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