Unverified Commit 6d3c3ca4 authored by Vlastimil Babka's avatar Vlastimil Babka Committed by Christian Brauner
Browse files

module: Rename EXPORT_SYMBOL_GPL_FOR_MODULES to EXPORT_SYMBOL_FOR_MODULES 

Christoph suggested that the explicit _GPL_ can be dropped from the
module namespace export macro, as it's intended for in-tree modules
only. It would be possible to restrict it technically, but it was
pointed out [2] that some cases of using an out-of-tree build of an
in-tree module with the same name are legitimate. But in that case those
also have to be GPL anyway so it's unnecessary to spell it out in the
macro name.

Link: https://lore.kernel.org/all/aFleJN_fE-RbSoFD@infradead.org/ [1]
Link: https://lore.kernel.org/all/CAK7LNATRkZHwJGpojCnvdiaoDnP%2BaeUXgdey5sb_8muzdWTMkA@mail.gmail.com/

 [2]
Suggested-by: default avatarChristoph Hellwig <hch@infradead.org>
Reviewed-by: default avatarShivank Garg <shivankg@amd.com>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Acked-by: default avatarNicolas Schier <n.schier@avm.de>
Reviewed-by: default avatarDaniel Gomez <da.gomez@samsung.com>
Reviewed-by: default avatarChristian Brauner <brauner@kernel.org>
Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/20250808-export_modules-v4-1-426945bcc5e1@suse.cz


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 593d9e4c

Documentation/core-api/symbol-namespaces.rst

+6 −5
Original line number Diff line number Diff line
@@ -76,20 +76,21 @@ unit as preprocessor statement. The above example would then read:: 
within the corresponding compilation unit before the #include for

<linux/export.h>. Typically it's placed before the first #include statement.



Using the EXPORT_SYMBOL_GPL_FOR_MODULES() macro

-----------------------------------------------

Using the EXPORT_SYMBOL_FOR_MODULES() macro

-------------------------------------------



Symbols exported using this macro are put into a module namespace. This

namespace cannot be imported.

namespace cannot be imported. These exports are GPL-only as they are only

intended for in-tree modules.



The macro takes a comma separated list of module names, allowing only those

modules to access this symbol. Simple tail-globs are supported.



For example::



  EXPORT_SYMBOL_GPL_FOR_MODULES(preempt_notifier_inc, "kvm,kvm-*")

  EXPORT_SYMBOL_FOR_MODULES(preempt_notifier_inc, "kvm,kvm-*")



will limit usage of this symbol to modules whoes name matches the given

will limit usage of this symbol to modules whose name matches the given

patterns.



How to use Symbols exported in Namespaces

drivers/tty/serial/8250/8250_rsa.c

+4 −4
Original line number Diff line number Diff line
@@ -147,7 +147,7 @@ void rsa_enable(struct uart_8250_port *up) 
	if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)

		serial_out(up, UART_RSA_FRR, 0);

}

EXPORT_SYMBOL_GPL_FOR_MODULES(rsa_enable, "8250_base");

EXPORT_SYMBOL_FOR_MODULES(rsa_enable, "8250_base");



/*

 * Attempts to turn off the RSA FIFO and resets the RSA board back to 115kbps compat mode. It is
@@ -179,7 +179,7 @@ void rsa_disable(struct uart_8250_port *up) 
		up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;

	uart_port_unlock_irq(&up->port);

}

EXPORT_SYMBOL_GPL_FOR_MODULES(rsa_disable, "8250_base");

EXPORT_SYMBOL_FOR_MODULES(rsa_disable, "8250_base");



void rsa_autoconfig(struct uart_8250_port *up)

{
@@ -192,7 +192,7 @@ void rsa_autoconfig(struct uart_8250_port *up) 
	if (__rsa_enable(up))

		up->port.type = PORT_RSA;

}

EXPORT_SYMBOL_GPL_FOR_MODULES(rsa_autoconfig, "8250_base");

EXPORT_SYMBOL_FOR_MODULES(rsa_autoconfig, "8250_base");



void rsa_reset(struct uart_8250_port *up)

{
@@ -201,7 +201,7 @@ void rsa_reset(struct uart_8250_port *up) 


	serial_out(up, UART_RSA_FRR, 0);

}

EXPORT_SYMBOL_GPL_FOR_MODULES(rsa_reset, "8250_base");

EXPORT_SYMBOL_FOR_MODULES(rsa_reset, "8250_base");



#ifdef CONFIG_SERIAL_8250_DEPRECATED_OPTIONS

#ifndef MODULE

fs/anon_inodes.c

+1 −1
Original line number Diff line number Diff line
@@ -129,7 +129,7 @@ struct inode *anon_inode_make_secure_inode(struct super_block *sb, const char *n 
	}

	return inode;

}

EXPORT_SYMBOL_GPL_FOR_MODULES(anon_inode_make_secure_inode, "kvm");

EXPORT_SYMBOL_FOR_MODULES(anon_inode_make_secure_inode, "kvm");



static struct file *__anon_inode_getfile(const char *name,

					 const struct file_operations *fops,

include/linux/export.h

+1 −1
Original line number Diff line number Diff line
@@ -91,6 +91,6 @@ 
#define EXPORT_SYMBOL_NS(sym, ns)	__EXPORT_SYMBOL(sym, "", ns)

#define EXPORT_SYMBOL_NS_GPL(sym, ns)	__EXPORT_SYMBOL(sym, "GPL", ns)



#define EXPORT_SYMBOL_GPL_FOR_MODULES(sym, mods) __EXPORT_SYMBOL(sym, "GPL", "module:" mods)

#define EXPORT_SYMBOL_FOR_MODULES(sym, mods) __EXPORT_SYMBOL(sym, "GPL", "module:" mods)



#endif /* _LINUX_EXPORT_H */