v4.19.13 snapshot.
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h
new file mode 100644
index 0000000..de50a34
--- /dev/null
+++ b/fs/nfs/flexfilelayout/flexfilelayout.h
@@ -0,0 +1,237 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * NFSv4 flexfile layout driver data structures.
+ *
+ * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
+ *
+ * Tao Peng <bergwolf@primarydata.com>
+ */
+
+#ifndef FS_NFS_NFS4FLEXFILELAYOUT_H
+#define FS_NFS_NFS4FLEXFILELAYOUT_H
+
+#define FF_FLAGS_NO_LAYOUTCOMMIT 1
+#define FF_FLAGS_NO_IO_THRU_MDS 2
+#define FF_FLAGS_NO_READ_IO 4
+
+#include <linux/refcount.h>
+#include "../pnfs.h"
+
+/* XXX: Let's filter out insanely large mirror count for now to avoid oom
+ * due to network error etc. */
+#define NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT 4096
+
+/* LAYOUTSTATS report interval in ms */
+#define FF_LAYOUTSTATS_REPORT_INTERVAL (60000L)
+#define FF_LAYOUTSTATS_MAXDEV 4
+
+struct nfs4_ff_ds_version {
+ u32 version;
+ u32 minor_version;
+ u32 rsize;
+ u32 wsize;
+ bool tightly_coupled;
+};
+
+/* chained in global deviceid hlist */
+struct nfs4_ff_layout_ds {
+ struct nfs4_deviceid_node id_node;
+ u32 ds_versions_cnt;
+ struct nfs4_ff_ds_version *ds_versions;
+ struct nfs4_pnfs_ds *ds;
+};
+
+struct nfs4_ff_layout_ds_err {
+ struct list_head list; /* linked in mirror error_list */
+ u64 offset;
+ u64 length;
+ int status;
+ enum nfs_opnum4 opnum;
+ nfs4_stateid stateid;
+ struct nfs4_deviceid deviceid;
+};
+
+struct nfs4_ff_io_stat {
+ __u64 ops_requested;
+ __u64 bytes_requested;
+ __u64 ops_completed;
+ __u64 bytes_completed;
+ __u64 bytes_not_delivered;
+ ktime_t total_busy_time;
+ ktime_t aggregate_completion_time;
+};
+
+struct nfs4_ff_busy_timer {
+ ktime_t start_time;
+ atomic_t n_ops;
+};
+
+struct nfs4_ff_layoutstat {
+ struct nfs4_ff_io_stat io_stat;
+ struct nfs4_ff_busy_timer busy_timer;
+};
+
+struct nfs4_ff_layout_mirror {
+ struct pnfs_layout_hdr *layout;
+ struct list_head mirrors;
+ u32 ds_count;
+ u32 efficiency;
+ struct nfs4_deviceid devid;
+ struct nfs4_ff_layout_ds *mirror_ds;
+ u32 fh_versions_cnt;
+ struct nfs_fh *fh_versions;
+ nfs4_stateid stateid;
+ struct rpc_cred __rcu *ro_cred;
+ struct rpc_cred __rcu *rw_cred;
+ refcount_t ref;
+ spinlock_t lock;
+ unsigned long flags;
+ struct nfs4_ff_layoutstat read_stat;
+ struct nfs4_ff_layoutstat write_stat;
+ ktime_t start_time;
+ u32 report_interval;
+};
+
+#define NFS4_FF_MIRROR_STAT_AVAIL (0)
+
+struct nfs4_ff_layout_segment {
+ struct pnfs_layout_segment generic_hdr;
+ u64 stripe_unit;
+ u32 flags;
+ u32 mirror_array_cnt;
+ struct nfs4_ff_layout_mirror **mirror_array;
+};
+
+struct nfs4_flexfile_layout {
+ struct pnfs_layout_hdr generic_hdr;
+ struct pnfs_ds_commit_info commit_info;
+ struct list_head mirrors;
+ struct list_head error_list; /* nfs4_ff_layout_ds_err */
+ ktime_t last_report_time; /* Layoutstat report times */
+};
+
+struct nfs4_flexfile_layoutreturn_args {
+ struct list_head errors;
+ struct nfs42_layoutstat_devinfo devinfo[FF_LAYOUTSTATS_MAXDEV];
+ unsigned int num_errors;
+ unsigned int num_dev;
+ struct page *pages[1];
+};
+
+static inline struct nfs4_flexfile_layout *
+FF_LAYOUT_FROM_HDR(struct pnfs_layout_hdr *lo)
+{
+ return container_of(lo, struct nfs4_flexfile_layout, generic_hdr);
+}
+
+static inline struct nfs4_ff_layout_segment *
+FF_LAYOUT_LSEG(struct pnfs_layout_segment *lseg)
+{
+ return container_of(lseg,
+ struct nfs4_ff_layout_segment,
+ generic_hdr);
+}
+
+static inline struct nfs4_deviceid_node *
+FF_LAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg, u32 idx)
+{
+ if (idx >= FF_LAYOUT_LSEG(lseg)->mirror_array_cnt ||
+ FF_LAYOUT_LSEG(lseg)->mirror_array[idx] == NULL ||
+ FF_LAYOUT_LSEG(lseg)->mirror_array[idx]->mirror_ds == NULL)
+ return NULL;
+ return &FF_LAYOUT_LSEG(lseg)->mirror_array[idx]->mirror_ds->id_node;
+}
+
+static inline struct nfs4_ff_layout_ds *
+FF_LAYOUT_MIRROR_DS(struct nfs4_deviceid_node *node)
+{
+ return container_of(node, struct nfs4_ff_layout_ds, id_node);
+}
+
+static inline struct nfs4_ff_layout_mirror *
+FF_LAYOUT_COMP(struct pnfs_layout_segment *lseg, u32 idx)
+{
+ if (idx >= FF_LAYOUT_LSEG(lseg)->mirror_array_cnt)
+ return NULL;
+ return FF_LAYOUT_LSEG(lseg)->mirror_array[idx];
+}
+
+static inline u32
+FF_LAYOUT_MIRROR_COUNT(struct pnfs_layout_segment *lseg)
+{
+ return FF_LAYOUT_LSEG(lseg)->mirror_array_cnt;
+}
+
+static inline bool
+ff_layout_no_fallback_to_mds(struct pnfs_layout_segment *lseg)
+{
+ return FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_IO_THRU_MDS;
+}
+
+static inline bool
+ff_layout_no_read_on_rw(struct pnfs_layout_segment *lseg)
+{
+ return FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_READ_IO;
+}
+
+static inline bool
+ff_layout_test_devid_unavailable(struct nfs4_deviceid_node *node)
+{
+ /*
+ * Flexfiles should never mark a DS unavailable, but if it does
+ * print a (ratelimited) warning as this can affect performance.
+ */
+ if (nfs4_test_deviceid_unavailable(node)) {
+ u32 *p = (u32 *)node->deviceid.data;
+
+ pr_warn_ratelimited("NFS: flexfiles layout referencing an "
+ "unavailable device [%x%x%x%x]\n",
+ p[0], p[1], p[2], p[3]);
+ return true;
+ }
+ return false;
+}
+
+static inline int
+nfs4_ff_layout_ds_version(struct pnfs_layout_segment *lseg, u32 ds_idx)
+{
+ return FF_LAYOUT_COMP(lseg, ds_idx)->mirror_ds->ds_versions[0].version;
+}
+
+struct nfs4_ff_layout_ds *
+nfs4_ff_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
+ gfp_t gfp_flags);
+void nfs4_ff_layout_put_deviceid(struct nfs4_ff_layout_ds *mirror_ds);
+void nfs4_ff_layout_free_deviceid(struct nfs4_ff_layout_ds *mirror_ds);
+int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
+ struct nfs4_ff_layout_mirror *mirror, u64 offset,
+ u64 length, int status, enum nfs_opnum4 opnum,
+ gfp_t gfp_flags);
+int ff_layout_encode_ds_ioerr(struct xdr_stream *xdr, const struct list_head *head);
+void ff_layout_free_ds_ioerr(struct list_head *head);
+unsigned int ff_layout_fetch_ds_ioerr(struct pnfs_layout_hdr *lo,
+ const struct pnfs_layout_range *range,
+ struct list_head *head,
+ unsigned int maxnum);
+struct nfs_fh *
+nfs4_ff_layout_select_ds_fh(struct pnfs_layout_segment *lseg, u32 mirror_idx);
+int
+nfs4_ff_layout_select_ds_stateid(struct pnfs_layout_segment *lseg,
+ u32 mirror_idx,
+ nfs4_stateid *stateid);
+
+struct nfs4_pnfs_ds *
+nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
+ bool fail_return);
+
+struct rpc_clnt *
+nfs4_ff_find_or_create_ds_client(struct pnfs_layout_segment *lseg,
+ u32 ds_idx,
+ struct nfs_client *ds_clp,
+ struct inode *inode);
+struct rpc_cred *ff_layout_get_ds_cred(struct pnfs_layout_segment *lseg,
+ u32 ds_idx, struct rpc_cred *mdscred);
+bool ff_layout_avoid_mds_available_ds(struct pnfs_layout_segment *lseg);
+bool ff_layout_avoid_read_on_rw(struct pnfs_layout_segment *lseg);
+
+#endif /* FS_NFS_NFS4FLEXFILELAYOUT_H */