cregit-Linux how code gets into the kernel

Release 4.9 lib/extable.c

Directory: lib
/*
 * Derived from arch/ppc/mm/extable.c and arch/i386/mm/extable.c.
 *
 * Copyright (C) 2004 Paul Mackerras, IBM Corp.
 *
 * This program 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.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/sort.h>
#include <asm/uaccess.h>

#ifndef ARCH_HAS_RELATIVE_EXTABLE

#define ex_to_insn(x)	((x)->insn)
#else

static inline unsigned long ex_to_insn(const struct exception_table_entry *x) { return (unsigned long)&x->insn + x->insn; }

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ard biesheuvelard biesheuvel28100.00%1100.00%
Total28100.00%1100.00%

#endif #ifndef ARCH_HAS_SORT_EXTABLE #ifndef ARCH_HAS_RELATIVE_EXTABLE #define swap_ex NULL #else
static void swap_ex(void *a, void *b, int size) { struct exception_table_entry *x = a, *y = b, tmp; int delta = b - a; tmp = *x; x->insn = y->insn + delta; y->insn = tmp.insn - delta; #ifdef swap_ex_entry_fixup swap_ex_entry_fixup(x, y, tmp, delta); #else x->fixup = y->fixup + delta; y->fixup = tmp.fixup - delta; #endif }

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ard biesheuvelard biesheuvel101100.00%1100.00%
Total101100.00%1100.00%

#endif /* ARCH_HAS_RELATIVE_EXTABLE */ /* * The exception table needs to be sorted so that the binary * search that we use to find entries in it works properly. * This is used both for the kernel exception table and for * the exception tables of modules that get loaded. */
static int cmp_ex(const void *a, const void *b) { const struct exception_table_entry *x = a, *y = b; /* avoid overflow */ if (ex_to_insn(x) > ex_to_insn(y)) return 1; if (ex_to_insn(x) < ex_to_insn(y)) return -1; return 0; }

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matt mackallmatt mackall5281.25%266.67%
ard biesheuvelard biesheuvel1218.75%133.33%
Total64100.00%3100.00%


void sort_extable(struct exception_table_entry *start, struct exception_table_entry *finish) { sort(start, finish - start, sizeof(struct exception_table_entry), cmp_ex, swap_ex); }

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pre-gitpre-git1955.88%125.00%
matt mackallmatt mackall1338.24%125.00%
paul mackerraspaul mackerras12.94%125.00%
ard biesheuvelard biesheuvel12.94%125.00%
Total34100.00%4100.00%

#ifdef CONFIG_MODULES /* * If the exception table is sorted, any referring to the module init * will be at the beginning or the end. */
void trim_init_extable(struct module *m) { /*trim the beginning*/ while (m->num_exentries && within_module_init(ex_to_insn(&m->extable[0]), m)) { m->extable++; m->num_exentries--; } /*trim the end*/ while (m->num_exentries && within_module_init(ex_to_insn(&m->extable[m->num_exentries - 1]), m)) m->num_exentries--; }

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rusty russellrusty russell6989.61%150.00%
ard biesheuvelard biesheuvel810.39%150.00%
Total77100.00%2100.00%

#endif /* CONFIG_MODULES */ #endif /* !ARCH_HAS_SORT_EXTABLE */ #ifndef ARCH_HAS_SEARCH_EXTABLE /* * Search one exception table for an entry corresponding to the * given instruction address, and return the address of the entry, * or NULL if none is found. * We use a binary search, and thus we assume that the table is * already sorted. */
const struct exception_table_entry * search_extable(const struct exception_table_entry *first, const struct exception_table_entry *last, unsigned long value) { while (first <= last) { const struct exception_table_entry *mid; mid = ((last - first) >> 1) + first; /* * careful, the distance between value and insn * can be larger than MAX_LONG: */ if (ex_to_insn(mid) < value) first = mid + 1; else if (ex_to_insn(mid) > value) last = mid - 1; else return mid; } return NULL; }

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PersonTokensPropCommitsCommitProp
pre-gitpre-git6268.13%342.86%
andrew mortonandrew morton1213.19%114.29%
rusty russellrusty russell66.59%114.29%
ard biesheuvelard biesheuvel66.59%114.29%
eric dumazeteric dumazet55.49%114.29%
Total91100.00%7100.00%

#endif

Overall Contributors

PersonTokensPropCommitsCommitProp
ard biesheuvelard biesheuvel18240.09%17.14%
pre-gitpre-git8719.16%428.57%
rusty russellrusty russell8618.94%214.29%
matt mackallmatt mackall6814.98%214.29%
andrew mortonandrew morton224.85%214.29%
eric dumazeteric dumazet51.10%17.14%
paul mackerraspaul mackerras30.66%17.14%
jon masonjon mason10.22%17.14%
Total454100.00%14100.00%
Directory: lib