// Copyright (c) Vitaliy Filippov, 2019+
// License: VNPL-1.1 (see README.md for details)

#define RMW_DEBUG

#ifdef NO_ISAL
#undef WITH_ISAL
#endif

#include <string.h>
#include "osd_rmw.cpp"
#include "test_pattern.h"

void dump_stripes(osd_rmw_stripe_t *stripes, int pg_size);
void test1();
void test4();
void test5();
void test6();
void test7();
void test_rmw_4k_degraded_into_lost_to_normal(bool ec);
void test8();
void test9();
void test10();
void test11();
void test12();
void test13();
void test14();
void test15(bool second);
void test16();
void test_recover_22_d2();
void test_ec43_error_bruteforce();
void test_recover_53_d5();
void test_recover_22();

int main(int narg, char *args[])
{
    // Test 1
    test1();
    // Test 4
    test4();
    // Test 5
    test5();
    // Test 6
    test6();
    // Test 7
    test7();
    test_rmw_4k_degraded_into_lost_to_normal(false);
    test_rmw_4k_degraded_into_lost_to_normal(true);
    // Test 8
    test8();
    // Test 9
    test9();
    // Test 10
    test10();
    // Test 11
    test11();
    // Test 12
    test12();
    // Test 13
    test13();
    // Test 14
    test14();
    // Test 15
    test15(false);
    test15(true);
    // Test 16
    test16();
    // Test 17
    test_recover_22_d2();
    // Error bruteforce
    test_ec43_error_bruteforce();
    // Test 19
    test_recover_53_d5();
    // Test 20
    test_recover_22();
    // End
    printf("all ok\n");
    return 0;
}

void dump_stripes(osd_rmw_stripe_t *stripes, int pg_size)
{
    printf("request");
    for (int i = 0; i < pg_size; i++)
    {
        printf(" {%uK-%uK}", stripes[i].req_start/1024, stripes[i].req_end/1024);
    }
    printf("\n");
    printf("read");
    for (int i = 0; i < pg_size; i++)
    {
        printf(" {%uK-%uK}", stripes[i].read_start/1024, stripes[i].read_end/1024);
    }
    printf("\n");
    printf("write");
    for (int i = 0; i < pg_size; i++)
    {
        printf(" {%uK-%uK}", stripes[i].write_start/1024, stripes[i].write_end/1024);
    }
    printf("\n");
}

/***

1. split(offset=128K-4K, len=8K)
   = [ [ 128K-4K, 128K ], [ 0, 4K ], [ 0, 0 ] ]

   read(offset=128K-4K, len=8K, osd_set=[1,0,3])
   = { read: [ [ 0, 128K ], [ 0, 4K ], [ 0, 4K ] ] }

   cover_read(0, 128K, { req: [ 128K-4K, 4K ] })
   = { read: [ 0, 128K-4K ] }

***/

void test1()
{
    osd_num_t osd_set[3] = { 1, 0, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 1.1
    split_stripes(2, 128*1024, 128*1024-4096, 8192, stripes);
    assert(stripes[0].req_start == 128*1024-4096 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 4096);
    assert(stripes[2].req_end == 0);
    // Test 1.2
    for (int i = 0; i < 3; i++)
    {
        stripes[i].read_start = stripes[i].req_start;
        stripes[i].read_end = stripes[i].req_end;
    }
    assert(extend_missing_stripes(stripes, osd_set, 2, 3) == 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 4096);
    // Test 1.3
    stripes[0] = (osd_rmw_stripe_t){ .req_start = 128*1024-4096, .req_end = 128*1024 };
    cover_read(0, 128*1024, stripes[0]);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024-4096);
}

/***

4. write(offset=128K-4K, len=8K, osd_set=[1,0,3])
   = {
     read: [ [ 0, 128K ], [ 4K, 128K ], [ 4K, 128K ] ],
     write: [ [ 128K-4K, 128K ], [ 0, 4K ], [ 0, 128K ] ],
     input buffer: [ write0, write1 ],
     rmw buffer: [ write2, read0, read1, read2 ],
   }
   + check write2 buffer

***/

void test4()
{
    const uint32_t bmp = 4;
    unsigned bitmaps[3] = { 0 };
    osd_num_t osd_set[3] = { 1, 0, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 4.1
    split_stripes(2, 128*1024, 128*1024-4096, 8192, stripes);
    for (int i = 0; i < 3; i++)
        stripes[i].bmp_buf = bitmaps+i;
    void* write_buf = malloc(8192);
    void* rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 2, osd_set, 128*1024, bmp);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 4096 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 4096 && stripes[2].read_end == 128*1024);
    assert(stripes[0].write_start == 128*1024-4096 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 4096);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+128*1024*2);
    assert(stripes[2].read_buf == (uint8_t*)rmw_buf+128*1024*3-4096);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+4096);
    assert(stripes[2].write_buf == rmw_buf);
    // Test 4.2
    set_pattern(write_buf, 8192, PATTERN0);
    set_pattern(stripes[0].read_buf, 128*1024, PATTERN1); // old data
    set_pattern(stripes[1].read_buf, 128*1024-4096, UINT64_MAX); // didn't read it, it's missing
    set_pattern(stripes[2].read_buf, 128*1024-4096, 0); // old parity = 0
    memset(stripes[0].bmp_buf, 0, bmp);
    memset(stripes[1].bmp_buf, 0, bmp);
    memset(stripes[2].bmp_buf, 0, bmp);
    calc_rmw_parity_xor(stripes, 3, osd_set, osd_set, 128*1024, bmp);
    assert(*(uint32_t*)stripes[0].bmp_buf == 0x80000000);
    assert(*(uint32_t*)stripes[1].bmp_buf == 0x00000001);
    assert(*(uint32_t*)stripes[2].bmp_buf == 0x80000001); // XOR
    check_pattern(stripes[2].write_buf, 4096, PATTERN0^PATTERN1); // new parity
    check_pattern(stripes[2].write_buf+4096, 128*1024-4096*2, 0); // new parity
    check_pattern(stripes[2].write_buf+128*1024-4096, 4096, PATTERN0^PATTERN1); // new parity
    free(rmw_buf);
    free(write_buf);
}

/***

5. write(offset=0, len=128K+64K, osd_set=[1,0,3])
   = {
     req: [ [ 0, 128K ], [ 0, 64K ], [ 0, 0 ] ],
     read: [ [ 64K, 128K ], [ 64K, 128K ], [ 64K, 128K ] ],
     write: [ [ 0, 128K ], [ 0, 64K ], [ 0, 128K ] ],
     input buffer: [ write0, write1 ],
     rmw buffer: [ write2, read0, read1, read2 ],
   }

***/

void test5()
{
    osd_num_t osd_set[3] = { 1, 0, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 5.1
    split_stripes(2, 128*1024, 0, 64*1024*3, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 64*1024);
    assert(stripes[2].req_end == 0);
    // Test 5.2
    void *write_buf = malloc(64*1024*3);
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 2, osd_set, 128*1024, 0);
    assert(stripes[0].read_start == 64*1024 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 64*1024 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 64*1024 && stripes[2].read_end == 128*1024);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 64*1024);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+64*3*1024);
    assert(stripes[2].read_buf == (uint8_t*)rmw_buf+64*4*1024);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+128*1024);
    assert(stripes[2].write_buf == rmw_buf);
    free(rmw_buf);
    free(write_buf);
}

/***

6. write(offset=0, len=128K+64K, osd_set=[1,2,3])
   = {
     req: [ [ 0, 128K ], [ 0, 64K ], [ 0, 0 ] ],
     read: [ [ 0, 0 ], [ 64K, 128K ], [ 0, 0 ] ],
     write: [ [ 0, 128K ], [ 0, 64K ], [ 0, 128K ] ],
     input buffer: [ write0, write1 ],
     rmw buffer: [ write2, read1 ],
   }

***/

void test6()
{
    osd_num_t osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 6.1
    split_stripes(2, 128*1024, 0, 64*1024*3, stripes);
    void *write_buf = malloc(64*1024*3);
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 3, osd_set, 128*1024, 0);
    assert(stripes[0].read_end == 0);
    assert(stripes[1].read_start == 64*1024 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_end == 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 64*1024);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == 0);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[2].read_buf == 0);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+128*1024);
    assert(stripes[2].write_buf == rmw_buf);
    free(rmw_buf);
    free(write_buf);
}

/***

7. calc_rmw(offset=128K-4K, len=8K, osd_set=[1,0,3], write_set=[1,2,3])
   = {
     read: [ [ 0, 128K ], [ 0, 128K ], [ 0, 128K ] ],
     write: [ [ 128K-4K, 128K ], [ 0, 4K ], [ 0, 128K ] ],
     input buffer: [ write0, write1 ],
     rmw buffer: [ write2, read0, read1, read2 ],
   }
   then, after calc_rmw_parity_xor(): {
     write: [ [ 128K-4K, 128K ], [ 0, 128K ], [ 0, 128K ] ],
     write1==read1,
   }
   + check write1 buffer
   + check write2 buffer

***/

void test7()
{
    osd_num_t osd_set[3] = { 1, 0, 3 };
    osd_num_t write_osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 7.1
    split_stripes(2, 128*1024, 128*1024-4096, 8192, stripes);
    void *write_buf = malloc(8192);
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 2, write_osd_set, 128*1024, 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    assert(stripes[0].write_start == 128*1024-4096 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 4096);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+128*1024*2);
    assert(stripes[2].read_buf == (uint8_t*)rmw_buf+128*1024*3);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+4096);
    assert(stripes[2].write_buf == rmw_buf);
    // Test 7.2
    set_pattern(write_buf, 8192, PATTERN0);
    set_pattern(stripes[0].read_buf, 128*1024, PATTERN1); // old data
    set_pattern(stripes[1].read_buf, 128*1024, UINT64_MAX); // didn't read it, it's missing
    set_pattern(stripes[2].read_buf, 128*1024, 0); // old parity = 0
    calc_rmw_parity_xor(stripes, 3, osd_set, write_osd_set, 128*1024, 0);
    assert(stripes[0].write_start == 128*1024-4096 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 128*1024);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[1].write_buf == stripes[1].read_buf);
    check_pattern(stripes[1].write_buf, 4096, PATTERN0);
    check_pattern(stripes[1].write_buf+4096, 128*1024-4096, PATTERN1);
    check_pattern(stripes[2].write_buf, 4096, PATTERN0^PATTERN1); // new parity
    check_pattern(stripes[2].write_buf+4096, 128*1024-4096*2, 0); // new parity
    check_pattern(stripes[2].write_buf+128*1024-4096, 4096, PATTERN0^PATTERN1); // new parity
    free(rmw_buf);
    free(write_buf);
}

/***

7/2. calc_rmw(offset=48K, len=4K, osd_set=[0,2,3], write_set=[1,2,3])
   = {
     read: [ [ 0, 128K ], [ 0, 128K ], [ 0, 128K ] ],
     write: [ [ 48K, 52K ], [ 0, 0 ], [ 48K, 52K ] ],
     input buffer: [ write0 ],
     rmw buffer: [ write2, read0, read1, read2 ],
   }
   then, after calc_rmw_parity_xor/ec(): {
     write: [ [ 0, 128K ], [ 0, 0 ], [ 48K, 52K ] ],
     write0==read0,
   }
   + check write0, write2 buffers

***/

void test_rmw_4k_degraded_into_lost_to_normal(bool ec)
{
    osd_num_t osd_set[3] = { 0, 2, 3 };
    osd_num_t write_osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Subtest 1
    split_stripes(2, 128*1024, 48*1024, 4096, stripes);
    void *write_buf = malloc(4096);
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 3, write_osd_set, 128*1024, 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    assert(stripes[0].write_start == 48*1024 && stripes[0].write_end == 52*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 48*1024 && stripes[2].write_end == 52*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+4*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+4*1024+128*1024);
    assert(stripes[2].read_buf == (uint8_t*)rmw_buf+4*1024+2*128*1024);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == rmw_buf);
    // Subtest 2
    set_pattern(write_buf, 4096, PATTERN2);
    set_pattern(stripes[1].read_buf, 128*1024, PATTERN1);
    set_pattern(stripes[2].read_buf, 128*1024, PATTERN0^PATTERN1);
    if (!ec)
        calc_rmw_parity_xor(stripes, 3, osd_set, write_osd_set, 128*1024, 0);
    else
    {
        use_ec(3, 2, true);
        calc_rmw_parity_ec(stripes, 3, 2, osd_set, write_osd_set, 128*1024, 0);
        use_ec(3, 2, false);
    }
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 48*1024 && stripes[2].write_end == 52*1024);
    assert(stripes[0].write_buf == stripes[0].read_buf);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == rmw_buf);
    check_pattern(stripes[0].write_buf, 4096, PATTERN0);
    check_pattern(stripes[0].write_buf+48*1024, 4096, PATTERN2);
    check_pattern(stripes[2].write_buf, 4096, PATTERN2^PATTERN1); // new parity
    free(rmw_buf);
    free(write_buf);
}

/***

8. calc_rmw(offset=0, len=128K+4K, osd_set=[0,2,3], write_set=[1,2,3])
   = {
     read: [ [ 0, 0 ], [ 4K, 128K ], [ 0, 0 ] ],
     write: [ [ 0, 128K ], [ 0, 4K ], [ 0, 128K ] ],
     input buffer: [ write0, write1 ],
     rmw buffer: [ write2, read1 ],
   }
   + check write2 buffer

***/

void test8()
{
    osd_num_t osd_set[3] = { 0, 2, 3 };
    osd_num_t write_osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 8.1
    split_stripes(2, 128*1024, 0, 128*1024+4096, stripes);
    void *write_buf = malloc(128*1024+4096);
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 2, write_osd_set, 128*1024, 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 0);
    assert(stripes[1].read_start == 4096 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 4096);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == NULL);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+128*1024);
    assert(stripes[2].write_buf == rmw_buf);
    // Test 8.2
    set_pattern(write_buf, 128*1024+4096, PATTERN0);
    set_pattern(stripes[1].read_buf, 128*1024-4096, PATTERN1);
    calc_rmw_parity_xor(stripes, 3, osd_set, write_osd_set, 128*1024, 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024); // recheck again
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 4096);     // recheck again
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024); // recheck again
    assert(stripes[0].write_buf == write_buf);                               // recheck again
    assert(stripes[1].write_buf == (uint8_t*)write_buf+128*1024);                      // recheck again
    assert(stripes[2].write_buf == rmw_buf);                                 // recheck again
    check_pattern(stripes[2].write_buf, 4096, 0); // new parity
    check_pattern(stripes[2].write_buf+4096, 128*1024-4096, PATTERN0^PATTERN1); // new parity
    free(rmw_buf);
    free(write_buf);
}

/***

9. object recovery case:
   calc_rmw(offset=0, len=0, read_osd_set=[0,2,3], write_osd_set=[1,2,3])
   = {
     read: [ [ 0, 128K ], [ 0, 128K ], [ 0, 128K ] ],
     write: [ [ 0, 0 ], [ 0, 0 ], [ 0, 0 ] ],
     input buffer: NULL,
     rmw buffer: [ read0, read1, read2 ],
   }
   then, after calc_rmw_parity_xor(): {
     write: [ [ 0, 128K ], [ 0, 0 ], [ 0, 0 ] ],
     write0==read0,
   }
   + check write0 buffer

***/

void test9()
{
    osd_num_t osd_set[3] = { 0, 2, 3 };
    osd_num_t write_osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 9.0
    split_stripes(2, 128*1024, 64*1024, 0, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 0);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 0);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    // Test 9.1
    void *write_buf = NULL;
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 3, write_osd_set, 128*1024, 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 0);
    assert(stripes[0].read_buf == rmw_buf);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[2].read_buf == (uint8_t*)rmw_buf+128*1024*2);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == NULL);
    // Test 9.2
    set_pattern(stripes[1].read_buf, 128*1024, 0);
    set_pattern(stripes[2].read_buf, 128*1024, PATTERN1);
    calc_rmw_parity_xor(stripes, 3, osd_set, write_osd_set, 128*1024, 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 0);
    assert(stripes[0].write_buf == rmw_buf);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == NULL);
    check_pattern(stripes[0].read_buf, 128*1024, PATTERN1);
    check_pattern(stripes[0].write_buf, 128*1024, PATTERN1);
    free(rmw_buf);
}

/***

10. full overwrite/recovery case:
   calc_rmw(offset=0, len=256K, read_osd_set=[1,0,0], write_osd_set=[1,2,3])
   = {
     read: [ [ 0, 0 ], [ 0, 0 ], [ 0, 0 ] ],
     write: [ [ 0, 128K ], [ 0, 128K ], [ 0, 128K ] ],
     input buffer: [ write0, write1 ],
     rmw buffer: [ write2 ],
   }
   then, after calc_rmw_parity_xor(): all the same
   + check write2 buffer

***/

void test10()
{
    osd_num_t osd_set[3] = { 1, 0, 0 };
    osd_num_t write_osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 10.0
    split_stripes(2, 128*1024, 0, 256*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 128*1024);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    // Test 10.1
    void *write_buf = malloc(256*1024);
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 3, write_osd_set, 128*1024, 0);
    assert(rmw_buf);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 0);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 0);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 128*1024);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == NULL);
    assert(stripes[1].read_buf == NULL);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+128*1024);
    assert(stripes[2].write_buf == rmw_buf);
    // Test 10.2
    set_pattern(stripes[0].write_buf, 128*1024, PATTERN1);
    set_pattern(stripes[1].write_buf, 128*1024, PATTERN2);
    calc_rmw_parity_xor(stripes, 3, osd_set, write_osd_set, 128*1024, 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 128*1024);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+128*1024);
    assert(stripes[2].write_buf == rmw_buf);
    check_pattern(stripes[2].write_buf, 128*1024, PATTERN1^PATTERN2);
    free(rmw_buf);
    free(write_buf);
}

/***

11. partial recovery case:
   calc_rmw(offset=128K, len=128K, read_osd_set=[1,0,0], write_osd_set=[1,2,3])
   = {
     read: [ [ 0, 128K ], [ 0, 0 ], [ 0, 0 ] ],
     write: [ [ 0, 0 ], [ 0, 128K ], [ 0, 128K ] ],
     input buffer: [ write1 ],
     rmw buffer: [ write2, read0 ],
   }
   then, after calc_rmw_parity_xor(): all the same
   + check write2 buffer

***/

void test11()
{
    osd_num_t osd_set[3] = { 1, 0, 0 };
    osd_num_t write_osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 11.0
    split_stripes(2, 128*1024, 128*1024, 256*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 0);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 128*1024);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    // Test 11.1
    void *write_buf = malloc(256*1024);
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 3, write_osd_set, 128*1024, 0);
    assert(rmw_buf);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 0);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 128*1024);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[1].read_buf == NULL);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == write_buf);
    assert(stripes[2].write_buf == rmw_buf);
    // Test 11.2
    set_pattern(stripes[0].read_buf, 128*1024, PATTERN1);
    set_pattern(stripes[1].write_buf, 128*1024, PATTERN2);
    calc_rmw_parity_xor(stripes, 3, osd_set, write_osd_set, 128*1024, 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 128*1024);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == write_buf);
    assert(stripes[2].write_buf == rmw_buf);
    check_pattern(stripes[2].write_buf, 128*1024, PATTERN1^PATTERN2);
    free(rmw_buf);
    free(write_buf);
}

/***

12. parity recovery case:
   calc_rmw(offset=0, len=0, read_osd_set=[1,2,0], write_osd_set=[1,2,3])
   = {
     read: [ [ 0, 128K ], [ 0, 128K ], [ 0, 0 ] ],
     write: [ [ 0, 0 ], [ 0, 0 ], [ 0, 128K ] ],
     input buffer: [],
     rmw buffer: [ write2, read0, read1 ],
   }
   then, after calc_rmw_parity_xor(): all the same
   + check write2 buffer

***/

void test12()
{
    osd_num_t osd_set[3] = { 1, 2, 0 };
    osd_num_t write_osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    // Test 12.0
    split_stripes(2, 128*1024, 0, 0, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 0);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 0);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    // Test 12.1
    void *rmw_buf = calc_rmw(NULL, stripes, osd_set, 3, 2, 3, write_osd_set, 128*1024, 0);
    assert(rmw_buf);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+2*128*1024);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == rmw_buf);
    // Test 12.2
    set_pattern(stripes[0].read_buf, 128*1024, PATTERN1);
    set_pattern(stripes[1].read_buf, 128*1024, PATTERN2);
    calc_rmw_parity_xor(stripes, 3, osd_set, write_osd_set, 128*1024, 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == rmw_buf);
    check_pattern(stripes[2].write_buf, 128*1024, PATTERN1^PATTERN2);
    free(rmw_buf);
}

/***

13. basic jerasure 2+2 test
   calc_rmw(offset=128K-4K, len=8K, osd_set=[1,2,0,0], write_set=[1,2,3,4])
   = {
     read: [ [ 0, 128K ], [ 0, 128K ], [ 0, 0 ], [ 0, 0 ] ],
     write: [ [ 128K-4K, 128K ], [ 0, 4K ], [ 0, 128K ], [ 0, 128K ] ],
     input buffer: [ write0, write1 ],
     rmw buffer: [ write2, write3, read0, read1 ],
   }
   then, after calc_rmw_parity_ec(): all the same
   then simulate read with read_osd_set=[0,0,3,4] and check read0,read1 buffers

***/

void test13()
{
    use_ec(4, 2, true);
    osd_num_t osd_set[4] = { 1, 2, 0, 0 };
    osd_num_t write_osd_set[4] = { 1, 2, 3, 4 };
    osd_rmw_stripe_t stripes[4] = {};
    // Test 13.0
    void *write_buf = malloc_or_die(8192);
    split_stripes(2, 128*1024, 128*1024-4096, 8192, stripes);
    assert(stripes[0].req_start == 128*1024-4096 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 4096);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    // Test 13.1
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 4, 2, 4, write_osd_set, 128*1024, 0);
    assert(rmw_buf);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024-4096);
    assert(stripes[1].read_start == 4096 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 0);
    assert(stripes[0].write_start == 128*1024-4096 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 4096);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[3].write_start == 0 && stripes[3].write_end == 128*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+2*128*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+3*128*1024-4096);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[3].read_buf == NULL);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+4096);
    assert(stripes[2].write_buf == rmw_buf);
    assert(stripes[3].write_buf == (uint8_t*)rmw_buf+128*1024);
    // Test 13.2 - encode
    set_pattern(write_buf, 8192, PATTERN3);
    set_pattern(stripes[0].read_buf, 128*1024-4096, PATTERN1);
    set_pattern(stripes[1].read_buf, 128*1024-4096, PATTERN2);
    calc_rmw_parity_ec(stripes, 4, 2, osd_set, write_osd_set, 128*1024, 0);
    assert(stripes[0].write_start == 128*1024-4096 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 4096);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[3].write_start == 0 && stripes[3].write_end == 128*1024);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+4096);
    assert(stripes[2].write_buf == rmw_buf);
    assert(stripes[3].write_buf == (uint8_t*)rmw_buf+128*1024);
    // Test 13.3 - full decode and verify
    osd_num_t read_osd_set[4] = { 0, 0, 3, 4 };
    memset(stripes, 0, sizeof(stripes));
    split_stripes(2, 128*1024, 0, 256*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 128*1024);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    for (int role = 0; role < 4; role++)
    {
        stripes[role].read_start = stripes[role].req_start;
        stripes[role].read_end = stripes[role].req_end;
    }
    assert(extend_missing_stripes(stripes, read_osd_set, 2, 4) == 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 128*1024);
    void *read_buf = alloc_read_buffer(stripes, 4, 0);
    assert(read_buf);
    assert(stripes[0].read_buf == read_buf);
    assert(stripes[1].read_buf == (uint8_t*)read_buf+128*1024);
    assert(stripes[2].read_buf == (uint8_t*)read_buf+2*128*1024);
    assert(stripes[3].read_buf == (uint8_t*)read_buf+3*128*1024);
    memcpy((uint8_t*)read_buf+2*128*1024, rmw_buf, 128*1024);
    memcpy((uint8_t*)read_buf+3*128*1024, (uint8_t*)rmw_buf+128*1024, 128*1024);
    reconstruct_stripes_ec(stripes, 4, 2, 0);
    check_pattern(stripes[0].read_buf, 128*1024-4096, PATTERN1);
    check_pattern(stripes[0].read_buf+128*1024-4096, 4096, PATTERN3);
    check_pattern(stripes[1].read_buf, 4096, PATTERN3);
    check_pattern(stripes[1].read_buf+4096, 128*1024-4096, PATTERN2);
    free(read_buf);
    // Test 13.4 - partial decode (only 1st chunk) and verify
    memset(stripes, 0, sizeof(stripes));
    split_stripes(2, 128*1024, 0, 128*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 0);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    for (int role = 0; role < 4; role++)
    {
        stripes[role].read_start = stripes[role].req_start;
        stripes[role].read_end = stripes[role].req_end;
    }
    assert(extend_missing_stripes(stripes, read_osd_set, 2, 4) == 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 0);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 128*1024);
    read_buf = alloc_read_buffer(stripes, 4, 0);
    assert(read_buf);
    assert(stripes[0].read_buf == read_buf);
    assert(stripes[1].read_buf == NULL);
    assert(stripes[2].read_buf == (uint8_t*)read_buf+128*1024);
    assert(stripes[3].read_buf == (uint8_t*)read_buf+2*128*1024);
    memcpy((uint8_t*)read_buf+128*1024, rmw_buf, 128*1024);
    memcpy((uint8_t*)read_buf+2*128*1024, (uint8_t*)rmw_buf+128*1024, 128*1024);
    reconstruct_stripes_ec(stripes, 4, 2, 0);
    check_pattern(stripes[0].read_buf, 128*1024-4096, PATTERN1);
    check_pattern(stripes[0].read_buf+128*1024-4096, 4096, PATTERN3);
    free(read_buf);
    // Huh done
    free(rmw_buf);
    free(write_buf);
    use_ec(4, 2, false);
}

/***

14. basic jerasure 2+1 test
   calc_rmw(offset=128K-4K, len=8K, osd_set=[1,2,0], write_set=[1,2,3])
   = {
     read: [ [ 0, 128K ], [ 0, 128K ], [ 0, 0 ] ],
     write: [ [ 128K-4K, 128K ], [ 0, 4K ], [ 0, 128K ] ],
     input buffer: [ write0, write1 ],
     rmw buffer: [ write2, read0, read1 ],
   }
   then, after calc_rmw_parity_ec(): all the same
   then simulate read with read_osd_set=[0,2,3] and check read0 buffer

***/

void test14()
{
    const int bmp = 4;
    use_ec(3, 2, true);
    osd_num_t osd_set[3] = { 1, 2, 0 };
    osd_num_t write_osd_set[3] = { 1, 2, 3 };
    osd_rmw_stripe_t stripes[3] = {};
    unsigned bitmaps[3] = { 0 };
    // Test 14.0
    void *write_buf = malloc_or_die(8192);
    split_stripes(2, 128*1024, 128*1024-4096, 8192, stripes);
    assert(stripes[0].req_start == 128*1024-4096 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 4096);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    // Test 14.1
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 3, 2, 3, write_osd_set, 128*1024, bmp);
    for (int i = 0; i < 3; i++)
        stripes[i].bmp_buf = bitmaps+i;
    assert(rmw_buf);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024-4096);
    assert(stripes[1].read_start == 4096 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[0].write_start == 128*1024-4096 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 4096);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+2*128*1024-4096);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+4096);
    assert(stripes[2].write_buf == rmw_buf);
    // Test 14.2 - encode
    set_pattern(write_buf, 8192, PATTERN3);
    set_pattern(stripes[0].read_buf, 128*1024-4096, PATTERN1);
    set_pattern(stripes[1].read_buf, 128*1024-4096, PATTERN2);
    memset(stripes[0].bmp_buf, 0, bmp);
    memset(stripes[1].bmp_buf, 0, bmp);
    memset(stripes[2].bmp_buf, 0, bmp);
    calc_rmw_parity_ec(stripes, 3, 2, osd_set, write_osd_set, 128*1024, bmp);
    assert(*(uint32_t*)stripes[0].bmp_buf == 0x80000000);
    assert(*(uint32_t*)stripes[1].bmp_buf == 0x00000001);
    assert(*(uint32_t*)stripes[2].bmp_buf == 0x80000001); // jerasure 2+1 is still just XOR
    assert(stripes[0].write_start == 128*1024-4096 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 4096);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 128*1024);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == (uint8_t*)write_buf+4096);
    assert(stripes[2].write_buf == rmw_buf);
    // Test 14.3 - decode and verify
    osd_num_t read_osd_set[4] = { 0, 2, 3 };
    memset(stripes, 0, sizeof(stripes));
    split_stripes(2, 128*1024, 0, 128*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 0);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    for (int role = 0; role < 3; role++)
    {
        stripes[role].read_start = stripes[role].req_start;
        stripes[role].read_end = stripes[role].req_end;
    }
    assert(extend_missing_stripes(stripes, read_osd_set, 2, 3) == 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    void *read_buf = alloc_read_buffer(stripes, 3, 0);
    for (int i = 0; i < 3; i++)
        stripes[i].bmp_buf = bitmaps+i;
    assert(read_buf);
    assert(stripes[0].read_buf == read_buf);
    assert(stripes[1].read_buf == (uint8_t*)read_buf+128*1024);
    assert(stripes[2].read_buf == (uint8_t*)read_buf+2*128*1024);
    set_pattern(stripes[1].read_buf, 4096, PATTERN3);
    set_pattern(stripes[1].read_buf+4096, 128*1024-4096, PATTERN2);
    memcpy(stripes[2].read_buf, rmw_buf, 128*1024);
    reconstruct_stripes_ec(stripes, 3, 2, bmp);
    check_pattern(stripes[0].read_buf, 128*1024-4096, PATTERN1);
    check_pattern(stripes[0].read_buf+128*1024-4096, 4096, PATTERN3);
    free(read_buf);
    // Huh done
    free(rmw_buf);
    free(write_buf);
    use_ec(3, 2, false);
}

/***

15. EC 2+2 partial overwrite with 1 missing stripe
   calc_rmw(offset=64K+28K, len=4K, osd_set=[1,2,3,0], write_set=[1,2,3,0])
   = {
     read: [ [ 28K, 32K ], [ 0, 0 ], [ 0, 0 ], [ 0, 0 ] ],
     write: [ [ 0, 0 ], [ 28K, 32K ], [ 28K, 32K ], [ 0, 0 ] ],
     input buffer: [ write1 ],
     rmw buffer: [ write2, read0 ],
   }

***/

void test15(bool second)
{
    const int bmp = 64*1024 / 4096 / 8;
    use_ec(4, 2, true);
    osd_num_t osd_set[4] = { 1, 2, (osd_num_t)(second ? 0 : 3), (osd_num_t)(second ? 4 : 0) };
    osd_rmw_stripe_t stripes[4] = {};
    unsigned bitmaps[4] = { 0 };
    // Test 15.0
    void *write_buf = malloc_or_die(4096);
    split_stripes(2, 64*1024, (64+28)*1024, 4096, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 0);
    assert(stripes[1].req_start == 28*1024 && stripes[1].req_end == 32*1024);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    // Test 15.1
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 4, 2, 3, osd_set, 64*1024, bmp);
    for (int i = 0; i < 4; i++)
        stripes[i].bmp_buf = bitmaps+i;
    assert(rmw_buf);
    assert(stripes[0].read_start == 28*1024 && stripes[0].read_end == 32*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 0);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 28*1024 && stripes[1].write_end == 32*1024);
    assert(stripes[2+second].write_start == 28*1024 && stripes[2+second].write_end == 32*1024);
    assert(stripes[3-second].write_start == 0 && stripes[3-second].write_end == 0);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+4*1024);
    assert(stripes[1].read_buf == NULL);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[3].read_buf == NULL);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == (uint8_t*)write_buf);
    assert(stripes[2+second].write_buf == rmw_buf);
    assert(stripes[3-second].write_buf == NULL);
    // Test 15.2 - encode
    set_pattern(write_buf, 4*1024, PATTERN1);
    set_pattern(stripes[0].read_buf, 4*1024, PATTERN2);
    memset(stripes[0].bmp_buf, 0, bmp);
    memset(stripes[1].bmp_buf, 0, bmp);
    memset(stripes[2+second].write_buf, 0, 4096);
    calc_rmw_parity_ec(stripes, 4, 2, osd_set, osd_set, 64*1024, bmp);
    assert(second || *(uint32_t*)stripes[2].bmp_buf == 0x80);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 28*1024 && stripes[1].write_end == 32*1024);
    assert(stripes[2+second].write_start == 28*1024 && stripes[2+second].write_end == 32*1024);
    assert(stripes[3-second].write_start == 0 && stripes[3-second].write_end == 0);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == (uint8_t*)write_buf);
    assert(stripes[2+second].write_buf == rmw_buf);
    assert(stripes[3-second].write_buf == NULL);
    // first parity is always xor :), second isn't...
    check_pattern(stripes[2+second].write_buf, 4*1024, second ? 0xb79a59a0ce8b9b81 : PATTERN1^PATTERN2);
    // Done
    free(rmw_buf);
    free(write_buf);
    use_ec(4, 2, false);
}

/***

16. EC 2+2 write one parity block with another missing
   calc_rmw(offset=0, len=0, osd_set=[1,2,0,0], write_set=[1,2,0,3])
   = {
     read: [ [ 0, 128K ], [ 0, 128K ], [ 0, 0 ], [ 0, 0 ] ],
     write: [ [ 0, 0 ], [ 0, 0 ], [ 0, 0 ], [ 0, 128K ] ],
     input buffer: [],
     rmw buffer: [ write3, read0, read1 ],
   }

***/

void test16()
{
    const int bmp = 128*1024 / 4096 / 8;
    use_ec(4, 2, true);
    osd_num_t osd_set[4] = { 1, 2, 0, 0 };
    osd_num_t write_osd_set[4] = { 1, 2, 0, 3 };
    osd_rmw_stripe_t stripes[4] = {};
    unsigned bitmaps[4] = { 0 };
    // Test 16.0
    void *write_buf = NULL;
    split_stripes(2, 128*1024, 0, 0, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 0);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 0);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    // Test 16.1
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 4, 2, 3, write_osd_set, 128*1024, bmp);
    for (int i = 0; i < 4; i++)
        stripes[i].bmp_buf = bitmaps+i;
    assert(rmw_buf);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 0);
    assert(stripes[3].write_start == 0 && stripes[3].write_end == 128*1024);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+128*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+256*1024);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[3].read_buf == NULL);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == NULL);
    assert(stripes[3].write_buf == rmw_buf);
    // Test 16.2 - encode
    set_pattern(stripes[0].read_buf, 128*1024, PATTERN1);
    set_pattern(stripes[1].read_buf, 128*1024, PATTERN2);
    memset(stripes[0].bmp_buf, 0xff, bmp);
    memset(stripes[1].bmp_buf, 0xff, bmp);
    calc_rmw_parity_ec(stripes, 4, 2, osd_set, write_osd_set, 128*1024, bmp);
    assert(*(uint32_t*)stripes[2].bmp_buf == 0);
    assert(*(uint32_t*)stripes[3].bmp_buf == 0xF1F1F1F1);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 0 && stripes[2].write_end == 0);
    assert(stripes[3].write_start == 0 && stripes[3].write_end == 128*1024);
    assert(stripes[0].write_buf == NULL);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == NULL);
    assert(stripes[3].write_buf == rmw_buf);
    check_pattern(stripes[3].write_buf, 128*1024, 0x7eb9ae9cd8e652c3); // 2nd EC chunk
    // Test 16.3 - decode and verify
    osd_num_t read_osd_set[4] = { 0, 2, 0, 3 };
    memset(stripes, 0, sizeof(stripes));
    split_stripes(2, 128*1024, 0, 256*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 128*1024);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    for (int role = 0; role < 4; role++)
    {
        stripes[role].read_start = stripes[role].req_start;
        stripes[role].read_end = stripes[role].req_end;
    }
    assert(extend_missing_stripes(stripes, read_osd_set, 2, 4) == 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 128*1024);
    void *read_buf = alloc_read_buffer(stripes, 4, 0);
    for (int i = 0; i < 4; i++)
        stripes[i].bmp_buf = bitmaps+i;
    assert(read_buf);
    assert(stripes[0].read_buf == read_buf);
    assert(stripes[1].read_buf == (uint8_t*)read_buf+128*1024);
    assert(stripes[3].read_buf == (uint8_t*)read_buf+2*128*1024);
    set_pattern(stripes[1].read_buf, 128*1024, PATTERN2);
    memcpy(stripes[3].read_buf, rmw_buf, 128*1024);
    memset(stripes[0].bmp_buf, 0xa8, bmp);
    memset(stripes[2].bmp_buf, 0xb7, bmp);
    assert(bitmaps[1] == 0xFFFFFFFF);
    assert(bitmaps[3] == 0xF1F1F1F1);
    reconstruct_stripes_ec(stripes, 4, 2, bmp);
    assert(*(uint32_t*)stripes[3].bmp_buf == 0xF1F1F1F1);
    assert(bitmaps[0] == 0xFFFFFFFF);
    check_pattern(stripes[0].read_buf, 128*1024, PATTERN1);
    free(read_buf);
    // Done
    free(rmw_buf);
    free(write_buf);
    use_ec(4, 2, false);
}

/***

17. EC 2+2 recover second data block

***/

void test_recover_22_d2()
{
    const int bmp = 128*1024 / 4096 / 8;
    use_ec(4, 2, true);
    osd_num_t osd_set[4] = { 1, 0, 3, 4 };
    osd_rmw_stripe_t stripes[4] = {};
    unsigned bitmaps[4] = { 0 };
    // Read 0-256K
    split_stripes(2, 128*1024, 0, 256*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 128*1024);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    uint8_t *data_buf = (uint8_t*)malloc_or_die(128*1024*4);
    for (int i = 0; i < 4; i++)
    {
        stripes[i].read_start = stripes[i].req_start;
        stripes[i].read_end = stripes[i].req_end;
        stripes[i].read_buf = data_buf + i*128*1024;
        stripes[i].bmp_buf = bitmaps + i;
    }
    // Read using parity
    assert(extend_missing_stripes(stripes, osd_set, 2, 4) == 0);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 0);
    bitmaps[0] = 0xffffffff;
    bitmaps[2] = 0;
    set_pattern(stripes[0].read_buf, 128*1024, PATTERN1);
    set_pattern(stripes[2].read_buf, 128*1024, PATTERN1^PATTERN2);
    // Reconstruct
    reconstruct_stripes_ec(stripes, 4, 2, bmp);
    check_pattern(stripes[1].read_buf, 128*1024, PATTERN2);
    assert(bitmaps[1] == 0xFFFFFFFF);
    free(data_buf);
    // Done
    use_ec(4, 2, false);
}

/***

18. EC 4+2 error location bruteforce

***/

static void assert_eq_vec(const std::vector<int> & b, const std::vector<int> & a)
{
    printf("Expect [");
    for (int i = 0; i < a.size(); i++)
        printf(" %d", a[i]);
    printf(" ] have [");
    for (int i = 0; i < b.size(); i++)
        printf(" %d", b[i]);
    printf(" ]\n");
    assert(a == b);
}

void test_ec43_error_bruteforce()
{
    use_ec(7, 4, true);
    osd_num_t osd_set[7] = { 1, 2, 3, 4, 5, 6, 7 };
    osd_rmw_stripe_t stripes[7] = {};
    split_stripes(4, 4096, 0, 4096 * 4, stripes);
    uint8_t *write_buf = (uint8_t*)malloc_or_die(4096 * 7);
    set_pattern(write_buf+0*4096, 4096, PATTERN0);
    set_pattern(write_buf+1*4096, 4096, PATTERN1);
    set_pattern(write_buf+2*4096, 4096, PATTERN2);
    set_pattern(write_buf+3*4096, 4096, PATTERN3);
    uint8_t *rmw_buf = (uint8_t*)calc_rmw(write_buf, stripes, osd_set, 7, 4, 7, osd_set, 4096, 0);
    calc_rmw_parity_ec(stripes, 7, 4, osd_set, osd_set, 4096, 0);
    check_pattern(stripes[4].write_buf, 4096, PATTERN0^PATTERN1^PATTERN2^PATTERN3);
    check_pattern(stripes[5].write_buf, 4096, 0xfcee568ba36371ac); // 2nd EC chunk
    check_pattern(stripes[6].write_buf, 4096, 0x139274739ae6f387); // 3rd EC chunk
    memcpy(write_buf+4*4096, stripes[4].write_buf, 4096);
    memcpy(write_buf+5*4096, stripes[5].write_buf, 4096);
    memcpy(write_buf+6*4096, stripes[6].write_buf, 4096);
    // Try to locate errors
    for (int i = 0; i < 7; i++)
    {
        stripes[i].read_start = 0;
        stripes[i].read_end = 4096;
        stripes[i].read_buf = write_buf+i*4096;
        stripes[i].write_buf = NULL;
    }
    // All good chunks
    auto res = ec_find_good(stripes, 7, 4, false, 4096, 0, 100);
    assert_eq_vec(res, std::vector<int>({0, 1, 2, 3, 4, 5, 6}));
    // 1 missing chunk
    set_pattern(write_buf+1*4096, 4096, 0);
    res = ec_find_good(stripes, 7, 4, false, 4096, 0, 100);
    assert_eq_vec(res, std::vector<int>({0, 2, 3, 4, 5, 6}));
    // 2 missing chunks
    set_pattern(write_buf+1*4096, 4096, 0);
    set_pattern(write_buf+5*4096, 4096, 0);
    res = ec_find_good(stripes, 7, 4, false, 4096, 0, 100);
    assert_eq_vec(res, std::vector<int>({0, 2, 3, 4, 6}));
    // 3 missing chunks
    set_pattern(write_buf+1*4096, 4096, 0);
    set_pattern(write_buf+5*4096, 4096, 0);
    set_pattern(write_buf+6*4096, 4096, 0);
    res = ec_find_good(stripes, 7, 4, false, 4096, 0, 100);
    assert_eq_vec(res, std::vector<int>());
    // Done
    free(rmw_buf);
    free(write_buf);
    use_ec(7, 4, false);
}

/***

19. EC 5+3 recover 5th data block but not 4th

***/

void test_recover_53_d5()
{
    const int bmp = 128*1024 / 4096 / 8;
    use_ec(8, 5, true);
    osd_num_t osd_set[8] = { 1, 2, 3, 0, 0, 6, 7, 8 };
    osd_rmw_stripe_t stripes[8] = {};
    unsigned bitmaps[8] = { 0 };
    // Read 512+128K
    split_stripes(5, 128*1024, 512*1024, 128*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 0);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 0);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    assert(stripes[4].req_start == 0 && stripes[4].req_end == 128*1024);
    uint8_t *data_buf = (uint8_t*)malloc_or_die(128*1024*8);
    for (int i = 0; i < 8; i++)
    {
        stripes[i].read_start = stripes[i].req_start;
        stripes[i].read_end = stripes[i].req_end;
        stripes[i].read_buf = data_buf + i*128*1024;
        stripes[i].bmp_buf = bitmaps + i;
    }
    // Read using parity
    assert(extend_missing_stripes(stripes, osd_set, 5, 8) == 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 0);
    assert(stripes[4].read_start == 0 && stripes[4].read_end == 128*1024);
    assert(stripes[5].read_start == 0 && stripes[5].read_end == 128*1024);
    assert(stripes[6].read_start == 0 && stripes[6].read_end == 128*1024);
    assert(stripes[7].read_start == 0 && stripes[7].read_end == 0);
    bitmaps[0] = 0xffffffff;
    bitmaps[1] = 0xffffffff;
    bitmaps[2] = 0xffffffff;
    bitmaps[3] = 0;
    bitmaps[4] = 0;
    bitmaps[5] = 0xffffffff;
    bitmaps[6] = 0x64646464;
    bitmaps[7] = 0;
    set_pattern(stripes[0].read_buf, 128*1024, 0x70a549add9a2280a);
    set_pattern(stripes[1].read_buf, 128*1024, 0xa70a549add9a2280);
    set_pattern(stripes[2].read_buf, 128*1024, 0x0a70a549add9a228);
    set_pattern(stripes[3].read_buf, 128*1024, 0); // 0x80a70a549add9a22
    set_pattern(stripes[4].read_buf, 128*1024, 0); // 0x280a70a549add9a2
    set_pattern(stripes[5].read_buf, 128*1024, 0x7572c28f7a91eb22); // xor
    set_pattern(stripes[6].read_buf, 128*1024, 0xb4542b32a560fe26); // 2nd EC chunk
    set_pattern(stripes[7].read_buf, 128*1024, 0);
    // Reconstruct
    reconstruct_stripes_ec(stripes, 8, 5, bmp);
    check_pattern(stripes[4].read_buf, 128*1024, 0x280a70a549add9a2);
    assert(bitmaps[4] == 0xFFFFFFFF);
    free(data_buf);
    // Done
    use_ec(8, 5, false);
}

void test_recover_22()
{
    const int bmp = 128*1024 / 4096 / 8;
    use_ec(4, 2, true);
    osd_num_t osd_set[4] = { 1, 2, 3, 4 };
    osd_num_t write_osd_set[4] = { 5, 0, 3, 0 };
    osd_rmw_stripe_t stripes[4] = {};
    unsigned bitmaps[4] = { 0 };
    // split
    void *write_buf = (uint8_t*)malloc_or_die(4096);
    set_pattern(write_buf, 4096, PATTERN0);
    split_stripes(2, 128*1024, 120*1024, 4096, stripes);
    assert(stripes[0].req_start == 120*1024 && stripes[0].req_end == 124*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 0);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    // calc_rmw
    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 4, 2, 2, write_osd_set, 128*1024, bmp);
    for (int i = 0; i < 4; i++)
        stripes[i].bmp_buf = bitmaps+i;
    assert(rmw_buf);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 120*1024 && stripes[1].read_end == 124*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 0);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 0);
    assert(stripes[0].write_start == 120*1024 && stripes[0].write_end == 124*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 120*1024 && stripes[2].write_end == 124*1024);
    assert(stripes[3].write_start == 0 && stripes[3].write_end == 0);
    assert(stripes[0].read_buf == (uint8_t*)rmw_buf+4*1024);
    assert(stripes[1].read_buf == (uint8_t*)rmw_buf+132*1024);
    assert(stripes[2].read_buf == NULL);
    assert(stripes[3].read_buf == NULL);
    assert(stripes[0].write_buf == write_buf);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == (uint8_t*)rmw_buf);
    assert(stripes[3].write_buf == NULL);
    // encode
    set_pattern(stripes[0].read_buf, 128*1024, PATTERN1);
    set_pattern(stripes[1].read_buf, 4*1024, PATTERN2);
    memset(stripes[0].bmp_buf, 0xff, bmp);
    memset(stripes[1].bmp_buf, 0xff, bmp);
    calc_rmw_parity_ec(stripes, 4, 2, osd_set, write_osd_set, 128*1024, bmp);
    assert(*(uint32_t*)stripes[2].bmp_buf == 0);
    assert(stripes[0].write_start == 0 && stripes[0].write_end == 128*1024);
    assert(stripes[1].write_start == 0 && stripes[1].write_end == 0);
    assert(stripes[2].write_start == 120*1024 && stripes[2].write_end == 124*1024);
    assert(stripes[3].write_start == 0 && stripes[3].write_end == 0);
    assert(stripes[0].write_buf == stripes[0].read_buf);
    assert(stripes[1].write_buf == NULL);
    assert(stripes[2].write_buf == (uint8_t*)rmw_buf);
    assert(stripes[3].write_buf == NULL);
    check_pattern(stripes[2].write_buf, 4*1024, PATTERN0^PATTERN2);
    // decode and verify
    memset(stripes, 0, sizeof(stripes));
    split_stripes(2, 128*1024, 0, 256*1024, stripes);
    assert(stripes[0].req_start == 0 && stripes[0].req_end == 128*1024);
    assert(stripes[1].req_start == 0 && stripes[1].req_end == 128*1024);
    assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
    assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
    for (int role = 0; role < 4; role++)
    {
        stripes[role].read_start = stripes[role].req_start;
        stripes[role].read_end = stripes[role].req_end;
    }
    assert(extend_missing_stripes(stripes, write_osd_set, 2, 4) == 0);
    assert(stripes[0].read_start == 0 && stripes[0].read_end == 128*1024);
    assert(stripes[1].read_start == 0 && stripes[1].read_end == 128*1024);
    assert(stripes[2].read_start == 0 && stripes[2].read_end == 128*1024);
    assert(stripes[3].read_start == 0 && stripes[3].read_end == 0);
    void *read_buf = alloc_read_buffer(stripes, 4, 0);
    for (int i = 0; i < 4; i++)
        stripes[i].bmp_buf = bitmaps+i;
    assert(read_buf);
    assert(stripes[0].read_buf == read_buf);
    assert(stripes[1].read_buf == (uint8_t*)read_buf+128*1024);
    assert(stripes[2].read_buf == (uint8_t*)read_buf+2*128*1024);
    set_pattern(stripes[0].read_buf, 128*1024, PATTERN1);
    set_pattern(stripes[0].read_buf+120*1024, 4*1024, PATTERN0);
    set_pattern(stripes[2].read_buf, 128*1024, PATTERN1^PATTERN2);
    set_pattern(stripes[2].read_buf+120*1024, 4*1024, PATTERN0^PATTERN2);
    memset(stripes[0].bmp_buf, 0xff, bmp);
    memset(stripes[2].bmp_buf, 0, bmp);
    bitmaps[1] = 0;
    bitmaps[3] = 0;
    reconstruct_stripes_ec(stripes, 4, 2, bmp);
    assert(bitmaps[0] == 0xFFFFFFFF);
    assert(*(uint32_t*)stripes[1].bmp_buf == 0xFFFFFFFF);
    check_pattern(stripes[1].read_buf, 128*1024, PATTERN2);
    free(read_buf);
    // Done
    free(rmw_buf);
    free(write_buf);
    use_ec(4, 2, false);
}