mirror of https://gitee.com/openkylin/linux.git
64 lines
1.7 KiB
C
64 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/console.h>
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#include "chan_user.h"
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/* ----------------------------------------------------------------------------- */
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/* trivial console driver -- simply dump everything to stderr */
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/*
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* Don't register by default -- as this registers very early in the
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* boot process it becomes the default console.
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*
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* Initialized at init time.
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*/
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static int use_stderr_console = 0;
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static void stderr_console_write(struct console *console, const char *string,
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unsigned len)
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{
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generic_write(2 /* stderr */, string, len, NULL);
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}
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static struct console stderr_console = {
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.name = "stderr",
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.write = stderr_console_write,
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.flags = CON_PRINTBUFFER,
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};
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static int __init stderr_console_init(void)
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{
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if (use_stderr_console)
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register_console(&stderr_console);
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return 0;
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}
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console_initcall(stderr_console_init);
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static int stderr_setup(char *str)
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{
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if (!str)
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return 0;
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use_stderr_console = simple_strtoul(str,&str,0);
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return 1;
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}
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__setup("stderr=", stderr_setup);
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/* The previous behavior of not unregistering led to /dev/console being
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* impossible to open. My FC5 filesystem started having init die, and the
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* system panicing because of this. Unregistering causes the real
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* console to become the default console, and /dev/console can then be
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* opened. Making this an initcall makes this happen late enough that
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* there is no added value in dumping everything to stderr, and the
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* normal console is good enough to show you all available output.
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*/
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static int __init unregister_stderr(void)
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{
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unregister_console(&stderr_console);
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return 0;
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}
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__initcall(unregister_stderr);
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