* Header is actually a footer, and so
* resides at page end.
*/
- if (disk->write(disk, page, disk->page_size - BATTFS_HEADER_LEN, buf, BATTFS_HEADER_LEN)
- != BATTFS_HEADER_LEN)
+ if (!(disk->bufferWrite(disk, disk->page_size - BATTFS_HEADER_LEN, buf, BATTFS_HEADER_LEN)
+ == BATTFS_HEADER_LEN && disk->save(disk, page)))
{
LOG_ERR("Error: page[%d]\n", page);
return false;
* inside file.
* e.g. : at page array[0] you will find page address of the first page
* of the first file (if present).
- * Free blocks are allocated after the last file, starting from invalid ones
- * and continuing with the marked free ones.
+ * Free blocks are allocated after the last file.
*
* \return true if ok, false on disk read errors.
- * \note The whole disk is scanned once.
+ * \note The whole disk is scanned at max twice.
*/
static bool fillPageArray(struct BattFsSuper *disk, pgoff_t *filelen_table)
{
return true;
}
-#if 0
-/**
- * Find the latest version of a page, starting from the
- * page supplied by \a page_array.
- * The pages are read from the disk until a different
- * inode or page offset is found.
- * The lastest version of the page is moved in the first
- * position of \a page_array.
- * \return the number of old versions of the page or PAGE_ERROR
- * on disk read errors.
- */
-static pgcnt_t findLastVersion(struct BattFsSuper *disk, pgcnt_t *page_array)
-{
- pgcnt_t *array_start = page_array;
- BattFsPageHeader hdr;
- if (!battfs_readHeader(disk, *page_array++, &hdr))
- return PAGE_ERROR;
-
- /* Free space: early bailout */
- if (hdr.fcs != computeFcs(&hdr))
- return 0;
-
- /*
- * If the first page is valid,
- * inode and pg_off in the array are taken
- * as the current page markers.
- */
- inode_t curr_inode = hdr.inode;
- pgoff_t curr_pgoff = hdr.pgoff;
-
- /* Temps used to find the sequence number range */
- seq_t minl = HALF_SEQ - 1;
- seq_t maxl = 0;
- seq_t minh = MAX_SEQ;
- seq_t maxh = MAX_SEQ;
- pgcnt_t lpos = 0, hpos = 0, dup_cnt = 0;
-
- /*
- * Find min and max values for the two
- * half of seq_num range.
- * With this we can find seqnum wraparounds.
- * seq_t is a type that has at least 1 bit more than
- * pgaddr_t. So all version of a page blocks can be numbered using
- * at most half numbers of a seq_t type.
- * The sequence number algorithm increments by 1 the previous seq_num
- * every time a page is rewritten. So the sequence is
- * guaranteed to be countiguous.
- * Only wrap arounds may happen, but due to half size sequence limitation,
- * there are only 4 possible situations:
- *
- * \verbatim
- * |------lower half------|-------upper half-------|
- *
- * 1) |------minl*****maxl---|------------------------|
- * 2) |------minl********maxl|minh******maxh----------|
- * 3) |----------------------|----minh*******maxh-----|
- * 4) |minl******maxl--------|------------minh****maxh|
- * \endverbatim
- *
- * Situations 1 and 3 are easy to detect, while 2 and 4 require more care.
- */
- do
- {
- if (hdr.seq < HALF_SEQ)
- {
- minl = MIN(minl, hdr.seq);
- if (hdr.seq > maxl)
- {
- maxl = hdr.seq;
- lpos = dup_cnt;
- }
- }
- else
- {
- minh = MIN(minh, hdr.seq);
- if (hdr.seq > maxh)
- {
- maxh = hdr.seq;
- hpos = dup_cnt;
- }
- }
-
- if (!battfs_readHeader(disk, *page_array++, &hdr))
- return PAGE_ERROR;
- dup_cnt++;
- }
- while (curr_inode == hdr.inode && curr_pgoff == hdr.pgoff && hdr.fcs == computeFcs(&hdr));
-
-
- /* Return early if there is only one version of the current page */
- if (dup_cnt == 1)
- return 0;
-
- /* Find the position in the array of the last version of the page */
- pgcnt_t last_ver = hpos;
- if (maxl >= minl)
- {
- /* Valid interval found in lower half */
- if (maxh >= minh)
- {
- /* Valid interval also found in upper half */
- if (maxl != minh - 1)
- {
- /* Interval starts in upper half and ends in lower */
- ASSERT(minl == 0);
- ASSERT(maxh == MAX_SEQ);
-
- last_ver = lpos;
- }
- }
- else
- /*
- * Upper interval is invalid.
- * Use lower values.
- */
- last_ver = lpos;
- }
-
- /* Put last page version at array start position */
- SWAP(array_start[0], array_start[last_ver]);
-
- return dup_cnt - 1;
-}
/**
- * Collect old pages, removing empty spaces from \a pg_array, for a maximum len of \a pg_len.
- * Once the collect task is completed, copy \a old_cnt pages from \a old_pages at the
- * end of free space in pg_array.
+ * Flush the current \a disk buffer.
+ * \return true if ok, false on errors.
*/
-void collectOldPages(pgcnt_t *pg_array, pgcnt_t pg_len, pgcnt_t *old_pages, pgcnt_t old_cnt)
+static bool battfs_flushBuffer(struct BattFsSuper *disk)
{
- bool copy = false;
- pgcnt_t gap = 0;
-
- for (pgcnt_t curr_page = 0; curr_page < pg_len; curr_page++)
+ if (disk->cache_dirty)
{
- if (!copy)
- {
- if (pg_array[curr_page] == PAGE_UNSET_SENTINEL)
- gap++;
- else
- {
- pg_array[curr_page - gap] = pg_array[curr_page];
- copy = true;
- }
- }
- else
- {
- if (pg_array[curr_page] != PAGE_UNSET_SENTINEL)
- pg_array[curr_page - gap] = pg_array[curr_page];
- else
- {
- gap++;
- copy = false;
- }
- }
- }
- ASSERT(gap == old_cnt);
- pg_array += pg_len - old_cnt;
+ LOG_INFO("Flushing to disk page %d\n", disk->curr_page);
+ if (!disk->erase(disk, disk->curr_page))
+ return false;
- memcpy(pg_array, old_pages, old_cnt * sizeof(pgcnt_t));
+ if (!disk->save(disk, disk->curr_page))
+ return false;
+ disk->cache_dirty = false;
+ }
+ return true;
}
/**
- * This function scan the page array of \a disk looking for
- * old versions of the same page.
- *
- * Only the last version is kept as valid, the old ones are inserted
- * in the free blocks heap.
- * \return true if ok, false on disk read errors.
- * \note The whole disk is scanned once.
+ * Load \a new_page from \a disk in disk page buffer.
+ * If a previuos page is still dirty in the buffer, will be
+ * flushed first.
+ * \return true if ok, false on errors.
*/
-static bool dropOldPages(struct BattFsSuper *disk)
+static bool battfs_loadPage(struct BattFsSuper *disk, pgcnt_t new_page)
{
- #define OLD_PAGE_BUFLEN 64
- pgcnt_t old_pages[OLD_PAGE_BUFLEN];
- pgcnt_t old_cnt = 0;
-
- pgcnt_t *curr_page = disk->page_array;
- pgcnt_t *collect_start = disk->page_array;
- pgcnt_t collect_len = disk->page_count;
- pgcnt_t dup_pages;
-
- do
- {
- dup_pages = findLastVersion(disk, curr_page);
- if (dup_pages == PAGE_ERROR)
- return false;
- /* The first page is the last version */
- curr_page++;
- while (dup_pages--)
- {
- if (old_cnt >= OLD_PAGE_BUFLEN)
- {
- collectOldPages(collect_start, collect_len, old_pages, old_cnt);
- collect_len -= old_cnt;
- disk->free_bytes += old_cnt * (disk->page_size - BATTFS_HEADER_LEN);
- disk->free_page_start -= old_cnt;
- curr_page -= old_cnt;
- collect_start = curr_page;
- old_cnt = 0;
- }
+ LOG_INFO("Loading page %d\n", new_page);
+ if (disk->curr_page == new_page)
+ return true;
- old_pages[old_cnt++] = *curr_page;
- *curr_page++ = PAGE_UNSET_SENTINEL;
- }
- }
- while (curr_page < disk->page_array + disk->free_page_start);
+ if (!battfs_flushBuffer(disk))
+ return false;
- collectOldPages(collect_start, collect_len, old_pages, old_cnt);
- disk->free_bytes += old_cnt * (disk->page_size - BATTFS_HEADER_LEN);
- disk->free_page_start -= old_cnt;
+ if (!disk->load(disk, new_page))
+ return false;
+ disk->curr_page = new_page;
return true;
}
-#endif
+
/**
* Initialize and mount disk described by
/* Disk open must set all of these */
ASSERT(disk->read);
- ASSERT(disk->write);
+ ASSERT(disk->load);
+ ASSERT(disk->bufferWrite);
+ ASSERT(disk->save);
ASSERT(disk->erase);
ASSERT(disk->close);
ASSERT(disk->page_size);
LOG_ERR("error filling page array\n");
return false;
}
+ #warning TODO: shuffle free blocks
+
+ /* Initialize page buffer cache */
+ disk->cache_dirty = false;
+ disk->curr_page = 0;
+ disk->load(disk, disk->curr_page);
/* Init list for opened files. */
LIST_INIT(&disk->file_opened_list);
*/
static int battfs_flush(struct KFile *fd)
{
- (void)fd;
- #warning TODO
- return 0;
+ BattFs *fdb = BATTFS_CAST(fd);
+
+ if (battfs_flushBuffer(fdb->disk))
+ return 0;
+ else
+ return EOF;
}
/**
return 0;
}
+
+/**
+ * Write to file \a fd \a size bytes from \a buf.
+ * \return The number of bytes written.
+ */
+static size_t battfs_write(struct KFile *fd, const void *_buf, size_t size)
+{
+ BattFs *fdb = BATTFS_CAST(fd);
+ const uint8_t *buf = (const uint8_t *)_buf;
+
+ size_t total_write = 0;
+ pgoff_t pg_offset;
+ pgaddr_t addr_offset;
+ pgaddr_t wr_len;
+
+ size = MIN((kfile_off_t)size, fd->size - fd->seek_pos);
+
+ while (size)
+ {
+ #warning TODO: outside EOF?
+
+ pg_offset = fd->seek_pos / (fdb->disk->page_size - BATTFS_HEADER_LEN);
+ addr_offset = fd->seek_pos % (fdb->disk->page_size - BATTFS_HEADER_LEN);
+ wr_len = MIN(size, (size_t)(fdb->disk->page_size - BATTFS_HEADER_LEN - addr_offset));
+
+
+ if (fdb->start[pg_offset] != fdb->disk->curr_page)
+ {
+ if (!battfs_loadPage(fdb->disk, fdb->start[pg_offset]))
+ {
+ #warning TODO set error?
+ return total_write;
+ }
+
+ /* Get a free page */
+ fdb->disk->curr_page = fdb->disk->page_array[fdb->disk->free_page_start];
+ movePages(fdb->disk, fdb->disk->free_page_start + 1, -1);
+
+ /* Insert previous page in free blocks list */
+ fdb->disk->page_array[fdb->disk->page_count - 1] = fdb->start[pg_offset];
+ /* Assign new page */
+ fdb->start[pg_offset] = fdb->disk->curr_page;
+ #warning TODO: hdr have to be updated!
+ }
+
+
+ if (fdb->disk->bufferWrite(fdb->disk, addr_offset, buf, wr_len) != wr_len)
+ {
+ #warning TODO set error?
+ }
+ fdb->disk->cache_dirty = true;
+
+ size -= wr_len;
+ fd->seek_pos += wr_len;
+ total_write += wr_len;
+ buf += wr_len;
+ #warning TODO: hdr have to be updated!
+ }
+ return total_write;
+
+}
+
+
/**
* Read from file \a fd \a size bytes in \a buf.
* \return The number of bytes read.
addr_offset = fd->seek_pos % (fdb->disk->page_size - BATTFS_HEADER_LEN);
read_len = MIN(size, (size_t)(fdb->disk->page_size - BATTFS_HEADER_LEN - addr_offset));
+ /* Flush current page if needed */
+ if (fdb->start[pg_offset] == fdb->disk->curr_page)
+ battfs_flushBuffer(fdb->disk);
+
/* Read from disk */
if (fdb->disk->read(fdb->disk, fdb->start[pg_offset], addr_offset, buf, read_len) != read_len)
{
static pgcnt_t *findFile(BattFsSuper *disk, inode_t inode)
{
BattFsPageHeader hdr;
- pgcnt_t first = 0, page, last = disk->page_count -1;
+ pgcnt_t first = 0, page, last = disk->free_page_start;
fcs_t fcs;
- while (first <= last)
+ while (first < last)
{
page = (first + last) / 2;
* in disk->page_array. Size is written in \a size.
* \return true if all s ok, false on disk read errors.
*/
-static bool countFileSize(BattFsSuper *disk, pgcnt_t *start, inode_t inode, file_size_t *size)
+static file_size_t countFileSize(BattFsSuper *disk, pgcnt_t *start, inode_t inode)
{
- *size = 0;
+ file_size_t size = 0;
BattFsPageHeader hdr;
for (;;)
{
if (!battfs_readHeader(disk, *start++, &hdr))
- return false;
+ return EOF;
if (hdr.fcs == computeFcs(&hdr) && hdr.inode == inode)
- *size += hdr.fill;
+ size += hdr.fill;
else
- return true;
+ return size;
}
}
}
/* Fill file size */
- if (!countFileSize(disk, fd->start, inode, &fd->fd.size))
+ if ((fd->fd.size = countFileSize(disk, fd->start, inode)) == EOF)
return false;
/* Reset seek position */
fd->fd.read = battfs_read;
fd->fd.reopen = kfile_genericReopen;
fd->fd.seek = kfile_genericSeek;
+ fd->fd.write = battfs_write;
-#warning TODO battfs_write, battfs_error, battfs_clearerr
+#warning TODO battfs_error, battfs_clearerr
#if 0
- fd->fd.write = battfs_write;
fd->fd.error = battfs_error;
fd->fd.clearerr = battfs_clearerr;
#endif
return disk->close(disk) && (res == 0);
}
+#if UNIT_TEST
bool battfs_writeTestBlock(struct BattFsSuper *disk, pgcnt_t page, inode_t inode, seq_t seq, fill_t fill, pgoff_t pgoff)
{
BattFsPageHeader hdr;
+ /* Reset page to all 0xff */
+ uint8_t buf[disk->page_size];
+ memset(buf, 0xFF, disk->page_size);
+ disk->bufferWrite(disk, 0, buf, disk->page_size);
+
hdr.inode = inode;
hdr.fill = fill;
hdr.pgoff = pgoff;
return true;
}
+#endif
projects / bertos.git / blobdiff