Re: [PATCH v3 3/5] nfs: Introduce nfs_release_request_list helper

From: Christoph Hellwig

Date: Mon Jul 20 2026 - 05:15:38 EST


On Wed, Jul 15, 2026 at 02:35:38PM +0000, Pranjal Shrivastava wrote:
> Introduce a centralized helper, nfs_release_request_list, to handle
> the bulk release of nfs_page requests from a list.
>
> This serves as a preparatory step for two upcoming improvements:
>
> 1. Pin-Aware Cleanup: As we migrate to iov_iter_extract_* API,
> requests will hold pins (GUP) instead of standard references. The
> helper ensures that the correct unpinning logic gets applied
> consistently across all requests in a list.
>
> 2. Folio Support: In subsequent patches where nfs_page structures
> will cover multi-page folios, this helper provides a clean
> infrastructure to unlock these larger units of I/O in bulk during
> completion, similat to the pattern in bio_release_pages.
>
> Additionally, refactor nfs_read_sync_pgio_error() to utilize this new
> helper.
>
> Signed-off-by: Pranjal Shrivastava <praan@xxxxxxxxxx>
> ---
> fs/nfs/direct.c | 8 +-------
> fs/nfs/pagelist.c | 18 ++++++++++++++++++
> include/linux/nfs_page.h | 4 ++--
> 3 files changed, 21 insertions(+), 9 deletions(-)
>
> diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
> index 19792a38c924..96995736fac2 100644
> --- a/fs/nfs/direct.c
> +++ b/fs/nfs/direct.c
> @@ -314,13 +314,7 @@ static void nfs_direct_read_completion(struct nfs_pgio_header *hdr)
>
> static void nfs_read_sync_pgio_error(struct list_head *head, int error)
> {
> - struct nfs_page *req;
> -
> - while (!list_empty(head)) {
> - req = nfs_list_entry(head->next);
> - nfs_list_remove_request(req);
> - nfs_release_request(req);
> - }
> + nfs_release_request_list(head);
> }
>
> static void nfs_direct_pgio_init(struct nfs_pgio_header *hdr)
> diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
> index 7d51e10fe97a..569bac4faff7 100644
> --- a/fs/nfs/pagelist.c
> +++ b/fs/nfs/pagelist.c
> @@ -622,6 +622,24 @@ void nfs_release_request(struct nfs_page *req)
> }
> EXPORT_SYMBOL_GPL(nfs_release_request);
>
> +/*
> + * nfs_release_request_list - Release a list of NFS read/write requests
> + * @head: list of requests to release
> + *
> + * Removes each request from the list and drops it's refcount.
> + */
> +void nfs_release_request_list(struct list_head *head)
> +{
> + struct nfs_page *req;
> +
> + while (!list_empty(head)) {
> + req = nfs_list_entry(head->next);

req could/should be local here. Or you switch to list_first_or_null,
which some folks prefer.

> +extern void nfs_release_request(struct nfs_page *req);
> +extern void nfs_release_request_list(struct list_head *head);

Please drop the superflous externs for new code.