/* SPDX-License-Identifier: GPL-2.0 */
/*
 * NFS internal definitions
 */

#include "nfs4_fs.h"
#include <linux/fs_context.h>
#include <linux/security.h>
#include <linux/compiler_attributes.h>
#include <linux/crc32.h>
#include <linux/sunrpc/addr.h>
#include <linux/nfs_page.h>
#include <linux/nfslocalio.h>
#include <linux/wait_bit.h>

#define NFS_SB_MASK (SB_RDONLY|SB_NOSUID|SB_NODEV|SB_NOEXEC|SB_SYNCHRONOUS)

extern const struct export_operations nfs_export_ops;

struct nfs_string;
struct nfs_pageio_descriptor;

static inline void nfs_attr_check_mountpoint(struct super_block *parent, struct nfs_fattr *fattr)
{
        if (!nfs_fsid_equal(&NFS_SB(parent)->fsid, &fattr->fsid))
                fattr->valid |= NFS_ATTR_FATTR_MOUNTPOINT;
}

static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)
{
        if (((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) == 0) ||
            (((fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT) == 0) &&
             ((fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) == 0)))
                return 0;
        return 1;
}

static inline bool nfs_lookup_is_soft_revalidate(const struct dentry *dentry)
{
        if (!(NFS_SB(dentry->d_sb)->flags & NFS_MOUNT_SOFTREVAL))
                return false;
        if (!d_is_positive(dentry) || !NFS_FH(d_inode(dentry))->size)
                return false;
        return true;
}

static inline fmode_t flags_to_mode(int flags)
{
        fmode_t res = (__force fmode_t)flags & FMODE_EXEC;
        if ((flags & O_ACCMODE) != O_WRONLY)
                res |= FMODE_READ;
        if ((flags & O_ACCMODE) != O_RDONLY)
                res |= FMODE_WRITE;
        return res;
}

/*
 * Note: RFC 1813 doesn't limit the number of auth flavors that
 * a server can return, so make something up.
 */
#define NFS_MAX_SECFLAVORS      (12)

/*
 * Value used if the user did not specify a port value.
 */
#define NFS_UNSPEC_PORT         (-1)

#define NFS_UNSPEC_RETRANS      (UINT_MAX)
#define NFS_UNSPEC_TIMEO        (UINT_MAX)

struct nfs_client_initdata {
        unsigned long init_flags;
        const char *hostname;                   /* Hostname of the server */
        const struct sockaddr_storage *addr;    /* Address of the server */
        const char *nodename;                   /* Hostname of the client */
        const char *ip_addr;                    /* IP address of the client */
        size_t addrlen;
        struct nfs_subversion *nfs_mod;
        int proto;
        u32 minorversion;
        unsigned int nconnect;
        unsigned int max_connect;
        struct net *net;
        const struct rpc_timeout *timeparms;
        const struct cred *cred;
        struct xprtsec_parms xprtsec;
        unsigned long connect_timeout;
        unsigned long reconnect_timeout;
};

/*
 * In-kernel mount arguments
 */
struct nfs_fs_context {
        bool                    internal;
        bool                    skip_reconfig_option_check;
        bool                    need_mount;
        bool                    sloppy;
        unsigned int            flags;          /* NFS{,4}_MOUNT_* flags */
        unsigned int            rsize, wsize;
        unsigned int            timeo, retrans;
        unsigned int            acregmin, acregmax;
        unsigned int            acdirmin, acdirmax;
        unsigned int            namlen;
        unsigned int            options;
        unsigned int            bsize;
        struct nfs_auth_info    auth_info;
        rpc_authflavor_t        selected_flavor;
        struct xprtsec_parms    xprtsec;
        char                    *client_address;
        unsigned int            version;
        unsigned int            minorversion;
        char                    *fscache_uniq;
        unsigned short          protofamily;
        unsigned short          mountfamily;
        bool                    has_sec_mnt_opts;
        int                     lock_status;

        struct {
                union {
                        struct sockaddr address;
                        struct sockaddr_storage _address;
                };
                size_t                  addrlen;
                char                    *hostname;
                u32                     version;
                int                     port;
                unsigned short          protocol;
        } mount_server;

        struct {
                union {
                        struct sockaddr address;
                        struct sockaddr_storage _address;
                };
                size_t                  addrlen;
                char                    *hostname;
                char                    *export_path;
                int                     port;
                unsigned short          protocol;
                unsigned short          nconnect;
                unsigned short          max_connect;
                unsigned short          export_path_len;
        } nfs_server;

        struct nfs_fh           *mntfh;
        struct nfs_server       *server;
        struct nfs_subversion   *nfs_mod;

        /* Information for a cloned mount. */
        struct nfs_clone_mount {
                struct super_block      *sb;
                struct dentry           *dentry;
                struct nfs_fattr        *fattr;
        } clone_data;
};

enum nfs_lock_status {
        NFS_LOCK_NOT_SET        = 0,
        NFS_LOCK_LOCK           = 1,
        NFS_LOCK_NOLOCK         = 2,
};

#define nfs_errorf(fc, fmt, ...) ((fc)->log.log ?               \
        errorf(fc, fmt, ## __VA_ARGS__) :                       \
        ({ dprintk(fmt "\n", ## __VA_ARGS__); }))

#define nfs_ferrorf(fc, fac, fmt, ...) ((fc)->log.log ?         \
        errorf(fc, fmt, ## __VA_ARGS__) :                       \
        ({ dfprintk(fac, fmt "\n", ## __VA_ARGS__); }))

#define nfs_invalf(fc, fmt, ...) ((fc)->log.log ?               \
        invalf(fc, fmt, ## __VA_ARGS__) :                       \
        ({ dprintk(fmt "\n", ## __VA_ARGS__);  -EINVAL; }))

#define nfs_finvalf(fc, fac, fmt, ...) ((fc)->log.log ?         \
        invalf(fc, fmt, ## __VA_ARGS__) :                       \
        ({ dfprintk(fac, fmt "\n", ## __VA_ARGS__);  -EINVAL; }))

#define nfs_warnf(fc, fmt, ...) ((fc)->log.log ?                \
        warnf(fc, fmt, ## __VA_ARGS__) :                        \
        ({ dprintk(fmt "\n", ## __VA_ARGS__); }))

#define nfs_fwarnf(fc, fac, fmt, ...) ((fc)->log.log ?          \
        warnf(fc, fmt, ## __VA_ARGS__) :                        \
        ({ dfprintk(fac, fmt "\n", ## __VA_ARGS__); }))

static inline struct nfs_fs_context *nfs_fc2context(const struct fs_context *fc)
{
        return fc->fs_private;
}

/* mount_clnt.c */
struct nfs_mount_request {
        struct sockaddr_storage *sap;
        size_t                  salen;
        char                    *hostname;
        char                    *dirpath;
        u32                     version;
        unsigned short          protocol;
        struct nfs_fh           *fh;
        int                     noresvport;
        unsigned int            *auth_flav_len;
        rpc_authflavor_t        *auth_flavs;
        struct net              *net;
};

extern int nfs_mount(struct nfs_mount_request *info, int timeo, int retrans);

/* client.c */
extern const struct rpc_program nfs_program;
extern void nfs_clients_init(struct net *net);
extern void nfs_clients_exit(struct net *net);
extern struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *);
int nfs_create_rpc_client(struct nfs_client *, const struct nfs_client_initdata *, rpc_authflavor_t);
struct nfs_client *nfs_get_client(const struct nfs_client_initdata *);
int nfs_probe_server(struct nfs_server *, struct nfs_fh *);
void nfs_server_insert_lists(struct nfs_server *);
void nfs_server_remove_lists(struct nfs_server *);
void nfs_init_timeout_values(struct rpc_timeout *to, int proto, int timeo, int retrans);
int nfs_init_server_rpcclient(struct nfs_server *, const struct rpc_timeout *t,
                rpc_authflavor_t);
struct nfs_server *nfs_alloc_server(void);
void nfs_server_copy_userdata(struct nfs_server *, struct nfs_server *);

extern void nfs_put_client(struct nfs_client *);
extern void nfs_free_client(struct nfs_client *);
extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
extern struct nfs_client *
nfs4_find_client_sessionid(struct net *, const struct sockaddr *,
                                struct nfs4_sessionid *, u32);
extern struct nfs_server *nfs_create_server(struct fs_context *);
extern void nfs_server_set_init_caps(struct nfs_server *);
extern struct nfs_server *nfs4_create_server(struct fs_context *);
extern struct nfs_server *nfs4_create_referral_server(struct fs_context *);
extern int nfs4_update_server(struct nfs_server *server, const char *hostname,
                                        struct sockaddr_storage *sap, size_t salen,
                                        struct net *net);
extern void nfs_free_server(struct nfs_server *server);
extern struct nfs_server *nfs_clone_server(struct nfs_server *,
                                           struct nfs_fh *,
                                           struct nfs_fattr *,
                                           rpc_authflavor_t);
extern bool nfs_client_init_is_complete(const struct nfs_client *clp);
extern int nfs_client_init_status(const struct nfs_client *clp);
extern int nfs_wait_client_init_complete(const struct nfs_client *clp);
extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
extern struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
                                             const struct sockaddr_storage *ds_addr,
                                             int ds_addrlen, int ds_proto,
                                             unsigned int ds_timeo,
                                             unsigned int ds_retrans,
                                             u32 minor_version);
extern struct rpc_clnt *nfs4_find_or_create_ds_client(struct nfs_client *,
                                                struct inode *);
extern struct nfs_client *nfs3_set_ds_client(struct nfs_server *mds_srv,
                        const struct sockaddr_storage *ds_addr, int ds_addrlen,
                        int ds_proto, unsigned int ds_timeo,
                        unsigned int ds_retrans);
#ifdef CONFIG_PROC_FS
extern int __init nfs_fs_proc_init(void);
extern void nfs_fs_proc_exit(void);
extern int nfs_fs_proc_net_init(struct net *net);
extern void nfs_fs_proc_net_exit(struct net *net);
#else
static inline int nfs_fs_proc_net_init(struct net *net)
{
        return 0;
}
static inline void nfs_fs_proc_net_exit(struct net *net)
{
}
static inline int nfs_fs_proc_init(void)
{
        return 0;
}
static inline void nfs_fs_proc_exit(void)
{
}
#endif

/* callback_xdr.c */
extern const struct svc_version nfs4_callback_version1;
extern const struct svc_version nfs4_callback_version4;

/* fs_context.c */
extern struct file_system_type nfs_fs_type;

/* pagelist.c */
extern int __init nfs_init_nfspagecache(void);
extern void nfs_destroy_nfspagecache(void);
extern int __init nfs_init_readpagecache(void);
extern void nfs_destroy_readpagecache(void);
extern int __init nfs_init_writepagecache(void);
extern void nfs_destroy_writepagecache(void);

extern int __init nfs_init_directcache(void);
extern void nfs_destroy_directcache(void);
extern void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
                              struct nfs_pgio_header *hdr,
                              void (*release)(struct nfs_pgio_header *hdr));
void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos);
int nfs_iocounter_wait(struct nfs_lock_context *l_ctx);

extern const struct nfs_pageio_ops nfs_pgio_rw_ops;
struct nfs_pgio_header *nfs_pgio_header_alloc(const struct nfs_rw_ops *);
void nfs_pgio_header_free(struct nfs_pgio_header *);
int nfs_generic_pgio(struct nfs_pageio_descriptor *, struct nfs_pgio_header *);
int nfs_initiate_pgio(struct rpc_clnt *clnt, struct nfs_pgio_header *hdr,
                      const struct cred *cred, const struct nfs_rpc_ops *rpc_ops,
                      const struct rpc_call_ops *call_ops, int how, int flags,
                      struct nfsd_file *localio);
void nfs_free_request(struct nfs_page *req);
struct nfs_pgio_mirror *
nfs_pgio_current_mirror(struct nfs_pageio_descriptor *desc);

static inline bool nfs_match_open_context(const struct nfs_open_context *ctx1,
                const struct nfs_open_context *ctx2)
{
        return cred_fscmp(ctx1->cred, ctx2->cred) == 0 && ctx1->state == ctx2->state;
}

/* nfs2xdr.c */
extern const struct rpc_procinfo nfs_procedures[];
extern int nfs2_decode_dirent(struct xdr_stream *,
                                struct nfs_entry *, bool);

/* nfs3xdr.c */
extern const struct rpc_procinfo nfs3_procedures[];
extern int nfs3_decode_dirent(struct xdr_stream *,
                                struct nfs_entry *, bool);

/* nfs4xdr.c */
#if IS_ENABLED(CONFIG_NFS_V4)
extern int nfs4_decode_dirent(struct xdr_stream *,
                                struct nfs_entry *, bool);
extern const u32 nfs41_maxread_overhead;
extern const u32 nfs41_maxwrite_overhead;
extern const u32 nfs41_maxgetdevinfo_overhead;

/* nfs4proc.c */
extern const struct rpc_procinfo nfs4_procedures[];
#endif /* CONFIG_NFS_V4 */

#ifdef CONFIG_NFS_V4_SECURITY_LABEL
extern struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags);
static inline struct nfs4_label *
nfs4_label_copy(struct nfs4_label *dst, struct nfs4_label *src)
{
        if (!dst || !src)
                return NULL;

        if (src->len > NFS4_MAXLABELLEN)
                return NULL;

        dst->lfs = src->lfs;
        dst->pi = src->pi;
        dst->len = src->len;
        memcpy(dst->label, src->label, src->len);

        return dst;
}

static inline void nfs_zap_label_cache_locked(struct nfs_inode *nfsi)
{
        if (nfs_server_capable(&nfsi->vfs_inode, NFS_CAP_SECURITY_LABEL))
                nfsi->cache_validity |= NFS_INO_INVALID_LABEL;
}
#else
static inline struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags) { return NULL; }
static inline void nfs_zap_label_cache_locked(struct nfs_inode *nfsi)
{
}
static inline struct nfs4_label *
nfs4_label_copy(struct nfs4_label *dst, struct nfs4_label *src)
{
        return NULL;
}
#endif /* CONFIG_NFS_V4_SECURITY_LABEL */

/* proc.c */
void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
                           const struct nfs_client_initdata *);

/* dir.c */
extern void nfs_readdir_record_entry_cache_hit(struct inode *dir);
extern void nfs_readdir_record_entry_cache_miss(struct inode *dir);
extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
                                            struct shrink_control *sc);
extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
                                           struct shrink_control *sc);
struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
void nfs_d_prune_case_insensitive_aliases(struct inode *inode);
int nfs_create(struct mnt_idmap *, struct inode *, struct dentry *,
               umode_t, bool);
struct dentry *nfs_mkdir(struct mnt_idmap *, struct inode *, struct dentry *,
                         umode_t);
int nfs_rmdir(struct inode *, struct dentry *);
int nfs_unlink(struct inode *, struct dentry *);
int nfs_symlink(struct mnt_idmap *, struct inode *, struct dentry *,
                const char *);
int nfs_link(struct dentry *, struct inode *, struct dentry *);
int nfs_mknod(struct mnt_idmap *, struct inode *, struct dentry *, umode_t,
              dev_t);
int nfs_rename(struct mnt_idmap *, struct inode *, struct dentry *,
               struct inode *, struct dentry *, unsigned int);

#ifdef CONFIG_NFS_V4_2
static inline __u32 nfs_access_xattr_mask(const struct nfs_server *server)
{
        if (!(server->caps & NFS_CAP_XATTR))
                return 0;
        return NFS4_ACCESS_XAREAD | NFS4_ACCESS_XAWRITE | NFS4_ACCESS_XALIST;
}
#else
static inline __u32 nfs_access_xattr_mask(const struct nfs_server *server)
{
        return 0;
}
#endif

/* file.c */
int nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
loff_t nfs_file_llseek(struct file *, loff_t, int);
ssize_t nfs_file_read(struct kiocb *, struct iov_iter *);
ssize_t nfs_file_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe,
                             size_t len, unsigned int flags);
int nfs_file_mmap_prepare(struct vm_area_desc *);
ssize_t nfs_file_write(struct kiocb *, struct iov_iter *);
int nfs_file_release(struct inode *, struct file *);
int nfs_lock(struct file *, int, struct file_lock *);
int nfs_flock(struct file *, int, struct file_lock *);
int nfs_check_flags(int);
void nfs_truncate_last_folio(struct address_space *mapping, loff_t from,
                             loff_t to);

/* inode.c */
extern struct workqueue_struct *nfsiod_workqueue;
extern struct workqueue_struct *nfslocaliod_workqueue;
extern struct inode *nfs_alloc_inode(struct super_block *sb);
extern void nfs_free_inode(struct inode *);
extern int nfs_write_inode(struct inode *, struct writeback_control *);
extern int nfs_drop_inode(struct inode *);
extern void nfs_clear_inode(struct inode *);
extern void nfs_evict_inode(struct inode *);
extern void nfs_zap_acl_cache(struct inode *inode);
extern void nfs_set_cache_invalid(struct inode *inode, unsigned long flags);
extern bool nfs_check_cache_invalid(struct inode *, unsigned long);
extern int nfs_wait_bit_killable(struct wait_bit_key *key, int mode);

#if IS_ENABLED(CONFIG_NFS_LOCALIO)
/* localio.c */
struct nfs_local_dio {
        u32 mem_align;
        u32 offset_align;
        loff_t middle_offset;
        loff_t end_offset;
        ssize_t start_len;      /* Length for misaligned first extent */
        ssize_t middle_len;     /* Length for DIO-aligned middle extent */
        ssize_t end_len;        /* Length for misaligned last extent */
};

extern void nfs_local_probe_async(struct nfs_client *);
extern void nfs_local_probe_async_work(struct work_struct *);
extern struct nfsd_file *nfs_local_open_fh(struct nfs_client *,
                                           const struct cred *,
                                           struct nfs_fh *,
                                           struct nfs_file_localio *,
                                           const fmode_t);
extern int nfs_local_doio(struct nfs_client *,
                          struct nfsd_file *,
                          struct nfs_pgio_header *,
                          const struct rpc_call_ops *);
extern int nfs_local_commit(struct nfsd_file *,
                            struct nfs_commit_data *,
                            const struct rpc_call_ops *, int);
extern bool nfs_server_is_local(const struct nfs_client *clp);

#else /* CONFIG_NFS_LOCALIO */
static inline void nfs_local_probe(struct nfs_client *clp) {}
static inline void nfs_local_probe_async(struct nfs_client *clp) {}
static inline struct nfsd_file *
nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred,
                  struct nfs_fh *fh, struct nfs_file_localio *nfl,
                  const fmode_t mode)
{
        return NULL;
}
static inline int nfs_local_doio(struct nfs_client *clp,
                                 struct nfsd_file *localio,
                                 struct nfs_pgio_header *hdr,
                                 const struct rpc_call_ops *call_ops)
{
        return -EINVAL;
}
static inline int nfs_local_commit(struct nfsd_file *localio,
                                struct nfs_commit_data *data,
                                const struct rpc_call_ops *call_ops, int how)
{
        return -EINVAL;
}
static inline bool nfs_server_is_local(const struct nfs_client *clp)
{
        return false;
}
#endif /* CONFIG_NFS_LOCALIO */

/* super.c */
extern const struct super_operations nfs_sops;
bool nfs_auth_info_match(const struct nfs_auth_info *, rpc_authflavor_t);
int nfs_try_get_tree(struct fs_context *);
int nfs_get_tree_common(struct fs_context *);
void nfs_kill_super(struct super_block *);

extern int __init register_nfs_fs(void);
extern void __exit unregister_nfs_fs(void);
extern bool nfs_sb_active(struct super_block *sb);
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 __must_check int nfs_start_io_read(struct inode *inode);
extern void nfs_end_io_read(struct inode *inode);
extern  __must_check int nfs_start_io_write(struct inode *inode);
extern void nfs_end_io_write(struct inode *inode);
extern __must_check int nfs_start_io_direct(struct inode *inode);
extern void nfs_end_io_direct(struct inode *inode);

static inline bool nfs_file_io_is_buffered(struct nfs_inode *nfsi)
{
        return test_bit(NFS_INO_ODIRECT, &nfsi->flags) == 0;
}

/* Must be called with exclusively locked inode->i_rwsem */
static inline void nfs_file_block_o_direct(struct nfs_inode *nfsi)
{
        if (test_bit(NFS_INO_ODIRECT, &nfsi->flags)) {
                clear_bit(NFS_INO_ODIRECT, &nfsi->flags);
                inode_dio_wait(&nfsi->vfs_inode);
        }
}


/* namespace.c */
#define NFS_PATH_CANONICAL 1
extern char *nfs_path(char **p, struct dentry *dentry,
                      char *buffer, ssize_t buflen, unsigned flags);
extern struct vfsmount *nfs_d_automount(struct path *path);
int nfs_submount(struct fs_context *, struct nfs_server *);
int nfs_do_submount(struct fs_context *);

/* getroot.c */
extern int nfs_get_root(struct super_block *s, struct fs_context *fc);
#if IS_ENABLED(CONFIG_NFS_V4)
extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh, bool);
#endif

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 bool nfs_read_alloc_scratch(struct nfs_pgio_header *hdr, size_t size);
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_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);

/* super.c */
void nfs_umount_begin(struct super_block *);
int  nfs_statfs(struct dentry *, struct kstatfs *);
int  nfs_show_options(struct seq_file *, struct dentry *);
int  nfs_show_devname(struct seq_file *, struct dentry *);
int  nfs_show_path(struct seq_file *, struct dentry *);
int  nfs_show_stats(struct seq_file *, struct dentry *);
int  nfs_reconfigure(struct fs_context *);

/* write.c */
extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
                        struct inode *inode, int ioflags, bool force_mds,
                        const struct nfs_pgio_completion_ops *compl_ops);
extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
extern void nfs_commit_free(struct nfs_commit_data *p);
extern void nfs_commit_prepare(struct rpc_task *task, void *calldata);
extern int nfs_initiate_commit(struct rpc_clnt *clnt,
                               struct nfs_commit_data *data,
                               const struct nfs_rpc_ops *nfs_ops,
                               const struct rpc_call_ops *call_ops,
                               int how, int flags,
                               struct nfsd_file *localio);
extern void nfs_init_commit(struct nfs_commit_data *data,
                            struct list_head *head,
                            struct pnfs_layout_segment *lseg,
                            struct nfs_commit_info *cinfo);
int nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
                         struct nfs_commit_info *cinfo, int max);
unsigned long nfs_reqs_to_commit(struct nfs_commit_info *);
int nfs_scan_commit(struct inode *inode, struct list_head *dst,
                    struct nfs_commit_info *cinfo);
void nfs_mark_request_commit(struct nfs_page *req,
                             struct pnfs_layout_segment *lseg,
                             struct nfs_commit_info *cinfo,
                             u32 ds_commit_idx);
int nfs_write_need_commit(struct nfs_pgio_header *);
void nfs_writeback_update_inode(struct nfs_pgio_header *hdr);
int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
                            int how, struct nfs_commit_info *cinfo);
void nfs_retry_commit(struct list_head *page_list,
                      struct pnfs_layout_segment *lseg,
                      struct nfs_commit_info *cinfo,
                      u32 ds_commit_idx);
void nfs_commitdata_release(struct nfs_commit_data *data);
void nfs_request_add_commit_list(struct nfs_page *req,
                                 struct nfs_commit_info *cinfo);
void nfs_request_add_commit_list_locked(struct nfs_page *req,
                struct list_head *dst,
                struct nfs_commit_info *cinfo);
void nfs_request_remove_commit_list(struct nfs_page *req,
                                    struct nfs_commit_info *cinfo);
void nfs_init_cinfo(struct nfs_commit_info *cinfo,
                    struct inode *inode,
                    struct nfs_direct_req *dreq);
int nfs_key_timeout_notify(struct file *filp, struct inode *inode);
bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx, struct inode *inode);
void nfs_pageio_stop_mirroring(struct nfs_pageio_descriptor *pgio);

int nfs_filemap_write_and_wait_range(struct address_space *mapping,
                loff_t lstart, loff_t lend);

#ifdef CONFIG_NFS_V4
static inline void
pnfs_bucket_clear_pnfs_ds_commit_verifiers(struct pnfs_commit_bucket *buckets,
                unsigned int nbuckets)
{
        unsigned int i;

        for (i = 0; i < nbuckets; i++)
                buckets[i].direct_verf.committed = NFS_INVALID_STABLE_HOW;
}
static inline
void nfs_clear_pnfs_ds_commit_verifiers(struct pnfs_ds_commit_info *cinfo)
{
        struct pnfs_commit_array *array;

        rcu_read_lock();
        list_for_each_entry_rcu(array, &cinfo->commits, cinfo_list)
                pnfs_bucket_clear_pnfs_ds_commit_verifiers(array->buckets,
                                array->nbuckets);
        rcu_read_unlock();
}
#else /* CONFIG_NFS_V4 */
static inline
void nfs_clear_pnfs_ds_commit_verifiers(struct pnfs_ds_commit_info *cinfo)
{
}
#endif /* CONFIG_NFS_V4 */

#ifdef CONFIG_MIGRATION
int nfs_migrate_folio(struct address_space *, struct folio *dst,
                struct folio *src, enum migrate_mode);
#else
#define nfs_migrate_folio NULL
#endif

static inline int
nfs_write_verifier_cmp(const struct nfs_write_verifier *v1,
                const struct nfs_write_verifier *v2)
{
        return memcmp(v1->data, v2->data, sizeof(v1->data));
}

static inline bool
nfs_write_match_verf(const struct nfs_writeverf *verf,
                struct nfs_page *req)
{
        return verf->committed > NFS_UNSTABLE &&
                !nfs_write_verifier_cmp(&req->wb_verf, &verf->verifier);
}

static inline gfp_t nfs_io_gfp_mask(void)
{
        gfp_t ret = current_gfp_context(GFP_KERNEL);

        /* For workers __GFP_NORETRY only with __GFP_IO or __GFP_FS */
        if ((current->flags & PF_WQ_WORKER) && ret == GFP_KERNEL)
                ret |= __GFP_NORETRY | __GFP_NOWARN;
        return ret;
}

/*
 * Special version of should_remove_suid() that ignores capabilities.
 */
static inline int nfs_should_remove_suid(const struct inode *inode)
{
        umode_t mode = inode->i_mode;
        int kill = 0;

        /* suid always must be killed */
        if (unlikely(mode & S_ISUID))
                kill = ATTR_KILL_SUID;

        /*
         * sgid without any exec bits is just a mandatory locking mark; leave
         * it alone.  If some exec bits are set, it's a real sgid; kill it.
         */
        if (unlikely((mode & S_ISGID) && (mode & S_IXGRP)))
                kill |= ATTR_KILL_SGID;

        if (unlikely(kill && S_ISREG(mode)))
                return kill;

        return 0;
}

/* unlink.c */
extern struct rpc_task *
nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
                 struct dentry *old_dentry, struct dentry *new_dentry,
                 void (*complete)(struct rpc_task *, struct nfs_renamedata *));
extern int nfs_sillyrename(struct inode *dir, struct dentry *dentry);

/* direct.c */
void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
                              struct nfs_direct_req *dreq);
extern ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq, loff_t offset);

/* nfs4proc.c */
extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
                            const struct nfs_client_initdata *);
extern int nfs41_walk_client_list(struct nfs_client *clp,
                                struct nfs_client **result,
                                const struct cred *cred);
extern void nfs4_test_session_trunk(struct rpc_clnt *clnt,
                                struct rpc_xprt *xprt,
                                void *data);

static inline struct inode *nfs_igrab_and_active(struct inode *inode)
{
        struct super_block *sb = inode->i_sb;

        if (sb && nfs_sb_active(sb)) {
                if (igrab(inode))
                        return inode;
                nfs_sb_deactive(sb);
        }
        return NULL;
}

static inline void nfs_iput_and_deactive(struct inode *inode)
{
        if (inode != NULL) {
                struct super_block *sb = inode->i_sb;

                iput(inode);
                nfs_sb_deactive(sb);
        }
}

/*
 * Determine the device name as a string
 */
static inline char *nfs_devname(struct dentry *dentry,
                                char *buffer, ssize_t buflen)
{
        char *dummy;
        return nfs_path(&dummy, dentry, buffer, buflen, NFS_PATH_CANONICAL);
}

/*
 * Determine the actual block size (and log2 thereof)
 */
static inline
unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
{
        /* make sure blocksize is a power of two */
        if ((bsize & (bsize - 1)) || nrbitsp) {
                unsigned char   nrbits;

                for (nrbits = 31; nrbits && !(bsize & (1UL << nrbits)); nrbits--)
                        ;
                bsize = 1UL << nrbits;
                if (nrbitsp)
                        *nrbitsp = nrbits;
        }

        return bsize;
}

/*
 * Calculate the number of 512byte blocks used.
 */
static inline blkcnt_t nfs_calc_block_size(u64 tsize)
{
        blkcnt_t used = (tsize + 511) >> 9;
        return (used > ULONG_MAX) ? ULONG_MAX : used;
}

/*
 * Compute and set NFS server blocksize
 */
static inline
unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
{
        if (bsize < NFS_MIN_FILE_IO_SIZE)
                bsize = NFS_DEF_FILE_IO_SIZE;
        else if (bsize >= NFS_MAX_FILE_IO_SIZE)
                bsize = NFS_MAX_FILE_IO_SIZE;

        return nfs_block_bits(bsize, nrbitsp);
}

/*
 * Compute and set NFS server rsize / wsize
 */
static inline
unsigned long nfs_io_size(unsigned long iosize, enum xprt_transports proto)
{
        if (iosize < NFS_MIN_FILE_IO_SIZE)
                iosize = NFS_DEF_FILE_IO_SIZE;
        else if (iosize >= NFS_MAX_FILE_IO_SIZE)
                iosize = NFS_MAX_FILE_IO_SIZE;

        if (proto == XPRT_TRANSPORT_UDP || iosize < PAGE_SIZE)
                return nfs_block_bits(iosize, NULL);
        return iosize & PAGE_MASK;
}

/*
 * Determine the maximum file size for a superblock
 */
static inline
void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
{
        sb->s_maxbytes = (loff_t)maxfilesize;
        if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0)
                sb->s_maxbytes = MAX_LFS_FILESIZE;
}

/*
 * Record the page as unstable (an extra writeback period) and mark its
 * inode as dirty.
 */
static inline void nfs_folio_mark_unstable(struct folio *folio,
                                           struct nfs_commit_info *cinfo)
{
        if (folio && !cinfo->dreq) {
                struct inode *inode = folio->mapping->host;
                long nr = folio_nr_pages(folio);

                /* This page is really still in write-back - just that the
                 * writeback is happening on the server now.
                 */
                node_stat_mod_folio(folio, NR_WRITEBACK, nr);
                wb_stat_mod(&inode_to_bdi(inode)->wb, WB_WRITEBACK, nr);
                __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
        }
}

/*
 * Determine the number of bytes of data the page contains
 */
static inline size_t nfs_folio_length(struct folio *folio)
{
        loff_t i_size = i_size_read(folio->mapping->host);

        if (i_size > 0) {
                pgoff_t index = folio->index >> folio_order(folio);
                pgoff_t end_index = (i_size - 1) >> folio_shift(folio);
                if (index < end_index)
                        return folio_size(folio);
                if (index == end_index)
                        return offset_in_folio(folio, i_size - 1) + 1;
        }
        return 0;
}

/*
 * Convert a umode to a dirent->d_type
 */
static inline
unsigned char nfs_umode_to_dtype(umode_t mode)
{
        return (mode >> 12) & 15;
}

/*
 * Determine the number of pages in an array of length 'len' and
 * with a base offset of 'base'
 */
static inline unsigned int nfs_page_array_len(unsigned int base, size_t len)
{
        return ((unsigned long)len + (unsigned long)base + PAGE_SIZE - 1) >>
               PAGE_SHIFT;
}

/*
 * Convert a struct timespec64 into a 64-bit change attribute
 *
 * This does approximately the same thing as timespec64_to_ns(),
 * but for calculation efficiency, we multiply the seconds by
 * 1024*1024*1024.
 */
static inline
u64 nfs_timespec_to_change_attr(const struct timespec64 *ts)
{
        return ((u64)ts->tv_sec << 30) + ts->tv_nsec;
}

static inline u32 nfs_stateid_hash(const nfs4_stateid *stateid)
{
        return ~crc32_le(0xFFFFFFFF, &stateid->other[0],
                                NFS4_STATEID_OTHER_SIZE);
}

static inline bool nfs_current_task_exiting(void)
{
        return (current->flags & PF_EXITING) != 0;
}

static inline bool nfs_error_is_fatal(int err)
{
        switch (err) {
        case -ERESTARTSYS:
        case -EINTR:
        case -EACCES:
        case -EDQUOT:
        case -EFBIG:
        case -EIO:
        case -ENOSPC:
        case -EROFS:
        case -ESTALE:
        case -E2BIG:
        case -ENOMEM:
        case -ETIMEDOUT:
                return true;
        default:
                return false;
        }
}

static inline bool nfs_error_is_fatal_on_server(int err)
{
        switch (err) {
        case 0:
        case -ERESTARTSYS:
        case -EINTR:
        case -ENOMEM:
                return false;
        }
        return nfs_error_is_fatal(err);
}

/*
 * Select between a default port value and a user-specified port value.
 * If a zero value is set, then autobind will be used.
 */
static inline void nfs_set_port(struct sockaddr_storage *sap, int *port,
                                const unsigned short default_port)
{
        if (*port == NFS_UNSPEC_PORT)
                *port = default_port;

        rpc_set_port((struct sockaddr *)sap, *port);
}

struct nfs_direct_req {
        struct kref             kref;           /* release manager */

        /* I/O parameters */
        struct nfs_open_context *ctx;           /* file open context info */
        struct nfs_lock_context *l_ctx;         /* Lock context info */
        struct kiocb *          iocb;           /* controlling i/o request */
        struct inode *          inode;          /* target file of i/o */

        /* completion state */
        atomic_t                io_count;       /* i/os we're waiting for */
        spinlock_t              lock;           /* protect completion state */

        loff_t                  io_start;       /* Start offset for I/O */
        ssize_t                 count,          /* bytes actually processed */
                                max_count,      /* max expected count */
                                error;          /* any reported error */
        struct completion       completion;     /* wait for i/o completion */

        /* commit state */
        struct nfs_mds_commit_info mds_cinfo;   /* Storage for cinfo */
        struct pnfs_ds_commit_info ds_cinfo;    /* Storage for cinfo */
        struct work_struct      work;
        int                     flags;
        /* for write */
#define NFS_ODIRECT_DO_COMMIT           (1)     /* an unstable reply was received */
#define NFS_ODIRECT_RESCHED_WRITES      (2)     /* write verification failed */
        /* for read */
#define NFS_ODIRECT_SHOULD_DIRTY        (3)     /* dirty user-space page after read */
#define NFS_ODIRECT_DONE                INT_MAX /* write verification failed */
};