*.lzo
*.mod
*.mod.c
+*.ns_deps
*.o
*.o.*
*.patch
The syntax of the Module.symvers file is::
- <CRC> <Symbol> <module>
+ <CRC> <Symbol> <Namespace> <Module> <Export Type>
- 0x2d036834 scsi_remove_host drivers/scsi/scsi_mod
+ 0xe1cc2a05 usb_stor_suspend USB_STORAGE drivers/usb/storage/usb-storage EXPORT_SYMBOL_GPL
+
+ The fields are separated by tabs and values may be empty (e.g.
+ if no namespace is defined for an exported symbol).
For a kernel build without CONFIG_MODVERSIONS enabled, the CRC
would read 0x00000000.
--- /dev/null
+=================
+Symbol Namespaces
+=================
+
+The following document describes how to use Symbol Namespaces to structure the
+export surface of in-kernel symbols exported through the family of
+EXPORT_SYMBOL() macros.
+
+.. Table of Contents
+
+ === 1 Introduction
+ === 2 How to define Symbol Namespaces
+ --- 2.1 Using the EXPORT_SYMBOL macros
+ --- 2.2 Using the DEFAULT_SYMBOL_NAMESPACE define
+ === 3 How to use Symbols exported in Namespaces
+ === 4 Loading Modules that use namespaced Symbols
+ === 5 Automatically creating MODULE_IMPORT_NS statements
+
+1. Introduction
+===============
+
+Symbol Namespaces have been introduced as a means to structure the export
+surface of the in-kernel API. It allows subsystem maintainers to partition
+their exported symbols into separate namespaces. That is useful for
+documentation purposes (think of the SUBSYSTEM_DEBUG namespace) as well as for
+limiting the availability of a set of symbols for use in other parts of the
+kernel. As of today, modules that make use of symbols exported into namespaces,
+are required to import the namespace. Otherwise the kernel will, depending on
+its configuration, reject loading the module or warn about a missing import.
+
+2. How to define Symbol Namespaces
+==================================
+
+Symbols can be exported into namespace using different methods. All of them are
+changing the way EXPORT_SYMBOL and friends are instrumented to create ksymtab
+entries.
+
+2.1 Using the EXPORT_SYMBOL macros
+==================================
+
+In addition to the macros EXPORT_SYMBOL() and EXPORT_SYMBOL_GPL(), that allow
+exporting of kernel symbols to the kernel symbol table, variants of these are
+available to export symbols into a certain namespace: EXPORT_SYMBOL_NS() and
+EXPORT_SYMBOL_NS_GPL(). They take one additional argument: the namespace.
+Please note that due to macro expansion that argument needs to be a
+preprocessor symbol. E.g. to export the symbol `usb_stor_suspend` into the
+namespace `USB_STORAGE`, use::
+
+ EXPORT_SYMBOL_NS(usb_stor_suspend, USB_STORAGE);
+
+The corresponding ksymtab entry struct `kernel_symbol` will have the member
+`namespace` set accordingly. A symbol that is exported without a namespace will
+refer to `NULL`. There is no default namespace if none is defined. `modpost`
+and kernel/module.c make use the namespace at build time or module load time,
+respectively.
+
+2.2 Using the DEFAULT_SYMBOL_NAMESPACE define
+=============================================
+
+Defining namespaces for all symbols of a subsystem can be very verbose and may
+become hard to maintain. Therefore a default define (DEFAULT_SYMBOL_NAMESPACE)
+is been provided, that, if set, will become the default for all EXPORT_SYMBOL()
+and EXPORT_SYMBOL_GPL() macro expansions that do not specify a namespace.
+
+There are multiple ways of specifying this define and it depends on the
+subsystem and the maintainer's preference, which one to use. The first option
+is to define the default namespace in the `Makefile` of the subsystem. E.g. to
+export all symbols defined in usb-common into the namespace USB_COMMON, add a
+line like this to drivers/usb/common/Makefile::
+
+ ccflags-y += -DDEFAULT_SYMBOL_NAMESPACE=USB_COMMON
+
+That will affect all EXPORT_SYMBOL() and EXPORT_SYMBOL_GPL() statements. A
+symbol exported with EXPORT_SYMBOL_NS() while this definition is present, will
+still be exported into the namespace that is passed as the namespace argument
+as this argument has preference over a default symbol namespace.
+
+A second option to define the default namespace is directly in the compilation
+unit as preprocessor statement. The above example would then read::
+
+ #undef DEFAULT_SYMBOL_NAMESPACE
+ #define DEFAULT_SYMBOL_NAMESPACE USB_COMMON
+
+within the corresponding compilation unit before any EXPORT_SYMBOL macro is
+used.
+
+3. How to use Symbols exported in Namespaces
+============================================
+
+In order to use symbols that are exported into namespaces, kernel modules need
+to explicitly import these namespaces. Otherwise the kernel might reject to
+load the module. The module code is required to use the macro MODULE_IMPORT_NS
+for the namespaces it uses symbols from. E.g. a module using the
+usb_stor_suspend symbol from above, needs to import the namespace USB_STORAGE
+using a statement like::
+
+ MODULE_IMPORT_NS(USB_STORAGE);
+
+This will create a `modinfo` tag in the module for each imported namespace.
+This has the side effect, that the imported namespaces of a module can be
+inspected with modinfo::
+
+ $ modinfo drivers/usb/storage/ums-karma.ko
+ [...]
+ import_ns: USB_STORAGE
+ [...]
+
+
+It is advisable to add the MODULE_IMPORT_NS() statement close to other module
+metadata definitions like MODULE_AUTHOR() or MODULE_LICENSE(). Refer to section
+5. for a way to create missing import statements automatically.
+
+4. Loading Modules that use namespaced Symbols
+==============================================
+
+At module loading time (e.g. `insmod`), the kernel will check each symbol
+referenced from the module for its availability and whether the namespace it
+might be exported to has been imported by the module. The default behaviour of
+the kernel is to reject loading modules that don't specify sufficient imports.
+An error will be logged and loading will be failed with EINVAL. In order to
+allow loading of modules that don't satisfy this precondition, a configuration
+option is available: Setting MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=y will
+enable loading regardless, but will emit a warning.
+
+5. Automatically creating MODULE_IMPORT_NS statements
+=====================================================
+
+Missing namespaces imports can easily be detected at build time. In fact,
+modpost will emit a warning if a module uses a symbol from a namespace
+without importing it.
+MODULE_IMPORT_NS() statements will usually be added at a definite location
+(along with other module meta data). To make the life of module authors (and
+subsystem maintainers) easier, a script and make target is available to fixup
+missing imports. Fixing missing imports can be done with::
+
+ $ make nsdeps
+
+A typical scenario for module authors would be::
+
+ - write code that depends on a symbol from a not imported namespace
+ - `make`
+ - notice the warning of modpost telling about a missing import
+ - run `make nsdeps` to add the import to the correct code location
+
+For subsystem maintainers introducing a namespace, the steps are very similar.
+Again, `make nsdeps` will eventually add the missing namespace imports for
+in-tree modules::
+
+ - move or add symbols to a namespace (e.g. with EXPORT_SYMBOL_NS())
+ - `make` (preferably with an allmodconfig to cover all in-kernel
+ modules)
+ - notice the warning of modpost telling about a missing import
+ - run `make nsdeps` to add the import to the correct code location
+
maintainers and developers may however require EXPORT_SYMBOL_GPL()
when adding any new APIs or functionality.
+:c:func:`EXPORT_SYMBOL_NS()`
+----------------------------
+
+Defined in ``include/linux/export.h``
+
+This is the variant of `EXPORT_SYMBOL()` that allows specifying a symbol
+namespace. Symbol Namespaces are documented in
+``Documentation/kbuild/namespaces.rst``.
+
+:c:func:`EXPORT_SYMBOL_NS_GPL()`
+--------------------------------
+
+Defined in ``include/linux/export.h``
+
+This is the variant of `EXPORT_SYMBOL_GPL()` that allows specifying a symbol
+namespace. Symbol Namespaces are documented in
+``Documentation/kbuild/namespaces.rst``.
+
Routines and Conventions
========================
T: git git://git.kernel.org/pub/scm/linux/kernel/git/wtarreau/nolibc.git
F: tools/include/nolibc/
+NSDEPS
+M: Matthias Maennich <maennich@google.com>
+S: Maintained
+F: scripts/nsdeps
+
NTB AMD DRIVER
M: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
L: linux-ntb@googlegroups.com
@echo ' headerdep - Detect inclusion cycles in headers'
@echo ' coccicheck - Check with Coccinelle'
@echo ''
+ @echo 'Tools:'
+ @echo ' nsdeps - Generate missing symbol namespace dependencies'
+ @echo ''
@echo 'Kernel selftest:'
@echo ' kselftest - Build and run kernel selftest (run as root)'
@echo ' Build, install, and boot kernel before'
-o -name '*.ko.*' \
-o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
-o -name '*.dwo' -o -name '*.lst' \
- -o -name '*.su' -o -name '*.mod' \
+ -o -name '*.su' -o -name '*.mod' -o -name '*.ns_deps' \
-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
-o -name '*.lex.c' -o -name '*.tab.[ch]' \
-o -name '*.asn1.[ch]' \
tags TAGS cscope gtags: FORCE
$(call cmd,tags)
+# Script to generate missing namespace dependencies
+# ---------------------------------------------------------------------------
+
+PHONY += nsdeps
+
+nsdeps: modules
+ $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost nsdeps
+ $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
+
# Scripts to check various things for consistency
# ---------------------------------------------------------------------------
-#define KSYM_ALIGN 2
#define KCRC_ALIGN 2
#include <asm-generic/export.h>
ccflags-y := -I $(srctree)/drivers/scsi
+ccflags-y += -DDEFAULT_SYMBOL_NAMESPACE=USB_STORAGE
+
obj-$(CONFIG_USB_UAS) += uas.o
obj-$(CONFIG_USB_STORAGE) += usb-storage.o
MODULE_DESCRIPTION("Driver for Alauda-based card readers");
MODULE_AUTHOR("Daniel Drake <dsd@gentoo.org>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
/*
* Status bytes
MODULE_DESCRIPTION("SAT support for Cypress USB/ATA bridges with ATACB");
MODULE_AUTHOR("Matthieu Castet <castet.matthieu@free.fr>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
/*
* The table of devices
MODULE_DESCRIPTION("Driver for Datafab USB Compact Flash reader");
MODULE_AUTHOR("Jimmie Mayfield <mayfield+datafab@sackheads.org>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
struct datafab_info {
unsigned long sectors; /* total sector count */
MODULE_DESCRIPTION("Driver for ENE UB6250 reader");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
MODULE_FIRMWARE(SD_INIT1_FIRMWARE);
MODULE_FIRMWARE(SD_INIT2_FIRMWARE);
MODULE_FIRMWARE(SD_RW_FIRMWARE);
MODULE_DESCRIPTION("Driver for Freecom USB/IDE adaptor");
MODULE_AUTHOR("David Brown <usb-storage@davidb.org>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
#ifdef CONFIG_USB_STORAGE_DEBUG
static void pdump(struct us_data *us, void *ibuffer, int length);
MODULE_DESCRIPTION("Driver for In-System Design, Inc. ISD200 ASIC");
MODULE_AUTHOR("Björn Stenberg <bjorn@haxx.se>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
static int isd200_Initialization(struct us_data *us);
MODULE_DESCRIPTION("Driver for Lexar \"Jumpshot\" Compact Flash reader");
MODULE_AUTHOR("Jimmie Mayfield <mayfield+usb@sackheads.org>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
/*
* The table of devices
MODULE_DESCRIPTION("Driver for Rio Karma");
MODULE_AUTHOR("Bob Copeland <me@bobcopeland.com>, Keith Bennett <keith@mcs.st-and.ac.uk>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
#define RIO_PREFIX "RIOP\x00"
#define RIO_PREFIX_LEN 5
MODULE_DESCRIPTION("Maxtor USB OneTouch hard drive button driver");
MODULE_AUTHOR("Nick Sillik <n.sillik@temple.edu>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
#define ONETOUCH_PKT_LEN 0x02
#define ONETOUCH_BUTTON KEY_PROG1
MODULE_DESCRIPTION("Driver for Realtek USB Card Reader");
MODULE_AUTHOR("wwang <wei_wang@realsil.com.cn>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
static int auto_delink_en = 1;
module_param(auto_delink_en, int, S_IRUGO | S_IWUSR);
MODULE_DESCRIPTION("Driver for SanDisk SDDR-09 SmartMedia reader");
MODULE_AUTHOR("Andries Brouwer <aeb@cwi.nl>, Robert Baruch <autophile@starband.net>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
static int usb_stor_sddr09_dpcm_init(struct us_data *us);
static int sddr09_transport(struct scsi_cmnd *srb, struct us_data *us);
MODULE_DESCRIPTION("Driver for SanDisk SDDR-55 SmartMedia reader");
MODULE_AUTHOR("Simon Munton");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
/*
* The table of devices
MODULE_DESCRIPTION("Driver for SCM Microsystems (a.k.a. Shuttle) USB-ATAPI cable");
MODULE_AUTHOR("Daniel Drake <dsd@gentoo.org>, Robert Baruch <autophile@starband.net>");
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
/* Supported device types */
#define USBAT_DEV_HP8200 0x01
module_usb_driver(uas_driver);
MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(USB_STORAGE);
MODULE_AUTHOR(
"Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");
#ifndef KSYM_FUNC
#define KSYM_FUNC(x) x
#endif
-#ifdef CONFIG_64BIT
-#ifndef KSYM_ALIGN
+#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
+#define KSYM_ALIGN 4
+#elif defined(CONFIG_64BIT)
#define KSYM_ALIGN 8
-#endif
#else
-#ifndef KSYM_ALIGN
#define KSYM_ALIGN 4
#endif
-#endif
#ifndef KCRC_ALIGN
#define KCRC_ALIGN 4
#endif
.macro __put, val, name
#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
- .long \val - ., \name - .
+ .long \val - ., \name - ., 0
#elif defined(CONFIG_64BIT)
- .quad \val, \name
+ .quad \val, \name, 0
#else
- .long \val, \name
+ .long \val, \name, 0
#endif
.endm
#endif
#endif
.endm
-#undef __put
#if defined(CONFIG_TRIM_UNUSED_KSYMS)
#define THIS_MODULE ((struct module *)0)
#endif
+#define NS_SEPARATOR "."
+
#ifdef CONFIG_MODVERSIONS
/* Mark the CRC weak since genksyms apparently decides not to
* generate a checksums for some symbols */
asm(" .section \"___kcrctab" sec "+" #sym "\", \"a\" \n" \
" .weak __crc_" #sym " \n" \
" .long __crc_" #sym " - . \n" \
- " .previous \n");
+ " .previous \n")
#else
#define __CRC_SYMBOL(sym, sec) \
asm(" .section \"___kcrctab" sec "+" #sym "\", \"a\" \n" \
" .weak __crc_" #sym " \n" \
" .long __crc_" #sym " \n" \
- " .previous \n");
+ " .previous \n")
#endif
#else
#define __CRC_SYMBOL(sym, sec)
* absolute relocations that require runtime processing on relocatable
* kernels.
*/
+#define __KSYMTAB_ENTRY_NS(sym, sec, ns) \
+ __ADDRESSABLE(sym) \
+ asm(" .section \"___ksymtab" sec "+" #sym "\", \"a\" \n" \
+ " .balign 4 \n" \
+ "__ksymtab_" #sym NS_SEPARATOR #ns ": \n" \
+ " .long " #sym "- . \n" \
+ " .long __kstrtab_" #sym "- . \n" \
+ " .long __kstrtab_ns_" #sym "- . \n" \
+ " .previous \n")
+
#define __KSYMTAB_ENTRY(sym, sec) \
__ADDRESSABLE(sym) \
asm(" .section \"___ksymtab" sec "+" #sym "\", \"a\" \n" \
- " .balign 8 \n" \
+ " .balign 4 \n" \
"__ksymtab_" #sym ": \n" \
" .long " #sym "- . \n" \
" .long __kstrtab_" #sym "- . \n" \
+ " .long 0 \n" \
" .previous \n")
struct kernel_symbol {
int value_offset;
int name_offset;
+ int namespace_offset;
};
#else
+#define __KSYMTAB_ENTRY_NS(sym, sec, ns) \
+ static const struct kernel_symbol __ksymtab_##sym##__##ns \
+ asm("__ksymtab_" #sym NS_SEPARATOR #ns) \
+ __attribute__((section("___ksymtab" sec "+" #sym), used)) \
+ __aligned(sizeof(void *)) \
+ = { (unsigned long)&sym, __kstrtab_##sym, __kstrtab_ns_##sym }
+
#define __KSYMTAB_ENTRY(sym, sec) \
static const struct kernel_symbol __ksymtab_##sym \
+ asm("__ksymtab_" #sym) \
__attribute__((section("___ksymtab" sec "+" #sym), used)) \
- = { (unsigned long)&sym, __kstrtab_##sym }
+ __aligned(sizeof(void *)) \
+ = { (unsigned long)&sym, __kstrtab_##sym, NULL }
struct kernel_symbol {
unsigned long value;
const char *name;
+ const char *namespace;
};
#endif
#ifdef __GENKSYMS__
-#define ___EXPORT_SYMBOL(sym, sec) __GENKSYMS_EXPORT_SYMBOL(sym)
+#define ___EXPORT_SYMBOL(sym,sec) __GENKSYMS_EXPORT_SYMBOL(sym)
+#define ___EXPORT_SYMBOL_NS(sym,sec,ns) __GENKSYMS_EXPORT_SYMBOL(sym)
#else
-/* For every exported symbol, place a struct in the __ksymtab section */
-#define ___EXPORT_SYMBOL(sym, sec) \
+#define ___export_symbol_common(sym, sec) \
extern typeof(sym) sym; \
- __CRC_SYMBOL(sym, sec) \
+ __CRC_SYMBOL(sym, sec); \
static const char __kstrtab_##sym[] \
__attribute__((section("__ksymtab_strings"), used, aligned(1))) \
- = #sym; \
+ = #sym \
+
+/* For every exported symbol, place a struct in the __ksymtab section */
+#define ___EXPORT_SYMBOL_NS(sym, sec, ns) \
+ ___export_symbol_common(sym, sec); \
+ static const char __kstrtab_ns_##sym[] \
+ __attribute__((section("__ksymtab_strings"), used, aligned(1))) \
+ = #ns; \
+ __KSYMTAB_ENTRY_NS(sym, sec, ns)
+
+#define ___EXPORT_SYMBOL(sym, sec) \
+ ___export_symbol_common(sym, sec); \
__KSYMTAB_ENTRY(sym, sec)
#endif
* be reused in other execution contexts such as the UEFI stub or the
* decompressor.
*/
+#define __EXPORT_SYMBOL_NS(sym, sec, ns)
#define __EXPORT_SYMBOL(sym, sec)
#elif defined(CONFIG_TRIM_UNUSED_KSYMS)
#define __cond_export_sym_1(sym, sec) ___EXPORT_SYMBOL(sym, sec)
#define __cond_export_sym_0(sym, sec) /* nothing */
+#define __EXPORT_SYMBOL_NS(sym, sec, ns) \
+ __ksym_marker(sym); \
+ __cond_export_ns_sym(sym, sec, ns, __is_defined(__KSYM_##sym))
+#define __cond_export_ns_sym(sym, sec, ns, conf) \
+ ___cond_export_ns_sym(sym, sec, ns, conf)
+#define ___cond_export_ns_sym(sym, sec, ns, enabled) \
+ __cond_export_ns_sym_##enabled(sym, sec, ns)
+#define __cond_export_ns_sym_1(sym, sec, ns) ___EXPORT_SYMBOL_NS(sym, sec, ns)
+#define __cond_export_ns_sym_0(sym, sec, ns) /* nothing */
+
#else
-#define __EXPORT_SYMBOL(sym, sec) ___EXPORT_SYMBOL(sym, sec)
+#define __EXPORT_SYMBOL_NS(sym,sec,ns) ___EXPORT_SYMBOL_NS(sym,sec,ns)
+#define __EXPORT_SYMBOL(sym,sec) ___EXPORT_SYMBOL(sym,sec)
#endif /* CONFIG_MODULES */
+#ifdef DEFAULT_SYMBOL_NAMESPACE
+#undef __EXPORT_SYMBOL
+#define __EXPORT_SYMBOL(sym, sec) \
+ __EXPORT_SYMBOL_NS(sym, sec, DEFAULT_SYMBOL_NAMESPACE)
+#endif
+
#define EXPORT_SYMBOL(sym) __EXPORT_SYMBOL(sym, "")
#define EXPORT_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_gpl")
#define EXPORT_SYMBOL_GPL_FUTURE(sym) __EXPORT_SYMBOL(sym, "_gpl_future")
+#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL_NS(sym, "", ns)
+#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL_NS(sym, "_gpl", ns)
+
#ifdef CONFIG_UNUSED_SYMBOLS
#define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
#define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
#ifdef CONFIG_MODULES
+#define MODULE_IMPORT_NS(ns) MODULE_INFO(import_ns, #ns)
+
extern int modules_disabled; /* for sysctl */
/* Get/put a kernel symbol (calls must be symmetric) */
void *__symbol_get(const char *symbol);
config MODULE_SIG
bool "Module signature verification"
- depends on MODULES
select SYSTEM_DATA_VERIFICATION
help
Check modules for valid signatures upon load: the signature
config MODULE_COMPRESS
bool "Compress modules on installation"
- depends on MODULES
help
Compresses kernel modules when 'make modules_install' is run; gzip or
endchoice
+config MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
+ bool "Allow loading of modules with missing namespace imports"
+ help
+ Symbols exported with EXPORT_SYMBOL_NS*() are considered exported in
+ a namespace. A module that makes use of a symbol exported with such a
+ namespace is required to import the namespace via MODULE_IMPORT_NS().
+ There is no technical reason to enforce correct namespace imports,
+ but it creates consistency between symbols defining namespaces and
+ users importing namespaces they make use of. This option relaxes this
+ requirement and lifts the enforcement when loading a module.
+
+ If unsure, say N.
+
+config UNUSED_SYMBOLS
+ bool "Enable unused/obsolete exported symbols"
+ default y if X86
+ help
+ Unused but exported symbols make the kernel needlessly bigger. For
+ that reason most of these unused exports will soon be removed. This
+ option is provided temporarily to provide a transition period in case
+ some external kernel module needs one of these symbols anyway. If you
+ encounter such a case in your module, consider if you are actually
+ using the right API. (rationale: since nobody in the kernel is using
+ this in a module, there is a pretty good chance it's actually the
+ wrong interface to use). If you really need the symbol, please send a
+ mail to the linux kernel mailing list mentioning the symbol and why
+ you really need it, and what the merge plan to the mainline kernel for
+ your module is.
+
config TRIM_UNUSED_KSYMS
bool "Trim unused exported kernel symbols"
- depends on MODULES && !UNUSED_SYMBOLS
+ depends on !UNUSED_SYMBOLS
help
The kernel and some modules make many symbols available for
other modules to use via EXPORT_SYMBOL() and variants. Depending
#endif
}
-static int cmp_name(const void *va, const void *vb)
+static const char *kernel_symbol_namespace(const struct kernel_symbol *sym)
{
- const char *a;
- const struct kernel_symbol *b;
- a = va; b = vb;
- return strcmp(a, kernel_symbol_name(b));
+#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
+ if (!sym->namespace_offset)
+ return NULL;
+ return offset_to_ptr(&sym->namespace_offset);
+#else
+ return sym->namespace;
+#endif
+}
+
+static int cmp_name(const void *name, const void *sym)
+{
+ return strcmp(name, kernel_symbol_name(sym));
}
static bool find_exported_symbol_in_section(const struct symsearch *syms,
}
#endif /* CONFIG_MODVERSIONS */
+static char *get_modinfo(const struct load_info *info, const char *tag);
+static char *get_next_modinfo(const struct load_info *info, const char *tag,
+ char *prev);
+
+static int verify_namespace_is_imported(const struct load_info *info,
+ const struct kernel_symbol *sym,
+ struct module *mod)
+{
+ const char *namespace;
+ char *imported_namespace;
+
+ namespace = kernel_symbol_namespace(sym);
+ if (namespace) {
+ imported_namespace = get_modinfo(info, "import_ns");
+ while (imported_namespace) {
+ if (strcmp(namespace, imported_namespace) == 0)
+ return 0;
+ imported_namespace = get_next_modinfo(
+ info, "import_ns", imported_namespace);
+ }
+#ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
+ pr_warn(
+#else
+ pr_err(
+#endif
+ "%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
+ mod->name, kernel_symbol_name(sym), namespace);
+#ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
+ return -EINVAL;
+#endif
+ }
+ return 0;
+}
+
+
/* Resolve a symbol for this module. I.e. if we find one, record usage. */
static const struct kernel_symbol *resolve_symbol(struct module *mod,
const struct load_info *info,
goto getname;
}
+ err = verify_namespace_is_imported(info, sym, mod);
+ if (err) {
+ sym = ERR_PTR(err);
+ goto getname;
+ }
+
err = ref_module(mod, owner);
if (err) {
sym = ERR_PTR(err);
return string;
}
-static char *get_modinfo(struct load_info *info, const char *tag)
+static char *get_next_modinfo(const struct load_info *info, const char *tag,
+ char *prev)
{
char *p;
unsigned int taglen = strlen(tag);
* get_modinfo() calls made before rewrite_section_headers()
* must use sh_offset, as sh_addr isn't set!
*/
- for (p = (char *)info->hdr + infosec->sh_offset; p; p = next_string(p, &size)) {
+ char *modinfo = (char *)info->hdr + infosec->sh_offset;
+
+ if (prev) {
+ size -= prev - modinfo;
+ modinfo = next_string(prev, &size);
+ }
+
+ for (p = modinfo; p; p = next_string(p, &size)) {
if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
return p + taglen + 1;
}
return NULL;
}
+static char *get_modinfo(const struct load_info *info, const char *tag)
+{
+ return get_next_modinfo(info, tag, NULL);
+}
+
static void setup_modinfo(struct module *mod, struct load_info *info)
{
struct module_attribute *attr;
to keep kernel developers who have to stare a lot at assembler listings
sane.
-config UNUSED_SYMBOLS
- bool "Enable unused/obsolete exported symbols"
- default y if X86
- help
- Unused but exported symbols make the kernel needlessly bigger. For
- that reason most of these unused exports will soon be removed. This
- option is provided temporarily to provide a transition period in case
- some external kernel module needs one of these symbols anyway. If you
- encounter such a case in your module, consider if you are actually
- using the right API. (rationale: since nobody in the kernel is using
- this in a module, there is a pretty good chance it's actually the
- wrong interface to use). If you really need the symbol, please send a
- mail to the linux kernel mailing list mentioning the symbol and why
- you really need it, and what the merge plan to the mainline kernel for
- your module is.
-
config DEBUG_FS
bool "Debug Filesystem"
help
$(if $(KBUILD_EXTMOD),$(addprefix -e ,$(KBUILD_EXTRA_SYMBOLS))) \
$(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \
$(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \
- $(if $(KBUILD_MODPOST_WARN),-w)
+ $(if $(KBUILD_MODPOST_WARN),-w) \
+ $(if $(filter nsdeps,$(MAKECMDGOALS)),-d)
ifdef MODPOST_VMLINUX
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
endif
+nsdeps: __modpost
+
endif
.PHONY: $(PHONY)
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+//
+/// Adds missing MODULE_IMPORT_NS statements to source files
+///
+/// This script is usually called from scripts/nsdeps with -D ns=<namespace> to
+/// add a missing namespace tag to a module source file.
+///
+
+@has_ns_import@
+declarer name MODULE_IMPORT_NS;
+identifier virtual.ns;
+@@
+MODULE_IMPORT_NS(ns);
+
+// Add missing imports, but only adjacent to a MODULE_LICENSE statement.
+// That ensures we are adding it only to the main module source file.
+@do_import depends on !has_ns_import@
+declarer name MODULE_LICENSE;
+expression license;
+identifier virtual.ns;
+@@
+MODULE_LICENSE(license);
++ MODULE_IMPORT_NS(ns);
#
while ( <$module_symvers> ) {
chomp;
- my (undef, $symbol, $module, $gpl) = split;
+ my (undef, $symbol, $namespace, $module, $gpl) = split('\t');
$SYMBOL { $symbol } = [ $module , "0" , $symbol, $gpl];
}
close($module_symvers);
static int sec_mismatch_fatal = 0;
/* ignore missing files */
static int ignore_missing_files;
+/* write namespace dependencies */
+static int write_namespace_deps;
enum export {
export_plain, export_unused, export_gpl,
struct module *module;
unsigned int crc;
int crc_valid;
+ const char *namespace;
unsigned int weak:1;
unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
unsigned int kernel:1; /* 1 if symbol is from kernel
return NULL;
}
+static bool contains_namespace(struct namespace_list *list,
+ const char *namespace)
+{
+ struct namespace_list *ns_entry;
+
+ for (ns_entry = list; ns_entry != NULL; ns_entry = ns_entry->next)
+ if (strcmp(ns_entry->namespace, namespace) == 0)
+ return true;
+
+ return false;
+}
+
+static void add_namespace(struct namespace_list **list, const char *namespace)
+{
+ struct namespace_list *ns_entry;
+
+ if (!contains_namespace(*list, namespace)) {
+ ns_entry = NOFAIL(malloc(sizeof(struct namespace_list) +
+ strlen(namespace) + 1));
+ strcpy(ns_entry->namespace, namespace);
+ ns_entry->next = *list;
+ *list = ns_entry;
+ }
+}
+
+static bool module_imports_namespace(struct module *module,
+ const char *namespace)
+{
+ return contains_namespace(module->imported_namespaces, namespace);
+}
+
static const struct {
const char *str;
enum export export;
return export_unknown;
}
+static const char *sym_extract_namespace(const char **symname)
+{
+ size_t n;
+ char *dupsymname;
+
+ n = strcspn(*symname, ".");
+ if (n < strlen(*symname) - 1) {
+ dupsymname = NOFAIL(strdup(*symname));
+ dupsymname[n] = '\0';
+ *symname = dupsymname;
+ return dupsymname + n + 1;
+ }
+
+ return NULL;
+}
+
/**
* Add an exported symbol - it may have already been added without a
* CRC, in this case just update the CRC
**/
-static struct symbol *sym_add_exported(const char *name, struct module *mod,
- enum export export)
+static struct symbol *sym_add_exported(const char *name, const char *namespace,
+ struct module *mod, enum export export)
{
struct symbol *s = find_symbol(name);
if (!s) {
s = new_symbol(name, mod, export);
+ s->namespace = namespace;
} else {
if (!s->preloaded) {
- warn("%s: '%s' exported twice. Previous export "
- "was in %s%s\n", mod->name, name,
- s->module->name,
- is_vmlinux(s->module->name) ?"":".ko");
+ warn("%s: '%s' exported twice. Previous export was in %s%s\n",
+ mod->name, name, s->module->name,
+ is_vmlinux(s->module->name) ? "" : ".ko");
} else {
/* In case Module.symvers was out of date */
s->module = mod;
unsigned int crc;
enum export export;
bool is_crc = false;
+ const char *name, *namespace;
if ((!is_vmlinux(mod->name) || mod->is_dot_o) &&
strstarts(symname, "__ksymtab"))
default:
/* All exported symbols */
if (strstarts(symname, "__ksymtab_")) {
- sym_add_exported(symname + strlen("__ksymtab_"), mod,
- export);
+ name = symname + strlen("__ksymtab_");
+ namespace = sym_extract_namespace(&name);
+ sym_add_exported(name, namespace, mod, export);
}
if (strcmp(symname, "init_module") == 0)
mod->has_init = 1;
const char *symname;
char *version;
char *license;
+ char *namespace;
struct module *mod;
struct elf_info info = { };
Elf_Sym *sym;
license = get_next_modinfo(&info, "license", license);
}
+ namespace = get_modinfo(&info, "import_ns");
+ while (namespace) {
+ add_namespace(&mod->imported_namespaces, namespace);
+ namespace = get_next_modinfo(&info, "import_ns", namespace);
+ }
+
for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
symname = remove_dot(info.strtab + sym->st_name);
basename++;
else
basename = mod->name;
+
+ if (exp->namespace) {
+ add_namespace(&mod->required_namespaces,
+ exp->namespace);
+
+ if (!write_namespace_deps &&
+ !module_imports_namespace(mod, exp->namespace)) {
+ warn("module %s uses symbol %s from namespace %s, but does not import it.\n",
+ basename, exp->name, exp->namespace);
+ }
+ }
+
if (!mod->gpl_compatible)
check_for_gpl_usage(exp->export, basename, exp->name);
check_for_unused(exp->export, basename, exp->name);
return;
while ((line = get_next_line(&pos, file, size))) {
- char *symname, *modname, *d, *export, *end;
+ char *symname, *namespace, *modname, *d, *export, *end;
unsigned int crc;
struct module *mod;
struct symbol *s;
if (!(symname = strchr(line, '\t')))
goto fail;
*symname++ = '\0';
- if (!(modname = strchr(symname, '\t')))
+ if (!(namespace = strchr(symname, '\t')))
+ goto fail;
+ *namespace++ = '\0';
+ if (!(modname = strchr(namespace, '\t')))
goto fail;
*modname++ = '\0';
if ((export = strchr(modname, '\t')) != NULL)
mod = new_module(modname);
mod->skip = 1;
}
- s = sym_add_exported(symname, mod, export_no(export));
+ s = sym_add_exported(symname, namespace, mod,
+ export_no(export));
s->kernel = kernel;
s->preloaded = 1;
s->is_static = 0;
{
struct buffer buf = { };
struct symbol *symbol;
+ const char *namespace;
int n;
for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
symbol = symbolhash[n];
while (symbol) {
- if (dump_sym(symbol))
- buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
- symbol->crc, symbol->name,
- symbol->module->name,
- export_str(symbol->export));
+ if (dump_sym(symbol)) {
+ namespace = symbol->namespace;
+ buf_printf(&buf, "0x%08x\t%s\t%s\t%s\t%s\n",
+ symbol->crc, symbol->name,
+ namespace ? namespace : "",
+ symbol->module->name,
+ export_str(symbol->export));
+ }
symbol = symbol->next;
}
}
free(buf.p);
}
+static void write_namespace_deps_files(void)
+{
+ struct module *mod;
+ struct namespace_list *ns;
+ struct buffer ns_deps_buf = {};
+
+ for (mod = modules; mod; mod = mod->next) {
+ char fname[PATH_MAX];
+
+ if (mod->skip)
+ continue;
+
+ ns_deps_buf.pos = 0;
+
+ for (ns = mod->required_namespaces; ns; ns = ns->next)
+ buf_printf(&ns_deps_buf, "%s\n", ns->namespace);
+
+ if (ns_deps_buf.pos == 0)
+ continue;
+
+ sprintf(fname, "%s.ns_deps", mod->name);
+ write_if_changed(&ns_deps_buf, fname);
+ }
+}
+
struct ext_sym_list {
struct ext_sym_list *next;
const char *file;
struct ext_sym_list *extsym_iter;
struct ext_sym_list *extsym_start = NULL;
- while ((opt = getopt(argc, argv, "i:I:e:mnsT:o:awE")) != -1) {
+ while ((opt = getopt(argc, argv, "i:I:e:mnsT:o:awEd")) != -1) {
switch (opt) {
case 'i':
kernel_read = optarg;
case 'E':
sec_mismatch_fatal = 1;
break;
+ case 'd':
+ write_namespace_deps = 1;
+ break;
default:
exit(1);
}
err |= check_modname_len(mod);
err |= check_exports(mod);
+ if (write_namespace_deps)
+ continue;
+
add_header(&buf, mod);
add_intree_flag(&buf, !external_module);
add_retpoline(&buf);
sprintf(fname, "%s.mod.c", mod->name);
write_if_changed(&buf, fname);
}
+
+ if (write_namespace_deps) {
+ write_namespace_deps_files();
+ return 0;
+ }
+
if (dump_write)
write_dump(dump_write);
if (sec_mismatch_count && sec_mismatch_fatal)
void
buf_write(struct buffer *buf, const char *s, int len);
+struct namespace_list {
+ struct namespace_list *next;
+ char namespace[0];
+};
+
struct module {
struct module *next;
const char *name;
struct buffer dev_table_buf;
char srcversion[25];
int is_dot_o;
+ // Required namespace dependencies
+ struct namespace_list *required_namespaces;
+ // Actual imported namespaces
+ struct namespace_list *imported_namespaces;
};
struct elf_info {
--- /dev/null
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Linux kernel symbol namespace import generator
+#
+# This script requires a minimum spatch version.
+SPATCH_REQ_VERSION="1.0.4"
+
+DIR="$(dirname $(readlink -f $0))/.."
+SPATCH="`which ${SPATCH:=spatch}`"
+if [ ! -x "$SPATCH" ]; then
+ echo 'spatch is part of the Coccinelle project and is available at http://coccinelle.lip6.fr/'
+ exit 1
+fi
+
+SPATCH_REQ_VERSION_NUM=$(echo $SPATCH_REQ_VERSION | ${DIR}/scripts/ld-version.sh)
+SPATCH_VERSION=$($SPATCH --version | head -1 | awk '{print $3}')
+SPATCH_VERSION_NUM=$(echo $SPATCH_VERSION | ${DIR}/scripts/ld-version.sh)
+
+if [ "$SPATCH_VERSION_NUM" -lt "$SPATCH_REQ_VERSION_NUM" ] ; then
+ echo "spatch needs to be version $SPATCH_REQ_VERSION or higher"
+ exit 1
+fi
+
+generate_deps_for_ns() {
+ $SPATCH --very-quiet --in-place --sp-file \
+ $srctree/scripts/coccinelle/misc/add_namespace.cocci -D ns=$1 $2
+}
+
+generate_deps() {
+ local mod_name=`basename $@ .ko`
+ local mod_file=`echo $@ | sed -e 's/\.ko/\.mod/'`
+ local ns_deps_file=`echo $@ | sed -e 's/\.ko/\.ns_deps/'`
+ if [ ! -f "$ns_deps_file" ]; then return; fi
+ local mod_source_files=`cat $mod_file | sed -n 1p \
+ | sed -e 's/\.o/\.c/g' \
+ | sed "s/[^ ]* */${srctree}\/&/g"`
+ for ns in `cat $ns_deps_file`; do
+ echo "Adding namespace $ns to module $mod_name (if needed)."
+ generate_deps_for_ns $ns $mod_source_files
+ # sort the imports
+ for source_file in $mod_source_files; do
+ sed '/MODULE_IMPORT_NS/Q' $source_file > ${source_file}.tmp
+ offset=$(wc -l ${source_file}.tmp | awk '{print $1;}')
+ cat $source_file | grep MODULE_IMPORT_NS | sort -u >> ${source_file}.tmp
+ tail -n +$((offset +1)) ${source_file} | grep -v MODULE_IMPORT_NS >> ${source_file}.tmp
+ if ! diff -q ${source_file} ${source_file}.tmp; then
+ mv ${source_file}.tmp ${source_file}
+ else
+ rm ${source_file}.tmp
+ fi
+ done
+ done
+}
+
+for f in `cat $objtree/modules.order`; do
+ generate_deps $f
+done
+
projects / linux-2.6-block.git / commitdiff