android_kernel_xiaomi_sm8350/include/linux/init.h
Alon Bar-Lev 30d7e0d466 [PATCH] Dynamic kernel command-line: common
Current implementation stores a static command-line buffer allocated to
COMMAND_LINE_SIZE size.  Most architectures stores two copies of this buffer,
one for future reference and one for parameter parsing.

Current kernel command-line size for most architecture is much too small for
module parameters, video settings, initramfs paramters and much more.  The
problem is that setting COMMAND_LINE_SIZE to a grater value, allocates static
buffers.

In order to allow a greater command-line size, these buffers should be
dynamically allocated or marked as init disposable buffers, so unused memory
can be released.

This patch renames the static saved_command_line variable into
boot_command_line adding __initdata attribute, so that it can be disposed
after initialization.  This rename is required so applications that use
saved_command_line will not be affected by this change.

It reintroduces saved_command_line as dynamically allocated buffer to match
the data in boot_command_line.

It also mark secondary command-line buffer as __initdata, and copies it to
dynamically allocated static_command_line buffer components may hold reference
to it after initialization.

This patch is for linux-2.6.20-rc4-mm1 and is divided to target each
architecture.  I could not check this in any architecture so please forgive me
if I got it wrong.

The per-architecture modification is very simple, use boot_command_line in
place of saved_command_line.  The common code is the change into dynamic
command-line.

This patch:

1. Rename saved_command_line into boot_command_line, mark as init
   disposable.

2. Add dynamic allocated saved_command_line.

3. Add dynamic allocated static_command_line.

4. During startup copy: boot_command_line into saved_command_line.  arch
   command_line into static_command_line.

5. Parse static_command_line and not arch command_line, so arch
   command_line may be freed.

Signed-off-by: Alon Bar-Lev <alon.barlev@gmail.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Chris Zankel <chris@zankel.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:37 -08:00

300 lines
9.4 KiB
C

#ifndef _LINUX_INIT_H
#define _LINUX_INIT_H
#include <linux/compiler.h>
/* These macros are used to mark some functions or
* initialized data (doesn't apply to uninitialized data)
* as `initialization' functions. The kernel can take this
* as hint that the function is used only during the initialization
* phase and free up used memory resources after
*
* Usage:
* For functions:
*
* You should add __init immediately before the function name, like:
*
* static void __init initme(int x, int y)
* {
* extern int z; z = x * y;
* }
*
* If the function has a prototype somewhere, you can also add
* __init between closing brace of the prototype and semicolon:
*
* extern int initialize_foobar_device(int, int, int) __init;
*
* For initialized data:
* You should insert __initdata between the variable name and equal
* sign followed by value, e.g.:
*
* static int init_variable __initdata = 0;
* static char linux_logo[] __initdata = { 0x32, 0x36, ... };
*
* Don't forget to initialize data not at file scope, i.e. within a function,
* as gcc otherwise puts the data into the bss section and not into the init
* section.
*
* Also note, that this data cannot be "const".
*/
/* These are for everybody (although not all archs will actually
discard it in modules) */
#define __init __attribute__ ((__section__ (".init.text")))
#define __initdata __attribute__ ((__section__ (".init.data")))
#define __exitdata __attribute__ ((__section__(".exit.data")))
#define __exit_call __attribute_used__ __attribute__ ((__section__ (".exitcall.exit")))
#ifdef MODULE
#define __exit __attribute__ ((__section__(".exit.text")))
#else
#define __exit __attribute_used__ __attribute__ ((__section__(".exit.text")))
#endif
/* For assembly routines */
#define __INIT .section ".init.text","ax"
#define __FINIT .previous
#define __INITDATA .section ".init.data","aw"
#ifndef __ASSEMBLY__
/*
* Used for initialization calls..
*/
typedef int (*initcall_t)(void);
typedef void (*exitcall_t)(void);
extern initcall_t __con_initcall_start[], __con_initcall_end[];
extern initcall_t __security_initcall_start[], __security_initcall_end[];
/* Defined in init/main.c */
extern char __initdata boot_command_line[];
extern char *saved_command_line;
extern unsigned int reset_devices;
/* used by init/main.c */
extern void setup_arch(char **);
#endif
#ifndef MODULE
#ifndef __ASSEMBLY__
/* initcalls are now grouped by functionality into separate
* subsections. Ordering inside the subsections is determined
* by link order.
* For backwards compatibility, initcall() puts the call in
* the device init subsection.
*
* The `id' arg to __define_initcall() is needed so that multiple initcalls
* can point at the same handler without causing duplicate-symbol build errors.
*/
#define __define_initcall(level,fn,id) \
static initcall_t __initcall_##fn##id __attribute_used__ \
__attribute__((__section__(".initcall" level ".init"))) = fn
/*
* A "pure" initcall has no dependencies on anything else, and purely
* initializes variables that couldn't be statically initialized.
*
* This only exists for built-in code, not for modules.
*/
#define pure_initcall(fn) __define_initcall("0",fn,1)
#define core_initcall(fn) __define_initcall("1",fn,1)
#define core_initcall_sync(fn) __define_initcall("1s",fn,1s)
#define postcore_initcall(fn) __define_initcall("2",fn,2)
#define postcore_initcall_sync(fn) __define_initcall("2s",fn,2s)
#define arch_initcall(fn) __define_initcall("3",fn,3)
#define arch_initcall_sync(fn) __define_initcall("3s",fn,3s)
#define subsys_initcall(fn) __define_initcall("4",fn,4)
#define subsys_initcall_sync(fn) __define_initcall("4s",fn,4s)
#define fs_initcall(fn) __define_initcall("5",fn,5)
#define fs_initcall_sync(fn) __define_initcall("5s",fn,5s)
#define rootfs_initcall(fn) __define_initcall("rootfs",fn,rootfs)
#define device_initcall(fn) __define_initcall("6",fn,6)
#define device_initcall_sync(fn) __define_initcall("6s",fn,6s)
#define late_initcall(fn) __define_initcall("7",fn,7)
#define late_initcall_sync(fn) __define_initcall("7s",fn,7s)
#define __initcall(fn) device_initcall(fn)
#define __exitcall(fn) \
static exitcall_t __exitcall_##fn __exit_call = fn
#define console_initcall(fn) \
static initcall_t __initcall_##fn \
__attribute_used__ __attribute__((__section__(".con_initcall.init")))=fn
#define security_initcall(fn) \
static initcall_t __initcall_##fn \
__attribute_used__ __attribute__((__section__(".security_initcall.init"))) = fn
struct obs_kernel_param {
const char *str;
int (*setup_func)(char *);
int early;
};
/*
* Only for really core code. See moduleparam.h for the normal way.
*
* Force the alignment so the compiler doesn't space elements of the
* obs_kernel_param "array" too far apart in .init.setup.
*/
#define __setup_param(str, unique_id, fn, early) \
static char __setup_str_##unique_id[] __initdata = str; \
static struct obs_kernel_param __setup_##unique_id \
__attribute_used__ \
__attribute__((__section__(".init.setup"))) \
__attribute__((aligned((sizeof(long))))) \
= { __setup_str_##unique_id, fn, early }
#define __setup_null_param(str, unique_id) \
__setup_param(str, unique_id, NULL, 0)
#define __setup(str, fn) \
__setup_param(str, fn, fn, 0)
#define __obsolete_setup(str) \
__setup_null_param(str, __LINE__)
/* NOTE: fn is as per module_param, not __setup! Emits warning if fn
* returns non-zero. */
#define early_param(str, fn) \
__setup_param(str, fn, fn, 1)
/* Relies on boot_command_line being set */
void __init parse_early_param(void);
#endif /* __ASSEMBLY__ */
/**
* module_init() - driver initialization entry point
* @x: function to be run at kernel boot time or module insertion
*
* module_init() will either be called during do_initcalls() (if
* builtin) or at module insertion time (if a module). There can only
* be one per module.
*/
#define module_init(x) __initcall(x);
/**
* module_exit() - driver exit entry point
* @x: function to be run when driver is removed
*
* module_exit() will wrap the driver clean-up code
* with cleanup_module() when used with rmmod when
* the driver is a module. If the driver is statically
* compiled into the kernel, module_exit() has no effect.
* There can only be one per module.
*/
#define module_exit(x) __exitcall(x);
#else /* MODULE */
/* Don't use these in modules, but some people do... */
#define core_initcall(fn) module_init(fn)
#define postcore_initcall(fn) module_init(fn)
#define arch_initcall(fn) module_init(fn)
#define subsys_initcall(fn) module_init(fn)
#define fs_initcall(fn) module_init(fn)
#define device_initcall(fn) module_init(fn)
#define late_initcall(fn) module_init(fn)
#define security_initcall(fn) module_init(fn)
/* These macros create a dummy inline: gcc 2.9x does not count alias
as usage, hence the `unused function' warning when __init functions
are declared static. We use the dummy __*_module_inline functions
both to kill the warning and check the type of the init/cleanup
function. */
/* Each module must use one module_init(), or one no_module_init */
#define module_init(initfn) \
static inline initcall_t __inittest(void) \
{ return initfn; } \
int init_module(void) __attribute__((alias(#initfn)));
/* This is only required if you want to be unloadable. */
#define module_exit(exitfn) \
static inline exitcall_t __exittest(void) \
{ return exitfn; } \
void cleanup_module(void) __attribute__((alias(#exitfn)));
#define __setup_param(str, unique_id, fn) /* nothing */
#define __setup_null_param(str, unique_id) /* nothing */
#define __setup(str, func) /* nothing */
#define __obsolete_setup(str) /* nothing */
#endif
/* Data marked not to be saved by software_suspend() */
#define __nosavedata __attribute__ ((__section__ (".data.nosave")))
/* This means "can be init if no module support, otherwise module load
may call it." */
#ifdef CONFIG_MODULES
#define __init_or_module
#define __initdata_or_module
#else
#define __init_or_module __init
#define __initdata_or_module __initdata
#endif /*CONFIG_MODULES*/
#ifdef CONFIG_HOTPLUG
#define __devinit
#define __devinitdata
#define __devexit
#define __devexitdata
#else
#define __devinit __init
#define __devinitdata __initdata
#define __devexit __exit
#define __devexitdata __exitdata
#endif
#ifdef CONFIG_HOTPLUG_CPU
#define __cpuinit
#define __cpuinitdata
#define __cpuexit
#define __cpuexitdata
#else
#define __cpuinit __init
#define __cpuinitdata __initdata
#define __cpuexit __exit
#define __cpuexitdata __exitdata
#endif
#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
|| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
#define __meminit
#define __meminitdata
#define __memexit
#define __memexitdata
#else
#define __meminit __init
#define __meminitdata __initdata
#define __memexit __exit
#define __memexitdata __exitdata
#endif
/* Functions marked as __devexit may be discarded at kernel link time, depending
on config options. Newer versions of binutils detect references from
retained sections to discarded sections and flag an error. Pointers to
__devexit functions must use __devexit_p(function_name), the wrapper will
insert either the function_name or NULL, depending on the config options.
*/
#if defined(MODULE) || defined(CONFIG_HOTPLUG)
#define __devexit_p(x) x
#else
#define __devexit_p(x) NULL
#endif
#ifdef MODULE
#define __exit_p(x) x
#else
#define __exit_p(x) NULL
#endif
#endif /* _LINUX_INIT_H */