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Subject[PATCH v2 5/6] ia64/extable: use generic search and sort routines
Date
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.

Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
arch/ia64/include/asm/uaccess.h | 8 +-
arch/ia64/mm/extable.c | 97 +-------------------
2 files changed, 4 insertions(+), 101 deletions(-)

diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 4f3fb6ccbf21..2189d5ddc1ee 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -341,13 +341,11 @@ extern unsigned long __strnlen_user (const char __user *, long);
__su_ret; \
})

-/* Generic code can't deal with the location-relative format that we use for compactness. */
-#define ARCH_HAS_SORT_EXTABLE
-#define ARCH_HAS_SEARCH_EXTABLE
+#define ARCH_HAS_RELATIVE_EXTABLE

struct exception_table_entry {
- int addr; /* location-relative address of insn this fixup is for */
- int cont; /* location-relative continuation addr.; if bit 2 is set, r9 is set to 0 */
+ int insn; /* location-relative address of insn this fixup is for */
+ int fixup; /* location-relative continuation addr.; if bit 2 is set, r9 is set to 0 */
};

extern void ia64_handle_exception (struct pt_regs *regs, const struct exception_table_entry *e);
diff --git a/arch/ia64/mm/extable.c b/arch/ia64/mm/extable.c
index c99a41e29fe8..8f70bb2d0c37 100644
--- a/arch/ia64/mm/extable.c
+++ b/arch/ia64/mm/extable.c
@@ -5,107 +5,12 @@
* David Mosberger-Tang <davidm@hpl.hp.com>
*/

-#include <linux/sort.h>
-
#include <asm/uaccess.h>
-#include <linux/module.h>
-
-static int cmp_ex(const void *a, const void *b)
-{
- const struct exception_table_entry *l = a, *r = b;
- u64 lip = (u64) &l->addr + l->addr;
- u64 rip = (u64) &r->addr + r->addr;
-
- /* avoid overflow */
- if (lip > rip)
- return 1;
- if (lip < rip)
- return -1;
- return 0;
-}
-
-static void swap_ex(void *a, void *b, int size)
-{
- struct exception_table_entry *l = a, *r = b, tmp;
- u64 delta = (u64) r - (u64) l;
-
- tmp = *l;
- l->addr = r->addr + delta;
- l->cont = r->cont + delta;
- r->addr = tmp.addr - delta;
- r->cont = tmp.cont - delta;
-}
-
-/*
- * Sort the exception table. It's usually already sorted, but there
- * may be unordered entries due to multiple text sections (such as the
- * .init text section). Note that the exception-table-entries contain
- * location-relative addresses, which requires a bit of care during
- * sorting to avoid overflows in the offset members (e.g., it would
- * not be safe to make a temporary copy of an exception-table entry on
- * the stack, because the stack may be more than 2GB away from the
- * exception-table).
- */
-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);
-}
-
-static inline unsigned long ex_to_addr(const struct exception_table_entry *x)
-{
- return (unsigned long)&x->addr + x->addr;
-}
-
-#ifdef CONFIG_MODULES
-/*
- * Any entry 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_addr(&m->extable[0]), m)) {
- m->extable++;
- m->num_exentries--;
- }
- /*trim the end*/
- while (m->num_exentries &&
- within_module_init(ex_to_addr(&m->extable[m->num_exentries-1]),
- m))
- m->num_exentries--;
-}
-#endif /* CONFIG_MODULES */
-
-const struct exception_table_entry *
-search_extable (const struct exception_table_entry *first,
- const struct exception_table_entry *last,
- unsigned long ip)
-{
- const struct exception_table_entry *mid;
- unsigned long mid_ip;
- long diff;
-
- while (first <= last) {
- mid = &first[(last - first)/2];
- mid_ip = (u64) &mid->addr + mid->addr;
- diff = mid_ip - ip;
- if (diff == 0)
- return mid;
- else if (diff < 0)
- first = mid + 1;
- else
- last = mid - 1;
- }
- return NULL;
-}

void
ia64_handle_exception (struct pt_regs *regs, const struct exception_table_entry *e)
{
- long fix = (u64) &e->cont + e->cont;
+ long fix = (u64) &e->fixup + e->fixup;

regs->r8 = -EFAULT;
if (fix & 4)
--
2.5.0


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