From: Mike Snitzer Date: Fri, 19 Sep 2025 14:36:28 +0000 (-0400) Subject: nfs/localio: refactor iocb initialization X-Git-Tag: v6.18-rc1~109^2~3 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=e43e9a3a3d6652047808d6fadff5c3703f5ce90d;p=thirdparty%2Flinux.git nfs/localio: refactor iocb initialization The goal of this commit's various refactoring is to have LOCALIO's per IO initialization occur in process context so that we don't get into a situation where IO fails to be issued from workqueue (e.g. due to lack of memory, etc). Better to have LOCALIO's iocb initialization fail early. There isn't immediate need but this commit makes it possible for LOCALIO to fallback to NFS pagelist code in process context to allow for immediate retry over RPC. Signed-off-by: Mike Snitzer Signed-off-by: Anna Schumaker --- diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c index 3b8fa75ce7cdb..150719d8ed8b0 100644 --- a/fs/nfs/localio.c +++ b/fs/nfs/localio.c @@ -36,6 +36,7 @@ struct nfs_local_kiocb { struct nfs_pgio_header *hdr; struct work_struct work; void (*aio_complete_work)(struct work_struct *); + struct iov_iter iter ____cacheline_aligned; struct nfsd_file *localio; }; @@ -411,13 +412,19 @@ nfs_local_pgio_done(struct nfs_pgio_header *hdr, long status) } } +static void +nfs_local_iocb_release(struct nfs_local_kiocb *iocb) +{ + nfs_local_file_put(iocb->localio); + nfs_local_iocb_free(iocb); +} + static void nfs_local_pgio_release(struct nfs_local_kiocb *iocb) { struct nfs_pgio_header *hdr = iocb->hdr; - nfs_local_file_put(iocb->localio); - nfs_local_iocb_free(iocb); + nfs_local_iocb_release(iocb); nfs_local_hdr_release(hdr, hdr->task.tk_ops); } @@ -483,18 +490,16 @@ static void nfs_local_call_read(struct work_struct *work) container_of(work, struct nfs_local_kiocb, work); struct file *filp = iocb->kiocb.ki_filp; const struct cred *save_cred; - struct iov_iter iter; ssize_t status; save_cred = override_creds(filp->f_cred); - nfs_local_iter_init(&iter, iocb, ITER_DEST); if (iocb->kiocb.ki_flags & IOCB_DIRECT) { iocb->kiocb.ki_complete = nfs_local_read_aio_complete; iocb->aio_complete_work = nfs_local_read_aio_complete_work; } - status = filp->f_op->read_iter(&iocb->kiocb, &iter); + status = filp->f_op->read_iter(&iocb->kiocb, &iocb->iter); revert_creds(save_cred); @@ -505,25 +510,14 @@ static void nfs_local_call_read(struct work_struct *work) } static int -nfs_do_local_read(struct nfs_pgio_header *hdr, - struct nfsd_file *localio, +nfs_local_do_read(struct nfs_local_kiocb *iocb, const struct rpc_call_ops *call_ops) { - struct nfs_local_kiocb *iocb; - struct file *file = nfs_to->nfsd_file_file(localio); - - /* Don't support filesystems without read_iter */ - if (!file->f_op->read_iter) - return -EAGAIN; + struct nfs_pgio_header *hdr = iocb->hdr; dprintk("%s: vfs_read count=%u pos=%llu\n", __func__, hdr->args.count, hdr->args.offset); - iocb = nfs_local_iocb_alloc(hdr, file, GFP_KERNEL); - if (iocb == NULL) - return -ENOMEM; - iocb->localio = localio; - nfs_local_pgio_init(hdr, call_ops); hdr->res.eof = false; @@ -680,20 +674,18 @@ static void nfs_local_call_write(struct work_struct *work) struct file *filp = iocb->kiocb.ki_filp; unsigned long old_flags = current->flags; const struct cred *save_cred; - struct iov_iter iter; ssize_t status; current->flags |= PF_LOCAL_THROTTLE | PF_MEMALLOC_NOIO; save_cred = override_creds(filp->f_cred); - nfs_local_iter_init(&iter, iocb, ITER_SOURCE); if (iocb->kiocb.ki_flags & IOCB_DIRECT) { iocb->kiocb.ki_complete = nfs_local_write_aio_complete; iocb->aio_complete_work = nfs_local_write_aio_complete_work; } file_start_write(filp); - status = filp->f_op->write_iter(&iocb->kiocb, &iter); + status = filp->f_op->write_iter(&iocb->kiocb, &iocb->iter); file_end_write(filp); revert_creds(save_cred); @@ -707,26 +699,15 @@ static void nfs_local_call_write(struct work_struct *work) } static int -nfs_do_local_write(struct nfs_pgio_header *hdr, - struct nfsd_file *localio, +nfs_local_do_write(struct nfs_local_kiocb *iocb, const struct rpc_call_ops *call_ops) { - struct nfs_local_kiocb *iocb; - struct file *file = nfs_to->nfsd_file_file(localio); - - /* Don't support filesystems without write_iter */ - if (!file->f_op->write_iter) - return -EAGAIN; + struct nfs_pgio_header *hdr = iocb->hdr; dprintk("%s: vfs_write count=%u pos=%llu %s\n", __func__, hdr->args.count, hdr->args.offset, (hdr->args.stable == NFS_UNSTABLE) ? "unstable" : "stable"); - iocb = nfs_local_iocb_alloc(hdr, file, GFP_NOIO); - if (iocb == NULL) - return -ENOMEM; - iocb->localio = localio; - switch (hdr->args.stable) { default: break; @@ -747,32 +728,68 @@ nfs_do_local_write(struct nfs_pgio_header *hdr, return 0; } +static struct nfs_local_kiocb * +nfs_local_iocb_init(struct nfs_pgio_header *hdr, struct nfsd_file *localio) +{ + struct file *file = nfs_to->nfsd_file_file(localio); + struct nfs_local_kiocb *iocb; + gfp_t gfp_mask; + int rw; + + if (hdr->rw_mode & FMODE_READ) { + if (!file->f_op->read_iter) + return ERR_PTR(-EOPNOTSUPP); + gfp_mask = GFP_KERNEL; + rw = ITER_DEST; + } else { + if (!file->f_op->write_iter) + return ERR_PTR(-EOPNOTSUPP); + gfp_mask = GFP_NOIO; + rw = ITER_SOURCE; + } + + iocb = nfs_local_iocb_alloc(hdr, file, gfp_mask); + if (iocb == NULL) + return ERR_PTR(-ENOMEM); + iocb->hdr = hdr; + iocb->localio = localio; + + nfs_local_iter_init(&iocb->iter, iocb, rw); + + return iocb; +} + int nfs_local_doio(struct nfs_client *clp, struct nfsd_file *localio, struct nfs_pgio_header *hdr, const struct rpc_call_ops *call_ops) { + struct nfs_local_kiocb *iocb; int status = 0; if (!hdr->args.count) return 0; + iocb = nfs_local_iocb_init(hdr, localio); + if (IS_ERR(iocb)) + return PTR_ERR(iocb); + switch (hdr->rw_mode) { case FMODE_READ: - status = nfs_do_local_read(hdr, localio, call_ops); + status = nfs_local_do_read(iocb, call_ops); break; case FMODE_WRITE: - status = nfs_do_local_write(hdr, localio, call_ops); + status = nfs_local_do_write(iocb, call_ops); break; default: dprintk("%s: invalid mode: %d\n", __func__, hdr->rw_mode); - status = -EINVAL; + status = -EOPNOTSUPP; } if (status != 0) { if (status == -EAGAIN) nfs_localio_disable_client(clp); - nfs_local_file_put(localio); + nfs_local_iocb_release(iocb); hdr->task.tk_status = status; nfs_local_hdr_release(hdr, call_ops); }