1f7b422b1SDavid Howells /* 2f7b422b1SDavid Howells * NFS internal definitions 3f7b422b1SDavid Howells */ 4f7b422b1SDavid Howells 5eedc020eSAndy Adamson #include "nfs4_fs.h" 6f7b422b1SDavid Howells #include <linux/mount.h> 7f9c3a380SEric Paris #include <linux/security.h> 8f7b422b1SDavid Howells 908734048SDavid Howells #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS) 1008734048SDavid Howells 1154ceac45SDavid Howells struct nfs_string; 1254ceac45SDavid Howells 1354ceac45SDavid Howells /* Maximum number of readahead requests 1454ceac45SDavid Howells * FIXME: this should really be a sysctl so that users may tune it to suit 1554ceac45SDavid Howells * their needs. People that do NFS over a slow network, might for 1654ceac45SDavid Howells * instance want to reduce it to something closer to 1 for improved 1754ceac45SDavid Howells * interactive response. 1854ceac45SDavid Howells */ 1954ceac45SDavid Howells #define NFS_MAX_READAHEAD (RPC_DEF_SLOT_TABLE - 1) 2054ceac45SDavid Howells 21eedc020eSAndy Adamson /* 22eedc020eSAndy Adamson * Determine if sessions are in use. 23eedc020eSAndy Adamson */ 24eedc020eSAndy Adamson static inline int nfs4_has_session(const struct nfs_client *clp) 25eedc020eSAndy Adamson { 26eedc020eSAndy Adamson #ifdef CONFIG_NFS_V4_1 27eedc020eSAndy Adamson if (clp->cl_session) 28eedc020eSAndy Adamson return 1; 29eedc020eSAndy Adamson #endif /* CONFIG_NFS_V4_1 */ 30eedc020eSAndy Adamson return 0; 31eedc020eSAndy Adamson } 32eedc020eSAndy Adamson 33f7b422b1SDavid Howells struct nfs_clone_mount { 34f7b422b1SDavid Howells const struct super_block *sb; 35f7b422b1SDavid Howells const struct dentry *dentry; 36f7b422b1SDavid Howells struct nfs_fh *fh; 37f7b422b1SDavid Howells struct nfs_fattr *fattr; 38f7b422b1SDavid Howells char *hostname; 39f7b422b1SDavid Howells char *mnt_path; 406677d095SChuck Lever struct sockaddr *addr; 416677d095SChuck Lever size_t addrlen; 42f7b422b1SDavid Howells rpc_authflavor_t authflavor; 43f7b422b1SDavid Howells }; 44f7b422b1SDavid Howells 456b18eaa0S\"Talpey, Thomas\ /* 46a14017dbSChuck Lever * Note: RFC 1813 doesn't limit the number of auth flavors that 47a14017dbSChuck Lever * a server can return, so make something up. 48a14017dbSChuck Lever */ 49a14017dbSChuck Lever #define NFS_MAX_SECFLAVORS (12) 50a14017dbSChuck Lever 51a14017dbSChuck Lever /* 524cfd74fcSChuck Lever * Value used if the user did not specify a port value. 534cfd74fcSChuck Lever */ 544cfd74fcSChuck Lever #define NFS_UNSPEC_PORT (-1) 554cfd74fcSChuck Lever 564cfd74fcSChuck Lever /* 576b18eaa0S\"Talpey, Thomas\ * In-kernel mount arguments 586b18eaa0S\"Talpey, Thomas\ */ 596b18eaa0S\"Talpey, Thomas\ struct nfs_parsed_mount_data { 606b18eaa0S\"Talpey, Thomas\ int flags; 616b18eaa0S\"Talpey, Thomas\ int rsize, wsize; 626b18eaa0S\"Talpey, Thomas\ int timeo, retrans; 636b18eaa0S\"Talpey, Thomas\ int acregmin, acregmax, 646b18eaa0S\"Talpey, Thomas\ acdirmin, acdirmax; 656b18eaa0S\"Talpey, Thomas\ int namlen; 66b797cac7SDavid Howells unsigned int options; 676b18eaa0S\"Talpey, Thomas\ unsigned int bsize; 686b18eaa0S\"Talpey, Thomas\ unsigned int auth_flavor_len; 696b18eaa0S\"Talpey, Thomas\ rpc_authflavor_t auth_flavors[1]; 706b18eaa0S\"Talpey, Thomas\ char *client_address; 71764302ccSChuck Lever unsigned int version; 723fd5be9eSMike Sager unsigned int minorversion; 7308734048SDavid Howells char *fscache_uniq; 746b18eaa0S\"Talpey, Thomas\ 756b18eaa0S\"Talpey, Thomas\ struct { 764c568017SChuck Lever struct sockaddr_storage address; 774c568017SChuck Lever size_t addrlen; 786b18eaa0S\"Talpey, Thomas\ char *hostname; 7978fa701fSChuck Lever u32 version; 804cfd74fcSChuck Lever int port; 8178fa701fSChuck Lever unsigned short protocol; 826b18eaa0S\"Talpey, Thomas\ } mount_server; 836b18eaa0S\"Talpey, Thomas\ 846b18eaa0S\"Talpey, Thomas\ struct { 854c568017SChuck Lever struct sockaddr_storage address; 864c568017SChuck Lever size_t addrlen; 876b18eaa0S\"Talpey, Thomas\ char *hostname; 886b18eaa0S\"Talpey, Thomas\ char *export_path; 894cfd74fcSChuck Lever int port; 9078fa701fSChuck Lever unsigned short protocol; 916b18eaa0S\"Talpey, Thomas\ } nfs_server; 92f9c3a380SEric Paris 93f9c3a380SEric Paris struct security_mnt_opts lsm_opts; 946b18eaa0S\"Talpey, Thomas\ }; 956b18eaa0S\"Talpey, Thomas\ 96146ec944SChuck Lever /* mount_clnt.c */ 97c5d120f8SChuck Lever struct nfs_mount_request { 98c5d120f8SChuck Lever struct sockaddr *sap; 99c5d120f8SChuck Lever size_t salen; 100c5d120f8SChuck Lever char *hostname; 101c5d120f8SChuck Lever char *dirpath; 102c5d120f8SChuck Lever u32 version; 103c5d120f8SChuck Lever unsigned short protocol; 104c5d120f8SChuck Lever struct nfs_fh *fh; 10550a737f8SChuck Lever int noresvport; 1068e02f6b9SChuck Lever unsigned int *auth_flav_len; 1078e02f6b9SChuck Lever rpc_authflavor_t *auth_flavs; 108c5d120f8SChuck Lever }; 109c5d120f8SChuck Lever 110c5d120f8SChuck Lever extern int nfs_mount(struct nfs_mount_request *info); 1110b524123SChuck Lever extern void nfs_umount(const struct nfs_mount_request *info); 112146ec944SChuck Lever 11324c8dbbbSDavid Howells /* client.c */ 11454ceac45SDavid Howells extern struct rpc_program nfs_program; 11554ceac45SDavid Howells 11624c8dbbbSDavid Howells extern void nfs_put_client(struct nfs_client *); 117ff052645SChuck Lever extern struct nfs_client *nfs_find_client(const struct sockaddr *, u32); 1183fbd67adSTrond Myklebust extern struct nfs_client *nfs_find_client_next(struct nfs_client *); 1192283f8d6S\"Talpey, Thomas\ extern struct nfs_server *nfs_create_server( 1202283f8d6S\"Talpey, Thomas\ const struct nfs_parsed_mount_data *, 12154ceac45SDavid Howells struct nfs_fh *); 12291ea40b9S\"Talpey, Thomas\ extern struct nfs_server *nfs4_create_server( 12391ea40b9S\"Talpey, Thomas\ const struct nfs_parsed_mount_data *, 12454ceac45SDavid Howells struct nfs_fh *); 12554ceac45SDavid Howells extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *, 12654ceac45SDavid Howells struct nfs_fh *); 12754ceac45SDavid Howells extern void nfs_free_server(struct nfs_server *server); 12854ceac45SDavid Howells extern struct nfs_server *nfs_clone_server(struct nfs_server *, 12954ceac45SDavid Howells struct nfs_fh *, 13054ceac45SDavid Howells struct nfs_fattr *); 13176db6d95SAndy Adamson extern void nfs_mark_client_ready(struct nfs_client *clp, int state); 132008f55d0SBenny Halevy extern int nfs4_check_client_ready(struct nfs_client *clp); 1336aaca566SDavid Howells #ifdef CONFIG_PROC_FS 1346aaca566SDavid Howells extern int __init nfs_fs_proc_init(void); 1356aaca566SDavid Howells extern void nfs_fs_proc_exit(void); 1366aaca566SDavid Howells #else 1376aaca566SDavid Howells static inline int nfs_fs_proc_init(void) 1386aaca566SDavid Howells { 1396aaca566SDavid Howells return 0; 1406aaca566SDavid Howells } 1416aaca566SDavid Howells static inline void nfs_fs_proc_exit(void) 1426aaca566SDavid Howells { 1436aaca566SDavid Howells } 1446aaca566SDavid Howells #endif 14524c8dbbbSDavid Howells 1467d4e2747SDavid Howells /* nfs4namespace.c */ 147f7b422b1SDavid Howells #ifdef CONFIG_NFS_V4 148f7b422b1SDavid Howells extern struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry); 149f7b422b1SDavid Howells #else 150f7b422b1SDavid Howells static inline 151f7b422b1SDavid Howells struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry) 152f7b422b1SDavid Howells { 153f7b422b1SDavid Howells return ERR_PTR(-ENOENT); 154f7b422b1SDavid Howells } 155f7b422b1SDavid Howells #endif 156f7b422b1SDavid Howells 157f7b422b1SDavid Howells /* callback_xdr.c */ 158f7b422b1SDavid Howells extern struct svc_version nfs4_callback_version1; 159f7b422b1SDavid Howells 160f7b422b1SDavid Howells /* pagelist.c */ 161f7b422b1SDavid Howells extern int __init nfs_init_nfspagecache(void); 162266bee88SDavid Brownell extern void nfs_destroy_nfspagecache(void); 163f7b422b1SDavid Howells extern int __init nfs_init_readpagecache(void); 164266bee88SDavid Brownell extern void nfs_destroy_readpagecache(void); 165f7b422b1SDavid Howells extern int __init nfs_init_writepagecache(void); 166266bee88SDavid Brownell extern void nfs_destroy_writepagecache(void); 167f7b422b1SDavid Howells 168f7b422b1SDavid Howells extern int __init nfs_init_directcache(void); 169266bee88SDavid Brownell extern void nfs_destroy_directcache(void); 170f7b422b1SDavid Howells 171f7b422b1SDavid Howells /* nfs2xdr.c */ 1727d4e2747SDavid Howells extern int nfs_stat_to_errno(int); 173f7b422b1SDavid Howells extern struct rpc_procinfo nfs_procedures[]; 1740dbb4c67SAl Viro extern __be32 * nfs_decode_dirent(__be32 *, struct nfs_entry *, int); 175f7b422b1SDavid Howells 176f7b422b1SDavid Howells /* nfs3xdr.c */ 177f7b422b1SDavid Howells extern struct rpc_procinfo nfs3_procedures[]; 1780dbb4c67SAl Viro extern __be32 *nfs3_decode_dirent(__be32 *, struct nfs_entry *, int); 179f7b422b1SDavid Howells 180eedc020eSAndy Adamson /* nfs4proc.c */ 181eedc020eSAndy Adamson static inline void nfs4_restart_rpc(struct rpc_task *task, 182eedc020eSAndy Adamson const struct nfs_client *clp) 183eedc020eSAndy Adamson { 184eedc020eSAndy Adamson #ifdef CONFIG_NFS_V4_1 185eedc020eSAndy Adamson if (nfs4_has_session(clp) && 186eedc020eSAndy Adamson test_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state)) { 187eedc020eSAndy Adamson rpc_restart_call_prepare(task); 188eedc020eSAndy Adamson return; 189eedc020eSAndy Adamson } 190eedc020eSAndy Adamson #endif /* CONFIG_NFS_V4_1 */ 191eedc020eSAndy Adamson rpc_restart_call(task); 192eedc020eSAndy Adamson } 193eedc020eSAndy Adamson 194f7b422b1SDavid Howells /* nfs4xdr.c */ 1957d4e2747SDavid Howells #ifdef CONFIG_NFS_V4 1960dbb4c67SAl Viro extern __be32 *nfs4_decode_dirent(__be32 *p, struct nfs_entry *entry, int plus); 1977d4e2747SDavid Howells #endif 198f7b422b1SDavid Howells 199f7b422b1SDavid Howells /* nfs4proc.c */ 200d75d5414SAndrew Morton #ifdef CONFIG_NFS_V4 201f7b422b1SDavid Howells extern struct rpc_procinfo nfs4_procedures[]; 202d75d5414SAndrew Morton #endif 203f7b422b1SDavid Howells 2047fe5c398STrond Myklebust /* proc.c */ 2057fe5c398STrond Myklebust void nfs_close_context(struct nfs_open_context *ctx, int is_sync); 2067fe5c398STrond Myklebust 207979df72eSTrond Myklebust /* dir.c */ 208979df72eSTrond Myklebust extern int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask); 209979df72eSTrond Myklebust 210f7b422b1SDavid Howells /* inode.c */ 2115746006fSTrond Myklebust extern struct workqueue_struct *nfsiod_workqueue; 212f7b422b1SDavid Howells extern struct inode *nfs_alloc_inode(struct super_block *sb); 213f7b422b1SDavid Howells extern void nfs_destroy_inode(struct inode *); 214f7b422b1SDavid Howells extern int nfs_write_inode(struct inode *,int); 215f7b422b1SDavid Howells extern void nfs_clear_inode(struct inode *); 216f7b422b1SDavid Howells #ifdef CONFIG_NFS_V4 217f7b422b1SDavid Howells extern void nfs4_clear_inode(struct inode *); 218f7b422b1SDavid Howells #endif 219f41f7418STrond Myklebust void nfs_zap_acl_cache(struct inode *inode); 22072cb77f4STrond Myklebust extern int nfs_wait_bit_killable(void *word); 221f7b422b1SDavid Howells 222f7b422b1SDavid Howells /* super.c */ 22354ceac45SDavid Howells extern struct file_system_type nfs_xdev_fs_type; 224f7b422b1SDavid Howells #ifdef CONFIG_NFS_V4 22554ceac45SDavid Howells extern struct file_system_type nfs4_xdev_fs_type; 22654ceac45SDavid Howells extern struct file_system_type nfs4_referral_fs_type; 227f7b422b1SDavid Howells #endif 2284ebd9ab3SDominik Hackl 229f7b422b1SDavid Howells extern struct rpc_stat nfs_rpcstat; 2304ebd9ab3SDominik Hackl 231f7b422b1SDavid Howells extern int __init register_nfs_fs(void); 232f7b422b1SDavid Howells extern void __exit unregister_nfs_fs(void); 2331daef0a8STrond Myklebust extern void nfs_sb_active(struct super_block *sb); 2341daef0a8STrond Myklebust extern void nfs_sb_deactive(struct super_block *sb); 235f7b422b1SDavid Howells 236f7b422b1SDavid Howells /* namespace.c */ 23754ceac45SDavid Howells extern char *nfs_path(const char *base, 23854ceac45SDavid Howells const struct dentry *droot, 23954ceac45SDavid Howells const struct dentry *dentry, 240f7b422b1SDavid Howells char *buffer, ssize_t buflen); 241f7b422b1SDavid Howells 24254ceac45SDavid Howells /* getroot.c */ 24354ceac45SDavid Howells extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *); 2447d4e2747SDavid Howells #ifdef CONFIG_NFS_V4 24554ceac45SDavid Howells extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *); 24654ceac45SDavid Howells 24754ceac45SDavid Howells extern int nfs4_path_walk(struct nfs_server *server, 24854ceac45SDavid Howells struct nfs_fh *mntfh, 24954ceac45SDavid Howells const char *path); 2507d4e2747SDavid Howells #endif 251f7b422b1SDavid Howells 252f11c88afSAndy Adamson /* read.c */ 253f11c88afSAndy Adamson extern void nfs_read_prepare(struct rpc_task *task, void *calldata); 254f11c88afSAndy Adamson 255def6ed7eSAndy Adamson /* write.c */ 256def6ed7eSAndy Adamson extern void nfs_write_prepare(struct rpc_task *task, void *calldata); 257074cc1deSTrond Myklebust #ifdef CONFIG_MIGRATION 258074cc1deSTrond Myklebust extern int nfs_migrate_page(struct address_space *, 259074cc1deSTrond Myklebust struct page *, struct page *); 260074cc1deSTrond Myklebust #else 261074cc1deSTrond Myklebust #define nfs_migrate_page NULL 262074cc1deSTrond Myklebust #endif 263def6ed7eSAndy Adamson 264cccef3b9SAndy Adamson /* nfs4proc.c */ 265cccef3b9SAndy Adamson extern int _nfs4_call_sync(struct nfs_server *server, 266cccef3b9SAndy Adamson struct rpc_message *msg, 267cccef3b9SAndy Adamson struct nfs4_sequence_args *args, 268cccef3b9SAndy Adamson struct nfs4_sequence_res *res, 269cccef3b9SAndy Adamson int cache_reply); 270cccef3b9SAndy Adamson extern int _nfs4_call_sync_session(struct nfs_server *server, 271cccef3b9SAndy Adamson struct rpc_message *msg, 272cccef3b9SAndy Adamson struct nfs4_sequence_args *args, 273cccef3b9SAndy Adamson struct nfs4_sequence_res *res, 274cccef3b9SAndy Adamson int cache_reply); 275cccef3b9SAndy Adamson 27613615871SAndy Adamson #ifdef CONFIG_NFS_V4_1 27713615871SAndy Adamson extern void nfs41_sequence_free_slot(const struct nfs_client *, 27813615871SAndy Adamson struct nfs4_sequence_res *res); 27913615871SAndy Adamson #endif /* CONFIG_NFS_V4_1 */ 28013615871SAndy Adamson 28113615871SAndy Adamson static inline void nfs4_sequence_free_slot(const struct nfs_client *clp, 28213615871SAndy Adamson struct nfs4_sequence_res *res) 28313615871SAndy Adamson { 28413615871SAndy Adamson #ifdef CONFIG_NFS_V4_1 28513615871SAndy Adamson if (nfs4_has_session(clp)) 28613615871SAndy Adamson nfs41_sequence_free_slot(clp, res); 28713615871SAndy Adamson #endif /* CONFIG_NFS_V4_1 */ 28813615871SAndy Adamson } 28913615871SAndy Adamson 290557134a3SAndy Adamson /* 291f7b422b1SDavid Howells * Determine the device name as a string 292f7b422b1SDavid Howells */ 293f7b422b1SDavid Howells static inline char *nfs_devname(const struct vfsmount *mnt_parent, 294f7b422b1SDavid Howells const struct dentry *dentry, 295f7b422b1SDavid Howells char *buffer, ssize_t buflen) 296f7b422b1SDavid Howells { 29754ceac45SDavid Howells return nfs_path(mnt_parent->mnt_devname, mnt_parent->mnt_root, 29854ceac45SDavid Howells dentry, buffer, buflen); 299f7b422b1SDavid Howells } 300f7b422b1SDavid Howells 301f7b422b1SDavid Howells /* 302f7b422b1SDavid Howells * Determine the actual block size (and log2 thereof) 303f7b422b1SDavid Howells */ 304f7b422b1SDavid Howells static inline 305f7b422b1SDavid Howells unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp) 306f7b422b1SDavid Howells { 307f7b422b1SDavid Howells /* make sure blocksize is a power of two */ 308f7b422b1SDavid Howells if ((bsize & (bsize - 1)) || nrbitsp) { 309f7b422b1SDavid Howells unsigned char nrbits; 310f7b422b1SDavid Howells 311f7b422b1SDavid Howells for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--) 312f7b422b1SDavid Howells ; 313f7b422b1SDavid Howells bsize = 1 << nrbits; 314f7b422b1SDavid Howells if (nrbitsp) 315f7b422b1SDavid Howells *nrbitsp = nrbits; 316f7b422b1SDavid Howells } 317f7b422b1SDavid Howells 318f7b422b1SDavid Howells return bsize; 319f7b422b1SDavid Howells } 320f7b422b1SDavid Howells 321f7b422b1SDavid Howells /* 322f7b422b1SDavid Howells * Calculate the number of 512byte blocks used. 323f7b422b1SDavid Howells */ 3249eaa67c6SChuck Lever static inline blkcnt_t nfs_calc_block_size(u64 tsize) 325f7b422b1SDavid Howells { 3269eaa67c6SChuck Lever blkcnt_t used = (tsize + 511) >> 9; 327f7b422b1SDavid Howells return (used > ULONG_MAX) ? ULONG_MAX : used; 328f7b422b1SDavid Howells } 329f7b422b1SDavid Howells 330f7b422b1SDavid Howells /* 331f7b422b1SDavid Howells * Compute and set NFS server blocksize 332f7b422b1SDavid Howells */ 333f7b422b1SDavid Howells static inline 334f7b422b1SDavid Howells unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp) 335f7b422b1SDavid Howells { 336f7b422b1SDavid Howells if (bsize < NFS_MIN_FILE_IO_SIZE) 337f7b422b1SDavid Howells bsize = NFS_DEF_FILE_IO_SIZE; 338f7b422b1SDavid Howells else if (bsize >= NFS_MAX_FILE_IO_SIZE) 339f7b422b1SDavid Howells bsize = NFS_MAX_FILE_IO_SIZE; 340f7b422b1SDavid Howells 341f7b422b1SDavid Howells return nfs_block_bits(bsize, nrbitsp); 342f7b422b1SDavid Howells } 343f7b422b1SDavid Howells 344f7b422b1SDavid Howells /* 345f7b422b1SDavid Howells * Determine the maximum file size for a superblock 346f7b422b1SDavid Howells */ 347f7b422b1SDavid Howells static inline 348f7b422b1SDavid Howells void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize) 349f7b422b1SDavid Howells { 350f7b422b1SDavid Howells sb->s_maxbytes = (loff_t)maxfilesize; 351f7b422b1SDavid Howells if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0) 352f7b422b1SDavid Howells sb->s_maxbytes = MAX_LFS_FILESIZE; 353f7b422b1SDavid Howells } 35449a70f27STrond Myklebust 35549a70f27STrond Myklebust /* 35649a70f27STrond Myklebust * Determine the number of bytes of data the page contains 35749a70f27STrond Myklebust */ 35849a70f27STrond Myklebust static inline 35949a70f27STrond Myklebust unsigned int nfs_page_length(struct page *page) 36049a70f27STrond Myklebust { 36149a70f27STrond Myklebust loff_t i_size = i_size_read(page->mapping->host); 36249a70f27STrond Myklebust 36349a70f27STrond Myklebust if (i_size > 0) { 36449a70f27STrond Myklebust pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; 36549a70f27STrond Myklebust if (page->index < end_index) 36649a70f27STrond Myklebust return PAGE_CACHE_SIZE; 36749a70f27STrond Myklebust if (page->index == end_index) 36849a70f27STrond Myklebust return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1; 36949a70f27STrond Myklebust } 37049a70f27STrond Myklebust return 0; 37149a70f27STrond Myklebust } 3728d5658c9STrond Myklebust 3738d5658c9STrond Myklebust /* 3748d5658c9STrond Myklebust * Determine the number of pages in an array of length 'len' and 3758d5658c9STrond Myklebust * with a base offset of 'base' 3768d5658c9STrond Myklebust */ 3778d5658c9STrond Myklebust static inline 3788d5658c9STrond Myklebust unsigned int nfs_page_array_len(unsigned int base, size_t len) 3798d5658c9STrond Myklebust { 3808d5658c9STrond Myklebust return ((unsigned long)len + (unsigned long)base + 3818d5658c9STrond Myklebust PAGE_SIZE - 1) >> PAGE_SHIFT; 3828d5658c9STrond Myklebust } 383