};
/*
- * A control structure which tells the writeback code what to do
+ * A control structure which tells the writeback code what to do. These are
+ * always on the stack, and hence need no locking. They are always initialised
+ * in a manner such that unspecified fields are set to zero.
*/
struct writeback_control {
struct backing_dev_info *bdi; /* If !NULL, only write back this
long nr_to_write; /* Write this many pages, and decrement
this for each page written */
long pages_skipped; /* Pages which were not written */
- int nonblocking; /* Don't get stuck on request queues */
- int encountered_congestion; /* An output: a queue is full */
- int for_kupdate; /* A kupdate writeback */
- int for_reclaim; /* Invoked from the page allocator */
+
+ /*
+ * For a_ops->writepages(): is start or end are non-zero then this is
+ * a hint that the filesystem need only write out the pages inside that
+ * byterange. The byte at `end' is included in the writeout request.
+ */
+ loff_t start;
+ loff_t end;
+
+ unsigned nonblocking:1; /* Don't get stuck on request queues */
+ unsigned encountered_congestion:1; /* An output: a queue is full */
+ unsigned for_kupdate:1; /* A kupdate writeback */
+ unsigned for_reclaim:1; /* Invoked from the page allocator */
};
/*
/* writeback.h requires fs.h; it, too, is not included from here. */
static inline void wait_on_inode(struct inode *inode)
{
+ might_sleep();
if (inode->i_state & I_LOCK)
__wait_on_inode(inode);
}
void balance_dirty_pages_ratelimited(struct address_space *mapping);
int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0);
int do_writepages(struct address_space *mapping, struct writeback_control *wbc);
+int sync_page_range(struct inode *inode, struct address_space *mapping,
+ loff_t pos, size_t count);
/* pdflush.c */
extern int nr_pdflush_threads; /* Global so it can be exported to sysctl