[PATCH v3 2/7] btrfs: Convert __process_pages_contig() to use filemap_get_folios_contig()

Vishal Moola (Oracle)
2022-08-24T00:42:54Z

Convert to use folios throughout. This is in preparation for the removal of
find_get_pages_contig(). Now also supports large folios.

Since we may receive more than nr_pages pages, nr_pages may underflow.
Since nr_pages > 0 is equivalent to index <= end_index, we replaced it
with this check instead.

Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
---
fs/btrfs/extent_io.c | 33 +++++++++++++++------------------
1 file changed, 15 insertions(+), 18 deletions(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 8f6b544ae616..f16929bc531b 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1882,9 +1882,8 @@ static int __process_pages_contig(struct address_space *mapping,
pgoff_t start_index = start >> PAGE_SHIFT;
pgoff_t end_index = end >> PAGE_SHIFT;
pgoff_t index = start_index;
- unsigned long nr_pages = end_index - start_index + 1;
unsigned long pages_processed = 0;
- struct page *pages[16];
+ struct folio_batch fbatch;
int err = 0;
int i;

@@ -1893,16 +1892,17 @@ static int __process_pages_contig(struct address_space *mapping,
ASSERT(processed_end && *processed_end == start);
}

- if ((page_ops & PAGE_SET_ERROR) && nr_pages > 0)
+ if ((page_ops & PAGE_SET_ERROR) && start_index <= end_index)
mapping_set_error(mapping, -EIO);

- while (nr_pages > 0) {
- int found_pages;
+ folio_batch_init(&fbatch);
+ while (index <= end_index) {
+ int found_folios;
+
+ found_folios = filemap_get_folios_contig(mapping, &index,
+ end_index, &fbatch);

- found_pages = find_get_pages_contig(mapping, index,
- min_t(unsigned long,
- nr_pages, ARRAY_SIZE(pages)), pages);
- if (found_pages == 0) {
+ if (found_folios == 0) {
/*
* Only if we're going to lock these pages, we can find
* nothing at @index.
@@ -1912,23 +1912,20 @@ static int __process_pages_contig(struct address_space *mapping,
goto out;
}

- for (i = 0; i < found_pages; i++) {
+ for (i = 0; i < found_folios; i++) {
int process_ret;
-
+ struct folio *folio = fbatch.folios[i];
process_ret = process_one_page(fs_info, mapping,
- pages[i], locked_page, page_ops,
+ &folio->page, locked_page, page_ops,
start, end);
if (process_ret < 0) {
- for (; i < found_pages; i++)
- put_page(pages[i]);
err = -EAGAIN;
+ folio_batch_release(&fbatch);
goto out;
}
- put_page(pages[i]);
- pages_processed++;
+ pages_processed += folio_nr_pages(folio);
}
- nr_pages -= found_pages;
- index += found_pages;
+ folio_batch_release(&fbatch);
cond_resched();
}
out:
--
2.36.1