Merge tag 'nfs-for-6.14-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client updates from Anna Schumaker:
 "New Features:
   - Enable using direct IO with localio
   - Added localio related tracepoints

  Bugfixes:
   - Sunrpc fixes for working with a very large cl_tasks list
   - Fix a possible buffer overflow in nfs_sysfs_link_rpc_client()
   - Fixes for handling reconnections with localio
   - Fix how the NFS_FSCACHE kconfig option interacts with NETFS_SUPPORT
   - Fix COPY_NOTIFY xdr_buf size calculations
   - pNFS/Flexfiles fix for retrying requesting a layout segment for
     reads
   - Sunrpc fix for retrying on EKEYEXPIRED error when the TGT is
     expired

  Cleanups:
   - Various other nfs & nfsd localio cleanups
   - Prepratory patches for async copy improvements that are under
     development
   - Make OFFLOAD_CANCEL, LAYOUTSTATS, and LAYOUTERR moveable to other
     xprts
   - Add netns inum and srcaddr to debugfs rpc_xprt info"

* tag 'nfs-for-6.14-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (28 commits)
  SUNRPC: do not retry on EKEYEXPIRED when user TGT ticket expired
  sunrpc: add netns inum and srcaddr to debugfs rpc_xprt info
  pnfs/flexfiles: retry getting layout segment for reads
  NFSv4.2: make LAYOUTSTATS and LAYOUTERROR MOVEABLE
  NFSv4.2: mark OFFLOAD_CANCEL MOVEABLE
  NFSv4.2: fix COPY_NOTIFY xdr buf size calculation
  NFS: Rename struct nfs4_offloadcancel_data
  NFS: Fix typo in OFFLOAD_CANCEL comment
  NFS: CB_OFFLOAD can return NFS4ERR_DELAY
  nfs: Make NFS_FSCACHE select NETFS_SUPPORT instead of depending on it
  nfs: fix incorrect error handling in LOCALIO
  nfs: probe for LOCALIO when v3 client reconnects to server
  nfs: probe for LOCALIO when v4 client reconnects to server
  nfs/localio: remove redundant code and simplify LOCALIO enablement
  nfs_common: add nfs_localio trace events
  nfs_common: track all open nfsd_files per LOCALIO nfs_client
  nfs_common: rename nfslocalio nfs_uuid_lock to nfs_uuids_lock
  nfsd: nfsd_file_acquire_local no longer returns GC'd nfsd_file
  nfsd: rename nfsd_serv_ prefixed methods and variables with nfsd_net_
  nfsd: update percpu_ref to manage references on nfsd_net
  ...

6 files changed, 59 insertions, 19 deletions

diff --git a/include/linux/nfs_common.h b/include/linux/nfs_common.h
index 5fc02df88252..a541c3a02887 100644
--- a/include/linux/nfs_common.h
+++ b/include/linux/nfs_common.h
@@ -9,9 +9,10 @@
 #include <uapi/linux/nfs.h>
 
 /* Mapping from NFS error code to "errno" error code. */
-#define errno_NFSERR_IO EIO
 
 int nfs_stat_to_errno(enum nfs_stat status);
 int nfs4_stat_to_errno(int stat);
 
+__u32 nfs_localio_errno_to_nfs4_stat(int errno);
+
 #endif /* _LINUX_NFS_COMMON_H */
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 039898d70954..67ae2c3f41d2 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -77,6 +77,23 @@ struct nfs_lock_context {
 	struct rcu_head	rcu_head;
 };
 
+struct nfs_file_localio {
+	struct nfsd_file __rcu *ro_file;
+	struct nfsd_file __rcu *rw_file;
+	struct list_head list;
+	void __rcu *nfs_uuid; /* opaque pointer to 'nfs_uuid_t' */
+};
+
+static inline void nfs_localio_file_init(struct nfs_file_localio *nfl)
+{
+#if IS_ENABLED(CONFIG_NFS_LOCALIO)
+	nfl->ro_file = NULL;
+	nfl->rw_file = NULL;
+	INIT_LIST_HEAD(&nfl->list);
+	nfl->nfs_uuid = NULL;
+#endif
+}
+
 struct nfs4_state;
 struct nfs_open_context {
 	struct nfs_lock_context lock_context;
@@ -87,15 +104,16 @@ struct nfs_open_context {
 	struct nfs4_state *state;
 	fmode_t mode;
 
+	int error;
 	unsigned long flags;
 #define NFS_CONTEXT_BAD			(2)
 #define NFS_CONTEXT_UNLOCK	(3)
 #define NFS_CONTEXT_FILE_OPEN		(4)
-	int error;
 
-	struct list_head list;
 	struct nfs4_threshold	*mdsthreshold;
+	struct list_head list;
 	struct rcu_head	rcu_head;
+	struct nfs_file_localio nfl;
 };
 
 struct nfs_open_dir_context {
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index b804346a9741..f00bfcee7120 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -50,7 +50,6 @@ struct nfs_client {
 #define NFS_CS_DS		7		/* - Server is a DS */
 #define NFS_CS_REUSEPORT	8		/* - reuse src port on reconnect */
 #define NFS_CS_PNFS		9		/* - Server used for pnfs */
-#define NFS_CS_LOCAL_IO		10		/* - client is local */
 	struct sockaddr_storage	cl_addr;	/* server identifier */
 	size_t			cl_addrlen;
 	char *			cl_hostname;	/* hostname of server */
@@ -132,7 +131,7 @@ struct nfs_client {
 	struct timespec64	cl_nfssvc_boot;
 	seqlock_t		cl_boot_lock;
 	nfs_uuid_t		cl_uuid;
-	spinlock_t		cl_localio_lock;
+	struct work_struct	cl_local_probe_work;
 #endif /* CONFIG_NFS_LOCALIO */
 };
 
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index e74a87bb18a4..162b7c0c3555 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1632,6 +1632,7 @@ enum {
 	NFS_IOHDR_RESEND_PNFS,
 	NFS_IOHDR_RESEND_MDS,
 	NFS_IOHDR_UNSTABLE_WRITES,
+	NFS_IOHDR_ODIRECT,
 };
 
 struct nfs_io_completion;
diff --git a/include/linux/nfslocalio.h b/include/linux/nfslocalio.h
index 9202f4b24343..9aa8a43843d7 100644
--- a/include/linux/nfslocalio.h
+++ b/include/linux/nfslocalio.h
@@ -6,9 +6,6 @@
 #ifndef __LINUX_NFSLOCALIO_H
 #define __LINUX_NFSLOCALIO_H
 
-/* nfsd_file structure is purposely kept opaque to NFS client */
-struct nfsd_file;
-
 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
 
 #include <linux/module.h>
@@ -19,6 +16,9 @@ struct nfsd_file;
 #include <linux/nfs.h>
 #include <net/net_namespace.h>
 
+struct nfs_client;
+struct nfs_file_localio;
+
 /*
  * Useful to allow a client to negotiate if localio
  * possible with its server.
@@ -27,28 +27,38 @@ struct nfsd_file;
  */
 typedef struct {
 	uuid_t uuid;
+	unsigned nfs3_localio_probe_count;
+	/* this struct is over a cacheline, avoid bouncing */
+	spinlock_t ____cacheline_aligned lock;
 	struct list_head list;
+	spinlock_t *list_lock; /* nn->local_clients_lock */
 	struct net __rcu *net; /* nfsd's network namespace */
 	struct auth_domain *dom; /* auth_domain for localio */
+	/* Local files to close when net is shut down or exports change */
+	struct list_head files;
 } nfs_uuid_t;
 
 void nfs_uuid_init(nfs_uuid_t *);
 bool nfs_uuid_begin(nfs_uuid_t *);
 void nfs_uuid_end(nfs_uuid_t *);
-void nfs_uuid_is_local(const uuid_t *, struct list_head *,
+void nfs_uuid_is_local(const uuid_t *, struct list_head *, spinlock_t *,
 		       struct net *, struct auth_domain *, struct module *);
-void nfs_uuid_invalidate_clients(struct list_head *list);
-void nfs_uuid_invalidate_one_client(nfs_uuid_t *nfs_uuid);
+
+void nfs_localio_enable_client(struct nfs_client *clp);
+void nfs_localio_disable_client(struct nfs_client *clp);
+void nfs_localio_invalidate_clients(struct list_head *nn_local_clients,
+				    spinlock_t *nn_local_clients_lock);
 
 /* localio needs to map filehandle -> struct nfsd_file */
 extern struct nfsd_file *
 nfsd_open_local_fh(struct net *, struct auth_domain *, struct rpc_clnt *,
 		   const struct cred *, const struct nfs_fh *,
 		   const fmode_t) __must_hold(rcu);
+void nfs_close_local_fh(struct nfs_file_localio *);
 
 struct nfsd_localio_operations {
-	bool (*nfsd_serv_try_get)(struct net *);
-	void (*nfsd_serv_put)(struct net *);
+	bool (*nfsd_net_try_get)(struct net *);
+	void (*nfsd_net_put)(struct net *);
 	struct nfsd_file *(*nfsd_open_local_fh)(struct net *,
 						struct auth_domain *,
 						struct rpc_clnt *,
@@ -56,6 +66,8 @@ struct nfsd_localio_operations {
 						const struct nfs_fh *,
 						const fmode_t);
 	struct net *(*nfsd_file_put_local)(struct nfsd_file *);
+	struct nfsd_file *(*nfsd_file_get)(struct nfsd_file *);
+	void (*nfsd_file_put)(struct nfsd_file *);
 	struct file *(*nfsd_file_file)(struct nfsd_file *);
 } ____cacheline_aligned;
 
@@ -64,17 +76,18 @@ extern const struct nfsd_localio_operations *nfs_to;
 
 struct nfsd_file *nfs_open_local_fh(nfs_uuid_t *,
 		   struct rpc_clnt *, const struct cred *,
-		   const struct nfs_fh *, const fmode_t);
+		   const struct nfs_fh *, struct nfs_file_localio *,
+		   const fmode_t);
 
 static inline void nfs_to_nfsd_net_put(struct net *net)
 {
 	/*
-	 * Once reference to nfsd_serv is dropped, NFSD could be
-	 * unloaded, so ensure safe return from nfsd_file_put_local()
-	 * by always taking RCU.
+	 * Once reference to net (and associated nfsd_serv) is dropped, NFSD
+	 * could be unloaded, so ensure safe return from nfsd_net_put() by
+	 * always taking RCU.
 	 */
 	rcu_read_lock();
-	nfs_to->nfsd_serv_put(net);
+	nfs_to->nfsd_net_put(net);
 	rcu_read_unlock();
 }
 
@@ -91,12 +104,19 @@ static inline void nfs_to_nfsd_file_put_local(struct nfsd_file *localio)
 }
 
 #else   /* CONFIG_NFS_LOCALIO */
+
+struct nfs_file_localio;
+static inline void nfs_close_local_fh(struct nfs_file_localio *nfl)
+{
+}
 static inline void nfsd_localio_ops_init(void)
 {
 }
-static inline void nfs_to_nfsd_file_put_local(struct nfsd_file *localio)
+struct nfs_client;
+static inline void nfs_localio_disable_client(struct nfs_client *clp)
 {
 }
+
 #endif  /* CONFIG_NFS_LOCALIO */
 
 #endif  /* __LINUX_NFSLOCALIO_H */
diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 5321585c778f..fec976e58174 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -93,6 +93,7 @@ struct rpc_clnt {
 	const struct cred	*cl_cred;
 	unsigned int		cl_max_connect; /* max number of transports not to the same IP */
 	struct super_block *pipefs_sb;
+	atomic_t		cl_task_count;
 };
 
 /*