EXIT;
}
+/* Compare if two dentries are the same. Don't match if the existing dentry
+ * is marked DCACHE_LUSTRE_INVALID. Returns 1 if different, 0 if the same.
+ *
+ * This avoids a race where ll_lookup_it() instantiates a dentry, but we get
+ * an AST before calling d_revalidate_it(). The dentry still exists (marked
+ * INVALID) so d_lookup() matches it, but we have no lock on it (so
+ * lock_match() fails) and we spin around real_lookup(). */
+static int ll_dcompare(struct dentry *parent, struct qstr *d_name,
+ struct qstr *name){
+ struct dentry *dchild;
+ ENTRY;
+
+ if (d_name->len != name->len)
+ RETURN(1);
+
+ if (memcmp(d_name->name, name->name, name->len))
+ RETURN(1);
+
+ dchild = container_of(d_name, struct dentry, d_name); /* ugh */
+ if (dchild->d_flags & DCACHE_LUSTRE_INVALID) {
+ CDEBUG(D_DENTRY,"INVALID dentry %p not matched, was bug 3784\n",
+ dchild);
+ RETURN(1);
+ }
+
+ RETURN(0);
+}
+
/* should NOT be called with the dcache lock, see fs/dcache.c */
static int ll_ddelete(struct dentry *de)
{
ENTRY;
LASSERT(de != NULL);
- CDEBUG(D_DENTRY, "ldd on dentry %*s (%p) parent %p inode %p refc %d\n",
+ CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
atomic_read(&de->d_count));
lock_kernel();
EXIT;
}
-void ll_intent_free(struct lookup_intent *it)
-{
- if (it->d.fs_data) {
- OBD_SLAB_FREE(it->d.fs_data, ll_intent_slab,
- sizeof(struct lustre_intent_data));
- it->d.fs_data = NULL;
- }
-}
-
void ll_unhash_aliases(struct inode *inode)
{
struct list_head *tmp, *head;
if (inode == NULL) {
CERROR("unexpected NULL inode, tell phil\n");
+ EXIT;
return;
}
while ((tmp = tmp->next) != head) {
struct dentry *dentry = list_entry(tmp, struct dentry, d_alias);
if (atomic_read(&dentry->d_count) == 0) {
- CDEBUG(D_DENTRY, "deleting dentry %*s (%p) parent %p "
+ 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);
dput(dentry);
goto restart;
} else if (!(dentry->d_flags & DCACHE_LUSTRE_INVALID)) {
- CDEBUG(D_DENTRY, "unhashing dentry %*s (%p) parent %p "
+ 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));
return 0;
}
OBD_SLAB_ALLOC(it->d.fs_data, ll_intent_slab, SLAB_KERNEL,
- sizeof(struct lustre_intent_data));
+ sizeof(struct lustre_intent_data));
if (!it->d.fs_data) {
CERROR("Failed to allocate memory for lustre specific intent "
"data\n");
}
it->it_op_release = ll_intent_release;
-
return 0;
}
+void ll_intent_free(struct lookup_intent *it)
+{
+ if (it->d.fs_data) {
+ OBD_SLAB_FREE(it->d.fs_data, ll_intent_slab,
+ sizeof(struct lustre_intent_data));
+ it->d.fs_data = NULL;
+ }
+}
+
+static inline int
+ll_special_name(struct dentry *de)
+{
+ if (de->d_name.name[0] == '.') switch (de->d_name.len) {
+ case 2:
+ if (de->d_name.name[1] == '.')
+ return 1;
+ case 1:
+ return 1;
+ default:
+ return 0;
+ }
+ return 0;
+}
+
int ll_revalidate_it(struct dentry *de, int flags, struct nameidata *nd,
struct lookup_intent *it)
{
struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
struct ptlrpc_request *req = NULL;
- struct it_cb_data icbd;
struct obd_export *exp;
+ struct it_cb_data icbd;
struct lustre_id pid;
struct lustre_id cid;
- int orig_it, rc = 0;
+ int gns_it, rc = 0;
ENTRY;
- spin_lock(&de->d_lock);
-
- if ((de->d_flags & DCACHE_GNS_PENDING) &&
- !(de->d_flags & DCACHE_GNS_MOUNTING))
- {
- spin_unlock(&de->d_lock);
-
- if (nd) {
- int err = ll_gns_mount_object(de, nd->mnt);
- if (err)
- CERROR("can't mount %s, err = %d\n",
- de->d_name.name, err);
- }
- RETURN(1);
- }
- spin_unlock(&de->d_lock);
-
CDEBUG(D_VFSTRACE, "VFS Op:name=%s (%p), intent=%s\n", de->d_name.name,
de, LL_IT2STR(it));
if (nd != NULL)
nd->mnt->mnt_last_used = jiffies;
- orig_it = it ? it->it_op : IT_OPEN;
+ OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
+
+ gns_it = it ? it->it_op : IT_OPEN;
ll_frob_intent(&it, &lookup_it);
+
LASSERT(it != NULL);
if (it->it_op == IT_GETATTR) { /* We need to check for LOOKUP lock as
if (rc)
LBUG(); /* Can't think of better idea just yet */
-
rc = md_intent_lock(exp, &pid, de->d_name.name,
de->d_name.len, NULL, 0, &cid, &lookup_it,
flags, &req, ll_mdc_blocking_ast);
ll_intent_release(&lookup_it);
}
+ /* open lock stuff */
+ if ((it->it_op == IT_OPEN) && de->d_inode) {
+ struct inode *inode = de->d_inode;
+ struct ll_inode_info *lli = ll_i2info(inode);
+ struct obd_client_handle **och_p;
+ __u64 *och_usecount;
+ struct obd_device *obddev;
+ struct lustre_handle lockh;
+ int flags = LDLM_FL_BLOCK_GRANTED;
+ ldlm_policy_data_t policy = {.l_inodebits = {MDS_INODELOCK_OPEN}};
+ struct ldlm_res_id file_res_id = {.name = {id_fid(&lli->lli_id),
+ id_group(&lli->lli_id)}};
+ int lockmode;
+
+ if (it->it_flags & FMODE_WRITE) {
+ och_p = &lli->lli_mds_write_och;
+ och_usecount = &lli->lli_open_fd_write_count;
+ lockmode = LCK_CW;
+ } else if (it->it_flags & FMODE_EXEC) {
+ och_p = &lli->lli_mds_exec_och;
+ och_usecount = &lli->lli_open_fd_exec_count;
+ lockmode = LCK_PR;
+ } else {
+ och_p = &lli->lli_mds_read_och;
+ och_usecount = &lli->lli_open_fd_read_count;
+ lockmode = LCK_CR;
+ }
+
+ /* Check for the proper lock */
+ obddev = md_get_real_obd(exp, &lli->lli_id);
+ if (!ldlm_lock_match(obddev->obd_namespace, flags, &file_res_id,
+ LDLM_IBITS, &policy, lockmode, &lockh))
+ goto do_lock;
+ down(&lli->lli_och_sem);
+ if (*och_p) { /* Everything is open already, do nothing */
+ /*(*och_usecount)++; Do not let them steal our open
+ handle from under us */
+ /* XXX The code above was my original idea, but in case
+ we have the handle, but we cannot use it due to later
+ checks (e.g. O_CREAT|O_EXCL flags set), nobody
+ would decrement counter increased here. So we just
+ hope the lock won't be invalidated in between. But
+ if it would be, we'll reopen the open request to
+ MDS later during file open path */
+ up(&lli->lli_och_sem);
+ memcpy(&LUSTRE_IT(it)->it_lock_handle, &lockh,
+ sizeof(lockh));
+ LUSTRE_IT(it)->it_lock_mode = lockmode;
+ RETURN(1);
+ } else {
+ /* Hm, interesting. Lock is present, but no open
+ handle? */
+ up(&lli->lli_och_sem);
+ ldlm_lock_decref(&lockh, lockmode);
+ }
+ }
+
+do_lock:
rc = md_intent_lock(exp, &pid, de->d_name.name, de->d_name.len,
- NULL, 0, &cid, it, flags, &req,
- ll_mdc_blocking_ast);
-
- /* If req is NULL, then mdc_intent_lock only tried to do a lock match;
+ NULL, 0, &cid, it, flags, &req, ll_mdc_blocking_ast);
+ /* If req is NULL, then md_intent_lock() only tried to do a lock match;
* if all was well, it will return 1 if it found locks, 0 otherwise. */
if (req == NULL && rc >= 0) {
if (!rc)
GOTO(out, rc);
out:
- if (req != NULL && rc == 1)
+ /* If we had succesful it lookup on mds, but it happened to be negative,
+ we do not free request as it will be reused during lookup (see
+ comment in mdc/mdc_locks.c::mdc_intent_lock(). But if
+ request was not completed, we need to free it. (bug 5154) */
+ if (req != NULL && (rc == 1 || !it_disposition(it, DISP_ENQ_COMPLETE))) {
ptlrpc_req_finished(req);
+ req = NULL;
+ }
if (rc == 0) {
- if (it == &lookup_it) {
+ if (it == &lookup_it)
ll_intent_release(it);
- if (req) /* Special case: We did lookup and it failed,
- need to free request */
- ptlrpc_req_finished(req);
- }
+
ll_unhash_aliases(de->d_inode);
- return rc;
+ return 0;
+ }
+
+ /*
+ * if we found that this is possible GNS mount and dentry is still valid
+ * and may be used by system, we drop the lock and return 0, that means
+ * that re-lookup is needed. Such a way we cause real mounting only in
+ * lookup control path, which is always made with parent's i_sem taken.
+ * --umka
+ */
+ if (rc &&
+ !(!((de->d_inode->i_mode & S_ISUID) && S_ISDIR(de->d_inode->i_mode)) ||
+ !(flags & LOOKUP_CONTINUE || (gns_it & (IT_CHDIR | IT_OPEN))))) {
+ /*
+ * special "." and ".." has to be always revalidated because
+ * they never should be passed to lookup()
+ */
+ if (!ll_special_name(de)) {
+ ll_intent_drop_lock(it);
+ ll_intent_free(it);
+ ll_unhash_aliases(de->d_inode);
+ return 0;
+ }
}
CDEBUG(D_DENTRY, "revalidated dentry %*s (%p) parent %p "
"inode %p refc %d\n", de->d_name.len,
de->d_name.name, de, de->d_parent, de->d_inode,
atomic_read(&de->d_count));
+
ll_lookup_finish_locks(it, de);
de->d_flags &= ~DCACHE_LUSTRE_INVALID;
- if (it == &lookup_it)
- ll_intent_release(it);
-
- if (!((de->d_inode->i_mode & S_ISUID) && S_ISDIR(de->d_inode->i_mode)) ||
- !(flags & LOOKUP_CONTINUE || (orig_it & (IT_CHDIR | IT_OPEN))))
- return rc;
-
- if (nd && !(de->d_flags & DCACHE_GNS_MOUNTING)) {
- int err = ll_gns_mount_object(de, nd->mnt);
- if (err)
- CERROR("can't mount %s, err = %d\n",
- de->d_name.name, err);
- }
+ ll_intent_release(it);
return rc;
do_lookup:
it = &lookup_it;
if (ll_intent_alloc(it))
LBUG();
-// We did that already, right? ll_inode2id(&pid, de->d_parent->d_inode);
+
+ // We did that already, right? ll_inode2id(&pid, de->d_parent->d_inode);
rc = md_intent_lock(exp, &pid, de->d_name.name,
de->d_name.len, NULL, 0, NULL,
it, 0, &req, ll_mdc_blocking_ast);
if (rc >= 0) {
- struct mds_body *mds_body = lustre_msg_buf(req->rq_repmsg, 1, sizeof(*mds_body));
+ struct mds_body *mds_body = lustre_msg_buf(req->rq_repmsg, 1,
+ sizeof(*mds_body));
/* See if we got same inode, if not - return error */
if (id_equal_stc(&cid, &mds_body->id1))
.d_release = ll_release,
.d_iput = ll_dentry_iput,
.d_delete = ll_ddelete,
+ .d_compare = ll_dcompare,
#if 0
.d_pin = ll_pin,
.d_unpin = ll_unpin,
git://git.whamcloud.com / fs / lustre-release.git / blobdiff