[PATCH v2 04/12] fuse: support large folios for writethrough writes

Joanne Koong
2024-11-25T22:06:02Z

Add support for folios larger than one page size for writethrough
writes.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
---
fs/fuse/file.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index a89fdc55a40b..fab7cfa8700b 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1135,6 +1135,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia,
struct iov_iter *ii, loff_t pos,
unsigned int max_pages)
{
+ size_t max_folio_size = mapping_max_folio_size(mapping);
struct fuse_args_pages *ap = &ia->ap;
struct fuse_conn *fc = get_fuse_conn(mapping->host);
unsigned offset = pos & (PAGE_SIZE - 1);
@@ -1146,17 +1147,17 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia,
num = min(num, max_pages << PAGE_SHIFT);

ap->args.in_pages = true;
- ap->descs[0].offset = offset;

while (num) {
size_t tmp;
struct folio *folio;
pgoff_t index = pos >> PAGE_SHIFT;
- unsigned int bytes = min(PAGE_SIZE - offset, num);
+ unsigned int bytes;
+ unsigned int folio_offset;

again:
err = -EFAULT;
- if (fault_in_iov_iter_readable(ii, bytes))
+ if (fault_in_iov_iter_readable(ii, max_folio_size) == max_folio_size)
break;

folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
@@ -1169,7 +1170,10 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia,
if (mapping_writably_mapped(mapping))
flush_dcache_folio(folio);

- tmp = copy_folio_from_iter_atomic(folio, offset, bytes, ii);
+ folio_offset = ((index - folio->index) << PAGE_SHIFT) + offset;
+ bytes = min(folio_size(folio) - folio_offset, num);
+
+ tmp = copy_folio_from_iter_atomic(folio, folio_offset, bytes, ii);
flush_dcache_folio(folio);

if (!tmp) {
@@ -1180,6 +1184,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia,

err = 0;
ap->folios[ap->num_folios] = folio;
+ ap->descs[ap->num_folios].offset = folio_offset;
ap->descs[ap->num_folios].length = tmp;
ap->num_folios++;

@@ -1187,11 +1192,11 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia,
pos += tmp;
num -= tmp;
offset += tmp;
- if (offset == PAGE_SIZE)
+ if (offset == folio_size(folio))
offset = 0;

- /* If we copied full page, mark it uptodate */
- if (tmp == PAGE_SIZE)
+ /* If we copied full folio, mark it uptodate */
+ if (tmp == folio_size(folio))
folio_mark_uptodate(folio);

if (folio_test_uptodate(folio)) {
--
2.43.5