/*
 *  dir.c
 *
 *  Copyright (C) 1995, 1996 by Volker Lendecke
 *  Modified for big endian by J.F. Chadima and David S. Miller
 *  Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
 *  Modified 1998, 1999 Wolfram Pienkoss for NLS
 *  Modified 1999 Wolfram Pienkoss for directory caching
 *  Modified 2000 Ben Harris, University of Cambridge for NFS NS meta-info
 *
 */


#include <linux/time.h>
#include <linux/errno.h>
#include <linux/stat.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
#include <linux/smp_lock.h>

#include <linux/ncp_fs.h>

#include "ncplib_kernel.h"

static void ncp_read_volume_list(struct file *, void *, filldir_t,
                                struct ncp_cache_control *);
static void ncp_do_readdir(struct file *, void *, filldir_t,
                                struct ncp_cache_control *);

static int ncp_readdir(struct file *, void *, filldir_t);

static int ncp_create(struct inode *, struct dentry *, int, struct nameidata *);
static struct dentry *ncp_lookup(struct inode *, struct dentry *, struct nameidata *);
static int ncp_unlink(struct inode *, struct dentry *);
static int ncp_mkdir(struct inode *, struct dentry *, int);
static int ncp_rmdir(struct inode *, struct dentry *);
static int ncp_rename(struct inode *, struct dentry *,
                      struct inode *, struct dentry *);
static int ncp_mknod(struct inode * dir, struct dentry *dentry,
                     int mode, dev_t rdev);
#if defined(CONFIG_NCPFS_EXTRAS) || defined(CONFIG_NCPFS_NFS_NS)
extern int ncp_symlink(struct inode *, struct dentry *, const char *);
#else
#define ncp_symlink NULL
#endif
                      
const struct file_operations ncp_dir_operations =
{
        .read           = generic_read_dir,
        .readdir        = ncp_readdir,
        .ioctl          = ncp_ioctl,
#ifdef CONFIG_COMPAT
        .compat_ioctl   = ncp_compat_ioctl,
#endif
};

const struct inode_operations ncp_dir_inode_operations =
{
        .create         = ncp_create,
        .lookup         = ncp_lookup,
        .unlink         = ncp_unlink,
        .symlink        = ncp_symlink,
        .mkdir          = ncp_mkdir,
        .rmdir          = ncp_rmdir,
        .mknod          = ncp_mknod,
        .rename         = ncp_rename,
        .setattr        = ncp_notify_change,
};

/*
 * Dentry operations routines
 */
static int ncp_lookup_validate(struct dentry *, struct nameidata *);
static int ncp_hash_dentry(struct dentry *, struct qstr *);
static int ncp_compare_dentry (struct dentry *, struct qstr *, struct qstr *);
static int ncp_delete_dentry(struct dentry *);

static struct dentry_operations ncp_dentry_operations =
{
        .d_revalidate   = ncp_lookup_validate,
        .d_hash         = ncp_hash_dentry,
        .d_compare      = ncp_compare_dentry,
        .d_delete       = ncp_delete_dentry,
};

struct dentry_operations ncp_root_dentry_operations =
{
        .d_hash         = ncp_hash_dentry,
        .d_compare      = ncp_compare_dentry,
        .d_delete       = ncp_delete_dentry,
};


/*
 * Note: leave the hash unchanged if the directory
 * is case-sensitive.
 */
static int 
ncp_hash_dentry(struct dentry *dentry, struct qstr *this)
{
        struct nls_table *t;
        unsigned long hash;
        int i;

        t = NCP_IO_TABLE(dentry);

        if (!ncp_case_sensitive(dentry->d_inode)) {
                hash = init_name_hash();
                for (i=0; i<this->len ; i++)
                        hash = partial_name_hash(ncp_tolower(t, this->name[i]),
                                                                        hash);
                this->hash = end_name_hash(hash);
        }
        return 0;
}

static int
ncp_compare_dentry(struct dentry *dentry, struct qstr *a, struct qstr *b)
{
        if (a->len != b->len)
                return 1;

        if (ncp_case_sensitive(dentry->d_inode))
                return strncmp(a->name, b->name, a->len);

        return ncp_strnicmp(NCP_IO_TABLE(dentry), a->name, b->name, a->len);
}

/*
 * This is the callback from dput() when d_count is going to 0.
 * We use this to unhash dentries with bad inodes.
 * Closing files can be safely postponed until iput() - it's done there anyway.
 */
static int
ncp_delete_dentry(struct dentry * dentry)
{
        struct inode *inode = dentry->d_inode;

        if (inode) {
                if (is_bad_inode(inode))
                        return 1;
        } else
        {
        /* N.B. Unhash negative dentries? */
        }
        return 0;
}

static inline int
ncp_single_volume(struct ncp_server *server)
{
        return (server->m.mounted_vol[0] != '\0');
}

static inline int ncp_is_server_root(struct inode *inode)
{
        return (!ncp_single_volume(NCP_SERVER(inode)) &&
                inode == inode->i_sb->s_root->d_inode);
}


/*
 * This is the callback when the dcache has a lookup hit.
 */


#ifdef CONFIG_NCPFS_STRONG
/* try to delete a readonly file (NW R bit set) */

static int
ncp_force_unlink(struct inode *dir, struct dentry* dentry)
{
        int res=0x9c,res2;
        struct nw_modify_dos_info info;
        __le32 old_nwattr;
        struct inode *inode;

        memset(&info, 0, sizeof(info));
        
        /* remove the Read-Only flag on the NW server */
        inode = dentry->d_inode;

        old_nwattr = NCP_FINFO(inode)->nwattr;
        info.attributes = old_nwattr & ~(aRONLY|aDELETEINHIBIT|aRENAMEINHIBIT);
        res2 = ncp_modify_file_or_subdir_dos_info_path(NCP_SERVER(inode), inode, NULL, DM_ATTRIBUTES, &info);
        if (res2)
                goto leave_me;

        /* now try again the delete operation */
        res = ncp_del_file_or_subdir2(NCP_SERVER(dir), dentry);

        if (res)  /* delete failed, set R bit again */
        {
                info.attributes = old_nwattr;
                res2 = ncp_modify_file_or_subdir_dos_info_path(NCP_SERVER(inode), inode, NULL, DM_ATTRIBUTES, &info);
                if (res2)
                        goto leave_me;
        }
leave_me:
        return(res);
}
#endif  /* CONFIG_NCPFS_STRONG */

#ifdef CONFIG_NCPFS_STRONG
static int
ncp_force_rename(struct inode *old_dir, struct dentry* old_dentry, char *_old_name,
                 struct inode *new_dir, struct dentry* new_dentry, char *_new_name)
{
        struct nw_modify_dos_info info;
        int res=0x90,res2;
        struct inode *old_inode = old_dentry->d_inode;
        __le32 old_nwattr = NCP_FINFO(old_inode)->nwattr;
        __le32 new_nwattr = 0; /* shut compiler warning */
        int old_nwattr_changed = 0;
        int new_nwattr_changed = 0;

        memset(&info, 0, sizeof(info));
        
        /* remove the Read-Only flag on the NW server */

        info.attributes = old_nwattr & ~(aRONLY|aRENAMEINHIBIT|aDELETEINHIBIT);
        res2 = ncp_modify_file_or_subdir_dos_info_path(NCP_SERVER(old_inode), old_inode, NULL, DM_ATTRIBUTES, &info);
        if (!res2)
                old_nwattr_changed = 1;
        if (new_dentry && new_dentry->d_inode) {
                new_nwattr = NCP_FINFO(new_dentry->d_inode)->nwattr;
                info.attributes = new_nwattr & ~(aRONLY|aRENAMEINHIBIT|aDELETEINHIBIT);
                res2 = ncp_modify_file_or_subdir_dos_info_path(NCP_SERVER(new_dir), new_dir, _new_name, DM_ATTRIBUTES, &info);
                if (!res2)
                        new_nwattr_changed = 1;
        }
        /* now try again the rename operation */
        /* but only if something really happened */
        if (new_nwattr_changed || old_nwattr_changed) {
                res = ncp_ren_or_mov_file_or_subdir(NCP_SERVER(old_dir),
                                                    old_dir, _old_name,
                                                    new_dir, _new_name);
        } 
        if (res)
                goto leave_me;
        /* file was successfully renamed, so:
           do not set attributes on old file - it no longer exists
           copy attributes from old file to new */
        new_nwattr_changed = old_nwattr_changed;
        new_nwattr = old_nwattr;
        old_nwattr_changed = 0;
        
leave_me:;
        if (old_nwattr_changed) {
                info.attributes = old_nwattr;
                res2 = ncp_modify_file_or_subdir_dos_info_path(NCP_SERVER(old_inode), old_inode, NULL, DM_ATTRIBUTES, &info);
                /* ignore errors */
        }
        if (new_nwattr_changed) {
                info.attributes = new_nwattr;
                res2 = ncp_modify_file_or_subdir_dos_info_path(NCP_SERVER(new_dir), new_dir, _new_name, DM_ATTRIBUTES, &info);
                /* ignore errors */
        }
        return(res);
}
#endif  /* CONFIG_NCPFS_STRONG */


static int
__ncp_lookup_validate(struct dentry * dentry, struct nameidata *nd)
{
        struct ncp_server *server;
        struct dentry *parent;
        struct inode *dir;
        struct ncp_entry_info finfo;
        int res, val = 0, len;
        __u8 __name[NCP_MAXPATHLEN + 1];

        parent = dget_parent(dentry);
        dir = parent->d_inode;

        if (!dentry->d_inode)
                goto finished;

        server = NCP_SERVER(dir);

        if (!ncp_conn_valid(server))
                goto finished;

        /*
         * Inspired by smbfs:
         * The default validation is based on dentry age:
         * We set the max age at mount time.  (But each
         * successful server lookup renews the timestamp.)
         */
        val = NCP_TEST_AGE(server, dentry);
        if (val)
                goto finished;

        DDPRINTK("ncp_lookup_validate: %s/%s not valid, age=%ld, server lookup\n",
                dentry->d_parent->d_name.name, dentry->d_name.name,
                NCP_GET_AGE(dentry));

        len = sizeof(__name);
        if (ncp_is_server_root(dir)) {
                res = ncp_io2vol(server, __name, &len, dentry->d_name.name,
                                 dentry->d_name.len, 1);
                if (!res)
                        res = ncp_lookup_volume(server, __name, &(finfo.i));
        } else {
                res = ncp_io2vol(server, __name, &len, dentry->d_name.name,
                                 dentry->d_name.len, !ncp_preserve_case(dir));
                if (!res)
                        res = ncp_obtain_info(server, dir, __name, &(finfo.i));
        }
        finfo.volume = finfo.i.volNumber;
        DDPRINTK("ncp_lookup_validate: looked for %s/%s, res=%d\n",
                dentry->d_parent->d_name.name, __name, res);
        /*
         * If we didn't find it, or if it has a different dirEntNum to
         * what we remember, it's not valid any more.
         */
        if (!res) {
                if (finfo.i.dirEntNum == NCP_FINFO(dentry->d_inode)->dirEntNum) {
                        ncp_new_dentry(dentry);
                        val=1;
                } else
                        DDPRINTK("ncp_lookup_validate: found, but dirEntNum changed\n");

                ncp_update_inode2(dentry->d_inode, &finfo);
        }

finished:
        DDPRINTK("ncp_lookup_validate: result=%d\n", val);
        dput(parent);
        return val;
}

static int
ncp_lookup_validate(struct dentry * dentry, struct nameidata *nd)
{
        int res;
        lock_kernel();
        res = __ncp_lookup_validate(dentry, nd);
        unlock_kernel();
        return res;
}

static struct dentry *
ncp_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos)
{
        struct dentry *dent = dentry;
        struct list_head *next;

        if (d_validate(dent, parent)) {
                if (dent->d_name.len <= NCP_MAXPATHLEN &&
                    (unsigned long)dent->d_fsdata == fpos) {
                        if (!dent->d_inode) {
                                dput(dent);
                                dent = NULL;
                        }
                        return dent;
                }
                dput(dent);
        }

        /* If a pointer is invalid, we search the dentry. */
        spin_lock(&dcache_lock);
        next = parent->d_subdirs.next;
        while (next != &parent->d_subdirs) {
                dent = list_entry(next, struct dentry, d_u.d_child);
                if ((unsigned long)dent->d_fsdata == fpos) {
                        if (dent->d_inode)
                                dget_locked(dent);
                        else
                                dent = NULL;
                        spin_unlock(&dcache_lock);
                        goto out;
                }
                next = next->next;
        }
        spin_unlock(&dcache_lock);
        return NULL;

out:
        return dent;
}

static time_t ncp_obtain_mtime(struct dentry *dentry)
{
        struct inode *inode = dentry->d_inode;
        struct ncp_server *server = NCP_SERVER(inode);
        struct nw_info_struct i;

        if (!ncp_conn_valid(server) || ncp_is_server_root(inode))
                return 0;

        if (ncp_obtain_info(server, inode, NULL, &i))
                return 0;

        return ncp_date_dos2unix(i.modifyTime, i.modifyDate);
}

static int ncp_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
        struct dentry *dentry = filp->f_path.dentry;
        struct inode *inode = dentry->d_inode;
        struct page *page = NULL;
        struct ncp_server *server = NCP_SERVER(inode);
        union  ncp_dir_cache *cache = NULL;
        struct ncp_cache_control ctl;
        int result, mtime_valid = 0;
        time_t mtime = 0;

        lock_kernel();

        ctl.page  = NULL;
        ctl.cache = NULL;

        DDPRINTK("ncp_readdir: reading %s/%s, pos=%d\n",
                dentry->d_parent->d_name.name, dentry->d_name.name,
                (int) filp->f_pos);

        result = -EIO;
        if (!ncp_conn_valid(server))
                goto out;

        result = 0;
        if (filp->f_pos == 0) {
                if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR))
                        goto out;
                filp->f_pos = 1;
        }
        if (filp->f_pos == 1) {
                if (filldir(dirent, "..", 2, 1, parent_ino(dentry), DT_DIR))
                        goto out;
                filp->f_pos = 2;
        }

        page = grab_cache_page(&inode->i_data, 0);
        if (!page)
                goto read_really;

        ctl.cache = cache = kmap(page);
        ctl.head  = cache->head;

        if (!PageUptodate(page) || !ctl.head.eof)
                goto init_cache;

        if (filp->f_pos == 2) {
                if (jiffies - ctl.head.time >= NCP_MAX_AGE(server))
                        goto init_cache;

                mtime = ncp_obtain_mtime(dentry);
                mtime_valid = 1;
                if ((!mtime) || (mtime != ctl.head.mtime))
                        goto init_cache;
        }

        if (filp->f_pos > ctl.head.end)
                goto finished;

        ctl.fpos = filp->f_pos + (NCP_DIRCACHE_START - 2);
        ctl.ofs  = ctl.fpos / NCP_DIRCACHE_SIZE;
        ctl.idx  = ctl.fpos % NCP_DIRCACHE_SIZE;

        for (;;) {
                if (ctl.ofs != 0) {
                        ctl.page = find_lock_page(&inode->i_data, ctl.ofs);
                        if (!ctl.page)
                                goto invalid_cache;
                        ctl.cache = kmap(ctl.page);
                        if (!PageUptodate(ctl.page))
                                goto invalid_cache;
                }
                while (ctl.idx < NCP_DIRCACHE_SIZE) {
                        struct dentry *dent;
                        int res;

                        dent = ncp_dget_fpos(ctl.cache->dentry[ctl.idx],
                                                dentry, filp->f_pos);
                        if (!dent)
                                goto invalid_cache;
                        res = filldir(dirent, dent->d_name.name,
                                        dent->d_name.len, filp->f_pos,
                                        dent->d_inode->i_ino, DT_UNKNOWN);
                        dput(dent);
                        if (res)
                                goto finished;
                        filp->f_pos += 1;
                        ctl.idx += 1;
                        if (filp->f_pos > ctl.head.end)
                                goto finished;
                }
                if (ctl.page) {
                        kunmap(ctl.page);
                        SetPageUptodate(ctl.page);
                        unlock_page(ctl.page);
                        page_cache_release(ctl.page);
                        ctl.page = NULL;
                }
                ctl.idx  = 0;
                ctl.ofs += 1;
        }
invalid_cache:
        if (ctl.page) {
                kunmap(ctl.page);
                unlock_page(ctl.page);
                page_cache_release(ctl.page);
                ctl.page = NULL;
        }
        ctl.cache = cache;
init_cache:
        ncp_invalidate_dircache_entries(dentry);
        if (!mtime_valid) {
                mtime = ncp_obtain_mtime(dentry);
                mtime_valid = 1;
        }
        ctl.head.mtime = mtime;
        ctl.head.time = jiffies;
        ctl.head.eof = 0;
        ctl.fpos = 2;
        ctl.ofs = 0;
        ctl.idx = NCP_DIRCACHE_START;
        ctl.filled = 0;
        ctl.valid  = 1;
read_really:
        if (ncp_is_server_root(inode)) {
                ncp_read_volume_list(filp, dirent, filldir, &ctl);
        } else {
                ncp_do_readdir(filp, dirent, filldir, &ctl);
        }
        ctl.head.end = ctl.fpos - 1;
        ctl.head.eof = ctl.valid;
finished:
        if (page) {
                cache->head = ctl.head;
                kunmap(page);
                SetPageUptodate(page);
                unlock_page(page);
                page_cache_release(page);
        }
        if (ctl.page) {
                kunmap(ctl.page);
                SetPageUptodate(ctl.page);
                unlock_page(ctl.page);
                page_cache_release(ctl.page);
        }
out:
        unlock_kernel();
        return result;
}

static int
ncp_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
                struct ncp_cache_control *ctrl, struct ncp_entry_info *entry)
{
        struct dentry *newdent, *dentry = filp->f_path.dentry;
        struct inode *newino, *inode = dentry->d_inode;
        struct ncp_cache_control ctl = *ctrl;
        struct qstr qname;
        int valid = 0;
        int hashed = 0;
        ino_t ino = 0;
        __u8 __name[NCP_MAXPATHLEN + 1];

        qname.len = sizeof(__name);
        if (ncp_vol2io(NCP_SERVER(inode), __name, &qname.len,
                        entry->i.entryName, entry->i.nameLen,
                        !ncp_preserve_entry_case(inode, entry->i.NSCreator)))
                return 1; /* I'm not sure */

        qname.name = __name;
        qname.hash = full_name_hash(qname.name, qname.len);

        if (dentry->d_op && dentry->d_op->d_hash)
                if (dentry->d_op->d_hash(dentry, &qname) != 0)
                        goto end_advance;

        newdent = d_lookup(dentry, &qname);

        if (!newdent) {
                newdent = d_alloc(dentry, &qname);
                if (!newdent)
                        goto end_advance;
        } else {
                hashed = 1;
                memcpy((char *) newdent->d_name.name, qname.name,
                                                        newdent->d_name.len);
        }

        if (!newdent->d_inode) {
                entry->opened = 0;
                entry->ino = iunique(inode->i_sb, 2);
                newino = ncp_iget(inode->i_sb, entry);
                if (newino) {
                        newdent->d_op = &ncp_dentry_operations;
                        d_instantiate(newdent, newino);
                        if (!hashed)
                                d_rehash(newdent);
                }
        } else
                ncp_update_inode2(newdent->d_inode, entry);

        if (newdent->d_inode) {
                ino = newdent->d_inode->i_ino;
                newdent->d_fsdata = (void *) ctl.fpos;
                ncp_new_dentry(newdent);
        }

        if (ctl.idx >= NCP_DIRCACHE_SIZE) {
                if (ctl.page) {
                        kunmap(ctl.page);
                        SetPageUptodate(ctl.page);
                        unlock_page(ctl.page);
                        page_cache_release(ctl.page);
                }
                ctl.cache = NULL;
                ctl.idx  -= NCP_DIRCACHE_SIZE;
                ctl.ofs  += 1;
                ctl.page  = grab_cache_page(&inode->i_data, ctl.ofs);
                if (ctl.page)
                        ctl.cache = kmap(ctl.page);
        }
        if (ctl.cache) {
                ctl.cache->dentry[ctl.idx] = newdent;
                valid = 1;
        }
        dput(newdent);
end_advance:
        if (!valid)
                ctl.valid = 0;
        if (!ctl.filled && (ctl.fpos == filp->f_pos)) {
                if (!ino)
                        ino = find_inode_number(dentry, &qname);
                if (!ino)
                        ino = iunique(inode->i_sb, 2);
                ctl.filled = filldir(dirent, qname.name, qname.len,
                                     filp->f_pos, ino, DT_UNKNOWN);
                if (!ctl.filled)
                        filp->f_pos += 1;
        }
        ctl.fpos += 1;
        ctl.idx  += 1;
        *ctrl = ctl;
        return (ctl.valid || !ctl.filled);
}

static void
ncp_read_volume_list(struct file *filp, void *dirent, filldir_t filldir,
                        struct ncp_cache_control *ctl)
{
        struct dentry *dentry = filp->f_path.dentry;
        struct inode *inode = dentry->d_inode;
        struct ncp_server *server = NCP_SERVER(inode);
        struct ncp_volume_info info;
        struct ncp_entry_info entry;
        int i;

        DPRINTK("ncp_read_volume_list: pos=%ld\n",
                        (unsigned long) filp->f_pos);

        for (i = 0; i < NCP_NUMBER_OF_VOLUMES; i++) {

                if (ncp_get_volume_info_with_number(server, i, &info) != 0)
                        return;
                if (!strlen(info.volume_name))
                        continue;

                DPRINTK("ncp_read_volume_list: found vol: %s\n",
                        info.volume_name);

                if (ncp_lookup_volume(server, info.volume_name,
                                        &entry.i)) {
                        DPRINTK("ncpfs: could not lookup vol %s\n",
                                info.volume_name);
                        continue;
                }
                entry.volume = entry.i.volNumber;
                if (!ncp_fill_cache(filp, dirent, filldir, ctl, &entry))
                        return;
        }
}

static void
ncp_do_readdir(struct file *filp, void *dirent, filldir_t filldir,
                                                struct ncp_cache_control *ctl)
{
        struct dentry *dentry = filp->f_path.dentry;
        struct inode *dir = dentry->d_inode;
        struct ncp_server *server = NCP_SERVER(dir);
        struct nw_search_sequence seq;
        struct ncp_entry_info entry;
        int err;
        void* buf;
        int more;
        size_t bufsize;

        DPRINTK("ncp_do_readdir: %s/%s, fpos=%ld\n",
                dentry->d_parent->d_name.name, dentry->d_name.name,
                (unsigned long) filp->f_pos);
        PPRINTK("ncp_do_readdir: init %s, volnum=%d, dirent=%u\n",
                dentry->d_name.name, NCP_FINFO(dir)->volNumber,
                NCP_FINFO(dir)->dirEntNum);

        err = ncp_initialize_search(server, dir, &seq);
        if (err) {
                DPRINTK("ncp_do_readdir: init failed, err=%d\n", err);
                return;
        }
        /* We MUST NOT use server->buffer_size handshaked with server if we are
           using UDP, as for UDP server uses max. buffer size determined by
           MTU, and for TCP server uses hardwired value 65KB (== 66560 bytes). 
           So we use 128KB, just to be sure, as there is no way how to know
           this value in advance. */
        bufsize = 131072;
        buf = vmalloc(bufsize);
        if (!buf)
                return;
        do {
                int cnt;
                char* rpl;
                size_t rpls;

                err = ncp_search_for_fileset(server, &seq, &more, &cnt, buf, bufsize, &rpl, &rpls);
                if (err)                /* Error */
                        break;
                if (!cnt)               /* prevent endless loop */
                        break;
                while (cnt--) {
                        size_t onerpl;
                        
                        if (rpls < offsetof(struct nw_info_struct, entryName))
                                break;  /* short packet */
                        ncp_extract_file_info(rpl, &entry.i);
                        onerpl = offsetof(struct nw_info_struct, entryName) + entry.i.nameLen;
                        if (rpls < onerpl)
                                break;  /* short packet */
                        (void)ncp_obtain_nfs_info(server, &entry.i);
                        rpl += onerpl;
                        rpls -= onerpl;
                        entry.volume = entry.i.volNumber;
                        if (!ncp_fill_cache(filp, dirent, filldir, ctl, &entry))
                                break;
                }
        } while (more);
        vfree(buf);
        return;
}

int ncp_conn_logged_in(struct super_block *sb)
{
        struct ncp_server* server = NCP_SBP(sb);
        int result;

        if (ncp_single_volume(server)) {
                int len;
                struct dentry* dent;
                __u32 volNumber;
                __le32 dirEntNum;
                __le32 DosDirNum;
                __u8 __name[NCP_MAXPATHLEN + 1];

                len = sizeof(__name);
                result = ncp_io2vol(server, __name, &len, server->m.mounted_vol,
                                    strlen(server->m.mounted_vol), 1);
                if (result)
                        goto out;
                result = -ENOENT;
                if (ncp_get_volume_root(server, __name, &volNumber, &dirEntNum, &DosDirNum)) {
                        PPRINTK("ncp_conn_logged_in: %s not found\n",
                                server->m.mounted_vol);
                        goto out;
                }
                dent = sb->s_root;
                if (dent) {
                        struct inode* ino = dent->d_inode;
                        if (ino) {
                                NCP_FINFO(ino)->volNumber = volNumber;
                                NCP_FINFO(ino)->dirEntNum = dirEntNum;
                                NCP_FINFO(ino)->DosDirNum = DosDirNum;
                        } else {
                                DPRINTK("ncpfs: sb->s_root->d_inode == NULL!\n");
                        }
                } else {
                        DPRINTK("ncpfs: sb->s_root == NULL!\n");
                }
        }
        result = 0;

out:
        return result;
}

static struct dentry *ncp_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
{
        struct ncp_server *server = NCP_SERVER(dir);
        struct inode *inode = NULL;
        struct ncp_entry_info finfo;
        int error, res, len;
        __u8 __name[NCP_MAXPATHLEN + 1];

        lock_kernel();
        error = -EIO;
        if (!ncp_conn_valid(server))
                goto finished;

        PPRINTK("ncp_lookup: server lookup for %s/%s\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);

        len = sizeof(__name);
        if (ncp_is_server_root(dir)) {
                res = ncp_io2vol(server, __name, &len, dentry->d_name.name,
                                 dentry->d_name.len, 1);
                if (!res)
                        res = ncp_lookup_volume(server, __name, &(finfo.i));
        } else {
                res = ncp_io2vol(server, __name, &len, dentry->d_name.name,
                                 dentry->d_name.len, !ncp_preserve_case(dir));
                if (!res)
                        res = ncp_obtain_info(server, dir, __name, &(finfo.i));
        }
        PPRINTK("ncp_lookup: looked for %s/%s, res=%d\n",
                dentry->d_parent->d_name.name, __name, res);
        /*
         * If we didn't find an entry, make a negative dentry.
         */
        if (res)
                goto add_entry;

        /*
         * Create an inode for the entry.
         */
        finfo.opened = 0;
        finfo.ino = iunique(dir->i_sb, 2);
        finfo.volume = finfo.i.volNumber;
        error = -EACCES;
        inode = ncp_iget(dir->i_sb, &finfo);

        if (inode) {
                ncp_new_dentry(dentry);
add_entry:
                dentry->d_op = &ncp_dentry_operations;
                d_add(dentry, inode);
                error = 0;
        }

finished:
        PPRINTK("ncp_lookup: result=%d\n", error);
        unlock_kernel();
        return ERR_PTR(error);
}

/*
 * This code is common to create, mkdir, and mknod.
 */
static int ncp_instantiate(struct inode *dir, struct dentry *dentry,
                        struct ncp_entry_info *finfo)
{
        struct inode *inode;
        int error = -EINVAL;

        finfo->ino = iunique(dir->i_sb, 2);
        inode = ncp_iget(dir->i_sb, finfo);
        if (!inode)
                goto out_close;
        d_instantiate(dentry,inode);
        error = 0;
out:
        return error;

out_close:
        PPRINTK("ncp_instantiate: %s/%s failed, closing file\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);
        ncp_close_file(NCP_SERVER(dir), finfo->file_handle);
        goto out;
}

int ncp_create_new(struct inode *dir, struct dentry *dentry, int mode,
                   dev_t rdev, __le32 attributes)
{
        struct ncp_server *server = NCP_SERVER(dir);
        struct ncp_entry_info finfo;
        int error, result, len;
        int opmode;
        __u8 __name[NCP_MAXPATHLEN + 1];
        
        PPRINTK("ncp_create_new: creating %s/%s, mode=%x\n",
                dentry->d_parent->d_name.name, dentry->d_name.name, mode);

        error = -EIO;
        lock_kernel();
        if (!ncp_conn_valid(server))
                goto out;

        ncp_age_dentry(server, dentry);
        len = sizeof(__name);
        error = ncp_io2vol(server, __name, &len, dentry->d_name.name,
                           dentry->d_name.len, !ncp_preserve_case(dir));
        if (error)
                goto out;

        error = -EACCES;
        
        if (S_ISREG(mode) && 
            (server->m.flags & NCP_MOUNT_EXTRAS) && 
            (mode & S_IXUGO))
                attributes |= aSYSTEM | aSHARED;
        
        result = ncp_open_create_file_or_subdir(server, dir, __name,
                                OC_MODE_CREATE | OC_MODE_OPEN | OC_MODE_REPLACE,
                                attributes, AR_READ | AR_WRITE, &finfo);
        opmode = O_RDWR;
        if (result) {
                result = ncp_open_create_file_or_subdir(server, dir, __name,
                                OC_MODE_CREATE | OC_MODE_OPEN | OC_MODE_REPLACE,
                                attributes, AR_WRITE, &finfo);
                if (result) {
                        if (result == 0x87)
                                error = -ENAMETOOLONG;
                        DPRINTK("ncp_create: %s/%s failed\n",
                                dentry->d_parent->d_name.name, dentry->d_name.name);
                        goto out;
                }
                opmode = O_WRONLY;
        }
        finfo.access = opmode;
        if (ncp_is_nfs_extras(server, finfo.volume)) {
                finfo.i.nfs.mode = mode;
                finfo.i.nfs.rdev = new_encode_dev(rdev);
                if (ncp_modify_nfs_info(server, finfo.volume,
                                        finfo.i.dirEntNum,
                                        mode, new_encode_dev(rdev)) != 0)
                        goto out;
        }

        error = ncp_instantiate(dir, dentry, &finfo);
out:
        unlock_kernel();
        return error;
}

static int ncp_create(struct inode *dir, struct dentry *dentry, int mode,
                struct nameidata *nd)
{
        return ncp_create_new(dir, dentry, mode, 0, 0);
}

static int ncp_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
        struct ncp_entry_info finfo;
        struct ncp_server *server = NCP_SERVER(dir);
        int error, len;
        __u8 __name[NCP_MAXPATHLEN + 1];

        DPRINTK("ncp_mkdir: making %s/%s\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);

        error = -EIO;
        lock_kernel();
        if (!ncp_conn_valid(server))
                goto out;

        ncp_age_dentry(server, dentry);
        len = sizeof(__name);
        error = ncp_io2vol(server, __name, &len, dentry->d_name.name,
                           dentry->d_name.len, !ncp_preserve_case(dir));
        if (error)
                goto out;

        error = -EACCES;
        if (ncp_open_create_file_or_subdir(server, dir, __name,
                                           OC_MODE_CREATE, aDIR,
                                           cpu_to_le16(0xffff),
                                           &finfo) == 0)
        {
                if (ncp_is_nfs_extras(server, finfo.volume)) {
                        mode |= S_IFDIR;
                        finfo.i.nfs.mode = mode;
                        if (ncp_modify_nfs_info(server,
                                                finfo.volume,
                                                finfo.i.dirEntNum,
                                                mode, 0) != 0)
                                goto out;
                }
                error = ncp_instantiate(dir, dentry, &finfo);
        }
out:
        unlock_kernel();
        return error;
}

static int ncp_rmdir(struct inode *dir, struct dentry *dentry)
{
        struct ncp_server *server = NCP_SERVER(dir);
        int error, result, len;
        __u8 __name[NCP_MAXPATHLEN + 1];

        DPRINTK("ncp_rmdir: removing %s/%s\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);

        error = -EIO;
        lock_kernel();
        if (!ncp_conn_valid(server))
                goto out;

        error = -EBUSY;
        if (!d_unhashed(dentry))
                goto out;

        len = sizeof(__name);
        error = ncp_io2vol(server, __name, &len, dentry->d_name.name,
                           dentry->d_name.len, !ncp_preserve_case(dir));
        if (error)
                goto out;

        result = ncp_del_file_or_subdir(server, dir, __name);
        switch (result) {
                case 0x00:
                        error = 0;
                        break;
                case 0x85:      /* unauthorized to delete file */
                case 0x8A:      /* unauthorized to delete file */
                        error = -EACCES;
                        break;
                case 0x8F:
                case 0x90:      /* read only */
                        error = -EPERM;
                        break;
                case 0x9F:      /* in use by another client */
                        error = -EBUSY;
                        break;
                case 0xA0:      /* directory not empty */
                        error = -ENOTEMPTY;
                        break;
                case 0xFF:      /* someone deleted file */
                        error = -ENOENT;
                        break;
                default:
                        error = -EACCES;
                        break;
        }
out:
        unlock_kernel();
        return error;
}

static int ncp_unlink(struct inode *dir, struct dentry *dentry)
{
        struct inode *inode = dentry->d_inode;
        struct ncp_server *server;
        int error;

        lock_kernel();
        server = NCP_SERVER(dir);
        DPRINTK("ncp_unlink: unlinking %s/%s\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);
        
        error = -EIO;
        if (!ncp_conn_valid(server))
                goto out;

        /*
         * Check whether to close the file ...
         */
        if (inode) {
                PPRINTK("ncp_unlink: closing file\n");
                ncp_make_closed(inode);
        }

        error = ncp_del_file_or_subdir2(server, dentry);
#ifdef CONFIG_NCPFS_STRONG
        /* 9C is Invalid path.. It should be 8F, 90 - read only, but
           it is not :-( */
        if ((error == 0x9C || error == 0x90) && server->m.flags & NCP_MOUNT_STRONG) { /* R/O */
                error = ncp_force_unlink(dir, dentry);
        }
#endif
        switch (error) {
                case 0x00:
                        DPRINTK("ncp: removed %s/%s\n",
                                dentry->d_parent->d_name.name, dentry->d_name.name);
                        break;
                case 0x85:
                case 0x8A:
                        error = -EACCES;
                        break;
                case 0x8D:      /* some files in use */
                case 0x8E:      /* all files in use */
                        error = -EBUSY;
                        break;
                case 0x8F:      /* some read only */
                case 0x90:      /* all read only */
                case 0x9C:      /* !!! returned when in-use or read-only by NW4 */
                        error = -EPERM;
                        break;
                case 0xFF:
                        error = -ENOENT;
                        break;
                default:
                        error = -EACCES;
                        break;
        }
                
out:
        unlock_kernel();
        return error;
}

static int ncp_rename(struct inode *old_dir, struct dentry *old_dentry,
                      struct inode *new_dir, struct dentry *new_dentry)
{
        struct ncp_server *server = NCP_SERVER(old_dir);
        int error;
        int old_len, new_len;
        __u8 __old_name[NCP_MAXPATHLEN + 1], __new_name[NCP_MAXPATHLEN + 1];

        DPRINTK("ncp_rename: %s/%s to %s/%s\n",
                old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
                new_dentry->d_parent->d_name.name, new_dentry->d_name.name);

        error = -EIO;
        lock_kernel();
        if (!ncp_conn_valid(server))
                goto out;

        ncp_age_dentry(server, old_dentry);
        ncp_age_dentry(server, new_dentry);

        old_len = sizeof(__old_name);
        error = ncp_io2vol(server, __old_name, &old_len,
                           old_dentry->d_name.name, old_dentry->d_name.len,
                           !ncp_preserve_case(old_dir));
        if (error)
                goto out;

        new_len = sizeof(__new_name);
        error = ncp_io2vol(server, __new_name, &new_len,
                           new_dentry->d_name.name, new_dentry->d_name.len,
                           !ncp_preserve_case(new_dir));
        if (error)
                goto out;

        error = ncp_ren_or_mov_file_or_subdir(server, old_dir, __old_name,
                                                      new_dir, __new_name);
#ifdef CONFIG_NCPFS_STRONG
        if ((error == 0x90 || error == 0x8B || error == -EACCES) &&
                        server->m.flags & NCP_MOUNT_STRONG) {   /* RO */
                error = ncp_force_rename(old_dir, old_dentry, __old_name,
                                         new_dir, new_dentry, __new_name);
        }
#endif
        switch (error) {
                case 0x00:
                        DPRINTK("ncp renamed %s -> %s.\n",
                                old_dentry->d_name.name,new_dentry->d_name.name);
                        break;
                case 0x9E:
                        error = -ENAMETOOLONG;
                        break;
                case 0xFF:
                        error = -ENOENT;
                        break;
                default:
                        error = -EACCES;
                        break;
        }
out:
        unlock_kernel();
        return error;
}

static int ncp_mknod(struct inode * dir, struct dentry *dentry,
                     int mode, dev_t rdev)
{
        if (!new_valid_dev(rdev))
                return -EINVAL;
        if (ncp_is_nfs_extras(NCP_SERVER(dir), NCP_FINFO(dir)->volNumber)) {
                DPRINTK(KERN_DEBUG "ncp_mknod: mode = 0%o\n", mode);
                return ncp_create_new(dir, dentry, mode, rdev, 0);
        }
        return -EPERM; /* Strange, but true */
}

/* The following routines are taken directly from msdos-fs */

/* Linear day numbers of the respective 1sts in non-leap years. */

static int day_n[] =
{0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0, 0};
/* Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec */


extern struct timezone sys_tz;

static int utc2local(int time)
{
        return time - sys_tz.tz_minuteswest * 60;
}

static int local2utc(int time)
{
        return time + sys_tz.tz_minuteswest * 60;
}

/* Convert a MS-DOS time/date pair to a UNIX date (seconds since 1 1 70). */
int
ncp_date_dos2unix(__le16 t, __le16 d)
{
        unsigned short time = le16_to_cpu(t), date = le16_to_cpu(d);
        int month, year, secs;

        /* first subtract and mask after that... Otherwise, if
           date == 0, bad things happen */
        month = ((date >> 5) - 1) & 15;
        year = date >> 9;
        secs = (time & 31) * 2 + 60 * ((time >> 5) & 63) + (time >> 11) * 3600 +
                86400 * ((date & 31) - 1 + day_n[month] + (year / 4) + 
                year * 365 - ((year & 3) == 0 && month < 2 ? 1 : 0) + 3653);
        /* days since 1.1.70 plus 80's leap day */
        return local2utc(secs);
}


/* Convert linear UNIX date to a MS-DOS time/date pair. */
void
ncp_date_unix2dos(int unix_date, __le16 *time, __le16 *date)
{
        int day, year, nl_day, month;

        unix_date = utc2local(unix_date);
        *time = cpu_to_le16(
                (unix_date % 60) / 2 + (((unix_date / 60) % 60) << 5) +
                (((unix_date / 3600) % 24) << 11));
        day = unix_date / 86400 - 3652;
        year = day / 365;
        if ((year + 3) / 4 + 365 * year > day)
                year--;
        day -= (year + 3) / 4 + 365 * year;
        if (day == 59 && !(year & 3)) {
                nl_day = day;
                month = 2;
        } else {
                nl_day = (year & 3) || day <= 59 ? day : day - 1;
                for (month = 0; month < 12; month++)
                        if (day_n[month] > nl_day)
                                break;
        }
        *date = cpu_to_le16(nl_day - day_n[month - 1] + 1 + (month << 5) + (year << 9));
}