On 4/26/25 02:08, Joanne Koong wrote:
> Currently, all folios associated with fuse are one page size. As part of
> the work to enable large folios, this commit adds support for copying
> to/from folios larger than one page size.
>
> Signed-off-by: Joanne Koong <joannelkoong@xxxxxxxxx>
> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Reviewed-by: Bernd Schubert <bschubert@xxxxxxx>
> ---
> fs/fuse/dev.c | 84 +++++++++++++++++++-------------------------
> fs/fuse/fuse_dev_i.h | 2 +-
> 2 files changed, 37 insertions(+), 49 deletions(-)
>
> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
> index 155bb6aeaef5..7b0e3a394480 100644
> --- a/fs/fuse/dev.c
> +++ b/fs/fuse/dev.c
> @@ -955,10 +955,10 @@ static int fuse_check_folio(struct folio *folio)
> * folio that was originally in @pagep will lose a reference and the new
> * folio returned in @pagep will carry a reference.
> */
> -static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
> +static int fuse_try_move_folio(struct fuse_copy_state *cs, struct folio **foliop)
> {
> int err;
> - struct folio *oldfolio = page_folio(*pagep);
> + struct folio *oldfolio = *foliop;
> struct folio *newfolio;
> struct pipe_buffer *buf = cs->pipebufs;
>
> @@ -979,7 +979,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
> cs->pipebufs++;
> cs->nr_segs--;
>
> - if (cs->len != PAGE_SIZE)
> + if (cs->len != folio_size(oldfolio))
> goto out_fallback;
>
> if (!pipe_buf_try_steal(cs->pipe, buf))
> @@ -1025,7 +1025,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
> if (test_bit(FR_ABORTED, &cs->req->flags))
> err = -ENOENT;
> else
> - *pagep = &newfolio->page;
> + *foliop = newfolio;
> spin_unlock(&cs->req->waitq.lock);
>
> if (err) {
> @@ -1058,8 +1058,8 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
> goto out_put_old;
> }
>
> -static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
> - unsigned offset, unsigned count)
> +static int fuse_ref_folio(struct fuse_copy_state *cs, struct folio *folio,
> + unsigned offset, unsigned count)
> {
> struct pipe_buffer *buf;
> int err;
> @@ -1067,17 +1067,17 @@ static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
> if (cs->nr_segs >= cs->pipe->max_usage)
> return -EIO;
>
> - get_page(page);
> + folio_get(folio);
> err = unlock_request(cs->req);
> if (err) {
> - put_page(page);
> + folio_put(folio);
> return err;
> }
>
> fuse_copy_finish(cs);
>
> buf = cs->pipebufs;
> - buf->page = page;
> + buf->page = &folio->page;
> buf->offset = offset;
> buf->len = count;
>
> @@ -1089,20 +1089,21 @@ static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
> }
>
> /*
> - * Copy a page in the request to/from the userspace buffer. Must be
> + * Copy a folio in the request to/from the userspace buffer. Must be
> * done atomically
> */
> -static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
> - unsigned offset, unsigned count, int zeroing)
> +static int fuse_copy_folio(struct fuse_copy_state *cs, struct folio **foliop,
> + unsigned offset, unsigned count, int zeroing)
> {
> int err;
> - struct page *page = *pagep;
> + struct folio *folio = *foliop;
> + size_t size = folio_size(folio);
>
> - if (page && zeroing && count < PAGE_SIZE)
> - clear_highpage(page);
> + if (folio && zeroing && count < size)
> + folio_zero_range(folio, 0, size);
>
> while (count) {
> - if (cs->write && cs->pipebufs && page) {
> + if (cs->write && cs->pipebufs && folio) {
> /*
> * Can't control lifetime of pipe buffers, so always
> * copy user pages.
> @@ -1112,12 +1113,12 @@ static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
> if (err)
> return err;
> } else {
> - return fuse_ref_page(cs, page, offset, count);
> + return fuse_ref_folio(cs, folio, offset, count);
> }
> } else if (!cs->len) {
> - if (cs->move_pages && page &&
> - offset == 0 && count == PAGE_SIZE) {
> - err = fuse_try_move_page(cs, pagep);
> + if (cs->move_folios && folio &&
> + offset == 0 && count == folio_size(folio)) {
> + err = fuse_try_move_folio(cs, foliop);
> if (err <= 0)
> return err;
> } else {
> @@ -1126,22 +1127,22 @@ static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
> return err;
> }
> }
> - if (page) {
> - void *mapaddr = kmap_local_page(page);
> - void *buf = mapaddr + offset;
> + if (folio) {
> + void *mapaddr = kmap_local_folio(folio, offset);
> + void *buf = mapaddr;
> offset += fuse_copy_do(cs, &buf, &count);
> kunmap_local(mapaddr);
> } else
> offset += fuse_copy_do(cs, NULL, &count);
> }
> - if (page && !cs->write)
> - flush_dcache_page(page);
> + if (folio && !cs->write)
> + flush_dcache_folio(folio);
> return 0;
> }
>
> -/* Copy pages in the request to/from userspace buffer */
> -static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
> - int zeroing)
> +/* Copy folios in the request to/from userspace buffer */
> +static int fuse_copy_folios(struct fuse_copy_state *cs, unsigned nbytes,
> + int zeroing)
> {
> unsigned i;
> struct fuse_req *req = cs->req;
> @@ -1151,23 +1152,12 @@ static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
> int err;
> unsigned int offset = ap->descs[i].offset;
> unsigned int count = min(nbytes, ap->descs[i].length);
> - struct page *orig, *pagep;
> -
> - orig = pagep = &ap->folios[i]->page;
>
> - err = fuse_copy_page(cs, &pagep, offset, count, zeroing);
> + err = fuse_copy_folio(cs, &ap->folios[i], offset, count, zeroing);
> if (err)
> return err;
>
> nbytes -= count;
> -
> - /*
> - * fuse_copy_page may have moved a page from a pipe instead of
> - * copying into our given page, so update the folios if it was
> - * replaced.
> - */
> - if (pagep != orig)
> - ap->folios[i] = page_folio(pagep);
> }
> return 0;
> }
> @@ -1197,7 +1187,7 @@ int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
> for (i = 0; !err && i < numargs; i++) {
> struct fuse_arg *arg = &args[i];
> if (i == numargs - 1 && argpages)
> - err = fuse_copy_pages(cs, arg->size, zeroing);
> + err = fuse_copy_folios(cs, arg->size, zeroing);
> else
> err = fuse_copy_one(cs, arg->value, arg->size);
> }
> @@ -1786,7 +1776,6 @@ static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
> num = outarg.size;
> while (num) {
> struct folio *folio;
> - struct page *page;
> unsigned int this_num;
>
> folio = filemap_grab_folio(mapping, index);
> @@ -1794,9 +1783,8 @@ static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
> if (IS_ERR(folio))
> goto out_iput;
>
> - page = &folio->page;
> this_num = min_t(unsigned, num, folio_size(folio) - offset);
> - err = fuse_copy_page(cs, &page, offset, this_num, 0);
> + err = fuse_copy_folio(cs, &folio, offset, this_num, 0);
> if (!folio_test_uptodate(folio) && !err && offset == 0 &&
> (this_num == folio_size(folio) || file_size == end)) {
> folio_zero_segment(folio, this_num, folio_size(folio));
> @@ -2037,8 +2025,8 @@ static int fuse_notify_inc_epoch(struct fuse_conn *fc)
> static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code,
> unsigned int size, struct fuse_copy_state *cs)
> {
> - /* Don't try to move pages (yet) */
> - cs->move_pages = false;
> + /* Don't try to move folios (yet) */
> + cs->move_folios = false;
>
> switch (code) {
> case FUSE_NOTIFY_POLL:
> @@ -2189,7 +2177,7 @@ static ssize_t fuse_dev_do_write(struct fuse_dev *fud,
> spin_unlock(&fpq->lock);
> cs->req = req;
> if (!req->args->page_replace)
> - cs->move_pages = false;
> + cs->move_folios = false;
>
> if (oh.error)
> err = nbytes != sizeof(oh) ? -EINVAL : 0;
> @@ -2307,7 +2295,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
> cs.pipe = pipe;
>
> if (flags & SPLICE_F_MOVE)
> - cs.move_pages = true;
> + cs.move_folios = true;
>
> ret = fuse_dev_do_write(fud, &cs, len);
>
> diff --git a/fs/fuse/fuse_dev_i.h b/fs/fuse/fuse_dev_i.h
> index db136e045925..5a9bd771a319 100644
> --- a/fs/fuse/fuse_dev_i.h
> +++ b/fs/fuse/fuse_dev_i.h
> @@ -30,7 +30,7 @@ struct fuse_copy_state {
> unsigned int len;
> unsigned int offset;
> bool write:1;
> - bool move_pages:1;
> + bool move_folios:1;
> bool is_uring:1;
> struct {
> unsigned int copied_sz; /* copied size into the user buffer */
