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[/] [or1k/] [trunk/] [uclinux/] [uClinux-2.0.x/] [fs/] [nfs/] [dir.c] - Rev 1765
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/* * linux/fs/nfs/dir.c * * Copyright (C) 1992 Rick Sladkey * * nfs directory handling functions * * 10 Apr 1996 Added silly rename for unlink --okir */ /* * Fixes: * Ion Badulescu <ionut@cs.columbia.edu> : FIFO's need special handling in NFSv2 */ #include <linux/sched.h> #include <linux/errno.h> #include <linux/stat.h> #include <linux/nfs_fs.h> #include <linux/fcntl.h> #include <linux/string.h> #include <linux/kernel.h> #include <linux/malloc.h> #include <linux/mm.h> #include <asm/segment.h> /* for fs functions */ static int nfs_dir_open(struct inode * inode, struct file * file); static int nfs_dir_read(struct inode *, struct file *, char *, int); static int nfs_readdir(struct inode *, struct file *, void *, filldir_t); static int nfs_lookup(struct inode *, const char *, int, struct inode **); static int nfs_create(struct inode *, const char *, int, int, struct inode **); static int nfs_mkdir(struct inode *, const char *, int, int); static int nfs_rmdir(struct inode *, const char *, int); static int nfs_unlink(struct inode *, const char *, int); static int nfs_symlink(struct inode *, const char *, int, const char *); static int nfs_link(struct inode *, struct inode *, const char *, int); static int nfs_mknod(struct inode *, const char *, int, int, int); static int nfs_rename(struct inode *, const char *, int, struct inode *, const char *, int, int); static struct file_operations nfs_dir_operations = { NULL, /* lseek - default */ nfs_dir_read, /* read - bad */ NULL, /* write - bad */ nfs_readdir, /* readdir */ NULL, /* select - default */ NULL, /* ioctl - default */ NULL, /* mmap */ nfs_dir_open, /* open - revalidate */ NULL, /* no special release code */ NULL /* fsync */ }; struct inode_operations nfs_dir_inode_operations = { &nfs_dir_operations, /* default directory file-ops */ nfs_create, /* create */ nfs_lookup, /* lookup */ nfs_link, /* link */ nfs_unlink, /* unlink */ nfs_symlink, /* symlink */ nfs_mkdir, /* mkdir */ nfs_rmdir, /* rmdir */ nfs_mknod, /* mknod */ nfs_rename, /* rename */ NULL, /* readlink */ NULL, /* follow_link */ NULL, /* readpage */ NULL, /* writepage */ NULL, /* bmap */ NULL, /* truncate */ NULL /* permission */ }; static inline void revalidate_dir(struct nfs_server * server, struct inode * dir) { struct nfs_fattr fattr; if (jiffies - NFS_READTIME(dir) < NFS_ATTRTIMEO(dir)) return; NFS_READTIME(dir) = jiffies; if (nfs_proc_getattr(server, NFS_FH(dir), &fattr) == 0) { nfs_refresh_inode(dir, &fattr); if (fattr.mtime.seconds == NFS_OLDMTIME(dir)) { if ((NFS_ATTRTIMEO(dir) <<= 1) > server->acdirmax) NFS_ATTRTIMEO(dir) = server->acdirmax; return; } NFS_OLDMTIME(dir) = fattr.mtime.seconds; } /* invalidate directory cache here when we _really_ start caching */ } static int nfs_dir_open(struct inode * dir, struct file * file) { revalidate_dir(NFS_SERVER(dir), dir); return 0; } static int nfs_dir_read(struct inode *inode, struct file *filp, char *buf, int count) { return -EISDIR; } static struct nfs_entry *c_entry = NULL; /* * We need to do caching of directory entries to prevent an * incredible amount of RPC traffic. Only the most recent open * directory is cached. This seems sufficient for most purposes. * Technically, we ought to flush the cache on close but this is * not a problem in practice. */ static int nfs_readdir(struct inode *inode, struct file *filp, void *dirent, filldir_t filldir) { static kdev_t c_dev = 0; static int c_ino; static int c_size; int result; int i, index = 0; struct nfs_entry *entry; if (!inode || !S_ISDIR(inode->i_mode)) { printk("nfs_readdir: inode is NULL or not a directory\n"); return -EBADF; } revalidate_dir(NFS_SERVER(inode), inode); /* initialize cache memory if it hasn't been used before */ if (c_entry == NULL) { i = sizeof (struct nfs_entry)*NFS_READDIR_CACHE_SIZE; c_entry = (struct nfs_entry *) kmalloc(i, GFP_KERNEL); if (c_entry == NULL) { printk("nfs_readdir: no MEMORY for cache\n"); return -ENOMEM; } for (i = 0; i < NFS_READDIR_CACHE_SIZE; i++) { c_entry[i].name = (char *) kmalloc(NFS_MAXNAMLEN + 1, GFP_KERNEL); if (c_entry[i].name == NULL) { printk("nfs_readdir: no MEMORY for cache\n"); while (--i>=0) kfree(c_entry[i].name); kfree(c_entry); c_entry = NULL; return -ENOMEM; } } } entry = NULL; /* try to find it in the cache */ if (inode->i_dev == c_dev && inode->i_ino == c_ino) { for (i = 0; i < c_size; i++) { if (filp->f_pos == c_entry[i].cookie) { if (i == c_size - 1) { if (c_entry[i].eof) return 0; } else entry = c_entry + (index = i + 1); break; } } } /* if we didn't find it in the cache, revert to an nfs call */ if (!entry) { result = nfs_proc_readdir(NFS_SERVER(inode), NFS_FH(inode), filp->f_pos, NFS_READDIR_CACHE_SIZE, c_entry); if (result < 0) { c_dev = 0; return result; } if (result > 0) { c_dev = inode->i_dev; c_ino = inode->i_ino; c_size = result; entry = c_entry + (index = 0); } } /* if we found it in the cache or from an nfs call, return results */ if (!entry) return 0; while (index < c_size) { int nextpos = entry->cookie; if (filldir(dirent, entry->name, strlen(entry->name), filp->f_pos, entry->fileid) < 0) break; filp->f_pos = nextpos; /* revalidate the cache if we slept in filldir() */ if (inode->i_dev != c_dev) break; if (inode->i_ino != c_ino) break; if (nextpos != entry->cookie) break; index++; entry++; } return 0; } /* * free cache memory * called from cleanup_module */ void nfs_kfree_cache(void) { int i; if (c_entry == NULL) return; for (i = 0; i < NFS_READDIR_CACHE_SIZE; i++) kfree(c_entry[i].name); kfree(c_entry); c_entry = NULL; } /* * Lookup caching is a big win for performance but this is just * a trial to see how well it works on a small scale. * For example, bash does a lookup on ".." 13 times for each path * element when running pwd. Yes, hard to believe but true. * Try pwd in a filesystem mounted with noac. * * It trades a little cpu time and memory for a lot of network bandwidth. * Since the cache is not hashed yet, it is a good idea not to make it too * large because every lookup looks through the entire cache even * though most of them will fail. */ static struct nfs_lookup_cache_entry { kdev_t dev; int inode; char filename[NFS_MAXNAMLEN + 1]; struct nfs_fh fhandle; struct nfs_fattr fattr; int expiration_date; } nfs_lookup_cache[NFS_LOOKUP_CACHE_SIZE]; static struct nfs_lookup_cache_entry *nfs_lookup_cache_index(struct inode *dir, const char *filename) { struct nfs_lookup_cache_entry *entry; int i; for (i = 0; i < NFS_LOOKUP_CACHE_SIZE; i++) { entry = nfs_lookup_cache + i; if (entry->dev == dir->i_dev && entry->inode == dir->i_ino && !strncmp(filename, entry->filename, NFS_MAXNAMLEN)) return entry; } return NULL; } static int nfs_lookup_cache_lookup(struct inode *dir, const char *filename, struct nfs_fh *fhandle, struct nfs_fattr *fattr) { static int nfs_lookup_cache_in_use = 0; struct nfs_lookup_cache_entry *entry; if (!nfs_lookup_cache_in_use) { memset(nfs_lookup_cache, 0, sizeof(nfs_lookup_cache)); nfs_lookup_cache_in_use = 1; } if ((entry = nfs_lookup_cache_index(dir, filename))) { if (jiffies > entry->expiration_date) { entry->dev = 0; return 0; } *fhandle = entry->fhandle; *fattr = entry->fattr; return 1; } return 0; } static void nfs_lookup_cache_add(struct inode *dir, const char *filename, struct nfs_fh *fhandle, struct nfs_fattr *fattr) { static int nfs_lookup_cache_pos = 0; struct nfs_lookup_cache_entry *entry; /* compensate for bug in SGI NFS server */ if (fattr->size == -1 || fattr->uid == -1 || fattr->gid == -1 || fattr->atime.seconds == -1 || fattr->mtime.seconds == -1) return; if (!(entry = nfs_lookup_cache_index(dir, filename))) { entry = nfs_lookup_cache + nfs_lookup_cache_pos++; if (nfs_lookup_cache_pos == NFS_LOOKUP_CACHE_SIZE) nfs_lookup_cache_pos = 0; } entry->dev = dir->i_dev; entry->inode = dir->i_ino; strcpy(entry->filename, filename); entry->fhandle = *fhandle; entry->fattr = *fattr; entry->expiration_date = jiffies + (S_ISDIR(fattr->mode) ? NFS_SERVER(dir)->acdirmin : NFS_SERVER(dir)->acregmin); } static void nfs_lookup_cache_remove(struct inode *dir, struct inode *inode, const char *filename) { struct nfs_lookup_cache_entry *entry; kdev_t dev; int fileid; int i; if (inode) { dev = inode->i_dev; fileid = inode->i_ino; } else if ((entry = nfs_lookup_cache_index(dir, filename))) { dev = entry->dev; fileid = entry->fattr.fileid; } else return; for (i = 0; i < NFS_LOOKUP_CACHE_SIZE; i++) { entry = nfs_lookup_cache + i; if (entry->dev == dev && entry->fattr.fileid == fileid) entry->dev = 0; } } static void nfs_lookup_cache_refresh(struct inode *file, struct nfs_fattr *fattr) { struct nfs_lookup_cache_entry *entry; kdev_t dev = file->i_dev; int fileid = file->i_ino; int i; for (i = 0; i < NFS_LOOKUP_CACHE_SIZE; i++) { entry = nfs_lookup_cache + i; if (entry->dev == dev && entry->fattr.fileid == fileid) entry->fattr = *fattr; } } static int nfs_lookup(struct inode *dir, const char *__name, int len, struct inode **result) { struct nfs_fh fhandle; struct nfs_fattr fattr; char name[len > NFS_MAXNAMLEN? 1 : len+1]; int error; *result = NULL; if (!dir || !S_ISDIR(dir->i_mode)) { printk("nfs_lookup: inode is NULL or not a directory\n"); iput(dir); return -ENOENT; } if (len > NFS_MAXNAMLEN) { iput(dir); return -ENAMETOOLONG; } memcpy(name,__name,len); name[len] = '\0'; if (len == 1 && name[0] == '.') { /* cheat for "." */ *result = dir; return 0; } if ((NFS_SERVER(dir)->flags & NFS_MOUNT_NOAC) || !nfs_lookup_cache_lookup(dir, name, &fhandle, &fattr)) { if ((error = nfs_proc_lookup(NFS_SERVER(dir), NFS_FH(dir), name, &fhandle, &fattr))) { iput(dir); return error; } nfs_lookup_cache_add(dir, name, &fhandle, &fattr); } if (!(*result = nfs_fhget(dir->i_sb, &fhandle, &fattr))) { iput(dir); return -EACCES; } iput(dir); return 0; } static int nfs_create(struct inode *dir, const char *name, int len, int mode, struct inode **result) { struct nfs_sattr sattr; struct nfs_fattr fattr; struct nfs_fh fhandle; int error; *result = NULL; if (!dir || !S_ISDIR(dir->i_mode)) { printk("nfs_create: inode is NULL or not a directory\n"); iput(dir); return -ENOENT; } if (len > NFS_MAXNAMLEN) { iput(dir); return -ENAMETOOLONG; } sattr.mode = mode; sattr.uid = sattr.gid = sattr.size = (unsigned) -1; sattr.atime.seconds = sattr.mtime.seconds = (unsigned) -1; if ((error = nfs_proc_create(NFS_SERVER(dir), NFS_FH(dir), name, &sattr, &fhandle, &fattr))) { iput(dir); return error; } if (!(*result = nfs_fhget(dir->i_sb, &fhandle, &fattr))) { iput(dir); return -EACCES; } nfs_lookup_cache_add(dir, name, &fhandle, &fattr); iput(dir); return 0; } static int nfs_mknod(struct inode *dir, const char *name, int len, int mode, int rdev) { struct nfs_sattr sattr; struct nfs_fattr fattr; struct nfs_fh fhandle; int error; if (!dir || !S_ISDIR(dir->i_mode)) { printk("nfs_mknod: inode is NULL or not a directory\n"); iput(dir); return -ENOENT; } if (len > NFS_MAXNAMLEN) { iput(dir); return -ENAMETOOLONG; } if (S_ISFIFO(mode)) sattr.mode = (mode & ~S_IFMT) | S_IFCHR; else sattr.mode = mode; sattr.uid = sattr.gid = (unsigned) -1; if (S_ISCHR(mode) || S_ISBLK(mode)) sattr.size = rdev; /* get out your barf bag */ else sattr.size = (unsigned) -1; sattr.atime.seconds = sattr.mtime.seconds = (unsigned) -1; error = nfs_proc_create(NFS_SERVER(dir), NFS_FH(dir), name, &sattr, &fhandle, &fattr); if (error == -EINVAL && (S_ISFIFO(mode))) { sattr.mode = mode; error = nfs_proc_create(NFS_SERVER(dir), NFS_FH(dir), name, &sattr, &fhandle, &fattr); } if (!error) { nfs_lookup_cache_add(dir, name, &fhandle, &fattr); /* The parent dir inode count may have changed ! */ nfs_lookup_cache_remove( NULL, dir, NULL); } iput(dir); return error; } static int nfs_mkdir(struct inode *dir, const char *name, int len, int mode) { struct nfs_sattr sattr; struct nfs_fattr fattr; struct nfs_fh fhandle; int error; if (!dir || !S_ISDIR(dir->i_mode)) { printk("nfs_mkdir: inode is NULL or not a directory\n"); iput(dir); return -ENOENT; } if (len > NFS_MAXNAMLEN) { iput(dir); return -ENAMETOOLONG; } sattr.mode = mode; sattr.uid = sattr.gid = sattr.size = (unsigned) -1; sattr.atime.seconds = sattr.mtime.seconds = (unsigned) -1; error = nfs_proc_mkdir(NFS_SERVER(dir), NFS_FH(dir), name, &sattr, &fhandle, &fattr); if (!error) { if (fattr.fileid == dir->i_ino) printk("Sony NewsOS 4.1R buggy nfs server?\n"); else nfs_lookup_cache_add(dir, name, &fhandle, &fattr); } iput(dir); /* The parent dir link count may have changed */ nfs_lookup_cache_remove( NULL, dir, NULL); return error; } static int nfs_rmdir(struct inode *dir, const char *name, int len) { int error; if (!dir || !S_ISDIR(dir->i_mode)) { printk("nfs_rmdir: inode is NULL or not a directory\n"); iput(dir); return -ENOENT; } if (len > NFS_MAXNAMLEN) { iput(dir); return -ENAMETOOLONG; } error = nfs_proc_rmdir(NFS_SERVER(dir), NFS_FH(dir), name); nfs_lookup_cache_remove(dir, NULL, name); iput(dir); return error; } static int nfs_sillyrename(struct inode *dir, const char *name, int len) { struct inode *inode; char silly[16]; int slen, ret; dir->i_count++; if (nfs_lookup(dir, name, len, &inode) < 0) return -EIO; /* arbitrary */ if (inode->i_count == 1 || NFS_RENAMED_DIR(inode)) { iput(inode); return -EIO; } slen = sprintf(silly, ".nfs%ld", inode->i_ino); if (len == slen && !strncmp(name, silly, len)) { iput(inode); return -EIO; /* DWIM */ } ret = nfs_proc_rename(NFS_SERVER(dir), NFS_FH(dir), name, NFS_FH(dir), silly, 0); if (ret >= 0) { nfs_lookup_cache_remove(dir, NULL, name); nfs_lookup_cache_remove(dir, NULL, silly); NFS_RENAMED_DIR(inode) = dir; dir->i_count++; } iput(inode); return ret; } void nfs_sillyrename_cleanup(struct inode *inode) { struct inode *dir = NFS_RENAMED_DIR(inode); char silly[14]; int error, slen; slen = sprintf(silly, ".nfs%ld", inode->i_ino); error = nfs_proc_remove(NFS_SERVER(dir), NFS_FH(dir), silly); nfs_lookup_cache_remove(dir, NULL, silly); if (error < 0) printk("NFS silly_rename cleanup failed (err = %d)\n", -error); NFS_RENAMED_DIR(inode) = NULL; iput(dir); } static int nfs_unlink(struct inode *dir, const char *name, int len) { int error; if (!dir || !S_ISDIR(dir->i_mode)) { printk("nfs_unlink: inode is NULL or not a directory\n"); iput(dir); return -ENOENT; } if (len > NFS_MAXNAMLEN) { iput(dir); return -ENAMETOOLONG; } if ((error = nfs_sillyrename(dir, name, len)) < 0) { error = nfs_proc_remove(NFS_SERVER(dir), NFS_FH(dir), name); nfs_lookup_cache_remove(dir, NULL, name); } iput(dir); return error; } static int nfs_symlink(struct inode *dir, const char *name, int len, const char *symname) { struct nfs_sattr sattr; int error; if (!dir || !S_ISDIR(dir->i_mode)) { printk("nfs_symlink: inode is NULL or not a directory\n"); iput(dir); return -ENOENT; } if (len > NFS_MAXNAMLEN) { iput(dir); return -ENAMETOOLONG; } if (strlen(symname) > NFS_MAXPATHLEN) { iput(dir); return -ENAMETOOLONG; } sattr.mode = S_IFLNK | S_IRWXUGO; /* SunOS 4.1.2 crashes without this! */ sattr.uid = sattr.gid = sattr.size = (unsigned) -1; sattr.atime.seconds = sattr.mtime.seconds = (unsigned) -1; error = nfs_proc_symlink(NFS_SERVER(dir), NFS_FH(dir), name, symname, &sattr); iput(dir); return error; } static int nfs_link(struct inode *oldinode, struct inode *dir, const char *name, int len) { int error; if (!oldinode) { printk("nfs_link: old inode is NULL\n"); iput(oldinode); iput(dir); return -ENOENT; } if (!dir || !S_ISDIR(dir->i_mode)) { printk("nfs_link: dir is NULL or not a directory\n"); iput(oldinode); iput(dir); return -ENOENT; } if (len > NFS_MAXNAMLEN) { iput(oldinode); iput(dir); return -ENAMETOOLONG; } error = nfs_proc_link(NFS_SERVER(oldinode), NFS_FH(oldinode), NFS_FH(dir), name); nfs_lookup_cache_remove(dir, oldinode, NULL); NFS_CACHEINV(oldinode); iput(oldinode); iput(dir); return error; } static int nfs_rename(struct inode *old_dir, const char *old_name, int old_len, struct inode *new_dir, const char *new_name, int new_len, int must_be_dir) { int error; if (!old_dir || !S_ISDIR(old_dir->i_mode)) { printk("nfs_rename: old inode is NULL or not a directory\n"); iput(old_dir); iput(new_dir); return -ENOENT; } if (!new_dir || !S_ISDIR(new_dir->i_mode)) { printk("nfs_rename: new inode is NULL or not a directory\n"); iput(old_dir); iput(new_dir); return -ENOENT; } if (old_len > NFS_MAXNAMLEN || new_len > NFS_MAXNAMLEN) { iput(old_dir); iput(new_dir); return -ENAMETOOLONG; } error = nfs_proc_rename(NFS_SERVER(old_dir), NFS_FH(old_dir), old_name, NFS_FH(new_dir), new_name, must_be_dir); nfs_lookup_cache_remove(old_dir, NULL, old_name); nfs_lookup_cache_remove(new_dir, NULL, new_name); iput(old_dir); iput(new_dir); return error; } /* * Many nfs protocol calls return the new file attributes after * an operation. Here we update the inode to reflect the state * of the server's inode. */ void nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr) { int was_empty; if (!inode || !fattr) { printk("nfs_refresh_inode: inode or fattr is NULL\n"); return; } if (inode->i_ino != fattr->fileid) { printk("nfs_refresh_inode: inode number mismatch\n"); return; } was_empty = (inode->i_mode == 0); /* * Some (broken?) NFS servers return 0 as the file type. * We'll assume that 0 means the file type has not changed. */ if(!(fattr->mode & S_IFMT)){ inode->i_mode = (inode->i_mode & S_IFMT) | (fattr->mode & ~S_IFMT); }else{ inode->i_mode = fattr->mode; } inode->i_nlink = fattr->nlink; inode->i_uid = fattr->uid; inode->i_gid = fattr->gid; /* Size changed from outside: invalidate caches on next read */ if (inode->i_size != fattr->size) NFS_CACHEINV(inode); if (NFS_OLDMTIME(inode) != fattr->mtime.seconds) NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode); inode->i_size = fattr->size; if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) inode->i_rdev = to_kdev_t(fattr->rdev); else inode->i_rdev = 0; inode->i_blocks = fattr->blocks; inode->i_atime = fattr->atime.seconds; inode->i_mtime = fattr->mtime.seconds; inode->i_ctime = fattr->ctime.seconds; if (S_ISREG(inode->i_mode)) inode->i_op = &nfs_file_inode_operations; else if (S_ISDIR(inode->i_mode)) inode->i_op = &nfs_dir_inode_operations; else if (S_ISLNK(inode->i_mode)) inode->i_op = &nfs_symlink_inode_operations; else if (S_ISCHR(inode->i_mode)) inode->i_op = &chrdev_inode_operations; else if (S_ISBLK(inode->i_mode)) inode->i_op = &blkdev_inode_operations; else if (S_ISFIFO(inode->i_mode)) { if (was_empty) init_fifo(inode); } else inode->i_op = NULL; nfs_lookup_cache_refresh(inode, fattr); }