internal.h

Go to the documentation of this file.

/*
 * NFS internal definitions
 */

#include "nfs4_fs.h"
#include <linux/mount.h>
#include <linux/security.h>

#define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)

struct nfs_string;

/* Maximum number of readahead requests
 * FIXME: this should really be a sysctl so that users may tune it to suit
 *        their needs. People that do NFS over a slow network, might for
 *        instance want to reduce it to something closer to 1 for improved
 *        interactive response.
 */
#define NFS_MAX_READAHEAD   (RPC_DEF_SLOT_TABLE - 1)

/*
 * Determine if sessions are in use.
 */
static inline int nfs4_has_session(const struct nfs_client *clp)
{
#ifdef CONFIG_NFS_V4_1
    if (clp->cl_session)
        return 1;
#endif /* CONFIG_NFS_V4_1 */
    return 0;
}

static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
{
#ifdef CONFIG_NFS_V4_1
    if (nfs4_has_session(clp))
        return (clp->cl_session->flags & SESSION4_PERSIST);
#endif /* CONFIG_NFS_V4_1 */
    return 0;
}

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;

    fattr->fileid = fattr->mounted_on_fileid;
    return 1;
}

struct nfs_clone_mount {
    const struct super_block *sb;
    const struct dentry *dentry;
    struct nfs_fh *fh;
    struct nfs_fattr *fattr;
    char *hostname;
    char *mnt_path;
    struct sockaddr *addr;
    size_t addrlen;
    rpc_authflavor_t authflavor;
};

/*
 * 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)

/*
 * Maximum number of pages that readdir can use for creating
 * a vmapped array of pages.
 */
#define NFS_MAX_READDIR_PAGES 8

struct nfs_client_initdata {
    unsigned long init_flags;
    const char *hostname;
    const struct sockaddr *addr;
    size_t addrlen;
    struct nfs_subversion *nfs_mod;
    int proto;
    u32 minorversion;
    struct net *net;
};

/*
 * In-kernel mount arguments
 */
struct nfs_parsed_mount_data {
    int         flags;
    unsigned int        rsize, wsize;
    unsigned int        timeo, retrans;
    unsigned int        acregmin, acregmax,
                acdirmin, acdirmax;
    unsigned int        namlen;
    unsigned int        options;
    unsigned int        bsize;
    unsigned int        auth_flavor_len;
    rpc_authflavor_t    auth_flavors[1];
    char            *client_address;
    unsigned int        version;
    unsigned int        minorversion;
    char            *fscache_uniq;
    bool            need_mount;

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

    struct {
        struct sockaddr_storage address;
        size_t          addrlen;
        char            *hostname;
        char            *export_path;
        int         port;
        unsigned short      protocol;
    } nfs_server;

    struct security_mnt_opts lsm_opts;
    struct net      *net;
};

/* mount_clnt.c */
struct nfs_mount_request {
    struct sockaddr     *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;
};

struct nfs_mount_info {
    void (*fill_super)(struct super_block *, struct nfs_mount_info *);
    int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
    struct nfs_parsed_mount_data *parsed;
    struct nfs_clone_mount *cloned;
    struct nfs_fh *mntfh;
};

extern int nfs_mount(struct nfs_mount_request *info);
extern void nfs_umount(const struct nfs_mount_request *info);

/* client.c */
extern const struct rpc_program nfs_program;
extern void nfs_clients_init(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 rpc_timeout *, rpc_authflavor_t);
struct nfs_client *nfs_get_client(const struct nfs_client_initdata *,
                  const struct rpc_timeout *, const char *,
                  rpc_authflavor_t);
int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *, struct nfs_fattr *);
void nfs_server_insert_lists(struct nfs_server *);
void nfs_init_timeout_values(struct rpc_timeout *, int, unsigned int, unsigned int);
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_cleanup_cb_ident_idr(struct net *);
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 *);
extern struct nfs_server *nfs_create_server(struct nfs_mount_info *,
                    struct nfs_subversion *);
extern struct nfs_server *nfs4_create_server(
                    struct nfs_mount_info *,
                    struct nfs_subversion *);
extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
                              struct nfs_fh *);
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 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_client* mds_clp,
                         const struct sockaddr *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);
#else
static inline int nfs_fs_proc_init(void)
{
    return 0;
}
static inline void nfs_fs_proc_exit(void)
{
}
#endif

#ifdef CONFIG_NFS_V4_1
int nfs_sockaddr_match_ipaddr(const struct sockaddr *, const struct sockaddr *);
#endif

/* nfs3client.c */
#if IS_ENABLED(CONFIG_NFS_V3)
struct nfs_server *nfs3_create_server(struct nfs_mount_info *, struct nfs_subversion *);
struct nfs_server *nfs3_clone_server(struct nfs_server *, struct nfs_fh *,
                     struct nfs_fattr *, rpc_authflavor_t);
#endif

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

struct nfs_pageio_descriptor;
/* 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 bool nfs_pgarray_set(struct nfs_page_array *p, unsigned int pagecount);
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);

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

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

/* nfs4xdr.c */
#if IS_ENABLED(CONFIG_NFS_V4)
extern int nfs4_decode_dirent(struct xdr_stream *,
                struct nfs_entry *, int);
#endif
#ifdef CONFIG_NFS_V4_1
extern const u32 nfs41_maxread_overhead;
extern const u32 nfs41_maxwrite_overhead;
#endif

/* nfs4proc.c */
#if IS_ENABLED(CONFIG_NFS_V4)
extern struct rpc_procinfo nfs4_procedures[];
#endif

extern int nfs4_init_ds_session(struct nfs_client *, unsigned long);

/* 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 rpc_timeout *timeparms,
               const char *ip_addr, rpc_authflavor_t authflavour);

/* dir.c */
extern int nfs_access_cache_shrinker(struct shrinker *shrink,
                    struct shrink_control *sc);
struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
int nfs_create(struct inode *, struct dentry *, umode_t, bool);
int nfs_mkdir(struct inode *, struct dentry *, umode_t);
int nfs_rmdir(struct inode *, struct dentry *);
int nfs_unlink(struct inode *, struct dentry *);
int nfs_symlink(struct inode *, struct dentry *, const char *);
int nfs_link(struct dentry *, struct inode *, struct dentry *);
int nfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);

/* file.c */
int nfs_file_fsync_commit(struct file *, loff_t, loff_t, int);
loff_t nfs_file_llseek(struct file *, loff_t, int);
int nfs_file_flush(struct file *, fl_owner_t);
ssize_t nfs_file_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *,
                 size_t, unsigned int);
int nfs_file_mmap(struct file *, struct vm_area_struct *);
ssize_t nfs_file_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
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 *);
ssize_t nfs_file_splice_write(struct pipe_inode_info *, struct file *, loff_t *,
                  size_t, unsigned int);
int nfs_check_flags(int);
int nfs_setlease(struct file *, long, struct file_lock **);

/* inode.c */
extern struct workqueue_struct *nfsiod_workqueue;
extern struct inode *nfs_alloc_inode(struct super_block *sb);
extern void nfs_destroy_inode(struct inode *);
extern int nfs_write_inode(struct inode *, struct writeback_control *);
extern void nfs_clear_inode(struct inode *);
extern void nfs_evict_inode(struct inode *);
void nfs_zap_acl_cache(struct inode *inode);
extern int nfs_wait_bit_killable(void *word);

/* super.c */
extern const struct super_operations nfs_sops;
extern struct file_system_type nfs_fs_type;
extern struct file_system_type nfs_xdev_fs_type;
#if IS_ENABLED(CONFIG_NFS_V4)
extern struct file_system_type nfs4_xdev_fs_type;
extern struct file_system_type nfs4_referral_fs_type;
#endif
struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *,
            struct nfs_subversion *);
void nfs_initialise_sb(struct super_block *);
int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
struct dentry *nfs_fs_mount_common(struct nfs_server *, int, const char *,
                   struct nfs_mount_info *, struct nfs_subversion *);
struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
        const char *, struct nfs_mount_info *);
void nfs_kill_super(struct super_block *);
void nfs_fill_super(struct super_block *, struct nfs_mount_info *);

extern struct rpc_stat nfs_rpcstat;

extern int __init register_nfs_fs(void);
extern void __exit unregister_nfs_fs(void);
extern void nfs_sb_active(struct super_block *sb);
extern void nfs_sb_deactive(struct super_block *sb);
extern void nfs_sb_deactive_async(struct super_block *sb);

/* 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);
struct vfsmount *nfs_submount(struct nfs_server *, struct dentry *,
                  struct nfs_fh *, struct nfs_fattr *);
struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *,
                 struct nfs_fattr *, rpc_authflavor_t);

/* getroot.c */
extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
                   const char *);
#if IS_ENABLED(CONFIG_NFS_V4)
extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *,
                    const char *);

extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh);
#endif

struct nfs_pgio_completion_ops;
/* read.c */
extern struct nfs_read_header *nfs_readhdr_alloc(void);
extern void nfs_readhdr_free(struct nfs_pgio_header *hdr);
extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
            struct inode *inode,
            const struct nfs_pgio_completion_ops *compl_ops);
extern int nfs_initiate_read(struct rpc_clnt *clnt,
                 struct nfs_read_data *data,
                 const struct rpc_call_ops *call_ops, int flags);
extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
extern int nfs_generic_pagein(struct nfs_pageio_descriptor *desc,
                  struct nfs_pgio_header *hdr);
extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
            struct inode *inode,
            const struct nfs_pgio_completion_ops *compl_ops);
extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
extern void nfs_readdata_release(struct nfs_read_data *rdata);

/* super.c */
void nfs_clone_super(struct super_block *, struct nfs_mount_info *);
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 *);
void nfs_put_super(struct super_block *);
int nfs_remount(struct super_block *sb, int *flags, char *raw_data);

/* write.c */
extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
            struct inode *inode, int ioflags,
            const struct nfs_pgio_completion_ops *compl_ops);
extern struct nfs_write_header *nfs_writehdr_alloc(void);
extern void nfs_writehdr_free(struct nfs_pgio_header *hdr);
extern int nfs_generic_flush(struct nfs_pageio_descriptor *desc,
                 struct nfs_pgio_header *hdr);
extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
            struct inode *inode, int ioflags,
            const struct nfs_pgio_completion_ops *compl_ops);
extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
extern void nfs_writedata_release(struct nfs_write_data *wdata);
extern void nfs_commit_free(struct nfs_commit_data *p);
extern int nfs_initiate_write(struct rpc_clnt *clnt,
                  struct nfs_write_data *data,
                  const struct rpc_call_ops *call_ops,
                  int how, int flags);
extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
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 rpc_call_ops *call_ops,
                   int how, int flags);
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);
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);
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);
void nfs_commitdata_release(struct nfs_commit_data *data);
void nfs_request_add_commit_list(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);

#ifdef CONFIG_MIGRATION
extern int nfs_migrate_page(struct address_space *,
        struct page *, struct page *, enum migrate_mode);
#else
#define nfs_migrate_page NULL
#endif

/* direct.c */
void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
                  struct nfs_direct_req *dreq);
static inline void nfs_inode_dio_wait(struct inode *inode)
{
    inode_dio_wait(inode);
}
extern ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq);

/* nfs4proc.c */
extern void __nfs4_read_done_cb(struct nfs_read_data *);
extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
                const struct rpc_timeout *timeparms,
                const char *ip_addr,
                rpc_authflavor_t authflavour);
extern int _nfs4_call_sync(struct rpc_clnt *clnt,
               struct nfs_server *server,
               struct rpc_message *msg,
               struct nfs4_sequence_args *args,
               struct nfs4_sequence_res *res,
               int cache_reply);
extern int _nfs4_call_sync_session(struct rpc_clnt *clnt,
                   struct nfs_server *server,
                   struct rpc_message *msg,
                   struct nfs4_sequence_args *args,
                   struct nfs4_sequence_res *res,
                   int cache_reply);
extern int nfs40_walk_client_list(struct nfs_client *clp,
                struct nfs_client **result,
                struct rpc_cred *cred);
extern int nfs41_walk_client_list(struct nfs_client *clp,
                struct nfs_client **result,
                struct rpc_cred *cred);

/*
 * 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 & (1 << nrbits)); nrbits--)
            ;
        bsize = 1 << 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);
}

/*
 * 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;
}

/*
 * Determine the number of bytes of data the page contains
 */
static inline
unsigned int nfs_page_length(struct page *page)
{
    loff_t i_size = i_size_read(page_file_mapping(page)->host);

    if (i_size > 0) {
        pgoff_t page_index = page_file_index(page);
        pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
        if (page_index < end_index)
            return PAGE_CACHE_SIZE;
        if (page_index == end_index)
            return ((i_size - 1) & ~PAGE_CACHE_MASK) + 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 timespec into a 64-bit change attribute
 *
 * This does approximately the same thing as timespec_to_ns(),
 * but for calculation efficiency, we multiply the seconds by
 * 1024*1024*1024.
 */
static inline
u64 nfs_timespec_to_change_attr(const struct timespec *ts)
{
    return ((u64)ts->tv_sec << 30) + ts->tv_nsec;
}