1 files changed, 424 insertions, 0 deletions

diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
new file mode 100644
index 000000000000..96bf4e6f45be
--- /dev/null
+++ b/fs/nfs/pnfs.h
@@ -0,0 +1,424 @@
+/*
+ *  pNFS client data structures.
+ *
+ *  Copyright (c) 2002
+ *  The Regents of the University of Michigan
+ *  All Rights Reserved
+ *
+ *  Dean Hildebrand <dhildebz@umich.edu>
+ *
+ *  Permission is granted to use, copy, create derivative works, and
+ *  redistribute this software and such derivative works for any purpose,
+ *  so long as the name of the University of Michigan is not used in
+ *  any advertising or publicity pertaining to the use or distribution
+ *  of this software without specific, written prior authorization. If
+ *  the above copyright notice or any other identification of the
+ *  University of Michigan is included in any copy of any portion of
+ *  this software, then the disclaimer below must also be included.
+ *
+ *  This software is provided as is, without representation or warranty
+ *  of any kind either express or implied, including without limitation
+ *  the implied warranties of merchantability, fitness for a particular
+ *  purpose, or noninfringement.  The Regents of the University of
+ *  Michigan shall not be liable for any damages, including special,
+ *  indirect, incidental, or consequential damages, with respect to any
+ *  claim arising out of or in connection with the use of the software,
+ *  even if it has been or is hereafter advised of the possibility of
+ *  such damages.
+ */
+
+#ifndef FS_NFS_PNFS_H
+#define FS_NFS_PNFS_H
+
+#include <linux/nfs_fs.h>
+#include <linux/nfs_page.h>
+
+enum {
+        NFS_LSEG_VALID = 0,     /* cleared when lseg is recalled/returned */
+        NFS_LSEG_ROC,           /* roc bit received from server */
+};
+
+struct pnfs_layout_segment {
+        struct list_head pls_list;
+        struct pnfs_layout_range pls_range;
+        atomic_t pls_refcount;
+        unsigned long pls_flags;
+        struct pnfs_layout_hdr *pls_layout;
+        struct rpc_cred *pls_lc_cred; /* LAYOUTCOMMIT credential */
+        loff_t pls_end_pos; /* LAYOUTCOMMIT write end */
+};
+
+enum pnfs_try_status {
+        PNFS_ATTEMPTED     = 0,
+        PNFS_NOT_ATTEMPTED = 1,
+};
+
+#ifdef CONFIG_NFS_V4_1
+
+#define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"
+
+enum {
+        NFS_LAYOUT_RO_FAILED = 0,       /* get ro layout failed stop trying */
+        NFS_LAYOUT_RW_FAILED,           /* get rw layout failed stop trying */
+        NFS_LAYOUT_BULK_RECALL,         /* bulk recall affecting layout */
+        NFS_LAYOUT_ROC,                 /* some lseg had roc bit set */
+        NFS_LAYOUT_DESTROYED,           /* no new use of layout allowed */
+};
+
+enum layoutdriver_policy_flags {
+        /* Should the pNFS client commit and return the layout upon a setattr */
+        PNFS_LAYOUTRET_ON_SETATTR       = 1 << 0,
+};
+
+struct nfs4_deviceid_node;
+
+/* Per-layout driver specific registration structure */
+struct pnfs_layoutdriver_type {
+        struct list_head pnfs_tblid;
+        const u32 id;
+        const char *name;
+        struct module *owner;
+        unsigned flags;
+
+        struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
+        void (*free_layout_hdr) (struct pnfs_layout_hdr *);
+
+        struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
+        void (*free_lseg) (struct pnfs_layout_segment *lseg);
+
+        /* test for nfs page cache coalescing */
+        bool (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *);
+
+        /* Returns true if layoutdriver wants to divert this request to
+         * driver's commit routine.
+         */
+        bool (*mark_pnfs_commit)(struct pnfs_layout_segment *lseg);
+        struct list_head * (*choose_commit_list) (struct nfs_page *req);
+        int (*commit_pagelist)(struct inode *inode, struct list_head *mds_pages, int how);
+
+        /*
+         * Return PNFS_ATTEMPTED to indicate the layout code has attempted
+         * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
+         */
+        enum pnfs_try_status (*read_pagelist) (struct nfs_read_data *nfs_data);
+        enum pnfs_try_status (*write_pagelist) (struct nfs_write_data *nfs_data, int how);
+
+        void (*free_deviceid_node) (struct nfs4_deviceid_node *);
+
+        void (*encode_layoutreturn) (struct pnfs_layout_hdr *layoutid,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs4_layoutreturn_args *args);
+
+        void (*encode_layoutcommit) (struct pnfs_layout_hdr *layoutid,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs4_layoutcommit_args *args);
+};
+
+struct pnfs_layout_hdr {
+        atomic_t                plh_refcount;
+        struct list_head        plh_layouts;   /* other client layouts */
+        struct list_head        plh_bulk_recall; /* clnt list of bulk recalls */
+        struct list_head        plh_segs;      /* layout segments list */
+        nfs4_stateid            plh_stateid;
+        atomic_t                plh_outstanding; /* number of RPCs out */
+        unsigned long           plh_block_lgets; /* block LAYOUTGET if >0 */
+        u32                     plh_barrier; /* ignore lower seqids */
+        unsigned long           plh_flags;
+        struct inode            *plh_inode;
+};
+
+struct pnfs_device {
+        struct nfs4_deviceid dev_id;
+        unsigned int  layout_type;
+        unsigned int  mincount;
+        struct page **pages;
+        unsigned int  pgbase;
+        unsigned int  pglen;
+};
+
+extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
+extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
+
+/* nfs4proc.c */
+extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
+                                   struct pnfs_device *dev);
+extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
+extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp);
+
+/* pnfs.c */
+void get_layout_hdr(struct pnfs_layout_hdr *lo);
+void put_lseg(struct pnfs_layout_segment *lseg);
+struct pnfs_layout_segment *
+pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
+                   loff_t pos, u64 count, enum pnfs_iomode access_type,
+                   gfp_t gfp_flags);
+void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
+void unset_pnfs_layoutdriver(struct nfs_server *);
+enum pnfs_try_status pnfs_try_to_write_data(struct nfs_write_data *,
+                                             const struct rpc_call_ops *, int);
+enum pnfs_try_status pnfs_try_to_read_data(struct nfs_read_data *,
+                                            const struct rpc_call_ops *);
+bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req);
+int pnfs_layout_process(struct nfs4_layoutget *lgp);
+void pnfs_free_lseg_list(struct list_head *tmp_list);
+void pnfs_destroy_layout(struct nfs_inode *);
+void pnfs_destroy_all_layouts(struct nfs_client *);
+void put_layout_hdr(struct pnfs_layout_hdr *lo);
+void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
+                             const nfs4_stateid *new,
+                             bool update_barrier);
+int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
+                                  struct pnfs_layout_hdr *lo,
+                                  struct nfs4_state *open_state);
+int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
+                                struct list_head *tmp_list,
+                                struct pnfs_layout_range *recall_range);
+bool pnfs_roc(struct inode *ino);
+void pnfs_roc_release(struct inode *ino);
+void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
+bool pnfs_roc_drain(struct inode *ino, u32 *barrier);
+void pnfs_set_layoutcommit(struct nfs_write_data *wdata);
+int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
+int _pnfs_return_layout(struct inode *);
+int pnfs_ld_write_done(struct nfs_write_data *);
+int pnfs_ld_read_done(struct nfs_read_data *);
+
+/* pnfs_dev.c */
+struct nfs4_deviceid_node {
+        struct hlist_node               node;
+        struct hlist_node               tmpnode;
+        const struct pnfs_layoutdriver_type *ld;
+        const struct nfs_client         *nfs_client;
+        struct nfs4_deviceid            deviceid;
+        atomic_t                        ref;
+};
+
+void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
+struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
+struct nfs4_deviceid_node *nfs4_unhash_put_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
+void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
+void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
+                             const struct pnfs_layoutdriver_type *,
+                             const struct nfs_client *,
+                             const struct nfs4_deviceid *);
+struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *);
+bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
+void nfs4_deviceid_purge_client(const struct nfs_client *);
+
+static inline int lo_fail_bit(u32 iomode)
+{
+        return iomode == IOMODE_RW ?
+                         NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
+}
+
+static inline struct pnfs_layout_segment *
+get_lseg(struct pnfs_layout_segment *lseg)
+{
+        if (lseg) {
+                atomic_inc(&lseg->pls_refcount);
+                smp_mb__after_atomic_inc();
+        }
+        return lseg;
+}
+
+/* Return true if a layout driver is being used for this mountpoint */
+static inline int pnfs_enabled_sb(struct nfs_server *nfss)
+{
+        return nfss->pnfs_curr_ld != NULL;
+}
+
+static inline void
+pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
+{
+        if (lseg) {
+                struct pnfs_layoutdriver_type *ld;
+
+                ld = NFS_SERVER(req->wb_page->mapping->host)->pnfs_curr_ld;
+                if (ld->mark_pnfs_commit && ld->mark_pnfs_commit(lseg)) {
+                        set_bit(PG_PNFS_COMMIT, &req->wb_flags);
+                        req->wb_commit_lseg = get_lseg(lseg);
+                }
+        }
+}
+
+static inline int
+pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
+{
+        if (!test_and_clear_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags))
+                return PNFS_NOT_ATTEMPTED;
+        return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how);
+}
+
+static inline struct list_head *
+pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
+{
+        struct list_head *rv;
+
+        if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags)) {
+                struct inode *inode = req->wb_commit_lseg->pls_layout->plh_inode;
+
+                set_bit(NFS_INO_PNFS_COMMIT, &NFS_I(inode)->flags);
+                rv = NFS_SERVER(inode)->pnfs_curr_ld->choose_commit_list(req);
+                /* matched by ref taken when PG_PNFS_COMMIT is set */
+                put_lseg(req->wb_commit_lseg);
+        } else
+                rv = mds;
+        return rv;
+}
+
+static inline void pnfs_clear_request_commit(struct nfs_page *req)
+{
+        if (test_and_clear_bit(PG_PNFS_COMMIT, &req->wb_flags))
+                put_lseg(req->wb_commit_lseg);
+}
+
+/* Should the pNFS client commit and return the layout upon a setattr */
+static inline bool
+pnfs_ld_layoutret_on_setattr(struct inode *inode)
+{
+        if (!pnfs_enabled_sb(NFS_SERVER(inode)))
+                return false;
+        return NFS_SERVER(inode)->pnfs_curr_ld->flags &
+                PNFS_LAYOUTRET_ON_SETATTR;
+}
+
+static inline int pnfs_return_layout(struct inode *ino)
+{
+        struct nfs_inode *nfsi = NFS_I(ino);
+        struct nfs_server *nfss = NFS_SERVER(ino);
+
+        if (pnfs_enabled_sb(nfss) && nfsi->layout)
+                return _pnfs_return_layout(ino);
+
+        return 0;
+}
+
+static inline void pnfs_pageio_init(struct nfs_pageio_descriptor *pgio,
+                                    struct inode *inode)
+{
+        struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
+
+        if (ld)
+                pgio->pg_test = ld->pg_test;
+}
+
+#else  /* CONFIG_NFS_V4_1 */
+
+static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
+{
+}
+
+static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
+{
+}
+
+static inline struct pnfs_layout_segment *
+get_lseg(struct pnfs_layout_segment *lseg)
+{
+        return NULL;
+}
+
+static inline void put_lseg(struct pnfs_layout_segment *lseg)
+{
+}
+
+static inline struct pnfs_layout_segment *
+pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
+                   loff_t pos, u64 count, enum pnfs_iomode access_type,
+                   gfp_t gfp_flags)
+{
+        return NULL;
+}
+
+static inline enum pnfs_try_status
+pnfs_try_to_read_data(struct nfs_read_data *data,
+                      const struct rpc_call_ops *call_ops)
+{
+        return PNFS_NOT_ATTEMPTED;
+}
+
+static inline enum pnfs_try_status
+pnfs_try_to_write_data(struct nfs_write_data *data,
+                       const struct rpc_call_ops *call_ops, int how)
+{
+        return PNFS_NOT_ATTEMPTED;
+}
+
+static inline int pnfs_return_layout(struct inode *ino)
+{
+        return 0;
+}
+
+static inline bool
+pnfs_ld_layoutret_on_setattr(struct inode *inode)
+{
+        return false;
+}
+
+static inline bool
+pnfs_roc(struct inode *ino)
+{
+        return false;
+}
+
+static inline void
+pnfs_roc_release(struct inode *ino)
+{
+}
+
+static inline void
+pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
+{
+}
+
+static inline bool
+pnfs_roc_drain(struct inode *ino, u32 *barrier)
+{
+        return false;
+}
+
+static inline void set_pnfs_layoutdriver(struct nfs_server *s, u32 id)
+{
+}
+
+static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
+{
+}
+
+static inline void pnfs_pageio_init(struct nfs_pageio_descriptor *pgio,
+                                    struct inode *inode)
+{
+}
+
+static inline void
+pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg)
+{
+}
+
+static inline int
+pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how)
+{
+        return PNFS_NOT_ATTEMPTED;
+}
+
+static inline struct list_head *
+pnfs_choose_commit_list(struct nfs_page *req, struct list_head *mds)
+{
+        return mds;
+}
+
+static inline void pnfs_clear_request_commit(struct nfs_page *req)
+{
+}
+
+static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
+{
+        return 0;
+}
+
+static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl)
+{
+}
+#endif /* CONFIG_NFS_V4_1 */
+
+#endif /* FS_NFS_PNFS_H */