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-rw-r--r--xlators/experimental/jbr-server/src/jbr.c407
1 files changed, 407 insertions, 0 deletions
diff --git a/xlators/experimental/jbr-server/src/jbr.c b/xlators/experimental/jbr-server/src/jbr.c
index a342d3b83d5..d27d8ab5140 100644
--- a/xlators/experimental/jbr-server/src/jbr.c
+++ b/xlators/experimental/jbr-server/src/jbr.c
@@ -38,6 +38,20 @@ enum {
JBR_SERVER_NEXT_ENTRY
};
+/*
+ * Need to declare jbr_lk_call_dispatch as jbr_lk_continue and *
+ * jbr_lk_perform_local_op call it, before code is generated. *
+ */
+int32_t
+jbr_lk_call_dispatch (call_frame_t *frame, xlator_t *this, int *op_errno,
+ fd_t *fd, int32_t cmd, struct gf_flock *lock,
+ dict_t *xdata);
+
+int32_t
+jbr_lk_dispatch (call_frame_t *frame, xlator_t *this,
+ fd_t *fd, int32_t cmd, struct gf_flock *lock,
+ dict_t *xdata);
+
/* Used to check the quorum of acks received after the fop
* confirming the status of the fop on all the brick processes
* for this particular subvolume
@@ -312,6 +326,399 @@ out:
return ret;
}
+int32_t
+jbr_remove_from_queue (call_frame_t *frame, xlator_t *this)
+{
+ int32_t ret = -1;
+ jbr_inode_ctx_t *ictx = NULL;
+ jbr_local_t *local = NULL;
+ jbr_local_t *next = NULL;
+
+ 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);
+
+ if (local->qlinks.next != &local->qlinks) {
+ list_del(&local->qlinks);
+ ictx = jbr_get_inode_ctx(this, local->fd->inode);
+ if (ictx) {
+ LOCK(&ictx->lock);
+ if (ictx->pending) {
+ /*
+ * TBD: dequeue *all* non-conflicting
+ * reqs
+ *
+ * With the stub implementation there
+ * can only be one request active at a
+ * time (zero here) so it's not an
+ * issue. In a real implementation
+ * there might still be other active
+ * requests to check against, and
+ * multiple pending requests that could
+ * continue.
+ */
+ gf_msg_debug (this->name, 0,
+ "unblocking next request");
+ --(ictx->pending);
+ next = list_entry (ictx->pqueue.next,
+ jbr_local_t, qlinks);
+ list_del(&next->qlinks);
+ list_add_tail(&next->qlinks,
+ &ictx->aqueue);
+ call_resume(next->qstub);
+ } else {
+ --(ictx->active);
+ }
+ UNLOCK(&ictx->lock);
+ }
+ }
+
+ ret = 0;
+
+out:
+ return ret;
+}
+
+int32_t
+jbr_lk_complete (call_frame_t *frame, void *cookie, xlator_t *this,
+ int32_t op_ret, int32_t op_errno,
+ struct gf_flock *flock, dict_t *xdata)
+{
+ int32_t ret = -1;
+ jbr_private_t *priv = NULL;
+ jbr_local_t *local = NULL;
+ gf_boolean_t result = _gf_false;
+
+ 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);
+ local = frame->local;
+ GF_VALIDATE_OR_GOTO (this->name, local, err);
+ GF_VALIDATE_OR_GOTO (this->name, flock, err);
+ GF_VALIDATE_OR_GOTO (this->name, xdata, err);
+
+ /*
+ * Remove from queue for unlock operation only *
+ * For lock operation, it will be done in fan-in *
+ */
+ if (flock->l_type == F_UNLCK) {
+ ret = jbr_remove_from_queue (frame, this);
+ if (ret)
+ goto err;
+ }
+
+ /*
+ * On a follower, unwind with the op_ret and op_errno. On a *
+ * leader, if the fop is a locking fop, and its a failure, *
+ * send fail, else call stub which will dispatch the fop to *
+ * the followers. *
+ * *
+ * If the fop is a unlocking fop, check quorum. If quorum *
+ * is met, then send success. Else Rollback on leader, *
+ * followed by followers, and then send -ve ack to client. *
+ */
+ if (priv->leader) {
+
+ /* Increase the successful acks if it's a success. */
+ LOCK(&frame->lock);
+ if (op_ret != -1)
+ (local->successful_acks)++;
+ UNLOCK(&frame->lock);
+
+ if (flock->l_type == F_UNLCK) {
+ result = fop_quorum_check (this,
+ (double)priv->n_children,
+ (double)local->successful_acks);
+ 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.");
+
+ /* TODO: PERFORM UNLOCK ROLLBACK ON LEADER *
+ * FOLLOWED BY FOLLOWERS. */
+ } else {
+ op_ret = 0;
+ op_errno = 0;
+ }
+
+ fd_unref(local->fd);
+ STACK_UNWIND_STRICT (lk, frame, op_ret, op_errno,
+ flock, xdata);
+ } else {
+ if (op_ret == -1) {
+ gf_msg (this->name, GF_LOG_ERROR, 0,
+ J_MSG_LOCK_FAILURE,
+ "The lock operation failed on "
+ "the leader.");
+
+ fd_unref(local->fd);
+ STACK_UNWIND_STRICT (lk, frame, op_ret,
+ op_errno, flock, xdata);
+ } else {
+ if (!local->stub) {
+ goto err;
+ }
+
+ call_resume(local->stub);
+ }
+ }
+ } else {
+ fd_unref(local->fd);
+ STACK_UNWIND_STRICT (lk, frame, op_ret, op_errno,
+ flock, xdata);
+ }
+
+ return 0;
+
+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 (lk, frame, -1, op_errno,
+ flock, xdata);
+ return 0;
+}
+
+int32_t
+jbr_lk_fan_in (call_frame_t *frame, void *cookie, xlator_t *this,
+ int32_t op_ret, int32_t op_errno, struct gf_flock *flock,
+ dict_t *xdata)
+{
+ uint8_t call_count = -1;
+ int32_t ret = -1;
+ 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);
+
+ 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);
+
+ if (call_count == 0) {
+ /*
+ * If the fop is a locking fop, then check quorum. If quorum *
+ * is met, send successful ack to the client. If quorum is *
+ * not met, then rollback locking on followers, followed by *
+ * rollback of locking on leader, and then sending -ve ack *
+ * to the client. *
+ * *
+ * If the fop is a unlocking fop, then call stub. *
+ */
+ if (flock->l_type == F_UNLCK) {
+ call_resume(local->stub);
+ } else {
+ /*
+ * Remove from queue for locking fops, for unlocking *
+ * fops, it is taken care of in jbr_lk_complete *
+ */
+ ret = jbr_remove_from_queue (frame, this);
+ if (ret)
+ goto out;
+
+ fd_unref(local->fd);
+
+ result = fop_quorum_check (this,
+ (double)priv->n_children,
+ (double)local->successful_acks);
+ 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 locking "
+ "operation and initiating rollback on "
+ "followers and the leader "
+ "respectively.");
+
+ /* TODO: PERFORM ROLLBACK OF LOCKING ON
+ * FOLLOWERS, FOLLOWED BY ROLLBACK ON
+ * LEADER.
+ */
+
+ STACK_UNWIND_STRICT (lk, frame, -1, EROFS,
+ flock, xdata);
+ } else {
+ STACK_UNWIND_STRICT (lk, frame, 0, 0,
+ flock, xdata);
+ }
+ }
+ }
+
+ ret = 0;
+out:
+ return ret;
+}
+
+/*
+ * Called from leader for locking fop, being writen as a separate *
+ * function so as to support queues. *
+ */
+int32_t
+jbr_perform_lk_on_leader (call_frame_t *frame, xlator_t *this,
+ fd_t *fd, int32_t cmd, struct gf_flock *flock,
+ dict_t *xdata)
+{
+ 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, flock, out);
+ GF_VALIDATE_OR_GOTO (this->name, fd, out);
+
+ STACK_WIND (frame, jbr_lk_complete,
+ FIRST_CHILD(this), FIRST_CHILD(this)->fops->lk,
+ fd, cmd, flock, xdata);
+
+ ret = 0;
+out:
+ return ret;
+}
+
+int32_t
+jbr_lk_perform_local_op (call_frame_t *frame, xlator_t *this, int *op_errno,
+ fd_t *fd, int32_t cmd, struct gf_flock *flock,
+ dict_t *xdata)
+{
+ int32_t ret = -1;
+ jbr_local_t *local = NULL;
+
+ 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_VALIDATE_OR_GOTO (this->name, fd, out);
+ GF_VALIDATE_OR_GOTO (this->name, op_errno, out);
+ GF_VALIDATE_OR_GOTO (this->name, flock, out);
+
+ /*
+ * Check if the fop is a locking fop or unlocking fop, and
+ * handle it accordingly. If it is a locking fop, take the
+ * lock on leader first, and then send it to the followers.
+ * If it is a unlocking fop, unlock the followers first,
+ * and then on meeting quorum perform the unlock on the leader.
+ */
+ if (flock->l_type == F_UNLCK) {
+ ret = jbr_lk_call_dispatch (frame, this, op_errno,
+ fd, cmd, flock, xdata);
+ if (ret)
+ goto out;
+ } else {
+ 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");
+
+ local->qstub = fop_lk_stub (frame,
+ jbr_perform_lk_on_leader,
+ fd, cmd, flock, xdata);
+ 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);
+ ret = jbr_perform_lk_on_leader (frame, this, fd, cmd,
+ flock, xdata);
+ }
+
+ ret = 0;
+out:
+ return ret;
+}
+
+int32_t
+jbr_lk_continue (call_frame_t *frame, xlator_t *this,
+ fd_t *fd, int32_t cmd, struct gf_flock *flock, dict_t *xdata)
+{
+ int32_t ret = -1;
+ 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);
+ GF_VALIDATE_OR_GOTO (this->name, flock, out);
+ GF_VALIDATE_OR_GOTO (this->name, fd, out);
+ GF_VALIDATE_OR_GOTO (this->name, xdata, out);
+
+ /*
+ * If it's a locking fop, then call dispatch to followers *
+ * If it's a unlock fop, then perform the unlock operation *
+ */
+ if (flock->l_type == F_UNLCK) {
+ STACK_WIND (frame, jbr_lk_complete,
+ FIRST_CHILD(this), FIRST_CHILD(this)->fops->lk,
+ fd, cmd, flock, xdata);
+ } else {
+ /*
+ * Directly call jbr_lk_dispatch instead of appending *
+ * in queue, which is done at jbr_lk_perform_local_op *
+ * for locking fops *
+ */
+ ret = jbr_lk_dispatch (frame, this, fd, cmd,
+ flock, xdata);
+ if (ret) {
+ STACK_UNWIND_STRICT (lk, frame, -1, 0,
+ flock, xdata);
+ goto out;
+ }
+ }
+
+ ret = 0;
+out:
+ return ret;
+}
+
#pragma generate
uint8_t
generated by cgit (git 2.34.1) at 2024-11-17 03:21:21 +0000