) { case '0' ... '7': return buf[1] - '0'; } } return MESSAGE_LOGLEVEL_DEFAULT; } static void boot_console_earlyprintk(const char *buf) { int level = printk_loglevel(buf); /* always print emergency messages */ if (level > LOGLEVEL_EMERG && !boot_earlyprintk) return; buf = printk_skip_level(buf); /* print debug messages only when bootdebug is enabled */ if (level == LOGLEVEL_DEBUG && (!bootdebug || !bootdebug_filter_match(skip_timestamp(buf)))) return; if (boot_ignore_loglevel || level < boot_console_loglevel) sclp_early_printk(buf); } static char *add_timestamp(char *buf) { #ifdef CONFIG_PRINTK_TIME union tod_clock *boot_clock = (union tod_clock *)&get_lowcore()->boot_clock; unsigned long ns = tod_to_ns(get_tod_clock() - boot_clock->tod); char ts[MAX_NUMLEN]; *buf++ = '['; buf += strpad(buf, MAX_NUMLEN, as_dec(ts, ns / NSEC_PER_SEC, 0), 5, 0, 0); *buf++ = '.'; buf += strpad(buf, MAX_NUMLEN, as_dec(ts, (ns % NSEC_PER_SEC) / NSEC_PER_USEC, 0), 6, 1, 0); *buf++ = ']'; *buf++ = ' '; #endif return buf; } #define va_arg_len_type(args, lenmod, typemod) \ ((lenmod == 'l') ? va_arg(args, typemod long) : \ (lenmod == 'h') ? (typemod short)va_arg(args, typemod int) : \ (lenmod == 'H') ? (typemod char)va_arg(args, typemod int) : \ (lenmod == 'z') ? va_arg(args, typemod long) : \ va_arg(args, typemod int)) int boot_printk(const char *fmt, ...) { char buf[1024] = { 0 }; char *end = buf + sizeof(buf) - 1; /* make sure buf is 0 terminated */ bool zero_pad, decimal; char *strval, *p = buf; char valbuf[MAX(MAX_SYMLEN, MAX_NUMLEN)]; va_list args; char lenmod; ssize_t len; int pad; *p++ = KERN_SOH_ASCII; *p++ = printk_get_level(fmt) ?: '0' + MESSAGE_LOGLEVEL_DEFAULT; p = add_timestamp(p); fmt = printk_skip_level(fmt); va_start(args, fmt); for (; p < end && *fmt; fmt++) { if (*fmt != '%') { *p++ = *fmt; continue; } if (*++fmt == '%') { *p++ = '%'; continue; } zero_pad = (*fmt == '0'); pad = simple_strtol(fmt, (char **)&fmt, 10); lenmod = (*fmt == 'h' || *fmt == 'l' || *fmt == 'z') ? *fmt++ : 0; if (lenmod == 'h' && *fmt == 'h') { lenmod = 'H'; fmt++; } decimal = false; switch (*fmt) { case 's': if (lenmod) goto out; strval = va_arg(args, char *); zero_pad = false; break; case 'p': if (*++fmt != 'S' || lenmod) goto out; strval = strsym(valbuf, va_arg(args, void *)); zero_pad = false; break; case 'd': case 'i': strval = as_dec(valbuf, va_arg_len_type(args, lenmod, signed), 1); decimal = true; break; case 'u': strval = as_dec(valbuf, va_arg_len_type(args, lenmod, unsigned), 0); break; case 'x': strval = as_hex(valbuf, va_arg_len_type(args, lenmod, unsigned), 0); break; default: goto out; } len = strpad(p, end - p, strval, pad, zero_pad, decimal); if (len == -E2BIG) break; p += len; } out: va_end(args); len = strlen(buf); if (len) { boot_rb_add(buf, len); boot_console_earlyprintk(buf); } return len; }