Modify mpage_map_and_submit_buffers() to do writeback with huge pages.
This is somewhat unstable. I have hard time see full picture yet.
More work is required.
Not-yet-signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
fs/ext4/inode.c | 40 ++++++++++++++++++++++++++--------------
1 file changed, 26 insertions(+), 14 deletions(-)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 2e22f62f007b..29133e4550fc 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2088,16 +2088,16 @@ static int mpage_submit_page(struct mpage_da_data *mpd, struct page *page)
loff_t size = i_size_read(mpd->inode);
int err;
- BUG_ON(page->index != mpd->first_page);
- if (page->index == size >> PAGE_SHIFT)
- len = size & ~PAGE_MASK;
- else
- len = PAGE_SIZE;
+ page = compound_head(page);
+ len = hpage_size(page);
+ if (page->index + hpage_nr_pages(page) - 1 == size >> PAGE_SHIFT)
+ len = size & ~hpage_mask(page);
+
clear_page_dirty_for_io(page);
err = ext4_bio_write_page(&mpd->io_submit, page, len, mpd->wbc, false);
if (!err)
- mpd->wbc->nr_to_write--;
- mpd->first_page++;
+ mpd->wbc->nr_to_write -= hpage_nr_pages(page);
+ mpd->first_page = round_up(mpd->first_page + 1, hpage_nr_pages(page));
return err;
}
@@ -2245,12 +2245,16 @@ static int mpage_map_and_submit_buffers(struct mpage_da_data *mpd)
break;
for (i = 0; i < nr_pages; i++) {
struct page *page = pvec.pages[i];
+ unsigned long diff;
- if (page->index > end)
+ if (page_to_pgoff(page) > end)
break;
/* Up to 'end' pages must be contiguous */
- BUG_ON(page->index != start);
+ BUG_ON(page_to_pgoff(page) != start);
+ diff = (page - compound_head(page)) << bpp_bits;
bh = head = page_buffers(page);
+ while (diff--)
+ bh = bh->b_this_page;
do {
if (lblk < mpd->map.m_lblk)
continue;
@@ -2287,7 +2291,10 @@ static int mpage_map_and_submit_buffers(struct mpage_da_data *mpd)
* supports blocksize < pagesize as we will try to
* convert potentially unmapped parts of inode.
*/
- mpd->io_submit.io_end->size += PAGE_SIZE;
+ if (PageTransCompound(page))
+ mpd->io_submit.io_end->size += HPAGE_PMD_SIZE;
+ else
+ mpd->io_submit.io_end->size += PAGE_SIZE;
/* Page fully mapped - let IO run! */
err = mpage_submit_page(mpd, page);
if (err < 0) {
@@ -2295,6 +2302,10 @@ static int mpage_map_and_submit_buffers(struct mpage_da_data *mpd)
return err;
}
start++;
+ if (PageTransCompound(page)) {
+ start = round_up(start, HPAGE_PMD_NR);
+ break;
+ }
}
pagevec_release(&pvec);
}
@@ -2534,7 +2545,7 @@ static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd)
* mapping. However, page->index will not change
* because we have a reference on the page.
*/
- if (page->index > end)
+ if (page_to_pgoff(page) > end)
goto out;
/*
@@ -2563,7 +2574,7 @@ static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd)
if (!PageDirty(page) ||
(PageWriteback(page) &&
(mpd->wbc->sync_mode == WB_SYNC_NONE)) ||
- unlikely(page->mapping != mapping)) {
+ unlikely(page_mapping(page) != mapping)) {
unlock_page(page);
continue;
}
@@ -2572,8 +2583,9 @@ static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd)
BUG_ON(PageWriteback(page));
if (mpd->map.m_len == 0)
- mpd->first_page = page->index;
- mpd->next_page = page->index + 1;
+ mpd->first_page = page_to_pgoff(page);
+ mpd->next_page = round_up(mpd->first_page + 1,
+ hpage_nr_pages(compound_head(page)));
/* Add all dirty buffers to mpd */
lblk = ((ext4_lblk_t)page->index) <<
(PAGE_SHIFT - blkbits);
--
2.8.1
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