X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=bertos%2Ffs%2Fbattfs.c;h=9bc8bdfd0b649b556743dcb1fae4b68eef509f6f;hb=c78bc5055c5fe1b424974f870abda1424166e5db;hp=aeacb9cd40b2cf294c1d9d90efc4142342eff32e;hpb=981ca46472cea3525828a899d83c9f3a1ed9c497;p=bertos.git

diff --git a/bertos/fs/battfs.c b/bertos/fs/battfs.c
index aeacb9cd..9bc8bdfd 100644
--- a/bertos/fs/battfs.c
+++ b/bertos/fs/battfs.c
@@ -44,9 +44,25 @@
 #include <cfg/macros.h> /* MIN, MAX */
 #include <cpu/byteorder.h> /* cpu_to_xx */
 
+#define LOG_LEVEL       LOG_LVL_INFO
+#define LOG_FORMAT      LOG_FMT_VERBOSE
+#include <cfg/log.h>
 
 #include <string.h> /* memset, memmove */
 
+#if LOG_LEVEL >= LOG_LVL_INFO
+static void dumpPageArray(struct BattFsSuper *disk)
+{
+	kprintf("Page array dump, free_page_start %d:", disk->free_page_start);
+	for (pgcnt_t i = 0; i < disk->page_count; i++)
+	{
+		if (!(i % 16))
+			kputchar('\n');
+		kprintf("%04d ", disk->page_array[i]);
+	}
+	kputchar('\n');
+}
+#endif
 
 /**
  * Convert from memory representation to disk structure.
@@ -64,25 +80,14 @@ INLINE void battfs_to_disk(struct BattFsPageHeader *hdr, uint8_t *buf)
 	buf[4] = hdr->pgoff >> 8;
 
 	/*
-	 * Mark is at least 1 bit longer than page address.
-	 * Needed to take care of wraparonds.
-	 */
-	buf[5] = hdr->mark;
-	buf[6] = hdr->mark >> 8;
-
-	/*
-	 * First bit used by mark, last 2 bits used by seq.
-	 * Since only 2 pages with the same inode and pgoff
-	 * can exist at the same time, 2 bit for seq are enough.
-	 * Unused bits are set to 1.
-	 */
-	buf[7] = ((hdr->mark >> 16) & 0x01) | (hdr->seq << 6) | ~(BV(7) | BV(6) | BV(0));
-
-	/*
-	 * This field must be the before the last one!
+	 * Sequence number is 40 bits long.
+	 * No need to take care of wraparonds: the memory will die first!
 	 */
-	buf[8] = hdr->fcs_free;
-	buf[9] = hdr->fcs_free >> 8;
+	buf[5] = hdr->seq;
+	buf[6] = hdr->seq >> 8;
+	buf[7] = hdr->seq >> 16;
+	buf[8] = hdr->seq >> 24;
+	buf[9] = hdr->seq >> 32;
 
 	/*
 	 * This field must be the last one!
@@ -103,9 +108,7 @@ INLINE void disk_to_battfs(uint8_t *buf, struct BattFsPageHeader *hdr)
 	hdr->inode = buf[0];
 	hdr->fill = buf[2] << 8 | buf[1];
 	hdr->pgoff = buf[4] << 8 | buf[3];
-	hdr->mark = (mark_t)(buf[7] & 0x01) << 16 | buf[6] << 8 | buf[5];
-	hdr->seq = buf[7] >> 6;
-	hdr->fcs_free = buf[9] << 8 | buf[8];
+	hdr->seq = (seq_t)buf[9] << 32 | (seq_t)buf[8] << 24 | (seq_t)buf[7] << 16 | buf[6] << 8 | buf[5];
 	hdr->fcs = buf[11] << 8 | buf[10];
 }
 
@@ -125,26 +128,26 @@ static fcs_t computeFcs(struct BattFsPageHeader *hdr)
 }
 
 /**
- * Compute the fcs of the header marked as free.
+ * Read from disk.
+ * If available, the cache will be used.
+ * \return the number of bytes read.
  */
-static fcs_t computeFcsFree(struct BattFsPageHeader *hdr)
+static size_t diskRead(struct BattFsSuper *disk, pgcnt_t page, pgaddr_t addr, void *buf, size_t size)
 {
-	uint8_t buf[BATTFS_HEADER_LEN];
-	fcs_t cks;
-
-	battfs_to_disk(hdr, buf);
-	rotating_init(&cks);
-	/* fcs_free is just before fcs of whole header */
-	rotating_update(buf, BATTFS_HEADER_LEN - 2 * sizeof(fcs_t), &cks);
-	return cks;
+	/* Try to read from cache */
+	if (page == disk->curr_page)
+		return disk->bufferRead(disk, addr, buf, size);
+	/* Read from disk */
+	else
+		return disk->read(disk, page, addr, buf, size);
 }
 
 
 /**
- * Read header of page \a page.
+ * Read header of \a page in \a hdr.
  * \return true on success, false otherwise.
  */
-static bool battfs_readHeader(struct BattFsSuper *disk, pgcnt_t page, struct BattFsPageHeader *hdr)
+static bool readHdr(struct BattFsSuper *disk, pgcnt_t page, struct BattFsPageHeader *hdr)
 {
 	uint8_t buf[BATTFS_HEADER_LEN];
 	/*
@@ -152,10 +155,10 @@ static bool battfs_readHeader(struct BattFsSuper *disk, pgcnt_t page, struct Bat
 	 * Header is actually a footer, and so
 	 * resides at page end.
 	 */
-	if (disk->read(disk, page, disk->page_size - BATTFS_HEADER_LEN, buf, BATTFS_HEADER_LEN)
+	if (diskRead(disk, page, disk->page_size - BATTFS_HEADER_LEN, buf, BATTFS_HEADER_LEN)
 	    != BATTFS_HEADER_LEN)
 	{
-		TRACEMSG("Error: page[%d]\n", page);
+		LOG_ERR("page[%d]\n", page);
 		return false;
 	}
 
@@ -166,27 +169,45 @@ static bool battfs_readHeader(struct BattFsSuper *disk, pgcnt_t page, struct Bat
 }
 
 /**
- * Write header of page \a page.
+ * Set header on current \a disk page buffer.
  * \return true on success, false otherwise.
  */
-static bool battfs_writeHeader(struct BattFsSuper *disk, pgcnt_t page, struct BattFsPageHeader *hdr)
+static bool setBufferHdr(struct BattFsSuper *disk, struct BattFsPageHeader *hdr)
 {
 	uint8_t buf[BATTFS_HEADER_LEN];
 
+	#warning FIXME:refactor computeFcs to save time and stack
+	hdr->fcs = computeFcs(hdr);
 	/* Fill buffer */
 	battfs_to_disk(hdr, buf);
 
 	/*
-	 * write header to disk.
+	 * write header to buffer.
 	 * 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)
+	if (disk->bufferWrite(disk, disk->page_size - BATTFS_HEADER_LEN, buf, BATTFS_HEADER_LEN)
+	    != BATTFS_HEADER_LEN)
+	{
+		LOG_ERR("writing to buffer\n");
+		return false;
+	}
+	return true;
+}
+
+static bool getBufferHdr(struct BattFsSuper *disk, struct BattFsPageHeader *hdr)
+{
+	uint8_t buf[BATTFS_HEADER_LEN];
+
+	if (disk->bufferRead(disk, disk->page_size - BATTFS_HEADER_LEN, buf, BATTFS_HEADER_LEN)
 	    != BATTFS_HEADER_LEN)
 	{
-		TRACEMSG("Error: page[%d]\n", page);
+		LOG_ERR("reading from buffer\n");
 		return false;
 	}
+
+	disk_to_battfs(buf, hdr);
+
 	return true;
 }
 
@@ -211,6 +232,7 @@ static pgcnt_t countPages(pgoff_t *filelen_table, inode_t inode)
 static void movePages(struct BattFsSuper *disk, pgcnt_t src, int offset)
 {
 	pgcnt_t dst = src + offset;
+	LOG_INFO("src %d, offset %d, size %ld\n", src, offset, (disk->page_count - MAX(dst, src)) * sizeof(pgcnt_t));
 	memmove(&disk->page_array[dst], &disk->page_array[src], (disk->page_count - MAX(dst, src)) * sizeof(pgcnt_t));
 
 	if (offset < 0)
@@ -221,136 +243,6 @@ static void movePages(struct BattFsSuper *disk, pgcnt_t src, int offset)
 	}
 }
 
-/**
- * Insert \a page into page allocation array of \a disk,
- * using  \a mark to compute position.
- */
-static void insertFreePage(struct BattFsSuper *disk, mark_t mark, pgcnt_t page)
-{
-	ASSERT(mark - disk->free_start < disk->free_next - disk->free_start);
-
-	pgcnt_t free_pos = disk->page_count - disk->free_next + mark;
-	ASSERT(free_pos < disk->page_count);
-
-	TRACEMSG("mark:%u, page:%u, free_start:%u, free_next:%u, free_pos:%u\n",
-		mark, page, disk->free_start, disk->free_next, free_pos);
-
-	ASSERT(disk->page_array[free_pos] == PAGE_UNSET_SENTINEL);
-	disk->page_array[free_pos] = page;
-}
-
-/**
- * Mark \a page of \a disk as free.
- * \note free_next of \a disk is used as \a page free marker
- * and is increased by 1.
- */
-static bool battfs_markFree(struct BattFsSuper *disk, struct BattFsPageHeader *hdr, pgcnt_t page)
-{
-	uint8_t buf[BATTFS_HEADER_LEN];
-
-	hdr->mark = disk->free_next;
-	hdr->fcs_free = computeFcsFree(hdr);
-	battfs_to_disk(hdr, buf);
-
-	if (!disk->write(disk, page, disk->page_size - BATTFS_HEADER_LEN, buf, BATTFS_HEADER_LEN))
-	{
-		TRACEMSG("error marking page [%d]\n", page);
-		return false;
-	}
-	else
-	{
-		disk->free_next++;
-		return true;
-	}
-}
-
-/**
- * Determine free_start and free_next blocks for \a disk
- * using \a minl, \a maxl, \a minh, \a maxh.
- *
- * Mark_t is a type that has at least 1 bit more than
- * pgaddr_t. So all free blocks can be numbered using
- * at most half numbers of a mark_t type.
- * The free blocks algorithm increments by 1 the disk->free_next
- * every time a page becomes free. So the free block 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.
- */
-static void findFreeStartNext(struct BattFsSuper *disk, mark_t minl, mark_t maxl, mark_t minh, mark_t maxh)
-{
-	/* Determine free_start & free_next */
-	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 lower half and ends in upper */
-				disk->free_start = minl;
-				disk->free_next = maxh;
-			}
-			else
-			{
-				/* Interval starts in upper half and ends in lower */
-				ASSERT(minl == 0);
-				ASSERT(maxh == (MAX_PAGE_ADDR | MARK_HALF_SIZE));
-
-				disk->free_start = minh;
-				disk->free_next = maxl;
-			}
-		}
-		else
-		{
-			/*
-			 * Upper interval is invalid.
-			 * Use lower values.
-			 */
-
-			disk->free_start = minl;
-			disk->free_next = maxl;
-		}
-	}
-	else if (maxh >= minh)
-	{
-		/*
-		 * Lower interval is invalid.
-		 * Use upper values.
-		 */
-		disk->free_start = minh;
-		disk->free_next = maxh;
-	}
-	else
-	{
-		/*
-		 * No valid interval found.
-		 * Hopefully the disk is brand new (or full).
-		 */
-		TRACEMSG("No valid marked free block found, new disk or disk full\n");
-		disk->free_start = 0;
-		disk->free_next = -1; //to be increased later
-	}
-
-	/* free_next should contain the first usable address */
-	disk->free_next++;
-
-	TRACEMSG("Free markers:\n minl %u\n maxl %u\n minh %u\n maxh %u\n free_start %u\n free_next %u\n",
-		minl, maxl, minh, maxh, disk->free_start, disk->free_next);
-}
-
 /**
  * Count number of pages per file on \a disk.
  * This information is registered in \a filelen_table.
@@ -363,19 +255,12 @@ static void findFreeStartNext(struct BattFsSuper *disk, mark_t minl, mark_t maxl
 static bool countDiskFilePages(struct BattFsSuper *disk, pgoff_t *filelen_table)
 {
 	BattFsPageHeader hdr;
-	mark_t minl, maxl, minh, maxh;
-
-	/* Initialize min and max counters to keep trace od free blocks */
-	minl = MAX_PAGE_ADDR;
-	maxl = 0;
-	minh = MAX_PAGE_ADDR | MARK_HALF_SIZE;
-	maxh = 0 | MARK_HALF_SIZE;
-
+	disk->free_page_start = 0;
 
 	/* Count the number of disk page per file */
 	for (pgcnt_t page = 0; page < disk->page_count; page++)
 	{
-		if (!battfs_readHeader(disk, page, &hdr))
+		if (!readHdr(disk, page, &hdr))
 			return false;
 
 		/* Increase free space */
@@ -384,8 +269,6 @@ static bool countDiskFilePages(struct BattFsSuper *disk, pgoff_t *filelen_table)
 		/* Check header FCS */
 		if (hdr.fcs == computeFcs(&hdr))
 		{
-			ASSERT(hdr.mark == MARK_PAGE_VALID);
-			ASSERT(hdr.fcs_free == FCS_FREE_VALID);
 			ASSERT(hdr.fill <= disk->page_size - BATTFS_HEADER_LEN);
 
 			/* Page is valid and is owned by a file */
@@ -393,32 +276,11 @@ static bool countDiskFilePages(struct BattFsSuper *disk, pgoff_t *filelen_table)
 
 			/* Keep trace of free space */
 			disk->free_bytes -= hdr.fill;
-		}
-		else
-		{
-			/* Check if page is marked free */
-			if (hdr.fcs_free == computeFcsFree(&hdr))
-			{
-				/*
-				 * This page is a valid and marked free page.
-				 * Update min and max free page markers.
-				 */
-				if (hdr.mark < MARK_HALF_SIZE)
-				{
-					minl = MIN(minl, hdr.mark);
-					maxl = MAX(maxl, hdr.mark);
-				}
-				else
-				{
-					minh = MIN(minh, hdr.mark);
-					maxh = MAX(maxh, hdr.mark);
-				}
-			}
-			else
-				TRACEMSG("page [%d] invalid, keeping as free\n", page);
+			disk->free_page_start++;
 		}
 	}
-	findFreeStartNext(disk, minl, maxl, minh, maxh);
+	LOG_INFO("free_bytes:%d, free_page_start:%d\n", disk->free_bytes, disk->free_page_start);
+
 	return true;
 }
 
@@ -431,62 +293,64 @@ static bool countDiskFilePages(struct BattFsSuper *disk, pgoff_t *filelen_table)
  * 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)
 {
 	BattFsPageHeader hdr;
+	pgcnt_t curr_free_page = disk->free_page_start;
 	/* Fill page allocation array */
 	for (pgcnt_t page = 0; page < disk->page_count; page++)
 	{
-		if (!battfs_readHeader(disk, page, &hdr))
+		if (!readHdr(disk, page, &hdr))
 			return false;
 
 		/* Check header FCS */
 		if (hdr.fcs == computeFcs(&hdr))
 		{
-			/* Page is valid and is owned by a file */
-			ASSERT(hdr.mark == MARK_PAGE_VALID);
-			ASSERT(hdr.fcs_free == FCS_FREE_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 (LIKELY(disk->page_array[array_pos] == PAGE_UNSET_SENTINEL))
+			if (disk->page_array[array_pos] == PAGE_UNSET_SENTINEL)
 				disk->page_array[array_pos] = page;
 			else
 			{
-				BattFsPageHeader hdr_old;
+				BattFsPageHeader hdr_prv;
 
-				if (!battfs_readHeader(disk, disk->page_array[array_pos], &hdr_old))
+				if (!readHdr(disk, disk->page_array[array_pos], &hdr_prv))
 					return false;
 
 				/* Check header FCS */
-				ASSERT(hdr_old.fcs == computeFcs(&hdr_old));
+				ASSERT(hdr_prv.fcs == computeFcs(&hdr_prv));
 
 				/* 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.fcs_free == hdr_old.fcs_free);
-				ASSERT(hdr.seq != hdr_old.seq);
+				ASSERT(hdr.inode == hdr_prv.inode);
+				ASSERT(hdr.pgoff == hdr_prv.pgoff);
+				ASSERT(hdr.seq != hdr_prv.seq);
 
 				pgcnt_t new_page, old_page;
 				fill_t old_fill;
 
-				/* Fancy check to handle seq wraparound (2 bits only) */
-				if (((hdr.seq - hdr_old.seq) & 0x03) < 2)
+				/*
+				 * Sequence number comparison: since
+				 * seq is 40 bits wide, it wraps once
+				 * every 1.1E12 times.
+				 * The memory will not live enough to
+				 * see a wraparound, so we can use a simple
+				 * compare here.
+				 */
+				if (hdr.seq > hdr_prv.seq)
 				{
 					/* Current header is newer than the previuos one */
 					old_page = disk->page_array[array_pos];
 					new_page = page;
-					old_fill = hdr_old.fill;
+					old_fill = hdr_prv.fill;
 				}
 				else
 				{
@@ -498,38 +362,77 @@ static bool fillPageArray(struct BattFsSuper *disk, pgoff_t *filelen_table)
 
 				/* 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 */
+				/* Move back all indexes */
 				filelen_table[hdr.inode]--;
+				disk->free_page_start--;
+				curr_free_page--;
+				/* Set old page as free */
+				ASSERT(disk->page_array[curr_free_page] == PAGE_UNSET_SENTINEL);
+				disk->page_array[curr_free_page++] = old_page;
 
-				/* Add old page to free pages pool */
-				if (!battfs_markFree(disk, &hdr, old_page))
-					return false;
-
-				insertFreePage(disk, hdr.mark, old_page);
 			}
 		}
 		else
 		{
-			/* Check if page is free */
-			if (hdr.fcs_free != computeFcsFree(&hdr))
-				/* Page is not a valid marked page, insert at list beginning */
-				hdr.mark = --disk->free_start;
-
-			insertFreePage(disk, hdr.mark, page);
+			/* Invalid page, keep as free */
+			ASSERT(disk->page_array[curr_free_page] == PAGE_UNSET_SENTINEL);
+			LOG_INFO("Page %d invalid, keeping as free\n", page);
+			disk->page_array[curr_free_page++] = page;
 		}
 	}
 	return true;
 }
 
+
+/**
+ * Flush the current \a disk buffer.
+ * \return true if ok, false on errors.
+ */
+static bool flushBuffer(struct BattFsSuper *disk)
+{
+	if (disk->cache_dirty)
+	{
+		LOG_INFO("Flushing to disk page %d\n", disk->curr_page);
+
+		if (!(disk->erase(disk, disk->curr_page)
+			&& disk->save(disk, disk->curr_page)))
+			return false;
+
+		disk->cache_dirty = false;
+	}
+	return true;
+}
+
+/**
+ * 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. The new page header loaded will be put in \a new_hdr.
+ * \return true if ok, false on errors.
+ */
+static bool loadPage(struct BattFsSuper *disk, pgcnt_t new_page, BattFsPageHeader *new_hdr)
+{
+	if (disk->curr_page == new_page)
+		return true;
+
+	LOG_INFO("Loading page %d\n", new_page);
+
+	if (!(flushBuffer(disk)
+		&& disk->load(disk, new_page)
+		&& getBufferHdr(disk, new_hdr)))
+		return false;
+
+	disk->curr_page = new_page;
+
+	return true;
+}
+
+
 /**
  * Initialize and mount disk described by
  * \a disk.
@@ -545,13 +448,16 @@ bool battfs_init(struct BattFsSuper *disk)
 	/* Init disk device */
 	if (!disk->open(disk))
 	{
-		TRACEMSG("open error\n");
+		LOG_ERR("open error\n");
 		return false;
 	}
 
 	/* Disk open must set all of these */
 	ASSERT(disk->read);
-	ASSERT(disk->write);
+	ASSERT(disk->load);
+	ASSERT(disk->bufferWrite);
+	ASSERT(disk->bufferRead);
+	ASSERT(disk->save);
 	ASSERT(disk->erase);
 	ASSERT(disk->close);
 	ASSERT(disk->page_size);
@@ -564,10 +470,15 @@ bool battfs_init(struct BattFsSuper *disk)
 	disk->free_bytes = 0;
 	disk->disk_size = (disk_size_t)(disk->page_size - BATTFS_HEADER_LEN) * disk->page_count;
 
+	/* Initialize page buffer cache */
+	disk->cache_dirty = false;
+	disk->curr_page = 0;
+	disk->load(disk, disk->curr_page);
+
 	/* Count pages per file */
 	if (!countDiskFilePages(disk, filelen_table))
 	{
-		TRACEMSG("error counting file pages\n");
+		LOG_ERR("counting file pages\n");
 		return false;
 	}
 
@@ -580,10 +491,16 @@ bool battfs_init(struct BattFsSuper *disk)
 	/* Fill page allocation array using filelen_table */
 	if (!fillPageArray(disk, filelen_table))
 	{
-		TRACEMSG("error filling page array\n");
+		LOG_ERR("filling page array\n");
 		return false;
 	}
-
+	#if LOG_LEVEL > LOG_LVL_INFO
+		dumpPageArray(disk)
+	#endif
+	#warning TODO: shuffle free blocks
+	//#if LOG_LEVEL > LOG_LVL_INFO
+	//	dumpPageArray(disk)
+	//#endif
 	/* Init list for opened files. */
 	LIST_INIT(&disk->file_opened_list);
 	return true;
@@ -595,9 +512,12 @@ bool battfs_init(struct BattFsSuper *disk)
  */
 static int battfs_flush(struct KFile *fd)
 {
-	(void)fd;
-	#warning TODO
-	return 0;
+	BattFs *fdb = BATTFS_CAST(fd);
+
+	if (flushBuffer(fdb->disk))
+		return 0;
+	else
+		return EOF;
 }
 
 /**
@@ -606,20 +526,138 @@ static int battfs_flush(struct KFile *fd)
  */
 static int battfs_fileclose(struct KFile *fd)
 {
-	BattFS *fdb = BATTFSKFILE(fd);
+	BattFs *fdb = BATTFS_CAST(fd);
 
 	battfs_flush(fd);
 	REMOVE(&fdb->link);
 	return 0;
 }
 
+
+static bool getNewPage(struct BattFsSuper *disk, pgcnt_t new_pos, inode_t inode, pgoff_t pgoff, BattFsPageHeader *new_hdr)
+{
+	if (disk->free_page_start >= disk->page_count)
+	{
+		#warning TODO space over!
+		LOG_INFO("No disk space available\n");
+		return false;
+	}
+	flushBuffer(disk);
+	LOG_INFO("Getting new page %d, pos %d\n", disk->page_array[disk->free_page_start], new_pos);
+	disk->curr_page = disk->page_array[disk->free_page_start++];
+	memmove(&disk->page_array[new_pos + 1], &disk->page_array[new_pos], (disk->free_page_start - new_pos - 1) * sizeof(pgcnt_t));
+
+	Node *n;
+	/* Move following file start point one position ahead. */
+	FOREACH_NODE(n, &disk->file_opened_list)
+	{
+		BattFs *file = containerof(n, BattFs, link);
+		if (file->inode > inode)
+		{
+			LOG_INFO("Move file %d start pos\n", file->inode);
+			file->start++;
+		}
+	}
+
+	disk->page_array[new_pos] = disk->curr_page;
+	disk->cache_dirty = true;
+
+	new_hdr->inode = inode;
+	new_hdr->pgoff =  pgoff;
+	new_hdr->fill = 0;
+	new_hdr->seq = 0;
+	return setBufferHdr(disk, new_hdr);
+}
+
+/**
+ * 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;
+
+	BattFsPageHeader curr_hdr;
+	if (!getBufferHdr(fdb->disk, &curr_hdr))
+		return total_write;
+
+	#warning TODO seek_pos > size?
+
+	while (size)
+	{
+		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));
+
+		/* Handle write outside EOF */
+		if (pg_offset > fdb->max_off)
+		{
+			LOG_INFO("New page needed, pg_offset %d, pos %d\n", pg_offset, (fdb->start - fdb->disk->page_array) + pg_offset);
+			if (!getNewPage(fdb->disk, (fdb->start - fdb->disk->page_array) + pg_offset, fdb->inode, pg_offset, &curr_hdr))
+				return total_write;
+			fdb->max_off = pg_offset;
+		}
+		/* Handle cache load of a new page*/
+		else if (fdb->start[pg_offset] != fdb->disk->curr_page)
+		{
+			LOG_INFO("Re-writing page %d to %d\n", fdb->start[pg_offset], fdb->disk->page_array[fdb->disk->free_page_start]);
+			if (!loadPage(fdb->disk, fdb->start[pg_offset], &curr_hdr))
+			{
+				#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 */
+			LOG_INFO("Setting page %d as free\n", fdb->start[pg_offset]);
+			fdb->disk->page_array[fdb->disk->page_count - 1] = fdb->start[pg_offset];
+			/* Assign new page */
+			fdb->start[pg_offset] = fdb->disk->curr_page;
+			curr_hdr.seq++;
+		}
+
+
+		//LOG_INFO("writing to buffer for page %d, offset %d, size %d\n", fdb->disk->curr_page, addr_offset, wr_len);
+		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;
+		fill_t fill_delta = MAX((int32_t)(addr_offset + wr_len) - curr_hdr.fill, (int32_t)0);
+		fdb->disk->free_bytes -= fill_delta;
+		fd->size += fill_delta;
+		curr_hdr.fill += fill_delta;
+
+		if (!setBufferHdr(fdb->disk, &curr_hdr))
+			return total_write;
+
+		//LOG_INFO("free_bytes %d, seek_pos %d, size %d, curr_hdr.fill %d\n", fdb->disk->free_bytes, fd->seek_pos, fd->size, curr_hdr.fill);
+	}
+	return total_write;
+}
+
+
 /**
  * Read from file \a fd \a size bytes in \a buf.
  * \return The number of bytes read.
  */
 static size_t battfs_read(struct KFile *fd, void *_buf, size_t size)
 {
-	BattFS *fdb = BATTFSKFILE(fd);
+	BattFs *fdb = BATTFS_CAST(fd);
 	uint8_t *buf = (uint8_t *)_buf;
 
 	size_t total_read = 0;
@@ -636,11 +674,17 @@ static size_t battfs_read(struct KFile *fd, void *_buf, size_t size)
 		read_len = MIN(size, (size_t)(fdb->disk->page_size - BATTFS_HEADER_LEN - addr_offset));
 
 		/* Read from disk */
-		if (fdb->disk->read(fdb->disk, fdb->start[pg_offset], addr_offset, buf, read_len) != read_len)
+		if (diskRead(fdb->disk, fdb->start[pg_offset], addr_offset, buf, read_len) != read_len)
 		{
 			#warning TODO set error?
 		}
 
+		#if _DEBUG
+			BattFsPageHeader hdr;
+			readHdr(fdb->disk, fdb->start[pg_offset], &hdr);
+			ASSERT(hdr.inode == fdb->inode);
+		#endif
+
 		size -= read_len;
 		fd->seek_pos += read_len;
 		total_read += read_len;
@@ -652,32 +696,40 @@ static size_t battfs_read(struct KFile *fd, void *_buf, size_t size)
 
 /**
  * Search file \a inode in \a disk using a binary search.
- * \return pointer to file start in disk->page_array
- * if file exists, NULL otherwise.
+ * \a last is filled with array offset of file start
+ * in disk->page_array if file is found, otherwise
+ * \a last is filled with the correct insert position
+ * for creating a file with the given \a inode.
+ * \return true if file is found, false otherwisr.
  */
-static pgcnt_t *findFile(BattFsSuper *disk, inode_t inode)
+static bool findFile(BattFsSuper *disk, inode_t inode, pgcnt_t *last)
 {
 	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;
-
-		if (!battfs_readHeader(disk, disk->page_array[page], &hdr))
-			return NULL;
-
+		page = (first + *last) / 2;
+		LOG_INFO("first %d, last %d, page %d\n", first, *last, page);
+		if (!readHdr(disk, disk->page_array[page], &hdr))
+			return false;
+		LOG_INFO("inode read: %d\n", hdr.inode);
 		fcs = computeFcs(&hdr);
 		if (hdr.fcs == fcs && hdr.inode == inode)
-			return (&disk->page_array[page]) - hdr.pgoff;
+		{
+			*last = page - hdr.pgoff;
+			LOG_INFO("Found: %d\n", *last);
+			return true;
+		}
 		else if (hdr.fcs == fcs && hdr.inode < inode)
 			first = page + 1;
 		else
-			last = page - 1;
+			*last = page - 1;
 	}
-
-	return NULL;
+	LOG_INFO("Not found: last %d\n", *last);
+	return false;
 }
 
 /**
@@ -685,7 +737,8 @@ static pgcnt_t *findFile(BattFsSuper *disk, inode_t inode)
  */
 bool battfs_fileExists(BattFsSuper *disk, inode_t inode)
 {
-	return findFile(disk, inode) != NULL;
+	pgcnt_t dummy;
+	return findFile(disk, inode, &dummy);
 }
 
 /**
@@ -693,20 +746,21 @@ bool battfs_fileExists(BattFsSuper *disk, inode_t inode)
  * 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 (;;)
+	while (start < &disk->page_array[disk->free_page_start])
 	{
-		if (!battfs_readHeader(disk, *start++, &hdr))
-			return false;
+		if (!readHdr(disk, *start++, &hdr))
+			return EOF;
 		if (hdr.fcs == computeFcs(&hdr) && hdr.inode == inode)
-			*size += hdr.fill;
+			size += hdr.fill;
 		else
-			return true;
+			break;
 	}
+	return size;
 }
 
 /**
@@ -714,34 +768,31 @@ static bool countFileSize(BattFsSuper *disk, pgcnt_t *start, inode_t inode, file
  * File context is stored in \a fd.
  * \return true if ok, false otherwise.
  */
-bool battfs_fileopen(BattFsSuper *disk, BattFS *fd, inode_t inode, filemode_t mode)
+bool battfs_fileopen(BattFsSuper *disk, BattFs *fd, inode_t inode, filemode_t mode)
 {
 	Node *n;
 
 	memset(fd, 0, sizeof(*fd));
 
 	/* Search file start point in disk page array */
-	fd->start = findFile(disk, inode);
-	if (fd->start == NULL)
+	pgcnt_t start_pos;
+	if (!findFile(disk, inode, &start_pos))
 	{
+		LOG_INFO("file %d not found\n", inode);
 		if (!(mode & BATTFS_CREATE))
 			return false;
-
-		/* File does not exist, create it */
+		/* Create the file */
 		BattFsPageHeader hdr;
-		hdr.inode = inode;
-		hdr.seq = 0;
-		hdr.fill = 0;
-		hdr.pgoff = 0;
-		hdr.mark = MARK_PAGE_VALID;
-		hdr.fcs_free = FCS_FREE_VALID;
-		hdr.fcs = computeFcs(&hdr);
-		#warning TODO: get a free block and write on disk!
+		if (!(getNewPage(disk, start_pos, inode, 0, &hdr)))
+			return false;
 	}
+	fd->start = &disk->page_array[start_pos];
+	LOG_INFO("Start pos %d\n", start_pos);
 
 	/* Fill file size */
-	if (!countFileSize(disk, fd->start, inode, &fd->fd.size))
+	if ((fd->fd.size = countFileSize(disk, fd->start, inode)) == EOF)
 		return false;
+	fd->max_off = fd->fd.size / (disk->page_size - BATTFS_HEADER_LEN);
 
 	/* Reset seek position */
 	fd->fd.seek_pos = 0;
@@ -749,7 +800,7 @@ bool battfs_fileopen(BattFsSuper *disk, BattFS *fd, inode_t inode, filemode_t mo
 	/* Insert file handle in list, ordered by inode, ascending. */
 	FOREACH_NODE(n, &disk->file_opened_list)
 	{
-		BattFS *file = containerof(n, BattFS, link);
+		BattFs *file = containerof(n, BattFs, link);
 		if (file->inode >= inode)
 			break;
 	}
@@ -765,10 +816,10 @@ bool battfs_fileopen(BattFsSuper *disk, BattFS *fd, inode_t inode, filemode_t mo
 	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
@@ -789,7 +840,7 @@ bool battfs_close(struct BattFsSuper *disk)
 	/* Close all open files */
 	FOREACH_NODE(n, &disk->file_opened_list)
 	{
-		BattFS *file = containerof(n, BattFS, link);
+		BattFs *file = containerof(n, BattFs, link);
 		res += battfs_fileclose(&file->fd);
 	}
 
@@ -797,29 +848,29 @@ bool battfs_close(struct BattFsSuper *disk)
 	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, mark_t mark)
+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.seq = seq;
 	hdr.fill = fill;
 	hdr.pgoff = pgoff;
-	hdr.mark = MARK_PAGE_VALID;
-	hdr.fcs_free = FCS_FREE_VALID;
+	hdr.seq = seq;
 	hdr.fcs = computeFcs(&hdr);
-	if (mark != MARK_PAGE_VALID)
-	{
-		hdr.mark = mark;
-		hdr.fcs_free = computeFcsFree(&hdr);
-	}
 
-	if (!battfs_writeHeader(disk, page, &hdr))
+	if (!(setBufferHdr(disk, &hdr) && disk->save(disk, page)))
 	{
-		TRACEMSG("error writing hdr\n");
+		LOG_ERR("error writing hdr\n");
 		return false;
 	}
 
 	return true;
 }
+#endif