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Diffstat (limited to 'src/librbd/operation/SnapshotRemoveRequest.cc')
| -rw-r--r-- | src/librbd/operation/SnapshotRemoveRequest.cc | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/src/librbd/operation/SnapshotRemoveRequest.cc b/src/librbd/operation/SnapshotRemoveRequest.cc new file mode 100644 index 000000000..b78be8a0a --- /dev/null +++ b/src/librbd/operation/SnapshotRemoveRequest.cc @@ -0,0 +1,505 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +// vim: ts=8 sw=2 smarttab + +#include "librbd/operation/SnapshotRemoveRequest.h" +#include "common/dout.h" +#include "common/errno.h" +#include "include/ceph_assert.h" +#include "cls/rbd/cls_rbd_client.h" +#include "librbd/ImageCtx.h" +#include "librbd/ObjectMap.h" +#include "librbd/Utils.h" +#include "librbd/image/DetachChildRequest.h" +#include "librbd/mirror/snapshot/RemoveImageStateRequest.h" + +#define dout_subsys ceph_subsys_rbd +#undef dout_prefix +#define dout_prefix *_dout << "librbd::SnapshotRemoveRequest: " << this << " " \ + << __func__ << ": " + +namespace librbd { +namespace operation { + +using util::create_context_callback; +using util::create_rados_callback; + +template <typename I> +SnapshotRemoveRequest<I>::SnapshotRemoveRequest( + I &image_ctx, Context *on_finish, + const cls::rbd::SnapshotNamespace &snap_namespace, + const std::string &snap_name, uint64_t snap_id) + : Request<I>(image_ctx, on_finish), m_snap_namespace(snap_namespace), + m_snap_name(snap_name), m_snap_id(snap_id) { +} + +template <typename I> +void SnapshotRemoveRequest<I>::send_op() { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + + ceph_assert(ceph_mutex_is_locked(image_ctx.owner_lock)); + { + std::shared_lock image_locker{image_ctx.image_lock}; + if (image_ctx.snap_info.find(m_snap_id) == image_ctx.snap_info.end()) { + lderr(cct) << "snapshot doesn't exist" << dendl; + this->async_complete(-ENOENT); + return; + } + } + + trash_snap(); +} + +template <typename I> +bool SnapshotRemoveRequest<I>::should_complete(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + if (r < 0 && r != -EBUSY) { + lderr(cct) << "encountered error: " << cpp_strerror(r) << dendl; + } + return true; +} + +template <typename I> +void SnapshotRemoveRequest<I>::trash_snap() { + I &image_ctx = this->m_image_ctx; + if (image_ctx.old_format) { + release_snap_id(); + return; + } else if (cls::rbd::get_snap_namespace_type(m_snap_namespace) == + cls::rbd::SNAPSHOT_NAMESPACE_TYPE_TRASH) { + get_snap(); + return; + } + + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << dendl; + + librados::ObjectWriteOperation op; + cls_client::snapshot_trash_add(&op, m_snap_id); + + auto aio_comp = create_rados_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_trash_snap>(this); + int r = image_ctx.md_ctx.aio_operate(image_ctx.header_oid, aio_comp, &op); + ceph_assert(r == 0); + aio_comp->release(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_trash_snap(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r == -EOPNOTSUPP) { + // trash / clone v2 not supported + detach_child(); + return; + } else if (r < 0 && r != -EEXIST) { + lderr(cct) << "failed to move snapshot to trash: " << cpp_strerror(r) + << dendl; + this->complete(r); + return; + } + + m_trashed_snapshot = true; + get_snap(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::get_snap() { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << dendl; + + librados::ObjectReadOperation op; + cls_client::snapshot_get_start(&op, m_snap_id); + + auto aio_comp = create_rados_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_get_snap>(this); + m_out_bl.clear(); + int r = image_ctx.md_ctx.aio_operate(image_ctx.header_oid, aio_comp, &op, + &m_out_bl); + ceph_assert(r == 0); + aio_comp->release(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_get_snap(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r == 0) { + cls::rbd::SnapshotInfo snap_info; + + auto it = m_out_bl.cbegin(); + r = cls_client::snapshot_get_finish(&it, &snap_info); + m_child_attached = (snap_info.child_count > 0); + if (r == 0 && m_child_attached) { + list_children(); + return; + } + } + + if (r < 0) { + lderr(cct) << "failed to retrieve snapshot: " << cpp_strerror(r) + << dendl; + this->complete(r); + return; + } + + detach_child(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::list_children() { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << dendl; + + librados::ObjectReadOperation op; + cls_client::children_list_start(&op, m_snap_id); + + m_out_bl.clear(); + m_child_images.clear(); + auto aio_comp = create_rados_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_list_children>(this); + int r = image_ctx.md_ctx.aio_operate(image_ctx.header_oid, aio_comp, &op, + &m_out_bl); + ceph_assert(r == 0); + aio_comp->release(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_list_children(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r == 0) { + auto it = m_out_bl.cbegin(); + r = cls_client::children_list_finish(&it, &m_child_images); + } + + if (r < 0 && r != -ENOENT) { + lderr(cct) << "failed to retrieve child: " << cpp_strerror(r) + << dendl; + this->complete(r); + return; + } + + detach_stale_child(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::detach_stale_child() { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << dendl; + + for (auto& child_image : m_child_images) { + m_child_attached = true; + IoCtx ioctx; + int r = util::create_ioctx(image_ctx.md_ctx, "child image", + child_image.pool_id, + child_image.pool_namespace, &ioctx); + if (r == -ENOENT) { + librados::ObjectWriteOperation op; + cls_client::child_detach(&op, m_snap_id, + {child_image.pool_id, + child_image.pool_namespace, + child_image.image_id}); + auto aio_comp = create_rados_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_detach_stale_child>(this); + r = image_ctx.md_ctx.aio_operate(image_ctx.header_oid, aio_comp, &op); + ceph_assert(r == 0); + aio_comp->release(); + return; + } else if (r < 0) { + this->async_complete(r); + return; + } + } + + detach_child(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_detach_stale_child(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r < 0 && r != -ENOENT) { + lderr(cct) << "failed to detach stale child: " << cpp_strerror(r) + << dendl; + this->complete(r); + return; + } + + m_child_attached = false; + list_children(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::detach_child() { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + + bool detach_child = false; + { + std::shared_lock image_locker{image_ctx.image_lock}; + + cls::rbd::ParentImageSpec our_pspec; + int r = image_ctx.get_parent_spec(m_snap_id, &our_pspec); + if (r < 0) { + if (r == -ENOENT) { + ldout(cct, 1) << "No such snapshot" << dendl; + } else { + lderr(cct) << "failed to retrieve parent spec" << dendl; + } + + this->async_complete(r); + return; + } + + if (image_ctx.parent_md.spec != our_pspec && + (scan_for_parents(our_pspec) == -ENOENT)) { + // no other references to the parent image + detach_child = true; + } + } + + if (!detach_child) { + // HEAD image or other snapshots still associated with parent + remove_object_map(); + return; + } + + ldout(cct, 5) << dendl; + auto ctx = create_context_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_detach_child>(this); + auto req = image::DetachChildRequest<I>::create(image_ctx, ctx); + req->send(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_detach_child(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r < 0 && r != -ENOENT) { + lderr(cct) << "failed to detach child from parent: " << cpp_strerror(r) + << dendl; + this->complete(r); + return; + } + + remove_object_map(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::remove_object_map() { + I &image_ctx = this->m_image_ctx; + if (m_child_attached) { + // if a clone v2 child is attached to this snapshot, we cannot + // proceed. It's only an error if the snap was already in the trash + this->complete(m_trashed_snapshot ? 0 : -EBUSY); + return; + } + + CephContext *cct = image_ctx.cct; + + { + std::shared_lock owner_lock{image_ctx.owner_lock}; + std::unique_lock image_locker{image_ctx.image_lock}; + if (image_ctx.object_map != nullptr) { + ldout(cct, 5) << dendl; + + auto ctx = create_context_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_remove_object_map>(this); + image_ctx.object_map->snapshot_remove(m_snap_id, ctx); + return; + } + } + + // object map disabled + remove_image_state(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_remove_object_map(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r < 0) { + lderr(cct) << "failed to remove snapshot object map: " << cpp_strerror(r) + << dendl; + this->complete(r); + return; + } + + remove_image_state(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::remove_image_state() { + I &image_ctx = this->m_image_ctx; + auto type = cls::rbd::get_snap_namespace_type(m_snap_namespace); + + if (type != cls::rbd::SNAPSHOT_NAMESPACE_TYPE_MIRROR) { + release_snap_id(); + return; + } + + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << dendl; + + auto ctx = create_context_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_remove_image_state>(this); + auto req = mirror::snapshot::RemoveImageStateRequest<I>::create( + &image_ctx, m_snap_id, ctx); + req->send(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_remove_image_state(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r < 0) { + lderr(cct) << "failed to remove image state: " << cpp_strerror(r) + << dendl; + if (r != -ENOENT) { + this->complete(r); + return; + } + } + + release_snap_id(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::release_snap_id() { + I &image_ctx = this->m_image_ctx; + + if (!image_ctx.data_ctx.is_valid()) { + remove_snap(); + return; + } + + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "snap_name=" << m_snap_name << ", " + << "snap_id=" << m_snap_id << dendl; + + auto aio_comp = create_rados_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_release_snap_id>(this); + image_ctx.data_ctx.aio_selfmanaged_snap_remove(m_snap_id, aio_comp); + aio_comp->release(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_release_snap_id(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r < 0 && r != -ENOENT) { + lderr(cct) << "failed to release snap id: " << cpp_strerror(r) << dendl; + this->complete(r); + return; + } + + remove_snap(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::remove_snap() { + I &image_ctx = this->m_image_ctx; + + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << dendl; + + librados::ObjectWriteOperation op; + if (image_ctx.old_format) { + cls_client::old_snapshot_remove(&op, m_snap_name); + } else { + cls_client::snapshot_remove(&op, m_snap_id); + } + + auto aio_comp = create_rados_callback< + SnapshotRemoveRequest<I>, + &SnapshotRemoveRequest<I>::handle_remove_snap>(this); + int r = image_ctx.md_ctx.aio_operate(image_ctx.header_oid, aio_comp, &op); + ceph_assert(r == 0); + aio_comp->release(); +} + +template <typename I> +void SnapshotRemoveRequest<I>::handle_remove_snap(int r) { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << "r=" << r << dendl; + + if (r < 0) { + lderr(cct) << "failed to remove snapshot: " << cpp_strerror(r) << dendl; + this->complete(r); + return; + } + + remove_snap_context(); + this->complete(0); +} + +template <typename I> +void SnapshotRemoveRequest<I>::remove_snap_context() { + I &image_ctx = this->m_image_ctx; + CephContext *cct = image_ctx.cct; + ldout(cct, 5) << dendl; + + std::unique_lock image_locker{image_ctx.image_lock}; + image_ctx.rm_snap(m_snap_namespace, m_snap_name, m_snap_id); +} + +template <typename I> +int SnapshotRemoveRequest<I>::scan_for_parents( + cls::rbd::ParentImageSpec &pspec) { + I &image_ctx = this->m_image_ctx; + ceph_assert(ceph_mutex_is_locked(image_ctx.image_lock)); + + if (pspec.pool_id != -1) { + map<uint64_t, SnapInfo>::iterator it; + for (it = image_ctx.snap_info.begin(); + it != image_ctx.snap_info.end(); ++it) { + // skip our snap id (if checking base image, CEPH_NOSNAP won't match) + if (it->first == m_snap_id) { + continue; + } + if (it->second.parent.spec == pspec) { + break; + } + } + if (it == image_ctx.snap_info.end()) { + return -ENOENT; + } + } + return 0; +} + +} // namespace operation +} // namespace librbd + +template class librbd::operation::SnapshotRemoveRequest<librbd::ImageCtx>; |