/**
* nilfs_try_to_shrink_tree() - try to shrink dentries of a checkpoint
* @root_dentry: root dentry of the tree to be shrunk
*
* This function returns true if the tree was in-use.
*/
static int nilfs_try_to_shrink_tree(struct dentry *root_dentry)
{
if (have_submounts(root_dentry))
return true;
shrink_dcache_parent(root_dentry);
return nilfs_tree_was_touched(root_dentry);
}
/*
* This is called every time the dcache has a lookup hit,
* and we should check whether we can really trust that
* lookup.
*
* NOTE! The hit can be a negative hit too, don't assume
* we have an inode!
*
* If the parent directory is seen to have changed, we throw out the
* cached dentry and do a new lookup.
*/
static int nfs_lookup_revalidate(struct dentry * dentry, int flags)
{
struct inode *dir;
struct inode *inode;
int error;
struct nfs_fh fhandle;
struct nfs_fattr fattr;
lock_kernel();
dir = dentry->d_parent->d_inode;
inode = dentry->d_inode;
if (!inode) {
if (nfs_neg_need_reval(dir, dentry))
goto out_bad;
goto out_valid;
}
if (is_bad_inode(inode)) {
dfprintk(VFS, "nfs_lookup_validate: %s/%s has dud inode\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
goto out_bad;
}
/* Force a full look up iff the parent directory has changed */
if (nfs_check_verifier(dir, dentry)) {
if (nfs_lookup_verify_inode(inode, flags))
goto out_bad;
goto out_valid;
}
if (NFS_STALE(inode))
goto out_bad;
error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, &fhandle, &fattr);
if (error)
goto out_bad;
if (memcmp(NFS_FH(inode), &fhandle, sizeof(struct nfs_fh))!= 0)
goto out_bad;
if ((error = nfs_refresh_inode(inode, &fattr)) != 0)
goto out_bad;
nfs_renew_times(dentry);
out_valid:
unlock_kernel();
return 1;
out_bad:
NFS_CACHEINV(dir);
if (inode && S_ISDIR(inode->i_mode)) {
/* Purge readdir caches. */
nfs_zap_caches(inode);
/* If we have submounts, don't unhash ! */
if (have_submounts(dentry))
goto out_valid;
shrink_dcache_parent(dentry);
}
d_drop(dentry);
unlock_kernel();
return 0;
}
/*
* Check if the given path is a mountpoint.
*
* If we are supplied with the file descriptor of an autofs
* mount we're looking for a specific mount. In this case
* the path is considered a mountpoint if it is itself a
* mountpoint or contains a mount, such as a multi-mount
* without a root mount. In this case we return 1 if the
* path is a mount point and the super magic of the covering
* mount if there is one or 0 if it isn't a mountpoint.
*
* If we aren't supplied with a file descriptor then we
* lookup the nameidata of the path and check if it is the
* root of a mount. If a type is given we are looking for
* a particular autofs mount and if we don't find a match
* we return fail. If the located nameidata path is the
* root of a mount we return 1 along with the super magic
* of the mount or 0 otherwise.
*
* In both cases the the device number (as returned by
* new_encode_dev()) is also returned.
*/
static int autofs_dev_ioctl_ismountpoint(struct file *fp,
struct autofs_sb_info *sbi,
struct autofs_dev_ioctl *param)
{
struct path path;
const char *name;
unsigned int type;
unsigned int devid, magic;
int err = -ENOENT;
if (param->size <= sizeof(*param)) {
err = -EINVAL;
goto out;
}
name = param->path;
type = param->ismountpoint.in.type;
param->ismountpoint.out.devid = devid = 0;
param->ismountpoint.out.magic = magic = 0;
if (!fp || param->ioctlfd == -1) {
if (autofs_type_any(type))
err = kern_path(name, LOOKUP_FOLLOW, &path);
else
err = find_autofs_mount(name, &path, test_by_type, &type);
if (err)
goto out;
devid = new_encode_dev(path.mnt->mnt_sb->s_dev);
err = 0;
if (path.dentry->d_inode &&
path.mnt->mnt_root == path.dentry) {
err = 1;
magic = path.dentry->d_inode->i_sb->s_magic;
}
} else {
dev_t dev = sbi->sb->s_dev;
err = find_autofs_mount(name, &path, test_by_dev, &dev);
if (err)
goto out;
devid = new_encode_dev(dev);
err = have_submounts(path.dentry);
if (path.mnt->mnt_mountpoint != path.mnt->mnt_root) {
if (follow_down(&path))
magic = path.mnt->mnt_sb->s_magic;
}
}
param->ismountpoint.out.devid = devid;
param->ismountpoint.out.magic = magic;
path_put(&path);
out:
return err;
}
int have_submounts_init(void)
{
struct dentry *dentry_parent = current->fs->pwd.dentry->d_parent;
int data = have_submounts(dentry_parent);
if(data==0)
printk("<0> Current dentry has not munt.\n");
else
printk("<0> Current dentry has munt.\n");
return 0;
}
static int sysfs_dentry_revalidate(struct dentry *dentry, struct nameidata *nd)
{
struct sysfs_dirent *sd = dentry->d_fsdata;
int is_dir;
mutex_lock(&sysfs_mutex);
/* The sysfs dirent has been deleted */
if (sd->s_flags & SYSFS_FLAG_REMOVED)
goto out_bad;
/* The sysfs dirent has been moved? */
if (dentry->d_parent->d_fsdata != sd->s_parent)
goto out_bad;
/* The sysfs dirent has been renamed */
if (strcmp(dentry->d_name.name, sd->s_name) != 0)
goto out_bad;
mutex_unlock(&sysfs_mutex);
out_valid:
return 1;
out_bad:
/* Remove the dentry from the dcache hashes.
* If this is a deleted dentry we use d_drop instead of d_delete
* so sysfs doesn't need to cope with negative dentries.
*
* If this is a dentry that has simply been renamed we
* use d_drop to remove it from the dcache lookup on its
* old parent. If this dentry persists later when a lookup
* is performed at its new name the dentry will be readded
* to the dcache hashes.
*/
is_dir = (sysfs_type(sd) == SYSFS_DIR);
mutex_unlock(&sysfs_mutex);
if (is_dir) {
/* If we have submounts we must allow the vfs caches
* to lie about the state of the filesystem to prevent
* leaks and other nasty things.
*/
if (have_submounts(dentry))
goto out_valid;
shrink_dcache_parent(dentry);
}
d_drop(dentry);
return 0;
}
/*
* check that a dentry lookup hit has found a valid entry
* - NOTE! the hit can be a negative hit too, so we can't assume we have an
* inode
*/
static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
{
struct afs_vnode *vnode, *dir;
struct afs_fid uninitialized_var(fid);
struct dentry *parent;
struct key *key;
void *dir_version;
int ret;
if (nd->flags & LOOKUP_RCU)
return -ECHILD;
vnode = AFS_FS_I(dentry->d_inode);
if (dentry->d_inode)
_enter("{v={%x:%u} n=%s fl=%lx},",
vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name,
vnode->flags);
else
_enter("{neg n=%s}", dentry->d_name.name);
key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
if (IS_ERR(key))
key = NULL;
/* lock down the parent dentry so we can peer at it */
parent = dget_parent(dentry);
if (!parent->d_inode)
goto out_bad;
dir = AFS_FS_I(parent->d_inode);
/* validate the parent directory */
if (test_bit(AFS_VNODE_MODIFIED, &dir->flags))
afs_validate(dir, key);
if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
_debug("%s: parent dir deleted", dentry->d_name.name);
goto out_bad;
}
dir_version = (void *) (unsigned long) dir->status.data_version;
if (dentry->d_fsdata == dir_version)
goto out_valid; /* the dir contents are unchanged */
_debug("dir modified");
/* search the directory for this vnode */
ret = afs_do_lookup(&dir->vfs_inode, dentry, &fid, key);
switch (ret) {
case 0:
/* the filename maps to something */
if (!dentry->d_inode)
goto out_bad;
if (is_bad_inode(dentry->d_inode)) {
printk("kAFS: afs_d_revalidate: %s/%s has bad inode\n",
parent->d_name.name, dentry->d_name.name);
goto out_bad;
}
/* if the vnode ID has changed, then the dirent points to a
* different file */
if (fid.vnode != vnode->fid.vnode) {
_debug("%s: dirent changed [%u != %u]",
dentry->d_name.name, fid.vnode,
vnode->fid.vnode);
goto not_found;
}
/* if the vnode ID uniqifier has changed, then the file has
* been deleted and replaced, and the original vnode ID has
* been reused */
if (fid.unique != vnode->fid.unique) {
_debug("%s: file deleted (uq %u -> %u I:%u)",
dentry->d_name.name, fid.unique,
vnode->fid.unique,
dentry->d_inode->i_generation);
spin_lock(&vnode->lock);
set_bit(AFS_VNODE_DELETED, &vnode->flags);
spin_unlock(&vnode->lock);
goto not_found;
}
goto out_valid;
case -ENOENT:
/* the filename is unknown */
_debug("%s: dirent not found", dentry->d_name.name);
if (dentry->d_inode)
goto not_found;
goto out_valid;
default:
_debug("failed to iterate dir %s: %d",
parent->d_name.name, ret);
goto out_bad;
}
out_valid:
dentry->d_fsdata = dir_version;
out_skip:
dput(parent);
key_put(key);
_leave(" = 1 [valid]");
return 1;
/* the dirent, if it exists, now points to a different vnode */
not_found:
spin_lock(&dentry->d_lock);
dentry->d_flags |= DCACHE_NFSFS_RENAMED;
spin_unlock(&dentry->d_lock);
out_bad:
if (dentry->d_inode) {
/* don't unhash if we have submounts */
if (have_submounts(dentry))
goto out_skip;
}
_debug("dropping dentry %s/%s",
parent->d_name.name, dentry->d_name.name);
shrink_dcache_parent(dentry);
d_drop(dentry);
dput(parent);
key_put(key);
_leave(" = 0 [bad]");
return 0;
}
static int gfs2_drevalidate(struct dentry *dentry, struct nameidata *nd)
{
struct dentry *parent;
struct gfs2_sbd *sdp;
struct gfs2_inode *dip;
struct inode *inode;
struct gfs2_holder d_gh;
struct gfs2_inode *ip = NULL;
int error;
int had_lock = 0;
if (nd && nd->flags & LOOKUP_RCU)
return -ECHILD;
parent = dget_parent(dentry);
sdp = GFS2_SB(parent->d_inode);
dip = GFS2_I(parent->d_inode);
inode = dentry->d_inode;
if (inode) {
if (is_bad_inode(inode))
goto invalid;
ip = GFS2_I(inode);
}
if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
goto valid;
had_lock = (gfs2_glock_is_locked_by_me(dip->i_gl) != NULL);
if (!had_lock) {
error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
if (error)
goto fail;
}
error = gfs2_dir_check(parent->d_inode, &dentry->d_name, ip);
switch (error) {
case 0:
if (!inode)
goto invalid_gunlock;
break;
case -ENOENT:
if (!inode)
goto valid_gunlock;
goto invalid_gunlock;
default:
goto fail_gunlock;
}
valid_gunlock:
if (!had_lock)
gfs2_glock_dq_uninit(&d_gh);
valid:
dput(parent);
return 1;
invalid_gunlock:
if (!had_lock)
gfs2_glock_dq_uninit(&d_gh);
invalid:
if (inode && S_ISDIR(inode->i_mode)) {
if (have_submounts(dentry))
goto valid;
shrink_dcache_parent(dentry);
}
d_drop(dentry);
dput(parent);
return 0;
fail_gunlock:
gfs2_glock_dq_uninit(&d_gh);
fail:
dput(parent);
return 0;
}
static int gfs2_drevalidate(struct dentry *dentry, struct nameidata *nd)
{
struct dentry *parent = dget_parent(dentry);
struct gfs2_sbd *sdp = GFS2_SB(parent->d_inode);
struct gfs2_inode *dip = GFS2_I(parent->d_inode);
struct inode *inode = dentry->d_inode;
struct gfs2_holder d_gh;
struct gfs2_inode *ip;
struct gfs2_inum_host inum;
unsigned int type;
int error;
int had_lock=0;
if (inode && is_bad_inode(inode))
goto invalid;
if (sdp->sd_args.ar_localcaching)
goto valid;
had_lock = gfs2_glock_is_locked_by_me(dip->i_gl);
if (!had_lock) {
error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
if (error)
goto fail;
}
error = gfs2_dir_search(parent->d_inode, &dentry->d_name, &inum, &type);
switch (error) {
case 0:
if (!inode)
goto invalid_gunlock;
break;
case -ENOENT:
if (!inode)
goto valid_gunlock;
goto invalid_gunlock;
default:
goto fail_gunlock;
}
ip = GFS2_I(inode);
if (!gfs2_inum_equal(&ip->i_num, &inum))
goto invalid_gunlock;
if (IF2DT(ip->i_inode.i_mode) != type) {
gfs2_consist_inode(dip);
goto fail_gunlock;
}
valid_gunlock:
if (!had_lock)
gfs2_glock_dq_uninit(&d_gh);
valid:
dput(parent);
return 1;
invalid_gunlock:
if (!had_lock)
gfs2_glock_dq_uninit(&d_gh);
invalid:
if (inode && S_ISDIR(inode->i_mode)) {
if (have_submounts(dentry))
goto valid;
shrink_dcache_parent(dentry);
}
d_drop(dentry);
dput(parent);
return 0;
fail_gunlock:
gfs2_glock_dq_uninit(&d_gh);
fail:
dput(parent);
return 0;
}
/*
* check that a dentry lookup hit has found a valid entry
* - NOTE! the hit can be a negative hit too, so we can't assume we have an
* inode
* (derived from nfs_lookup_revalidate)
*/
static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
{
struct afs_dir_lookup_cookie cookie;
struct dentry *parent;
struct inode *inode, *dir;
unsigned fpos;
int ret;
_enter("{sb=%p n=%s},", dentry->d_sb, dentry->d_name.name);
/* lock down the parent dentry so we can peer at it */
parent = dget_parent(dentry->d_parent);
dir = parent->d_inode;
inode = dentry->d_inode;
/* handle a negative dentry */
if (!inode)
goto out_bad;
/* handle a bad inode */
if (is_bad_inode(inode)) {
printk("kAFS: afs_d_revalidate: %s/%s has bad inode\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
goto out_bad;
}
/* force a full look up if the parent directory changed since last the
* server was consulted
* - otherwise this inode must still exist, even if the inode details
* themselves have changed
*/
if (AFS_FS_I(dir)->flags & AFS_VNODE_CHANGED)
afs_vnode_fetch_status(AFS_FS_I(dir));
if (AFS_FS_I(dir)->flags & AFS_VNODE_DELETED) {
_debug("%s: parent dir deleted", dentry->d_name.name);
goto out_bad;
}
if (AFS_FS_I(inode)->flags & AFS_VNODE_DELETED) {
_debug("%s: file already deleted", dentry->d_name.name);
goto out_bad;
}
if ((unsigned long) dentry->d_fsdata !=
(unsigned long) AFS_FS_I(dir)->status.version) {
_debug("%s: parent changed %lu -> %u",
dentry->d_name.name,
(unsigned long) dentry->d_fsdata,
(unsigned) AFS_FS_I(dir)->status.version);
/* search the directory for this vnode */
cookie.name = dentry->d_name.name;
cookie.nlen = dentry->d_name.len;
cookie.fid.vid = AFS_FS_I(inode)->volume->vid;
cookie.found = 0;
fpos = 0;
ret = afs_dir_iterate(dir, &fpos, &cookie,
afs_dir_lookup_filldir);
if (ret < 0) {
_debug("failed to iterate dir %s: %d",
parent->d_name.name, ret);
goto out_bad;
}
if (!cookie.found) {
_debug("%s: dirent not found", dentry->d_name.name);
goto not_found;
}
/* if the vnode ID has changed, then the dirent points to a
* different file */
if (cookie.fid.vnode != AFS_FS_I(inode)->fid.vnode) {
_debug("%s: dirent changed", dentry->d_name.name);
goto not_found;
}
/* if the vnode ID uniqifier has changed, then the file has
* been deleted */
if (cookie.fid.unique != AFS_FS_I(inode)->fid.unique) {
_debug("%s: file deleted (uq %u -> %u I:%lu)",
dentry->d_name.name,
cookie.fid.unique,
AFS_FS_I(inode)->fid.unique,
inode->i_version);
spin_lock(&AFS_FS_I(inode)->lock);
AFS_FS_I(inode)->flags |= AFS_VNODE_DELETED;
spin_unlock(&AFS_FS_I(inode)->lock);
invalidate_remote_inode(inode);
goto out_bad;
}
dentry->d_fsdata =
(void *) (unsigned long) AFS_FS_I(dir)->status.version;
}
out_valid:
dput(parent);
_leave(" = 1 [valid]");
return 1;
/* the dirent, if it exists, now points to a different vnode */
not_found:
spin_lock(&dentry->d_lock);
dentry->d_flags |= DCACHE_NFSFS_RENAMED;
spin_unlock(&dentry->d_lock);
out_bad:
if (inode) {
/* don't unhash if we have submounts */
if (have_submounts(dentry))
goto out_valid;
}
shrink_dcache_parent(dentry);
_debug("dropping dentry %s/%s",
dentry->d_parent->d_name.name, dentry->d_name.name);
d_drop(dentry);
dput(parent);
_leave(" = 0 [bad]");
return 0;
} /* end afs_d_revalidate() */
/*
* Check if we have a valid request.
* Returns
* 1 if the request should continue.
* In this case we can return an autofs_wait_queue entry if one is
* found or NULL to idicate a new wait needs to be created.
* 0 or a negative errno if the request shouldn't continue.
*/
static int validate_request(struct autofs_wait_queue **wait,
struct autofs_sb_info *sbi,
struct qstr *qstr,
struct dentry*dentry, enum autofs_notify notify)
{
struct autofs_wait_queue *wq;
struct autofs_info *ino;
/* Wait in progress, continue; */
wq = autofs4_find_wait(sbi, qstr);
if (wq) {
*wait = wq;
return 1;
}
*wait = NULL;
/* If we don't yet have any info this is a new request */
ino = autofs4_dentry_ino(dentry);
if (!ino)
return 1;
/*
* If we've been asked to wait on an existing expire (NFY_NONE)
* but there is no wait in the queue ...
*/
if (notify == NFY_NONE) {
/*
* Either we've betean the pending expire to post it's
* wait or it finished while we waited on the mutex.
* So we need to wait till either, the wait appears
* or the expire finishes.
*/
while (ino->flags & AUTOFS_INF_EXPIRING) {
mutex_unlock(&sbi->wq_mutex);
schedule_timeout_interruptible(HZ/10);
if (mutex_lock_interruptible(&sbi->wq_mutex))
return -EINTR;
wq = autofs4_find_wait(sbi, qstr);
if (wq) {
*wait = wq;
return 1;
}
}
/*
* Not ideal but the status has already gone. Of the two
* cases where we wait on NFY_NONE neither depend on the
* return status of the wait.
*/
return 0;
}
/*
* If we've been asked to trigger a mount and the request
* completed while we waited on the mutex ...
*/
if (notify == NFY_MOUNT) {
/*
* If the dentry was successfully mounted while we slept
* on the wait queue mutex we can return success. If it
* isn't mounted (doesn't have submounts for the case of
* a multi-mount with no mount at it's base) we can
* continue on and create a new request.
*/
if (have_submounts(dentry))
return 0;
}
return 1;
}
/*
* Check whether the dentry is still valid
*
* If the entry validity timeout has expired and the dentry is
* positive, try to redo the lookup. If the lookup results in a
* different inode, then let the VFS invalidate the dentry and redo
* the lookup once more. If the lookup results in the same inode,
* then refresh the attributes, timeouts and mark the dentry valid.
*/
static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd)
{
struct inode *inode = entry->d_inode;
struct dentry *parent;
struct fuse_conn *fc;
int ret;
if (inode && is_bad_inode(inode))
goto invalid;
else if (time_before64(fuse_dentry_time(entry), get_jiffies_64()) ||
(nd->flags & LOOKUP_REVAL)) {
int err;
struct fuse_entry_out outarg;
struct fuse_req *req;
struct fuse_forget_link *forget;
u64 attr_version;
/* For negative dentries, always do a fresh lookup */
if (!inode)
goto invalid;
fc = get_fuse_conn(inode);
req = fuse_get_req_nopages(fc);
ret = PTR_ERR(req);
if (IS_ERR(req))
goto out;
forget = fuse_alloc_forget();
if (!forget) {
fuse_put_request(fc, req);
ret = -ENOMEM;
goto out;
}
attr_version = fuse_get_attr_version(fc);
parent = dget_parent(entry);
fuse_lookup_init(fc, req, get_node_id(parent->d_inode),
&entry->d_name, &outarg);
fuse_request_send(fc, req);
dput(parent);
err = req->out.h.error;
fuse_put_request(fc, req);
/* Zero nodeid is same as -ENOENT */
if (!err && !outarg.nodeid)
err = -ENOENT;
if (!err) {
struct fuse_inode *fi = get_fuse_inode(inode);
if (outarg.nodeid != get_node_id(inode)) {
fuse_queue_forget(fc, forget, outarg.nodeid, 1);
goto invalid;
}
spin_lock(&fc->lock);
fi->nlookup++;
spin_unlock(&fc->lock);
}
kfree(forget);
if (err || (outarg.attr.mode ^ inode->i_mode) & S_IFMT)
goto invalid;
fuse_change_attributes(inode, &outarg.attr,
entry_attr_timeout(&outarg),
attr_version);
fuse_change_entry_timeout(entry, &outarg);
} else if (inode) {
fc = get_fuse_conn(inode);
if (fc->readdirplus_auto) {
parent = dget_parent(entry);
fuse_advise_use_readdirplus(parent->d_inode);
dput(parent);
}
}
ret = 1;
out:
return ret;
invalid:
ret = 0;
if (inode) {
if (S_ISDIR(inode->i_mode)) {
if (have_submounts(entry)) {
ret = 1;
goto out;
}
shrink_dcache_parent(entry);
} else {
if (d_mountpoint(entry)) {
ret = 1;
goto out;
}
}
}
d_drop(entry);
goto out;
}
/*
* Check if the given path is a mountpoint.
*
* If we are supplied with the file descriptor of an autofs
* mount we're looking for a specific mount. In this case
* the path is considered a mountpoint if it is itself a
* mountpoint or contains a mount, such as a multi-mount
* without a root mount. In this case we return 1 if the
* path is a mount point and the super magic of the covering
* mount if there is one or 0 if it isn't a mountpoint.
*
* If we aren't supplied with a file descriptor then we
* lookup the nameidata of the path and check if it is the
* root of a mount. If a type is given we are looking for
* a particular autofs mount and if we don't find a match
* we return fail. If the located nameidata path is the
* root of a mount we return 1 along with the super magic
* of the mount or 0 otherwise.
*
* In both cases the the device number (as returned by
* new_encode_dev()) is also returned.
*/
static int autofs_dev_ioctl_ismountpoint(struct file *fp,
struct autofs_sb_info *sbi,
struct autofs_dev_ioctl *param)
{
struct nameidata nd;
const char *path;
unsigned int type;
int err = -ENOENT;
if (param->size <= sizeof(*param)) {
err = -EINVAL;
goto out;
}
path = param->path;
type = param->arg1;
param->arg1 = 0;
param->arg2 = 0;
if (!fp || param->ioctlfd == -1) {
if (type == AUTOFS_TYPE_ANY) {
struct super_block *sb;
err = path_lookup(path, LOOKUP_FOLLOW, &nd);
if (err)
goto out;
sb = nd.path.dentry->d_sb;
param->arg1 = new_encode_dev(sb->s_dev);
} else {
struct autofs_info *ino;
err = path_lookup(path, LOOKUP_PARENT, &nd);
if (err)
goto out;
err = autofs_dev_ioctl_find_sbi_type(&nd, type);
if (err)
goto out_release;
ino = autofs4_dentry_ino(nd.path.dentry);
param->arg1 = autofs4_get_dev(ino->sbi);
}
err = 0;
if (nd.path.dentry->d_inode &&
nd.path.mnt->mnt_root == nd.path.dentry) {
err = 1;
param->arg2 = nd.path.dentry->d_inode->i_sb->s_magic;
}
} else {
dev_t devid = new_encode_dev(sbi->sb->s_dev);
err = path_lookup(path, LOOKUP_PARENT, &nd);
if (err)
goto out;
err = autofs_dev_ioctl_find_super(&nd, devid);
if (err)
goto out_release;
param->arg1 = autofs4_get_dev(sbi);
err = have_submounts(nd.path.dentry);
if (nd.path.mnt->mnt_mountpoint != nd.path.mnt->mnt_root) {
if (follow_down(&nd.path.mnt, &nd.path.dentry)) {
struct inode *inode = nd.path.dentry->d_inode;
param->arg2 = inode->i_sb->s_magic;
}
}
}
out_release:
path_put(&nd.path);
out:
return err;
}
/*
* This is called every time the dcache has a lookup hit,
* and we should check whether we can really trust that
* lookup.
*
* NOTE! The hit can be a negative hit too, don't assume
* we have an inode!
*
* If the parent directory is seen to have changed, we throw out the
* cached dentry and do a new lookup.
*/
static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
{
struct inode *dir;
struct inode *inode;
struct dentry *parent;
int error;
struct nfs_fh fhandle;
struct nfs_fattr fattr;
unsigned long verifier;
int isopen = 0;
parent = dget_parent(dentry);
lock_kernel();
dir = parent->d_inode;
inode = dentry->d_inode;
if (nd && !(nd->flags & LOOKUP_CONTINUE) && (nd->flags & LOOKUP_OPEN))
isopen = 1;
if (!inode) {
if (nfs_neg_need_reval(dir, dentry, nd))
goto out_bad;
goto out_valid;
}
if (is_bad_inode(inode)) {
dfprintk(VFS, "nfs_lookup_validate: %s/%s has dud inode\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
goto out_bad;
}
/* Revalidate parent directory attribute cache */
nfs_revalidate_inode(NFS_SERVER(dir), dir);
/* Force a full look up iff the parent directory has changed */
if (nfs_check_verifier(dir, dentry)) {
if (nfs_lookup_verify_inode(inode, isopen))
goto out_zap_parent;
goto out_valid;
}
/*
* Note: we're not holding inode->i_sem and so may be racing with
* operations that change the directory. We therefore save the
* change attribute *before* we do the RPC call.
*/
verifier = nfs_save_change_attribute(dir);
error = nfs_cached_lookup(dir, dentry, &fhandle, &fattr);
if (!error) {
if (memcmp(NFS_FH(inode), &fhandle, sizeof(struct nfs_fh))!= 0)
goto out_bad;
if (nfs_lookup_verify_inode(inode, isopen))
goto out_zap_parent;
goto out_valid_renew;
}
if (NFS_STALE(inode))
goto out_bad;
error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, &fhandle, &fattr);
if (error)
goto out_bad;
if (memcmp(NFS_FH(inode), &fhandle, sizeof(struct nfs_fh))!= 0)
goto out_bad;
if ((error = nfs_refresh_inode(inode, &fattr)) != 0)
goto out_bad;
out_valid_renew:
nfs_renew_times(dentry);
nfs_set_verifier(dentry, verifier);
out_valid:
unlock_kernel();
dput(parent);
return 1;
out_zap_parent:
nfs_zap_caches(dir);
out_bad:
NFS_CACHEINV(dir);
if (inode && S_ISDIR(inode->i_mode)) {
/* Purge readdir caches. */
nfs_zap_caches(inode);
/* If we have submounts, don't unhash ! */
if (have_submounts(dentry))
goto out_valid;
shrink_dcache_parent(dentry);
}
d_drop(dentry);
unlock_kernel();
dput(parent);
return 0;
}
