// SPDX-License-Identifier: GPL-2.0-only/* * asynchronous raid6 recovery self test * Copyright (c) 2009, Intel Corporation. * * based on drivers/md/raid6test/test.c: * 	Copyright 2002-2007 H. Peter Anvin */#include <linux/async_tx.h>#include <linux/gfp.h>#include <linux/mm.h>#include <linux/random.h>#include <linux/module.h> #undef pr#define pr(fmt, args...) pr_info("raid6test: " fmt, ##args) #define NDISKS 64 /* Including P and Q */ static struct page *dataptrs[NDISKS];unsigned int dataoffs[NDISKS];static addr_conv_t addr_conv[NDISKS];static struct page *data[NDISKS+3];static struct page *spare;static struct page *recovi;static struct page *recovj; static void callback(void *param){	struct completion *cmp = param; 	complete(cmp);} static void makedata(int disks){	int i; 	for (i = 0; i < disks; i++) {		get_random_bytes(page_address(data[i]), PAGE_SIZE);		dataptrs[i] = data[i];		dataoffs[i] = 0;	}} static char disk_type(int d, int disks){	if (d == disks - 2)		return 'P';	else if (d == disks - 1)		return 'Q';	else		return 'D';} /* Recover two failed blocks. */static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb,		struct page **ptrs, unsigned int *offs){	struct async_submit_ctl submit;	struct completion cmp;	struct dma_async_tx_descriptor *tx = NULL;	enum sum_check_flags result = ~0; 	if (faila > failb)		swap(faila, failb); 	if (failb == disks-1) {		if (faila == disks-2) {			/* P+Q failure.  Just rebuild the syndrome. */			init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);			tx = async_gen_syndrome(ptrs, offs,					disks, bytes, &submit);		} else {			struct page *blocks[NDISKS];			struct page *dest;			int count = 0;			int i; 			BUG_ON(disks > NDISKS); 			/* data+Q failure.  Reconstruct data from P,			 * then rebuild syndrome			 */			for (i = disks; i-- ; ) {				if (i == faila || i == failb)					continue;				blocks[count++] = ptrs[i];			}			dest = ptrs[faila];			init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL,					  NULL, NULL, addr_conv);			tx = async_xor(dest, blocks, 0, count, bytes, &submit); 			init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv);			tx = async_gen_syndrome(ptrs, offs,					disks, bytes, &submit);		}	} else {		if (failb == disks-2) {			/* data+P failure. */			init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);			tx = async_raid6_datap_recov(disks, bytes,					faila, ptrs, offs, &submit);		} else {			/* data+data failure. */			init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);			tx = async_raid6_2data_recov(disks, bytes,					faila, failb, ptrs, offs, &submit);		}	}	init_completion(&cmp);	init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv);	tx = async_syndrome_val(ptrs, offs,			disks, bytes, &result, spare, 0, &submit);	async_tx_issue_pending(tx); 	if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0)		pr("%s: timeout! (faila: %d failb: %d disks: %d)\n",		   __func__, faila, failb, disks); 	if (result != 0)		pr("%s: validation failure! faila: %d failb: %d sum_check_flags: %x\n",		   __func__, faila, failb, result);} static int test_disks(int i, int j, int disks){	int erra, errb; 	memset(page_address(recovi), 0xf0, PAGE_SIZE);	memset(page_address(recovj), 0xba, PAGE_SIZE); 	dataptrs[i] = recovi;	dataptrs[j] = recovj; 	raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs, dataoffs); 	erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE);	errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE); 	pr("%s(%d, %d): faila=%3d(%c)  failb=%3d(%c)  %s\n",	   __func__, i, j, i, disk_type(i, disks), j, disk_type(j, disks),	   (!erra && !errb) ? "OK" : !erra ? "ERRB" : !errb ? "ERRA" : "ERRAB"); 	dataptrs[i] = data[i];	dataptrs[j] = data[j]; 	return erra || errb;} static int test(int disks, int *tests){	struct dma_async_tx_descriptor *tx;	struct async_submit_ctl submit;	struct completion cmp;	int err = 0;	int i, j; 	recovi = data[disks];	recovj = data[disks+1];	spare  = data[disks+2]; 	makedata(disks); 	/* Nuke syndromes */	memset(page_address(data[disks-2]), 0xee, PAGE_SIZE);	memset(page_address(data[disks-1]), 0xee, PAGE_SIZE); 	/* Generate assumed good syndrome */	init_completion(&cmp);	init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv);	tx = async_gen_syndrome(dataptrs, dataoffs, disks, PAGE_SIZE, &submit);	async_tx_issue_pending(tx); 	if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) {		pr("error: initial gen_syndrome(%d) timed out\n", disks);		return 1;	} 	pr("testing the %d-disk case...\n", disks);	for (i = 0; i < disks-1; i++)		for (j = i+1; j < disks; j++) {			(*tests)++;			err += test_disks(i, j, disks);		} 	return err;}  static int __init raid6_test(void){	int err = 0;	int tests = 0;	int i; 	for (i = 0; i < NDISKS+3; i++) {		data[i] = alloc_page(GFP_KERNEL);		if (!data[i]) {			while (i--)				put_page(data[i]);			return -ENOMEM;		}	} 	/* the 4-disk and 5-disk cases are special for the recovery code */	if (NDISKS > 4)		err += test(4, &tests);	if (NDISKS > 5)		err += test(5, &tests);	/* the 11 and 12 disk cases are special for ioatdma (p-disabled	 * q-continuation without extended descriptor)	 */	if (NDISKS > 12) {		err += test(11, &tests);		err += test(12, &tests);	} 	/* the 24 disk case is special for ioatdma as it is the boundary point	 * at which it needs to switch from 8-source ops to 16-source	 * ops for continuation (assumes DMA_HAS_PQ_CONTINUE is not set)	 */	if (NDISKS > 24)		err += test(24, &tests); 	err += test(NDISKS, &tests); 	pr("\n");	pr("complete (%d tests, %d failure%s)\n",	   tests, err, err == 1 ? "" : "s"); 	for (i = 0; i < NDISKS+3; i++)		put_page(data[i]); 	return 0;} static void __exit raid6_test_exit(void){} /* when compiled-in wait for drivers to load first (assumes dma drivers * are also compiled-in) */late_initcall(raid6_test);module_exit(raid6_test_exit);MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>");MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests");MODULE_LICENSE("GPL");