diff options
Diffstat (limited to 'arch/sparc64/mm/extable.c')
-rw-r--r-- | arch/sparc64/mm/extable.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/sparc64/mm/extable.c b/arch/sparc64/mm/extable.c new file mode 100644 index 000000000000..ec334297ff4f --- /dev/null +++ b/arch/sparc64/mm/extable.c @@ -0,0 +1,80 @@ +/* + * linux/arch/sparc64/mm/extable.c + */ + +#include <linux/config.h> +#include <linux/module.h> +#include <asm/uaccess.h> + +extern const struct exception_table_entry __start___ex_table[]; +extern const struct exception_table_entry __stop___ex_table[]; + +void sort_extable(struct exception_table_entry *start, + struct exception_table_entry *finish) +{ +} + +/* Caller knows they are in a range if ret->fixup == 0 */ +const struct exception_table_entry * +search_extable(const struct exception_table_entry *start, + const struct exception_table_entry *last, + unsigned long value) +{ + const struct exception_table_entry *walk; + + /* Single insn entries are encoded as: + * word 1: insn address + * word 2: fixup code address + * + * Range entries are encoded as: + * word 1: first insn address + * word 2: 0 + * word 3: last insn address + 4 bytes + * word 4: fixup code address + * + * See asm/uaccess.h for more details. + */ + + /* 1. Try to find an exact match. */ + for (walk = start; walk <= last; walk++) { + if (walk->fixup == 0) { + /* A range entry, skip both parts. */ + walk++; + continue; + } + + if (walk->insn == value) + return walk; + } + + /* 2. Try to find a range match. */ + for (walk = start; walk <= (last - 1); walk++) { + if (walk->fixup) + continue; + + if (walk[0].insn <= value && walk[1].insn > value) + return walk; + + walk++; + } + + return NULL; +} + +/* Special extable search, which handles ranges. Returns fixup */ +unsigned long search_extables_range(unsigned long addr, unsigned long *g2) +{ + const struct exception_table_entry *entry; + + entry = search_exception_tables(addr); + if (!entry) + return 0; + + /* Inside range? Fix g2 and return correct fixup */ + if (!entry->fixup) { + *g2 = (addr - entry->insn) / 4; + return (entry + 1)->fixup; + } + + return entry->fixup; +} |