/* this gets called when the md device is ready to unplug its underlying
* (slave) device queues -- before we let any writes go down, we need to
* sync the dirty pages of the bitmap file to disk */
int bitmap_unplug(struct bitmap *bitmap)
{
unsigned long i, attr, flags;
struct page *page;
int wait = 0;
int err;
if (!bitmap)
return 0;
/* look at each page to see if there are any set bits that need to be
* flushed out to disk */
for (i = 0; i < bitmap->file_pages; i++) {
spin_lock_irqsave(&bitmap->lock, flags);
if (!bitmap->filemap) {
spin_unlock_irqrestore(&bitmap->lock, flags);
return 0;
}
page = bitmap->filemap[i];
attr = get_page_attr(bitmap, page);
clear_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
if ((attr & BITMAP_PAGE_DIRTY))
wait = 1;
spin_unlock_irqrestore(&bitmap->lock, flags);
if (attr & (BITMAP_PAGE_DIRTY | BITMAP_PAGE_NEEDWRITE)) {
err = write_page(bitmap, page, 0);
if (err == -EAGAIN) {
if (attr & BITMAP_PAGE_DIRTY)
err = write_page(bitmap, page, 1);
else
err = 0;
}
if (err)
return 1;
}
}
if (wait) { /* if any writes were performed, we need to wait on them */
if (bitmap->file) {
spin_lock_irq(&bitmap->write_lock);
wait_event_lock_irq(bitmap->write_wait,
list_empty(&bitmap->complete_pages), bitmap->write_lock,
wake_up_process(bitmap->writeback_daemon->tsk));
spin_unlock_irq(&bitmap->write_lock);
} else
md_super_wait(bitmap->mddev);
}
return 0;
}
/* this gets called when the md device is ready to unplug its underlying
* (slave) device queues -- before we let any writes go down, we need to
* sync the dirty pages of the bitmap file to disk */
int bitmap_unplug(struct bitmap *bitmap)
{
unsigned long i, flags;
int dirty, need_write;
struct page *page;
int wait = 0;
int err;
if (!bitmap)
return 0;
/* look at each page to see if there are any set bits that need to be
* flushed out to disk */
for (i = 0; i < bitmap->file_pages; i++) {
spin_lock_irqsave(&bitmap->lock, flags);
if (!bitmap->filemap) {
spin_unlock_irqrestore(&bitmap->lock, flags);
return 0;
}
page = bitmap->filemap[i];
dirty = test_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
need_write = test_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
clear_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
if (dirty)
wait = 1;
spin_unlock_irqrestore(&bitmap->lock, flags);
if (dirty | need_write)
err = write_page(bitmap, page, 0);
}
if (wait) { /* if any writes were performed, we need to wait on them */
if (bitmap->file)
wait_event(bitmap->write_wait,
atomic_read(&bitmap->pending_writes)==0);
else
md_super_wait(bitmap->mddev);
}
if (bitmap->flags & BITMAP_WRITE_ERROR)
bitmap_file_kick(bitmap);
return 0;
}
