NFS Client Updates for Linux 6.4

New Features:
   * Convert the readdir path to use folios
   * Convert the NFS fscache code to use netfs
 
 Bugfixes and Cleanups:
   * Always send a RECLAIM_COMPLETE after establishing a lease
   * Simplify sysctl registrations and other cleanups
   * Handle out-of-order write replies on NFS v3
   * Have sunrpc call_bind_status use standard hard/soft task semantics
   * Other minor cleanups
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Merge tag 'nfs-for-6.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client updates from Anna Schumaker:
 "New Features:

   - Convert the readdir path to use folios

   - Convert the NFS fscache code to use netfs

  Bugfixes and Cleanups:

   - Always send a RECLAIM_COMPLETE after establishing a lease

   - Simplify sysctl registrations and other cleanups

   - Handle out-of-order write replies on NFS v3

   - Have sunrpc call_bind_status use standard hard/soft task semantics

   - Other minor cleanups"

* tag 'nfs-for-6.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFSv4.2: Rework scratch handling for READ_PLUS
  NFS: Cleanup unused rpc_clnt variable
  NFS: set varaiable nfs_netfs_debug_id storage-class-specifier to static
  SUNRPC: remove the maximum number of retries in call_bind_status
  NFS: Convert readdir page array functions to use a folio
  NFS: Convert the readdir array-of-pages into an array-of-folios
  NFSv3: handle out-of-order write replies.
  NFS: Remove fscache specific trace points and NFS_INO_FSCACHE bit
  NFS: Remove all NFSIOS_FSCACHE counters due to conversion to netfs API
  NFS: Convert buffered read paths to use netfs when fscache is enabled
  NFS: Configure support for netfs when NFS fscache is configured
  NFS: Rename readpage_async_filler to nfs_read_add_folio
  sunrpc: simplify one-level sysctl registration for debug_table
  sunrpc: move sunrpc_table and proc routines above
  sunrpc: simplify one-level sysctl registration for xs_tunables_table
  sunrpc: simplify one-level sysctl registration for xr_tunables_table
  nfs: simplify two-level sysctl registration for nfs_cb_sysctls
  nfs: simplify two-level sysctl registration for nfs4_cb_sysctls
  lockd: simplify two-level sysctl registration for nlm_sysctls
  NFSv4.1: Always send a RECLAIM_COMPLETE after establishing lease

fs/nfs/Kconfig

@@ -170,6 +170,7 @@ config ROOT_NFS
 config NFS_FSCACHE
 	bool "Provide NFS client caching support"
 	depends on NFS_FS=m && FSCACHE || NFS_FS=y && FSCACHE=y
+	select NETFS_SUPPORT
 	help
 	  Say Y here if you want NFS data to be cached locally on disc through
 	  the general filesystem cache manager

fs/nfs/dir.c

@@ -55,7 +55,7 @@ static int nfs_closedir(struct inode *, struct file *);
 static int nfs_readdir(struct file *, struct dir_context *);
 static int nfs_fsync_dir(struct file *, loff_t, loff_t, int);
 static loff_t nfs_llseek_dir(struct file *, loff_t, int);
-static void nfs_readdir_free_folio(struct folio *);
+static void nfs_readdir_clear_array(struct folio *);
 
 const struct file_operations nfs_dir_operations = {
 	.llseek		= nfs_llseek_dir,
@@ -67,7 +67,7 @@ const struct file_operations nfs_dir_operations = {
 };
 
 const struct address_space_operations nfs_dir_aops = {
-	.free_folio = nfs_readdir_free_folio,
+	.free_folio = nfs_readdir_clear_array,
 };
 
 #define NFS_INIT_DTSIZE PAGE_SIZE
@@ -146,18 +146,18 @@ struct nfs_cache_array {
 	u64 change_attr;
 	u64 last_cookie;
 	unsigned int size;
-	unsigned char page_full : 1,
+	unsigned char folio_full : 1,
-		      page_is_eof : 1,
+		      folio_is_eof : 1,
 		      cookies_are_ordered : 1;
 	struct nfs_cache_array_entry array[];
 };
 
 struct nfs_readdir_descriptor {
 	struct file	*file;
-	struct page	*page;
+	struct folio	*folio;
 	struct dir_context *ctx;
-	pgoff_t		page_index;
+	pgoff_t		folio_index;
-	pgoff_t		page_index_max;
+	pgoff_t		folio_index_max;
 	u64		dir_cookie;
 	u64		last_cookie;
 	loff_t		current_index;
@@ -198,17 +198,17 @@ static void nfs_grow_dtsize(struct nfs_readdir_descriptor *desc)
 	nfs_set_dtsize(desc, desc->dtsize << 1);
 }
 
-static void nfs_readdir_page_init_array(struct page *page, u64 last_cookie,
+static void nfs_readdir_folio_init_array(struct folio *folio, u64 last_cookie,
-					u64 change_attr)
+					 u64 change_attr)
 {
 	struct nfs_cache_array *array;
 
-	array = kmap_local_page(page);
+	array = kmap_local_folio(folio, 0);
 	array->change_attr = change_attr;
 	array->last_cookie = last_cookie;
 	array->size = 0;
-	array->page_full = 0;
+	array->folio_full = 0;
-	array->page_is_eof = 0;
+	array->folio_is_eof = 0;
 	array->cookies_are_ordered = 1;
 	kunmap_local(array);
 }
@@ -216,44 +216,39 @@ static void nfs_readdir_page_init_array(struct page *page, u64 last_cookie,
 /*
  * we are freeing strings created by nfs_add_to_readdir_array()
  */
-static void nfs_readdir_clear_array(struct page *page)
+static void nfs_readdir_clear_array(struct folio *folio)
 {
 	struct nfs_cache_array *array;
 	unsigned int i;
 
-	array = kmap_local_page(page);
+	array = kmap_local_folio(folio, 0);
 	for (i = 0; i < array->size; i++)
 		kfree(array->array[i].name);
 	array->size = 0;
 	kunmap_local(array);
 }
 
-static void nfs_readdir_free_folio(struct folio *folio)
+static void nfs_readdir_folio_reinit_array(struct folio *folio, u64 last_cookie,
+					   u64 change_attr)
 {
-	nfs_readdir_clear_array(&folio->page);
+	nfs_readdir_clear_array(folio);
+	nfs_readdir_folio_init_array(folio, last_cookie, change_attr);
 }
 
-static void nfs_readdir_page_reinit_array(struct page *page, u64 last_cookie,
+static struct folio *
-					  u64 change_attr)
+nfs_readdir_folio_array_alloc(u64 last_cookie, gfp_t gfp_flags)
 {
-	nfs_readdir_clear_array(page);
+	struct folio *folio = folio_alloc(gfp_flags, 0);
-	nfs_readdir_page_init_array(page, last_cookie, change_attr);
+	if (folio)
+		nfs_readdir_folio_init_array(folio, last_cookie, 0);
+	return folio;
 }
 
-static struct page *
+static void nfs_readdir_folio_array_free(struct folio *folio)
-nfs_readdir_page_array_alloc(u64 last_cookie, gfp_t gfp_flags)
 {
-	struct page *page = alloc_page(gfp_flags);
+	if (folio) {
-	if (page)
+		nfs_readdir_clear_array(folio);
-		nfs_readdir_page_init_array(page, last_cookie, 0);
+		folio_put(folio);
-	return page;
-}
-
-static void nfs_readdir_page_array_free(struct page *page)
-{
-	if (page) {
-		nfs_readdir_clear_array(page);
-		put_page(page);
 	}
 }
 
@@ -264,13 +259,13 @@ static u64 nfs_readdir_array_index_cookie(struct nfs_cache_array *array)
 
 static void nfs_readdir_array_set_eof(struct nfs_cache_array *array)
 {
-	array->page_is_eof = 1;
+	array->folio_is_eof = 1;
-	array->page_full = 1;
+	array->folio_full = 1;
 }
 
 static bool nfs_readdir_array_is_full(struct nfs_cache_array *array)
 {
-	return array->page_full;
+	return array->folio_full;
 }
 
 /*
@@ -302,18 +297,18 @@ static size_t nfs_readdir_array_maxentries(void)
  */
 static int nfs_readdir_array_can_expand(struct nfs_cache_array *array)
 {
-	if (array->page_full)
+	if (array->folio_full)
 		return -ENOSPC;
 	if (array->size == nfs_readdir_array_maxentries()) {
-		array->page_full = 1;
+		array->folio_full = 1;
 		return -ENOSPC;
 	}
 	return 0;
 }
 
-static int nfs_readdir_page_array_append(struct page *page,
+static int nfs_readdir_folio_array_append(struct folio *folio,
-					 const struct nfs_entry *entry,
+					  const struct nfs_entry *entry,
-					 u64 *cookie)
+					  u64 *cookie)
 {
 	struct nfs_cache_array *array;
 	struct nfs_cache_array_entry *cache_entry;
@@ -322,7 +317,7 @@ static int nfs_readdir_page_array_append(struct page *page,
 
 	name = nfs_readdir_copy_name(entry->name, entry->len);
 
-	array = kmap_atomic(page);
+	array = kmap_atomic(folio_page(folio, 0));
 	if (!name)
 		goto out;
 	ret = nfs_readdir_array_can_expand(array);
@@ -361,17 +356,17 @@ out:
  * 127 readdir entries for a typical 64-bit system, that works out to a
  * cache of ~ 33 million entries per directory.
  */
-static pgoff_t nfs_readdir_page_cookie_hash(u64 cookie)
+static pgoff_t nfs_readdir_folio_cookie_hash(u64 cookie)
 {
 	if (cookie == 0)
 		return 0;
 	return hash_64(cookie, 18);
 }
 
-static bool nfs_readdir_page_validate(struct page *page, u64 last_cookie,
+static bool nfs_readdir_folio_validate(struct folio *folio, u64 last_cookie,
-				      u64 change_attr)
+				       u64 change_attr)
 {
-	struct nfs_cache_array *array = kmap_local_page(page);
+	struct nfs_cache_array *array = kmap_local_folio(folio, 0);
 	int ret = true;
 
 	if (array->change_attr != change_attr)
@@ -382,81 +377,83 @@ static bool nfs_readdir_page_validate(struct page *page, u64 last_cookie,
 	return ret;
 }
 
-static void nfs_readdir_page_unlock_and_put(struct page *page)
+static void nfs_readdir_folio_unlock_and_put(struct folio *folio)
 {
-	unlock_page(page);
+	folio_unlock(folio);
-	put_page(page);
+	folio_put(folio);
 }
 
-static void nfs_readdir_page_init_and_validate(struct page *page, u64 cookie,
+static void nfs_readdir_folio_init_and_validate(struct folio *folio, u64 cookie,
-					       u64 change_attr)
+						u64 change_attr)
 {
-	if (PageUptodate(page)) {
+	if (folio_test_uptodate(folio)) {
-		if (nfs_readdir_page_validate(page, cookie, change_attr))
+		if (nfs_readdir_folio_validate(folio, cookie, change_attr))
 			return;
-		nfs_readdir_clear_array(page);
+		nfs_readdir_clear_array(folio);
 	}
-	nfs_readdir_page_init_array(page, cookie, change_attr);
+	nfs_readdir_folio_init_array(folio, cookie, change_attr);
-	SetPageUptodate(page);
+	folio_mark_uptodate(folio);
 }
 
-static struct page *nfs_readdir_page_get_locked(struct address_space *mapping,
+static struct folio *nfs_readdir_folio_get_locked(struct address_space *mapping,
-						u64 cookie, u64 change_attr)
+						  u64 cookie, u64 change_attr)
 {
-	pgoff_t index = nfs_readdir_page_cookie_hash(cookie);
+	pgoff_t index = nfs_readdir_folio_cookie_hash(cookie);
-	struct page *page;
+	struct folio *folio;
 
-	page = grab_cache_page(mapping, index);
+	folio = filemap_grab_folio(mapping, index);
-	if (!page)
+	if (!folio)
 		return NULL;
-	nfs_readdir_page_init_and_validate(page, cookie, change_attr);
+	nfs_readdir_folio_init_and_validate(folio, cookie, change_attr);
-	return page;
+	return folio;
 }
 
-static u64 nfs_readdir_page_last_cookie(struct page *page)
+static u64 nfs_readdir_folio_last_cookie(struct folio *folio)
 {
 	struct nfs_cache_array *array;
 	u64 ret;
 
-	array = kmap_local_page(page);
+	array = kmap_local_folio(folio, 0);
 	ret = array->last_cookie;
 	kunmap_local(array);
 	return ret;
 }
 
-static bool nfs_readdir_page_needs_filling(struct page *page)
+static bool nfs_readdir_folio_needs_filling(struct folio *folio)
 {
 	struct nfs_cache_array *array;
 	bool ret;
 
-	array = kmap_local_page(page);
+	array = kmap_local_folio(folio, 0);
 	ret = !nfs_readdir_array_is_full(array);
 	kunmap_local(array);
 	return ret;
 }
 
-static void nfs_readdir_page_set_eof(struct page *page)
+static void nfs_readdir_folio_set_eof(struct folio *folio)
 {
 	struct nfs_cache_array *array;
 
-	array = kmap_local_page(page);
+	array = kmap_local_folio(folio, 0);
 	nfs_readdir_array_set_eof(array);
 	kunmap_local(array);
 }
 
-static struct page *nfs_readdir_page_get_next(struct address_space *mapping,
+static struct folio *nfs_readdir_folio_get_next(struct address_space *mapping,
-					      u64 cookie, u64 change_attr)
+						u64 cookie, u64 change_attr)
 {
-	pgoff_t index = nfs_readdir_page_cookie_hash(cookie);
+	pgoff_t index = nfs_readdir_folio_cookie_hash(cookie);
-	struct page *page;
+	struct folio *folio;
 
-	page = grab_cache_page_nowait(mapping, index);
+	folio = __filemap_get_folio(mapping, index,
-	if (!page)
+			FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
+			mapping_gfp_mask(mapping));
+	if (!folio)
 		return NULL;
-	nfs_readdir_page_init_and_validate(page, cookie, change_attr);
+	nfs_readdir_folio_init_and_validate(folio, cookie, change_attr);
-	if (nfs_readdir_page_last_cookie(page) != cookie)
+	if (nfs_readdir_folio_last_cookie(folio) != cookie)
-		nfs_readdir_page_reinit_array(page, cookie, change_attr);
+		nfs_readdir_folio_reinit_array(folio, cookie, change_attr);
-	return page;
+	return folio;
 }
 
 static inline
@@ -481,11 +478,11 @@ bool nfs_readdir_use_cookie(const struct file *filp)
 static void nfs_readdir_seek_next_array(struct nfs_cache_array *array,
 					struct nfs_readdir_descriptor *desc)
 {
-	if (array->page_full) {
+	if (array->folio_full) {
 		desc->last_cookie = array->last_cookie;
 		desc->current_index += array->size;
 		desc->cache_entry_index = 0;
-		desc->page_index++;
+		desc->folio_index++;
 	} else
 		desc->last_cookie = nfs_readdir_array_index_cookie(array);
 }
@@ -494,7 +491,7 @@ static void nfs_readdir_rewind_search(struct nfs_readdir_descriptor *desc)
 {
 	desc->current_index = 0;
 	desc->last_cookie = 0;
-	desc->page_index = 0;
+	desc->folio_index = 0;
 }
 
 static int nfs_readdir_search_for_pos(struct nfs_cache_array *array,
@@ -506,7 +503,7 @@ static int nfs_readdir_search_for_pos(struct nfs_cache_array *array,
 	if (diff < 0)
 		goto out_eof;
 	if (diff >= array->size) {
-		if (array->page_is_eof)
+		if (array->folio_is_eof)
 			goto out_eof;
 		nfs_readdir_seek_next_array(array, desc);
 		return -EAGAIN;
@@ -554,7 +551,7 @@ static int nfs_readdir_search_for_cookie(struct nfs_cache_array *array,
 		}
 	}
 check_eof:
-	if (array->page_is_eof) {
+	if (array->folio_is_eof) {
 		status = -EBADCOOKIE;
 		if (desc->dir_cookie == array->last_cookie)
 			desc->eof = true;
@@ -568,7 +565,7 @@ static int nfs_readdir_search_array(struct nfs_readdir_descriptor *desc)
 	struct nfs_cache_array *array;
 	int status;
 
-	array = kmap_local_page(desc->page);
+	array = kmap_local_folio(desc->folio, 0);
 
 	if (desc->dir_cookie == 0)
 		status = nfs_readdir_search_for_pos(array, desc);
@@ -819,16 +816,17 @@ static int nfs_readdir_entry_decode(struct nfs_readdir_descriptor *desc,
 }
 
 /* Perform conversion from xdr to cache array */
-static int nfs_readdir_page_filler(struct nfs_readdir_descriptor *desc,
+static int nfs_readdir_folio_filler(struct nfs_readdir_descriptor *desc,
-				   struct nfs_entry *entry,
+				    struct nfs_entry *entry,
-				   struct page **xdr_pages, unsigned int buflen,
+				    struct page **xdr_pages, unsigned int buflen,
-				   struct page **arrays, size_t narrays,
+				    struct folio **arrays, size_t narrays,
-				   u64 change_attr)
+				    u64 change_attr)
 {
 	struct address_space *mapping = desc->file->f_mapping;
+	struct folio *new, *folio = *arrays;
 	struct xdr_stream stream;
+	struct page *scratch;
 	struct xdr_buf buf;
-	struct page *scratch, *new, *page = *arrays;
 	u64 cookie;
 	int status;
 
@@ -844,36 +842,36 @@ static int nfs_readdir_page_filler(struct nfs_readdir_descriptor *desc,
 		if (status != 0)
 			break;
 
-		status = nfs_readdir_page_array_append(page, entry, &cookie);
+		status = nfs_readdir_folio_array_append(folio, entry, &cookie);
 		if (status != -ENOSPC)
 			continue;
 
-		if (page->mapping != mapping) {
+		if (folio->mapping != mapping) {
 			if (!--narrays)
 				break;
-			new = nfs_readdir_page_array_alloc(cookie, GFP_KERNEL);
+			new = nfs_readdir_folio_array_alloc(cookie, GFP_KERNEL);
 			if (!new)
 				break;
 			arrays++;
-			*arrays = page = new;
+			*arrays = folio = new;
 		} else {
-			new = nfs_readdir_page_get_next(mapping, cookie,
+			new = nfs_readdir_folio_get_next(mapping, cookie,
-							change_attr);
+							 change_attr);
 			if (!new)
 				break;
-			if (page != *arrays)
+			if (folio != *arrays)
-				nfs_readdir_page_unlock_and_put(page);
+				nfs_readdir_folio_unlock_and_put(folio);
-			page = new;
+			folio = new;
 		}
-		desc->page_index_max++;
+		desc->folio_index_max++;
-		status = nfs_readdir_page_array_append(page, entry, &cookie);
+		status = nfs_readdir_folio_array_append(folio, entry, &cookie);
 	} while (!status && !entry->eof);
 
 	switch (status) {
 	case -EBADCOOKIE:
 		if (!entry->eof)
 			break;
-		nfs_readdir_page_set_eof(page);
+		nfs_readdir_folio_set_eof(folio);
 		fallthrough;
 	case -EAGAIN:
 		status = 0;
@@ -886,8 +884,8 @@ static int nfs_readdir_page_filler(struct nfs_readdir_descriptor *desc,
 			;
 	}
 
-	if (page != *arrays)
+	if (folio != *arrays)
-		nfs_readdir_page_unlock_and_put(page);
+		nfs_readdir_folio_unlock_and_put(folio);
 
 	put_page(scratch);
 	return status;
@@ -927,11 +925,11 @@ out_freepages:
 
 static int nfs_readdir_xdr_to_array(struct nfs_readdir_descriptor *desc,
 				    __be32 *verf_arg, __be32 *verf_res,
-				    struct page **arrays, size_t narrays)
+				    struct folio **arrays, size_t narrays)
 {
 	u64 change_attr;
 	struct page **pages;
-	struct page *page = *arrays;
+	struct folio *folio = *arrays;
 	struct nfs_entry *entry;
 	size_t array_size;
 	struct inode *inode = file_inode(desc->file);
@@ -942,7 +940,7 @@ static int nfs_readdir_xdr_to_array(struct nfs_readdir_descriptor *desc,
 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 	if (!entry)
 		return -ENOMEM;
-	entry->cookie = nfs_readdir_page_last_cookie(page);
+	entry->cookie = nfs_readdir_folio_last_cookie(folio);
 	entry->fh = nfs_alloc_fhandle();
 	entry->fattr = nfs_alloc_fattr_with_label(NFS_SERVER(inode));
 	entry->server = NFS_SERVER(inode);
@@ -962,10 +960,10 @@ static int nfs_readdir_xdr_to_array(struct nfs_readdir_descriptor *desc,
 
 	pglen = status;
 	if (pglen != 0)
-		status = nfs_readdir_page_filler(desc, entry, pages, pglen,
+		status = nfs_readdir_folio_filler(desc, entry, pages, pglen,
-						 arrays, narrays, change_attr);
+						  arrays, narrays, change_attr);
 	else
-		nfs_readdir_page_set_eof(page);
+		nfs_readdir_folio_set_eof(folio);
 	desc->buffer_fills++;
 
 free_pages:
@@ -977,33 +975,33 @@ out:
 	return status;
 }
 
-static void nfs_readdir_page_put(struct nfs_readdir_descriptor *desc)
+static void nfs_readdir_folio_put(struct nfs_readdir_descriptor *desc)
 {
-	put_page(desc->page);
+	folio_put(desc->folio);
-	desc->page = NULL;
+	desc->folio = NULL;
 }
 
 static void
-nfs_readdir_page_unlock_and_put_cached(struct nfs_readdir_descriptor *desc)
+nfs_readdir_folio_unlock_and_put_cached(struct nfs_readdir_descriptor *desc)
 {
-	unlock_page(desc->page);
+	folio_unlock(desc->folio);
-	nfs_readdir_page_put(desc);
+	nfs_readdir_folio_put(desc);
 }
 
-static struct page *
+static struct folio *
-nfs_readdir_page_get_cached(struct nfs_readdir_descriptor *desc)
+nfs_readdir_folio_get_cached(struct nfs_readdir_descriptor *desc)
 {
 	struct address_space *mapping = desc->file->f_mapping;
 	u64 change_attr = inode_peek_iversion_raw(mapping->host);
 	u64 cookie = desc->last_cookie;
-	struct page *page;
+	struct folio *folio;
 
-	page = nfs_readdir_page_get_locked(mapping, cookie, change_attr);
+	folio = nfs_readdir_folio_get_locked(mapping, cookie, change_attr);
-	if (!page)
+	if (!folio)
 		return NULL;
-	if (desc->clear_cache && !nfs_readdir_page_needs_filling(page))
+	if (desc->clear_cache && !nfs_readdir_folio_needs_filling(folio))
-		nfs_readdir_page_reinit_array(page, cookie, change_attr);
+		nfs_readdir_folio_reinit_array(folio, cookie, change_attr);
-	return page;
+	return folio;
 }
 
 /*
@@ -1017,21 +1015,21 @@ static int find_and_lock_cache_page(struct nfs_readdir_descriptor *desc)
 	__be32 verf[NFS_DIR_VERIFIER_SIZE];
 	int res;
 
-	desc->page = nfs_readdir_page_get_cached(desc);
+	desc->folio = nfs_readdir_folio_get_cached(desc);
-	if (!desc->page)
+	if (!desc->folio)
 		return -ENOMEM;
-	if (nfs_readdir_page_needs_filling(desc->page)) {
+	if (nfs_readdir_folio_needs_filling(desc->folio)) {
 		/* Grow the dtsize if we had to go back for more pages */
-		if (desc->page_index == desc->page_index_max)
+		if (desc->folio_index == desc->folio_index_max)
 			nfs_grow_dtsize(desc);
-		desc->page_index_max = desc->page_index;
+		desc->folio_index_max = desc->folio_index;
 		trace_nfs_readdir_cache_fill(desc->file, nfsi->cookieverf,
 					     desc->last_cookie,
-					     desc->page->index, desc->dtsize);
+					     desc->folio->index, desc->dtsize);
 		res = nfs_readdir_xdr_to_array(desc, nfsi->cookieverf, verf,
-					       &desc->page, 1);
+					       &desc->folio, 1);
 		if (res < 0) {
-			nfs_readdir_page_unlock_and_put_cached(desc);
+			nfs_readdir_folio_unlock_and_put_cached(desc);
 			trace_nfs_readdir_cache_fill_done(inode, res);
 			if (res == -EBADCOOKIE || res == -ENOTSYNC) {
 				invalidate_inode_pages2(desc->file->f_mapping);
@@ -1059,7 +1057,7 @@ static int find_and_lock_cache_page(struct nfs_readdir_descriptor *desc)
 	res = nfs_readdir_search_array(desc);
 	if (res == 0)
 		return 0;
-	nfs_readdir_page_unlock_and_put_cached(desc);
+	nfs_readdir_folio_unlock_and_put_cached(desc);
 	return res;
 }
 
@@ -1087,7 +1085,7 @@ static void nfs_do_filldir(struct nfs_readdir_descriptor *desc,
 	unsigned int i;
 	bool first_emit = !desc->dir_cookie;
 
-	array = kmap_local_page(desc->page);
+	array = kmap_local_folio(desc->folio, 0);
 	for (i = desc->cache_entry_index; i < array->size; i++) {
 		struct nfs_cache_array_entry *ent;
 
@@ -1114,7 +1112,7 @@ static void nfs_do_filldir(struct nfs_readdir_descriptor *desc,
 			break;
 		}
 	}
-	if (array->page_is_eof)
+	if (array->folio_is_eof)
 		desc->eof = !desc->eob;
 
 	kunmap_local(array);
@@ -1136,7 +1134,7 @@ static void nfs_do_filldir(struct nfs_readdir_descriptor *desc,
  */
 static int uncached_readdir(struct nfs_readdir_descriptor *desc)
 {
-	struct page	**arrays;
+	struct folio	**arrays;
 	size_t		i, sz = 512;
 	__be32		verf[NFS_DIR_VERIFIER_SIZE];
 	int		status = -ENOMEM;
@@ -1147,14 +1145,14 @@ static int uncached_readdir(struct nfs_readdir_descriptor *desc)
 	arrays = kcalloc(sz, sizeof(*arrays), GFP_KERNEL);
 	if (!arrays)
 		goto out;
-	arrays[0] = nfs_readdir_page_array_alloc(desc->dir_cookie, GFP_KERNEL);
+	arrays[0] = nfs_readdir_folio_array_alloc(desc->dir_cookie, GFP_KERNEL);
 	if (!arrays[0])
 		goto out;
 
-	desc->page_index = 0;
+	desc->folio_index = 0;
 	desc->cache_entry_index = 0;
 	desc->last_cookie = desc->dir_cookie;
-	desc->page_index_max = 0;
+	desc->folio_index_max = 0;
 
 	trace_nfs_readdir_uncached(desc->file, desc->verf, desc->last_cookie,
 				   -1, desc->dtsize);
@@ -1166,10 +1164,10 @@ static int uncached_readdir(struct nfs_readdir_descriptor *desc)
 	}
 
 	for (i = 0; !desc->eob && i < sz && arrays[i]; i++) {
-		desc->page = arrays[i];
+		desc->folio = arrays[i];
 		nfs_do_filldir(desc, verf);
 	}
-	desc->page = NULL;
+	desc->folio = NULL;
 
 	/*
 	 * Grow the dtsize if we have to go back for more pages,
@@ -1179,16 +1177,16 @@ static int uncached_readdir(struct nfs_readdir_descriptor *desc)
 		if (!desc->eob)
 			nfs_grow_dtsize(desc);
 		else if (desc->buffer_fills == 1 &&
-			 i < (desc->page_index_max >> 1))
+			 i < (desc->folio_index_max >> 1))
 			nfs_shrink_dtsize(desc);
 	}
 out_free:
 	for (i = 0; i < sz && arrays[i]; i++)
-		nfs_readdir_page_array_free(arrays[i]);
+		nfs_readdir_folio_array_free(arrays[i]);
 out:
 	if (!nfs_readdir_use_cookie(desc->file))
 		nfs_readdir_rewind_search(desc);
-	desc->page_index_max = -1;
+	desc->folio_index_max = -1;
 	kfree(arrays);
 	dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __func__, status);
 	return status;
@@ -1240,11 +1238,11 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
 		goto out;
 	desc->file = file;
 	desc->ctx = ctx;
-	desc->page_index_max = -1;
+	desc->folio_index_max = -1;
 
 	spin_lock(&file->f_lock);
 	desc->dir_cookie = dir_ctx->dir_cookie;
-	desc->page_index = dir_ctx->page_index;
+	desc->folio_index = dir_ctx->page_index;
 	desc->last_cookie = dir_ctx->last_cookie;
 	desc->attr_gencount = dir_ctx->attr_gencount;
 	desc->eof = dir_ctx->eof;
@@ -1291,8 +1289,8 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
 			break;
 
 		nfs_do_filldir(desc, nfsi->cookieverf);
-		nfs_readdir_page_unlock_and_put_cached(desc);
+		nfs_readdir_folio_unlock_and_put_cached(desc);
-		if (desc->page_index == desc->page_index_max)
+		if (desc->folio_index == desc->folio_index_max)
 			desc->clear_cache = force_clear;
 	} while (!desc->eob && !desc->eof);
 
@@ -1300,7 +1298,7 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
 	dir_ctx->dir_cookie = desc->dir_cookie;
 	dir_ctx->last_cookie = desc->last_cookie;
 	dir_ctx->attr_gencount = desc->attr_gencount;
-	dir_ctx->page_index = desc->page_index;
+	dir_ctx->page_index = desc->folio_index;
 	dir_ctx->force_clear = force_clear;
 	dir_ctx->eof = desc->eof;
 	dir_ctx->dtsize = desc->dtsize;

fs/nfs/fscache.c

@@ -15,6 +15,9 @@
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/iversion.h>
+#include <linux/xarray.h>
+#include <linux/fscache.h>
+#include <linux/netfs.h>
 
 #include "internal.h"
 #include "iostat.h"
@@ -163,13 +166,14 @@ void nfs_fscache_init_inode(struct inode *inode)
 	struct nfs_server *nfss = NFS_SERVER(inode);
 	struct nfs_inode *nfsi = NFS_I(inode);
 
-	nfsi->fscache = NULL;
+	netfs_inode(inode)->cache = NULL;
 	if (!(nfss->fscache && S_ISREG(inode->i_mode)))
 		return;
 
 	nfs_fscache_update_auxdata(&auxdata, inode);
 
-	nfsi->fscache = fscache_acquire_cookie(NFS_SB(inode->i_sb)->fscache,
+	netfs_inode(inode)->cache = fscache_acquire_cookie(
+					       nfss->fscache,
 					       0,
 					       nfsi->fh.data, /* index_key */
 					       nfsi->fh.size,
@@ -183,11 +187,8 @@ void nfs_fscache_init_inode(struct inode *inode)
  */
 void nfs_fscache_clear_inode(struct inode *inode)
 {
-	struct nfs_inode *nfsi = NFS_I(inode);
+	fscache_relinquish_cookie(netfs_i_cookie(netfs_inode(inode)), false);
-	struct fscache_cookie *cookie = nfs_i_fscache(inode);
+	netfs_inode(inode)->cache = NULL;
-
-	fscache_relinquish_cookie(cookie, false);
-	nfsi->fscache = NULL;
 }
 
 /*
@@ -212,7 +213,7 @@ void nfs_fscache_clear_inode(struct inode *inode)
 void nfs_fscache_open_file(struct inode *inode, struct file *filp)
 {
 	struct nfs_fscache_inode_auxdata auxdata;
-	struct fscache_cookie *cookie = nfs_i_fscache(inode);
+	struct fscache_cookie *cookie = netfs_i_cookie(netfs_inode(inode));
 	bool open_for_write = inode_is_open_for_write(inode);
 
 	if (!fscache_cookie_valid(cookie))
@@ -230,115 +231,160 @@ EXPORT_SYMBOL_GPL(nfs_fscache_open_file);
 void nfs_fscache_release_file(struct inode *inode, struct file *filp)
 {
 	struct nfs_fscache_inode_auxdata auxdata;
-	struct fscache_cookie *cookie = nfs_i_fscache(inode);
+	struct fscache_cookie *cookie = netfs_i_cookie(netfs_inode(inode));
 	loff_t i_size = i_size_read(inode);
 
 	nfs_fscache_update_auxdata(&auxdata, inode);
 	fscache_unuse_cookie(cookie, &auxdata, &i_size);
 }
 
-/*
+int nfs_netfs_read_folio(struct file *file, struct folio *folio)
- * Fallback page reading interface.
- */
-static int fscache_fallback_read_page(struct inode *inode, struct page *page)
 {
-	struct netfs_cache_resources cres;
+	if (!netfs_inode(folio_inode(folio))->cache)
-	struct fscache_cookie *cookie = nfs_i_fscache(inode);
+		return -ENOBUFS;
-	struct iov_iter iter;
-	struct bio_vec bvec;
-	int ret;
 
-	memset(&cres, 0, sizeof(cres));
+	return netfs_read_folio(file, folio);
-	bvec_set_page(&bvec, page, PAGE_SIZE, 0);
-	iov_iter_bvec(&iter, ITER_DEST, &bvec, 1, PAGE_SIZE);
-
-	ret = fscache_begin_read_operation(&cres, cookie);
-	if (ret < 0)
-		return ret;
-
-	ret = fscache_read(&cres, page_offset(page), &iter, NETFS_READ_HOLE_FAIL,
-			   NULL, NULL);
-	fscache_end_operation(&cres);
-	return ret;
 }
 
-/*
+int nfs_netfs_readahead(struct readahead_control *ractl)
- * Fallback page writing interface.
- */
-static int fscache_fallback_write_page(struct inode *inode, struct page *page,
-				       bool no_space_allocated_yet)
 {
-	struct netfs_cache_resources cres;
+	struct inode *inode = ractl->mapping->host;
-	struct fscache_cookie *cookie = nfs_i_fscache(inode);
-	struct iov_iter iter;
-	struct bio_vec bvec;
-	loff_t start = page_offset(page);
-	size_t len = PAGE_SIZE;
-	int ret;
 
-	memset(&cres, 0, sizeof(cres));
+	if (!netfs_inode(inode)->cache)
-	bvec_set_page(&bvec, page, PAGE_SIZE, 0);
+		return -ENOBUFS;
-	iov_iter_bvec(&iter, ITER_SOURCE, &bvec, 1, PAGE_SIZE);
 
-	ret = fscache_begin_write_operation(&cres, cookie);
+	netfs_readahead(ractl);
-	if (ret < 0)
+	return 0;
-		return ret;
-
-	ret = cres.ops->prepare_write(&cres, &start, &len, i_size_read(inode),
-				      no_space_allocated_yet);
-	if (ret == 0)
-		ret = fscache_write(&cres, page_offset(page), &iter, NULL, NULL);
-	fscache_end_operation(&cres);
-	return ret;
 }
 
-/*
+static atomic_t nfs_netfs_debug_id;
- * Retrieve a page from fscache
+static int nfs_netfs_init_request(struct netfs_io_request *rreq, struct file *file)
- */
-int __nfs_fscache_read_page(struct inode *inode, struct page *page)
 {
-	int ret;
+	rreq->netfs_priv = get_nfs_open_context(nfs_file_open_context(file));
+	rreq->debug_id = atomic_inc_return(&nfs_netfs_debug_id);
 
-	trace_nfs_fscache_read_page(inode, page);
+	return 0;
-	if (PageChecked(page)) {
+}
-		ClearPageChecked(page);
+
-		ret = 1;
+static void nfs_netfs_free_request(struct netfs_io_request *rreq)
-		goto out;
+{
+	put_nfs_open_context(rreq->netfs_priv);
+}
+
+static inline int nfs_netfs_begin_cache_operation(struct netfs_io_request *rreq)
+{
+	return fscache_begin_read_operation(&rreq->cache_resources,
+					    netfs_i_cookie(netfs_inode(rreq->inode)));
+}
+
+static struct nfs_netfs_io_data *nfs_netfs_alloc(struct netfs_io_subrequest *sreq)
+{
+	struct nfs_netfs_io_data *netfs;
+
+	netfs = kzalloc(sizeof(*netfs), GFP_KERNEL_ACCOUNT);
+	if (!netfs)
+		return NULL;
+	netfs->sreq = sreq;
+	refcount_set(&netfs->refcount, 1);
+	return netfs;
+}
+
+static bool nfs_netfs_clamp_length(struct netfs_io_subrequest *sreq)
+{
+	size_t	rsize = NFS_SB(sreq->rreq->inode->i_sb)->rsize;
+
+	sreq->len = min(sreq->len, rsize);
+	return true;
+}
+
+static void nfs_netfs_issue_read(struct netfs_io_subrequest *sreq)
+{
+	struct nfs_netfs_io_data	*netfs;
+	struct nfs_pageio_descriptor	pgio;
+	struct inode *inode = sreq->rreq->inode;
+	struct nfs_open_context *ctx = sreq->rreq->netfs_priv;
+	struct page *page;
+	int err;
+	pgoff_t start = (sreq->start + sreq->transferred) >> PAGE_SHIFT;
+	pgoff_t last = ((sreq->start + sreq->len -
+			 sreq->transferred - 1) >> PAGE_SHIFT);
+	XA_STATE(xas, &sreq->rreq->mapping->i_pages, start);
+
+	nfs_pageio_init_read(&pgio, inode, false,
+			     &nfs_async_read_completion_ops);
+
+	netfs = nfs_netfs_alloc(sreq);
+	if (!netfs)
+		return netfs_subreq_terminated(sreq, -ENOMEM, false);
+
+	pgio.pg_netfs = netfs; /* used in completion */
+
+	xas_lock(&xas);
+	xas_for_each(&xas, page, last) {
+		/* nfs_read_add_folio() may schedule() due to pNFS layout and other RPCs  */
+		xas_pause(&xas);
+		xas_unlock(&xas);
+		err = nfs_read_add_folio(&pgio, ctx, page_folio(page));
+		if (err < 0) {
+			netfs->error = err;
+			goto out;
+		}
+		xas_lock(&xas);
 	}
-
+	xas_unlock(&xas);
-	ret = fscache_fallback_read_page(inode, page);
-	if (ret < 0) {
-		nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_FAIL);
-		SetPageChecked(page);
-		goto out;
-	}
-
-	/* Read completed synchronously */
-	nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_OK);
-	SetPageUptodate(page);
-	ret = 0;
 out:
-	trace_nfs_fscache_read_page_exit(inode, page, ret);
+	nfs_pageio_complete_read(&pgio);
-	return ret;
+	nfs_netfs_put(netfs);
 }
 
-/*
+void nfs_netfs_initiate_read(struct nfs_pgio_header *hdr)
- * Store a newly fetched page in fscache.  We can be certain there's no page
- * stored in the cache as yet otherwise we would've read it from there.
- */
-void __nfs_fscache_write_page(struct inode *inode, struct page *page)
 {
-	int ret;
+	struct nfs_netfs_io_data        *netfs = hdr->netfs;
 
-	trace_nfs_fscache_write_page(inode, page);
+	if (!netfs)
+		return;
 
-	ret = fscache_fallback_write_page(inode, page, true);
+	nfs_netfs_get(netfs);
-
-	if (ret != 0) {
-		nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL);
-		nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_UNCACHED);
-	} else {
-		nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_WRITTEN_OK);
-	}
-	trace_nfs_fscache_write_page_exit(inode, page, ret);
 }
+
+int nfs_netfs_folio_unlock(struct folio *folio)
+{
+	struct inode *inode = folio_file_mapping(folio)->host;
+
+	/*
+	 * If fscache is enabled, netfs will unlock pages.
+	 */
+	if (netfs_inode(inode)->cache)
+		return 0;
+
+	return 1;
+}
+
+void nfs_netfs_read_completion(struct nfs_pgio_header *hdr)
+{
+	struct nfs_netfs_io_data        *netfs = hdr->netfs;
+	struct netfs_io_subrequest      *sreq;
+
+	if (!netfs)
+		return;
+
+	sreq = netfs->sreq;
+	if (test_bit(NFS_IOHDR_EOF, &hdr->flags))
+		__set_bit(NETFS_SREQ_CLEAR_TAIL, &sreq->flags);
+
+	if (hdr->error)
+		netfs->error = hdr->error;
+	else
+		atomic64_add(hdr->res.count, &netfs->transferred);
+
+	nfs_netfs_put(netfs);
+	hdr->netfs = NULL;
+}
+
+const struct netfs_request_ops nfs_netfs_ops = {
+	.init_request		= nfs_netfs_init_request,
+	.free_request		= nfs_netfs_free_request,
+	.begin_cache_operation	= nfs_netfs_begin_cache_operation,
+	.issue_read		= nfs_netfs_issue_read,
+	.clamp_length		= nfs_netfs_clamp_length
+};

fs/nfs/fscache.h

@@ -34,6 +34,58 @@ struct nfs_fscache_inode_auxdata {
 	u64	change_attr;
 };
 
+struct nfs_netfs_io_data {
+	/*
+	 * NFS may split a netfs_io_subrequest into multiple RPCs, each
+	 * with their own read completion.  In netfs, we can only call
+	 * netfs_subreq_terminated() once for each subrequest.  Use the
+	 * refcount here to double as a marker of the last RPC completion,
+	 * and only call netfs via netfs_subreq_terminated() once.
+	 */
+	refcount_t			refcount;
+	struct netfs_io_subrequest	*sreq;
+
+	/*
+	 * Final disposition of the netfs_io_subrequest, sent in
+	 * netfs_subreq_terminated()
+	 */
+	atomic64_t	transferred;
+	int		error;
+};
+
+static inline void nfs_netfs_get(struct nfs_netfs_io_data *netfs)
+{
+	refcount_inc(&netfs->refcount);
+}
+
+static inline void nfs_netfs_put(struct nfs_netfs_io_data *netfs)
+{
+	ssize_t final_len;
+
+	/* Only the last RPC completion should call netfs_subreq_terminated() */
+	if (!refcount_dec_and_test(&netfs->refcount))
+		return;
+
+	/*
+	 * The NFS pageio interface may read a complete page, even when netfs
+	 * only asked for a partial page.  Specifically, this may be seen when
+	 * one thread is truncating a file while another one is reading the last
+	 * page of the file.
+	 * Correct the final length here to be no larger than the netfs subrequest
+	 * length, and thus avoid netfs's "Subreq overread" warning message.
+	 */
+	final_len = min_t(s64, netfs->sreq->len, atomic64_read(&netfs->transferred));
+	netfs_subreq_terminated(netfs->sreq, netfs->error ?: final_len, false);
+	kfree(netfs);
+}
+static inline void nfs_netfs_inode_init(struct nfs_inode *nfsi)
+{
+	netfs_inode_init(&nfsi->netfs, &nfs_netfs_ops);
+}
+extern void nfs_netfs_initiate_read(struct nfs_pgio_header *hdr);
+extern void nfs_netfs_read_completion(struct nfs_pgio_header *hdr);
+extern int nfs_netfs_folio_unlock(struct folio *folio);
+
 /*
  * fscache.c
  */
@@ -44,9 +96,8 @@ extern void nfs_fscache_init_inode(struct inode *);
 extern void nfs_fscache_clear_inode(struct inode *);
 extern void nfs_fscache_open_file(struct inode *, struct file *);
 extern void nfs_fscache_release_file(struct inode *, struct file *);
-
+extern int nfs_netfs_readahead(struct readahead_control *ractl);
-extern int __nfs_fscache_read_page(struct inode *, struct page *);
+extern int nfs_netfs_read_folio(struct file *file, struct folio *folio);
-extern void __nfs_fscache_write_page(struct inode *, struct page *);
 
 static inline bool nfs_fscache_release_folio(struct folio *folio, gfp_t gfp)
 {
@@ -54,34 +105,11 @@ static inline bool nfs_fscache_release_folio(struct folio *folio, gfp_t gfp)
 		if (current_is_kswapd() || !(gfp & __GFP_FS))
 			return false;
 		folio_wait_fscache(folio);
-		fscache_note_page_release(nfs_i_fscache(folio->mapping->host));
-		nfs_inc_fscache_stats(folio->mapping->host,
-				      NFSIOS_FSCACHE_PAGES_UNCACHED);
 	}
+	fscache_note_page_release(netfs_i_cookie(netfs_inode(folio->mapping->host)));
 	return true;
 }
 
-/*
- * Retrieve a page from an inode data storage object.
- */
-static inline int nfs_fscache_read_page(struct inode *inode, struct page *page)
-{
-	if (nfs_i_fscache(inode))
-		return __nfs_fscache_read_page(inode, page);
-	return -ENOBUFS;
-}
-
-/*
- * Store a page newly fetched from the server in an inode data storage object
- * in the cache.
- */
-static inline void nfs_fscache_write_page(struct inode *inode,
-					   struct page *page)
-{
-	if (nfs_i_fscache(inode))
-		__nfs_fscache_write_page(inode, page);
-}
-
 static inline void nfs_fscache_update_auxdata(struct nfs_fscache_inode_auxdata *auxdata,
 					      struct inode *inode)
 {
@@ -101,13 +129,10 @@ static inline void nfs_fscache_update_auxdata(struct nfs_fscache_inode_auxdata *
 static inline void nfs_fscache_invalidate(struct inode *inode, int flags)
 {
 	struct nfs_fscache_inode_auxdata auxdata;
-	struct nfs_inode *nfsi = NFS_I(inode);
+	struct fscache_cookie *cookie =  netfs_i_cookie(&NFS_I(inode)->netfs);
 
-	if (nfsi->fscache) {
+	nfs_fscache_update_auxdata(&auxdata, inode);
-		nfs_fscache_update_auxdata(&auxdata, inode);
+	fscache_invalidate(cookie, &auxdata, i_size_read(inode), flags);
-		fscache_invalidate(nfsi->fscache, &auxdata,
-				   i_size_read(inode), flags);
-	}
 }
 
 /*
@@ -120,7 +145,28 @@ static inline const char *nfs_server_fscache_state(struct nfs_server *server)
 	return "no ";
 }
 
+static inline void nfs_netfs_set_pgio_header(struct nfs_pgio_header *hdr,
+					     struct nfs_pageio_descriptor *desc)
+{
+	hdr->netfs = desc->pg_netfs;
+}
+static inline void nfs_netfs_set_pageio_descriptor(struct nfs_pageio_descriptor *desc,
+						   struct nfs_pgio_header *hdr)
+{
+	desc->pg_netfs = hdr->netfs;
+}
+static inline void nfs_netfs_reset_pageio_descriptor(struct nfs_pageio_descriptor *desc)
+{
+	desc->pg_netfs = NULL;
+}
 #else /* CONFIG_NFS_FSCACHE */
+static inline void nfs_netfs_inode_init(struct nfs_inode *nfsi) {}
+static inline void nfs_netfs_initiate_read(struct nfs_pgio_header *hdr) {}
+static inline void nfs_netfs_read_completion(struct nfs_pgio_header *hdr) {}
+static inline int nfs_netfs_folio_unlock(struct folio *folio)
+{
+	return 1;
+}
 static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}
 
 static inline void nfs_fscache_init_inode(struct inode *inode) {}
@@ -128,22 +174,29 @@ static inline void nfs_fscache_clear_inode(struct inode *inode) {}
 static inline void nfs_fscache_open_file(struct inode *inode,
 					 struct file *filp) {}
 static inline void nfs_fscache_release_file(struct inode *inode, struct file *file) {}
+static inline int nfs_netfs_readahead(struct readahead_control *ractl)
+{
+	return -ENOBUFS;
+}
+static inline int nfs_netfs_read_folio(struct file *file, struct folio *folio)
+{
+	return -ENOBUFS;
+}
 
 static inline bool nfs_fscache_release_folio(struct folio *folio, gfp_t gfp)
 {
 	return true; /* may release folio */
 }
-static inline int nfs_fscache_read_page(struct inode *inode, struct page *page)
-{
-	return -ENOBUFS;
-}
-static inline void nfs_fscache_write_page(struct inode *inode, struct page *page) {}
 static inline void nfs_fscache_invalidate(struct inode *inode, int flags) {}
 
 static inline const char *nfs_server_fscache_state(struct nfs_server *server)
 {
 	return "no ";
 }
-
+static inline void nfs_netfs_set_pgio_header(struct nfs_pgio_header *hdr,
+					     struct nfs_pageio_descriptor *desc) {}
+static inline void nfs_netfs_set_pageio_descriptor(struct nfs_pageio_descriptor *desc,
+						   struct nfs_pgio_header *hdr) {}
+static inline void nfs_netfs_reset_pageio_descriptor(struct nfs_pageio_descriptor *desc) {}
 #endif /* CONFIG_NFS_FSCACHE */
 #endif /* _NFS_FSCACHE_H */

fs/nfs/inode.c

@@ -208,11 +208,12 @@ void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
 
 	nfsi->cache_validity |= flags;
 
-	if (inode->i_mapping->nrpages == 0)
+	if (inode->i_mapping->nrpages == 0) {
-		nfsi->cache_validity &= ~(NFS_INO_INVALID_DATA |
+		nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
-					  NFS_INO_DATA_INVAL_DEFER);
+		nfs_ooo_clear(nfsi);
-	else if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
+	} else if (nfsi->cache_validity & NFS_INO_INVALID_DATA) {
-		nfsi->cache_validity &= ~NFS_INO_DATA_INVAL_DEFER;
+		nfs_ooo_clear(nfsi);
+	}
 	trace_nfs_set_cache_invalid(inode, 0);
 }
 EXPORT_SYMBOL_GPL(nfs_set_cache_invalid);
@@ -677,9 +678,10 @@ static int nfs_vmtruncate(struct inode * inode, loff_t offset)
 	trace_nfs_size_truncate(inode, offset);
 	i_size_write(inode, offset);
 	/* Optimisation */
-	if (offset == 0)
+	if (offset == 0) {
-		NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_DATA |
+		NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA;
-				NFS_INO_DATA_INVAL_DEFER);
+		nfs_ooo_clear(NFS_I(inode));
+	}
 	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE;
 
 	spin_unlock(&inode->i_lock);
@@ -1107,7 +1109,7 @@ void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
 
 	spin_lock(&inode->i_lock);
 	if (list_empty(&nfsi->open_files) &&
-	    (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER))
+	    nfs_ooo_test(nfsi))
 		nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA |
 						     NFS_INO_REVAL_FORCED);
 	list_add_tail_rcu(&ctx->list, &nfsi->open_files);
@@ -1351,8 +1353,8 @@ int nfs_clear_invalid_mapping(struct address_space *mapping)
 
 	set_bit(NFS_INO_INVALIDATING, bitlock);
 	smp_wmb();
-	nfsi->cache_validity &=
+	nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
-		~(NFS_INO_INVALID_DATA | NFS_INO_DATA_INVAL_DEFER);
+	nfs_ooo_clear(nfsi);
 	spin_unlock(&inode->i_lock);
 	trace_nfs_invalidate_mapping_enter(inode);
 	ret = nfs_invalidate_mapping(inode, mapping);
@@ -1814,6 +1816,66 @@ static int nfs_inode_finish_partial_attr_update(const struct nfs_fattr *fattr,
 	return 0;
 }
 
+static void nfs_ooo_merge(struct nfs_inode *nfsi,
+			  u64 start, u64 end)
+{
+	int i, cnt;
+
+	if (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER)
+		/* No point merging anything */
+		return;
+
+	if (!nfsi->ooo) {
+		nfsi->ooo = kmalloc(sizeof(*nfsi->ooo), GFP_ATOMIC);
+		if (!nfsi->ooo) {
+			nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
+			return;
+		}
+		nfsi->ooo->cnt = 0;
+	}
+
+	/* add this range, merging if possible */
+	cnt = nfsi->ooo->cnt;
+	for (i = 0; i < cnt; i++) {
+		if (end == nfsi->ooo->gap[i].start)
+			end = nfsi->ooo->gap[i].end;
+		else if (start == nfsi->ooo->gap[i].end)
+			start = nfsi->ooo->gap[i].start;
+		else
+			continue;
+		/* Remove 'i' from table and loop to insert the new range */
+		cnt -= 1;
+		nfsi->ooo->gap[i] = nfsi->ooo->gap[cnt];
+		i = -1;
+	}
+	if (start != end) {
+		if (cnt >= ARRAY_SIZE(nfsi->ooo->gap)) {
+			nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
+			kfree(nfsi->ooo);
+			nfsi->ooo = NULL;
+			return;
+		}
+		nfsi->ooo->gap[cnt].start = start;
+		nfsi->ooo->gap[cnt].end = end;
+		cnt += 1;
+	}
+	nfsi->ooo->cnt = cnt;
+}
+
+static void nfs_ooo_record(struct nfs_inode *nfsi,
+			   struct nfs_fattr *fattr)
+{
+	/* This reply was out-of-order, so record in the
+	 * pre/post change id, possibly cancelling
+	 * gaps created when iversion was jumpped forward.
+	 */
+	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) &&
+	    (fattr->valid & NFS_ATTR_FATTR_PRECHANGE))
+		nfs_ooo_merge(nfsi,
+			      fattr->change_attr,
+			      fattr->pre_change_attr);
+}
+
 static int nfs_refresh_inode_locked(struct inode *inode,
 				    struct nfs_fattr *fattr)
 {
@@ -1824,8 +1886,12 @@ static int nfs_refresh_inode_locked(struct inode *inode,
 
 	if (attr_cmp > 0 || nfs_inode_finish_partial_attr_update(fattr, inode))
 		ret = nfs_update_inode(inode, fattr);
-	else if (attr_cmp == 0)
+	else {
-		ret = nfs_check_inode_attributes(inode, fattr);
+		nfs_ooo_record(NFS_I(inode), fattr);
+
+		if (attr_cmp == 0)
+			ret = nfs_check_inode_attributes(inode, fattr);
+	}
 
 	trace_nfs_refresh_inode_exit(inode, ret);
 	return ret;
@@ -1916,6 +1982,8 @@ int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fa
 	if (attr_cmp < 0)
 		return 0;
 	if ((fattr->valid & NFS_ATTR_FATTR) == 0 || !attr_cmp) {
+		/* Record the pre/post change info before clearing PRECHANGE */
+		nfs_ooo_record(NFS_I(inode), fattr);
 		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
 				| NFS_ATTR_FATTR_PRESIZE
 				| NFS_ATTR_FATTR_PREMTIME
@@ -2070,6 +2138,15 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 
 	/* More cache consistency checks */
 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
+		if (!have_writers && nfsi->ooo && nfsi->ooo->cnt == 1 &&
+		    nfsi->ooo->gap[0].end == inode_peek_iversion_raw(inode)) {
+			/* There is one remaining gap that hasn't been
+			 * merged into iversion - do that now.
+			 */
+			inode_set_iversion_raw(inode, nfsi->ooo->gap[0].start);
+			kfree(nfsi->ooo);
+			nfsi->ooo = NULL;
+		}
 		if (!inode_eq_iversion_raw(inode, fattr->change_attr)) {
 			/* Could it be a race with writeback? */
 			if (!(have_writers || have_delegation)) {
@@ -2091,8 +2168,11 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 				dprintk("NFS: change_attr change on server for file %s/%ld\n",
 						inode->i_sb->s_id,
 						inode->i_ino);
-			} else if (!have_delegation)
+			} else if (!have_delegation) {
-				nfsi->cache_validity |= NFS_INO_DATA_INVAL_DEFER;
+				nfs_ooo_record(nfsi, fattr);
+				nfs_ooo_merge(nfsi, inode_peek_iversion_raw(inode),
+					      fattr->change_attr);
+			}
 			inode_set_iversion_raw(inode, fattr->change_attr);
 		}
 	} else {
@@ -2246,18 +2326,22 @@ struct inode *nfs_alloc_inode(struct super_block *sb)
 		return NULL;
 	nfsi->flags = 0UL;
 	nfsi->cache_validity = 0UL;
+	nfsi->ooo = NULL;
 #if IS_ENABLED(CONFIG_NFS_V4)
 	nfsi->nfs4_acl = NULL;
 #endif /* CONFIG_NFS_V4 */
 #ifdef CONFIG_NFS_V4_2
 	nfsi->xattr_cache = NULL;
 #endif
+	nfs_netfs_inode_init(nfsi);
+
 	return &nfsi->vfs_inode;
 }
 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
 
 void nfs_free_inode(struct inode *inode)
 {
+	kfree(NFS_I(inode)->ooo);
 	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
 }
 EXPORT_SYMBOL_GPL(nfs_free_inode);

fs/nfs/internal.h

@@ -452,6 +452,10 @@ extern void nfs_sb_deactive(struct super_block *sb);
 extern int nfs_client_for_each_server(struct nfs_client *clp,
 				      int (*fn)(struct nfs_server *, void *),
 				      void *data);
+#ifdef CONFIG_NFS_FSCACHE
+extern const struct netfs_request_ops nfs_netfs_ops;
+#endif
+
 /* io.c */
 extern void nfs_start_io_read(struct inode *inode);
 extern void nfs_end_io_read(struct inode *inode);
@@ -481,9 +485,14 @@ extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh, bool
 
 struct nfs_pgio_completion_ops;
 /* read.c */
+extern const struct nfs_pgio_completion_ops nfs_async_read_completion_ops;
 extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
 			struct inode *inode, bool force_mds,
 			const struct nfs_pgio_completion_ops *compl_ops);
+extern int nfs_read_add_folio(struct nfs_pageio_descriptor *pgio,
+			       struct nfs_open_context *ctx,
+			       struct folio *folio);
+extern void nfs_pageio_complete_read(struct nfs_pageio_descriptor *pgio);
 extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
 

fs/nfs/iostat.h

@@ -17,9 +17,6 @@
 
 struct nfs_iostats {
 	unsigned long long	bytes[__NFSIOS_BYTESMAX];
-#ifdef CONFIG_NFS_FSCACHE
-	unsigned long long	fscache[__NFSIOS_FSCACHEMAX];
-#endif
 	unsigned long		events[__NFSIOS_COUNTSMAX];
 } ____cacheline_aligned;
 
@@ -49,20 +46,6 @@ static inline void nfs_add_stats(const struct inode *inode,
 	nfs_add_server_stats(NFS_SERVER(inode), stat, addend);
 }
 
-#ifdef CONFIG_NFS_FSCACHE
-static inline void nfs_add_fscache_stats(struct inode *inode,
-					 enum nfs_stat_fscachecounters stat,
-					 long addend)
-{
-	this_cpu_add(NFS_SERVER(inode)->io_stats->fscache[stat], addend);
-}
-static inline void nfs_inc_fscache_stats(struct inode *inode,
-					 enum nfs_stat_fscachecounters stat)
-{
-	this_cpu_inc(NFS_SERVER(inode)->io_stats->fscache[stat]);
-}
-#endif
-
 static inline struct nfs_iostats __percpu *nfs_alloc_iostats(void)
 {
 	return alloc_percpu(struct nfs_iostats);

fs/nfs/nfs42xdr.c

@@ -1122,7 +1122,6 @@ static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
 	uint32_t segments;
 	struct read_plus_segment *segs;
 	int status, i;
-	char scratch_buf[16];
 	__be32 *p;
 
 	status = decode_op_hdr(xdr, OP_READ_PLUS);
@@ -1143,7 +1142,6 @@ static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
 	if (!segs)
 		return -ENOMEM;
 
-	xdr_set_scratch_buffer(xdr, &scratch_buf, sizeof(scratch_buf));
 	status = -EIO;
 	for (i = 0; i < segments; i++) {
 		status = decode_read_plus_segment(xdr, &segs[i]);
@@ -1348,6 +1346,8 @@ static int nfs4_xdr_dec_read_plus(struct rpc_rqst *rqstp,
 	struct compound_hdr hdr;
 	int status;
 
+	xdr_set_scratch_buffer(xdr, res->scratch, sizeof(res->scratch));
+
 	status = decode_compound_hdr(xdr, &hdr);
 	if (status)
 		goto out;

fs/nfs/nfs4proc.c

@@ -5439,6 +5439,8 @@ static bool nfs4_read_plus_not_supported(struct rpc_task *task,
 
 static int nfs4_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
 {
+	if (hdr->res.scratch)
+		kfree(hdr->res.scratch);
 	if (!nfs4_sequence_done(task, &hdr->res.seq_res))
 		return -EAGAIN;
 	if (nfs4_read_stateid_changed(task, &hdr->args))
@@ -5452,17 +5454,22 @@ static int nfs4_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
 }
 
 #if defined CONFIG_NFS_V4_2 && defined CONFIG_NFS_V4_2_READ_PLUS
-static void nfs42_read_plus_support(struct nfs_pgio_header *hdr,
+static bool nfs42_read_plus_support(struct nfs_pgio_header *hdr,
 				    struct rpc_message *msg)
 {
 	/* Note: We don't use READ_PLUS with pNFS yet */
-	if (nfs_server_capable(hdr->inode, NFS_CAP_READ_PLUS) && !hdr->ds_clp)
+	if (nfs_server_capable(hdr->inode, NFS_CAP_READ_PLUS) && !hdr->ds_clp) {
 		msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ_PLUS];
+		hdr->res.scratch = kmalloc(32, GFP_KERNEL);
+		return hdr->res.scratch != NULL;
+	}
+	return false;
 }
 #else
-static void nfs42_read_plus_support(struct nfs_pgio_header *hdr,
+static bool nfs42_read_plus_support(struct nfs_pgio_header *hdr,
 				    struct rpc_message *msg)
 {
+	return false;
 }
 #endif /* CONFIG_NFS_V4_2 */
 
@@ -5472,8 +5479,8 @@ static void nfs4_proc_read_setup(struct nfs_pgio_header *hdr,
 	hdr->timestamp   = jiffies;
 	if (!hdr->pgio_done_cb)
 		hdr->pgio_done_cb = nfs4_read_done_cb;
-	msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ];
+	if (!nfs42_read_plus_support(hdr, msg))
-	nfs42_read_plus_support(hdr, msg);
+		msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ];
 	nfs4_init_sequence(&hdr->args.seq_args, &hdr->res.seq_res, 0, 0);
 }
 

fs/nfs/nfs4state.c

@@ -67,6 +67,8 @@
 
 #define OPENOWNER_POOL_SIZE	8
 
+static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp);
+
 const nfs4_stateid zero_stateid = {
 	{ .data = { 0 } },
 	.type = NFS4_SPECIAL_STATEID_TYPE,
@@ -330,6 +332,8 @@ do_confirm:
 	status = nfs4_proc_create_session(clp, cred);
 	if (status != 0)
 		goto out;
+	if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R))
+		nfs4_state_start_reclaim_reboot(clp);
 	nfs41_finish_session_reset(clp);
 	nfs_mark_client_ready(clp, NFS_CS_READY);
 out:
@@ -1205,10 +1209,6 @@ void nfs4_schedule_state_manager(struct nfs_client *clp)
 {
 	struct task_struct *task;
 	char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
-	struct rpc_clnt *cl = clp->cl_rpcclient;
-
-	while (cl != cl->cl_parent)
-		cl = cl->cl_parent;
 
 	set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
 	if (test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state) != 0) {

fs/nfs/nfstrace.h

@@ -39,7 +39,6 @@
 			{ BIT(NFS_INO_STALE), "STALE" }, \
 			{ BIT(NFS_INO_ACL_LRU_SET), "ACL_LRU_SET" }, \
 			{ BIT(NFS_INO_INVALIDATING), "INVALIDATING" }, \
-			{ BIT(NFS_INO_FSCACHE), "FSCACHE" }, \
 			{ BIT(NFS_INO_LAYOUTCOMMIT), "NEED_LAYOUTCOMMIT" }, \
 			{ BIT(NFS_INO_LAYOUTCOMMITTING), "LAYOUTCOMMIT" }, \
 			{ BIT(NFS_INO_LAYOUTSTATS), "LAYOUTSTATS" }, \
@@ -1243,96 +1242,6 @@ TRACE_EVENT(nfs_readpage_short,
 		)
 );
 
-DECLARE_EVENT_CLASS(nfs_fscache_page_event,
-		TP_PROTO(
-			const struct inode *inode,
-			struct page *page
-		),
-
-		TP_ARGS(inode, page),
-
-		TP_STRUCT__entry(
-			__field(dev_t, dev)
-			__field(u32, fhandle)
-			__field(u64, fileid)
-			__field(loff_t, offset)
-		),
-
-		TP_fast_assign(
-			const struct nfs_inode *nfsi = NFS_I(inode);
-			const struct nfs_fh *fh = &nfsi->fh;
-
-			__entry->offset = page_index(page) << PAGE_SHIFT;
-			__entry->dev = inode->i_sb->s_dev;
-			__entry->fileid = nfsi->fileid;
-			__entry->fhandle = nfs_fhandle_hash(fh);
-		),
-
-		TP_printk(
-			"fileid=%02x:%02x:%llu fhandle=0x%08x "
-			"offset=%lld",
-			MAJOR(__entry->dev), MINOR(__entry->dev),
-			(unsigned long long)__entry->fileid,
-			__entry->fhandle,
-			(long long)__entry->offset
-		)
-);
-DECLARE_EVENT_CLASS(nfs_fscache_page_event_done,
-		TP_PROTO(
-			const struct inode *inode,
-			struct page *page,
-			int error
-		),
-
-		TP_ARGS(inode, page, error),
-
-		TP_STRUCT__entry(
-			__field(int, error)
-			__field(dev_t, dev)
-			__field(u32, fhandle)
-			__field(u64, fileid)
-			__field(loff_t, offset)
-		),
-
-		TP_fast_assign(
-			const struct nfs_inode *nfsi = NFS_I(inode);
-			const struct nfs_fh *fh = &nfsi->fh;
-
-			__entry->offset = page_index(page) << PAGE_SHIFT;
-			__entry->dev = inode->i_sb->s_dev;
-			__entry->fileid = nfsi->fileid;
-			__entry->fhandle = nfs_fhandle_hash(fh);
-			__entry->error = error;
-		),
-
-		TP_printk(
-			"fileid=%02x:%02x:%llu fhandle=0x%08x "
-			"offset=%lld error=%d",
-			MAJOR(__entry->dev), MINOR(__entry->dev),
-			(unsigned long long)__entry->fileid,
-			__entry->fhandle,
-			(long long)__entry->offset, __entry->error
-		)
-);
-#define DEFINE_NFS_FSCACHE_PAGE_EVENT(name) \
-	DEFINE_EVENT(nfs_fscache_page_event, name, \
-			TP_PROTO( \
-				const struct inode *inode, \
-				struct page *page \
-			), \
-			TP_ARGS(inode, page))
-#define DEFINE_NFS_FSCACHE_PAGE_EVENT_DONE(name) \
-	DEFINE_EVENT(nfs_fscache_page_event_done, name, \
-			TP_PROTO( \
-				const struct inode *inode, \
-				struct page *page, \
-				int error \
-			), \
-			TP_ARGS(inode, page, error))
-DEFINE_NFS_FSCACHE_PAGE_EVENT(nfs_fscache_read_page);
-DEFINE_NFS_FSCACHE_PAGE_EVENT_DONE(nfs_fscache_read_page_exit);
-DEFINE_NFS_FSCACHE_PAGE_EVENT(nfs_fscache_write_page);
-DEFINE_NFS_FSCACHE_PAGE_EVENT_DONE(nfs_fscache_write_page_exit);
 
 TRACE_EVENT(nfs_pgio_error,
 	TP_PROTO(

fs/nfs/pagelist.c

@@ -26,6 +26,7 @@
 #include "internal.h"
 #include "pnfs.h"
 #include "nfstrace.h"
+#include "fscache.h"
 
 #define NFSDBG_FACILITY		NFSDBG_PAGECACHE
 
@@ -105,6 +106,7 @@ void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
 	hdr->good_bytes = mirror->pg_count;
 	hdr->io_completion = desc->pg_io_completion;
 	hdr->dreq = desc->pg_dreq;
+	nfs_netfs_set_pgio_header(hdr, desc);
 	hdr->release = release;
 	hdr->completion_ops = desc->pg_completion_ops;
 	if (hdr->completion_ops->init_hdr)
@@ -941,6 +943,7 @@ void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
 	desc->pg_lseg = NULL;
 	desc->pg_io_completion = NULL;
 	desc->pg_dreq = NULL;
+	nfs_netfs_reset_pageio_descriptor(desc);
 	desc->pg_bsize = bsize;
 
 	desc->pg_mirror_count = 1;
@@ -1477,6 +1480,7 @@ int nfs_pageio_resend(struct nfs_pageio_descriptor *desc,
 
 	desc->pg_io_completion = hdr->io_completion;
 	desc->pg_dreq = hdr->dreq;
+	nfs_netfs_set_pageio_descriptor(desc, hdr);
 	list_splice_init(&hdr->pages, &pages);
 	while (!list_empty(&pages)) {
 		struct nfs_page *req = nfs_list_entry(pages.next);

fs/nfs/read.c

@@ -31,7 +31,7 @@
 
 #define NFSDBG_FACILITY		NFSDBG_PAGECACHE
 
-static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops;
+const struct nfs_pgio_completion_ops nfs_async_read_completion_ops;
 static const struct nfs_rw_ops nfs_rw_read_ops;
 
 static struct kmem_cache *nfs_rdata_cachep;
@@ -74,7 +74,7 @@ void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
 }
 EXPORT_SYMBOL_GPL(nfs_pageio_init_read);
 
-static void nfs_pageio_complete_read(struct nfs_pageio_descriptor *pgio)
+void nfs_pageio_complete_read(struct nfs_pageio_descriptor *pgio)
 {
 	struct nfs_pgio_mirror *pgm;
 	unsigned long npages;
@@ -110,28 +110,17 @@ EXPORT_SYMBOL_GPL(nfs_pageio_reset_read_mds);
 
 static void nfs_readpage_release(struct nfs_page *req, int error)
 {
-	struct inode *inode = d_inode(nfs_req_openctx(req)->dentry);
 	struct folio *folio = nfs_page_to_folio(req);
 
-	dprintk("NFS: read done (%s/%llu %d@%lld)\n", inode->i_sb->s_id,
-		(unsigned long long)NFS_FILEID(inode), req->wb_bytes,
-		(long long)req_offset(req));
-
 	if (nfs_error_is_fatal_on_server(error) && error != -ETIMEDOUT)
 		folio_set_error(folio);
-	if (nfs_page_group_sync_on_bit(req, PG_UNLOCKPAGE)) {
+	if (nfs_page_group_sync_on_bit(req, PG_UNLOCKPAGE))
-		if (folio_test_uptodate(folio))
+		if (nfs_netfs_folio_unlock(folio))
-			nfs_fscache_write_page(inode, &folio->page);
+			folio_unlock(folio);
-		folio_unlock(folio);
+
-	}
 	nfs_release_request(req);
 }
 
-struct nfs_readdesc {
-	struct nfs_pageio_descriptor pgio;
-	struct nfs_open_context *ctx;
-};
-
 static void nfs_page_group_set_uptodate(struct nfs_page *req)
 {
 	if (nfs_page_group_sync_on_bit(req, PG_UPTODATE))
@@ -153,7 +142,8 @@ static void nfs_read_completion(struct nfs_pgio_header *hdr)
 
 		if (test_bit(NFS_IOHDR_EOF, &hdr->flags)) {
 			/* note: regions of the page not covered by a
-			 * request are zeroed in readpage_async_filler */
+			 * request are zeroed in nfs_read_add_folio
+			 */
 			if (bytes > hdr->good_bytes) {
 				/* nothing in this request was good, so zero
 				 * the full extent of the request */
@@ -181,6 +171,8 @@ static void nfs_read_completion(struct nfs_pgio_header *hdr)
 		nfs_list_remove_request(req);
 		nfs_readpage_release(req, error);
 	}
+	nfs_netfs_read_completion(hdr);
+
 out:
 	hdr->release(hdr);
 }
@@ -191,6 +183,7 @@ static void nfs_initiate_read(struct nfs_pgio_header *hdr,
 			      struct rpc_task_setup *task_setup_data, int how)
 {
 	rpc_ops->read_setup(hdr, msg);
+	nfs_netfs_initiate_read(hdr);
 	trace_nfs_initiate_read(hdr);
 }
 
@@ -206,7 +199,7 @@ nfs_async_read_error(struct list_head *head, int error)
 	}
 }
 
-static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops = {
+const struct nfs_pgio_completion_ops nfs_async_read_completion_ops = {
 	.error_cleanup = nfs_async_read_error,
 	.completion = nfs_read_completion,
 };
@@ -281,7 +274,9 @@ static void nfs_readpage_result(struct rpc_task *task,
 		nfs_readpage_retry(task, hdr);
 }
 
-static int readpage_async_filler(struct nfs_readdesc *desc, struct folio *folio)
+int nfs_read_add_folio(struct nfs_pageio_descriptor *pgio,
+		       struct nfs_open_context *ctx,
+		       struct folio *folio)
 {
 	struct inode *inode = folio_file_mapping(folio)->host;
 	struct nfs_server *server = NFS_SERVER(inode);
@@ -297,29 +292,21 @@ static int readpage_async_filler(struct nfs_readdesc *desc, struct folio *folio)
 
 	aligned_len = min_t(unsigned int, ALIGN(len, rsize), fsize);
 
-	if (!IS_SYNC(inode)) {
+	new = nfs_page_create_from_folio(ctx, folio, 0, aligned_len);
-		error = nfs_fscache_read_page(inode, &folio->page);
+	if (IS_ERR(new)) {
-		if (error == 0)
+		error = PTR_ERR(new);
-			goto out_unlock;
+		goto out;
 	}
 
-	new = nfs_page_create_from_folio(desc->ctx, folio, 0, aligned_len);
-	if (IS_ERR(new))
-		goto out_error;
-
 	if (len < fsize)
 		folio_zero_segment(folio, len, fsize);
-	if (!nfs_pageio_add_request(&desc->pgio, new)) {
+	if (!nfs_pageio_add_request(pgio, new)) {
 		nfs_list_remove_request(new);
-		error = desc->pgio.pg_error;
+		error = pgio->pg_error;
 		nfs_readpage_release(new, error);
 		goto out;
 	}
 	return 0;
-out_error:
-	error = PTR_ERR(new);
-out_unlock:
-	folio_unlock(folio);
 out:
 	return error;
 }
@@ -332,8 +319,9 @@ out:
  */
 int nfs_read_folio(struct file *file, struct folio *folio)
 {
-	struct nfs_readdesc desc;
 	struct inode *inode = file_inode(file);
+	struct nfs_pageio_descriptor pgio;
+	struct nfs_open_context *ctx;
 	int ret;
 
 	trace_nfs_aop_readpage(inode, folio);
@@ -357,38 +345,43 @@ int nfs_read_folio(struct file *file, struct folio *folio)
 	if (NFS_STALE(inode))
 		goto out_unlock;
 
-	desc.ctx = get_nfs_open_context(nfs_file_open_context(file));
+	ret = nfs_netfs_read_folio(file, folio);
-
+	if (!ret)
-	xchg(&desc.ctx->error, 0);
-	nfs_pageio_init_read(&desc.pgio, inode, false,
-			     &nfs_async_read_completion_ops);
-
-	ret = readpage_async_filler(&desc, folio);
-	if (ret)
 		goto out;
 
-	nfs_pageio_complete_read(&desc.pgio);
+	ctx = get_nfs_open_context(nfs_file_open_context(file));
-	ret = desc.pgio.pg_error < 0 ? desc.pgio.pg_error : 0;
+
+	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);
+	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(&desc.ctx->error, 0);
+			ret = xchg(&ctx->error, 0);
 	}
+out_put:
+	put_nfs_open_context(ctx);
 out:
-	put_nfs_open_context(desc.ctx);
 	trace_nfs_aop_readpage_done(inode, folio, ret);
 	return ret;
 out_unlock:
 	folio_unlock(folio);
-	trace_nfs_aop_readpage_done(inode, folio, ret);
+	goto out;
-	return ret;
 }
 
 void nfs_readahead(struct readahead_control *ractl)
 {
+	struct nfs_pageio_descriptor pgio;
+	struct nfs_open_context *ctx;
 	unsigned int nr_pages = readahead_count(ractl);
 	struct file *file = ractl->file;
-	struct nfs_readdesc desc;
 	struct inode *inode = ractl->mapping->host;
 	struct folio *folio;
 	int ret;
@@ -401,26 +394,30 @@ void nfs_readahead(struct readahead_control *ractl)
 	if (NFS_STALE(inode))
 		goto out;
 
+	ret = nfs_netfs_readahead(ractl);
+	if (!ret)
+		goto out;
+
 	if (file == NULL) {
 		ret = -EBADF;
-		desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
+		ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
-		if (desc.ctx == NULL)
+		if (ctx == NULL)
 			goto out;
 	} else
-		desc.ctx = get_nfs_open_context(nfs_file_open_context(file));
+		ctx = get_nfs_open_context(nfs_file_open_context(file));
 
-	nfs_pageio_init_read(&desc.pgio, inode, false,
+	nfs_pageio_init_read(&pgio, inode, false,
 			     &nfs_async_read_completion_ops);
 
 	while ((folio = readahead_folio(ractl)) != NULL) {
-		ret = readpage_async_filler(&desc, folio);
+		ret = nfs_read_add_folio(&pgio, ctx, folio);
 		if (ret)
 			break;
 	}
 
-	nfs_pageio_complete_read(&desc.pgio);
+	nfs_pageio_complete_read(&pgio);
 
-	put_nfs_open_context(desc.ctx);
+	put_nfs_open_context(ctx);
 out:
 	trace_nfs_aop_readahead_done(inode, nr_pages, ret);
 }

fs/nfs/super.c

@@ -692,10 +692,6 @@ int nfs_show_stats(struct seq_file *m, struct dentry *root)
 			totals.events[i] += stats->events[i];
 		for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 			totals.bytes[i] += stats->bytes[i];
-#ifdef CONFIG_NFS_FSCACHE
-		for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
-			totals.fscache[i] += stats->fscache[i];
-#endif
 
 		preempt_enable();
 	}
@@ -706,13 +702,6 @@ int nfs_show_stats(struct seq_file *m, struct dentry *root)
 	seq_puts(m, "\n\tbytes:\t");
 	for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 		seq_printf(m, "%Lu ", totals.bytes[i]);
-#ifdef CONFIG_NFS_FSCACHE
-	if (nfss->options & NFS_OPTION_FSCACHE) {
-		seq_puts(m, "\n\tfsc:\t");
-		for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
-			seq_printf(m, "%Lu ", totals.fscache[i]);
-	}
-#endif
 	seq_putc(m, '\n');
 
 	rpc_clnt_show_stats(m, nfss->client);

include/linux/nfs_fs.h

@@ -31,6 +31,10 @@
 #include <linux/sunrpc/auth.h>
 #include <linux/sunrpc/clnt.h>
 
+#ifdef CONFIG_NFS_FSCACHE
+#include <linux/netfs.h>
+#endif
+
 #include <linux/nfs.h>
 #include <linux/nfs2.h>
 #include <linux/nfs3.h>
@@ -191,6 +195,39 @@ struct nfs_inode {
 	/* Open contexts for shared mmap writes */
 	struct list_head	open_files;
 
+	/* Keep track of out-of-order replies.
+	 * The ooo array contains start/end pairs of
+	 * numbers from the changeid sequence when
+	 * the inode's iversion has been updated.
+	 * It also contains end/start pair (i.e. reverse order)
+	 * of sections of the changeid sequence that have
+	 * been seen in replies from the server.
+	 * Normally these should match and when both
+	 * A:B and B:A are found in ooo, they are both removed.
+	 * And if a reply with A:B causes an iversion update
+	 * of A:B, then neither are added.
+	 * When a reply has pre_change that doesn't match
+	 * iversion, then the changeid pair and any consequent
+	 * change in iversion ARE added.  Later replies
+	 * might fill in the gaps, or possibly a gap is caused
+	 * by a change from another client.
+	 * When a file or directory is opened, if the ooo table
+	 * is not empty, then we assume the gaps were due to
+	 * another client and we invalidate the cached data.
+	 *
+	 * We can only track a limited number of concurrent gaps.
+	 * Currently that limit is 16.
+	 * We allocate the table on demand.  If there is insufficient
+	 * memory, then we probably cannot cache the file anyway
+	 * so there is no loss.
+	 */
+	struct {
+		int cnt;
+		struct {
+			u64 start, end;
+		} gap[16];
+	} *ooo;
+
 #if IS_ENABLED(CONFIG_NFS_V4)
 	struct nfs4_cached_acl	*nfs4_acl;
         /* NFSv4 state */
@@ -204,14 +241,15 @@ struct nfs_inode {
 	/* how many bytes have been written/read and how many bytes queued up */
 	__u64 write_io;
 	__u64 read_io;
-#ifdef CONFIG_NFS_FSCACHE
-	struct fscache_cookie	*fscache;
-#endif
-	struct inode		vfs_inode;
-
 #ifdef CONFIG_NFS_V4_2
 	struct nfs4_xattr_cache *xattr_cache;
 #endif
+	union {
+		struct inode		vfs_inode;
+#ifdef CONFIG_NFS_FSCACHE
+		struct netfs_inode	netfs; /* netfs context and VFS inode */
+#endif
+	};
 };
 
 struct nfs4_copy_state {
@@ -276,7 +314,6 @@ struct nfs4_copy_state {
 #define NFS_INO_ACL_LRU_SET	(2)		/* Inode is on the LRU list */
 #define NFS_INO_INVALIDATING	(3)		/* inode is being invalidated */
 #define NFS_INO_PRESERVE_UNLINKED (4)		/* preserve file if removed while open */
-#define NFS_INO_FSCACHE		(5)		/* inode can be cached by FS-Cache */
 #define NFS_INO_LAYOUTCOMMIT	(9)		/* layoutcommit required */
 #define NFS_INO_LAYOUTCOMMITTING (10)		/* layoutcommit inflight */
 #define NFS_INO_LAYOUTSTATS	(11)		/* layoutstats inflight */
@@ -329,15 +366,6 @@ static inline int NFS_STALE(const struct inode *inode)
 	return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
 }
 
-static inline struct fscache_cookie *nfs_i_fscache(struct inode *inode)
-{
-#ifdef CONFIG_NFS_FSCACHE
-	return NFS_I(inode)->fscache;
-#else
-	return NULL;
-#endif
-}
-
 static inline __u64 NFS_FILEID(const struct inode *inode)
 {
 	return NFS_I(inode)->fileid;
@@ -617,6 +645,20 @@ nfs_fileid_to_ino_t(u64 fileid)
 	return ino;
 }
 
+static inline void nfs_ooo_clear(struct nfs_inode *nfsi)
+{
+	nfsi->cache_validity &= ~NFS_INO_DATA_INVAL_DEFER;
+	kfree(nfsi->ooo);
+	nfsi->ooo = NULL;
+}
+
+static inline bool nfs_ooo_test(struct nfs_inode *nfsi)
+{
+	return (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER) ||
+		(nfsi->ooo && nfsi->ooo->cnt > 0);
+
+}
+
 #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
 
 /* We need to block new opens while a file is being unlinked.

include/linux/nfs_iostat.h

@@ -119,16 +119,4 @@ enum nfs_stat_eventcounters {
 	__NFSIOS_COUNTSMAX,
 };
 
-/*
- * NFS local caching servicing counters
- */
-enum nfs_stat_fscachecounters {
-	NFSIOS_FSCACHE_PAGES_READ_OK,
-	NFSIOS_FSCACHE_PAGES_READ_FAIL,
-	NFSIOS_FSCACHE_PAGES_WRITTEN_OK,
-	NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL,
-	NFSIOS_FSCACHE_PAGES_UNCACHED,
-	__NFSIOS_FSCACHEMAX,
-};
-
 #endif	/* _LINUX_NFS_IOSTAT */

include/linux/nfs_page.h

@@ -105,6 +105,9 @@ struct nfs_pageio_descriptor {
 	struct pnfs_layout_segment *pg_lseg;
 	struct nfs_io_completion *pg_io_completion;
 	struct nfs_direct_req	*pg_dreq;
+#ifdef CONFIG_NFS_FSCACHE
+	void			*pg_netfs;
+#endif
 	unsigned int		pg_bsize;	/* default bsize for mirrors */
 
 	u32			pg_mirror_count;

include/linux/nfs_xdr.h

@@ -670,6 +670,7 @@ struct nfs_pgio_res {
 		struct {
 			unsigned int		replen;		/* used by read */
 			int			eof;		/* used by read */
+			void *			scratch;	/* used by read */
 		};
 		struct {
 			struct nfs_writeverf *	verf;		/* used by write */
@@ -1619,6 +1620,9 @@ struct nfs_pgio_header {
 	const struct nfs_rw_ops	*rw_ops;
 	struct nfs_io_completion *io_completion;
 	struct nfs_direct_req	*dreq;
+#ifdef CONFIG_NFS_FSCACHE
+	void			*netfs;
+#endif
 
 	int			pnfs_error;
 	int			error;		/* merge with pnfs_error */

include/linux/sunrpc/sched.h

@@ -90,8 +90,7 @@ struct rpc_task {
 #endif
 	unsigned char		tk_priority : 2,/* Task priority */
 				tk_garb_retry : 2,
-				tk_cred_retry : 2,
+				tk_cred_retry : 2;
-				tk_rebind_retry : 2;
 };
 
 typedef void			(*rpc_action)(struct rpc_task *);

net/sunrpc/clnt.c

@@ -2050,9 +2050,6 @@ call_bind_status(struct rpc_task *task)
 			status = -EOPNOTSUPP;
 			break;
 		}
-		if (task->tk_rebind_retry == 0)
-			break;
-		task->tk_rebind_retry--;
 		rpc_delay(task, 3*HZ);
 		goto retry_timeout;
 	case -ENOBUFS:

net/sunrpc/sched.c

@@ -817,7 +817,6 @@ rpc_init_task_statistics(struct rpc_task *task)
 	/* Initialize retry counters */
 	task->tk_garb_retry = 2;
 	task->tk_cred_retry = 2;
-	task->tk_rebind_retry = 2;
 
 	/* starting timestamp */
 	task->tk_start = ktime_get();

net/sunrpc/sysctl.c

@@ -40,25 +40,6 @@ EXPORT_SYMBOL_GPL(nlm_debug);
 
 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 
-static struct ctl_table_header *sunrpc_table_header;
-static struct ctl_table sunrpc_table[];
-
-void
-rpc_register_sysctl(void)
-{
-	if (!sunrpc_table_header)
-		sunrpc_table_header = register_sysctl_table(sunrpc_table);
-}
-
-void
-rpc_unregister_sysctl(void)
-{
-	if (sunrpc_table_header) {
-		unregister_sysctl_table(sunrpc_table_header);
-		sunrpc_table_header = NULL;
-	}
-}
-
 static int proc_do_xprt(struct ctl_table *table, int write,
 			void *buffer, size_t *lenp, loff_t *ppos)
 {
@@ -142,6 +123,7 @@ done:
 	return 0;
 }
 
+static struct ctl_table_header *sunrpc_table_header;
 
 static struct ctl_table debug_table[] = {
 	{
@@ -181,13 +163,19 @@ static struct ctl_table debug_table[] = {
 	{ }
 };
 
-static struct ctl_table sunrpc_table[] = {
+void
-	{
+rpc_register_sysctl(void)
-		.procname	= "sunrpc",
+{
-		.mode		= 0555,
+	if (!sunrpc_table_header)
-		.child		= debug_table
+		sunrpc_table_header = register_sysctl("sunrpc", debug_table);
-	},
+}
-	{ }
-};
 
+void
+rpc_unregister_sysctl(void)
+{
+	if (sunrpc_table_header) {
+		unregister_sysctl_table(sunrpc_table_header);
+		sunrpc_table_header = NULL;
+	}
+}
 #endif

net/sunrpc/xprtrdma/transport.c

@@ -140,15 +140,6 @@ static struct ctl_table xr_tunables_table[] = {
 	{ },
 };
 
-static struct ctl_table sunrpc_table[] = {
-	{
-		.procname	= "sunrpc",
-		.mode		= 0555,
-		.child		= xr_tunables_table
-	},
-	{ },
-};
-
 #endif
 
 static const struct rpc_xprt_ops xprt_rdma_procs;
@@ -799,7 +790,7 @@ int xprt_rdma_init(void)
 
 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 	if (!sunrpc_table_header)
-		sunrpc_table_header = register_sysctl_table(sunrpc_table);
+		sunrpc_table_header = register_sysctl("sunrpc", xr_tunables_table);
 #endif
 	return 0;
 }

net/sunrpc/xprtsock.c

@@ -78,7 +78,7 @@ static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
 
 /*
  * We can register our own files under /proc/sys/sunrpc by
- * calling register_sysctl_table() again.  The files in that
+ * calling register_sysctl() again.  The files in that
  * directory become the union of all files registered there.
  *
  * We simply need to make sure that we don't collide with
@@ -158,15 +158,6 @@ static struct ctl_table xs_tunables_table[] = {
 	{ },
 };
 
-static struct ctl_table sunrpc_table[] = {
-	{
-		.procname	= "sunrpc",
-		.mode		= 0555,
-		.child		= xs_tunables_table
-	},
-	{ },
-};
-
 /*
  * Wait duration for a reply from the RPC portmapper.
  */
@@ -3178,7 +3169,7 @@ static struct xprt_class	xs_bc_tcp_transport = {
 int init_socket_xprt(void)
 {
 	if (!sunrpc_table_header)
-		sunrpc_table_header = register_sysctl_table(sunrpc_table);
+		sunrpc_table_header = register_sysctl("sunrpc", xs_tunables_table);
 
 	xprt_register_transport(&xs_local_transport);
 	xprt_register_transport(&xs_udp_transport);