diff mbox series

[v3,6/8] NFS: stash the readdir pagecache cursor on the open directory context

Message ID 19ef38cda6b0eb6548c65c2bff7a4d4dd1baa122.1645623510.git.bcodding@redhat.com (mailing list archive)
State New, archived
Headers show
Series [v3,1/8] NFS: save the directory's change attribute on pagecache pages | expand

Commit Message

Benjamin Coddington Feb. 23, 2022, 1:40 p.m. UTC 
Now that we have per-page cache validation, we can allow filling of the
pagecache from arbitrary offsets.  Store the pagecache cursor on the open
directory context so it can be used to validate our entries the next time
we enter nfs_readdir() without having to fill the pagecache from the
beginning.

The open_directory_context's dir_cookie and index_cookie will store the
same value between calls to nfs_readdir(), so we can save a little room in
the struct by dropping dir_cookie.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 fs/nfs/dir.c           | 13 +++++++------
 include/linux/nfs_fs.h |  2 +-
 2 files changed, 8 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index ba75a9593dae..4f4a139f3181 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -395,7 +395,8 @@  nfs_readdir_page_valid(struct page *page, unsigned int entry_index, u64 index_co
 	ret = true;
 	array = kmap_atomic(page);
 
-	if (array->size == 0 && array->last_cookie == index_cookie)
+	if ((array->size == 0 || array->size == entry_index)
+		&& array->last_cookie == index_cookie)
 		goto out_unmap;
 
 	if (array->size > entry_index &&
@@ -1102,7 +1103,6 @@  static int readdir_search_pagecache(struct nfs_readdir_descriptor *desc)
 		if (desc->pgc.page_index == 0) {
 			desc->current_index = 0;
 			desc->prev_index = 0;
-			desc->pgc.index_cookie = 0;
 		}
 		res = find_and_lock_cache_page(desc);
 	} while (res == -EAGAIN);
@@ -1279,7 +1279,8 @@  static int nfs_readdir(struct file *file, struct dir_context *ctx)
 	desc->page_index_max = -1;
 
 	spin_lock(&file->f_lock);
-	desc->dir_cookie = dir_ctx->dir_cookie;
+	desc->dir_cookie = dir_ctx->pgc.index_cookie;
+	desc->pgc = dir_ctx->pgc;
 	desc->dup_cookie = dir_ctx->dup_cookie;
 	desc->duped = dir_ctx->duped;
 	page_index = dir_ctx->page_index;
@@ -1336,7 +1337,7 @@  static int nfs_readdir(struct file *file, struct dir_context *ctx)
 	} while (!desc->eob && !desc->eof);
 
 	spin_lock(&file->f_lock);
-	dir_ctx->dir_cookie = desc->dir_cookie;
+	dir_ctx->pgc = desc->pgc;
 	dir_ctx->dup_cookie = desc->dup_cookie;
 	dir_ctx->duped = desc->duped;
 	dir_ctx->attr_gencount = desc->attr_gencount;
@@ -1382,9 +1383,9 @@  static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int whence)
 	if (offset != filp->f_pos) {
 		filp->f_pos = offset;
 		if (nfs_readdir_use_cookie(filp))
-			dir_ctx->dir_cookie = offset;
+			dir_ctx->pgc.index_cookie = offset;
 		else
-			dir_ctx->dir_cookie = 0;
+			dir_ctx->pgc.index_cookie = 0;
 		dir_ctx->page_fill_misses = 0;
 		if (offset == 0)
 			memset(dir_ctx->verf, 0, sizeof(dir_ctx->verf));
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 2f5ded282477..aaeaad4006a4 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -111,7 +111,7 @@  struct nfs_open_dir_context {
 	atomic_t cache_misses;
 	unsigned long attr_gencount;
 	__be32	verf[NFS_DIR_VERIFIER_SIZE];
-	__u64 dir_cookie;
+	struct nfs_dir_page_cursor pgc;
 	__u64 dup_cookie;
 	pgoff_t page_index;
 	unsigned int page_fill_misses;