Commit 0f9268b8 authored by Andrew Morton's avatar Andrew Morton Committed by Arnaldo Carvalho de Melo

[PATCH] fix dirty page management

This fixes a bug in ext3 - when ext3 decides that it wants to fail its
writepage(), it is running SetPageDirty().  But ->writepage has just put
the page on ->clean_pages().  The page ends up dirty, on ->clean_pages
and the normal writeback paths don't know about it any more.

So run set_page_dirty() instead, to place the page back on the dirty
list.

And in move_from_swap_cache(), shuffle the page across to ->dirty_pages
so that it's eligible for writeout.  ___add_to_page_cache() forgets to
look at the page state when deciding which list to attach it to.

All SetPageDirty() callers otherwise look OK.
parent 43152186
......@@ -1325,7 +1325,7 @@ static int ext3_writepage(struct page *page)
out_fail:
unlock_kernel();
SetPageDirty(page);
set_page_dirty(page);
unlock_page(page);
return ret;
}
......
......@@ -425,6 +425,9 @@ void invalidate_inode_pages2(struct address_space * mapping)
* - activate the page so that the page stealer
* doesn't try to write it out over and over
* again.
*
* NOTE! The livelock in fdatasync went away, due to io_pages.
* So this function can now call set_page_dirty().
*/
int fail_writepage(struct page *page)
{
......
......@@ -220,8 +220,16 @@ int move_from_swap_cache(struct page *page, unsigned long index,
page->flags &= ~(1 << PG_uptodate | 1 << PG_error |
1 << PG_referenced | 1 << PG_arch_1 |
1 << PG_checked);
/*
* ___add_to_page_cache puts the page on ->clean_pages,
* but it's dirty. If it's on ->clean_pages, it will basically
* never get written out.
*/
SetPageDirty(page);
___add_to_page_cache(page, mapping, index);
/* fix that up */
list_del(&page->list);
list_add(&page->list, &mapping->dirty_pages);
}
write_unlock(&mapping->page_lock);
......
......@@ -311,6 +311,11 @@ int remove_exclusive_swap_page(struct page *page)
write_lock(&swapper_space.page_lock);
if (page_count(page) - !!PagePrivate(page) == 2) {
__delete_from_swap_cache(page);
/*
* NOTE: if/when swap gets buffer/page coherency
* like other mappings, we'll need to mark the buffers
* dirty here too. set_page_dirty().
*/
SetPageDirty(page);
retval = 1;
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment