Commit f4fdb17c authored by Masahiro Yamada's avatar Masahiro Yamada
Browse files

modpost: introduce module_alias_printf() helper 



The generic ->do_entry() handler is currently limited to returning
a single alias string.

However, this is not flexible enough for several subsystems, which
currently require their own implementations:

 - do_usb_table()
 - do_of_table()
 - do_pnp_device_entry()
 - do_pnp_card_entries()

This commit introduces a helper function so that these special cases can
add multiple MODULE_ALIAS() and then migrate to the generic framework.

Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
parent b7bca42d

scripts/mod/file2alias.c

+66 −25
Original line number Diff line number Diff line
@@ -10,6 +10,12 @@ 
 * of the GNU General Public License, incorporated herein by reference.

 */



#include <stdarg.h>

#include <stdio.h>



#include "list.h"

#include "xalloc.h"



#include "modpost.h"

#include "devicetable-offsets.h"
@@ -31,6 +37,58 @@ typedef Elf64_Addr kernel_ulong_t; 
#include <ctype.h>

#include <stdbool.h>



/**

 * module_alias_printf - add auto-generated MODULE_ALIAS()

 *

 * @mod: module

 * @append_wildcard: append '*' for future extension if not exist yet

 * @fmt: printf(3)-like format

 */

static void __attribute__((format (printf, 3, 4)))

module_alias_printf(struct module *mod, bool append_wildcard,

		    const char *fmt, ...)

{

	struct module_alias *new;

	size_t len;

	int n;

	va_list ap;



	/* Determine required size. */

	va_start(ap, fmt);

	n = vsnprintf(NULL, 0, fmt, ap);

	va_end(ap);



	if (n < 0) {

		error("vsnprintf failed\n");

		return;

	}



	len = n + 1;	/* extra byte for '\0' */



	if (append_wildcard)

		len++;	/* extra byte for '*' */



	new = xmalloc(sizeof(*new) + len);



	/* Now, really print it to the allocated buffer */

	va_start(ap, fmt);

	n = vsnprintf(new->str, len, fmt, ap);

	va_end(ap);



	if (n < 0) {

		error("vsnprintf failed\n");

		free(new);

		return;

	}



	if (append_wildcard && (n == 0 || new->str[n - 1] != '*')) {

		new->str[n] = '*';

		new->str[n + 1] = '\0';

	}



	list_add_tail(&new->node, &mod->aliases);

}



typedef uint32_t	__u32;

typedef uint16_t	__u16;

typedef unsigned char	__u8;
@@ -229,9 +287,7 @@ static void do_usb_entry(void *symval, 
	ADD(alias, "in", match_flags&USB_DEVICE_ID_MATCH_INT_NUMBER,

	    bInterfaceNumber);



	add_wildcard(alias);

	buf_printf(&mod->dev_table_buf,

		   "MODULE_ALIAS(\"%s\");\n", alias);

	module_alias_printf(mod, true, "%s", alias);

}



/* Handles increment/decrement of BCD formatted integers */
@@ -375,10 +431,8 @@ static void do_of_entry_multi(void *symval, struct module *mod) 
		if (isspace(*tmp))

			*tmp = '_';



	buf_printf(&mod->dev_table_buf, "MODULE_ALIAS(\"%s\");\n", alias);

	strcat(alias, "C");

	add_wildcard(alias);

	buf_printf(&mod->dev_table_buf, "MODULE_ALIAS(\"%s\");\n", alias);

	module_alias_printf(mod, false, "%s", alias);

	module_alias_printf(mod, false, "%sC*", alias);

}



static void do_of_table(void *symval, unsigned long size,
@@ -608,14 +662,12 @@ static void do_pnp_device_entry(void *symval, unsigned long size, 
		char acpi_id[sizeof(*id)];

		int j;



		buf_printf(&mod->dev_table_buf,

			   "MODULE_ALIAS(\"pnp:d%s*\");\n", *id);

		module_alias_printf(mod, false, "pnp:d%s*", *id);



		/* fix broken pnp bus lowercasing */

		for (j = 0; j < sizeof(acpi_id); j++)

			acpi_id[j] = toupper((*id)[j]);

		buf_printf(&mod->dev_table_buf,

			   "MODULE_ALIAS(\"acpi*:%s:*\");\n", acpi_id);

		module_alias_printf(mod, false, "acpi*:%s:*", acpi_id);

	}

}
@@ -666,14 +718,12 @@ static void do_pnp_card_entries(void *symval, unsigned long size, 
				char acpi_id[PNP_ID_LEN];

				int k;



				buf_printf(&mod->dev_table_buf,

					   "MODULE_ALIAS(\"pnp:d%s*\");\n", id);

				module_alias_printf(mod, false, "pnp:d%s*", id);



				/* fix broken pnp bus lowercasing */

				for (k = 0; k < sizeof(acpi_id); k++)

					acpi_id[k] = toupper(id[k]);

				buf_printf(&mod->dev_table_buf,

					   "MODULE_ALIAS(\"acpi*:%s:*\");\n", acpi_id);

				module_alias_printf(mod, false, "acpi*:%s:*", acpi_id);

			}

		}

	}
@@ -1534,8 +1584,7 @@ static void do_table(void *symval, unsigned long size, 


	for (i = 0; i < size; i += id_size) {

		if (do_entry(mod->name, symval+i, alias)) {

			buf_printf(&mod->dev_table_buf,

				   "MODULE_ALIAS(\"%s\");\n", alias);

			module_alias_printf(mod, false, "%s", alias);

		}

	}

}
@@ -1660,11 +1709,3 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, 
	}

	free(zeros);

}
 


/* Now add out buffered information to the generated C source */

void add_moddevtable(struct buffer *buf, struct module *mod)

{

	buf_printf(buf, "\n");

	buf_write(buf, mod->dev_table_buf.p, mod->dev_table_buf.pos);

	free(mod->dev_table_buf.p);

}

scripts/mod/modpost.c

+10 −1
Original line number Diff line number Diff line
@@ -176,6 +176,7 @@ static struct module *new_module(const char *name, size_t namelen) 
	INIT_LIST_HEAD(&mod->unresolved_symbols);

	INIT_LIST_HEAD(&mod->missing_namespaces);

	INIT_LIST_HEAD(&mod->imported_namespaces);

	INIT_LIST_HEAD(&mod->aliases);



	memcpy(mod->name, name, namelen);

	mod->name[namelen] = '\0';
@@ -1966,6 +1967,7 @@ static void write_vmlinux_export_c_file(struct module *mod) 
static void write_mod_c_file(struct module *mod)

{

	struct buffer buf = { };

	struct module_alias *alias, *next;

	char fname[PATH_MAX];

	int ret;
@@ -1973,7 +1975,14 @@ static void write_mod_c_file(struct module *mod) 
	add_exported_symbols(&buf, mod);

	add_versions(&buf, mod);

	add_depends(&buf, mod);

	add_moddevtable(&buf, mod);



	buf_printf(&buf, "\n");

	list_for_each_entry_safe(alias, next, &mod->aliases, node) {

		buf_printf(&buf, "MODULE_ALIAS(\"%s\");\n", alias->str);

		list_del(&alias->node);

		free(alias);

	}



	add_srcversion(&buf, mod);



	ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name);

scripts/mod/modpost.h

+17 −2
Original line number Diff line number Diff line
@@ -79,6 +79,22 @@ buf_printf(struct buffer *buf, const char *fmt, ...); 
void

buf_write(struct buffer *buf, const char *s, int len);



/**

 * struct module_alias - auto-generated MODULE_ALIAS()

 *

 * @node: linked to module::aliases

 * @str: a string for MODULE_ALIAS()

 */

struct module_alias {

	struct list_head node;

	char str[];

};



/**

 * struct module - represent a module (vmlinux or *.ko)

 *

 * @aliases: list head for module_aliases

 */

struct module {

	struct list_head list;

	struct list_head exported_symbols;
@@ -89,12 +105,12 @@ struct module { 
	bool seen;

	bool has_init;

	bool has_cleanup;

	struct buffer dev_table_buf;

	char	     srcversion[25];

	// Missing namespace dependencies

	struct list_head missing_namespaces;

	// Actual imported namespaces

	struct list_head imported_namespaces;

	struct list_head aliases;

	char name[];

};
@@ -170,7 +186,6 @@ Elf_Sym *symsearch_find_nearest(struct elf_info *elf, Elf_Addr addr, 
/* file2alias.c */

void handle_moddevtable(struct module *mod, struct elf_info *info,

			Elf_Sym *sym, const char *symname);

void add_moddevtable(struct buffer *buf, struct module *mod);



/* sumversion.c */

void get_src_version(const char *modname, char sum[], unsigned sumlen);