From a308996ed7c02d1cd6504ce73436ef3f1c1c75c0 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 11 Jul 2024 09:17:03 +0200 Subject: [PATCH] nfs: split nfs_read_folio nfs_read_folio is a bit hard to follow because it mixes highlevel logic with the actual data read. Split the latter into a helper and update the comments to be more accurate. Signed-off-by: Christoph Hellwig Signed-off-by: Anna Schumaker --- fs/nfs/read.c | 69 ++++++++++++++++++++++++++++++--------------------- 1 file changed, 41 insertions(+), 28 deletions(-) diff --git a/fs/nfs/read.c b/fs/nfs/read.c index 6fee86a2eb42..77fa5458b4bd 100644 --- a/fs/nfs/read.c +++ b/fs/nfs/read.c @@ -325,18 +325,52 @@ out: } /* - * Read a page over NFS. - * We read the page synchronously in the following case: - * - The error flag is set for this page. This happens only when a - * previous async read operation failed. + * Actually read a folio over the wire. + */ +static int nfs_do_read_folio(struct file *file, struct folio *folio) +{ + struct inode *inode = file_inode(file); + struct nfs_pageio_descriptor pgio; + struct nfs_open_context *ctx; + int ret; + + ctx = get_nfs_open_context(nfs_file_open_context(file)); + + xchg(&ctx->error, 0); + nfs_pageio_init_read(&pgio, inode, false, + &nfs_async_read_completion_ops); + + ret = nfs_read_add_folio(&pgio, ctx, folio); + if (ret) + goto out_put; + + nfs_pageio_complete_read(&pgio); + nfs_update_delegated_atime(inode); + if (pgio.pg_error < 0) { + ret = pgio.pg_error; + goto out_put; + } + + ret = folio_wait_locked_killable(folio); + if (!folio_test_uptodate(folio) && !ret) + ret = xchg(&ctx->error, 0); + +out_put: + put_nfs_open_context(ctx); + return ret; +} + +/* + * Synchronously read a folio. + * + * This is not heavily used as most users to try an asynchronous + * large read through ->readahead first. */ int nfs_read_folio(struct file *file, struct folio *folio) { struct inode *inode = file_inode(file); loff_t pos = folio_pos(folio); size_t len = folio_size(folio); - struct nfs_pageio_descriptor pgio; - struct nfs_open_context *ctx; int ret; trace_nfs_aop_readpage(inode, pos, len); @@ -361,29 +395,8 @@ int nfs_read_folio(struct file *file, struct folio *folio) goto out_unlock; ret = nfs_netfs_read_folio(file, folio); - if (!ret) - goto out; - - ctx = get_nfs_open_context(nfs_file_open_context(file)); - - xchg(&ctx->error, 0); - nfs_pageio_init_read(&pgio, inode, false, - &nfs_async_read_completion_ops); - - ret = nfs_read_add_folio(&pgio, ctx, folio); if (ret) - goto out_put; - - nfs_pageio_complete_read(&pgio); - nfs_update_delegated_atime(inode); - ret = pgio.pg_error < 0 ? pgio.pg_error : 0; - if (!ret) { - ret = folio_wait_locked_killable(folio); - if (!folio_test_uptodate(folio) && !ret) - ret = xchg(&ctx->error, 0); - } -out_put: - put_nfs_open_context(ctx); + ret = nfs_do_read_folio(file, folio); out: trace_nfs_aop_readpage_done(inode, pos, len, ret); return ret; -- 2.25.1