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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /fs/proc/consoles.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/proc/consoles.c')
-rw-r--r--fs/proc/consoles.c113
1 files changed, 113 insertions, 0 deletions
diff --git a/fs/proc/consoles.c b/fs/proc/consoles.c
new file mode 100644
index 0000000000..e0758fe793
--- /dev/null
+++ b/fs/proc/consoles.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2010 Werner Fink, Jiri Slaby
+ */
+
+#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;
+
+ /*
+ * Take console_lock to serialize device() callback with
+ * other console operations. For example, fg_console is
+ * modified under console_lock when switching vt.
+ */
+ console_lock();
+ driver = con->device(con, &index);
+ console_unlock();
+
+ 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_putc(m, '\n');
+ return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+ struct console *con;
+ loff_t off = 0;
+
+ /*
+ * Hold the console_list_lock to guarantee safe traversal of the
+ * console list. SRCU cannot be used because there is no
+ * place to store the SRCU cookie.
+ */
+ console_list_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 hlist_entry_safe(con->node.next, struct console, node);
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+ console_list_unlock();
+}
+
+static const struct seq_operations consoles_op = {
+ .start = c_start,
+ .next = c_next,
+ .stop = c_stop,
+ .show = show_console_dev
+};
+
+static int __init proc_consoles_init(void)
+{
+ proc_create_seq("consoles", 0, NULL, &consoles_op);
+ return 0;
+}
+fs_initcall(proc_consoles_init);