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Diffstat (limited to 'arch/hexagon/mm/copy_from_user.S')
-rw-r--r-- | arch/hexagon/mm/copy_from_user.S | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/arch/hexagon/mm/copy_from_user.S b/arch/hexagon/mm/copy_from_user.S new file mode 100644 index 0000000000..1a49bf24f6 --- /dev/null +++ b/arch/hexagon/mm/copy_from_user.S @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * User memory copy functions for kernel + * + * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. + */ + +/* + * The right way to do this involves valignb + * The easy way to do this is only speed up src/dest similar alignment. + */ + +/* + * Copy to/from user are the same, except that for packets with a load and + * a store, I don't know how to tell which kind of exception we got. + * Therefore, we duplicate the function, and handle faulting addresses + * differently for each function + */ + +/* + * copy from user: loads can fault + */ +#define src_sav r13 +#define dst_sav r12 +#define src_dst_sav r13:12 +#define d_dbuf r15:14 +#define w_dbuf r15 + +#define dst r0 +#define src r1 +#define bytes r2 +#define loopcount r5 + +#define FUNCNAME raw_copy_from_user +#include "copy_user_template.S" + + /* LOAD FAULTS from COPY_FROM_USER */ + + /* Alignment loop. r2 has been updated. Return it. */ + .falign +1009: +2009: +4009: + { + r0 = r2 + jumpr r31 + } + /* Normal copy loops. Do epilog. Use src-src_sav to compute distance */ + /* X - (A - B) == X + B - A */ + .falign +8089: + { + memd(dst) = d_dbuf + r2 += sub(src_sav,src) + } + { + r0 = r2 + jumpr r31 + } + .falign +4089: + { + memw(dst) = w_dbuf + r2 += sub(src_sav,src) + } + { + r0 = r2 + jumpr r31 + } + .falign +2089: + { + memh(dst) = w_dbuf + r2 += sub(src_sav,src) + } + { + r0 = r2 + jumpr r31 + } + .falign +1089: + { + memb(dst) = w_dbuf + r2 += sub(src_sav,src) + } + { + r0 = r2 + jumpr r31 + } + + /* COPY FROM USER: only loads can fail */ + + .section __ex_table,"a" + .long 1000b,1009b + .long 2000b,2009b + .long 4000b,4009b + .long 8080b,8089b + .long 4080b,4089b + .long 2080b,2089b + .long 1080b,1089b + .previous |