All of lore.kernel.org
 help / color / mirror / Atom feed
From: Al Viro <viro@ZenIV.linux.org.uk>
To: linux-arch@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 02/12] EXPORT_SYMBOL() for asm
Date: Fri, 29 Jan 2016 19:18:24 +0000	[thread overview]
Message-ID: <1454095114-4128-2-git-send-email-viro@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20160129191744.GB17997@ZenIV.linux.org.uk>

From: Al Viro <viro@zeniv.linux.org.uk>

Add asm-usable variants of EXPORT_SYMBOL/EXPORT_SYMBOL_GPL.  This
commit just adds the default implementation; most of the architectures
can simply add export.h to asm/Kbuild and start using <asm/export.h>
from assembler.  The area where the things might diverge from default
is the alignment; normally it's 8 bytes on 64bit targets and 4 on
32bit ones, both for unsigned long and for struct kernel_symbol.

Unfortunately, amd64 and m68k are unusual - m68k aligns to 2 bytes
(for both) and amd64 aligns struct kernel_symbol to 16 bytes.  For
those we'll need to have asm/export.h overriding the constants used
by generic version (KSYM_ALIGN and KCRC_ALIGN for kernel_symbol and
unsigned long resp.) and including asm-generic/export.h.

And no, __alignof__ would not do the trick - on amd64 __alignof__
of struct kernel_symbol is 8, not 16.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/asm-generic/export.h | 61 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 include/asm-generic/export.h

diff --git a/include/asm-generic/export.h b/include/asm-generic/export.h
new file mode 100644
index 0000000..a1d44be
--- /dev/null
+++ b/include/asm-generic/export.h
@@ -0,0 +1,61 @@
+#ifndef __ASM_GENERIC_EXPORT_H
+#define __ASM_GENERIC_EXPORT_H
+
+#ifdef CONFIG_64BIT
+#define __put .quad
+#ifndef KSYM_ALIGN
+#define KSYM_ALIGN 8
+#endif
+#ifndef KCRC_ALIGN
+#define KCRC_ALIGN 8
+#endif
+#else
+#define __put .long
+#ifndef KSYM_ALIGN
+#define KSYM_ALIGN 4
+#endif
+#ifndef KCRC_ALIGN
+#define KCRC_ALIGN 4
+#endif
+#endif
+/*
+ * note on .section use: @progbits vs %progbits nastiness doesn't matter,
+ * since we immediately emit into those sections anyway.
+ */
+.macro __EXPORT_SYMBOL name,sec
+#ifdef CONFIG_MODULES
+	.globl __ksymtab_\name
+	.section ___ksymtab\sec+\name,"a"
+	.balign KSYM_ALIGN
+#ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
+	___ksymtab_\name: __put _\name, ___kstrtab_\name
+#else
+	__ksymtab_\name: __put \name, __kstrtab_\name
+#endif
+	.previous
+	.section __ksymtab_strings,"a"
+#ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
+	___kstrtab_\name: .asciz "_\name"
+#else
+	__kstrtab_\name: .asciz "\name"
+#endif
+	.previous
+#ifdef CONFIG_MODVERSIONS
+	.section ___kcrctab\sec+\name,"a"
+	.balign KCRC_ALIGN
+#ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
+	___kcrctab_\name: __put ___crc_\name
+	.weak	___crc_\name
+#else
+	__kcrctab_\name: __put __crc_\name
+	.weak	__crc_\name
+#endif
+	.previous
+#endif
+#endif
+.endm
+#undef __put
+#define EXPORT_SYMBOL(name) __EXPORT_SYMBOL name
+#define EXPORT_SYMBOL_GPL(name) __EXPORT_SYMBOL name, _gpl
+
+#endif
-- 
2.1.4

  parent reply	other threads:[~2016-01-29 19:18 UTC|newest]

Thread overview: 47+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-29 19:17 [RFC][PATCHSET] allowing exports in *.S Al Viro
2016-01-29 19:18 ` [PATCH 01/12] [kbuild] handle exports in lib-y objects reliably Al Viro
2016-01-29 19:18 ` Al Viro [this message]
2016-01-29 21:06   ` [PATCH 02/12] EXPORT_SYMBOL() for asm Arnd Bergmann
2016-01-29 19:18 ` [PATCH 03/12] x86: move exports to actual definitions Al Viro
2016-02-01  8:12   ` Thomas Gleixner
2016-01-29 19:18 ` [PATCH 04/12] alpha: " Al Viro
2016-01-29 19:18 ` [PATCH 05/12] m68k: move exports to definitions Al Viro
2016-02-01 10:52   ` Geert Uytterhoeven
2016-02-01 12:18     ` Al Viro
2016-02-01 13:30       ` Geert Uytterhoeven
2016-02-01 14:53         ` Al Viro
2016-02-01 15:32           ` Geert Uytterhoeven
2016-01-29 19:18 ` [PATCH 06/12] s390: " Al Viro
2016-02-02 11:29   ` Heiko Carstens
2016-01-29 19:18 ` [PATCH 07/12] arm: " Al Viro
2016-01-29 19:18 ` [PATCH 08/12] ppc: " Al Viro
2016-01-29 19:18 ` [PATCH 09/12] sparc: " Al Viro
2016-01-30  7:08   ` David Miller
2016-01-29 19:18 ` [PATCH 10/12] ia64: " Al Viro
2016-01-29 19:18 ` [PATCH 11/12] [sparc] unify 32bit and 64bit string.h Al Viro
2016-01-30  7:08   ` David Miller
2016-01-29 19:18 ` [PATCH 12/12] sparc32: debride memcpy.S a bit Al Viro
2016-01-30  7:07   ` David Miller
2016-02-01 15:12 ` [PATCH 02/12] EXPORT_SYMBOL() for asm David Howells
2016-02-03 21:19 ` [RFC][PATCHSET v2] allowing exports in *.S Al Viro
2016-02-03 21:20   ` [PATCH v2 01/13] [kbuild] handle exports in lib-y objects reliably Al Viro
2016-02-04 22:33     ` Michal Marek
2016-02-05  0:18       ` Al Viro
2016-02-03 21:20   ` [PATCH v2 02/13] EXPORT_SYMBOL() for asm Al Viro
2016-02-04 18:06     ` Al Viro
2016-02-10 22:15     ` Nicolas Pitre
2016-02-03 21:20   ` [PATCH v2 03/13] x86: move exports to actual definitions Al Viro
2016-02-03 21:20   ` [PATCH v2 04/13] alpha: " Al Viro
2016-02-03 21:20   ` [PATCH v2 05/13] m68k: move exports to definitions Al Viro
2016-02-03 21:20   ` [PATCH v2 06/13] s390: " Al Viro
2016-02-03 21:20   ` [PATCH v2 07/13] arm: " Al Viro
2016-02-10 21:56     ` Nicolas Pitre
2016-02-03 21:20   ` [PATCH v2 08/13] ppc: " Al Viro
2016-02-03 21:20   ` [PATCH v2 09/13] ppc: get rid of unreachable abs() implementation Al Viro
2016-02-03 21:20   ` [PATCH v2 10/13] sparc: move exports to definitions Al Viro
2016-02-03 21:20   ` [PATCH v2 11/13] [sparc] unify 32bit and 64bit string.h Al Viro
2016-02-03 21:20   ` [PATCH v2 12/13] sparc32: debride memcpy.S a bit Al Viro
2016-02-03 21:20   ` [PATCH v2 13/13] ia64: move exports to definitions Al Viro
2016-08-02 14:01   ` [RFC][PATCHSET v2] allowing exports in *.S Michal Marek
2016-08-16  5:48     ` Michal Marek
2016-08-16  5:57       ` Michal Marek

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1454095114-4128-2-git-send-email-viro@ZenIV.linux.org.uk \
    --to=viro@zeniv.linux.org.uk \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.