fs/nfs/internal.h

   1 /*
   2  * NFS internal definitions
   3  */
   4
   5 #include <linux/mount.h>
   6
   7 struct nfs_string;
   8 struct nfs_mount_data;
   9 struct nfs4_mount_data;
  10
  11 /* Maximum number of readahead requests
  12  * FIXME: this should really be a sysctl so that users may tune it to suit
  13  *        their needs. People that do NFS over a slow network, might for
  14  *        instance want to reduce it to something closer to 1 for improved
  15  *        interactive response.
  16  */
  17 #define NFS_MAX_READAHEAD       (RPC_DEF_SLOT_TABLE - 1)
  18
  19 struct nfs_clone_mount {
  20         const struct super_block *sb;
  21         const struct dentry *dentry;
  22         struct nfs_fh *fh;
  23         struct nfs_fattr *fattr;
  24         char *hostname;
  25         char *mnt_path;
  26         struct sockaddr_in *addr;
  27         rpc_authflavor_t authflavor;
  28 };
  29
  30 /* client.c */
  31 extern struct rpc_program nfs_program;
  32
  33 extern void nfs_put_client(struct nfs_client *);
  34 extern struct nfs_client *nfs_find_client(const struct sockaddr_in *, int);
  35 extern struct nfs_server *nfs_create_server(const struct nfs_mount_data *,
  36                                             struct nfs_fh *);
  37 extern struct nfs_server *nfs4_create_server(const struct nfs4_mount_data *,
  38                                              const char *,
  39                                              const struct sockaddr_in *,
  40                                              const char *,
  41                                              const char *,
  42                                              rpc_authflavor_t,
  43                                              struct nfs_fh *);
  44 extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
  45                                                       struct nfs_fh *);
  46 extern void nfs_free_server(struct nfs_server *server);
  47 extern struct nfs_server *nfs_clone_server(struct nfs_server *,
  48                                            struct nfs_fh *,
  49                                            struct nfs_fattr *);
  50 #ifdef CONFIG_PROC_FS
  51 extern int __init nfs_fs_proc_init(void);
  52 extern void nfs_fs_proc_exit(void);
  53 #else
  54 static inline int nfs_fs_proc_init(void)
  55 {
  56         return 0;
  57 }
  58 static inline void nfs_fs_proc_exit(void)
  59 {
  60 }
  61 #endif
  62
  63 /* nfs4namespace.c */
  64 #ifdef CONFIG_NFS_V4
  65 extern struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry);
  66 #else
  67 static inline
  68 struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry)
  69 {
  70         return ERR_PTR(-ENOENT);
  71 }
  72 #endif
  73
  74 /* callback_xdr.c */
  75 extern struct svc_version nfs4_callback_version1;
  76
  77 /* pagelist.c */
  78 extern int __init nfs_init_nfspagecache(void);
  79 extern void nfs_destroy_nfspagecache(void);
  80 extern int __init nfs_init_readpagecache(void);
  81 extern void nfs_destroy_readpagecache(void);
  82 extern int __init nfs_init_writepagecache(void);
  83 extern void nfs_destroy_writepagecache(void);
  84
  85 #ifdef CONFIG_NFS_DIRECTIO
  86 extern int __init nfs_init_directcache(void);
  87 extern void nfs_destroy_directcache(void);
  88 #else
  89 #define nfs_init_directcache() (0)
  90 #define nfs_destroy_directcache() do {} while(0)
  91 #endif
  92
  93 /* nfs2xdr.c */
  94 extern int nfs_stat_to_errno(int);
  95 extern struct rpc_procinfo nfs_procedures[];
  96 extern __be32 * nfs_decode_dirent(__be32 *, struct nfs_entry *, int);
  97
  98 /* nfs3xdr.c */
  99 extern struct rpc_procinfo nfs3_procedures[];
 100 extern __be32 *nfs3_decode_dirent(__be32 *, struct nfs_entry *, int);
 101
 102 /* nfs4xdr.c */
 103 #ifdef CONFIG_NFS_V4
 104 extern __be32 *nfs4_decode_dirent(__be32 *p, struct nfs_entry *entry, int plus);
 105 #endif
 106
 107 /* nfs4proc.c */
 108 #ifdef CONFIG_NFS_V4
 109 extern struct rpc_procinfo nfs4_procedures[];
 110 #endif
 111
 112 /* dir.c */
 113 extern int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask);
 114
 115 /* inode.c */
 116 extern struct inode *nfs_alloc_inode(struct super_block *sb);
 117 extern void nfs_destroy_inode(struct inode *);
 118 extern int nfs_write_inode(struct inode *,int);
 119 extern void nfs_clear_inode(struct inode *);
 120 #ifdef CONFIG_NFS_V4
 121 extern void nfs4_clear_inode(struct inode *);
 122 #endif
 123
 124 /* super.c */
 125 extern struct file_system_type nfs_xdev_fs_type;
 126 #ifdef CONFIG_NFS_V4
 127 extern struct file_system_type nfs4_xdev_fs_type;
 128 extern struct file_system_type nfs4_referral_fs_type;
 129 #endif
 130
 131 extern struct rpc_stat nfs_rpcstat;
 132
 133 extern int __init register_nfs_fs(void);
 134 extern void __exit unregister_nfs_fs(void);
 135
 136 /* namespace.c */
 137 extern char *nfs_path(const char *base,
 138                       const struct dentry *droot,
 139                       const struct dentry *dentry,
 140                       char *buffer, ssize_t buflen);
 141
 142 /* getroot.c */
 143 extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *);
 144 #ifdef CONFIG_NFS_V4
 145 extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *);
 146
 147 extern int nfs4_path_walk(struct nfs_server *server,
 148                           struct nfs_fh *mntfh,
 149                           const char *path);
 150 #endif
 151
 152 /*
 153  * Determine the device name as a string
 154  */
 155 static inline char *nfs_devname(const struct vfsmount *mnt_parent,
 156                                 const struct dentry *dentry,
 157                                 char *buffer, ssize_t buflen)
 158 {
 159         return nfs_path(mnt_parent->mnt_devname, mnt_parent->mnt_root,
 160                         dentry, buffer, buflen);
 161 }
 162
 163 /*
 164  * Determine the actual block size (and log2 thereof)
 165  */
 166 static inline
 167 unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
 168 {
 169         /* make sure blocksize is a power of two */
 170         if ((bsize & (bsize - 1)) || nrbitsp) {
 171                 unsigned char   nrbits;
 172
 173                 for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
 174                         ;
 175                 bsize = 1 << nrbits;
 176                 if (nrbitsp)
 177                         *nrbitsp = nrbits;
 178         }
 179
 180         return bsize;
 181 }
 182
 183 /*
 184  * Calculate the number of 512byte blocks used.
 185  */
 186 static inline blkcnt_t nfs_calc_block_size(u64 tsize)
 187 {
 188         blkcnt_t used = (tsize + 511) >> 9;
 189         return (used > ULONG_MAX) ? ULONG_MAX : used;
 190 }
 191
 192 /*
 193  * Compute and set NFS server blocksize
 194  */
 195 static inline
 196 unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
 197 {
 198         if (bsize < NFS_MIN_FILE_IO_SIZE)
 199                 bsize = NFS_DEF_FILE_IO_SIZE;
 200         else if (bsize >= NFS_MAX_FILE_IO_SIZE)
 201                 bsize = NFS_MAX_FILE_IO_SIZE;
 202
 203         return nfs_block_bits(bsize, nrbitsp);
 204 }
 205
 206 /*
 207  * Determine the maximum file size for a superblock
 208  */
 209 static inline
 210 void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
 211 {
 212         sb->s_maxbytes = (loff_t)maxfilesize;
 213         if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0)
 214                 sb->s_maxbytes = MAX_LFS_FILESIZE;
 215 }
 216
 217 /*
 218  * Determine the number of bytes of data the page contains
 219  */
 220 static inline
 221 unsigned int nfs_page_length(struct page *page)
 222 {
 223         loff_t i_size = i_size_read(page->mapping->host);
 224
 225         if (i_size > 0) {
 226                 pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
 227                 if (page->index < end_index)
 228                         return PAGE_CACHE_SIZE;
 229                 if (page->index == end_index)
 230                         return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1;
 231         }
 232         return 0;
 233 }
 234
 235 /*
 236  * Determine the number of pages in an array of length 'len' and
 237  * with a base offset of 'base'
 238  */
 239 static inline
 240 unsigned int nfs_page_array_len(unsigned int base, size_t len)
 241 {
 242         return ((unsigned long)len + (unsigned long)base +
 243                 PAGE_SIZE - 1) >> PAGE_SHIFT;
 244 }
 245