Re: [PATCH v3 9/9] smb: client: apply rasize on remount

[Meetakshi Setiya]

Reviewed-by: Meetakshi Setiya <msetiya@xxxxxxxxxxxxx>

On Thu, May 21, 2026 at 7:07 AM <rajasimandalos@xxxxxxxxx> wrote:
>
> From: Rajasi Mandal <rajasimandal@xxxxxxxxxxxxx>
>
> rasize is accepted during remount parsing but sb->s_bdi->ra_pages is
> only set in cifs_read_super() at mount time. A remount with a new
> rasize value silently has no effect on the readahead window.
>
> Update ra_pages in smb3_reconfigure() after the context has been
> duplicated, using the same logic as cifs_read_super(): if rasize is
> set, use it directly; otherwise fall back to 2 * rsize.
>
> Signed-off-by: Rajasi Mandal <rajasimandal@xxxxxxxxxxxxx>
> ---
>  fs/smb/client/fs_context.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c
> index 0ef8ccd53882..1b42af418f77 100644
> --- a/fs/smb/client/fs_context.c
> +++ b/fs/smb/client/fs_context.c
> @@ -1367,7 +1367,7 @@ static int smb3_reconfigure(struct fs_context *fc)
>         struct dentry *root = fc->root;
>         struct cifs_sb_info *cifs_sb = CIFS_SB(root->d_sb);
>         struct cifs_ses *ses = cifs_sb_master_tcon(cifs_sb)->ses;
> -       unsigned int rsize = ctx->rsize, wsize = ctx->wsize;
> +       unsigned int rsize = ctx->rsize, wsize = ctx->wsize, rasize = ctx->rasize;
>         char *new_password = NULL, *new_password2 = NULL;
>         bool need_recon = false;
>         bool need_mchan_update;
> @@ -1431,9 +1431,10 @@ static int smb3_reconfigure(struct fs_context *fc)
>                 STEAL_STRING_SENSITIVE(cifs_sb, ctx, password2);
>         }
>
> -       /* if rsize or wsize not passed in on remount, use previous values */
> +       /* if rsize, wsize, or rasize not passed in on remount, use previous values */
>         ctx->rsize = rsize ? CIFS_ALIGN_RSIZE(fc, rsize) : cifs_sb->ctx->rsize;
>         ctx->wsize = wsize ? CIFS_ALIGN_WSIZE(fc, wsize) : cifs_sb->ctx->wsize;
> +       ctx->rasize = rasize ? rasize : cifs_sb->ctx->rasize;
>
>         new_ctx = kzalloc_obj(*new_ctx);
>         if (!new_ctx) {
> @@ -1522,6 +1523,12 @@ static int smb3_reconfigure(struct fs_context *fc)
>         smb3_cleanup_fs_context(old_ctx);
>         old_ctx = NULL;
>         smb3_update_mnt_flags(cifs_sb);
> +
> +       if (cifs_sb->ctx->rasize)
> +               root->d_sb->s_bdi->ra_pages = cifs_sb->ctx->rasize / PAGE_SIZE;
> +       else
> +               root->d_sb->s_bdi->ra_pages = 2 * (cifs_sb->ctx->rsize / PAGE_SIZE);
> +
>  #ifdef CONFIG_CIFS_DFS_UPCALL
>         if (!rc)
>                 rc = dfs_cache_remount_fs(cifs_sb);
> --
> 2.43.0
>