mirror_zfs/include/linux/kallsyms_compat.h

#ifndef _SPL_KALLSYMS_COMPAT_H
#define _SPL_KALLSYMS_COMPAT_H

#define SYMBOL_POISON ((void*)0xabcddcba)

#ifdef HAVE_KALLSYMS_LOOKUP_NAME

#include <linux/kallsyms.h>
#define spl_kallsyms_lookup_name(name) kallsyms_lookup_name(name)

#else

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 */
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. 2009-02-26 00:20:40 +03:00			`#ifndef _SPL_KALLSYMS_COMPAT_H`
			`#define _SPL_KALLSYMS_COMPAT_H`

SLES10 Fixes (part 2): - Configure check, the div64_64() function was renamed to div64_u64() as of 2.6.26. - Configure check, the global_page_state() fuction was introduced in 2.6.18 kernels. The earlier 2.6.16 based SLES10 must not try and use it, thankfully get_zone_counts() is still available. - To simplify debugging poison all symbols aquired dynamically using spl_kallsyms_lookup_name() with SYMBOL_POISON. - Add console messages when the user mode helpers fail. - spl_kmem_init_globals() use bit shifts instead of division. - When the monotonic clock is unavailable __gethrtime() must perform the HZ division as an 'unsigned long long' because the SPL only implements __udivdi3(), and not __divdi3() for 'long long' division on 32-bit arches. 2009-05-20 21:08:37 +04:00			`#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. 2009-02-26 00:20:40 +03:00			`#ifdef HAVE_KALLSYMS_LOOKUP_NAME`

			`#include <linux/kallsyms.h>`
			`#define spl_kallsyms_lookup_name(name) kallsyms_lookup_name(name)`

			`#else`

			`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 */`