/*
ChibiOS - Copyright (C) 2006..2018 Giovanni Di Sirio.
This file is part of ChibiOS.
ChibiOS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file hal_mfs.c
* @brief Managed Flash Storage module code.
* @details This module manages a flash partition as a generic storage where
* arbitrary data records can be created, updated, deleted and
* retrieved.<br>
* A managed partition is composed of two banks of equal size, a
* bank is composed of one or more erasable sectors, a sector is
* divided in writable pages.<br>
* The module handles flash wear leveling and recovery of damaged
* banks (where possible) caused by power loss during operations.
* Both operations are transparent to the user.
*
* @addtogroup HAL_MFS
* @{
*/
#include <string.h>
#include "hal.h"
#include "hal_mfs.h"
/*===========================================================================*/
/* Driver local definitions. */
/*===========================================================================*/
/**
* @brief Data record size aligned.
*/
#define ALIGNED_REC_SIZE(n) \
(flash_offset_t)MFS_ALIGN_NEXT(sizeof (mfs_data_header_t) + (size_t)(n))
/**
* @brief Data record header size aligned.
*/
#define ALIGNED_DHDR_SIZE \
ALIGNED_REC_SIZE(0)
/**
* @brief Aligned size of a type.
*/
#define ALIGNED_SIZEOF(t) \
(((sizeof (t) - 1U) | MFS_ALIGN_MASK) + 1U)
/**
* @brief Combines two values (0..3) in one (0..15).
*/
#define PAIR(a, b) (((unsigned)(a) << 2U) | (unsigned)(b))
/**
* @brief Error check helper.
*/
#define RET_ON_ERROR(err) do { \
mfs_error_t e = (err); \
if (e != MFS_NO_ERROR) { \
return e; \
} \
} while (false)
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local variables and types. */
/*===========================================================================*/
static const uint16_t crc16_table[256] = {
0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7,
0x8108, 0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF,
0x1231, 0x0210, 0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6,
0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE,
0x2462, 0x3443, 0x0420, 0x1401, 0x64E6, 0x74C7, 0x44A4, 0x5485,
0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D,
0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6, 0x5695, 0x46B4,
0xB75B, 0xA77A, 0x9719, 0x8738, 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC,
0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823,
0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969, 0xA90A, 0xB92B,
0x5AF5, 0x4AD4, 0x7AB7, 0x6A96, 0x1A71, 0x0A50, 0x3A33, 0x2A12,
0xDBFD, 0xCBDC, 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A,
0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03, 0x0C60, 0x1C41,
0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD, 0xAD2A, 0xBD0B, 0x8D68, 0x9D49,
0x7E97, 0x6EB6, 0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70,
0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A, 0x9F59, 0x8F78,
0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C, 0xC12D, 0xF14E, 0xE16F,
0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067,
0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C, 0xE37F, 0xF35E,
0x02B1, 0x1290, 0x22F3, 0x32D2, 0x4235, 0x5214, 0x6277, 0x7256,
0xB5EA, 0xA5CB, 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D,
0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
0xA7DB, 0xB7FA, 0x8799, 0x97B8, 0xE75F, 0xF77E, 0xC71D, 0xD73C,
0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634,
0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9, 0xB98A, 0xA9AB,
0x5844, 0x4865, 0x7806, 0x6827, 0x18C0, 0x08E1, 0x3882, 0x28A3,
0xCB7D, 0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A,
0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0, 0x2AB3, 0x3A92,
0xFD2E, 0xED0F, 0xDD6C, 0xCD4D, 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9,
0x7C26, 0x6C07, 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1,
0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA, 0x8FD9, 0x9FF8,
0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0
};
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
uint16_t crc16(uint16_t crc, const uint8_t *data, size_t n) {
while (n > 0U) {
crc = (crc << 8U) ^ crc16_table[(crc >> 8U) ^ (uint16_t)*data];
data++;
n--;
}
return crc;
}
static void mfs_state_reset(MFSDriver *mfsp) {
unsigned i;
mfsp->current_bank = MFS_BANK_0;
mfsp->current_counter = 0U;
mfsp->next_offset = 0U;
mfsp->used_space = 0U;
for (i = 0; i < MFS_CFG_MAX_RECORDS; i++) {
mfsp->descriptors[i].offset = 0U;
mfsp->descriptors[i].size = 0U;
}
}
static flash_offset_t mfs_flash_get_bank_offset(MFSDriver *mfsp,
mfs_bank_t bank) {
return bank == MFS_BANK_0 ? flashGetSectorOffset(mfsp->config->flashp,
mfsp->config->bank0_start) :
flashGetSectorOffset(mfsp->config->flashp,
mfsp->config->bank1_start);
}
/**
* @brief Flash read.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] offset flash offset
* @param[in] n number of bytes to be read
* @param[out] rp pointer to the data buffer
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_flash_read(MFSDriver *mfsp, flash_offset_t offset,
size_t n, uint8_t *rp) {
flash_error_t ferr;
ferr = flashRead(mfsp->config->flashp, offset, n, rp);
if (ferr != FLASH_NO_ERROR) {
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
return MFS_NO_ERROR;
}
/**
* @brief Flash write.
* @note If the option @p MFS_CFG_WRITE_VERIFY is enabled then the flash
* is also read back for verification.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] offset flash offset
* @param[in] n number of bytes to be written
* @param[in] wp pointer to the data buffer
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_flash_write(MFSDriver *mfsp,
flash_offset_t offset,
size_t n,
const uint8_t *wp) {
flash_error_t ferr;
ferr = flashProgram(mfsp->config->flashp, offset, n, wp);
if (ferr != FLASH_NO_ERROR) {
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
#if MFS_CFG_WRITE_VERIFY == TRUE
/* Verifying the written data by reading it back and comparing.*/
while (n > 0U) {
size_t chunk = n <= MFS_CFG_BUFFER_SIZE ? n : MFS_CFG_BUFFER_SIZE;
RET_ON_ERROR(mfs_flash_read(mfsp, offset, chunk, mfsp->buffer.data8));
if (memcmp((void *)mfsp->buffer.data8, (void *)wp, chunk)) {
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
n -= chunk;
offset += (flash_offset_t)chunk;
wp += chunk;
}
#endif
return MFS_NO_ERROR;
}
/**
* @brief Flash copy.
* @note If the option @p MFS_CFG_WRITE_VERIFY is enabled then the flash
* is also read back for verification.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] doffset destination flash offset
* @param[in] soffset source flash offset
* @param[in] n number of bytes to be copied
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_flash_copy(MFSDriver *mfsp,
flash_offset_t doffset,
flash_offset_t soffset,
uint32_t n) {
/* Splitting the operation in smaller operations because the buffer is
small.*/
while (n > 0U) {
/* Data size that can be written in a single program page operation.*/
size_t chunk = (size_t)(((doffset | (MFS_CFG_BUFFER_SIZE - 1U)) + 1U) -
doffset);
if (chunk > n) {
chunk = n;
}
RET_ON_ERROR(mfs_flash_read(mfsp, soffset, chunk, mfsp->buffer.data8));
RET_ON_ERROR(mfs_flash_write(mfsp, doffset, chunk, mfsp->buffer.data8));
/* Next page.*/
soffset += chunk;
doffset += chunk;
n -= chunk;
}
return MFS_NO_ERROR;
}
/**
* @brief Erases and verifies all sectors belonging to a bank.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] bank bank to be erased
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_bank_erase(MFSDriver *mfsp, mfs_bank_t bank) {
flash_sector_t sector, end;
if (bank == MFS_BANK_0) {
sector = mfsp->config->bank0_start;
end = mfsp->config->bank0_start + mfsp->config->bank0_sectors;
}
else {
sector = mfsp->config->bank1_start;
end = mfsp->config->bank1_start + mfsp->config->bank1_sectors;
}
while (sector < end) {
flash_error_t ferr;
ferr = flashStartEraseSector(mfsp->config->flashp, sector);
if (ferr != FLASH_NO_ERROR) {
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
ferr = flashWaitErase(mfsp->config->flashp);
if (ferr != FLASH_NO_ERROR) {
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
ferr = flashVerifyErase(mfsp->config->flashp, sector);
if (ferr != FLASH_NO_ERROR) {
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
sector++;
}
return MFS_NO_ERROR;
}
/**
* @brief Erases and verifies all sectors belonging to a bank.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] bank bank to be verified
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_bank_verify_erase(MFSDriver *mfsp, mfs_bank_t bank) {
flash_sector_t sector, end;
if (bank == MFS_BANK_0) {
sector = mfsp->config->bank0_start;
end = mfsp->config->bank0_start + mfsp->config->bank0_sectors;
}
else {
sector = mfsp->config->bank1_start;
end = mfsp->config->bank1_start + mfsp->config->bank1_sectors;
}
while (sector < end) {
flash_error_t ferr;
ferr = flashVerifyErase(mfsp->config->flashp, sector);
if (ferr == FLASH_ERROR_VERIFY) {
return MFS_ERR_NOT_ERASED;
}
if (ferr != FLASH_NO_ERROR) {
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
sector++;
}
return MFS_NO_ERROR;
}
/**
* @brief Writes the validation header in a bank.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] bank bank to be validated
* @param[in] cnt value for the flash usage counter
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_bank_write_header(MFSDriver *mfsp,
mfs_bank_t bank,
uint32_t cnt) {
flash_sector_t sector;
mfs_bank_header_t bhdr;
if (bank == MFS_BANK_0) {
sector = mfsp->config->bank0_start;
}
else {
sector = mfsp->config->bank1_start;
}
bhdr.fields.magic1 = MFS_BANK_MAGIC_1;
bhdr.fields.magic2 = MFS_BANK_MAGIC_2;
bhdr.fields.counter = cnt;
bhdr.fields.reserved1 = (uint16_t)mfsp->config->erased;
bhdr.fields.crc = crc16(0xFFFFU, bhdr.hdr8,
sizeof (mfs_bank_header_t) - sizeof (uint16_t));
return mfs_flash_write(mfsp,
flashGetSectorOffset(mfsp->config->flashp, sector),
sizeof (mfs_bank_header_t),
bhdr.hdr8);
}
/**
* @brief Checks integrity of the header in the shared buffer.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] bank bank identifier
* @return The header state.
*
* @notapi
*/
static mfs_bank_state_t mfs_bank_check_header(MFSDriver *mfsp) {
uint16_t crc;
if ((mfsp->buffer.bhdr.hdr32[0] == mfsp->config->erased) &&
(mfsp->buffer.bhdr.hdr32[1] == mfsp->config->erased) &&
(mfsp->buffer.bhdr.hdr32[2] == mfsp->config->erased) &&
(mfsp->buffer.bhdr.hdr32[3] == mfsp->config->erased)) {
return MFS_BANK_ERASED;
}
/* Checking header fields integrity.*/
if ((mfsp->buffer.bhdr.fields.magic1 != MFS_BANK_MAGIC_1) ||
(mfsp->buffer.bhdr.fields.magic2 != MFS_BANK_MAGIC_2) ||
(mfsp->buffer.bhdr.fields.counter == mfsp->config->erased) ||
(mfsp->buffer.bhdr.fields.reserved1 != (uint16_t)mfsp->config->erased)) {
return MFS_BANK_GARBAGE;
}
/* Verifying header CRC.*/
crc = crc16(0xFFFFU, mfsp->buffer.bhdr.hdr8,
sizeof (mfs_bank_header_t) - sizeof (uint16_t));
if (crc != mfsp->buffer.bhdr.fields.crc) {
return MFS_BANK_GARBAGE;
}
return MFS_BANK_OK;
}
/**
* @brief Scans blocks searching for records.
* @note The block integrity is strongly checked.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] bank the bank identifier
* @param[out] wflagp warning flag on anomalies
*
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_bank_scan_records(MFSDriver *mfsp,
mfs_bank_t bank,
bool *wflagp) {
flash_offset_t hdr_offset, start_offset, end_offset;
/* No warning by default.*/
*wflagp = false;
/* Boundaries.*/
start_offset = mfs_flash_get_bank_offset(mfsp, bank);
hdr_offset = start_offset + (flash_offset_t)ALIGNED_SIZEOF(mfs_bank_header_t);
end_offset = start_offset + mfsp->config->bank_size;
/* Scanning records until there is there is not enough space left for an
header.*/
while (hdr_offset < end_offset - ALIGNED_DHDR_SIZE) {
union {
mfs_data_header_t dhdr;
uint8_t data8[ALIGNED_SIZEOF(mfs_data_header_t)];
} u;
uint16_t crc;
/* Reading the current record header.*/
RET_ON_ERROR(mfs_flash_read(mfsp, hdr_offset,
sizeof (mfs_data_header_t),
u.data8));
/* Checking if the found header is in erased state.*/
if ((u.dhdr.hdr32[0] == mfsp->config->erased) &&
(u.dhdr.hdr32[1] == mfsp->config->erased) &&
(u.dhdr.hdr32[2] == mfsp->config->erased)) {
break;
}
/* It is not erased so checking for integrity.*/
if ((u.dhdr.fields.magic1 != MFS_HEADER_MAGIC_1) ||
(u.dhdr.fields.magic2 != MFS_HEADER_MAGIC_2) ||
(u.dhdr.fields.id < 1U) ||
(u.dhdr.fields.id > (uint32_t)MFS_CFG_MAX_RECORDS) ||
(u.dhdr.fields.size > end_offset - hdr_offset)) {
*wflagp = true;
break;
}
/* Finally checking the CRC, we need to perform it in chunks because
we have a limited buffer.*/
crc = 0xFFFFU;
if (u.dhdr.fields.size > 0U) {
flash_offset_t data = hdr_offset + sizeof (mfs_data_header_t);
uint32_t total = u.dhdr.fields.size;
while (total > 0U) {
uint32_t chunk = total > MFS_CFG_BUFFER_SIZE ? MFS_CFG_BUFFER_SIZE :
total;
/* Reading the data chunk.*/
RET_ON_ERROR(mfs_flash_read(mfsp, data, chunk, mfsp->buffer.data8));
/* CRC on the read data chunk.*/
crc = crc16(crc, &mfsp->buffer.data8[0], chunk);
/* Next chunk.*/
data += chunk;
total -= chunk;
}
}
if (crc != u.dhdr.fields.crc) {
/* If the CRC is invalid then this record is ignored but scanning
continues because there could be more valid records afterward.*/
*wflagp = true;
}
else {
/* Zero-sized records are erase markers.*/
if (u.dhdr.fields.size == 0U) {
mfsp->descriptors[u.dhdr.fields.id - 1U].offset = 0U;
mfsp->descriptors[u.dhdr.fields.id - 1U].size = 0U;
}
else {
mfsp->descriptors[u.dhdr.fields.id - 1U].offset = hdr_offset;
mfsp->descriptors[u.dhdr.fields.id - 1U].size = u.dhdr.fields.size;
}
}
/* On the next header.*/
hdr_offset = hdr_offset + ALIGNED_REC_SIZE(u.dhdr.fields.size);
}
/* Next writable offset.*/
mfsp->next_offset = hdr_offset;
return MFS_NO_ERROR;
}
/**
* @brief Determines the state of a bank.
* @note This function does not test the bank integrity by scanning
* the data area, it just checks the header.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] bank bank to be checked
* @param[out] statep bank state, it can be:
* - MFS_BANK_ERASED
* - MFS_BANK_GARBAGE
* - MFS_BANK_OK
* .
* @param[out] cntp bank counter
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_bank_get_state(MFSDriver *mfsp,
mfs_bank_t bank,
mfs_bank_state_t *statep,
uint32_t *cntp) {
/* Reading the current bank header.*/
RET_ON_ERROR(mfs_flash_read(mfsp, mfs_flash_get_bank_offset(mfsp, bank),
sizeof (mfs_bank_header_t),
mfsp->buffer.data8));
/* Getting the counter regardless of the bank state, it is only valid if
the state is MFS_BANK_OK.*/
*cntp = mfsp->buffer.bhdr.fields.counter;
/* Checking just the header.*/
*statep = mfs_bank_check_header(mfsp);
if (*statep == MFS_BANK_ERASED) {
mfs_error_t err;
/* Checking if the bank is really all erased.*/
err = mfs_bank_verify_erase(mfsp, bank);
if (err == MFS_ERR_NOT_ERASED) {
*statep = MFS_BANK_GARBAGE;
}
}
return MFS_NO_ERROR;
}
/**
* @brief Enforces a garbage collection.
* @details Storage data is compacted into a single bank.
*
* @param[out] mfsp pointer to the @p MFSDriver object
* @return The operation status.
*
* @notapi
*/
static mfs_error_t mfs_garbage_collect(MFSDriver *mfsp) {
unsigned i;
mfs_bank_t sbank, dbank;
flash_offset_t dest_offset;
sbank = mfsp->current_bank;
if (sbank == MFS_BANK_0) {
dbank = MFS_BANK_1;
}
else {
dbank = MFS_BANK_0;
}
/* Write address.*/
dest_offset = mfs_flash_get_bank_offset(mfsp, dbank) +
ALIGNED_SIZEOF(mfs_bank_header_t);
/* Copying the most recent record instances only.*/
for (i = 0; i < MFS_CFG_MAX_RECORDS; i++) {
uint32_t totsize = ALIGNED_REC_SIZE(mfsp->descriptors[i].size);
if (mfsp->descriptors[i].offset != 0) {
RET_ON_ERROR(mfs_flash_copy(mfsp, dest_offset,
mfsp->descriptors[i].offset,
totsize));
mfsp->descriptors[i].offset = dest_offset;
dest_offset += totsize;
}
}
/* New current bank.*/
mfsp->current_bank = dbank;
mfsp->current_counter += 1U;
mfsp->next_offset = dest_offset;
/* The header is written after the data.*/
RET_ON_ERROR(mfs_bank_write_header(mfsp, dbank, mfsp->current_counter));
/* The source bank is erased last.*/
RET_ON_ERROR(mfs_bank_erase(mfsp, sbank));
return MFS_NO_ERROR;
}
/**
* @brief Performs a flash partition mount attempt.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @return The operation status.
*
* @api
*/
static mfs_error_t mfs_try_mount(MFSDriver *mfsp) {
mfs_bank_state_t sts0, sts1;
mfs_bank_t bank;
uint32_t cnt0 = 0, cnt1 = 0;
bool w1 = false, w2 = false;
/* Resetting the bank state.*/
mfs_state_reset(mfsp);
/* Assessing the state of the two banks.*/
RET_ON_ERROR(mfs_bank_get_state(mfsp, MFS_BANK_0, &sts0, &cnt0));
RET_ON_ERROR(mfs_bank_get_state(mfsp, MFS_BANK_1, &sts1, &cnt1));
/* Handling all possible scenarios, each one requires its own recovery
strategy.*/
switch (PAIR(sts0, sts1)) {
case PAIR(MFS_BANK_ERASED, MFS_BANK_ERASED):
/* Both banks erased, first initialization.*/
RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, 1));
bank = MFS_BANK_0;
break;
case PAIR(MFS_BANK_OK, MFS_BANK_OK):
/* Both banks appear to be valid but one must be newer, erasing the
older one.*/
if (cnt0 > cnt1) {
/* Bank 0 is newer.*/
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
bank = MFS_BANK_0;
}
else {
/* Bank 1 is newer.*/
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
bank = MFS_BANK_1;
}
w1 = true;
break;
case PAIR(MFS_BANK_GARBAGE, MFS_BANK_GARBAGE):
/* Both banks are unreadable, reinitializing.*/
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, 1));
bank = MFS_BANK_0;
w1 = true;
break;
case PAIR(MFS_BANK_ERASED, MFS_BANK_OK):
/* Normal situation, bank one is used.*/
bank = MFS_BANK_1;
break;
case PAIR(MFS_BANK_OK, MFS_BANK_ERASED):
/* Normal situation, bank zero is used.*/
bank = MFS_BANK_0;
break;
case PAIR(MFS_BANK_ERASED, MFS_BANK_GARBAGE):
/* Bank zero is erased, bank one is not readable.*/
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, 1));
bank = MFS_BANK_0;
w1 = true;
break;
case PAIR(MFS_BANK_GARBAGE, MFS_BANK_ERASED):
/* Bank zero is not readable, bank one is erased.*/
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_1, 1));
bank = MFS_BANK_1;
w1 = true;
break;
case PAIR(MFS_BANK_OK, MFS_BANK_GARBAGE):
/* Bank zero is normal, bank one is unreadable.*/
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
bank = MFS_BANK_0;
w1 = true;
break;
case PAIR(MFS_BANK_GARBAGE, MFS_BANK_OK):
/* Bank zero is unreadable, bank one is normal.*/
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
bank = MFS_BANK_1;
w1 = true;
break;
default:
return MFS_ERR_INTERNAL;
}
/* Mounting the bank.*/
{
unsigned i;
/* Reading the bank header again.*/
RET_ON_ERROR(mfs_flash_read(mfsp, mfs_flash_get_bank_offset(mfsp, bank),
sizeof (mfs_bank_header_t),
mfsp->buffer.data8));
/* Checked again for extra safety.*/
if (mfs_bank_check_header(mfsp) != MFS_BANK_OK) {
return MFS_ERR_INTERNAL;
}
/* Storing the bank data.*/
mfsp->current_bank = bank;
mfsp->current_counter = mfsp->buffer.bhdr.fields.counter;
/* Scanning for the most recent instance of all records.*/
RET_ON_ERROR(mfs_bank_scan_records(mfsp, bank, &w2));
/* Calculating the effective used size.*/
mfsp->used_space = ALIGNED_SIZEOF(mfs_bank_header_t);
for (i = 0; i < MFS_CFG_MAX_RECORDS; i++) {
if (mfsp->descriptors[i].offset != 0U) {
mfsp->used_space += ALIGNED_REC_SIZE(mfsp->descriptors[i].size);
}
}
}
/* In case of detected problems then a garbage collection is performed in
order to repair/remove anomalies.*/
if (w2) {
RET_ON_ERROR(mfs_garbage_collect(mfsp));
}
return (w1 || w2) ? MFS_WARN_REPAIR : MFS_NO_ERROR;
}
/**
* @brief Configures and activates a MFS driver.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_WARN_GC if the operation triggered a garbage
* collection.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfs_mount(MFSDriver *mfsp) {
unsigned i;
/* Resetting previous state.*/
mfs_state_reset(mfsp);
/* Attempting to mount the managed partition.*/
for (i = 0; i < MFS_CFG_MAX_REPAIR_ATTEMPTS; i++) {
mfs_error_t err;
err = mfs_try_mount(mfsp);
if (err == MFS_ERR_INTERNAL) {
/* Special case, do not retry on internal errors but report
immediately.*/
mfsp->state = MFS_ERROR;
return err;
}
if (!MFS_IS_ERROR(err)) {
mfsp->state = MFS_READY;
return err;
}
}
/* Driver start failed.*/
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Initializes an instance.
*
* @param[out] mfsp pointer to the @p MFSDriver object
*
* @init
*/
void mfsObjectInit(MFSDriver *mfsp) {
osalDbgCheck(mfsp != NULL);
mfsp->state = MFS_STOP;
mfsp->config = NULL;
}
/**
* @brief Configures and activates a MFS driver.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] config pointer to the configuration
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been
* completed.
* @retval MFS_WARN_GC if the operation triggered a garbage
* collection.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsStart(MFSDriver *mfsp, const MFSConfig *config) {
osalDbgCheck((mfsp != NULL) && (config != NULL));
osalDbgAssert((mfsp->state == MFS_STOP) || (mfsp->state == MFS_READY) ||
(mfsp->state == MFS_ERROR), "invalid state");
/* Storing configuration.*/
mfsp->config = config;
return mfs_mount(mfsp);
}
/**
* @brief Deactivates a MFS driver.
*
* @param[in] mfsp pointer to the @p MFSDriver object
*
* @api
*/
void mfsStop(MFSDriver *mfsp) {
osalDbgCheck(mfsp != NULL);
osalDbgAssert((mfsp->state == MFS_STOP) || (mfsp->state == MFS_READY) ||
(mfsp->state == MFS_ERROR), "invalid state");
mfsp->config = NULL;
mfsp->state = MFS_STOP;
}
/**
* @brief Destroys the state of the managed storage by erasing the flash.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @return The operation status.
* @retval MFS_ERR_INV_STATE if the driver is in not in @p MFS_READY
* state.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsErase(MFSDriver *mfsp) {
osalDbgCheck(mfsp != NULL);
if (mfsp->state != MFS_READY) {
return MFS_ERR_INV_STATE;
}
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
return mfs_mount(mfsp);
}
/**
* @brief Retrieves and reads a data record.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] id record numeric identifier, the valid range is between
* @p 1 and @p MFS_CFG_MAX_RECORDS
* @param[in,out] np on input is the maximum buffer size, on return it is
* the size of the data copied into the buffer
* @param[out] buffer pointer to a buffer for record data
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_ERR_INV_STATE if the driver is in not in @p MFS_READY
* state.
* @retval MFS_ERR_INV_SIZE if the passed buffer is not large enough to
* contain the record data.
* @retval MFS_ERR_NOT_FOUND if the specified id does not exists.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsReadRecord(MFSDriver *mfsp, mfs_id_t id,
size_t *np, uint8_t *buffer) {
uint16_t crc;
osalDbgCheck((mfsp != NULL) &&
(id >= 1U) && (id <= (mfs_id_t)MFS_CFG_MAX_RECORDS) &&
(np != NULL) && (*np > 0U) && (buffer != NULL));
if ((mfsp->state != MFS_READY) && (mfsp->state != MFS_TRANSACTION)) {
return MFS_ERR_INV_STATE;
}
/* Checking if the requested record actually exists.*/
if (mfsp->descriptors[id - 1U].offset == 0U) {
return MFS_ERR_NOT_FOUND;
}
/* Making sure to not overflow the buffer.*/
if (*np < mfsp->descriptors[id - 1U].size) {
return MFS_ERR_INV_SIZE;
}
/* Header read from flash.*/
RET_ON_ERROR(mfs_flash_read(mfsp,
mfsp->descriptors[id - 1U].offset,
sizeof (mfs_data_header_t),
mfsp->buffer.data8));
/* Data read from flash.*/
*np = mfsp->descriptors[id - 1U].size;
RET_ON_ERROR(mfs_flash_read(mfsp,
mfsp->descriptors[id - 1U].offset + sizeof (mfs_data_header_t),
*np,
buffer));
/* Checking CRC.*/
crc = crc16(0xFFFFU, buffer, *np);
if (crc != mfsp->buffer.dhdr.fields.crc) {
mfsp->state = MFS_ERROR;
return MFS_ERR_FLASH_FAILURE;
}
return MFS_NO_ERROR;
}
/**
* @brief Creates or updates a data record.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] id record numeric identifier, the valid range is between
* @p 1 and @p MFS_CFG_MAX_RECORDS
* @param[in] n size of data to be written, it cannot be zero
* @param[in] buffer pointer to a buffer for record data
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_WARN_GC if the operation triggered a garbage
* collection.
* @retval MFS_ERR_INV_STATE if the driver is in not in @p MFS_READY
* state.
* @retval MFS_ERR_OUT_OF_MEM if there is not enough flash space for the
* operation.
* @retval MFS_ERR_TRANSACTION_NUM if the transaction operations buffer space
* has been exceeded.
* @retval MFS_ERR_TRANSACTION_SIZE if the transaction allocated space
* has been exceeded.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsWriteRecord(MFSDriver *mfsp, mfs_id_t id,
size_t n, const uint8_t *buffer) {
flash_offset_t free, asize, rspace;
osalDbgCheck((mfsp != NULL) &&
(id >= 1U) && (id <= (mfs_id_t)MFS_CFG_MAX_RECORDS) &&
(n > 0U) && (buffer != NULL));
/* Aligned record size.*/
asize = ALIGNED_REC_SIZE(n);
/* Normal mode code path.*/
if (mfsp->state == MFS_READY) {
bool warning = false;
/* If the required space is beyond the available (compacted) block
size then an error is returned.
NOTE: The space for one extra header is reserved in order to allow
for an erase operation after the space has been fully allocated.*/
rspace = ALIGNED_DHDR_SIZE + asize;
if (rspace > mfsp->config->bank_size - mfsp->used_space) {
return MFS_ERR_OUT_OF_MEM;
}
/* Checking for immediately (not compacted) available space.*/
free = (mfs_flash_get_bank_offset(mfsp, mfsp->current_bank) +
mfsp->config->bank_size) - mfsp->next_offset;
if (rspace > free) {
/* We need to perform a garbage collection, there is enough space
but it has to be freed.*/
warning = true;
RET_ON_ERROR(mfs_garbage_collect(mfsp));
}
/* Writing the data header without the magic, it will be written last.*/
mfsp->buffer.dhdr.fields.id = (uint16_t)id;
mfsp->buffer.dhdr.fields.size = (uint32_t)n;
mfsp->buffer.dhdr.fields.crc = crc16(0xFFFFU, buffer, n);
RET_ON_ERROR(mfs_flash_write(mfsp,
mfsp->next_offset + (sizeof (uint32_t) * 2U),
sizeof (mfs_data_header_t) - (sizeof (uint32_t) * 2U),
mfsp->buffer.data8 + (sizeof (uint32_t) * 2U)));
/* Writing the data part.*/
RET_ON_ERROR(mfs_flash_write(mfsp,
mfsp->next_offset + sizeof (mfs_data_header_t),
n,
buffer));
/* Finally writing the magic number, it seals the operation.*/
mfsp->buffer.dhdr.fields.magic1 = (uint32_t)MFS_HEADER_MAGIC_1;
mfsp->buffer.dhdr.fields.magic2 = (uint32_t)MFS_HEADER_MAGIC_2;
RET_ON_ERROR(mfs_flash_write(mfsp,
mfsp->next_offset,
sizeof (uint32_t) * 2U,
mfsp->buffer.data8));
/* The size of the old record instance, if present, must be subtracted
to the total used size.*/
if (mfsp->descriptors[id - 1U].offset != 0U) {
mfsp->used_space -= ALIGNED_REC_SIZE(mfsp->descriptors[id - 1U].size);
}
/* Adjusting bank-related metadata.*/
mfsp->descriptors[id - 1U].offset = mfsp->next_offset;
mfsp->descriptors[id - 1U].size = (uint32_t)n;
mfsp->next_offset += asize;
mfsp->used_space += asize;
return warning ? MFS_WARN_GC : MFS_NO_ERROR;
}
#if MFS_CFG_TRANSACTION_MAX > 0
/* Transaction mode code path.*/
if (mfsp->state == MFS_TRANSACTION) {
mfs_transaction_op_t *top;
/* Checking if the maximum number of operations in a transaction is
Exceeded.*/
if (mfsp->tr_nops >= MFS_CFG_TRANSACTION_MAX) {
return MFS_ERR_TRANSACTION_NUM;
}
/* If the required space is greater than the space allocated for the
transaction then error.*/
rspace = asize;
if (rspace > mfsp->tr_limit_offet - mfsp->tr_next_offset) {
return MFS_ERR_TRANSACTION_SIZE;
}
/* Writing the data header without the magic, it will be written last.*/
mfsp->buffer.dhdr.fields.id = (uint16_t)id;
mfsp->buffer.dhdr.fields.size = (uint32_t)n;
mfsp->buffer.dhdr.fields.crc = crc16(0xFFFFU, buffer, n);
RET_ON_ERROR(mfs_flash_write(mfsp,
mfsp->tr_next_offset + (sizeof (uint32_t) * 2U),
sizeof (mfs_data_header_t) - (sizeof (uint32_t) * 2U),
mfsp->buffer.data8 + (sizeof (uint32_t) * 2U)));
/* Writing the data part.*/
RET_ON_ERROR(mfs_flash_write(mfsp,
mfsp->tr_next_offset + sizeof (mfs_data_header_t),
n,
buffer));
/* Adding a transaction operation record.*/
top = &mfsp->tr_ops[mfsp->tr_nops];
top->offset = mfsp->tr_next_offset;
top->size = n;
top->id = id;
/* Number of records and next write position updated.*/
mfsp->tr_nops++;
mfsp->tr_next_offset += asize;
return MFS_NO_ERROR;
}
#endif /* MFS_CFG_TRANSACTION_MAX > 0 */
/* Invalid state.*/
return MFS_ERR_INV_STATE;
}
/**
* @brief Erases a data record.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] id record numeric identifier, the valid range is between
* @p 1 and @p MFS_CFG_MAX_RECORDS
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_WARN_GC if the operation triggered a garbage
* collection.
* @retval MFS_ERR_INV_STATE if the driver is in not in @p MFS_READY
* state.
* @retval MFS_ERR_OUT_OF_MEM if there is not enough flash space for the
* operation.
* @retval MFS_ERR_TRANSACTION_NUM if the transaction operations buffer space
* has been exceeded.
* @retval MFS_ERR_TRANSACTION_SIZE if the transaction allocated space
* has been exceeded.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsEraseRecord(MFSDriver *mfsp, mfs_id_t id) {
flash_offset_t free, asize, rspace;
osalDbgCheck((mfsp != NULL) &&
(id >= 1U) && (id <= (mfs_id_t)MFS_CFG_MAX_RECORDS));
/* Aligned record size.*/
asize = ALIGNED_DHDR_SIZE;
/* Normal mode code path.*/
if (mfsp->state == MFS_READY) {
bool warning = false;
/* Checking if the requested record actually exists.*/
if (mfsp->descriptors[id - 1U].offset == 0U) {
return MFS_ERR_NOT_FOUND;
}
/* If the required space is beyond the available (compacted) block
size then an internal error is returned, it should never happen.*/
rspace = asize;
if (rspace > mfsp->config->bank_size - mfsp->used_space) {
return MFS_ERR_INTERNAL;
}
/* Checking for immediately (not compacted) available space.*/
free = (mfs_flash_get_bank_offset(mfsp, mfsp->current_bank) +
mfsp->config->bank_size) - mfsp->next_offset;
if (rspace > free) {
/* We need to perform a garbage collection, there is enough space
but it has to be freed.*/
warning = true;
RET_ON_ERROR(mfs_garbage_collect(mfsp));
}
/* Writing the data header with size set to zero, it means that the
record is logically erased.*/
mfsp->buffer.dhdr.fields.magic1 = (uint32_t)MFS_HEADER_MAGIC_1;
mfsp->buffer.dhdr.fields.magic2 = (uint32_t)MFS_HEADER_MAGIC_2;
mfsp->buffer.dhdr.fields.id = (uint16_t)id;
mfsp->buffer.dhdr.fields.size = (uint32_t)0;
mfsp->buffer.dhdr.fields.crc = (uint16_t)0xFFFF;
RET_ON_ERROR(mfs_flash_write(mfsp,
mfsp->next_offset,
sizeof (mfs_data_header_t),
mfsp->buffer.data8));
/* Adjusting bank-related metadata.*/
mfsp->used_space -= ALIGNED_REC_SIZE(mfsp->descriptors[id - 1U].size);
mfsp->next_offset += sizeof (mfs_data_header_t);
mfsp->descriptors[id - 1U].offset = 0U;
mfsp->descriptors[id - 1U].size = 0U;
return warning ? MFS_WARN_GC : MFS_NO_ERROR;
}
#if MFS_CFG_TRANSACTION_MAX > 0
/* Transaction mode code path.*/
if (mfsp->state == MFS_TRANSACTION) {
mfs_transaction_op_t *top;
/* Checking if the requested record actually exists.*/
if (mfsp->descriptors[id - 1U].offset == 0U) {
return MFS_ERR_NOT_FOUND;
}
/* Checking if the maximum number of operations in a transaction is
Exceeded.*/
if (mfsp->tr_nops >= MFS_CFG_TRANSACTION_MAX) {
return MFS_ERR_TRANSACTION_NUM;
}
/* If the required space is greater than the space allocated for the
transaction then error.*/
rspace = asize;
if (rspace > mfsp->tr_limit_offet - mfsp->tr_next_offset) {
return MFS_ERR_TRANSACTION_SIZE;
}
/* Writing the data header with size set to zero, it means that the
record is logically erased. Note, the magic number is not set.*/
mfsp->buffer.dhdr.fields.id = (uint16_t)id;
mfsp->buffer.dhdr.fields.size = (uint32_t)0;
mfsp->buffer.dhdr.fields.crc = (uint16_t)0xFFFF;
RET_ON_ERROR(mfs_flash_write(mfsp,
mfsp->tr_next_offset + (sizeof (uint32_t) * 2U),
sizeof (mfs_data_header_t) - (sizeof (uint32_t) * 2U),
mfsp->buffer.data8 + (sizeof (uint32_t) * 2U)));
/* Adding a transaction operation record.*/
top = &mfsp->tr_ops[mfsp->tr_nops];
top->offset = mfsp->tr_next_offset;
top->size = 0U;
top->id = id;
/* Number of records and next write position updated.*/
mfsp->tr_nops++;
mfsp->tr_next_offset += asize;
return MFS_NO_ERROR;
}
#endif /* MFS_CFG_TRANSACTION_MAX > 0 */
return MFS_ERR_INV_STATE;
}
/**
* @brief Enforces a garbage collection operation.
* @details Garbage collection involves: integrity check, optionally repairs,
* obsolete data removal, data compaction and a flash bank swap.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_ERR_INV_STATE if the driver is in not in @p MFS_READY
* state.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsPerformGarbageCollection(MFSDriver *mfsp) {
osalDbgCheck(mfsp != NULL);
if (mfsp->state != MFS_READY) {
return MFS_ERR_INV_STATE;
}
return mfs_garbage_collect(mfsp);
}
#if (MFS_CFG_TRANSACTION_MAX > 0) || defined(__DOXYGEN__)
/**
* @brief Puts the driver in transaction mode.
* @note The parameters @p n and @p size are used to make an
* estimation of the space required for the transaction to succeed.
* Note that the estimated size must include also the extra space
* required by alignment enforcement option. If the estimated size
* is wrong (by defect) what could happen is that there is a failure
* in the middle of a transaction and a roll-back would be required.
* @note The conditions for starting a transaction are:
* - The driver must be started.
* - There must be enough compacted storage to accommodate the whole
* transaction. If the required space is available but it is not
* compacted then a garbage collect operation is performed.
* .
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @param[in] size estimated total size of written records in transaction,
* this includes, data, headers and alignment gaps
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_ERR_INV_STATE if the driver is in not in @p MFS_READY
* state.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsStartTransaction(MFSDriver *mfsp, size_t size) {
flash_offset_t free, tspace, rspace;
osalDbgCheck((mfsp != NULL) && (size > ALIGNED_DHDR_SIZE));
/* The driver must be in ready mode.*/
if (mfsp->state != MFS_READY) {
return MFS_ERR_INV_STATE;
}
/* Estimating the required contiguous compacted space.*/
tspace = (flash_offset_t)MFS_ALIGN_NEXT(size);
rspace = tspace + ALIGNED_DHDR_SIZE;
/* If the required space is beyond the available (compacted) block
size then an error is returned.*/
if (rspace > mfsp->config->bank_size - mfsp->used_space) {
return MFS_ERR_OUT_OF_MEM;
}
/* Checking for immediately (not compacted) available space.*/
free = (mfs_flash_get_bank_offset(mfsp, mfsp->current_bank) +
mfsp->config->bank_size) - mfsp->next_offset;
if (rspace > free) {
/* We need to perform a garbage collection, there is enough space
but it has to be freed.*/
RET_ON_ERROR(mfs_garbage_collect(mfsp));
}
/* Entering transaction mode.*/
mfsp->state = MFS_TRANSACTION;
/* Initializing transaction state.*/
mfsp->tr_next_offset = mfsp->next_offset;
mfsp->tr_nops = 0U;
mfsp->tr_limit_offet = mfsp->tr_next_offset + tspace;
return MFS_NO_ERROR;
}
/**
* @brief A transaction is committed and finalized atomically.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_ERR_INV_STATE if the driver is in not in @p MFS_TRANSACTION
* state.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsCommitTransaction(MFSDriver *mfsp) {
mfs_transaction_op_t *top;
osalDbgCheck(mfsp != NULL);
/* The driver must be in transaction mode.*/
if (mfsp->state != MFS_TRANSACTION) {
return MFS_ERR_INV_STATE;
}
/* Scanning all buffered operations in reverse order.*/
mfsp->buffer.dhdr.fields.magic1 = (uint32_t)MFS_HEADER_MAGIC_1;
mfsp->buffer.dhdr.fields.magic2 = (uint32_t)MFS_HEADER_MAGIC_2;
top = &mfsp->tr_ops[mfsp->tr_nops];
while (top > &mfsp->tr_ops[0]) {
/* On the previous element.*/
top--;
/* Finalizing the operation by writing the magic number.*/
RET_ON_ERROR(mfs_flash_write(mfsp,
top->offset,
sizeof (uint32_t) * 2U,
mfsp->buffer.data8));
}
/* Transaction fully committed by writing the last (first in transaction)
magic number, now updating the internal state using the buffered data.*/
mfsp->next_offset = mfsp->tr_next_offset;
while (top < &mfsp->tr_ops[mfsp->tr_nops]) {
unsigned i = (unsigned)top->id - 1U;
/* The calculation is a bit different depending on write or erase record
operations.*/
if (top->size > 0U) {
/* It is a write.*/
if (mfsp->descriptors[i].offset != 0U) {
/* The size of the old record instance, if present, must be subtracted
to the total used size.*/
mfsp->used_space -= ALIGNED_REC_SIZE(mfsp->descriptors[i].size);
}
/* Adjusting bank-related metadata.*/
mfsp->used_space += ALIGNED_REC_SIZE(top->size);
mfsp->descriptors[i].offset = top->offset;
mfsp->descriptors[i].size = top->size;
}
else {
/* It is an erase.*/
mfsp->used_space -= ALIGNED_REC_SIZE(mfsp->descriptors[i].size);
mfsp->descriptors[i].offset = 0U;
mfsp->descriptors[i].size = 0U;
}
/* On the next element.*/
top++;
}
/* Returning to ready mode.*/
mfsp->state = MFS_READY;
return MFS_NO_ERROR;
}
/**
* @brief A transaction is rolled back atomically.
* @details This function performs a garbage collection in order to discard
* all written data that has not been finalized.
*
* @param[in] mfsp pointer to the @p MFSDriver object
* @return The operation status.
* @retval MFS_NO_ERROR if the operation has been successfully
* completed.
* @retval MFS_ERR_INV_STATE if the driver is in not in @p MFS_TRANSACTION
* state.
* @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
* failures. Makes the driver enter the
* @p MFS_ERROR state.
* @retval MFS_ERR_INTERNAL if an internal logic failure is detected.
*
* @api
*/
mfs_error_t mfsRollbackTransaction(MFSDriver *mfsp) {
mfs_error_t err;
osalDbgCheck(mfsp != NULL);
if (mfsp->state != MFS_TRANSACTION) {
return MFS_ERR_INV_STATE;
}
/* Returning to ready mode.*/
mfsp->state = MFS_READY;
/* If no operations have been performed then there is no need to perform
a garbage collection.*/
if (mfsp->tr_nops > 0U) {
err = mfs_garbage_collect(mfsp);
}
else {
err = MFS_NO_ERROR;
}
return err;
}
#endif /* MFS_CFG_TRANSACTION_MAX > 0 */
/** @} */