Files
littlefs/bd/lfs3_emubd.c
T
Christopher Haster 3db2bb980b runners: emubd/kiwibd: Adopted lower-level bus+buffer bd sim
After letting it sit for a bit, the previous byte+op sim comes across as
overly clever in a way that is counter-productive. This is highlighted
by erase-timing scaling in a confusing way when per-op.

Fortunately, with a bit of tweaking, we can instead model the bd sim as
separate bus+buffer timings. This seems more intuitive and is closer to
how the actual hardware works.

---

In the bus+buffer model, bd operations are simulated using two sets of
timing estimates:

  buffer timings (nor)          bus timings (nor)
  read_timing (0)               readed_timing (40 ns/B)
  prog_timing (1563 ns/B)       progged_timing (19 ns/B)
  erase_timing (10986 ns/B)     erased_timing (0)

Bus timings are a simple multiplier of the bytes read/progged/erased,
while buffer timings are rounded up + aligned to the nearest "width":

  bd geometry (nor)             bd buffers (nor)
  read_size (1 B)               read_width (1 B)
  prog_size (1 B)               prog_width (256 B)
  erase_size (4096 B)           erase_width (4096 B)

For most purposes, the width should just be the device's read/prog/erase
buffer, but I went with the name width to try to keep it generic and
avoid confusion with "buffer" elsewhere in the codebase.

Some notes:

- Like the byte+op sim, the bus+buffer sim allows penalizing small
  operations without artificially limiting what operations are possible.

- Because buffer timings depend on read/prog/erase alignment, there's no
  simple equation from ops+bytes to bus+buffer. But as a tradeoff, this
  new sim more accurately penalizes unaligned operations.

- All timings are still kept as per-byte instead of per-width. This has
  proven to be more flexible when benchmarking, as you usually what
  timings to scale with the relevant operation.

- Currently this implemented by changing reads/progs/erases to track the
  number of "widths" read/progged/erased after alignment. Which makes
  the simtime formula roughly:

    simtime = reads*read_width*read_timing + readed*readed_timing
              (per-butter)                   (per-bus)

  I considered keeping separate counters for calls (read_calls/
  prog_calls/erase_calls?), but not sure there's a good reason to. The
  theory behind these widths is there no functional difference between
  one big call vs multiple width sized calls, though maybe they would be
  useful for debugging?

  We can always add these later if they turn out to be useful.

- When widths are disable (0), reads/progs/erases reverts to the number
  of read/prog/erase calls.

  This is the behavior when BENCH_SIMPLE is defined at compile-time.
2026-03-09 22:50:29 -05:00

1540 lines
50 KiB
C

/*
* emubd - High-level emulating block device with many bells and
* whistles for testing powerloss, wear, etc.
*
* Note emubd always backs the block device in RAM. Consider using
* kiwibd if you need a block device larger than the available RAM on
* the system.
*
* Copyright (c) 2022, The littlefs authors.
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
*/
#ifndef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE 199309L
#endif
#include "bd/lfs3_emubd.h"
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <time.h>
#ifdef _WIN32
#include <windows.h>
#endif
// low-level flash memory emulation
// read data
static inline void lfs3_emubd_memread(const struct lfs3_cfg *cfg,
void *restrict dst, const void *restrict src, size_t size) {
(void)cfg;
memcpy(dst, src, size);
}
static inline void lfs3_emubd_memprog(const struct lfs3_cfg *cfg,
void *restrict dst, const void *restrict src, size_t size) {
lfs3_emubd_t *bd = cfg->context;
// emulating nor-masking?
if (bd->cfg->erase_value == -2) {
uint8_t *dst_ = dst;
const uint8_t *src_ = src;
for (size_t i = 0; i < size; i++) {
dst_[i] &= src_[i];
}
} else {
memcpy(dst, src, size);
}
}
static inline void lfs3_emubd_memerase(const struct lfs3_cfg *cfg,
void *restrict dst, size_t size) {
lfs3_emubd_t *bd = cfg->context;
// emulating erase value?
if (bd->cfg->erase_value != -1) {
memset(dst,
(bd->cfg->erase_value >= 0)
? bd->cfg->erase_value
: 0xff,
size);
}
}
// this is slightly different from lfs3_emubd_memerase in that we use
// lfs3_emubd_memzero when we need to unconditionally zero memory
static inline void lfs3_emubd_memzero(const struct lfs3_cfg *cfg,
void *restrict dst, size_t size) {
lfs3_emubd_t *bd = cfg->context;
memset(dst,
(bd->cfg->erase_value == -1) ? 0
: (bd->cfg->erase_value >= 0) ? bd->cfg->erase_value
: (bd->cfg->erase_value == -2) ? 0xff
: 0,
size);
}
// access to lazily-allocated/copy-on-write blocks
//
// note we can only modify a block if we have exclusive access to
// it (rc == 1)
//
static lfs3_emubd_block_t *lfs3_emubd_incblock(lfs3_emubd_block_t *block) {
if (block) {
block->rc += 1;
}
return block;
}
static void lfs3_emubd_decblock(lfs3_emubd_block_t *block) {
if (block) {
block->rc -= 1;
if (block->rc == 0) {
free(block);
}
}
}
static lfs3_emubd_block_t *lfs3_emubd_mutblock(
const struct lfs3_cfg *cfg,
lfs3_emubd_block_t *block) {
if (block && block->rc == 1) {
// rc == 1? can modify
return block;
} else if (block) {
// rc > 1? need to create a copy
lfs3_emubd_block_t *block_ = malloc(
sizeof(lfs3_emubd_block_t) + cfg->block_size);
if (!block_) {
return NULL;
}
memcpy(block_, block,
sizeof(lfs3_emubd_block_t) + cfg->block_size);
block_->rc = 1;
lfs3_emubd_decblock(block);
return block_;
} else {
// no block? need to allocate
lfs3_emubd_block_t *block_ = malloc(
sizeof(lfs3_emubd_block_t) + cfg->block_size);
if (!block_) {
return NULL;
}
block_->rc = 1;
block_->wear = 0;
block_->metastable = false;
block_->bad_bit = 0;
// zero for consistency
lfs3_emubd_memzero(cfg, block_->data, cfg->block_size);
return block_;
}
}
// prng used for some emulation things
static uint32_t lfs3_emubd_prng_(uint32_t *state) {
// A simple xorshift32 generator, easily reproducible. Keep in mind
// determinism is much more important than actual randomness here.
uint32_t x = *state;
// must be non-zero, use uintmax here so that seed=0 is different
// from seed=1 and seed=range(0,n) makes a bit more sense
if (x == 0) {
x = -1;
}
x ^= x << 13;
x ^= x >> 17;
x ^= x << 5;
*state = x;
return x;
}
// emubd create/destroy
int lfs3_emubd_createcfg(const struct lfs3_cfg *cfg, const char *path,
const struct lfs3_emubd_cfg *bdcfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_createcfg("
"%p {"
".context=%p, "
".read=%p, "
".prog=%p, "
".erase=%p, "
".sync=%p, "
".read_size=%"PRIu32", "
".prog_size=%"PRIu32", "
".block_size=%"PRIu32", "
".block_count=%"PRIu32"}, "
"\"%s\", "
"%p {.erase_value=%"PRId32", "
".erase_cycles=%"PRIu32", "
".badblock_behavior=%"PRIu8", "
".power_cycles=%"PRIu32", "
".powerloss_behavior=%"PRIu8", "
".powerloss_cb=%p, "
".powerloss_data=%p, "
".seed=%"PRIu32", "
".read_sleep=%"PRIu64", "
".prog_sleep=%"PRIu64", "
".erase_sleep=%"PRIu64"})",
(void*)cfg,
cfg->context,
(void*)(uintptr_t)cfg->read,
(void*)(uintptr_t)cfg->prog,
(void*)(uintptr_t)cfg->erase,
(void*)(uintptr_t)cfg->sync,
cfg->read_size,
cfg->prog_size,
cfg->block_size,
cfg->block_count,
path,
(void*)bdcfg,
bdcfg->erase_value,
bdcfg->erase_cycles,
bdcfg->badblock_behavior,
bdcfg->power_cycles,
bdcfg->powerloss_behavior,
(void*)(uintptr_t)bdcfg->powerloss_cb,
bdcfg->powerloss_data,
bdcfg->seed,
bdcfg->read_sleep,
bdcfg->prog_sleep,
bdcfg->erase_sleep);
lfs3_emubd_t *bd = cfg->context;
bd->cfg = bdcfg;
// setup testing things
bd->blocks = NULL;
bd->reads = 0;
bd->progs = 0;
bd->erases = 0;
bd->readed = 0;
bd->progged = 0;
bd->erased = 0;
bd->prng = bd->cfg->seed;
bd->power_cycles = bd->cfg->power_cycles;
bd->ooo_before = NULL;
bd->ooo_after = NULL;
bd->disk = NULL;
// allocate our block array, all blocks start as uninitialized
bd->blocks = malloc(
cfg->block_count * sizeof(lfs3_emubd_block_t*));
int err;
if (!bd->blocks) {
err = LFS3_ERR_NOMEM;
goto failed;
}
memset(bd->blocks, 0,
cfg->block_count * sizeof(lfs3_emubd_block_t*));
// allocate extra block arrays to hold our ooo snapshots
if (bd->cfg->powerloss_behavior == LFS3_EMUBD_POWERLOSS_OOO) {
bd->ooo_before = malloc(
cfg->block_count * sizeof(lfs3_emubd_block_t*));
if (!bd->ooo_before) {
err = LFS3_ERR_NOMEM;
goto failed;
}
memset(bd->ooo_before, 0,
cfg->block_count * sizeof(lfs3_emubd_block_t*));
bd->ooo_after = malloc(
cfg->block_count * sizeof(lfs3_emubd_block_t*));
if (!bd->ooo_after) {
err = LFS3_ERR_NOMEM;
goto failed;
}
memset(bd->ooo_after, 0,
cfg->block_count * sizeof(lfs3_emubd_block_t*));
}
if (path) {
bd->disk = malloc(sizeof(lfs3_emubd_disk_t));
if (!bd->disk) {
err = LFS3_ERR_NOMEM;
goto failed;
}
bd->disk->rc = 1;
bd->disk->fd = -1;
bd->disk->scratch = NULL;
#ifdef _WIN32
bd->disk->fd = open(path, O_RDWR | O_CREAT | O_BINARY, 0666);
#else
bd->disk->fd = open(path, O_RDWR | O_CREAT, 0666);
#endif
if (bd->disk->fd < 0) {
err = -errno;
goto failed;
}
bd->disk->scratch = malloc(cfg->block_size);
if (!bd->disk->scratch) {
err = LFS3_ERR_NOMEM;
goto failed;
}
lfs3_emubd_memzero(cfg, bd->disk->scratch, cfg->block_size);
// go ahead and erase all of the disk, otherwise the file will not
// match our internal representation
for (size_t i = 0; i < cfg->block_count; i++) {
ssize_t res = write(bd->disk->fd,
bd->disk->scratch,
cfg->block_size);
if (res < 0) {
err = -errno;
goto failed;
}
}
}
LFS3_EMUBD_TRACE("lfs3_emubd_createcfg -> %d", 0);
return 0;
failed:;
LFS3_EMUBD_TRACE("lfs3_emubd_createcfg -> %d", err);
// clean up memory
free(bd->blocks);
if (bd->cfg->powerloss_behavior == LFS3_EMUBD_POWERLOSS_OOO) {
free(bd->ooo_before);
free(bd->ooo_after);
}
if (bd->disk) {
if (bd->disk->fd != -1) {
close(bd->disk->fd);
}
free(bd->disk->scratch);
free(bd->disk);
}
return err;
}
int lfs3_emubd_create(const struct lfs3_cfg *cfg, const char *path) {
LFS3_EMUBD_TRACE("lfs3_emubd_create("
"%p {"
".context=%p, "
".read=%p, "
".prog=%p, "
".erase=%p, "
".sync=%p, "
".read_size=%"PRIu32", "
".prog_size=%"PRIu32", "
".block_size=%"PRIu32", "
".block_count=%"PRIu32"}, "
"\"%s\")",
(void*)cfg,
cfg->context,
(void*)(uintptr_t)cfg->read,
(void*)(uintptr_t)cfg->prog,
(void*)(uintptr_t)cfg->erase,
(void*)(uintptr_t)cfg->sync,
cfg->read_size,
cfg->prog_size,
cfg->block_size,
cfg->block_count,
path);
static const struct lfs3_emubd_cfg defaults = {.erase_value=-1};
int err = lfs3_emubd_createcfg(cfg, path, &defaults);
LFS3_EMUBD_TRACE("lfs3_emubd_create -> %d", err);
return err;
}
int lfs3_emubd_destroy(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_destroy(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
// decrement reference counts
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
lfs3_emubd_decblock(bd->blocks[i]);
}
free(bd->blocks);
if (bd->cfg->powerloss_behavior == LFS3_EMUBD_POWERLOSS_OOO) {
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
lfs3_emubd_decblock(bd->ooo_before[i]);
}
free(bd->ooo_before);
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
lfs3_emubd_decblock(bd->ooo_after[i]);
}
free(bd->ooo_after);
}
// clean up other resources
if (bd->disk) {
bd->disk->rc -= 1;
if (bd->disk->rc == 0) {
close(bd->disk->fd);
free(bd->disk->scratch);
free(bd->disk);
}
}
LFS3_EMUBD_TRACE("lfs3_emubd_destroy -> %d", 0);
return 0;
}
// block device API
int lfs3_emubd_read(const struct lfs3_cfg *cfg, lfs3_block_t block,
lfs3_off_t off, void *buffer, lfs3_size_t size) {
LFS3_EMUBD_TRACE("lfs3_emubd_read(%p, "
"0x%"PRIx32", %"PRIu32", %p, %"PRIu32")",
(void*)cfg, block, off, buffer, size);
lfs3_emubd_t *bd = cfg->context;
// check if read is valid
LFS3_ASSERT(block < cfg->block_count);
LFS3_ASSERT(off % cfg->read_size == 0);
LFS3_ASSERT(size % cfg->read_size == 0);
LFS3_ASSERT(off+size <= cfg->block_size);
// get the block
const lfs3_emubd_block_t *b = bd->blocks[block];
if (b) {
// block bad?
if (b->wear > bd->cfg->erase_cycles) {
// erroring reads? error
if (bd->cfg->badblock_behavior
== LFS3_EMUBD_BADBLOCK_READERROR) {
LFS3_EMUBD_TRACE("lfs3_emubd_read -> %d", LFS3_ERR_CORRUPT);
return LFS3_ERR_CORRUPT;
}
}
// read data
lfs3_emubd_memread(cfg, buffer, &b->data[off], size);
// metastable? randomly decide if our bad bit flips
if (b->metastable) {
lfs3_size_t bit = b->bad_bit & 0x7fffffff;
if (bit/8 >= off
&& bit/8 < off+size
&& (lfs3_emubd_prng_(&bd->prng) & 1)) {
((uint8_t*)buffer)[(bit/8) - off] ^= 1 << (bit%8);
}
}
// no block yet
} else {
// zero for consistency
lfs3_emubd_memzero(cfg, buffer, size);
}
// track reads
bd->reads += (lfs3_alignup(off + size, lfs3_max(bd->cfg->read_width, 1))
- lfs3_aligndown(off, lfs3_max(bd->cfg->read_width, 1)))
/ lfs3_max(bd->cfg->read_width, 1);
bd->readed += size;
if (bd->cfg->read_sleep) {
int err = nanosleep(&(struct timespec){
.tv_sec=bd->cfg->read_sleep/1000000000,
.tv_nsec=bd->cfg->read_sleep%1000000000},
NULL);
if (err) {
err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_read -> %d", err);
return err;
}
}
LFS3_EMUBD_TRACE("lfs3_emubd_read -> %d", 0);
return 0;
}
int lfs3_emubd_prog(const struct lfs3_cfg *cfg, lfs3_block_t block,
lfs3_off_t off, const void *buffer, lfs3_size_t size) {
LFS3_EMUBD_TRACE("lfs3_emubd_prog(%p, "
"0x%"PRIx32", %"PRIu32", %p, %"PRIu32")",
(void*)cfg, block, off, buffer, size);
lfs3_emubd_t *bd = cfg->context;
// check if write is valid
LFS3_ASSERT(block < cfg->block_count);
LFS3_ASSERT(off % cfg->prog_size == 0);
LFS3_ASSERT(size % cfg->prog_size == 0);
LFS3_ASSERT(off+size <= cfg->block_size);
// were we erased properly?
LFS3_ASSERT(bd->blocks[block]);
if (bd->cfg->erase_value >= 0
&& bd->blocks[block]->wear <= bd->cfg->erase_cycles) {
for (lfs3_off_t i = 0; i < size; i++) {
LFS3_ASSERT(bd->blocks[block]->data[off+i] == bd->cfg->erase_value);
}
}
// losing power?
if (bd->power_cycles > 0) {
bd->power_cycles -= 1;
if (bd->power_cycles == 0) {
// emulating some bits? choose a random bit to flip
if (bd->cfg->powerloss_behavior
== LFS3_EMUBD_POWERLOSS_SOMEBITS) {
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg,
bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// flip bit
lfs3_size_t bit = lfs3_emubd_prng_(&bd->prng)
% (cfg->prog_size*8);
b->data[off + (bit/8)] ^= 1 << (bit%8);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size + (off_t)off,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd, &b->data[off], size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
}
// emulating most bits? prog data and choose a random bit
// to flip
} else if (bd->cfg->powerloss_behavior
== LFS3_EMUBD_POWERLOSS_MOSTBITS) {
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg,
bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// prog data
lfs3_emubd_memprog(cfg, &b->data[off], buffer, size);
// flip bit
lfs3_size_t bit = lfs3_emubd_prng_(&bd->prng)
% (cfg->prog_size*8);
b->data[off + (bit/8)] ^= 1 << (bit%8);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size + (off_t)off,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd, &b->data[off], size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
}
// emulating out-of-order writes? revert everything unsynced
// except for our current block
} else if (bd->cfg->powerloss_behavior
== LFS3_EMUBD_POWERLOSS_OOO) {
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
lfs3_emubd_decblock(bd->ooo_after[i]);
bd->ooo_after[i] = lfs3_emubd_incblock(bd->blocks[i]);
if (i != block && bd->blocks[i] != bd->ooo_before[i]) {
lfs3_emubd_decblock(bd->blocks[i]);
bd->blocks[i] = lfs3_emubd_incblock(bd->ooo_before[i]);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)i*cfg->block_size,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd,
(bd->blocks[i])
? bd->blocks[i]->data
: bd->disk->scratch,
cfg->block_size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
}
}
}
// emulating metastability? prog data, choose a random bad bit,
// and mark as metastable
} else if (bd->cfg->powerloss_behavior
== LFS3_EMUBD_POWERLOSS_METASTABLE) {
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg,
bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// prog data
lfs3_emubd_memprog(cfg, &b->data[off], buffer, size);
// choose a new bad bit unless overridden
if (!(0x80000000 & b->bad_bit)) {
b->bad_bit = lfs3_emubd_prng_(&bd->prng)
% (cfg->block_size*8);
}
// mark as metastable
b->metastable = true;
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size + (off_t)off,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd, &b->data[off], size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
}
}
// powerloss!
bd->cfg->powerloss_cb(bd->cfg->powerloss_data);
// oh, continuing? undo out-of-order write emulation
if (bd->cfg->powerloss_behavior == LFS3_EMUBD_POWERLOSS_OOO) {
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
if (bd->blocks[i] != bd->ooo_after[i]) {
lfs3_emubd_decblock(bd->blocks[i]);
bd->blocks[i] = lfs3_emubd_incblock(bd->ooo_after[i]);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)i*cfg->block_size,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd,
(bd->blocks[i])
? bd->blocks[i]->data
: bd->disk->scratch,
cfg->block_size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
}
}
}
}
}
}
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// block bad?
if (b->wear > bd->cfg->erase_cycles) {
// erroring progs? error
if (bd->cfg->badblock_behavior
== LFS3_EMUBD_BADBLOCK_PROGERROR) {
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", LFS3_ERR_CORRUPT);
return LFS3_ERR_CORRUPT;
// noop progs? skip
} else if (bd->cfg->badblock_behavior
== LFS3_EMUBD_BADBLOCK_PROGNOOP
|| bd->cfg->badblock_behavior
== LFS3_EMUBD_BADBLOCK_ERASENOOP) {
goto progged;
// progs flipping bits? flip our bad bit, exactly which bit
// is chosen during erase
} else if (bd->cfg->badblock_behavior
== LFS3_EMUBD_BADBLOCK_PROGFLIP) {
lfs3_size_t bit = b->bad_bit & 0x7fffffff;
if (bit/8 >= off && bit/8 < off+size) {
// prog data
lfs3_emubd_memprog(cfg, &b->data[off], buffer, size);
b->data[bit/8] ^= 1 << (bit%8);
goto progged;
}
// reads flipping bits? prog as normal but mark as metastable
} else if (bd->cfg->badblock_behavior
== LFS3_EMUBD_BADBLOCK_READFLIP) {
// prog data
lfs3_emubd_memprog(cfg, &b->data[off], buffer, size);
b->metastable = true;
goto progged;
}
}
// prog data
lfs3_emubd_memprog(cfg, &b->data[off], buffer, size);
// clear any metastability
b->metastable = false;
progged:;
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size + (off_t)off,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd, &b->data[off], size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
}
// track progs
bd->progs += (lfs3_alignup(off + size, lfs3_max(bd->cfg->prog_width, 1))
- lfs3_aligndown(off, lfs3_max(bd->cfg->prog_width, 1)))
/ lfs3_max(bd->cfg->prog_width, 1);
bd->progged += size;
if (bd->cfg->prog_sleep) {
int err = nanosleep(&(struct timespec){
.tv_sec=bd->cfg->prog_sleep/1000000000,
.tv_nsec=bd->cfg->prog_sleep%1000000000},
NULL);
if (err) {
err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", err);
return err;
}
}
LFS3_EMUBD_TRACE("lfs3_emubd_prog -> %d", 0);
return 0;
}
int lfs3_emubd_erase(const struct lfs3_cfg *cfg, lfs3_block_t block) {
LFS3_EMUBD_TRACE("lfs3_emubd_erase(%p, 0x%"PRIx32" (%"PRIu32"))",
(void*)cfg, block, cfg->block_size);
lfs3_emubd_t *bd = cfg->context;
// check if erase is valid
LFS3_ASSERT(block < cfg->block_count);
// losing power?
if (bd->power_cycles > 0) {
bd->power_cycles -= 1;
if (bd->power_cycles == 0) {
// emulating some bits? choose a random bit to flip
if (bd->cfg->powerloss_behavior
== LFS3_EMUBD_POWERLOSS_SOMEBITS) {
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg,
bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// flip bit
lfs3_size_t bit = lfs3_emubd_prng_(&bd->prng)
% (cfg->block_size*8);
b->data[(bit/8)] ^= 1 << (bit%8);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd,
b->data, cfg->block_size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
}
// emulating most bits? erase data and choose a random bit
// to flip
} else if (bd->cfg->powerloss_behavior
== LFS3_EMUBD_POWERLOSS_MOSTBITS) {
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg,
bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// emulate an erase value?
if (bd->cfg->erase_value != -1) {
lfs3_emubd_memerase(cfg, b->data, cfg->block_size);
}
// flip bit
lfs3_size_t bit = lfs3_emubd_prng_(&bd->prng)
% (cfg->block_size*8);
b->data[(bit/8)] ^= 1 << (bit%8);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd,
b->data, cfg->block_size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
}
// emulating out-of-order writes? revert everything unsynced
// except for our current block
} else if (bd->cfg->powerloss_behavior
== LFS3_EMUBD_POWERLOSS_OOO) {
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
if (i != block && bd->blocks[i] != bd->ooo_before[i]) {
lfs3_emubd_decblock(bd->blocks[i]);
bd->blocks[i] = lfs3_emubd_incblock(bd->ooo_before[i]);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)i*cfg->block_size,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd,
(bd->blocks[i])
? bd->blocks[i]->data
: bd->disk->scratch,
cfg->block_size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
}
}
}
// emulating metastability? erase data, choose a random bad bit,
// and mark as metastable
} else if (bd->cfg->powerloss_behavior
== LFS3_EMUBD_POWERLOSS_METASTABLE) {
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg,
bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// emulate an erase value?
if (bd->cfg->erase_value != -1) {
lfs3_emubd_memerase(cfg, b->data, cfg->block_size);
}
// choose a new bad bit unless overridden
if (!(0x80000000 & b->bad_bit)) {
b->bad_bit = lfs3_emubd_prng_(&bd->prng)
% (cfg->block_size*8);
}
// mark as metastable
b->metastable = true;
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd,
b->data, cfg->block_size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
}
}
// powerloss!
bd->cfg->powerloss_cb(bd->cfg->powerloss_data);
// oh, continuing? undo out-of-order write emulation
if (bd->cfg->powerloss_behavior == LFS3_EMUBD_POWERLOSS_OOO) {
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
if (bd->blocks[i] != bd->ooo_after[i]) {
lfs3_emubd_decblock(bd->blocks[i]);
bd->blocks[i] = lfs3_emubd_incblock(bd->ooo_after[i]);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)i*cfg->block_size,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd,
(bd->blocks[i])
? bd->blocks[i]->data
: bd->disk->scratch,
cfg->block_size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
}
}
}
}
}
}
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// keep track of wear
if (bd->cfg->erase_cycles && b->wear <= bd->cfg->erase_cycles) {
b->wear += 1;
}
// block bad?
if (b->wear > bd->cfg->erase_cycles) {
// erroring erases? error
if (bd->cfg->badblock_behavior
== LFS3_EMUBD_BADBLOCK_ERASEERROR) {
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", LFS3_ERR_CORRUPT);
return LFS3_ERR_CORRUPT;
// noop erases? skip
} else if (bd->cfg->badblock_behavior
== LFS3_EMUBD_BADBLOCK_ERASENOOP) {
goto erased;
// flipping bits? if we're not manually overridden, choose a
// new bad bit on erase, this makes it more likely to
// eventually cause problems
} else {
if (!(0x80000000 & b->bad_bit)) {
b->bad_bit = lfs3_emubd_prng_(&bd->prng)
% (cfg->block_size*8);
}
}
}
// emulate an erase value?
if (bd->cfg->erase_value != -1) {
lfs3_emubd_memerase(cfg, b->data, cfg->block_size);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size,
SEEK_SET);
if (res1 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
ssize_t res2 = write(bd->disk->fd, b->data, cfg->block_size);
if (res2 < 0) {
int err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
}
}
// clear any metastability
b->metastable = false;
erased:;
// track erases
bd->erases += lfs3_alignup(cfg->block_size,
lfs3_max(bd->cfg->erase_width, 1))
/ lfs3_max(bd->cfg->erase_width, 1);
bd->erased += cfg->block_size;
if (bd->cfg->erase_sleep) {
int err = nanosleep(&(struct timespec){
.tv_sec=bd->cfg->erase_sleep/1000000000,
.tv_nsec=bd->cfg->erase_sleep%1000000000},
NULL);
if (err) {
err = -errno;
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", err);
return err;
}
}
LFS3_EMUBD_TRACE("lfs3_emubd_erase -> %d", 0);
return 0;
}
int lfs3_emubd_sync(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_sync(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
// emulate out-of-order writes? save a snapshot on sync
if (bd->cfg->powerloss_behavior == LFS3_EMUBD_POWERLOSS_OOO) {
for (size_t i = 0; i < cfg->block_count; i++) {
lfs3_emubd_decblock(bd->ooo_before[i]);
bd->ooo_before[i] = lfs3_emubd_incblock(bd->blocks[i]);
}
}
LFS3_EMUBD_TRACE("lfs3_emubd_sync -> %d", 0);
return 0;
}
/// Additional emubd features for testing ///
lfs3_emubd_sns_t lfs3_emubd_simtime(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_simtime(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
// error if all possible timings are zero
if (bd->cfg->read_timing == 0
&& bd->cfg->prog_timing == 0
&& bd->cfg->erase_timing == 0
&& bd->cfg->readed_timing == 0
&& bd->cfg->progged_timing == 0
&& bd->cfg->erased_timing == 0) {
LFS3_EMUBD_TRACE("lfs3_emubd_simtime -> %d", LFS3_ERR_NOTSUP);
return LFS3_ERR_NOTSUP;
}
lfs3_emubd_ns_t ns
= (bd->cfg->read_timing * bd->reads*bd->cfg->read_width)
+ (bd->cfg->prog_timing * bd->progs*bd->cfg->prog_width)
+ (bd->cfg->erase_timing * bd->erases*bd->cfg->erase_width)
+ (bd->cfg->readed_timing * bd->readed)
+ (bd->cfg->progged_timing * bd->progged)
+ (bd->cfg->erased_timing * bd->erased);
LFS3_EMUBD_TRACE("lfs3_emubd_simtime -> %"PRIu64, ns);
return ns;
}
int lfs3_emubd_simreset(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_simreset(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
bd->reads = 0;
bd->progs = 0;
bd->erases = 0;
bd->readed = 0;
bd->progged = 0;
bd->erased = 0;
LFS3_EMUBD_TRACE("lfs3_emubd_simreset -> %d", 0);
return 0;
}
lfs3_emubd_sio_t lfs3_emubd_reads(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_reads(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
LFS3_EMUBD_TRACE("lfs3_emubd_reads -> %"PRIu64, bd->reads);
return bd->reads;
}
lfs3_emubd_sio_t lfs3_emubd_progs(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_progs(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
LFS3_EMUBD_TRACE("lfs3_emubd_progs -> %"PRIu64, bd->progs);
return bd->progs;
}
lfs3_emubd_sio_t lfs3_emubd_erases(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_erases(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
LFS3_EMUBD_TRACE("lfs3_emubd_erases -> %"PRIu64, bd->erases);
return bd->erases;
}
lfs3_emubd_sio_t lfs3_emubd_readed(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_readed(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
LFS3_EMUBD_TRACE("lfs3_emubd_readed -> %"PRIu64, bd->readed);
return bd->readed;
}
lfs3_emubd_sio_t lfs3_emubd_progged(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_progged(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
LFS3_EMUBD_TRACE("lfs3_emubd_progged -> %"PRIu64, bd->progged);
return bd->progged;
}
lfs3_emubd_sio_t lfs3_emubd_erased(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_erased(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
LFS3_EMUBD_TRACE("lfs3_emubd_erased -> %"PRIu64, bd->erased);
return bd->erased;
}
lfs3_emubd_swear_t lfs3_emubd_wear(const struct lfs3_cfg *cfg,
lfs3_block_t block) {
LFS3_EMUBD_TRACE("lfs3_emubd_wear(%p, %"PRIu32")", (void*)cfg, block);
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// get the wear
lfs3_emubd_wear_t wear;
const lfs3_emubd_block_t *b = bd->blocks[block];
if (b) {
wear = b->wear;
} else {
wear = 0;
}
LFS3_EMUBD_TRACE("lfs3_emubd_wear -> %"PRIi32, wear);
return wear;
}
int lfs3_emubd_setwear(const struct lfs3_cfg *cfg,
lfs3_block_t block, lfs3_emubd_wear_t wear) {
LFS3_EMUBD_TRACE("lfs3_emubd_setwear(%p, %"PRIu32", %"PRIi32")",
(void*)cfg, block, wear);
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_setwear -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// set the wear
b->wear = wear;
LFS3_EMUBD_TRACE("lfs3_emubd_setwear -> %d", 0);
return 0;
}
int lfs3_emubd_mkbad(const struct lfs3_cfg *cfg,
lfs3_block_t block) {
LFS3_EMUBD_TRACE("lfs3_emubd_mkbad(%p, %"PRIu32")",
(void*)cfg, block);
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_mkbad -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// set the wear
b->wear = -1;
// choose a bad bit now in case this block is never erased
if (!(0x80000000 & b->bad_bit)) {
b->bad_bit = lfs3_emubd_prng_(&bd->prng)
% (cfg->block_size*8);
}
LFS3_EMUBD_TRACE("lfs3_emubd_mkbad -> %d", 0);
return 0;
}
int lfs3_emubd_mkgood(const struct lfs3_cfg *cfg,
lfs3_block_t block) {
LFS3_EMUBD_TRACE("lfs3_emubd_mkgood(%p, %"PRIu32")",
(void*)cfg, block);
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_mkgood -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// set the wear
b->wear = 0;
LFS3_EMUBD_TRACE("lfs3_emubd_mkgood -> %d", 0);
return 0;
}
lfs3_ssize_t lfs3_emubd_badbit(const struct lfs3_cfg *cfg,
lfs3_block_t block) {
LFS3_EMUBD_TRACE("lfs3_emubd_badbit(%p, %"PRIu32")", (void*)cfg, block);
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// get the bad bit
lfs3_size_t bad_bit;
const lfs3_emubd_block_t *b = bd->blocks[block];
if (b) {
bad_bit = 0x7fffffff & b->bad_bit;
} else {
bad_bit = 0;
}
LFS3_EMUBD_TRACE("lfs3_emubd_badbit -> %"PRIi32, bad_bit);
return bad_bit;
}
int lfs3_emubd_setbadbit(const struct lfs3_cfg *cfg,
lfs3_block_t block, lfs3_size_t bit) {
LFS3_EMUBD_TRACE("lfs3_emubd_setbadbit(%p, %"PRIu32", %"PRIu32")",
(void*)cfg, block, bit);
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_setbadbit -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// set the bad bit and mark as fixed
b->bad_bit = 0x80000000 | bit;
LFS3_EMUBD_TRACE("lfs3_emubd_setbadbit -> %d", 0);
return 0;
}
int lfs3_emubd_randomizebadbit(const struct lfs3_cfg *cfg,
lfs3_block_t block) {
LFS3_EMUBD_TRACE("lfs3_emubd_randomizebadbit(%p, %"PRIu32")",
(void*)cfg, block);
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_randomizebadbit -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// mark the bad bit as randomized
b->bad_bit &= ~0x80000000;
LFS3_EMUBD_TRACE("lfs3_emubd_randomizebadbit -> %d", 0);
return 0;
}
int lfs3_emubd_mkbadbit(const struct lfs3_cfg *cfg,
lfs3_block_t block, lfs3_size_t bit) {
LFS3_EMUBD_TRACE("lfs3_emubd_mkbadbit(%p, %"PRIu32", %"PRIu32")",
(void*)cfg, block, bit);
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
LFS3_EMUBD_TRACE("lfs3_emubd_mkbadbit -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// set the wear
b->wear = -1;
// set the bad bit and mark as fixed
b->bad_bit = 0x80000000 | bit;
LFS3_EMUBD_TRACE("lfs3_emubd_mkbadbit -> %d", 0);
return 0;
}
int lfs3_emubd_flipbit_(const struct lfs3_cfg *cfg,
lfs3_block_t block, lfs3_size_t bit) {
lfs3_emubd_t *bd = cfg->context;
// check if block is valid
LFS3_ASSERT(block < cfg->block_count);
// mutate the block
lfs3_emubd_block_t *b = lfs3_emubd_mutblock(cfg, bd->blocks[block]);
if (!b) {
return LFS3_ERR_NOMEM;
}
bd->blocks[block] = b;
// flip the bit
b->data[bit/8] ^= 1 << (bit%8);
// mirror to disk file?
if (bd->disk) {
off_t res1 = lseek(bd->disk->fd,
(off_t)block*cfg->block_size + (off_t)(bit/8),
SEEK_SET);
if (res1 < 0) {
int err = -errno;
return err;
}
ssize_t res2 = write(bd->disk->fd, &b->data[bit/8], 1);
if (res2 < 0) {
int err = -errno;
return err;
}
}
return 0;
}
int lfs3_emubd_flipbit(const struct lfs3_cfg *cfg,
lfs3_block_t block, lfs3_size_t bit) {
LFS3_EMUBD_TRACE("lfs3_emubd_flipbit(%p, %"PRIu32", %"PRIu32")",
(void*)cfg, block, bit);
// flip the bit
int err = lfs3_emubd_flipbit_(cfg, block, bit);
if (err) {
LFS3_EMUBD_TRACE("lfs3_emubd_flipbit -> %d", err);
return err;
}
LFS3_EMUBD_TRACE("lfs3_emubd_flipbit -> %d", 0);
return 0;
}
int lfs3_emubd_flip(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_flip(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
// flip all bits in bad blocks, make sure not to allocate blocks we
// don't need
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
const lfs3_emubd_block_t *b = bd->blocks[i];
if (b && b->wear > bd->cfg->erase_cycles) {
int err = lfs3_emubd_flipbit_(cfg, i, b->bad_bit & 0x7fffffff);
if (err) {
LFS3_EMUBD_TRACE("lfs3_emubd_flip -> %d", err);
return err;
}
}
}
LFS3_EMUBD_TRACE("lfs3_emubd_flip -> %d", 0);
return 0;
}
lfs3_emubd_spowercycles_t lfs3_emubd_powercycles(
const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_powercycles(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
LFS3_EMUBD_TRACE("lfs3_emubd_powercycles -> %"PRIi32, bd->power_cycles);
return bd->power_cycles;
}
int lfs3_emubd_setpowercycles(const struct lfs3_cfg *cfg,
lfs3_emubd_powercycles_t power_cycles) {
LFS3_EMUBD_TRACE("lfs3_emubd_setpowercycles(%p, %"PRIi32")",
(void*)cfg, power_cycles);
lfs3_emubd_t *bd = cfg->context;
bd->power_cycles = power_cycles;
LFS3_EMUBD_TRACE("lfs3_emubd_powercycles -> %d", 0);
return 0;
}
void lfs3_emubd_seed(const struct lfs3_cfg *cfg, uint32_t seed) {
LFS3_EMUBD_TRACE("lfs3_emubd_seed(%p, 0x%08"PRIx32")",
(void*)cfg, seed);
lfs3_emubd_t *bd = cfg->context;
bd->prng = seed;
LFS3_EMUBD_TRACE("lfs3_emubd_seed -> _");
}
uint32_t lfs3_emubd_prng(const struct lfs3_cfg *cfg) {
LFS3_EMUBD_TRACE("lfs3_emubd_prng(%p)", (void*)cfg);
lfs3_emubd_t *bd = cfg->context;
uint32_t x = lfs3_emubd_prng_(&bd->prng);
LFS3_EMUBD_TRACE("lfs3_emubd_prng -> 0x%08"PRIx32, x);
return x;
}
int lfs3_emubd_cpy(const struct lfs3_cfg *cfg, lfs3_emubd_t *copy) {
LFS3_EMUBD_TRACE("lfs3_emubd_cpy(%p, %p)", (void*)cfg, (void*)copy);
lfs3_emubd_t *bd = cfg->context;
// lazily copy over our block array
copy->blocks = malloc(
cfg->block_count * sizeof(lfs3_emubd_block_t*));
if (!copy->blocks) {
LFS3_EMUBD_TRACE("lfs3_emubd_cpy -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
copy->blocks[i] = lfs3_emubd_incblock(bd->blocks[i]);
}
if (bd->cfg->powerloss_behavior == LFS3_EMUBD_POWERLOSS_OOO) {
copy->ooo_before = malloc(
cfg->block_count * sizeof(lfs3_emubd_block_t*));
if (!copy->ooo_before) {
LFS3_EMUBD_TRACE("lfs3_emubd_cpy -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
copy->ooo_before[i] = lfs3_emubd_incblock(bd->ooo_before[i]);
}
copy->ooo_after = malloc(
cfg->block_count * sizeof(lfs3_emubd_block_t*));
if (!copy->ooo_after) {
LFS3_EMUBD_TRACE("lfs3_emubd_cpy -> %d", LFS3_ERR_NOMEM);
return LFS3_ERR_NOMEM;
}
for (lfs3_block_t i = 0; i < cfg->block_count; i++) {
copy->ooo_after[i] = lfs3_emubd_incblock(bd->ooo_after[i]);
}
}
// other state
copy->reads = bd->reads;
copy->progs = bd->progs;
copy->erases = bd->erases;
copy->readed = bd->readed;
copy->progged = bd->progged;
copy->erased = bd->erased;
copy->prng = bd->prng;
copy->power_cycles = bd->power_cycles;
copy->disk = bd->disk;
if (copy->disk) {
copy->disk->rc += 1;
}
copy->cfg = bd->cfg;
LFS3_EMUBD_TRACE("lfs3_emubd_cpy -> %d", 0);
return 0;
}