From: Zach Brown <zach.brown@oracle.com>
Now that we're only invalidating the pages that intersected a direct IO
write we might as well only unmap the intersecting bytes as well. This
passed a light fsx load with page cache, direct, and mmap IO.
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/mm/filemap.c | 12 ++++++++----
1 files changed, 8 insertions(+), 4 deletions(-)
diff -puN mm/filemap.c~only-unmap-what-intersects-a-direct_io-op mm/filemap.c
--- 25/mm/filemap.c~only-unmap-what-intersects-a-direct_io-op 2005-02-22 18:16:10.000000000 -0800
+++ 25-akpm/mm/filemap.c 2005-02-22 18:16:10.000000000 -0800
@@ -2285,22 +2285,26 @@ generic_file_direct_IO(int rw, struct ki
struct file *file = iocb->ki_filp;
struct address_space *mapping = file->f_mapping;
ssize_t retval;
+ size_t write_len = 0;
/*
* If it's a write, unmap all mmappings of the file up-front. This
* will cause any pte dirty bits to be propagated into the pageframes
* for the subsequent filemap_write_and_wait().
*/
- if (rw == WRITE && mapping_mapped(mapping))
- unmap_mapping_range(mapping, 0, -1, 0);
+ if (rw == WRITE) {
+ write_len = iov_length(iov, nr_segs);
+ if (mapping_mapped(mapping))
+ unmap_mapping_range(mapping, offset, write_len, 0);
+ }
retval = filemap_write_and_wait(mapping);
if (retval == 0) {
retval = mapping->a_ops->direct_IO(rw, iocb, iov,
offset, nr_segs);
if (rw == WRITE && mapping->nrpages) {
- pgoff_t end = (offset + iov_length(iov, nr_segs) - 1)
- >> PAGE_CACHE_SHIFT;
+ pgoff_t end = (offset + write_len - 1)
+ >> PAGE_CACHE_SHIFT;
int err = invalidate_inode_pages2_range(mapping,
offset >> PAGE_CACHE_SHIFT, end);
if (err)
_