static int remove_file(struct dentry *parent, char *name)
{
struct dentry *tmp;
int ret;
tmp = lookup_one_len(name, parent, strlen(name));
if (IS_ERR(tmp)) {
ret = PTR_ERR(tmp);
goto bail;
}
spin_lock(&dcache_lock);
spin_lock(&tmp->d_lock);
if (!(d_unhashed(tmp) && tmp->d_inode)) {
dget_locked(tmp);
__d_drop(tmp);
spin_unlock(&tmp->d_lock);
spin_unlock(&dcache_lock);
simple_unlink(parent->d_inode, tmp);
} else {
spin_unlock(&tmp->d_lock);
spin_unlock(&dcache_lock);
}
ret = 0;
bail:
/*
* We don't expect clients to care about the return value, but
* it's there if they need it.
*/
return ret;
}
/* this should be provided by each filesystem in an nfsd_operations interface as
* iget isn't really the right interface
*/
static struct dentry *nfsd_iget(struct super_block *sb, unsigned long ino, __u32 generation)
{
/* iget isn't really right if the inode is currently unallocated!!
* This should really all be done inside each filesystem
*
* ext2fs' read_inode has been strengthed to return a bad_inode if the inode
* had been deleted.
*
* Currently we don't know the generation for parent directory, so a generation
* of 0 means "accept any"
*/
struct inode *inode;
struct list_head *lp;
struct dentry *result;
if (ino == 0)
return ERR_PTR(-ESTALE);
inode = iget(sb, ino);
if (inode == NULL)
return ERR_PTR(-ENOMEM);
if (is_bad_inode(inode)
|| (generation && inode->i_generation != generation)
) {
/* we didn't find the right inode.. */
dprintk("fh_verify: Inode %lu, Bad count: %d %d or version %u %u\n",
inode->i_ino,
inode->i_nlink, atomic_read(&inode->i_count),
inode->i_generation,
generation);
iput(inode);
return ERR_PTR(-ESTALE);
}
/* now to find a dentry.
* If possible, get a well-connected one
*/
spin_lock(&dcache_lock);
for (lp = inode->i_dentry.next; lp != &inode->i_dentry ; lp=lp->next) {
result = list_entry(lp,struct dentry, d_alias);
if (! (result->d_flags & DCACHE_NFSD_DISCONNECTED)) {
dget_locked(result);
result->d_vfs_flags |= DCACHE_REFERENCED;
spin_unlock(&dcache_lock);
iput(inode);
return result;
}
}
spin_unlock(&dcache_lock);
result = d_alloc_root(inode);
if (result == NULL) {
iput(inode);
return ERR_PTR(-ENOMEM);
}
result->d_flags |= DCACHE_NFSD_DISCONNECTED;
return result;
}
static struct dentry *decode_by_ino(struct super_block *sb, ino_t ino,
ino_t dir_ino)
{
struct dentry *dentry, *d;
struct inode *inode;
au_gen_t sigen;
LKTRTrace("i%lu, diri%lu\n",
(unsigned long)ino, (unsigned long)dir_ino);
dentry = NULL;
inode = ilookup(sb, ino);
if (!inode)
goto out;
dentry = ERR_PTR(-ESTALE);
sigen = au_sigen(sb);
if (unlikely(is_bad_inode(inode)
|| IS_DEADDIR(inode)
|| sigen != au_iigen(inode)))
goto out_iput;
dentry = NULL;
if (!dir_ino || S_ISDIR(inode->i_mode))
dentry = d_find_alias(inode);
else {
spin_lock(&dcache_lock);
list_for_each_entry(d, &inode->i_dentry, d_alias)
if (!au_test_anon(d)
&& d->d_parent->d_inode->i_ino == dir_ino) {
dentry = dget_locked(d);
break;
}
spin_unlock(&dcache_lock);
}
if (unlikely(dentry && sigen != au_digen(dentry))) {
dput(dentry);
dentry = ERR_PTR(-ESTALE);
}
out_iput:
iput(inode);
out:
AuTraceErrPtr(dentry);
return dentry;
}
void sysfs_remove_dir(struct kobject * kobj)
{
struct list_head * node;
struct dentry * dentry = dget(kobj->dentry);
if (!dentry)
return;
pr_debug("sysfs %s: removing dir\n",dentry->d_name.name);
down(&dentry->d_inode->i_sem);
spin_lock(&dcache_lock);
node = dentry->d_subdirs.next;
while (node != &dentry->d_subdirs) {
struct dentry * d = list_entry(node,struct dentry,d_child);
list_del_init(node);
pr_debug(" o %s (%d): ",d->d_name.name,atomic_read(&d->d_count));
if (d->d_inode) {
d = dget_locked(d);
pr_debug("removing");
/**
* Unlink and unhash.
*/
spin_unlock(&dcache_lock);
d_delete(d);
simple_unlink(dentry->d_inode,d);
dput(d);
spin_lock(&dcache_lock);
}
pr_debug(" done\n");
node = dentry->d_subdirs.next;
}
list_del_init(&dentry->d_child);
spin_unlock(&dcache_lock);
up(&dentry->d_inode->i_sem);
remove_dir(dentry);
/**
* Drop reference from dget() on entrance.
*/
dput(dentry);
}
static int remove_file(struct dentry *parent, char *name)
{
struct dentry *tmp;
int ret;
tmp = lookup_one_len(name, parent, strlen(name));
if (IS_ERR(tmp)) {
ret = PTR_ERR(tmp);
goto bail;
}
#if (LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,36))
spin_lock(&dcache_lock);
#endif
spin_lock(&tmp->d_lock);
if (!(d_unhashed(tmp) && tmp->d_inode)) {
#if (LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,36))
dget_locked(tmp);
#else
dget_dlock(tmp);
#endif
__d_drop(tmp);
spin_unlock(&tmp->d_lock);
#if (LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,36))
spin_unlock(&dcache_lock);
#endif
simple_unlink(parent->d_inode, tmp);
} else {
spin_unlock(&tmp->d_lock);
#if (LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,36))
spin_unlock(&dcache_lock);
#endif
}
ret = 0;
bail:
/*
* We don't expect clients to care about the return value, but
* it's there if they need it.
*/
return ret;
}
/**
* sysfs_drop_dentry - drop dentry for the specified sysfs_dirent
* @sd: target sysfs_dirent
*
* Drop dentry for @sd. @sd must have been unlinked from its
* parent on entry to this function such that it can't be looked
* up anymore.
*
* @sd->s_dentry which is protected with sysfs_assoc_lock points
* to the currently associated dentry but we're not holding a
* reference to it and racing with dput(). Grab dcache_lock and
* verify dentry before dropping it. If @sd->s_dentry is NULL or
* dput() beats us, no need to bother.
*/
static void sysfs_drop_dentry(struct sysfs_dirent *sd)
{
struct dentry *dentry = NULL;
struct inode *inode;
/* We're not holding a reference to ->s_dentry dentry but the
* field will stay valid as long as sysfs_assoc_lock is held.
*/
spin_lock(&sysfs_assoc_lock);
spin_lock(&dcache_lock);
/* drop dentry if it's there and dput() didn't kill it yet */
if (sd->s_dentry && sd->s_dentry->d_inode) {
dentry = dget_locked(sd->s_dentry);
spin_lock(&dentry->d_lock);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
}
spin_unlock(&dcache_lock);
spin_unlock(&sysfs_assoc_lock);
/* dentries for shadowed inodes are pinned, unpin */
if (dentry && sysfs_is_shadowed_inode(dentry->d_inode))
dput(dentry);
dput(dentry);
/* adjust nlink and update timestamp */
inode = ilookup(sysfs_sb, sd->s_ino);
if (inode) {
mutex_lock(&inode->i_mutex);
inode->i_ctime = CURRENT_TIME;
drop_nlink(inode);
if (sysfs_type(sd) == SYSFS_DIR)
drop_nlink(inode);
mutex_unlock(&inode->i_mutex);
iput(inode);
}
}
int
osi_TryEvictVCache(struct vcache *avc, int *slept, int defersleep) {
int code;
struct dentry *dentry;
struct list_head *cur, *head;
/* First, see if we can evict the inode from the dcache */
if (defersleep && avc != afs_globalVp && VREFCOUNT(avc) > 1 && avc->opens == 0) {
*slept = 1;
ReleaseWriteLock(&afs_xvcache);
AFS_GUNLOCK();
afs_linux_lock_dcache();
head = &(AFSTOV(avc))->i_dentry;
restart:
cur = head;
while ((cur = cur->next) != head) {
dentry = list_entry(cur, struct dentry, d_alias);
if (d_unhashed(dentry))
continue;
dget_locked(dentry);
afs_linux_unlock_dcache();
if (d_invalidate(dentry) == -EBUSY) {
dput(dentry);
/* perhaps lock and try to continue? (use cur as head?) */
goto inuse;
}
dput(dentry);
afs_linux_lock_dcache();
goto restart;
}
afs_linux_unlock_dcache();
inuse:
AFS_GLOCK();
ObtainWriteLock(&afs_xvcache, 733);
}
/* Drop dentry if it is not used already, unhash otherwise.
Should be called with dcache lock held!
Returns: 1 if dentry was dropped, 0 if unhashed. */
int ll_drop_dentry(struct dentry *dentry)
{
lock_dentry(dentry);
if (atomic_read(&dentry->d_count) == 0) {
CDEBUG(D_DENTRY, "deleting dentry %.*s (%p) parent %p "
"inode %p\n", dentry->d_name.len,
dentry->d_name.name, dentry, dentry->d_parent,
dentry->d_inode);
dget_locked(dentry);
__d_drop(dentry);
unlock_dentry(dentry);
spin_unlock(&dcache_lock);
cfs_spin_unlock(&ll_lookup_lock);
dput(dentry);
cfs_spin_lock(&ll_lookup_lock);
spin_lock(&dcache_lock);
return 1;
}
/* disconected dentry can not be find without lookup, because we
* not need his to unhash or mark invalid. */
if (dentry->d_flags & DCACHE_DISCONNECTED) {
unlock_dentry(dentry);
RETURN (0);
}
if (!(dentry->d_flags & DCACHE_LUSTRE_INVALID)) {
CDEBUG(D_DENTRY, "unhashing dentry %.*s (%p) parent %p "
"inode %p refc %d\n", dentry->d_name.len,
dentry->d_name.name, dentry, dentry->d_parent,
dentry->d_inode, atomic_read(&dentry->d_count));
/* actually we don't unhash the dentry, rather just
* mark it inaccessible for to __d_lookup(). otherwise
* sys_getcwd() could return -ENOENT -bzzz */
dentry->d_flags |= DCACHE_LUSTRE_INVALID;
if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
__d_drop(dentry);
}
unlock_dentry(dentry);
return 0;
}
static void sel_remove_entries(struct dentry *de)
{
struct list_head *node;
spin_lock(&dcache_lock);
node = de->d_subdirs.next;
while (node != &de->d_subdirs) {
struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
list_del_init(node);
if (d->d_inode) {
d = dget_locked(d);
spin_unlock(&dcache_lock);
d_delete(d);
simple_unlink(de->d_inode, d);
dput(d);
spin_lock(&dcache_lock);
}
node = de->d_subdirs.next;
}
spin_unlock(&dcache_lock);
}
/*
* dget, but require that fpos and parent matches what the dentry contains.
* dentry is not known to be a valid pointer at entry.
*/
struct dentry *
smb_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 <= SMB_MAXNAMELEN &&
(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;
goto out_unlock;
}
next = next->next;
}
dent = NULL;
out_unlock:
spin_unlock(&dcache_lock);
return dent;
}
static int au_dpages_append(struct au_dcsub_pages *dpages,
struct dentry *dentry, gfp_t gfp)
{
int err, sz;
struct au_dpage *dpage;
void *p;
dpage = dpages->dpages + dpages->ndpage - 1;
sz = PAGE_SIZE / sizeof(dentry);
if (unlikely(dpage->ndentry >= sz)) {
AuLabel(new dpage);
err = -ENOMEM;
sz = dpages->ndpage * sizeof(*dpages->dpages);
p = au_kzrealloc(dpages->dpages, sz,
sz + sizeof(*dpages->dpages), gfp);
if (unlikely(!p))
goto out;
dpages->dpages = p;
dpage = dpages->dpages + dpages->ndpage;
p = (void *)__get_free_page(gfp);
if (unlikely(!p))
goto out;
dpage->ndentry = 0;
dpage->dentries = p;
dpages->ndpage++;
}
/* d_count can be zero */
dpage->dentries[dpage->ndentry++] = dget_locked(dentry);
return 0; /* success */
out:
return err;
}
/**
* ntfs_lookup - find the inode represented by a dentry in a directory inode
* @dir_ino: directory inode in which to look for the inode
* @dent: dentry representing the inode to look for
* @nd: lookup nameidata
*
* In short, ntfs_lookup() looks for the inode represented by the dentry @dent
* in the directory inode @dir_ino and if found attaches the inode to the
* dentry @dent.
*
* In more detail, the dentry @dent specifies which inode to look for by
* supplying the name of the inode in @dent->d_name.name. ntfs_lookup()
* converts the name to Unicode and walks the contents of the directory inode
* @dir_ino looking for the converted Unicode name. If the name is found in the
* directory, the corresponding inode is loaded by calling ntfs_iget() on its
* inode number and the inode is associated with the dentry @dent via a call to
* d_splice_alias().
*
* If the name is not found in the directory, a NULL inode is inserted into the
* dentry @dent via a call to d_add(). The dentry is then termed a negative
* dentry.
*
* Only if an actual error occurs, do we return an error via ERR_PTR().
*
* In order to handle the case insensitivity issues of NTFS with regards to the
* dcache and the dcache requiring only one dentry per directory, we deal with
* dentry aliases that only differ in case in ->ntfs_lookup() while maintaining
* a case sensitive dcache. This means that we get the full benefit of dcache
* speed when the file/directory is looked up with the same case as returned by
* ->ntfs_readdir() but that a lookup for any other case (or for the short file
* name) will not find anything in dcache and will enter ->ntfs_lookup()
* instead, where we search the directory for a fully matching file name
* (including case) and if that is not found, we search for a file name that
* matches with different case and if that has non-POSIX semantics we return
* that. We actually do only one search (case sensitive) and keep tabs on
* whether we have found a case insensitive match in the process.
*
* To simplify matters for us, we do not treat the short vs long filenames as
* two hard links but instead if the lookup matches a short filename, we
* return the dentry for the corresponding long filename instead.
*
* There are three cases we need to distinguish here:
*
* 1) @dent perfectly matches (i.e. including case) a directory entry with a
* file name in the WIN32 or POSIX namespaces. In this case
* ntfs_lookup_inode_by_name() will return with name set to NULL and we
* just d_splice_alias() @dent.
* 2) @dent matches (not including case) a directory entry with a file name in
* the WIN32 namespace. In this case ntfs_lookup_inode_by_name() will return
* with name set to point to a kmalloc()ed ntfs_name structure containing
* the properly cased little endian Unicode name. We convert the name to the
* current NLS code page, search if a dentry with this name already exists
* and if so return that instead of @dent. At this point things are
* complicated by the possibility of 'disconnected' dentries due to NFS
* which we deal with appropriately (see the code comments). The VFS will
* then destroy the old @dent and use the one we returned. If a dentry is
* not found, we allocate a new one, d_splice_alias() it, and return it as
* above.
* 3) @dent matches either perfectly or not (i.e. we don't care about case) a
* directory entry with a file name in the DOS namespace. In this case
* ntfs_lookup_inode_by_name() will return with name set to point to a
* kmalloc()ed ntfs_name structure containing the mft reference (cpu endian)
* of the inode. We use the mft reference to read the inode and to find the
* file name in the WIN32 namespace corresponding to the matched short file
* name. We then convert the name to the current NLS code page, and proceed
* searching for a dentry with this name, etc, as in case 2), above.
*
* Locking: Caller must hold i_mutex on the directory.
*/
static struct dentry *ntfs_lookup(struct inode *dir_ino, struct dentry *dent,
struct nameidata *nd)
{
ntfs_volume *vol = NTFS_SB(dir_ino->i_sb);
struct inode *dent_inode;
ntfschar *uname;
ntfs_name *name = NULL;
MFT_REF mref;
unsigned long dent_ino;
int uname_len;
ntfs_debug("Looking up %s in directory inode 0x%lx.",
dent->d_name.name, dir_ino->i_ino);
/* Convert the name of the dentry to Unicode. */
uname_len = ntfs_nlstoucs(vol, dent->d_name.name, dent->d_name.len,
&uname);
if (uname_len < 0) {
if (uname_len != -ENAMETOOLONG)
ntfs_error(vol->sb, "Failed to convert name to "
"Unicode.");
return ERR_PTR(uname_len);
}
mref = ntfs_lookup_inode_by_name(NTFS_I(dir_ino), uname, uname_len,
&name);
kmem_cache_free(ntfs_name_cache, uname);
if (!IS_ERR_MREF(mref)) {
dent_ino = MREF(mref);
ntfs_debug("Found inode 0x%lx. Calling ntfs_iget.", dent_ino);
dent_inode = ntfs_iget(vol->sb, dent_ino);
if (likely(!IS_ERR(dent_inode))) {
/* Consistency check. */
if (is_bad_inode(dent_inode) || MSEQNO(mref) ==
NTFS_I(dent_inode)->seq_no ||
dent_ino == FILE_MFT) {
/* Perfect WIN32/POSIX match. -- Case 1. */
if (!name) {
ntfs_debug("Done. (Case 1.)");
return d_splice_alias(dent_inode, dent);
}
/*
* We are too indented. Handle imperfect
* matches and short file names further below.
*/
goto handle_name;
}
ntfs_error(vol->sb, "Found stale reference to inode "
"0x%lx (reference sequence number = "
"0x%x, inode sequence number = 0x%x), "
"returning -EIO. Run chkdsk.",
dent_ino, MSEQNO(mref),
NTFS_I(dent_inode)->seq_no);
iput(dent_inode);
dent_inode = ERR_PTR(-EIO);
} else
ntfs_error(vol->sb, "ntfs_iget(0x%lx) failed with "
"error code %li.", dent_ino,
PTR_ERR(dent_inode));
kfree(name);
/* Return the error code. */
return (struct dentry *)dent_inode;
}
/* It is guaranteed that @name is no longer allocated at this point. */
if (MREF_ERR(mref) == -ENOENT) {
ntfs_debug("Entry was not found, adding negative dentry.");
/* The dcache will handle negative entries. */
d_add(dent, NULL);
ntfs_debug("Done.");
return NULL;
}
ntfs_error(vol->sb, "ntfs_lookup_ino_by_name() failed with error "
"code %i.", -MREF_ERR(mref));
return ERR_PTR(MREF_ERR(mref));
// TODO: Consider moving this lot to a separate function! (AIA)
handle_name:
{
struct dentry *real_dent, *new_dent;
MFT_RECORD *m;
ntfs_attr_search_ctx *ctx;
ntfs_inode *ni = NTFS_I(dent_inode);
int err;
struct qstr nls_name;
nls_name.name = NULL;
if (name->type != FILE_NAME_DOS) { /* Case 2. */
ntfs_debug("Case 2.");
nls_name.len = (unsigned)ntfs_ucstonls(vol,
(ntfschar*)&name->name, name->len,
(unsigned char**)&nls_name.name, 0);
kfree(name);
} else /* if (name->type == FILE_NAME_DOS) */ { /* Case 3. */
FILE_NAME_ATTR *fn;
ntfs_debug("Case 3.");
kfree(name);
/* Find the WIN32 name corresponding to the matched DOS name. */
ni = NTFS_I(dent_inode);
m = map_mft_record(ni);
if (IS_ERR(m)) {
err = PTR_ERR(m);
m = NULL;
ctx = NULL;
goto err_out;
}
ctx = ntfs_attr_get_search_ctx(ni, m);
if (unlikely(!ctx)) {
err = -ENOMEM;
goto err_out;
}
do {
ATTR_RECORD *a;
u32 val_len;
err = ntfs_attr_lookup(AT_FILE_NAME, NULL, 0, 0, 0,
NULL, 0, ctx);
if (unlikely(err)) {
ntfs_error(vol->sb, "Inode corrupt: No WIN32 "
"namespace counterpart to DOS "
"file name. Run chkdsk.");
if (err == -ENOENT)
err = -EIO;
goto err_out;
}
/* Consistency checks. */
a = ctx->attr;
if (a->non_resident || a->flags)
goto eio_err_out;
val_len = le32_to_cpu(a->data.resident.value_length);
if (le16_to_cpu(a->data.resident.value_offset) +
val_len > le32_to_cpu(a->length))
goto eio_err_out;
fn = (FILE_NAME_ATTR*)((u8*)ctx->attr + le16_to_cpu(
ctx->attr->data.resident.value_offset));
if ((u32)(fn->file_name_length * sizeof(ntfschar) +
sizeof(FILE_NAME_ATTR)) > val_len)
goto eio_err_out;
} while (fn->file_name_type != FILE_NAME_WIN32);
/* Convert the found WIN32 name to current NLS code page. */
nls_name.len = (unsigned)ntfs_ucstonls(vol,
(ntfschar*)&fn->file_name, fn->file_name_length,
(unsigned char**)&nls_name.name, 0);
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(ni);
}
m = NULL;
ctx = NULL;
/* Check if a conversion error occurred. */
if ((signed)nls_name.len < 0) {
err = (signed)nls_name.len;
goto err_out;
}
nls_name.hash = full_name_hash(nls_name.name, nls_name.len);
/*
* Note: No need for dent->d_lock lock as i_mutex is held on the
* parent inode.
*/
/* Does a dentry matching the nls_name exist already? */
real_dent = d_lookup(dent->d_parent, &nls_name);
/* If not, create it now. */
if (!real_dent) {
real_dent = d_alloc(dent->d_parent, &nls_name);
kfree(nls_name.name);
if (!real_dent) {
err = -ENOMEM;
goto err_out;
}
new_dent = d_splice_alias(dent_inode, real_dent);
if (new_dent)
dput(real_dent);
else
new_dent = real_dent;
ntfs_debug("Done. (Created new dentry.)");
return new_dent;
}
kfree(nls_name.name);
/* Matching dentry exists, check if it is negative. */
if (real_dent->d_inode) {
if (unlikely(real_dent->d_inode != dent_inode)) {
/* This can happen because bad inodes are unhashed. */
BUG_ON(!is_bad_inode(dent_inode));
BUG_ON(!is_bad_inode(real_dent->d_inode));
}
/*
* Already have the inode and the dentry attached, decrement
* the reference count to balance the ntfs_iget() we did
* earlier on. We found the dentry using d_lookup() so it
* cannot be disconnected and thus we do not need to worry
* about any NFS/disconnectedness issues here.
*/
iput(dent_inode);
ntfs_debug("Done. (Already had inode and dentry.)");
return real_dent;
}
/*
* Negative dentry: instantiate it unless the inode is a directory and
* has a 'disconnected' dentry (i.e. IS_ROOT and DCACHE_DISCONNECTED),
* in which case d_move() that in place of the found dentry.
*/
if (!S_ISDIR(dent_inode->i_mode)) {
/* Not a directory; everything is easy. */
d_instantiate(real_dent, dent_inode);
ntfs_debug("Done. (Already had negative file dentry.)");
return real_dent;
}
spin_lock(&dcache_lock);
if (list_empty(&dent_inode->i_dentry)) {
/*
* Directory without a 'disconnected' dentry; we need to do
* d_instantiate() by hand because it takes dcache_lock which
* we already hold.
*/
list_add(&real_dent->d_alias, &dent_inode->i_dentry);
real_dent->d_inode = dent_inode;
spin_unlock(&dcache_lock);
security_d_instantiate(real_dent, dent_inode);
ntfs_debug("Done. (Already had negative directory dentry.)");
return real_dent;
}
/*
* Directory with a 'disconnected' dentry; get a reference to the
* 'disconnected' dentry.
*/
new_dent = list_entry(dent_inode->i_dentry.next, struct dentry,
d_alias);
dget_locked(new_dent);
spin_unlock(&dcache_lock);
/* Do security vodoo. */
security_d_instantiate(real_dent, dent_inode);
/* Move new_dent in place of real_dent. */
d_move(new_dent, real_dent);
/* Balance the ntfs_iget() we did above. */
iput(dent_inode);
/* Throw away real_dent. */
dput(real_dent);
/* Use new_dent as the actual dentry. */
ntfs_debug("Done. (Already had negative, disconnected directory "
"dentry.)");
return new_dent;
eio_err_out:
ntfs_error(vol->sb, "Illegal file name attribute. Run chkdsk.");
err = -EIO;
err_out:
if (ctx)
ntfs_attr_put_search_ctx(ctx);
if (m)
unmap_mft_record(ni);
iput(dent_inode);
ntfs_error(vol->sb, "Failed, returning error code %i.", err);
return ERR_PTR(err);
}
}
/**
* sysfs_get_dentry - get dentry for the given sysfs_dirent
* @sd: sysfs_dirent of interest
*
* Get dentry for @sd. Dentry is looked up if currently not
* present. This function climbs sysfs_dirent tree till it
* reaches a sysfs_dirent with valid dentry attached and descends
* down from there looking up dentry for each step.
*
* LOCKING:
* Kernel thread context (may sleep)
*
* RETURNS:
* Pointer to found dentry on success, ERR_PTR() value on error.
*/
struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd)
{
struct sysfs_dirent *cur;
struct dentry *parent_dentry, *dentry;
int i, depth;
/* Find the first parent which has valid s_dentry and get the
* dentry.
*/
mutex_lock(&sysfs_mutex);
restart0:
spin_lock(&sysfs_assoc_lock);
restart1:
spin_lock(&dcache_lock);
dentry = NULL;
depth = 0;
cur = sd;
while (!cur->s_dentry || !cur->s_dentry->d_inode) {
if (cur->s_flags & SYSFS_FLAG_REMOVED) {
dentry = ERR_PTR(-ENOENT);
depth = 0;
break;
}
cur = cur->s_parent;
depth++;
}
if (!IS_ERR(dentry))
dentry = dget_locked(cur->s_dentry);
spin_unlock(&dcache_lock);
spin_unlock(&sysfs_assoc_lock);
/* from the found dentry, look up depth times */
while (depth--) {
/* find and get depth'th ancestor */
for (cur = sd, i = 0; cur && i < depth; i++)
cur = cur->s_parent;
/* This can happen if tree structure was modified due
* to move/rename. Restart.
*/
if (i != depth) {
dput(dentry);
goto restart0;
}
sysfs_get(cur);
mutex_unlock(&sysfs_mutex);
/* look it up */
parent_dentry = dentry;
dentry = lookup_one_len_kern(cur->s_name, parent_dentry,
strlen(cur->s_name));
dput(parent_dentry);
if (IS_ERR(dentry)) {
sysfs_put(cur);
return dentry;
}
mutex_lock(&sysfs_mutex);
spin_lock(&sysfs_assoc_lock);
/* This, again, can happen if tree structure has
* changed and we looked up the wrong thing. Restart.
*/
if (cur->s_dentry != dentry) {
dput(dentry);
sysfs_put(cur);
goto restart1;
}
spin_unlock(&sysfs_assoc_lock);
sysfs_put(cur);
}
mutex_unlock(&sysfs_mutex);
return dentry;
}
int
osi_TryEvictVCache(struct vcache *avc, int *slept, int defersleep) {
int code;
struct dentry *dentry;
struct inode *inode = AFSTOV(avc);
struct list_head *cur, *head;
/* First, see if we can evict the inode from the dcache */
if (defersleep && avc != afs_globalVp && VREFCOUNT(avc) > 1 && avc->opens == 0) {
*slept = 1;
ReleaseWriteLock(&afs_xvcache);
AFS_GUNLOCK();
#if defined(HAVE_DCACHE_LOCK)
spin_lock(&dcache_lock);
head = &inode->i_dentry;
restart:
cur = head;
while ((cur = cur->next) != head) {
dentry = list_entry(cur, struct dentry, d_alias);
if (d_unhashed(dentry))
continue;
dget_locked(dentry);
spin_unlock(&dcache_lock);
if (d_invalidate(dentry) == -EBUSY) {
dput(dentry);
/* perhaps lock and try to continue? (use cur as head?) */
goto inuse;
}
dput(dentry);
spin_lock(&dcache_lock);
goto restart;
}
spin_unlock(&dcache_lock);
#else /* HAVE_DCACHE_LOCK */
spin_lock(&inode->i_lock);
head = &inode->i_dentry;
restart:
cur = head;
while ((cur = cur->next) != head) {
dentry = list_entry(cur, struct dentry, d_alias);
spin_lock(&dentry->d_lock);
if (d_unhashed(dentry)) {
spin_unlock(&dentry->d_lock);
continue;
}
spin_unlock(&dentry->d_lock);
dget(dentry);
spin_unlock(&inode->i_lock);
if (d_invalidate(dentry) == -EBUSY) {
dput(dentry);
/* perhaps lock and try to continue? (use cur as head?) */
goto inuse;
}
dput(dentry);
spin_lock(&inode->i_lock);
goto restart;
}
spin_unlock(&inode->i_lock);
#endif /* HAVE_DCACHE_LOCK */
inuse:
AFS_GLOCK();
ObtainWriteLock(&afs_xvcache, 733);
}
struct dentry *
find_exported_dentry(struct super_block *sb, void *obj, void *parent,
int (*acceptable)(void *context, struct dentry *de),
void *context)
{
struct dentry *result = NULL;
struct dentry *target_dir;
int err;
struct export_operations *nops = sb->s_export_op;
struct list_head *le, *head;
struct dentry *toput = NULL;
int noprogress;
/*
* Attempt to find the inode.
*/
result = CALL(sb->s_export_op,get_dentry)(sb,obj);
err = -ESTALE;
if (result == NULL)
goto err_out;
if (IS_ERR(result)) {
err = PTR_ERR(result);
goto err_out;
}
if (S_ISDIR(result->d_inode->i_mode) &&
(result->d_flags & DCACHE_DISCONNECTED)) {
/* it is an unconnected directory, we must connect it */
;
} else {
if (acceptable(context, result))
return result;
if (S_ISDIR(result->d_inode->i_mode)) {
/* there is no other dentry, so fail */
goto err_result;
}
/* try any other aliases */
spin_lock(&dcache_lock);
head = &result->d_inode->i_dentry;
list_for_each(le, head) {
struct dentry *dentry = list_entry(le, struct dentry, d_alias);
dget_locked(dentry);
spin_unlock(&dcache_lock);
if (toput)
dput(toput);
toput = NULL;
if (dentry != result &&
acceptable(context, dentry)) {
dput(result);
return dentry;
}
spin_lock(&dcache_lock);
toput = dentry;
}
spin_unlock(&dcache_lock);
if (toput)
dput(toput);
}
/* It's a directory, or we are required to confirm the file's
* location in the tree based on the parent information
*/
dprintk("find_exported_dentry: need to look harder for %s/%d\n",sb->s_id,*(int*)obj);
if (S_ISDIR(result->d_inode->i_mode))
target_dir = dget(result);
else {
if (parent == NULL)
goto err_result;
target_dir = CALL(sb->s_export_op,get_dentry)(sb,parent);
if (IS_ERR(target_dir))
err = PTR_ERR(target_dir);
if (target_dir == NULL || IS_ERR(target_dir))
goto err_result;
}
/*
* Now we need to make sure that target_dir is properly connected.
* It may already be, as the flag isn't always updated when connection
* happens.
* So, we walk up parent links until we find a connected directory,
* or we run out of directories. Then we find the parent, find
* the name of the child in that parent, and do a lookup.
* This should connect the child into the parent
* We then repeat.
*/
/* it is possible that a confused file system might not let us complete
* the path to the root. For example, if get_parent returns a directory
* in which we cannot find a name for the child. While this implies a
* very sick filesystem we don't want it to cause knfsd to spin. Hence
* the noprogress counter. If we go through the loop 10 times (2 is
* probably enough) without getting anywhere, we just give up
*/
noprogress= 0;
while (target_dir->d_flags & DCACHE_DISCONNECTED && noprogress++ < 10) {
struct dentry *pd = target_dir;
dget(pd);
spin_lock(&pd->d_lock);
while (!IS_ROOT(pd) &&
(pd->d_parent->d_flags&DCACHE_DISCONNECTED)) {
struct dentry *parent = pd->d_parent;
dget(parent);
spin_unlock(&pd->d_lock);
dput(pd);
pd = parent;
spin_lock(&pd->d_lock);
}
spin_unlock(&pd->d_lock);
if (!IS_ROOT(pd)) {
/* must have found a connected parent - great */
spin_lock(&pd->d_lock);
pd->d_flags &= ~DCACHE_DISCONNECTED;
spin_unlock(&pd->d_lock);
noprogress = 0;
} else if (pd == sb->s_root) {
printk(KERN_ERR "export: Eeek filesystem root is not connected, impossible\n");
spin_lock(&pd->d_lock);
pd->d_flags &= ~DCACHE_DISCONNECTED;
spin_unlock(&pd->d_lock);
noprogress = 0;
} else {
/* we have hit the top of a disconnected path. Try
* to find parent and connect
* note: racing with some other process renaming a
* directory isn't much of a problem here. If someone
* renames the directory, it will end up properly
* connected, which is what we want
*/
struct dentry *ppd;
struct dentry *npd;
char nbuf[NAME_MAX+1];
down(&pd->d_inode->i_sem);
ppd = CALL(nops,get_parent)(pd);
up(&pd->d_inode->i_sem);
if (IS_ERR(ppd)) {
err = PTR_ERR(ppd);
dprintk("find_exported_dentry: get_parent of %ld failed, err %d\n",
pd->d_inode->i_ino, err);
dput(pd);
break;
}
dprintk("find_exported_dentry: find name of %lu in %lu\n", pd->d_inode->i_ino, ppd->d_inode->i_ino);
err = CALL(nops,get_name)(ppd, nbuf, pd);
if (err) {
dput(ppd);
dput(pd);
if (err == -ENOENT)
/* some race between get_parent and
* get_name? just try again
*/
continue;
break;
}
dprintk("find_exported_dentry: found name: %s\n", nbuf);
down(&ppd->d_inode->i_sem);
npd = lookup_one_len(nbuf, ppd, strlen(nbuf));
up(&ppd->d_inode->i_sem);
if (IS_ERR(npd)) {
err = PTR_ERR(npd);
dprintk("find_exported_dentry: lookup failed: %d\n", err);
dput(ppd);
dput(pd);
break;
}
/* we didn't really want npd, we really wanted
* a side-effect of the lookup.
* hopefully, npd == pd, though it isn't really
* a problem if it isn't
*/
if (npd == pd)
noprogress = 0;
else
printk("find_exported_dentry: npd != pd\n");
dput(npd);
dput(ppd);
if (IS_ROOT(pd)) {
/* something went wrong, we have to give up */
dput(pd);
break;
}
}
dput(pd);
}
if (target_dir->d_flags & DCACHE_DISCONNECTED) {
/* something went wrong - oh-well */
if (!err)
err = -ESTALE;
goto err_target;
}
/* if we weren't after a directory, have one more step to go */
if (result != target_dir) {
struct dentry *nresult;
char nbuf[NAME_MAX+1];
err = CALL(nops,get_name)(target_dir, nbuf, result);
if (!err) {
down(&target_dir->d_inode->i_sem);
nresult = lookup_one_len(nbuf, target_dir, strlen(nbuf));
up(&target_dir->d_inode->i_sem);
if (!IS_ERR(nresult)) {
if (nresult->d_inode) {
dput(result);
result = nresult;
} else
dput(nresult);
}
}
}
dput(target_dir);
/* now result is properly connected, it is our best bet */
if (acceptable(context, result))
return result;
/* one last try of the aliases.. */
spin_lock(&dcache_lock);
toput = NULL;
head = &result->d_inode->i_dentry;
list_for_each(le, head) {
struct dentry *dentry = list_entry(le, struct dentry, d_alias);
dget_locked(dentry);
spin_unlock(&dcache_lock);
if (toput) dput(toput);
if (dentry != result &&
acceptable(context, dentry)) {
dput(result);
return dentry;
}
spin_lock(&dcache_lock);
toput = dentry;
}
spin_unlock(&dcache_lock);
if (toput)
dput(toput);
/* drat - I just cannot find anything acceptable */
dput(result);
/* It might be justifiable to return ESTALE here,
* but the filehandle at-least looks reasonable good
* and it just be a permission problem, so returning
* -EACCESS is safer
*/
return ERR_PTR(-EACCES);
err_target:
dput(target_dir);
err_result:
dput(result);
err_out:
return ERR_PTR(err);
}
