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|
/*
* You can put anything here - it doesn't even have to be a comment - and it
* will be ignored until we reach the first template-name comment.
*/
/* template-name read-fop */
int32_t
jbr_@NAME@ (call_frame_t *frame, xlator_t *this,
@LONG_ARGS@)
{
jbr_private_t *priv = NULL;
gf_boolean_t in_recon = _gf_false;
int32_t op_errno = 0;
int32_t recon_term, recon_index;
GF_VALIDATE_OR_GOTO ("jbr", this, err);
priv = this->private;
GF_VALIDATE_OR_GOTO (this->name, priv, err);
GF_VALIDATE_OR_GOTO (this->name, frame, err);
op_errno = EREMOTE;
/* allow reads during reconciliation *
* TBD: allow "dirty" reads on non-leaders *
*/
if (xdata &&
(dict_get_int32(xdata, RECON_TERM_XATTR, &recon_term) == 0) &&
(dict_get_int32(xdata, RECON_INDEX_XATTR, &recon_index) == 0)) {
in_recon = _gf_true;
}
if ((!priv->leader) && (in_recon == _gf_false)) {
goto err;
}
STACK_WIND (frame, default_@NAME@_cbk,
FIRST_CHILD(this), FIRST_CHILD(this)->fops->@NAME@,
@SHORT_ARGS@);
return 0;
err:
STACK_UNWIND_STRICT (@NAME@, frame, -1, op_errno,
@ERROR_ARGS@);
return 0;
}
/* template-name read-perform_local_op */
/* No "perform_local_op" function needed for @NAME@ */
/* template-name read-dispatch */
/* No "dispatch" function needed for @NAME@ */
/* template-name read-call_dispatch */
/* No "call_dispatch" function needed for @NAME@ */
/* template-name read-fan-in */
/* No "fan-in" function needed for @NAME@ */
/* template-name read-continue */
/* No "continue" function needed for @NAME@ */
/* template-name read-complete */
/* No "complete" function needed for @NAME@ */
/* template-name write-fop */
int32_t
jbr_@NAME@ (call_frame_t *frame, xlator_t *this,
@LONG_ARGS@)
{
jbr_local_t *local = NULL;
jbr_private_t *priv = NULL;
int32_t ret = -1;
int op_errno = ENOMEM;
GF_VALIDATE_OR_GOTO ("jbr", this, err);
priv = this->private;
GF_VALIDATE_OR_GOTO (this->name, priv, err);
GF_VALIDATE_OR_GOTO (this->name, frame, err);
#if defined(JBR_CG_NEED_FD)
ret = jbr_leader_checks_and_init (frame, this, &op_errno, xdata, fd);
#else
ret = jbr_leader_checks_and_init (frame, this, &op_errno, xdata, NULL);
#endif
if (ret)
goto err;
local = frame->local;
/*
* If we let it through despite not being the leader, then we just want
* to pass it on down without all of the additional xattrs, queuing, and
* so on. However, jbr_*_complete does depend on the initialization
* immediately above this.
*/
if (!priv->leader) {
STACK_WIND (frame, jbr_@NAME@_complete,
FIRST_CHILD(this), FIRST_CHILD(this)->fops->@NAME@,
@SHORT_ARGS@);
return 0;
}
ret = jbr_initialize_xdata_set_attrs (this, &xdata);
if (ret)
goto err;
local->stub = fop_@NAME@_stub (frame, jbr_@NAME@_continue,
@SHORT_ARGS@);
if (!local->stub) {
goto err;
}
/*
* Can be used to just call_dispatch or be customised per fop to *
* perform ops specific to that particular fop. *
*/
ret = jbr_@NAME@_perform_local_op (frame, this, &op_errno,
@SHORT_ARGS@);
if (ret)
goto err;
return ret;
err:
if (local) {
if (local->stub) {
call_stub_destroy(local->stub);
}
if (local->qstub) {
call_stub_destroy(local->qstub);
}
if (local->fd) {
fd_unref(local->fd);
}
mem_put(local);
}
STACK_UNWIND_STRICT (@NAME@, frame, -1, op_errno,
@ERROR_ARGS@);
return 0;
}
/* template-name write-perform_local_op */
int32_t
jbr_@NAME@_perform_local_op (call_frame_t *frame, xlator_t *this, int *op_errno,
@LONG_ARGS@)
{
int32_t ret = -1;
GF_VALIDATE_OR_GOTO ("jbr", this, out);
GF_VALIDATE_OR_GOTO (this->name, frame, out);
GF_VALIDATE_OR_GOTO (this->name, op_errno, out);
ret = jbr_@NAME@_call_dispatch (frame, this, op_errno,
@SHORT_ARGS@);
out:
return ret;
}
/* template-name write-call_dispatch */
int32_t
jbr_@NAME@_call_dispatch (call_frame_t *frame, xlator_t *this, int *op_errno,
@LONG_ARGS@)
{
jbr_local_t *local = NULL;
jbr_private_t *priv = NULL;
int32_t ret = -1;
GF_VALIDATE_OR_GOTO ("jbr", this, out);
priv = this->private;
GF_VALIDATE_OR_GOTO (this->name, priv, out);
GF_VALIDATE_OR_GOTO (this->name, frame, out);
local = frame->local;
GF_VALIDATE_OR_GOTO (this->name, local, out);
GF_VALIDATE_OR_GOTO (this->name, op_errno, out);
#if defined(JBR_CG_QUEUE)
jbr_inode_ctx_t *ictx = jbr_get_inode_ctx(this, fd->inode);
if (!ictx) {
*op_errno = EIO;
goto out;
}
LOCK(&ictx->lock);
if (ictx->active) {
gf_msg_debug (this->name, 0,
"queuing request due to conflict");
/*
* TBD: enqueue only for real conflict
*
* Currently we just act like all writes are in
* conflict with one another. What we should really do
* is check the active/pending queues and defer only if
* there's a conflict there.
*
* It's important to check the pending queue because we
* might have an active request X which conflicts with
* a pending request Y, and this request Z might
* conflict with Y but not X. If we checked only the
* active queue then Z could jump ahead of Y, which
* would be incorrect.
*/
local->qstub = fop_@NAME@_stub (frame,
jbr_@NAME@_dispatch,
@SHORT_ARGS@);
if (!local->qstub) {
UNLOCK(&ictx->lock);
goto out;
}
list_add_tail(&local->qlinks, &ictx->pqueue);
++(ictx->pending);
UNLOCK(&ictx->lock);
ret = 0;
goto out;
} else {
list_add_tail(&local->qlinks, &ictx->aqueue);
++(ictx->active);
}
UNLOCK(&ictx->lock);
#endif
ret = jbr_@NAME@_dispatch (frame, this, @SHORT_ARGS@);
out:
return ret;
}
/* template-name write-dispatch */
int32_t
jbr_@NAME@_dispatch (call_frame_t *frame, xlator_t *this,
@LONG_ARGS@)
{
jbr_local_t *local = NULL;
jbr_private_t *priv = NULL;
int32_t ret = -1;
xlator_list_t *trav;
GF_VALIDATE_OR_GOTO ("jbr", this, out);
priv = this->private;
GF_VALIDATE_OR_GOTO (this->name, priv, out);
GF_VALIDATE_OR_GOTO (this->name, frame, out);
local = frame->local;
GF_VALIDATE_OR_GOTO (this->name, local, out);
/*
* TBD: unblock pending request(s) if we fail after this point but
* before we get to jbr_@NAME@_complete (where that code currently
* resides).
*/
local->call_count = priv->n_children - 1;
local->successful_acks = 0;
for (trav = this->children->next; trav; trav = trav->next) {
STACK_WIND (frame, jbr_@NAME@_fan_in,
trav->xlator, trav->xlator->fops->@NAME@,
@SHORT_ARGS@);
}
/* TBD: variable Issue count */
ret = 0;
out:
return ret;
}
/* template-name write-fan-in */
int32_t
jbr_@NAME@_fan_in (call_frame_t *frame, void *cookie, xlator_t *this,
int32_t op_ret, int32_t op_errno,
@LONG_ARGS@)
{
jbr_local_t *local = NULL;
int32_t ret = -1;
uint8_t call_count;
GF_VALIDATE_OR_GOTO ("jbr", this, out);
GF_VALIDATE_OR_GOTO (this->name, frame, out);
local = frame->local;
GF_VALIDATE_OR_GOTO (this->name, local, out);
gf_msg_trace (this->name, 0, "op_ret = %d, op_errno = %d\n",
op_ret, op_errno);
LOCK(&frame->lock);
call_count = --(local->call_count);
if (op_ret != -1) {
/* Increment the number of successful acks *
* received for the operation. *
*/
(local->successful_acks)++;
local->successful_op_ret = op_ret;
}
gf_msg_debug (this->name, 0, "succ_acks = %d, op_ret = %d, op_errno = %d\n",
op_ret, op_errno, local->successful_acks);
UNLOCK(&frame->lock);
/* TBD: variable Completion count */
if (call_count == 0) {
call_resume(local->stub);
}
ret = 0;
out:
return ret;
}
/* template-name write-continue */
int32_t
jbr_@NAME@_continue (call_frame_t *frame, xlator_t *this,
@LONG_ARGS@)
{
gf_boolean_t result = _gf_false;
jbr_local_t *local = NULL;
jbr_private_t *priv = NULL;
GF_VALIDATE_OR_GOTO ("jbr", this, out);
GF_VALIDATE_OR_GOTO (this->name, frame, out);
priv = this->private;
local = frame->local;
GF_VALIDATE_OR_GOTO (this->name, priv, out);
GF_VALIDATE_OR_GOTO (this->name, local, out);
/* Perform quorum check to see if the leader needs *
* to perform the operation. If the operation will not *
* meet quorum irrespective of the leader's result *
* there is no point in the leader performing the fop *
*/
result = fop_quorum_check (this, (double)priv->n_children,
(double)local->successful_acks + 1);
if (result == _gf_false) {
gf_msg (this->name, GF_LOG_ERROR, EROFS,
J_MSG_QUORUM_NOT_MET, "Didn't receive enough acks "
"to meet quorum. Failing the operation without trying "
"it on the leader.");
STACK_UNWIND_STRICT (@NAME@, frame, -1, EROFS,
@ERROR_ARGS@);
} else {
STACK_WIND (frame, jbr_@NAME@_complete,
FIRST_CHILD(this), FIRST_CHILD(this)->fops->@NAME@,
@SHORT_ARGS@);
}
out:
return 0;
}
/* template-name write-complete */
int32_t
jbr_@NAME@_complete (call_frame_t *frame, void *cookie, xlator_t *this,
int32_t op_ret, int32_t op_errno,
@LONG_ARGS@)
{
#if defined(JBR_CG_QUEUE)
int32_t ret = -1;
#endif
gf_boolean_t result = _gf_false;
jbr_private_t *priv = NULL;
jbr_local_t *local = NULL;
GF_VALIDATE_OR_GOTO ("jbr", this, err);
GF_VALIDATE_OR_GOTO (this->name, frame, err);
priv = this->private;
local = frame->local;
GF_VALIDATE_OR_GOTO (this->name, priv, err);
GF_VALIDATE_OR_GOTO (this->name, local, err);
/* If the fop failed on the leader, then reduce one succesful ack
* before calculating the fop quorum
*/
LOCK(&frame->lock);
if (op_ret == -1)
(local->successful_acks)--;
UNLOCK(&frame->lock);
#if defined(JBR_CG_QUEUE)
ret = jbr_remove_from_queue (frame, this);
if (ret)
goto err;
#endif
#if defined(JBR_CG_FSYNC)
jbr_mark_fd_dirty(this, local);
#endif
#if defined(JBR_CG_NEED_FD)
fd_unref(local->fd);
#endif
/* After the leader completes the fop, a quorum check is *
* performed, taking into account the outcome of the fop *
* on the leader. Irrespective of the fop being successful *
* or failing on the leader, the result of the quorum will *
* determine if the overall fop is successful or not. For *
* example, a fop might have succeeded on every node except *
* the leader, in which case as quorum is being met, the fop *
* will be treated as a successful fop, even though it failed *
* on the leader. On follower nodes, no quorum check should *
* be done, and the result is returned to the leader as is. *
*/
if (priv->leader) {
result = fop_quorum_check (this, (double)priv->n_children,
(double)local->successful_acks + 1);
if (result == _gf_false) {
op_ret = -1;
op_errno = EROFS;
gf_msg (this->name, GF_LOG_ERROR, EROFS,
J_MSG_QUORUM_NOT_MET, "Quorum is not met. "
"The operation has failed.");
} else {
#if defined(JBR_CG_NEED_FD)
op_ret = local->successful_op_ret;
#else
op_ret = 0;
#endif
op_errno = 0;
gf_msg_debug (this->name, 0,
"Quorum has met. The operation has succeeded.");
}
}
STACK_UNWIND_STRICT (@NAME@, frame, op_ret, op_errno,
@SHORT_ARGS@);
return 0;
err:
STACK_UNWIND_STRICT (@NAME@, frame, -1, 0,
@SHORT_ARGS@);
return 0;
}
|
