X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=fs%2Fbattfs.c;h=93a8868e868b66e5b3950dddaf78f5382b996436;hb=HEAD;hp=ab8075f5146b430cd4ee759ec159754ab80f2bff;hpb=be167f67c180ba7de62fc50bcaeeb3920e05997c;p=bertos.git diff --git a/fs/battfs.c b/fs/battfs.c deleted file mode 100644 index ab8075f5..00000000 --- a/fs/battfs.c +++ /dev/null @@ -1,399 +0,0 @@ -/** - * \file - * - * - * \version $Id:$ - * - * \author Francesco Sacchi - * - * \brief BattFS: a filesystem for embedded platforms (implementation). - */ - -#include "battfs.h" - -#include -#include /* MIN, MAX */ -#include /* cpu_to_xx */ - - -#include /* memset, memmove */ - -/** - * Convert mark_t from cpu endianess to filesystem endianness. - * \note filesystem is in little-endian format. - */ -INLINE mark_t cpu_to_mark_t(mark_t mark) -{ - STATIC_ASSERT(sizeof(mark_t) == 2); - return cpu_to_le16(mark); -} - -/** - * Convert mark_t from filesystem endianness to cpu endianess. - * \note filesystem is in little-endian format. - */ -INLINE mark_t mark_t_to_cpu(mark_t mark) -{ - STATIC_ASSERT(sizeof(mark_t) == 2); - return le16_to_cpu(mark); -} - -/** - * Convert from cpu endianess to filesystem endianness. - * \note filesystem is in little-endian format. - */ -INLINE void cpu_to_battfs(struct BattFsPageHeader *hdr) -{ - STATIC_ASSERT(sizeof(hdr->inode) == 1); - STATIC_ASSERT(sizeof(hdr->seq) == 1); - - hdr->mark = cpu_to_mark_t(hdr->mark); - - STATIC_ASSERT(sizeof(hdr->fill) == 2); - hdr->fill = cpu_to_le16(hdr->fill); - - STATIC_ASSERT(sizeof(hdr->pgoff) == 2); - hdr->pgoff = cpu_to_le16(hdr->pgoff); - - STATIC_ASSERT(sizeof(hdr->fcs) == 2); - hdr->fcs = cpu_to_le16(hdr->fcs); - - STATIC_ASSERT(sizeof(hdr->rfu) == 2); - hdr->rfu = cpu_to_le16(hdr->rfu); -} - - -/** - * Convert from filesystem endianness to cpu endianess. - * \note filesystem is in little-endian format. - */ -INLINE void battfs_to_cpu(struct BattFsPageHeader *hdr) -{ - STATIC_ASSERT(sizeof(hdr->inode) == 1); - STATIC_ASSERT(sizeof(hdr->seq) == 1); - - hdr->mark = mark_t_to_cpu(hdr->mark); - - STATIC_ASSERT(sizeof(hdr->fill) == 2); - hdr->fill = le16_to_cpu(hdr->fill); - - STATIC_ASSERT(sizeof(hdr->pgoff) == 2); - hdr->pgoff = le16_to_cpu(hdr->pgoff); - - STATIC_ASSERT(sizeof(hdr->fcs) == 2); - hdr->fcs = le16_to_cpu(hdr->fcs); - - STATIC_ASSERT(sizeof(hdr->rfu) == 2); - hdr->rfu = le16_to_cpu(hdr->rfu); -} - - -/** - * Read header of page \a page. - * \return true on success, false otherwise. - * \note \a hdr is dirtyed even on errors. - */ -static bool battfs_readHeader(struct BattFsSuper *disk, pgcnt_t page, struct BattFsPageHeader *hdr) -{ - /* - * Read header from disk. - * header is actually a footer, and so - * resides at page end. - */ - if (disk->read(disk, page, disk->page_size - sizeof(BattFsPageHeader), hdr, sizeof(BattFsPageHeader)) - != sizeof(BattFsPageHeader)) - { - TRACEMSG("Error: page[%d]\n", page); - return false; - } - - /* Fix endianess */ - battfs_to_cpu(hdr); - - return true; -} - -/** - * Count the number of pages from - * inode 0 to \a inode in \a filelen_table. - */ -static pgcnt_t countPages(pgoff_t *filelen_table, inode_t inode) -{ - pgcnt_t cnt = 0; - - for (inode_t i = 0; i < inode; i++) - cnt += filelen_table[i]; - - return cnt; -} - -/** - * Move all pages in page allocation array from \a src to \a src + \a offset. - * The number of pages moved is page_count - MAX(dst, src). - */ -static void movePages(struct BattFsSuper *disk, pgcnt_t src, int offset) -{ - pgcnt_t dst = src + offset; - memmove(&disk->page_array[dst], &disk->page_array[src], disk->page_count - MAX(dst, src) * sizeof(pgcnt_t)); - - if (offset < 0) - { - /* Fill empty space in array with sentinel */ - for (pgcnt_t page = disk->page_count + offset; page < disk->page_count; page++) - disk->page_array[page] = PAGE_UNSET_SENTINEL; - } -} - -/** - * Insert \a page into page allocation array of \a disk, using \a filelen_table and - * \a free_number to compute position. - */ -static void insertFreePage(struct BattFsSuper *disk, pgoff_t *filelen_table, mark_t free_number, pgcnt_t page) -{ - ASSERT(mark >= disk->min_free); - ASSERT(mark <= disk->max_free); - - pgcnt_t free_pos = countPages(filelen_table, BATTFS_MAX_FILES - 1); - free_pos += free_number - disk->min_free; - ASSERT(disk->page_array[free_pos] == PAGE_UNSET_SENTINEL); - disk->page_array[free_pos] = page; -} - -/** - * Mark \a page of \a disk as free. - * \note max_free of \a disk is increased by 1 and is used as - * \a page free marker. - */ -static bool battfs_markFree(struct BattFsSuper *disk, pgcnt_t page) -{ - pgaddr_t addr = disk->page_size - sizeof(BattFsPageHeader) + offsetof(BattFsPageHeader, mark); - mark_t mark = cpu_to_mark_t(++disk->max_free); - if (!disk->write(disk, page, addr, &mark, sizeof(mark))) - { - TRACEMSG("error marking page [%d]\n", page); - return false; - } - else - return true; -} - - -/** - * Initialize and mount disk described by - * \a d. - * \return false on errors, true otherwise. - */ -bool battfs_init(struct BattFsSuper *disk) -{ - BattFsPageHeader hdr; - rotating_t cks; - pgoff_t filelen_table[BATTFS_MAX_FILES]; - - /* Sanity checks */ - ASSERT(disk->open); - ASSERT(disk->read); - ASSERT(disk->write); - ASSERT(disk->erase); - ASSERT(disk->close); - ASSERT(disk->page_size); - ASSERT(disk->page_count); - ASSERT(disk->page_count < PAGE_UNSET_SENTINEL - 1); - ASSERT(disk->page_array); - - /* Init disk device */ - if (!disk->open(disk)) - { - TRACEMSG("open error\n"); - return false; - } - - memset(filelen_table, 0, BATTFS_MAX_FILES * sizeof(pgoff_t)); - - /* Initialize min free sequence number to max value */ - disk->min_free = MARK_PAGE_VALID; - /* Initialize max free sequence number to min value */ - disk->max_free = 0; - - disk->free_bytes = 0; - disk->disk_size = (disk_size_t)(disk->page_size - sizeof(BattFsPageHeader)) * disk->page_count; - - /* Count the number of disk page per files */ - for (pgcnt_t page = 0; page < disk->page_count; page++) - { - if (!battfs_readHeader(disk, page, &hdr)) - return false; - - /* Check header FCS */ - rotating_init(&cks); - rotating_update(&hdr, sizeof(BattFsPageHeader) - sizeof(rotating_t), &cks); - if (cks == hdr.fcs) - { - /* Page is valid and is owned by a file */ - filelen_table[hdr.inode]++; - - ASSERT(hdr.mark == MARK_PAGE_VALID); - ASSERT(hdr.fill <= disk->page_size - sizeof(BattFsPageHeader)); - /* Keep trace of free space */ - disk->free_bytes += disk->page_size - sizeof(BattFsPageHeader) - hdr.fill; - } - else - { - /* Increase free space */ - disk->free_bytes += disk->page_size - sizeof(BattFsPageHeader); - - /* Check if setting mark to MARK_PAGE_VALID makes fcs correct */ - mark_t old_mark = hdr.mark; - hdr.mark = MARK_PAGE_VALID; - rotating_init(&cks); - rotating_update(&hdr, sizeof(BattFsPageHeader) - sizeof(rotating_t), &cks); - if (cks == hdr.fcs) - { - /* - * This page is a valid and marked free page. - * Update min and max free page sequence numbers. - */ - disk->min_free = MIN(disk->min_free, old_mark); - disk->max_free = MAX(disk->max_free, old_mark); - } - else - TRACEMSG("page [%d] invalid, keeping as free\n", page); - } - } - - /* Once here, we have filelen_table filled with file lengths */ - - /* Fill page array with sentinel */ - for (pgcnt_t page = 0; page < disk->page_count; page++) - disk->page_array[page] = PAGE_UNSET_SENTINEL; - - /* Fill page allocation array */ - for (pgcnt_t page = 0; page < disk->page_count; page++) - { - if (!battfs_readHeader(disk, page, &hdr)) - return false; - - /* Check header FCS */ - rotating_init(&cks); - rotating_update(&hdr, sizeof(BattFsPageHeader) - sizeof(rotating_t), &cks); - if (cks == hdr.fcs) - { - /* Page is valid and is owned by a file */ - ASSERT(hdr.mark == MARK_PAGE_VALID); - - /* Compute array position */ - pgcnt_t array_pos = countPages(filelen_table, hdr.inode); - array_pos += hdr.pgoff; - - /* Check if position is already used by another page of the same file */ - if (disk->page_array[array_pos] == PAGE_UNSET_SENTINEL) - disk->page_array[array_pos] = page; - else - { - BattFsPageHeader hdr_old; - - if (!battfs_readHeader(disk, disk->page_array[array_pos], &hdr_old)) - return false; - - #ifdef _DEBUG - /* Check header FCS */ - rotating_t cks_old; - rotating_init(&cks_old); - rotating_update(&hdr_old, sizeof(BattFsPageHeader) - sizeof(rotating_t), &cks_old); - ASSERT(cks_old == hdr_old.fcs); - #endif - - /* Only the very same page with a different seq number can be here */ - ASSERT(hdr.inode == hdr_old.inode); - ASSERT(hdr.pgoff == hdr_old.pgoff); - ASSERT(hdr.mark == hdr_old.mark); - ASSERT(hdr.seq != hdr_old.seq); - - pgcnt_t new_page, old_page; - fill_t old_fill; - - /* Fancy check to handle seq wraparound */ - #define HALF_SEQ (1 << ((sizeof(seq_t) * CPU_BITS_PER_CHAR) - 1)) - if ((hdr.seq - hdr_old.seq) < HALF_SEQ) - { - /* Actual header is newer than the previuos one */ - old_page = disk->page_array[array_pos]; - new_page = page; - old_fill = hdr_old.fill; - } - else - { - /* Previous header is newer than the current one */ - old_page = page; - new_page = disk->page_array[array_pos]; - old_fill = hdr.fill; - } - - /* Set new page */ - disk->page_array[array_pos] = new_page; - - /* Add free space */ - disk->free_bytes += old_fill; - - /* Shift all array one position to the left, overwriting duplicate page */ - array_pos -= hdr.pgoff; - array_pos += filelen_table[hdr.inode]; - movePages(disk, array_pos, -1); - - /* Decrease file page count */ - filelen_table[hdr.inode]--; - - /* Add old page to free pages pool */ - if (!battfs_markFree(disk, old_page)) - return false; - - insertFreePage(disk, filelen_table, disk->max_free, old_page); - } - } - else - { - /* Check if setting mark to MARK_PAGE_VALID makes fcs correct */ - mark_t mark = hdr.mark; - hdr.mark = MARK_PAGE_VALID; - rotating_init(&cks); - rotating_update(&hdr, sizeof(BattFsPageHeader) - sizeof(rotating_t), &cks); - if (cks != hdr.fcs) - /* Page is not a valid marked page, insert at the end of list */ - mark = ++disk->max_free; - - insertFreePage(disk, filelen_table, mark, page); - } - } - - #warning Test me! - return true; -} - -