tag_pages_for_writeback (9) Linux Manual Page
tag_pages_for_writeback – tag pages to be written by write_cache_pages
Synopsis
void tag_pages_for_writeback(struct address_space *mapping, pgoff_t start, pgoff_t end);Arguments
mapping
-
- address space structure to write
start
- starting page index
end
- ending page index (inclusive)
Description
This function scans the page range from start to end (inclusive) and tags all pages that have DIRTY tag set with a special TOWRITE tag. The idea is that write_cache_pages (or whoever calls this function) will then use TOWRITE tag to identify pages eligible for writeback. This mechanism is used to avoid livelocking of writeback by a process steadily creating new dirty pages in the file (thus it is important for this function to be quick so that it can tag pages faster than a dirtying process can create them).