zfs/include/linux/kallsyms_compat.h

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/*****************************************************************************\
* Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
* Copyright (C) 2007 The Regents of the University of California.
* Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
* Written by Brian Behlendorf <behlendorf1@llnl.gov>.
* UCRL-CODE-235197
*
* This file is part of the SPL, Solaris Porting Layer.
* For details, see <http://zfsonlinux.org/>.
*
* The SPL is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* The SPL is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with the SPL. If not, see <http://www.gnu.org/licenses/>.
\*****************************************************************************/
Linux VM Integration Cleanup Remove all instances of functions being reimplemented in the SPL. When the prototypes are available in the linux headers but the function address itself is not exported use kallsyms_lookup_name() to find the address. The function name itself can them become a define which calls a function pointer. This is preferable to reimplementing the function in the SPL because it ensures we get the correct version of the function for the running kernel. This is actually pretty safe because the prototype is defined in the headers so we know we are calling the function properly. This patch also includes a rhel5 kernel patch we exports the needed symbols so we don't need to use kallsyms_lookup_name(). There are autoconf checks to detect if the symbol is exported and if so to use it directly. We should add patches for stock upstream kernels as needed if for no other reason than so we can easily track which additional symbols we needed exported. Those patches can also be used by anyone willing to rebuild their kernel, but this should not be a requirement. The rhel5 version of the export-symbols patch has been applied to the chaos kernel. Additional fixes: 1) Implement vmem_size() function using get_vmalloc_info() 2) SPL_CHECK_SYMBOL_EXPORT macro updated to use $LINUX_OBJ instead of $LINUX because Module.symvers is a build product. When $LINUX_OBJ != $LINUX we will not properly detect exported symbols. 3) SPL_LINUX_COMPILE_IFELSE macro updated to add include2 and $LINUX/include search paths to allow proper compilation when the kernel target build directory is not the source directory.
2009-02-25 21:20:40 +00:00
#ifndef _SPL_KALLSYMS_COMPAT_H
#define _SPL_KALLSYMS_COMPAT_H
#define SYMBOL_POISON ((void*)0xabcddcba)
Linux VM Integration Cleanup Remove all instances of functions being reimplemented in the SPL. When the prototypes are available in the linux headers but the function address itself is not exported use kallsyms_lookup_name() to find the address. The function name itself can them become a define which calls a function pointer. This is preferable to reimplementing the function in the SPL because it ensures we get the correct version of the function for the running kernel. This is actually pretty safe because the prototype is defined in the headers so we know we are calling the function properly. This patch also includes a rhel5 kernel patch we exports the needed symbols so we don't need to use kallsyms_lookup_name(). There are autoconf checks to detect if the symbol is exported and if so to use it directly. We should add patches for stock upstream kernels as needed if for no other reason than so we can easily track which additional symbols we needed exported. Those patches can also be used by anyone willing to rebuild their kernel, but this should not be a requirement. The rhel5 version of the export-symbols patch has been applied to the chaos kernel. Additional fixes: 1) Implement vmem_size() function using get_vmalloc_info() 2) SPL_CHECK_SYMBOL_EXPORT macro updated to use $LINUX_OBJ instead of $LINUX because Module.symvers is a build product. When $LINUX_OBJ != $LINUX we will not properly detect exported symbols. 3) SPL_LINUX_COMPILE_IFELSE macro updated to add include2 and $LINUX/include search paths to allow proper compilation when the kernel target build directory is not the source directory.
2009-02-25 21:20:40 +00:00
#ifdef HAVE_KALLSYMS_LOOKUP_NAME
#include <linux/kallsyms.h>
#define spl_kallsyms_lookup_name(name) kallsyms_lookup_name(name)
#else
extern wait_queue_head_t spl_kallsyms_lookup_name_waitq;
Linux VM Integration Cleanup Remove all instances of functions being reimplemented in the SPL. When the prototypes are available in the linux headers but the function address itself is not exported use kallsyms_lookup_name() to find the address. The function name itself can them become a define which calls a function pointer. This is preferable to reimplementing the function in the SPL because it ensures we get the correct version of the function for the running kernel. This is actually pretty safe because the prototype is defined in the headers so we know we are calling the function properly. This patch also includes a rhel5 kernel patch we exports the needed symbols so we don't need to use kallsyms_lookup_name(). There are autoconf checks to detect if the symbol is exported and if so to use it directly. We should add patches for stock upstream kernels as needed if for no other reason than so we can easily track which additional symbols we needed exported. Those patches can also be used by anyone willing to rebuild their kernel, but this should not be a requirement. The rhel5 version of the export-symbols patch has been applied to the chaos kernel. Additional fixes: 1) Implement vmem_size() function using get_vmalloc_info() 2) SPL_CHECK_SYMBOL_EXPORT macro updated to use $LINUX_OBJ instead of $LINUX because Module.symvers is a build product. When $LINUX_OBJ != $LINUX we will not properly detect exported symbols. 3) SPL_LINUX_COMPILE_IFELSE macro updated to add include2 and $LINUX/include search paths to allow proper compilation when the kernel target build directory is not the source directory.
2009-02-25 21:20:40 +00:00
typedef unsigned long (*kallsyms_lookup_name_t)(const char *);
extern kallsyms_lookup_name_t spl_kallsyms_lookup_name_fn;
#define spl_kallsyms_lookup_name(name) spl_kallsyms_lookup_name_fn(name)
#endif /* HAVE_KALLSYMS_LOOKUP_NAME */
#endif /* _SPL_KALLSYMS_COMPAT_H */