fs/nfs/internal.h

   1 /*
   2  * NFS internal definitions
   3  */
   4
   5 #include <linux/mount.h>
   6
   7 struct nfs_string;
   8
   9 /* Maximum number of readahead requests
  10  * FIXME: this should really be a sysctl so that users may tune it to suit
  11  *        their needs. People that do NFS over a slow network, might for
  12  *        instance want to reduce it to something closer to 1 for improved
  13  *        interactive response.
  14  */
  15 #define NFS_MAX_READAHEAD       (RPC_DEF_SLOT_TABLE - 1)
  16
  17 struct nfs_clone_mount {
  18         const struct super_block *sb;
  19         const struct dentry *dentry;
  20         struct nfs_fh *fh;
  21         struct nfs_fattr *fattr;
  22         char *hostname;
  23         char *mnt_path;
  24         struct sockaddr *addr;
  25         size_t addrlen;
  26         rpc_authflavor_t authflavor;
  27 };
  28
  29 /*
  30  * In-kernel mount arguments
  31  */
  32 struct nfs_parsed_mount_data {
  33         int                     flags;
  34         int                     rsize, wsize;
  35         int                     timeo, retrans;
  36         int                     acregmin, acregmax,
  37                                 acdirmin, acdirmax;
  38         int                     namlen;
  39         unsigned int            bsize;
  40         unsigned int            auth_flavor_len;
  41         rpc_authflavor_t        auth_flavors[1];
  42         char                    *client_address;
  43
  44         struct {
  45                 struct sockaddr_storage address;
  46                 size_t                  addrlen;
  47                 char                    *hostname;
  48                 unsigned int            version;
  49                 unsigned short          port;
  50                 int                     protocol;
  51         } mount_server;
  52
  53         struct {
  54                 struct sockaddr_storage address;
  55                 size_t                  addrlen;
  56                 char                    *hostname;
  57                 char                    *export_path;
  58                 int                     protocol;
  59         } nfs_server;
  60 };
  61
  62 /* client.c */
  63 extern struct rpc_program nfs_program;
  64
  65 extern void nfs_put_client(struct nfs_client *);
  66 extern struct nfs_client *nfs_find_client(const struct sockaddr *, u32);
  67 extern struct nfs_client *nfs_find_client_next(struct nfs_client *);
  68 extern struct nfs_server *nfs_create_server(
  69                                         const struct nfs_parsed_mount_data *,
  70                                         struct nfs_fh *);
  71 extern struct nfs_server *nfs4_create_server(
  72                                         const struct nfs_parsed_mount_data *,
  73                                         struct nfs_fh *);
  74 extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
  75                                                       struct nfs_fh *);
  76 extern void nfs_free_server(struct nfs_server *server);
  77 extern struct nfs_server *nfs_clone_server(struct nfs_server *,
  78                                            struct nfs_fh *,
  79                                            struct nfs_fattr *);
  80 #ifdef CONFIG_PROC_FS
  81 extern int __init nfs_fs_proc_init(void);
  82 extern void nfs_fs_proc_exit(void);
  83 #else
  84 static inline int nfs_fs_proc_init(void)
  85 {
  86         return 0;
  87 }
  88 static inline void nfs_fs_proc_exit(void)
  89 {
  90 }
  91 #endif
  92
  93 /* nfs4namespace.c */
  94 #ifdef CONFIG_NFS_V4
  95 extern struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry);
  96 #else
  97 static inline
  98 struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry)
  99 {
 100         return ERR_PTR(-ENOENT);
 101 }
 102 #endif
 103
 104 /* callback_xdr.c */
 105 extern struct svc_version nfs4_callback_version1;
 106
 107 /* pagelist.c */
 108 extern int __init nfs_init_nfspagecache(void);
 109 extern void nfs_destroy_nfspagecache(void);
 110 extern int __init nfs_init_readpagecache(void);
 111 extern void nfs_destroy_readpagecache(void);
 112 extern int __init nfs_init_writepagecache(void);
 113 extern void nfs_destroy_writepagecache(void);
 114
 115 #ifdef CONFIG_NFS_DIRECTIO
 116 extern int __init nfs_init_directcache(void);
 117 extern void nfs_destroy_directcache(void);
 118 #else
 119 #define nfs_init_directcache() (0)
 120 #define nfs_destroy_directcache() do {} while(0)
 121 #endif
 122
 123 /* nfs2xdr.c */
 124 extern int nfs_stat_to_errno(int);
 125 extern struct rpc_procinfo nfs_procedures[];
 126 extern __be32 * nfs_decode_dirent(__be32 *, struct nfs_entry *, int);
 127
 128 /* nfs3xdr.c */
 129 extern struct rpc_procinfo nfs3_procedures[];
 130 extern __be32 *nfs3_decode_dirent(__be32 *, struct nfs_entry *, int);
 131
 132 /* nfs4xdr.c */
 133 #ifdef CONFIG_NFS_V4
 134 extern __be32 *nfs4_decode_dirent(__be32 *p, struct nfs_entry *entry, int plus);
 135 #endif
 136
 137 /* nfs4proc.c */
 138 #ifdef CONFIG_NFS_V4
 139 extern struct rpc_procinfo nfs4_procedures[];
 140 #endif
 141
 142 /* dir.c */
 143 extern int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask);
 144
 145 /* inode.c */
 146 extern struct inode *nfs_alloc_inode(struct super_block *sb);
 147 extern void nfs_destroy_inode(struct inode *);
 148 extern int nfs_write_inode(struct inode *,int);
 149 extern void nfs_clear_inode(struct inode *);
 150 #ifdef CONFIG_NFS_V4
 151 extern void nfs4_clear_inode(struct inode *);
 152 #endif
 153
 154 /* super.c */
 155 extern struct file_system_type nfs_xdev_fs_type;
 156 #ifdef CONFIG_NFS_V4
 157 extern struct file_system_type nfs4_xdev_fs_type;
 158 extern struct file_system_type nfs4_referral_fs_type;
 159 #endif
 160
 161 extern struct rpc_stat nfs_rpcstat;
 162
 163 extern int __init register_nfs_fs(void);
 164 extern void __exit unregister_nfs_fs(void);
 165 extern void nfs_sb_active(struct nfs_server *server);
 166 extern void nfs_sb_deactive(struct nfs_server *server);
 167
 168 /* namespace.c */
 169 extern char *nfs_path(const char *base,
 170                       const struct dentry *droot,
 171                       const struct dentry *dentry,
 172                       char *buffer, ssize_t buflen);
 173
 174 /* getroot.c */
 175 extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *);
 176 #ifdef CONFIG_NFS_V4
 177 extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *);
 178
 179 extern int nfs4_path_walk(struct nfs_server *server,
 180                           struct nfs_fh *mntfh,
 181                           const char *path);
 182 #endif
 183
 184 /*
 185  * Determine the device name as a string
 186  */
 187 static inline char *nfs_devname(const struct vfsmount *mnt_parent,
 188                                 const struct dentry *dentry,
 189                                 char *buffer, ssize_t buflen)
 190 {
 191         return nfs_path(mnt_parent->mnt_devname, mnt_parent->mnt_root,
 192                         dentry, buffer, buflen);
 193 }
 194
 195 /*
 196  * Determine the actual block size (and log2 thereof)
 197  */
 198 static inline
 199 unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
 200 {
 201         /* make sure blocksize is a power of two */
 202         if ((bsize & (bsize - 1)) || nrbitsp) {
 203                 unsigned char   nrbits;
 204
 205                 for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
 206                         ;
 207                 bsize = 1 << nrbits;
 208                 if (nrbitsp)
 209                         *nrbitsp = nrbits;
 210         }
 211
 212         return bsize;
 213 }
 214
 215 /*
 216  * Calculate the number of 512byte blocks used.
 217  */
 218 static inline blkcnt_t nfs_calc_block_size(u64 tsize)
 219 {
 220         blkcnt_t used = (tsize + 511) >> 9;
 221         return (used > ULONG_MAX) ? ULONG_MAX : used;
 222 }
 223
 224 /*
 225  * Compute and set NFS server blocksize
 226  */
 227 static inline
 228 unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
 229 {
 230         if (bsize < NFS_MIN_FILE_IO_SIZE)
 231                 bsize = NFS_DEF_FILE_IO_SIZE;
 232         else if (bsize >= NFS_MAX_FILE_IO_SIZE)
 233                 bsize = NFS_MAX_FILE_IO_SIZE;
 234
 235         return nfs_block_bits(bsize, nrbitsp);
 236 }
 237
 238 /*
 239  * Determine the maximum file size for a superblock
 240  */
 241 static inline
 242 void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
 243 {
 244         sb->s_maxbytes = (loff_t)maxfilesize;
 245         if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0)
 246                 sb->s_maxbytes = MAX_LFS_FILESIZE;
 247 }
 248
 249 /*
 250  * Determine the number of bytes of data the page contains
 251  */
 252 static inline
 253 unsigned int nfs_page_length(struct page *page)
 254 {
 255         loff_t i_size = i_size_read(page->mapping->host);
 256
 257         if (i_size > 0) {
 258                 pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
 259                 if (page->index < end_index)
 260                         return PAGE_CACHE_SIZE;
 261                 if (page->index == end_index)
 262                         return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1;
 263         }
 264         return 0;
 265 }
 266
 267 /*
 268  * Determine the number of pages in an array of length 'len' and
 269  * with a base offset of 'base'
 270  */
 271 static inline
 272 unsigned int nfs_page_array_len(unsigned int base, size_t len)
 273 {
 274         return ((unsigned long)len + (unsigned long)base +
 275                 PAGE_SIZE - 1) >> PAGE_SHIFT;
 276 }
 277