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/*
* dir.c
*
* Copyright (C) 1995, 1996 by Paal-Kr. Engstad and Volker Lendecke
* Copyright (C) 1997 by Volker Lendecke
*
* Please add a note about your changes to smbfs in the ChangeLog file.
*/
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/smp_lock.h>
#include <linux/ctype.h>
#include <linux/smb_fs.h>
#include <linux/smb_mount.h>
#include <linux/smbno.h>
#include "smb_debug.h"
#include "proto.h"
static int smb_readdir(struct file *, void *, filldir_t);
static int smb_dir_open(struct inode *, struct file *);
static struct dentry *smb_lookup(struct inode *, struct dentry *);
static int smb_create(struct inode *, struct dentry *, int);
static int smb_mkdir(struct inode *, struct dentry *, int);
static int smb_rmdir(struct inode *, struct dentry *);
static int smb_unlink(struct inode *, struct dentry *);
static int smb_rename(struct inode *, struct dentry *,
struct inode *, struct dentry *);
struct file_operations smb_dir_operations =
{
read: generic_read_dir,
readdir: smb_readdir,
ioctl: smb_ioctl,
open: smb_dir_open,
};
struct inode_operations smb_dir_inode_operations =
{
create: smb_create,
lookup: smb_lookup,
unlink: smb_unlink,
mkdir: smb_mkdir,
rmdir: smb_rmdir,
rename: smb_rename,
revalidate: smb_revalidate_inode,
setattr: smb_notify_change,
};
/*
* Read a directory, using filldir to fill the dirent memory.
* smb_proc_readdir does the actual reading from the smb server.
*
* The cache code is almost directly taken from ncpfs
*/
static int
smb_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct dentry *dentry = filp->f_dentry;
struct inode *dir = dentry->d_inode;
struct smb_sb_info *server = server_from_dentry(dentry);
union smb_dir_cache *cache = NULL;
struct smb_cache_control ctl;
struct page *page = NULL;
int result;
ctl.page = NULL;
ctl.cache = NULL;
VERBOSE("reading %s/%s, f_pos=%d\n",
DENTRY_PATH(dentry), (int) filp->f_pos);
result = 0;
switch ((unsigned int) filp->f_pos) {
case 0:
if (filldir(dirent, ".", 1, 0, dir->i_ino, DT_DIR) < 0)
goto out;
filp->f_pos = 1;
/* fallthrough */
case 1:
if (filldir(dirent, "..", 2, 1,
dentry->d_parent->d_inode->i_ino, DT_DIR) < 0)
goto out;
filp->f_pos = 2;
}
/*
* Make sure our inode is up-to-date.
*/
result = smb_revalidate_inode(dentry);
if (result)
goto out;
page = grab_cache_page(&dir->i_data, 0);
if (!page)
goto read_really;
ctl.cache = cache = kmap(page);
ctl.head = cache->head;
if (!Page_Uptodate(page) || !ctl.head.eof) {
VERBOSE("%s/%s, page uptodate=%d, eof=%d\n",
DENTRY_PATH(dentry), Page_Uptodate(page),ctl.head.eof);
goto init_cache;
}
if (filp->f_pos == 2) {
if (jiffies - ctl.head.time >= SMB_MAX_AGE(server))
goto init_cache;
/*
* N.B. ncpfs checks mtime of dentry too here, we don't.
* 1. common smb servers do not update mtime on dir changes
* 2. it requires an extra smb request
* (revalidate has the same timeout as ctl.head.time)
*
* Instead smbfs invalidates its own cache on local changes
* and remote changes are not seen until timeout.
*/
}
if (filp->f_pos > ctl.head.end)
goto finished;
ctl.fpos = filp->f_pos + (SMB_DIRCACHE_START - 2);
ctl.ofs = ctl.fpos / SMB_DIRCACHE_SIZE;
ctl.idx = ctl.fpos % SMB_DIRCACHE_SIZE;
for (;;) {
if (ctl.ofs != 0) {
ctl.page = find_lock_page(&dir->i_data, ctl.ofs);
if (!ctl.page)
goto invalid_cache;
ctl.cache = kmap(ctl.page);
if (!Page_Uptodate(ctl.page))
goto invalid_cache;
}
while (ctl.idx < SMB_DIRCACHE_SIZE) {
struct dentry *dent;
int res;
dent = smb_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);
UnlockPage(ctl.page);
page_cache_release(ctl.page);
ctl.page = NULL;
}
ctl.idx = 0;
ctl.ofs += 1;
}
invalid_cache:
if (ctl.page) {
kunmap(ctl.page);
UnlockPage(ctl.page);
page_cache_release(ctl.page);
ctl.page = NULL;
}
ctl.cache = cache;
init_cache:
smb_invalidate_dircache_entries(dentry);
ctl.head.time = jiffies;
ctl.head.eof = 0;
ctl.fpos = 2;
ctl.ofs = 0;
ctl.idx = SMB_DIRCACHE_START;
ctl.filled = 0;
ctl.valid = 1;
read_really:
result = smb_proc_readdir(filp, dirent, filldir, &ctl);
if (ctl.idx == -1)
goto invalid_cache; /* retry */
ctl.head.end = ctl.fpos - 1;
ctl.head.eof = ctl.valid;
finished:
if (page) {
cache->head = ctl.head;
kunmap(page);
SetPageUptodate(page);
UnlockPage(page);
page_cache_release(page);
}
if (ctl.page) {
kunmap(ctl.page);
SetPageUptodate(ctl.page);
UnlockPage(ctl.page);
page_cache_release(ctl.page);
}
out:
return result;
}
static int
smb_dir_open(struct inode *dir, struct file *file)
{
struct dentry *dentry = file->f_dentry;
struct smb_sb_info *server;
int error = 0;
VERBOSE("(%s/%s)\n", dentry->d_parent->d_name.name,
file->f_dentry->d_name.name);
/*
* Directory timestamps in the core protocol aren't updated
* when a file is added, so we give them a very short TTL.
*/
lock_kernel();
server = server_from_dentry(dentry);
if (server->opt.protocol < SMB_PROTOCOL_LANMAN2) {
unsigned long age = jiffies - dir->u.smbfs_i.oldmtime;
if (age > 2*HZ)
smb_invalid_dir_cache(dir);
}
/*
* Note: in order to allow the smbmount process to open the
* mount point, we only revalidate if the connection is valid or
* if the process is trying to access something other than the root.
*/
if (server->state == CONN_VALID || !IS_ROOT(dentry))
error = smb_revalidate_inode(dentry);
unlock_kernel();
return error;
}
/*
* Dentry operations routines
*/
static int smb_lookup_validate(struct dentry *, int);
static int smb_hash_dentry(struct dentry *, struct qstr *);
static int smb_compare_dentry(struct dentry *, struct qstr *, struct qstr *);
static int smb_delete_dentry(struct dentry *);
static struct dentry_operations smbfs_dentry_operations =
{
d_revalidate: smb_lookup_validate,
d_hash: smb_hash_dentry,
d_compare: smb_compare_dentry,
d_delete: smb_delete_dentry,
};
static struct dentry_operations smbfs_dentry_operations_case =
{
d_revalidate: smb_lookup_validate,
d_delete: smb_delete_dentry,
};
/*
* This is the callback when the dcache has a lookup hit.
*/
static int
smb_lookup_validate(struct dentry * dentry, int flags)
{
struct smb_sb_info *server = server_from_dentry(dentry);
struct inode * inode = dentry->d_inode;
unsigned long age = jiffies - dentry->d_time;
int valid;
/*
* The default validation is based on dentry age:
* we believe in dentries for a few seconds. (But each
* successful server lookup renews the timestamp.)
*/
valid = (age <= SMB_MAX_AGE(server));
#ifdef SMBFS_DEBUG_VERBOSE
if (!valid)
VERBOSE("%s/%s not valid, age=%lu\n",
DENTRY_PATH(dentry), age);
#endif
if (inode) {
lock_kernel();
if (is_bad_inode(inode)) {
PARANOIA("%s/%s has dud inode\n", DENTRY_PATH(dentry));
valid = 0;
} else if (!valid)
valid = (smb_revalidate_inode(dentry) == 0);
unlock_kernel();
} else {
/*
* What should we do for negative dentries?
*/
}
return valid;
}
static int
smb_hash_dentry(struct dentry *dir, struct qstr *this)
{
unsigned long hash;
int i;
hash = init_name_hash();
for (i=0; i < this->len ; i++)
hash = partial_name_hash(tolower(this->name[i]), hash);
this->hash = end_name_hash(hash);
return 0;
}
static int
smb_compare_dentry(struct dentry *dir, struct qstr *a, struct qstr *b)
{
int i, result = 1;
if (a->len != b->len)
goto out;
for (i=0; i < a->len; i++) {
if (tolower(a->name[i]) != tolower(b->name[i]))
goto out;
}
result = 0;
out:
return result;
}
/*
* This is the callback from dput() when d_count is going to 0.
* We use this to unhash dentries with bad inodes.
*/
static int
smb_delete_dentry(struct dentry * dentry)
{
if (dentry->d_inode) {
if (is_bad_inode(dentry->d_inode)) {
PARANOIA("bad inode, unhashing %s/%s\n",
DENTRY_PATH(dentry));
return 1;
}
} else {
/* N.B. Unhash negative dentries? */
}
return 0;
}
/*
* Initialize a new dentry
*/
void
smb_new_dentry(struct dentry *dentry)
{
struct smb_sb_info *server = server_from_dentry(dentry);
if (server->mnt->flags & SMB_MOUNT_CASE)
dentry->d_op = &smbfs_dentry_operations_case;
else
dentry->d_op = &smbfs_dentry_operations;
dentry->d_time = jiffies;
}
/*
* Whenever a lookup succeeds, we know the parent directories
* are all valid, so we want to update the dentry timestamps.
* N.B. Move this to dcache?
*/
void
smb_renew_times(struct dentry * dentry)
{
for (;;) {
dentry->d_time = jiffies;
if (IS_ROOT(dentry))
break;
dentry = dentry->d_parent;
}
}
static struct dentry *
smb_lookup(struct inode *dir, struct dentry *dentry)
{
struct smb_fattr finfo;
struct inode *inode;
int error;
struct smb_sb_info *server;
error = -ENAMETOOLONG;
if (dentry->d_name.len > SMB_MAXNAMELEN)
goto out;
error = smb_proc_getattr(dentry, &finfo);
#ifdef SMBFS_PARANOIA
if (error && error != -ENOENT)
PARANOIA("find %s/%s failed, error=%d\n",
DENTRY_PATH(dentry), error);
#endif
inode = NULL;
if (error == -ENOENT)
goto add_entry;
if (!error) {
error = -EACCES;
finfo.f_ino = iunique(dentry->d_sb, 2);
inode = smb_iget(dir->i_sb, &finfo);
if (inode) {
add_entry:
server = server_from_dentry(dentry);
if (server->mnt->flags & SMB_MOUNT_CASE)
dentry->d_op = &smbfs_dentry_operations_case;
else
dentry->d_op = &smbfs_dentry_operations;
d_add(dentry, inode);
smb_renew_times(dentry);
error = 0;
}
}
out:
return ERR_PTR(error);
}
/*
* This code is common to all routines creating a new inode.
*/
static int
smb_instantiate(struct dentry *dentry, __u16 fileid, int have_id)
{
struct smb_sb_info *server = server_from_dentry(dentry);
struct inode *inode;
int error;
struct smb_fattr fattr;
VERBOSE("file %s/%s, fileid=%u\n", DENTRY_PATH(dentry), fileid);
error = smb_proc_getattr(dentry, &fattr);
if (error)
goto out_close;
smb_renew_times(dentry);
fattr.f_ino = iunique(dentry->d_sb, 2);
inode = smb_iget(dentry->d_sb, &fattr);
if (!inode)
goto out_no_inode;
if (have_id) {
inode->u.smbfs_i.fileid = fileid;
inode->u.smbfs_i.access = SMB_O_RDWR;
inode->u.smbfs_i.open = server->generation;
}
d_instantiate(dentry, inode);
out:
return error;
out_no_inode:
error = -EACCES;
out_close:
if (have_id) {
PARANOIA("%s/%s failed, error=%d, closing %u\n",
DENTRY_PATH(dentry), error, fileid);
smb_close_fileid(dentry, fileid);
}
goto out;
}
/* N.B. How should the mode argument be used? */
static int
smb_create(struct inode *dir, struct dentry *dentry, int mode)
{
__u16 fileid;
int error;
VERBOSE("creating %s/%s, mode=%d\n", DENTRY_PATH(dentry), mode);
smb_invalid_dir_cache(dir);
error = smb_proc_create(dentry, 0, CURRENT_TIME, &fileid);
if (!error) {
error = smb_instantiate(dentry, fileid, 1);
} else {
PARANOIA("%s/%s failed, error=%d\n",
DENTRY_PATH(dentry), error);
}
return error;
}
/* N.B. How should the mode argument be used? */
static int
smb_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
int error;
smb_invalid_dir_cache(dir);
error = smb_proc_mkdir(dentry);
if (!error) {
error = smb_instantiate(dentry, 0, 0);
}
return error;
}
static int
smb_rmdir(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
int error;
/*
* Close the directory if it's open.
*/
smb_close(inode);
/*
* Check that nobody else is using the directory..
*/
error = -EBUSY;
if (!d_unhashed(dentry))
goto out;
smb_invalid_dir_cache(dir);
error = smb_proc_rmdir(dentry);
out:
return error;
}
static int
smb_unlink(struct inode *dir, struct dentry *dentry)
{
int error;
/*
* Close the file if it's open.
*/
smb_close(dentry->d_inode);
smb_invalid_dir_cache(dir);
error = smb_proc_unlink(dentry);
if (!error)
smb_renew_times(dentry);
return error;
}
static int
smb_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
int error;
/*
* Close any open files, and check whether to delete the
* target before attempting the rename.
*/
if (old_dentry->d_inode)
smb_close(old_dentry->d_inode);
if (new_dentry->d_inode) {
smb_close(new_dentry->d_inode);
error = smb_proc_unlink(new_dentry);
if (error) {
VERBOSE("unlink %s/%s, error=%d\n",
DENTRY_PATH(new_dentry), error);
goto out;
}
/* FIXME */
d_delete(new_dentry);
}
smb_invalid_dir_cache(old_dir);
smb_invalid_dir_cache(new_dir);
error = smb_proc_mv(old_dentry, new_dentry);
if (!error) {
smb_renew_times(old_dentry);
smb_renew_times(new_dentry);
}
out:
return error;
}
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