Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 202 insertions, 0 deletions

diff --git a/fs/nfs/fscache.h b/fs/nfs/fscache.h
new file mode 100644
index 0000000000..2dc6445449
--- /dev/null
+++ b/fs/nfs/fscache.h
@@ -0,0 +1,202 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* NFS filesystem cache interface definitions
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#ifndef _NFS_FSCACHE_H
+#define _NFS_FSCACHE_H
+
+#include <linux/swap.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_mount.h>
+#include <linux/nfs4_mount.h>
+#include <linux/fscache.h>
+#include <linux/iversion.h>
+
+#ifdef CONFIG_NFS_FSCACHE
+
+/*
+ * Definition of the auxiliary data attached to NFS inode storage objects
+ * within the cache.
+ *
+ * The contents of this struct are recorded in the on-disk local cache in the
+ * auxiliary data attached to the data storage object backing an inode.  This
+ * permits coherency to be managed when a new inode binds to an already extant
+ * cache object.
+ */
+struct nfs_fscache_inode_auxdata {
+	s64	mtime_sec;
+	s64	mtime_nsec;
+	s64	ctime_sec;
+	s64	ctime_nsec;
+	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
+ */
+extern int nfs_fscache_get_super_cookie(struct super_block *, const char *, int);
+extern void nfs_fscache_release_super_cookie(struct super_block *);
+
+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_netfs_read_folio(struct file *file, struct folio *folio);
+
+static inline bool nfs_fscache_release_folio(struct folio *folio, gfp_t gfp)
+{
+	if (folio_test_fscache(folio)) {
+		if (current_is_kswapd() || !(gfp & __GFP_FS))
+			return false;
+		folio_wait_fscache(folio);
+	}
+	fscache_note_page_release(netfs_i_cookie(netfs_inode(folio->mapping->host)));
+	return true;
+}
+
+static inline void nfs_fscache_update_auxdata(struct nfs_fscache_inode_auxdata *auxdata,
+					      struct inode *inode)
+{
+	memset(auxdata, 0, sizeof(*auxdata));
+	auxdata->mtime_sec  = inode->i_mtime.tv_sec;
+	auxdata->mtime_nsec = inode->i_mtime.tv_nsec;
+	auxdata->ctime_sec  = inode_get_ctime(inode).tv_sec;
+	auxdata->ctime_nsec = inode_get_ctime(inode).tv_nsec;
+
+	if (NFS_SERVER(inode)->nfs_client->rpc_ops->version == 4)
+		auxdata->change_attr = inode_peek_iversion_raw(inode);
+}
+
+/*
+ * Invalidate the contents of fscache for this inode.  This will not sleep.
+ */
+static inline void nfs_fscache_invalidate(struct inode *inode, int flags)
+{
+	struct nfs_fscache_inode_auxdata auxdata;
+	struct fscache_cookie *cookie =  netfs_i_cookie(&NFS_I(inode)->netfs);
+
+	nfs_fscache_update_auxdata(&auxdata, inode);
+	fscache_invalidate(cookie, &auxdata, i_size_read(inode), flags);
+}
+
+/*
+ * indicate the client caching state as readable text
+ */
+static inline const char *nfs_server_fscache_state(struct nfs_server *server)
+{
+	if (server->fscache)
+		return "yes";
+	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) {}
+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 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 */