File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/fs/proc/consoles.c b/fs/proc/consoles.c
new file mode 100644
index 0000000..290ba85
--- /dev/null
+++ b/fs/proc/consoles.c
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2010 Werner Fink, Jiri Slaby
+ *
+ * Licensed under GPLv2
+ */
+
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/tty_driver.h>
+
+/*
+ * This is handler for /proc/consoles
+ */
+static int show_console_dev(struct seq_file *m, void *v)
+{
+ static const struct {
+ short flag;
+ char name;
+ } con_flags[] = {
+ { CON_ENABLED, 'E' },
+ { CON_CONSDEV, 'C' },
+ { CON_BOOT, 'B' },
+ { CON_PRINTBUFFER, 'p' },
+ { CON_BRL, 'b' },
+ { CON_ANYTIME, 'a' },
+ };
+ char flags[ARRAY_SIZE(con_flags) + 1];
+ struct console *con = v;
+ unsigned int a;
+ dev_t dev = 0;
+
+ if (con->device) {
+ const struct tty_driver *driver;
+ int index;
+ driver = con->device(con, &index);
+ if (driver) {
+ dev = MKDEV(driver->major, driver->minor_start);
+ dev += index;
+ }
+ }
+
+ for (a = 0; a < ARRAY_SIZE(con_flags); a++)
+ flags[a] = (con->flags & con_flags[a].flag) ?
+ con_flags[a].name : ' ';
+ flags[a] = 0;
+
+ seq_setwidth(m, 21 - 1);
+ seq_printf(m, "%s%d", con->name, con->index);
+ seq_pad(m, ' ');
+ seq_printf(m, "%c%c%c (%s)", con->read ? 'R' : '-',
+ con->write ? 'W' : '-', con->unblank ? 'U' : '-',
+ flags);
+ if (dev)
+ seq_printf(m, " %4d:%d", MAJOR(dev), MINOR(dev));
+
+ seq_printf(m, "\n");
+
+ return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+ struct console *con;
+ loff_t off = 0;
+
+ console_lock();
+ for_each_console(con)
+ if (off++ == *pos)
+ break;
+
+ return con;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct console *con = v;
+ ++*pos;
+ return con->next;
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+ console_unlock();
+}
+
+static const struct seq_operations consoles_op = {
+ .start = c_start,
+ .next = c_next,
+ .stop = c_stop,
+ .show = show_console_dev
+};
+
+static int consoles_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &consoles_op);
+}
+
+static const struct file_operations proc_consoles_operations = {
+ .open = consoles_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init proc_consoles_init(void)
+{
+ proc_create("consoles", 0, NULL, &proc_consoles_operations);
+ return 0;
+}
+fs_initcall(proc_consoles_init);