* pages against inodes. ie: data writeback. Writeout of the
* inode itself is not handled here.
*
- * 10Apr2002 akpm@zip.com.au
+ * 10Apr2002 Andrew Morton
* Split out of fs/inode.c
* Additions for address_space-based writeback
*/
* If we're a pdlfush thread, then implement pdflush collision avoidance
* against the entire list.
*
- * WB_SYNC_HOLD is a hack for sys_sync(): reattach the inode to sb->s_dirty so
- * that it can be located for waiting on in __writeback_single_inode().
- *
* If `bdi' is non-zero then we're being asked to writeback a specific queue.
* This function assumes that the blockdev superblock's inodes are backed by
* a variety of queues, so all inodes are searched. For other superblocks,
* on the writer throttling path, and we get decent balancing between many
* throttled threads: we don't want them all piling up on inode_sync_wait.
*/
-static void
-sync_sb_inodes(struct super_block *sb, struct writeback_control *wbc)
+void generic_sync_sb_inodes(struct super_block *sb,
+ struct writeback_control *wbc)
{
const unsigned long start = jiffies; /* livelock avoidance */
+ int sync = wbc->sync_mode == WB_SYNC_ALL;
spin_lock(&inode_lock);
if (!wbc->for_kupdate || list_empty(&sb->s_io))
__iget(inode);
pages_skipped = wbc->pages_skipped;
__writeback_single_inode(inode, wbc);
- if (wbc->sync_mode == WB_SYNC_HOLD) {
- inode->dirtied_when = jiffies;
- list_move(&inode->i_list, &sb->s_dirty);
- }
if (current_is_pdflush())
writeback_release(bdi);
if (wbc->pages_skipped != pages_skipped) {
if (!list_empty(&sb->s_more_io))
wbc->more_io = 1;
}
- spin_unlock(&inode_lock);
+
+ if (sync) {
+ struct inode *inode, *old_inode = NULL;
+
+ /*
+ * Data integrity sync. Must wait for all pages under writeback,
+ * because there may have been pages dirtied before our sync
+ * call, but which had writeout started before we write it out.
+ * In which case, the inode may not be on the dirty list, but
+ * we still have to wait for that writeout.
+ */
+ list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
+ struct address_space *mapping;
+
+ if (inode->i_state & (I_FREEING|I_WILL_FREE))
+ continue;
+ mapping = inode->i_mapping;
+ if (mapping->nrpages == 0)
+ continue;
+ __iget(inode);
+ spin_unlock(&inode_lock);
+ /*
+ * We hold a reference to 'inode' so it couldn't have
+ * been removed from s_inodes list while we dropped the
+ * inode_lock. We cannot iput the inode now as we can
+ * be holding the last reference and we cannot iput it
+ * under inode_lock. So we keep the reference and iput
+ * it later.
+ */
+ iput(old_inode);
+ old_inode = inode;
+
+ filemap_fdatawait(mapping);
+
+ cond_resched();
+
+ spin_lock(&inode_lock);
+ }
+ spin_unlock(&inode_lock);
+ iput(old_inode);
+ } else
+ spin_unlock(&inode_lock);
+
return; /* Leave any unwritten inodes on s_io */
}
+EXPORT_SYMBOL_GPL(generic_sync_sb_inodes);
+
+static void sync_sb_inodes(struct super_block *sb,
+ struct writeback_control *wbc)
+{
+ generic_sync_sb_inodes(sb, wbc);
+}
/*
* Start writeback of dirty pagecache data against all unlocked inodes.
/*
* writeback and wait upon the filesystem's dirty inodes. The caller will
- * do this in two passes - one to write, and one to wait. WB_SYNC_HOLD is
- * used to park the written inodes on sb->s_dirty for the wait pass.
+ * do this in two passes - one to write, and one to wait.
*
* A finite limit is set on the number of pages which will be written.
* To prevent infinite livelock of sys_sync().
void sync_inodes_sb(struct super_block *sb, int wait)
{
struct writeback_control wbc = {
- .sync_mode = wait ? WB_SYNC_ALL : WB_SYNC_HOLD,
+ .sync_mode = wait ? WB_SYNC_ALL : WB_SYNC_NONE,
.range_start = 0,
.range_end = LLONG_MAX,
};
- unsigned long nr_dirty = global_page_state(NR_FILE_DIRTY);
- unsigned long nr_unstable = global_page_state(NR_UNSTABLE_NFS);
- wbc.nr_to_write = nr_dirty + nr_unstable +
- (inodes_stat.nr_inodes - inodes_stat.nr_unused) +
- nr_dirty + nr_unstable;
- wbc.nr_to_write += wbc.nr_to_write / 2; /* Bit more for luck */
+ if (!wait) {
+ unsigned long nr_dirty = global_page_state(NR_FILE_DIRTY);
+ unsigned long nr_unstable = global_page_state(NR_UNSTABLE_NFS);
+
+ wbc.nr_to_write = nr_dirty + nr_unstable +
+ (inodes_stat.nr_inodes - inodes_stat.nr_unused);
+ } else
+ wbc.nr_to_write = LONG_MAX; /* doesn't actually matter */
+
sync_sb_inodes(sb, &wbc);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff