+ if (dev->nDataBytesPerChunk & (dev->nDataBytesPerChunk - 1)) {
+ /* Do this if chunk size is not a power of 2 */
+
+ uint64_t bytesInDev;
+ uint64_t bytesFree;
+
+ bytesInDev = ((uint64_t)((dev->param.endBlock - dev->param.startBlock + 1))) *
+ ((uint64_t)(dev->param.nChunksPerBlock * dev->nDataBytesPerChunk));
+
+ do_div(bytesInDev, sb->s_blocksize); /* bytesInDev becomes the number of blocks */
+ buf->f_blocks = bytesInDev;
+
+ bytesFree = ((uint64_t)(yaffs_GetNumberOfFreeChunks(dev))) *
+ ((uint64_t)(dev->nDataBytesPerChunk));
+
+ do_div(bytesFree, sb->s_blocksize);
+
+ buf->f_bfree = bytesFree;
+
+ } else if (sb->s_blocksize > dev->nDataBytesPerChunk) {
+
+ buf->f_blocks =
+ (dev->param.endBlock - dev->param.startBlock + 1) *
+ dev->param.nChunksPerBlock /
+ (sb->s_blocksize / dev->nDataBytesPerChunk);
+ buf->f_bfree =
+ yaffs_GetNumberOfFreeChunks(dev) /
+ (sb->s_blocksize / dev->nDataBytesPerChunk);
+ } else {
+ buf->f_blocks =
+ (dev->param.endBlock - dev->param.startBlock + 1) *
+ dev->param.nChunksPerBlock *
+ (dev->nDataBytesPerChunk / sb->s_blocksize);
+
+ buf->f_bfree =
+ yaffs_GetNumberOfFreeChunks(dev) *
+ (dev->nDataBytesPerChunk / sb->s_blocksize);
+ }
+
+ buf->f_files = 0;
+ buf->f_ffree = 0;
+ buf->f_bavail = buf->f_bfree;
+
+ yaffs_GrossUnlock(dev);
+ return 0;
+}
+
+
+
+static void yaffs_FlushInodes(struct super_block *sb)
+{
+ struct inode *iptr;
+ yaffs_Object *obj;
+
+ list_for_each_entry(iptr,&sb->s_inodes, i_sb_list){
+ obj = yaffs_InodeToObject(iptr);
+ if(obj){
+ T(YAFFS_TRACE_OS, (TSTR("flushing obj %d\n"),
+ obj->objectId));
+ yaffs_FlushFile(obj,1,0);
+ }
+ }
+}
+
+
+static void yaffs_FlushSuperBlock(struct super_block *sb, int do_checkpoint)
+{
+ yaffs_Device *dev = yaffs_SuperToDevice(sb);
+ if(!dev)
+ return;
+
+ yaffs_FlushInodes(sb);
+ yaffs_UpdateDirtyDirectories(dev);
+ yaffs_FlushEntireDeviceCache(dev);
+ if(do_checkpoint)
+ yaffs_CheckpointSave(dev);
+}
+
+
+static unsigned yaffs_bg_gc_urgency(yaffs_Device *dev)
+{
+ unsigned erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
+ struct yaffs_LinuxContext *context = yaffs_DeviceToLC(dev);
+ unsigned scatteredFree = 0; /* Free chunks not in an erased block */
+
+ if(erasedChunks < dev->nFreeChunks)
+ scatteredFree = (dev->nFreeChunks - erasedChunks);
+
+ if(!context->bgRunning)
+ return 0;
+ else if(scatteredFree < (dev->param.nChunksPerBlock * 2))
+ return 0;
+ else if(erasedChunks > dev->nFreeChunks/2)
+ return 0;
+ else if(erasedChunks > dev->nFreeChunks/4)
+ return 1;
+ else
+ return 2;
+}
+
+static int yaffs_do_sync_fs(struct super_block *sb,
+ int request_checkpoint)
+{
+
+ yaffs_Device *dev = yaffs_SuperToDevice(sb);
+ unsigned int oneshot_checkpoint = (yaffs_auto_checkpoint & 4);
+ unsigned gc_urgent = yaffs_bg_gc_urgency(dev);
+ int do_checkpoint;
+
+ T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC | YAFFS_TRACE_BACKGROUND,
+ (TSTR("yaffs_do_sync_fs: gc-urgency %d %s %s%s\n"),
+ gc_urgent,
+ sb->s_dirt ? "dirty" : "clean",
+ request_checkpoint ? "checkpoint requested" : "no checkpoint",
+ oneshot_checkpoint ? " one-shot" : "" ));
+
+ yaffs_GrossLock(dev);
+ do_checkpoint = ((request_checkpoint && !gc_urgent) ||
+ oneshot_checkpoint) &&
+ !dev->isCheckpointed;
+
+ if (sb->s_dirt || do_checkpoint) {
+ yaffs_FlushSuperBlock(sb, !dev->isCheckpointed && do_checkpoint);
+ sb->s_dirt = 0;
+ if(oneshot_checkpoint)
+ yaffs_auto_checkpoint &= ~4;
+ }
+ yaffs_GrossUnlock(dev);
+
+ return 0;
+}
+
+/*
+ * yaffs background thread functions .
+ * yaffs_BackgroundThread() the thread function
+ * yaffs_BackgroundStart() launches the background thread.
+ * yaffs_BackgroundStop() cleans up the background thread.
+ *
+ * NB:
+ * The thread should only run after the yaffs is initialised
+ * The thread should be stopped before yaffs is unmounted.
+ * The thread should not do any writing while the fs is in read only.
+ */
+
+#ifdef YAFFS_COMPILE_BACKGROUND
+
+void yaffs_background_waker(unsigned long data)
+{
+ wake_up_process((struct task_struct *)data);
+}
+
+static int yaffs_BackgroundThread(void *data)
+{
+ yaffs_Device *dev = (yaffs_Device *)data;
+ struct yaffs_LinuxContext *context = yaffs_DeviceToLC(dev);
+ unsigned long now = jiffies;
+ unsigned long next_dir_update = now;
+ unsigned long next_gc = now;
+ unsigned long expires;
+ unsigned int urgency;
+
+ int gcResult;
+ struct timer_list timer;
+
+ T(YAFFS_TRACE_BACKGROUND,
+ (TSTR("yaffs_background starting for dev %p\n"),
+ (void *)dev));
+
+ set_freezable();
+
+ while(context->bgRunning){
+ T(YAFFS_TRACE_BACKGROUND,
+ (TSTR("yaffs_background\n")));
+
+ if(kthread_should_stop())
+ break;
+
+ if(try_to_freeze())
+ continue;
+
+ yaffs_GrossLock(dev);
+
+ now = jiffies;