diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 17:35:05 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 17:39:31 +0000 |
commit | 85c675d0d09a45a135bddd15d7b385f8758c32fb (patch) | |
tree | 76267dbc9b9a130337be3640948fe397b04ac629 /arch/ia64/lib/memcpy_mck.S | |
parent | Adding upstream version 6.6.15. (diff) | |
download | linux-85c675d0d09a45a135bddd15d7b385f8758c32fb.tar.xz linux-85c675d0d09a45a135bddd15d7b385f8758c32fb.zip |
Adding upstream version 6.7.7.upstream/6.7.7
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/ia64/lib/memcpy_mck.S')
-rw-r--r-- | arch/ia64/lib/memcpy_mck.S | 659 |
1 files changed, 0 insertions, 659 deletions
diff --git a/arch/ia64/lib/memcpy_mck.S b/arch/ia64/lib/memcpy_mck.S deleted file mode 100644 index c0d4362217..0000000000 --- a/arch/ia64/lib/memcpy_mck.S +++ /dev/null @@ -1,659 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * Itanium 2-optimized version of memcpy and copy_user function - * - * Inputs: - * in0: destination address - * in1: source address - * in2: number of bytes to copy - * Output: - * for memcpy: return dest - * for copy_user: return 0 if success, - * or number of byte NOT copied if error occurred. - * - * Copyright (C) 2002 Intel Corp. - * Copyright (C) 2002 Ken Chen <kenneth.w.chen@intel.com> - */ -#include <linux/export.h> -#include <asm/asmmacro.h> -#include <asm/page.h> - -#define EK(y...) EX(y) - -/* McKinley specific optimization */ - -#define retval r8 -#define saved_pfs r31 -#define saved_lc r10 -#define saved_pr r11 -#define saved_in0 r14 -#define saved_in1 r15 -#define saved_in2 r16 - -#define src0 r2 -#define src1 r3 -#define dst0 r17 -#define dst1 r18 -#define cnt r9 - -/* r19-r30 are temp for each code section */ -#define PREFETCH_DIST 8 -#define src_pre_mem r19 -#define dst_pre_mem r20 -#define src_pre_l2 r21 -#define dst_pre_l2 r22 -#define t1 r23 -#define t2 r24 -#define t3 r25 -#define t4 r26 -#define t5 t1 // alias! -#define t6 t2 // alias! -#define t7 t3 // alias! -#define n8 r27 -#define t9 t5 // alias! -#define t10 t4 // alias! -#define t11 t7 // alias! -#define t12 t6 // alias! -#define t14 t10 // alias! -#define t13 r28 -#define t15 r29 -#define tmp r30 - -/* defines for long_copy block */ -#define A 0 -#define B (PREFETCH_DIST) -#define C (B + PREFETCH_DIST) -#define D (C + 1) -#define N (D + 1) -#define Nrot ((N + 7) & ~7) - -/* alias */ -#define in0 r32 -#define in1 r33 -#define in2 r34 - -GLOBAL_ENTRY(memcpy) - and r28=0x7,in0 - and r29=0x7,in1 - mov f6=f0 - mov retval=in0 - br.cond.sptk .common_code - ;; -END(memcpy) -EXPORT_SYMBOL(memcpy) -GLOBAL_ENTRY(__copy_user) - .prologue -// check dest alignment - and r28=0x7,in0 - and r29=0x7,in1 - mov f6=f1 - mov saved_in0=in0 // save dest pointer - mov saved_in1=in1 // save src pointer - mov retval=r0 // initialize return value - ;; -.common_code: - cmp.gt p15,p0=8,in2 // check for small size - cmp.ne p13,p0=0,r28 // check dest alignment - cmp.ne p14,p0=0,r29 // check src alignment - add src0=0,in1 - sub r30=8,r28 // for .align_dest - mov saved_in2=in2 // save len - ;; - add dst0=0,in0 - add dst1=1,in0 // dest odd index - cmp.le p6,p0 = 1,r30 // for .align_dest -(p15) br.cond.dpnt .memcpy_short -(p13) br.cond.dpnt .align_dest -(p14) br.cond.dpnt .unaligned_src - ;; - -// both dest and src are aligned on 8-byte boundary -.aligned_src: - .save ar.pfs, saved_pfs - alloc saved_pfs=ar.pfs,3,Nrot-3,0,Nrot - .save pr, saved_pr - mov saved_pr=pr - - shr.u cnt=in2,7 // this much cache line - ;; - cmp.lt p6,p0=2*PREFETCH_DIST,cnt - cmp.lt p7,p8=1,cnt - .save ar.lc, saved_lc - mov saved_lc=ar.lc - .body - add cnt=-1,cnt - add src_pre_mem=0,in1 // prefetch src pointer - add dst_pre_mem=0,in0 // prefetch dest pointer - ;; -(p7) mov ar.lc=cnt // prefetch count -(p8) mov ar.lc=r0 -(p6) br.cond.dpnt .long_copy - ;; - -.prefetch: - lfetch.fault [src_pre_mem], 128 - lfetch.fault.excl [dst_pre_mem], 128 - br.cloop.dptk.few .prefetch - ;; - -.medium_copy: - and tmp=31,in2 // copy length after iteration - shr.u r29=in2,5 // number of 32-byte iteration - add dst1=8,dst0 // 2nd dest pointer - ;; - add cnt=-1,r29 // ctop iteration adjustment - cmp.eq p10,p0=r29,r0 // do we really need to loop? - add src1=8,src0 // 2nd src pointer - cmp.le p6,p0=8,tmp - ;; - cmp.le p7,p0=16,tmp - mov ar.lc=cnt // loop setup - cmp.eq p16,p17 = r0,r0 - mov ar.ec=2 -(p10) br.dpnt.few .aligned_src_tail - ;; - TEXT_ALIGN(32) -1: -EX(.ex_handler, (p16) ld8 r34=[src0],16) -EK(.ex_handler, (p16) ld8 r38=[src1],16) -EX(.ex_handler, (p17) st8 [dst0]=r33,16) -EK(.ex_handler, (p17) st8 [dst1]=r37,16) - ;; -EX(.ex_handler, (p16) ld8 r32=[src0],16) -EK(.ex_handler, (p16) ld8 r36=[src1],16) -EX(.ex_handler, (p16) st8 [dst0]=r34,16) -EK(.ex_handler, (p16) st8 [dst1]=r38,16) - br.ctop.dptk.few 1b - ;; - -.aligned_src_tail: -EX(.ex_handler, (p6) ld8 t1=[src0]) - mov ar.lc=saved_lc - mov ar.pfs=saved_pfs -EX(.ex_hndlr_s, (p7) ld8 t2=[src1],8) - cmp.le p8,p0=24,tmp - and r21=-8,tmp - ;; -EX(.ex_hndlr_s, (p8) ld8 t3=[src1]) -EX(.ex_handler, (p6) st8 [dst0]=t1) // store byte 1 - and in2=7,tmp // remaining length -EX(.ex_hndlr_d, (p7) st8 [dst1]=t2,8) // store byte 2 - add src0=src0,r21 // setting up src pointer - add dst0=dst0,r21 // setting up dest pointer - ;; -EX(.ex_handler, (p8) st8 [dst1]=t3) // store byte 3 - mov pr=saved_pr,-1 - br.dptk.many .memcpy_short - ;; - -/* code taken from copy_page_mck */ -.long_copy: - .rotr v[2*PREFETCH_DIST] - .rotp p[N] - - mov src_pre_mem = src0 - mov pr.rot = 0x10000 - mov ar.ec = 1 // special unrolled loop - - mov dst_pre_mem = dst0 - - add src_pre_l2 = 8*8, src0 - add dst_pre_l2 = 8*8, dst0 - ;; - add src0 = 8, src_pre_mem // first t1 src - mov ar.lc = 2*PREFETCH_DIST - 1 - shr.u cnt=in2,7 // number of lines - add src1 = 3*8, src_pre_mem // first t3 src - add dst0 = 8, dst_pre_mem // first t1 dst - add dst1 = 3*8, dst_pre_mem // first t3 dst - ;; - and tmp=127,in2 // remaining bytes after this block - add cnt = -(2*PREFETCH_DIST) - 1, cnt - // same as .line_copy loop, but with all predicated-off instructions removed: -.prefetch_loop: -EX(.ex_hndlr_lcpy_1, (p[A]) ld8 v[A] = [src_pre_mem], 128) // M0 -EK(.ex_hndlr_lcpy_1, (p[B]) st8 [dst_pre_mem] = v[B], 128) // M2 - br.ctop.sptk .prefetch_loop - ;; - cmp.eq p16, p0 = r0, r0 // reset p16 to 1 - mov ar.lc = cnt - mov ar.ec = N // # of stages in pipeline - ;; -.line_copy: -EX(.ex_handler, (p[D]) ld8 t2 = [src0], 3*8) // M0 -EK(.ex_handler, (p[D]) ld8 t4 = [src1], 3*8) // M1 -EX(.ex_handler_lcpy, (p[B]) st8 [dst_pre_mem] = v[B], 128) // M2 prefetch dst from memory -EK(.ex_handler_lcpy, (p[D]) st8 [dst_pre_l2] = n8, 128) // M3 prefetch dst from L2 - ;; -EX(.ex_handler_lcpy, (p[A]) ld8 v[A] = [src_pre_mem], 128) // M0 prefetch src from memory -EK(.ex_handler_lcpy, (p[C]) ld8 n8 = [src_pre_l2], 128) // M1 prefetch src from L2 -EX(.ex_handler, (p[D]) st8 [dst0] = t1, 8) // M2 -EK(.ex_handler, (p[D]) st8 [dst1] = t3, 8) // M3 - ;; -EX(.ex_handler, (p[D]) ld8 t5 = [src0], 8) -EK(.ex_handler, (p[D]) ld8 t7 = [src1], 3*8) -EX(.ex_handler, (p[D]) st8 [dst0] = t2, 3*8) -EK(.ex_handler, (p[D]) st8 [dst1] = t4, 3*8) - ;; -EX(.ex_handler, (p[D]) ld8 t6 = [src0], 3*8) -EK(.ex_handler, (p[D]) ld8 t10 = [src1], 8) -EX(.ex_handler, (p[D]) st8 [dst0] = t5, 8) -EK(.ex_handler, (p[D]) st8 [dst1] = t7, 3*8) - ;; -EX(.ex_handler, (p[D]) ld8 t9 = [src0], 3*8) -EK(.ex_handler, (p[D]) ld8 t11 = [src1], 3*8) -EX(.ex_handler, (p[D]) st8 [dst0] = t6, 3*8) -EK(.ex_handler, (p[D]) st8 [dst1] = t10, 8) - ;; -EX(.ex_handler, (p[D]) ld8 t12 = [src0], 8) -EK(.ex_handler, (p[D]) ld8 t14 = [src1], 8) -EX(.ex_handler, (p[D]) st8 [dst0] = t9, 3*8) -EK(.ex_handler, (p[D]) st8 [dst1] = t11, 3*8) - ;; -EX(.ex_handler, (p[D]) ld8 t13 = [src0], 4*8) -EK(.ex_handler, (p[D]) ld8 t15 = [src1], 4*8) -EX(.ex_handler, (p[D]) st8 [dst0] = t12, 8) -EK(.ex_handler, (p[D]) st8 [dst1] = t14, 8) - ;; -EX(.ex_handler, (p[C]) ld8 t1 = [src0], 8) -EK(.ex_handler, (p[C]) ld8 t3 = [src1], 8) -EX(.ex_handler, (p[D]) st8 [dst0] = t13, 4*8) -EK(.ex_handler, (p[D]) st8 [dst1] = t15, 4*8) - br.ctop.sptk .line_copy - ;; - - add dst0=-8,dst0 - add src0=-8,src0 - mov in2=tmp - .restore sp - br.sptk.many .medium_copy - ;; - -#define BLOCK_SIZE 128*32 -#define blocksize r23 -#define curlen r24 - -// dest is on 8-byte boundary, src is not. We need to do -// ld8-ld8, shrp, then st8. Max 8 byte copy per cycle. -.unaligned_src: - .prologue - .save ar.pfs, saved_pfs - alloc saved_pfs=ar.pfs,3,5,0,8 - .save ar.lc, saved_lc - mov saved_lc=ar.lc - .save pr, saved_pr - mov saved_pr=pr - .body -.4k_block: - mov saved_in0=dst0 // need to save all input arguments - mov saved_in2=in2 - mov blocksize=BLOCK_SIZE - ;; - cmp.lt p6,p7=blocksize,in2 - mov saved_in1=src0 - ;; -(p6) mov in2=blocksize - ;; - shr.u r21=in2,7 // this much cache line - shr.u r22=in2,4 // number of 16-byte iteration - and curlen=15,in2 // copy length after iteration - and r30=7,src0 // source alignment - ;; - cmp.lt p7,p8=1,r21 - add cnt=-1,r21 - ;; - - add src_pre_mem=0,src0 // prefetch src pointer - add dst_pre_mem=0,dst0 // prefetch dest pointer - and src0=-8,src0 // 1st src pointer -(p7) mov ar.lc = cnt -(p8) mov ar.lc = r0 - ;; - TEXT_ALIGN(32) -1: lfetch.fault [src_pre_mem], 128 - lfetch.fault.excl [dst_pre_mem], 128 - br.cloop.dptk.few 1b - ;; - - shladd dst1=r22,3,dst0 // 2nd dest pointer - shladd src1=r22,3,src0 // 2nd src pointer - cmp.eq p8,p9=r22,r0 // do we really need to loop? - cmp.le p6,p7=8,curlen; // have at least 8 byte remaining? - add cnt=-1,r22 // ctop iteration adjustment - ;; -EX(.ex_handler, (p9) ld8 r33=[src0],8) // loop primer -EK(.ex_handler, (p9) ld8 r37=[src1],8) -(p8) br.dpnt.few .noloop - ;; - -// The jump address is calculated based on src alignment. The COPYU -// macro below need to confine its size to power of two, so an entry -// can be caulated using shl instead of an expensive multiply. The -// size is then hard coded by the following #define to match the -// actual size. This make it somewhat tedious when COPYU macro gets -// changed and this need to be adjusted to match. -#define LOOP_SIZE 6 -1: - mov r29=ip // jmp_table thread - mov ar.lc=cnt - ;; - add r29=.jump_table - 1b - (.jmp1-.jump_table), r29 - shl r28=r30, LOOP_SIZE // jmp_table thread - mov ar.ec=2 // loop setup - ;; - add r29=r29,r28 // jmp_table thread - cmp.eq p16,p17=r0,r0 - ;; - mov b6=r29 // jmp_table thread - ;; - br.cond.sptk.few b6 - -// for 8-15 byte case -// We will skip the loop, but need to replicate the side effect -// that the loop produces. -.noloop: -EX(.ex_handler, (p6) ld8 r37=[src1],8) - add src0=8,src0 -(p6) shl r25=r30,3 - ;; -EX(.ex_handler, (p6) ld8 r27=[src1]) -(p6) shr.u r28=r37,r25 -(p6) sub r26=64,r25 - ;; -(p6) shl r27=r27,r26 - ;; -(p6) or r21=r28,r27 - -.unaligned_src_tail: -/* check if we have more than blocksize to copy, if so go back */ - cmp.gt p8,p0=saved_in2,blocksize - ;; -(p8) add dst0=saved_in0,blocksize -(p8) add src0=saved_in1,blocksize -(p8) sub in2=saved_in2,blocksize -(p8) br.dpnt .4k_block - ;; - -/* we have up to 15 byte to copy in the tail. - * part of work is already done in the jump table code - * we are at the following state. - * src side: - * - * xxxxxx xx <----- r21 has xxxxxxxx already - * -------- -------- -------- - * 0 8 16 - * ^ - * | - * src1 - * - * dst - * -------- -------- -------- - * ^ - * | - * dst1 - */ -EX(.ex_handler, (p6) st8 [dst1]=r21,8) // more than 8 byte to copy -(p6) add curlen=-8,curlen // update length - mov ar.pfs=saved_pfs - ;; - mov ar.lc=saved_lc - mov pr=saved_pr,-1 - mov in2=curlen // remaining length - mov dst0=dst1 // dest pointer - add src0=src1,r30 // forward by src alignment - ;; - -// 7 byte or smaller. -.memcpy_short: - cmp.le p8,p9 = 1,in2 - cmp.le p10,p11 = 2,in2 - cmp.le p12,p13 = 3,in2 - cmp.le p14,p15 = 4,in2 - add src1=1,src0 // second src pointer - add dst1=1,dst0 // second dest pointer - ;; - -EX(.ex_handler_short, (p8) ld1 t1=[src0],2) -EK(.ex_handler_short, (p10) ld1 t2=[src1],2) -(p9) br.ret.dpnt rp // 0 byte copy - ;; - -EX(.ex_handler_short, (p8) st1 [dst0]=t1,2) -EK(.ex_handler_short, (p10) st1 [dst1]=t2,2) -(p11) br.ret.dpnt rp // 1 byte copy - -EX(.ex_handler_short, (p12) ld1 t3=[src0],2) -EK(.ex_handler_short, (p14) ld1 t4=[src1],2) -(p13) br.ret.dpnt rp // 2 byte copy - ;; - - cmp.le p6,p7 = 5,in2 - cmp.le p8,p9 = 6,in2 - cmp.le p10,p11 = 7,in2 - -EX(.ex_handler_short, (p12) st1 [dst0]=t3,2) -EK(.ex_handler_short, (p14) st1 [dst1]=t4,2) -(p15) br.ret.dpnt rp // 3 byte copy - ;; - -EX(.ex_handler_short, (p6) ld1 t5=[src0],2) -EK(.ex_handler_short, (p8) ld1 t6=[src1],2) -(p7) br.ret.dpnt rp // 4 byte copy - ;; - -EX(.ex_handler_short, (p6) st1 [dst0]=t5,2) -EK(.ex_handler_short, (p8) st1 [dst1]=t6,2) -(p9) br.ret.dptk rp // 5 byte copy - -EX(.ex_handler_short, (p10) ld1 t7=[src0],2) -(p11) br.ret.dptk rp // 6 byte copy - ;; - -EX(.ex_handler_short, (p10) st1 [dst0]=t7,2) - br.ret.dptk rp // done all cases - - -/* Align dest to nearest 8-byte boundary. We know we have at - * least 7 bytes to copy, enough to crawl to 8-byte boundary. - * Actual number of byte to crawl depend on the dest alignment. - * 7 byte or less is taken care at .memcpy_short - - * src0 - source even index - * src1 - source odd index - * dst0 - dest even index - * dst1 - dest odd index - * r30 - distance to 8-byte boundary - */ - -.align_dest: - add src1=1,in1 // source odd index - cmp.le p7,p0 = 2,r30 // for .align_dest - cmp.le p8,p0 = 3,r30 // for .align_dest -EX(.ex_handler_short, (p6) ld1 t1=[src0],2) - cmp.le p9,p0 = 4,r30 // for .align_dest - cmp.le p10,p0 = 5,r30 - ;; -EX(.ex_handler_short, (p7) ld1 t2=[src1],2) -EK(.ex_handler_short, (p8) ld1 t3=[src0],2) - cmp.le p11,p0 = 6,r30 -EX(.ex_handler_short, (p6) st1 [dst0] = t1,2) - cmp.le p12,p0 = 7,r30 - ;; -EX(.ex_handler_short, (p9) ld1 t4=[src1],2) -EK(.ex_handler_short, (p10) ld1 t5=[src0],2) -EX(.ex_handler_short, (p7) st1 [dst1] = t2,2) -EK(.ex_handler_short, (p8) st1 [dst0] = t3,2) - ;; -EX(.ex_handler_short, (p11) ld1 t6=[src1],2) -EK(.ex_handler_short, (p12) ld1 t7=[src0],2) - cmp.eq p6,p7=r28,r29 -EX(.ex_handler_short, (p9) st1 [dst1] = t4,2) -EK(.ex_handler_short, (p10) st1 [dst0] = t5,2) - sub in2=in2,r30 - ;; -EX(.ex_handler_short, (p11) st1 [dst1] = t6,2) -EK(.ex_handler_short, (p12) st1 [dst0] = t7) - add dst0=in0,r30 // setup arguments - add src0=in1,r30 -(p6) br.cond.dptk .aligned_src -(p7) br.cond.dpnt .unaligned_src - ;; - -/* main loop body in jump table format */ -#define COPYU(shift) \ -1: \ -EX(.ex_handler, (p16) ld8 r32=[src0],8); /* 1 */ \ -EK(.ex_handler, (p16) ld8 r36=[src1],8); \ - (p17) shrp r35=r33,r34,shift;; /* 1 */ \ -EX(.ex_handler, (p6) ld8 r22=[src1]); /* common, prime for tail section */ \ - nop.m 0; \ - (p16) shrp r38=r36,r37,shift; \ -EX(.ex_handler, (p17) st8 [dst0]=r35,8); /* 1 */ \ -EK(.ex_handler, (p17) st8 [dst1]=r39,8); \ - br.ctop.dptk.few 1b;; \ - (p7) add src1=-8,src1; /* back out for <8 byte case */ \ - shrp r21=r22,r38,shift; /* speculative work */ \ - br.sptk.few .unaligned_src_tail /* branch out of jump table */ \ - ;; - TEXT_ALIGN(32) -.jump_table: - COPYU(8) // unaligned cases -.jmp1: - COPYU(16) - COPYU(24) - COPYU(32) - COPYU(40) - COPYU(48) - COPYU(56) - -#undef A -#undef B -#undef C -#undef D - -/* - * Due to lack of local tag support in gcc 2.x assembler, it is not clear which - * instruction failed in the bundle. The exception algorithm is that we - * first figure out the faulting address, then detect if there is any - * progress made on the copy, if so, redo the copy from last known copied - * location up to the faulting address (exclusive). In the copy_from_user - * case, remaining byte in kernel buffer will be zeroed. - * - * Take copy_from_user as an example, in the code there are multiple loads - * in a bundle and those multiple loads could span over two pages, the - * faulting address is calculated as page_round_down(max(src0, src1)). - * This is based on knowledge that if we can access one byte in a page, we - * can access any byte in that page. - * - * predicate used in the exception handler: - * p6-p7: direction - * p10-p11: src faulting addr calculation - * p12-p13: dst faulting addr calculation - */ - -#define A r19 -#define B r20 -#define C r21 -#define D r22 -#define F r28 - -#define saved_retval loc0 -#define saved_rtlink loc1 -#define saved_pfs_stack loc2 - -.ex_hndlr_s: - add src0=8,src0 - br.sptk .ex_handler - ;; -.ex_hndlr_d: - add dst0=8,dst0 - br.sptk .ex_handler - ;; -.ex_hndlr_lcpy_1: - mov src1=src_pre_mem - mov dst1=dst_pre_mem - cmp.gtu p10,p11=src_pre_mem,saved_in1 - cmp.gtu p12,p13=dst_pre_mem,saved_in0 - ;; -(p10) add src0=8,saved_in1 -(p11) mov src0=saved_in1 -(p12) add dst0=8,saved_in0 -(p13) mov dst0=saved_in0 - br.sptk .ex_handler -.ex_handler_lcpy: - // in line_copy block, the preload addresses should always ahead - // of the other two src/dst pointers. Furthermore, src1/dst1 should - // always ahead of src0/dst0. - mov src1=src_pre_mem - mov dst1=dst_pre_mem -.ex_handler: - mov pr=saved_pr,-1 // first restore pr, lc, and pfs - mov ar.lc=saved_lc - mov ar.pfs=saved_pfs - ;; -.ex_handler_short: // fault occurred in these sections didn't change pr, lc, pfs - cmp.ltu p6,p7=saved_in0, saved_in1 // get the copy direction - cmp.ltu p10,p11=src0,src1 - cmp.ltu p12,p13=dst0,dst1 - fcmp.eq p8,p0=f6,f0 // is it memcpy? - mov tmp = dst0 - ;; -(p11) mov src1 = src0 // pick the larger of the two -(p13) mov dst0 = dst1 // make dst0 the smaller one -(p13) mov dst1 = tmp // and dst1 the larger one - ;; -(p6) dep F = r0,dst1,0,PAGE_SHIFT // usr dst round down to page boundary -(p7) dep F = r0,src1,0,PAGE_SHIFT // usr src round down to page boundary - ;; -(p6) cmp.le p14,p0=dst0,saved_in0 // no progress has been made on store -(p7) cmp.le p14,p0=src0,saved_in1 // no progress has been made on load - mov retval=saved_in2 -(p8) ld1 tmp=[src1] // force an oops for memcpy call -(p8) st1 [dst1]=r0 // force an oops for memcpy call -(p14) br.ret.sptk.many rp - -/* - * The remaining byte to copy is calculated as: - * - * A = (faulting_addr - orig_src) -> len to faulting ld address - * or - * (faulting_addr - orig_dst) -> len to faulting st address - * B = (cur_dst - orig_dst) -> len copied so far - * C = A - B -> len need to be copied - * D = orig_len - A -> len need to be left along - */ -(p6) sub A = F, saved_in0 -(p7) sub A = F, saved_in1 - clrrrb - ;; - alloc saved_pfs_stack=ar.pfs,3,3,3,0 - cmp.lt p8,p0=A,r0 - sub B = dst0, saved_in0 // how many byte copied so far - ;; -(p8) mov A = 0; // A shouldn't be negative, cap it - ;; - sub C = A, B - sub D = saved_in2, A - ;; - cmp.gt p8,p0=C,r0 // more than 1 byte? - mov r8=0 - mov saved_retval = D - mov saved_rtlink = b0 - - add out0=saved_in0, B - add out1=saved_in1, B - mov out2=C -(p8) br.call.sptk.few b0=__copy_user // recursive call - ;; - - add saved_retval=saved_retval,r8 // above might return non-zero value - ;; - - mov retval=saved_retval - mov ar.pfs=saved_pfs_stack - mov b0=saved_rtlink - br.ret.sptk.many rp - -/* end of McKinley specific optimization */ -END(__copy_user) -EXPORT_SYMBOL(__copy_user) |