#include <linux/kernel.h>
#include <linux/fs.h>
+#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/blkdev.h>
if (!ra->ra_pages)
return;
+ /* be dumb */
+ if (filp && (filp->f_mode & FMODE_RANDOM)) {
+ force_page_cache_readahead(mapping, filp, offset, req_size);
+ return;
+ }
+
/* do read-ahead */
ondemand_readahead(mapping, ra, filp, false, offset, req_size);
}
* @req_size: hint: total size of the read which the caller is performing in
* pagecache pages
*
- * page_cache_async_ondemand() should be called when a page is used which
+ * page_cache_async_readahead() should be called when a page is used which
* has the PG_readahead flag; this is a marker to suggest that the application
* has used up enough of the readahead window that we should start pulling in
* more pages.
/* do read-ahead */
ondemand_readahead(mapping, ra, filp, true, offset, req_size);
+
+#ifdef CONFIG_BLOCK
+ /*
+ * Normally the current page is !uptodate and lock_page() will be
+ * immediately called to implicitly unplug the device. However this
+ * is not always true for RAID conifgurations, where data arrives
+ * not strictly in their submission order. In this case we need to
+ * explicitly kick off the IO.
+ */
+ if (PageUptodate(page))
+ blk_run_backing_dev(mapping->backing_dev_info, NULL);
+#endif
}
EXPORT_SYMBOL_GPL(page_cache_async_readahead);