From c352e8b6de9808ec5edc792d54f8785de6626d02 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Tue, 22 Mar 2016 14:28:14 -0700 Subject: [PATCH] s390/extable: use generic search and sort routines Replace the arch specific versions of search_extable() and sort_extable() with calls to the generic ones, which now support relative exception tables as well. Signed-off-by: Ard Biesheuvel Acked-by: Heiko Carstens Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/include/asm/uaccess.h | 8 +--- arch/s390/mm/Makefile | 2 +- arch/s390/mm/extable.c | 85 --------------------------------- 3 files changed, 2 insertions(+), 93 deletions(-) delete mode 100644 arch/s390/mm/extable.c diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h index 9dd4cc47ddc7..e0900ddf91dd 100644 --- a/arch/s390/include/asm/uaccess.h +++ b/arch/s390/include/asm/uaccess.h @@ -79,18 +79,12 @@ struct exception_table_entry int insn, fixup; }; -static inline unsigned long extable_insn(const struct exception_table_entry *x) -{ - return (unsigned long)&x->insn + x->insn; -} - static inline unsigned long extable_fixup(const struct exception_table_entry *x) { return (unsigned long)&x->fixup + x->fixup; } -#define ARCH_HAS_SORT_EXTABLE -#define ARCH_HAS_SEARCH_EXTABLE +#define ARCH_HAS_RELATIVE_EXTABLE /** * __copy_from_user: - Copy a block of data from user space, with less checking. diff --git a/arch/s390/mm/Makefile b/arch/s390/mm/Makefile index 2ae54cad2b6a..0aa0ad165d8b 100644 --- a/arch/s390/mm/Makefile +++ b/arch/s390/mm/Makefile @@ -3,7 +3,7 @@ # obj-y := init.o fault.o extmem.o mmap.o vmem.o maccess.o -obj-y += page-states.o gup.o extable.o pageattr.o mem_detect.o +obj-y += page-states.o gup.o pageattr.o mem_detect.o obj-y += pgtable.o pgalloc.o obj-$(CONFIG_CMM) += cmm.o diff --git a/arch/s390/mm/extable.c b/arch/s390/mm/extable.c deleted file mode 100644 index 18c8b819b0aa..000000000000 --- a/arch/s390/mm/extable.c +++ /dev/null @@ -1,85 +0,0 @@ -#include -#include -#include - -/* - * 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) -{ - const struct exception_table_entry *mid; - unsigned long addr; - - while (first <= last) { - mid = ((last - first) >> 1) + first; - addr = extable_insn(mid); - if (addr < value) - first = mid + 1; - else if (addr > value) - last = mid - 1; - else - return mid; - } - return NULL; -} - -/* - * 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; - - /* This compare is only valid after normalization. */ - return x->insn - y->insn; -} - -void sort_extable(struct exception_table_entry *start, - struct exception_table_entry *finish) -{ - struct exception_table_entry *p; - int i; - - /* Normalize entries to being relative to the start of the section */ - for (p = start, i = 0; p < finish; p++, i += 8) { - p->insn += i; - p->fixup += i + 4; - } - sort(start, finish - start, sizeof(*start), cmp_ex, NULL); - /* Denormalize all entries */ - for (p = start, i = 0; p < finish; p++, i += 8) { - p->insn -= i; - p->fixup -= i + 4; - } -} - -#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(extable_insn(&m->extable[0]), m)) { - m->extable++; - m->num_exentries--; - } - /* Trim the end */ - while (m->num_exentries && - within_module_init(extable_insn(&m->extable[m->num_exentries-1]), m)) - m->num_exentries--; -} -#endif /* CONFIG_MODULES */