| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2010 Werner Fink, Jiri Slaby |
| 3 | * |
| 4 | * Licensed under GPLv2 |
| 5 | */ |
| 6 | |
| 7 | #include <linux/console.h> |
| 8 | #include <linux/kernel.h> |
| 9 | #include <linux/proc_fs.h> |
| 10 | #include <linux/seq_file.h> |
| 11 | #include <linux/tty_driver.h> |
| 12 | |
| 13 | /* |
| 14 | * This is handler for /proc/consoles |
| 15 | */ |
| 16 | static int show_console_dev(struct seq_file *m, void *v) |
| 17 | { |
| 18 | static const struct { |
| 19 | short flag; |
| 20 | char name; |
| 21 | } con_flags[] = { |
| 22 | { CON_ENABLED, 'E' }, |
| 23 | { CON_CONSDEV, 'C' }, |
| 24 | { CON_BOOT, 'B' }, |
| 25 | { CON_PRINTBUFFER, 'p' }, |
| 26 | { CON_BRL, 'b' }, |
| 27 | { CON_ANYTIME, 'a' }, |
| 28 | }; |
| 29 | char flags[ARRAY_SIZE(con_flags) + 1]; |
| 30 | struct console *con = v; |
| 31 | unsigned int a; |
| 32 | dev_t dev = 0; |
| 33 | |
| 34 | if (con->device) { |
| 35 | const struct tty_driver *driver; |
| 36 | int index; |
| 37 | driver = con->device(con, &index); |
| 38 | if (driver) { |
| 39 | dev = MKDEV(driver->major, driver->minor_start); |
| 40 | dev += index; |
| 41 | } |
| 42 | } |
| 43 | |
| 44 | for (a = 0; a < ARRAY_SIZE(con_flags); a++) |
| 45 | flags[a] = (con->flags & con_flags[a].flag) ? |
| 46 | con_flags[a].name : ' '; |
| 47 | flags[a] = 0; |
| 48 | |
| 49 | seq_setwidth(m, 21 - 1); |
| 50 | seq_printf(m, "%s%d", con->name, con->index); |
| 51 | seq_pad(m, ' '); |
| 52 | seq_printf(m, "%c%c%c (%s)", con->read ? 'R' : '-', |
| 53 | con->write ? 'W' : '-', con->unblank ? 'U' : '-', |
| 54 | flags); |
| 55 | if (dev) |
| 56 | seq_printf(m, " %4d:%d", MAJOR(dev), MINOR(dev)); |
| 57 | |
| 58 | seq_putc(m, '\n'); |
| 59 | return 0; |
| 60 | } |
| 61 | |
| 62 | static void *c_start(struct seq_file *m, loff_t *pos) |
| 63 | { |
| 64 | struct console *con; |
| 65 | loff_t off = 0; |
| 66 | |
| 67 | console_lock(); |
| 68 | for_each_console(con) |
| 69 | if (off++ == *pos) |
| 70 | break; |
| 71 | |
| 72 | return con; |
| 73 | } |
| 74 | |
| 75 | static void *c_next(struct seq_file *m, void *v, loff_t *pos) |
| 76 | { |
| 77 | struct console *con = v; |
| 78 | ++*pos; |
| 79 | return con->next; |
| 80 | } |
| 81 | |
| 82 | static void c_stop(struct seq_file *m, void *v) |
| 83 | { |
| 84 | console_unlock(); |
| 85 | } |
| 86 | |
| 87 | static const struct seq_operations consoles_op = { |
| 88 | .start = c_start, |
| 89 | .next = c_next, |
| 90 | .stop = c_stop, |
| 91 | .show = show_console_dev |
| 92 | }; |
| 93 | |
| 94 | static int __init proc_consoles_init(void) |
| 95 | { |
| 96 | if (IS_ENABLED(CONFIG_PROC_STRIPPED)) |
| 97 | return 0; |
| 98 | |
| 99 | proc_create_seq("consoles", 0, NULL, &consoles_op); |
| 100 | return 0; |
| 101 | } |
| 102 | fs_initcall(proc_consoles_init); |