diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-01-29 08:52:50 +1100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-01-29 08:52:50 +1100 |
commit | e189f3495c4e30fc84fc9241096edf3932e23439 (patch) | |
tree | 5916c89ace81537a02ae01869386ba6caafdab9c /arch/sh/mm/extable_64.c | |
parent | f4798748dee00c807a63f5518f08b3df161e0f6d (diff) | |
parent | 6582d7b7376aa587d74b08c74457dc28abc1a9fa (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (197 commits)
sh: add spi header and r2d platform data V3
sh: update r7780rp interrupt code
sh: remove consistent alloc stuff from the machine vector
sh: use declared coherent memory for dreamcast pci ethernet adapter
sh: declared coherent memory support V2
sh: Add support for SDK7780 board.
sh: constify function pointer tables
sh: Kill off -traditional for linker script.
cdrom: Add support for Sega Dreamcast GD-ROM.
sh: Kill off hs7751rvoip reference from arch/sh/Kconfig.
sh: Drop r7780rp_defconfig, use r7780mp_defconfig as kbuild default.
sh: Kill off dead HS771RVoIP board support.
sh: r7785rp: Fix up DECLARE_INTC_DESC() arg mismatch.
sh: r7785rp: Hook up the rest of the HL7785 FPGA IRQ vectors.
sh: r2d - enable sm501 usb host function
sh: remove voyagergx
sh: r2d - add lcd planel timings to sm501 platform data
sh: Add OHCI and UDC platform devices for SH7720.
sh: intc - remove default interrupt priority tables
sh: Correct pte size mismatch for X2 TLB.
...
Diffstat (limited to 'arch/sh/mm/extable_64.c')
-rw-r--r-- | arch/sh/mm/extable_64.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/arch/sh/mm/extable_64.c b/arch/sh/mm/extable_64.c new file mode 100644 index 00000000000..f05499688d8 --- /dev/null +++ b/arch/sh/mm/extable_64.c @@ -0,0 +1,82 @@ +/* + * arch/sh/mm/extable_64.c + * + * Copyright (C) 2003 Richard Curnow + * Copyright (C) 2003, 2004 Paul Mundt + * + * Cloned from the 2.5 SH version.. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include <linux/rwsem.h> +#include <linux/module.h> +#include <asm/uaccess.h> + +extern unsigned long copy_user_memcpy, copy_user_memcpy_end; +extern void __copy_user_fixup(void); + +static const struct exception_table_entry __copy_user_fixup_ex = { + .fixup = (unsigned long)&__copy_user_fixup, +}; + +/* + * Some functions that may trap due to a bad user-mode address have too + * many loads and stores in them to make it at all practical to label + * each one and put them all in the main exception table. + * + * In particular, the fast memcpy routine is like this. It's fix-up is + * just to fall back to a slow byte-at-a-time copy, which is handled the + * conventional way. So it's functionally OK to just handle any trap + * occurring in the fast memcpy with that fixup. + */ +static const struct exception_table_entry *check_exception_ranges(unsigned long addr) +{ + if ((addr >= (unsigned long)©_user_memcpy) && + (addr <= (unsigned long)©_user_memcpy_end)) + return &__copy_user_fixup_ex; + + return NULL; +} + +/* Simple binary search */ +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; + + mid = check_exception_ranges(value); + if (mid) + return mid; + + while (first <= last) { + long diff; + + mid = (last - first) / 2 + first; + diff = mid->insn - value; + if (diff == 0) + return mid; + else if (diff < 0) + first = mid+1; + else + last = mid-1; + } + + return NULL; +} + +int fixup_exception(struct pt_regs *regs) +{ + const struct exception_table_entry *fixup; + + fixup = search_exception_tables(regs->pc); + if (fixup) { + regs->pc = fixup->fixup; + return 1; + } + + return 0; +} |