--- /dev/null
- last_read = images.rbegin()->first;
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+/** \file
+ *
+ * This is an OSD class that implements methods for
+ * use with rbd.
+ *
+ * Most of these deal with the rbd header object. Methods prefixed
+ * with old_ deal with the original rbd design, in which clients read
+ * and interpreted the header object directly.
+ *
+ * The new format is meant to be opaque to clients - all their
+ * interactions with non-data objects should go through this
+ * class. The OSD class interface leaves the class to implement its
+ * own argument and payload serialization/deserialization, so for ease
+ * of implementation we use the existing ceph encoding/decoding
+ * methods. Something like json might be preferable, but the rbd
+ * kernel module has to be able understand format as well. The
+ * datatypes exposed to the clients are strings, unsigned integers,
+ * and vectors of those types. The on-wire format can be found in
+ * src/include/encoding.h.
+ *
+ * The methods for interacting with the new format document their
+ * parameters as the client sees them - it would be silly to mention
+ * in each one that they take an input and an output bufferlist.
+ */
+
+#include <algorithm>
+#include <cstring>
+#include <cstdlib>
+#include <errno.h>
+#include <iostream>
+#include <map>
+#include <sstream>
+#include <vector>
+
+#include "include/types.h"
+#include "objclass/objclass.h"
+#include "include/rbd_types.h"
+
+#include "cls/rbd/cls_rbd.h"
+
+
+/*
+ * Object keys:
+ *
+ * <partial list>
+ *
+ * stripe_unit: size in bytes of the stripe unit. if not present,
+ * the stripe unit is assumed to match the object size (1 << order).
+ *
+ * stripe_count: number of objects to stripe over before looping back.
+ * if not present or 1, striping is disabled. this is the default.
+ *
+ */
+
+CLS_VER(2,0)
+CLS_NAME(rbd)
+
+cls_handle_t h_class;
+cls_method_handle_t h_create;
+cls_method_handle_t h_get_features;
+cls_method_handle_t h_get_size;
+cls_method_handle_t h_set_size;
+cls_method_handle_t h_get_parent;
+cls_method_handle_t h_set_parent;
+cls_method_handle_t h_get_protection_status;
+cls_method_handle_t h_set_protection_status;
+cls_method_handle_t h_get_stripe_unit_count;
+cls_method_handle_t h_set_stripe_unit_count;
+cls_method_handle_t h_remove_parent;
+cls_method_handle_t h_add_child;
+cls_method_handle_t h_remove_child;
+cls_method_handle_t h_get_children;
+cls_method_handle_t h_get_snapcontext;
+cls_method_handle_t h_get_object_prefix;
+cls_method_handle_t h_get_snapshot_name;
+cls_method_handle_t h_snapshot_add;
+cls_method_handle_t h_snapshot_remove;
+cls_method_handle_t h_get_all_features;
+cls_method_handle_t h_copyup;
+cls_method_handle_t h_get_id;
+cls_method_handle_t h_set_id;
+cls_method_handle_t h_dir_get_id;
+cls_method_handle_t h_dir_get_name;
+cls_method_handle_t h_dir_list;
+cls_method_handle_t h_dir_add_image;
+cls_method_handle_t h_dir_remove_image;
+cls_method_handle_t h_dir_rename_image;
+cls_method_handle_t h_old_snapshots_list;
+cls_method_handle_t h_old_snapshot_add;
+cls_method_handle_t h_old_snapshot_remove;
+cls_method_handle_t h_assign_bid;
+
+#define RBD_MAX_KEYS_READ 64
+#define RBD_SNAP_KEY_PREFIX "snapshot_"
+#define RBD_DIR_ID_KEY_PREFIX "id_"
+#define RBD_DIR_NAME_KEY_PREFIX "name_"
+
+static int snap_read_header(cls_method_context_t hctx, bufferlist& bl)
+{
+ unsigned snap_count = 0;
+ uint64_t snap_names_len = 0;
+ int rc;
+ struct rbd_obj_header_ondisk *header;
+
+ CLS_LOG(20, "snapshots_list");
+
+ while (1) {
+ int len = sizeof(*header) +
+ snap_count * sizeof(struct rbd_obj_snap_ondisk) +
+ snap_names_len;
+
+ rc = cls_cxx_read(hctx, 0, len, &bl);
+ if (rc < 0)
+ return rc;
+
+ header = (struct rbd_obj_header_ondisk *)bl.c_str();
+
+ if ((snap_count != header->snap_count) ||
+ (snap_names_len != header->snap_names_len)) {
+ snap_count = header->snap_count;
+ snap_names_len = header->snap_names_len;
+ bl.clear();
+ continue;
+ }
+ break;
+ }
+
+ return 0;
+}
+
+static void key_from_snap_id(snapid_t snap_id, string *out)
+{
+ ostringstream oss;
+ oss << RBD_SNAP_KEY_PREFIX
+ << std::setw(16) << std::setfill('0') << std::hex << snap_id;
+ *out = oss.str();
+}
+
+static snapid_t snap_id_from_key(const string &key)
+{
+ istringstream iss(key);
+ uint64_t id;
+ iss.ignore(strlen(RBD_SNAP_KEY_PREFIX)) >> std::hex >> id;
+ return id;
+}
+
+template<typename T>
+static int read_key(cls_method_context_t hctx, const string &key, T *out)
+{
+ bufferlist bl;
+ int r = cls_cxx_map_get_val(hctx, key, &bl);
+ if (r < 0) {
+ if (r != -ENOENT) {
+ CLS_ERR("error reading omap key %s: %d", key.c_str(), r);
+ }
+ return r;
+ }
+
+ try {
+ bufferlist::iterator it = bl.begin();
+ ::decode(*out, it);
+ } catch (const buffer::error &err) {
+ CLS_ERR("error decoding %s", key.c_str());
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static bool is_valid_id(const string &id) {
+ if (!id.size())
+ return false;
+ for (size_t i = 0; i < id.size(); ++i) {
+ if (!isalnum(id[i])) {
+ return false;
+ }
+ }
+ return true;
+}
+
+/**
+ * Initialize the header with basic metadata.
+ * Extra features may initialize more fields in the future.
+ * Everything is stored as key/value pairs as omaps in the header object.
+ *
+ * If features the OSD does not understand are requested, -ENOSYS is
+ * returned.
+ *
+ * Input:
+ * @param size number of bytes in the image (uint64_t)
+ * @param order bits to shift to determine the size of data objects (uint8_t)
+ * @param features what optional things this image will use (uint64_t)
+ * @param object_prefix a prefix for all the data objects
+ *
+ * Output:
+ * @return 0 on success, negative error code on failure
+ */
+int create(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ string object_prefix;
+ uint64_t features, size;
+ uint8_t order;
+
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(size, iter);
+ ::decode(order, iter);
+ ::decode(features, iter);
+ ::decode(object_prefix, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "create object_prefix=%s size=%llu order=%u features=%llu",
+ object_prefix.c_str(), size, order, features);
+
+ if (features & ~RBD_FEATURES_ALL) {
+ return -ENOSYS;
+ }
+
+ if (!object_prefix.size()) {
+ return -EINVAL;
+ }
+
+ bufferlist stored_prefixbl;
+ int r = cls_cxx_map_get_val(hctx, "object_prefix", &stored_prefixbl);
+ if (r != -ENOENT) {
+ CLS_ERR("reading object_prefix returned %d", r);
+ return -EEXIST;
+ }
+
+ bufferlist sizebl;
+ ::encode(size, sizebl);
+ r = cls_cxx_map_set_val(hctx, "size", &sizebl);
+ if (r < 0)
+ return r;
+
+ bufferlist orderbl;
+ ::encode(order, orderbl);
+ r = cls_cxx_map_set_val(hctx, "order", &orderbl);
+ if (r < 0)
+ return r;
+
+ bufferlist featuresbl;
+ ::encode(features, featuresbl);
+ r = cls_cxx_map_set_val(hctx, "features", &featuresbl);
+ if (r < 0)
+ return r;
+
+ bufferlist object_prefixbl;
+ ::encode(object_prefix, object_prefixbl);
+ r = cls_cxx_map_set_val(hctx, "object_prefix", &object_prefixbl);
+ if (r < 0)
+ return r;
+
+ bufferlist snap_seqbl;
+ uint64_t snap_seq = 0;
+ ::encode(snap_seq, snap_seqbl);
+ r = cls_cxx_map_set_val(hctx, "snap_seq", &snap_seqbl);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+/**
+ * Input:
+ * @param snap_id which snapshot to query, or CEPH_NOSNAP (uint64_t)
+ *
+ * Output:
+ * @param features list of enabled features for the given snapshot (uint64_t)
+ * @returns 0 on success, negative error code on failure
+ */
+int get_features(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ uint64_t features, snap_id;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(snap_id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "get_features snap_id=%llu", snap_id);
+
+ if (snap_id == CEPH_NOSNAP) {
+ int r = read_key(hctx, "features", &features);
+ if (r < 0) {
+ CLS_ERR("failed to read features off disk: %s", strerror(r));
+ return r;
+ }
+ } else {
+ cls_rbd_snap snap;
+ string snapshot_key;
+ key_from_snap_id(snap_id, &snapshot_key);
+ int r = read_key(hctx, snapshot_key, &snap);
+ if (r < 0)
+ return r;
+
+ features = snap.features;
+ }
+
+ uint64_t incompatible = features & RBD_FEATURES_INCOMPATIBLE;
+ ::encode(features, *out);
+ ::encode(incompatible, *out);
+
+ return 0;
+}
+
+/**
+ * check that given feature(s) are set
+ *
+ * @param hctx context
+ * @param need features needed
+ * @return 0 if features are set, negative error (like ENOEXEC) otherwise
+ */
+int require_feature(cls_method_context_t hctx, uint64_t need)
+{
+ uint64_t features;
+ int r = read_key(hctx, "features", &features);
+ if (r == -ENOENT) // this implies it's an old-style image with no features
+ return -ENOEXEC;
+ if (r < 0)
+ return r;
+ if ((features & need) != need) {
+ CLS_LOG(10, "require_feature missing feature %llx, have %llx", need, features);
+ return -ENOEXEC;
+ }
+ return 0;
+}
+
+/**
+ * Input:
+ * @param snap_id which snapshot to query, or CEPH_NOSNAP (uint64_t)
+ *
+ * Output:
+ * @param order bits to shift to get the size of data objects (uint8_t)
+ * @param size size of the image in bytes for the given snapshot (uint64_t)
+ * @returns 0 on success, negative error code on failure
+ */
+int get_size(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ uint64_t snap_id, size;
+ uint8_t order;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(snap_id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "get_size snap_id=%llu", snap_id);
+
+ int r = read_key(hctx, "order", &order);
+ if (r < 0) {
+ CLS_ERR("failed to read the order off of disk: %s", strerror(r));
+ return r;
+ }
+
+ if (snap_id == CEPH_NOSNAP) {
+ r = read_key(hctx, "size", &size);
+ if (r < 0) {
+ CLS_ERR("failed to read the image's size off of disk: %s", strerror(r));
+ return r;
+ }
+ } else {
+ cls_rbd_snap snap;
+ string snapshot_key;
+ key_from_snap_id(snap_id, &snapshot_key);
+ int r = read_key(hctx, snapshot_key, &snap);
+ if (r < 0)
+ return r;
+
+ size = snap.image_size;
+ }
+
+ ::encode(order, *out);
+ ::encode(size, *out);
+
+ return 0;
+}
+
+/**
+ * Input:
+ * @param size new capacity of the image in bytes (uint64_t)
+ *
+ * Output:
+ * @returns 0 on success, negative error code on failure
+ */
+int set_size(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ uint64_t size;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(size, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ // check that size exists to make sure this is a header object
+ // that was created correctly
+ uint64_t orig_size;
+ int r = read_key(hctx, "size", &orig_size);
+ if (r < 0) {
+ CLS_ERR("Could not read image's size off disk: %s", strerror(r));
+ return r;
+ }
+
+ CLS_LOG(20, "set_size size=%llu orig_size=%llu", size);
+
+ bufferlist sizebl;
+ ::encode(size, sizebl);
+ r = cls_cxx_map_set_val(hctx, "size", &sizebl);
+ if (r < 0) {
+ CLS_ERR("error writing snapshot metadata: %d", r);
+ return r;
+ }
+
+ // if we are shrinking, and have a parent, shrink our overlap with
+ // the parent, too.
+ if (size < orig_size) {
+ cls_rbd_parent parent;
+ r = read_key(hctx, "parent", &parent);
+ if (r == -ENOENT)
+ r = 0;
+ if (r < 0)
+ return r;
+ if (parent.exists() && parent.overlap > size) {
+ bufferlist parentbl;
+ parent.overlap = size;
+ ::encode(parent, parentbl);
+ r = cls_cxx_map_set_val(hctx, "parent", &parentbl);
+ if (r < 0) {
+ CLS_ERR("error writing parent: %d", r);
+ return r;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * verify that the header object exists
+ *
+ * @return 0 if the object exists, -ENOENT if it does not, or other error
+ */
+int check_exists(cls_method_context_t hctx)
+{
+ uint64_t size;
+ time_t mtime;
+ return cls_cxx_stat(hctx, &size, &mtime);
+}
+
+/**
+ * get the current protection status of the specified snapshot
+ *
+ * Input:
+ * @param snap_id (uint64_t) which snapshot to get the status of
+ *
+ * Output:
+ * @param status (uint8_t) one of:
+ * RBD_PROTECTION_STATUS_{PROTECTED, UNPROTECTED, UNPROTECTING}
+ *
+ * @returns 0 on success, negative error code on failure
+ * @returns -EINVAL if snapid is CEPH_NOSNAP
+ */
+int get_protection_status(cls_method_context_t hctx, bufferlist *in,
+ bufferlist *out)
+{
+ snapid_t snap_id;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(snap_id, iter);
+ } catch (const buffer::error &err) {
+ CLS_LOG(20, "get_protection_status: invalid decode");
+ return -EINVAL;
+ }
+
+ int r = check_exists(hctx);
+ if (r < 0)
+ return r;
+
+ CLS_LOG(20, "get_protection_status snap_id=%llu", snap_id.val);
+
+ if (snap_id == CEPH_NOSNAP)
+ return -EINVAL;
+
+ cls_rbd_snap snap;
+ string snapshot_key;
+ key_from_snap_id(snap_id.val, &snapshot_key);
+ r = read_key(hctx, snapshot_key, &snap);
+ if (r < 0) {
+ CLS_ERR("could not read key for snapshot id %llu", snap_id.val);
+ return r;
+ }
+
+ if (snap.protection_status >= RBD_PROTECTION_STATUS_LAST) {
+ CLS_ERR("invalid protection status for snap id %llu: %u",
+ snap_id.val, snap.protection_status);
+ return -EIO;
+ }
+
+ ::encode(snap.protection_status, *out);
+ return 0;
+}
+
+/**
+ * set the proctection status of a snapshot
+ *
+ * Input:
+ * @param snapid (uint64_t) which snapshot to set the status of
+ * @param status (uint8_t) one of:
+ * RBD_PROTECTION_STATUS_{PROTECTED, UNPROTECTED, UNPROTECTING}
+ *
+ * @returns 0 on success, negative error code on failure
+ * @returns -EINVAL if snapid is CEPH_NOSNAP
+ */
+int set_protection_status(cls_method_context_t hctx, bufferlist *in,
+ bufferlist *out)
+{
+ snapid_t snap_id;
+ uint8_t status;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(snap_id, iter);
+ ::decode(status, iter);
+ } catch (const buffer::error &err) {
+ CLS_LOG(20, "set_protection_status: invalid decode");
+ return -EINVAL;
+ }
+
+ int r = check_exists(hctx);
+ if (r < 0)
+ return r;
+
+ r = require_feature(hctx, RBD_FEATURE_LAYERING);
+ if (r < 0) {
+ CLS_LOG(20, "image does not support layering");
+ return r;
+ }
+
+ CLS_LOG(20, "set_protection_status snapid=%llu status=%u",
+ snap_id.val, status);
+
+ if (snap_id == CEPH_NOSNAP)
+ return -EINVAL;
+
+ if (status >= RBD_PROTECTION_STATUS_LAST) {
+ CLS_LOG(10, "invalid protection status for snap id %llu: %u",
+ snap_id.val, status);
+ return -EINVAL;
+ }
+
+ cls_rbd_snap snap;
+ string snapshot_key;
+ key_from_snap_id(snap_id.val, &snapshot_key);
+ r = read_key(hctx, snapshot_key, &snap);
+ if (r < 0) {
+ CLS_ERR("could not read key for snapshot id %d", snap_id.val);
+ return r;
+ }
+
+ snap.protection_status = status;
+ bufferlist snapshot_bl;
+ ::encode(snap, snapshot_bl);
+ r = cls_cxx_map_set_val(hctx, snapshot_key, &snapshot_bl);
+ if (r < 0) {
+ CLS_ERR("error writing snapshot metadata: %d", r);
+ return r;
+ }
+
+ return 0;
+}
+
+/**
+ * get striping parameters
+ *
+ * Input:
+ * none
+ *
+ * Output:
+ * @param stripe unit (bytes)
+ * @param stripe count (num objects)
+ *
+ * @returns 0 on success
+ */
+int get_stripe_unit_count(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ int r = check_exists(hctx);
+ if (r < 0)
+ return r;
+
+ CLS_LOG(20, "get_stripe_unit_count");
+
+ r = require_feature(hctx, RBD_FEATURE_STRIPINGV2);
+ if (r < 0)
+ return r;
+
+ uint64_t stripe_unit = 0, stripe_count = 0;
+ r = read_key(hctx, "stripe_unit", &stripe_unit);
+ if (r == -ENOENT) {
+ // default to object size
+ uint8_t order;
+ r = read_key(hctx, "order", &order);
+ if (r < 0) {
+ CLS_ERR("failed to read the order off of disk: %s", strerror(r));
+ return -EIO;
+ }
+ stripe_unit = 1ull << order;
+ }
+ if (r < 0)
+ return r;
+ r = read_key(hctx, "stripe_count", &stripe_count);
+ if (r == -ENOENT) {
+ // default to 1
+ stripe_count = 1;
+ r = 0;
+ }
+ if (r < 0)
+ return r;
+
+ ::encode(stripe_unit, *out);
+ ::encode(stripe_count, *out);
+ return 0;
+}
+
+/**
+ * set striping parameters
+ *
+ * Input:
+ * @param stripe unit (bytes)
+ * @param stripe count (num objects)
+ *
+ * @returns 0 on success
+ */
+int set_stripe_unit_count(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ uint64_t stripe_unit, stripe_count;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(stripe_unit, iter);
+ ::decode(stripe_count, iter);
+ } catch (const buffer::error &err) {
+ CLS_LOG(20, "set_stripe_unit_count: invalid decode");
+ return -EINVAL;
+ }
+
+ if (!stripe_count || !stripe_unit)
+ return -EINVAL;
+
+ int r = check_exists(hctx);
+ if (r < 0)
+ return r;
+
+ CLS_LOG(20, "set_stripe_unit_count");
+
+ r = require_feature(hctx, RBD_FEATURE_STRIPINGV2);
+ if (r < 0)
+ return r;
+
+ uint8_t order;
+ r = read_key(hctx, "order", &order);
+ if (r < 0) {
+ CLS_ERR("failed to read the order off of disk: %s", strerror(r));
+ return r;
+ }
+ if ((1ull << order) % stripe_unit) {
+ CLS_ERR("stripe unit %lld is not a factor of the object size %lld", stripe_unit, 1ull << order);
+ return -EINVAL;
+ }
+
+ bufferlist bl, bl2;
+ ::encode(stripe_unit, bl);
+ r = cls_cxx_map_set_val(hctx, "stripe_unit", &bl);
+ if (r < 0) {
+ CLS_ERR("error writing stripe_unit metadata: %d", r);
+ return r;
+ }
+
+ ::encode(stripe_count, bl2);
+ r = cls_cxx_map_set_val(hctx, "stripe_count", &bl2);
+ if (r < 0) {
+ CLS_ERR("error writing stripe_count metadata: %d", r);
+ return r;
+ }
+
+ return 0;
+}
+
+
+/**
+ * get the current parent, if any
+ *
+ * Input:
+ * @param snap_id which snapshot to query, or CEPH_NOSNAP (uint64_t)
+ *
+ * Output:
+ * @param pool parent pool id (-1 if parent does not exist)
+ * @param image parent image id
+ * @param snapid parent snapid
+ * @param size portion of parent mapped under the child
+ *
+ * @returns 0 on success or parent does not exist, negative error code on failure
+ */
+int get_parent(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ uint64_t snap_id;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(snap_id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ int r = check_exists(hctx);
+ if (r < 0)
+ return r;
+
+ CLS_LOG(20, "get_parent snap_id=%llu", snap_id);
+
+ cls_rbd_parent parent;
+ r = require_feature(hctx, RBD_FEATURE_LAYERING);
+ if (r == 0) {
+ if (snap_id == CEPH_NOSNAP) {
+ r = read_key(hctx, "parent", &parent);
+ if (r < 0 && r != -ENOENT)
+ return r;
+ } else {
+ cls_rbd_snap snap;
+ string snapshot_key;
+ key_from_snap_id(snap_id, &snapshot_key);
+ r = read_key(hctx, snapshot_key, &snap);
+ if (r < 0 && r != -ENOENT)
+ return r;
+ parent = snap.parent;
+ }
+ }
+
+ ::encode(parent.pool, *out);
+ ::encode(parent.id, *out);
+ ::encode(parent.snapid, *out);
+ ::encode(parent.overlap, *out);
+ return 0;
+}
+
+/**
+ * set the image parent
+ *
+ * Input:
+ * @param pool parent pool
+ * @param id parent image id
+ * @param snapid parent snapid
+ * @param size parent size
+ *
+ * @returns 0 on success, or negative error code
+ */
+int set_parent(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ int64_t pool;
+ string id;
+ snapid_t snapid;
+ uint64_t size;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(pool, iter);
+ ::decode(id, iter);
+ ::decode(snapid, iter);
+ ::decode(size, iter);
+ } catch (const buffer::error &err) {
+ CLS_LOG(20, "cls_rbd::set_parent: invalid decode");
+ return -EINVAL;
+ }
+
+ int r = check_exists(hctx);
+ if (r < 0) {
+ CLS_LOG(20, "cls_rbd::set_parent: child already exists");
+ return r;
+ }
+
+ r = require_feature(hctx, RBD_FEATURE_LAYERING);
+ if (r < 0) {
+ CLS_LOG(20, "cls_rbd::set_parent: child does not support layering");
+ return r;
+ }
+
+ CLS_LOG(20, "set_parent pool=%lld id=%s snapid=%llu size=%llu",
+ pool, id.c_str(), snapid.val, size);
+
+ if (pool < 0 || id.length() == 0 || snapid == CEPH_NOSNAP || size == 0) {
+ return -EINVAL;
+ }
+
+ // make sure there isn't already a parent
+ cls_rbd_parent parent;
+ r = read_key(hctx, "parent", &parent);
+ if (r == 0) {
+ CLS_LOG(20, "set_parent existing parent pool=%lld id=%s snapid=%llu overlap=%llu",
+ parent.pool, parent.id.c_str(), parent.snapid.val,
+ parent.overlap);
+ return -EEXIST;
+ }
+
+ // our overlap is the min of our size and the parent's size.
+ uint64_t our_size;
+ r = read_key(hctx, "size", &our_size);
+ if (r < 0)
+ return r;
+
+ bufferlist parentbl;
+ parent.pool = pool;
+ parent.id = id;
+ parent.snapid = snapid;
+ parent.overlap = MIN(our_size, size);
+ ::encode(parent, parentbl);
+ r = cls_cxx_map_set_val(hctx, "parent", &parentbl);
+ if (r < 0) {
+ CLS_ERR("error writing parent: %d", r);
+ return r;
+ }
+
+ return 0;
+}
+
+
+/**
+ * remove the parent pointer
+ *
+ * This can only happen on the head, not on a snapshot. No arguments.
+ *
+ * @returns 0 on success, negative error code on failure.
+ */
+int remove_parent(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ int r = check_exists(hctx);
+ if (r < 0)
+ return r;
+
+ r = require_feature(hctx, RBD_FEATURE_LAYERING);
+ if (r < 0)
+ return r;
+
+ cls_rbd_parent parent;
+ r = read_key(hctx, "parent", &parent);
+ if (r < 0)
+ return r;
+
+ r = cls_cxx_map_remove_key(hctx, "parent");
+ if (r < 0) {
+ CLS_ERR("error removing parent: %d", r);
+ return r;
+ }
+
+ return 0;
+}
+
+/**
+ * methods for dealing with rbd_children object
+ */
+
+static int decode_parent_common(bufferlist::iterator& it, uint64_t *pool_id,
+ string *image_id, snapid_t *snap_id)
+{
+ try {
+ ::decode(*pool_id, it);
+ ::decode(*image_id, it);
+ ::decode(*snap_id, it);
+ } catch (const buffer::error &err) {
+ CLS_ERR("error decoding parent spec");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int decode_parent(bufferlist *in, uint64_t *pool_id,
+ string *image_id, snapid_t *snap_id)
+{
+ bufferlist::iterator it = in->begin();
+ return decode_parent_common(it, pool_id, image_id, snap_id);
+}
+
+static int decode_parent_and_child(bufferlist *in, uint64_t *pool_id,
+ string *image_id, snapid_t *snap_id,
+ string *c_image_id)
+{
+ bufferlist::iterator it = in->begin();
+ int r = decode_parent_common(it, pool_id, image_id, snap_id);
+ if (r < 0)
+ return r;
+ try {
+ ::decode(*c_image_id, it);
+ } catch (const buffer::error &err) {
+ CLS_ERR("error decoding child image id");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static string parent_key(uint64_t pool_id, string image_id, snapid_t snap_id)
+{
+ bufferlist key_bl;
+ ::encode(pool_id, key_bl);
+ ::encode(image_id, key_bl);
+ ::encode(snap_id, key_bl);
+ return string(key_bl.c_str(), key_bl.length());
+}
+
+/**
+ * add child to rbd_children directory object
+ *
+ * rbd_children is a map of (p_pool_id, p_image_id, p_snap_id) to
+ * [c_image_id, [c_image_id ... ]]
+ *
+ * Input:
+ * @param p_pool_id parent pool id
+ * @param p_image_id parent image oid
+ * @param p_snap_id parent snapshot id
+ * @param c_image_id new child image oid to add
+ *
+ * @returns 0 on success, negative error on failure
+ */
+
+int add_child(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ int r;
+
+ uint64_t p_pool_id;
+ snapid_t p_snap_id;
+ string p_image_id, c_image_id;
+ // Use set for ease of erase() for remove_child()
+ std::set<string> children;
+
+ r = decode_parent_and_child(in, &p_pool_id, &p_image_id, &p_snap_id,
+ &c_image_id);
+ if (r < 0)
+ return r;
+
+ CLS_LOG(20, "add_child %s to (%d, %s, %d)", c_image_id.c_str(),
+ p_pool_id, p_image_id.c_str(), p_snap_id.val);
+
+ string key = parent_key(p_pool_id, p_image_id, p_snap_id);
+
+ // get current child list for parent, if any
+ r = read_key(hctx, key, &children);
+ if ((r < 0) && (r != -ENOENT)) {
+ CLS_LOG(20, "add_child: omap read failed: %d", r);
+ return r;
+ }
+
+ if (children.find(c_image_id) != children.end()) {
+ CLS_LOG(20, "add_child: child already exists: %s", c_image_id.c_str());
+ return -EEXIST;
+ }
+ // add new child
+ children.insert(c_image_id);
+
+ // write back
+ bufferlist childbl;
+ ::encode(children, childbl);
+ r = cls_cxx_map_set_val(hctx, key, &childbl);
+ if (r < 0)
+ CLS_LOG(20, "add_child: omap write failed: %d", r);
+ return r;
+}
+
+/**
+ * remove child from rbd_children directory object
+ *
+ * Input:
+ * @param p_pool_id parent pool id
+ * @param p_image_id parent image oid
+ * @param p_snap_id parent snapshot id
+ * @param c_image_id new child image oid to add
+ *
+ * @returns 0 on success, negative error on failure
+ */
+
+int remove_child(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ int r;
+
+ uint64_t p_pool_id;
+ snapid_t p_snap_id;
+ string p_image_id, c_image_id;
+ std::set<string> children;
+
+ r = decode_parent_and_child(in, &p_pool_id, &p_image_id, &p_snap_id,
+ &c_image_id);
+ if (r < 0)
+ return r;
+
+ CLS_LOG(20, "remove_child %s from (%d, %s, %d)", c_image_id.c_str(),
+ p_pool_id, p_image_id.c_str(), p_snap_id.val);
+
+ string key = parent_key(p_pool_id, p_image_id, p_snap_id);
+
+ // get current child list for parent. Unlike add_child(), an empty list
+ // is an error (how can we remove something that doesn't exist?)
+ r = read_key(hctx, key, &children);
+ if (r < 0) {
+ CLS_LOG(20, "remove_child: read omap failed: %d", r);
+ return r;
+ }
+
+ if (children.find(c_image_id) == children.end()) {
+ CLS_LOG(20, "remove_child: child not found: %s", c_image_id.c_str());
+ return -ENOENT;
+ }
+ // find and remove child
+ children.erase(c_image_id);
+
+ // now empty? remove key altogether
+ if (children.empty()) {
+ r = cls_cxx_map_remove_key(hctx, key);
+ if (r < 0)
+ CLS_LOG(20, "remove_child: remove key failed: %d", r);
+ } else {
+ // write back shortened children list
+ bufferlist childbl;
+ ::encode(children, childbl);
+ r = cls_cxx_map_set_val(hctx, key, &childbl);
+ if (r < 0)
+ CLS_LOG(20, "remove_child: write omap failed: %d ", r);
+ }
+ return r;
+}
+
+/**
+ * Input:
+ * @param p_pool_id parent pool id
+ * @param p_image_id parent image oid
+ * @param p_snap_id parent snapshot id
+ * @param c_image_id new child image oid to add
+ *
+ * Output:
+ * @param children set<string> of children
+ *
+ * @returns 0 on success, negative error on failure
+ */
+int get_children(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ int r;
+ uint64_t p_pool_id;
+ snapid_t p_snap_id;
+ string p_image_id;
+ std::set<string> children;
+
+ r = decode_parent(in, &p_pool_id, &p_image_id, &p_snap_id);
+ if (r < 0)
+ return r;
+
+ CLS_LOG(20, "get_children of (%d, %s, %d)",
+ p_pool_id, p_image_id.c_str(), p_snap_id.val);
+
+ string key = parent_key(p_pool_id, p_image_id, p_snap_id);
+
+ r = read_key(hctx, key, &children);
+ if (r < 0) {
+ if (r != -ENOENT)
+ CLS_LOG(20, "get_children: read omap failed: %d", r);
+ return r;
+ }
+ ::encode(children, *out);
+ return 0;
+}
+
+
+/**
+ * Get the information needed to create a rados snap context for doing
+ * I/O to the data objects. This must include all snapshots.
+ *
+ * Output:
+ * @param snap_seq the highest snapshot id ever associated with the image (uint64_t)
+ * @param snap_ids existing snapshot ids in descending order (vector<uint64_t>)
+ * @returns 0 on success, negative error code on failure
+ */
+int get_snapcontext(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ CLS_LOG(20, "get_snapcontext");
+
+ int r;
+ int max_read = RBD_MAX_KEYS_READ;
+ vector<snapid_t> snap_ids;
+ string last_read = RBD_SNAP_KEY_PREFIX;
+
+ do {
+ set<string> keys;
+ r = cls_cxx_map_get_keys(hctx, last_read, max_read, &keys);
+ if (r < 0)
+ return r;
+
+ for (set<string>::const_iterator it = keys.begin();
+ it != keys.end(); ++it) {
+ if ((*it).find(RBD_SNAP_KEY_PREFIX) != 0)
+ break;
+ snapid_t snap_id = snap_id_from_key(*it);
+ snap_ids.push_back(snap_id);
+ }
+ if (keys.size() > 0)
+ last_read = *(keys.rbegin());
+ } while (r == max_read);
+
+ uint64_t snap_seq;
+ r = read_key(hctx, "snap_seq", &snap_seq);
+ if (r < 0) {
+ CLS_ERR("could not read the image's snap_seq off disk: %s", strerror(r));
+ return r;
+ }
+
+ // snap_ids must be descending in a snap context
+ std::reverse(snap_ids.begin(), snap_ids.end());
+
+ ::encode(snap_seq, *out);
+ ::encode(snap_ids, *out);
+
+ return 0;
+}
+
+/**
+ * Output:
+ * @param object_prefix prefix for data object names (string)
+ * @returns 0 on success, negative error code on failure
+ */
+int get_object_prefix(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ CLS_LOG(20, "get_object_prefix");
+
+ string object_prefix;
+ int r = read_key(hctx, "object_prefix", &object_prefix);
+ if (r < 0) {
+ CLS_ERR("failed to read the image's object prefix off of disk: %s",
+ strerror(r));
+ return r;
+ }
+
+ ::encode(object_prefix, *out);
+
+ return 0;
+}
+
+int get_snapshot_name(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ uint64_t snap_id;
+
+ bufferlist::iterator iter = in->begin();
+ try {
+ ::decode(snap_id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "get_snapshot_name snap_id=%llu", snap_id);
+
+ if (snap_id == CEPH_NOSNAP)
+ return -EINVAL;
+
+ cls_rbd_snap snap;
+ string snapshot_key;
+ key_from_snap_id(snap_id, &snapshot_key);
+ int r = read_key(hctx, snapshot_key, &snap);
+ if (r < 0)
+ return r;
+
+ ::encode(snap.name, *out);
+
+ return 0;
+}
+
+/**
+ * Adds a snapshot to an rbd header. Ensures the id and name are unique.
+ *
+ * Input:
+ * @param snap_name name of the snapshot (string)
+ * @param snap_id id of the snapshot (uint64_t)
+ *
+ * Output:
+ * @returns 0 on success, negative error code on failure.
+ * @returns -ESTALE if the input snap_id is less than the image's snap_seq
+ * @returns -EEXIST if the id or name are already used by another snapshot
+ */
+int snapshot_add(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ bufferlist snap_namebl, snap_idbl;
+ cls_rbd_snap snap_meta;
+
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(snap_meta.name, iter);
+ ::decode(snap_meta.id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "snapshot_add name=%s id=%llu", snap_meta.name.c_str(), snap_meta.id.val);
+
+ if (snap_meta.id > CEPH_MAXSNAP)
+ return -EINVAL;
+
+ uint64_t cur_snap_seq;
+ int r = read_key(hctx, "snap_seq", &cur_snap_seq);
+ if (r < 0) {
+ CLS_ERR("Could not read image's snap_seq off disk: %s", strerror(r));
+ return r;
+ }
+
+ // client lost a race with another snapshot creation.
+ // snap_seq must be monotonically increasing.
+ if (snap_meta.id < cur_snap_seq)
+ return -ESTALE;
+
+ r = read_key(hctx, "size", &snap_meta.image_size);
+ if (r < 0) {
+ CLS_ERR("Could not read image's size off disk: %s", strerror(r));
+ return r;
+ }
+ r = read_key(hctx, "features", &snap_meta.features);
+ if (r < 0) {
+ CLS_ERR("Could not read image's features off disk: %s", strerror(r));
+ return r;
+ }
+
+ int max_read = RBD_MAX_KEYS_READ;
+ string last_read = RBD_SNAP_KEY_PREFIX;
+ do {
+ map<string, bufferlist> vals;
+ r = cls_cxx_map_get_vals(hctx, last_read, RBD_SNAP_KEY_PREFIX,
+ max_read, &vals);
+ if (r < 0)
+ return r;
+
+ for (map<string, bufferlist>::iterator it = vals.begin();
+ it != vals.end(); ++it) {
+ cls_rbd_snap old_meta;
+ bufferlist::iterator iter = it->second.begin();
+ try {
+ ::decode(old_meta, iter);
+ } catch (const buffer::error &err) {
+ snapid_t snap_id = snap_id_from_key(it->first);
+ CLS_ERR("error decoding snapshot metadata for snap_id: %llu", snap_id.val);
+ return -EIO;
+ }
+ if (snap_meta.name == old_meta.name || snap_meta.id == old_meta.id) {
+ CLS_LOG(20, "snap_name %s or snap_id %llu matches existing snap %s %llu",
+ snap_meta.name.c_str(), snap_meta.id.val,
+ old_meta.name.c_str(), old_meta.id.val);
+ return -EEXIST;
+ }
+ }
+
+ if (vals.size() > 0)
+ last_read = vals.rbegin()->first;
+ } while (r == RBD_MAX_KEYS_READ);
+
+ // snapshot inherits parent, if any
+ cls_rbd_parent parent;
+ r = read_key(hctx, "parent", &parent);
+ if (r < 0 && r != -ENOENT)
+ return r;
+ if (r == 0) {
+ snap_meta.parent = parent;
+ }
+
+ bufferlist snap_metabl, snap_seqbl;
+ ::encode(snap_meta, snap_metabl);
+ ::encode(snap_meta.id, snap_seqbl);
+
+ string snapshot_key;
+ key_from_snap_id(snap_meta.id, &snapshot_key);
+ map<string, bufferlist> vals;
+ vals["snap_seq"] = snap_seqbl;
+ vals[snapshot_key] = snap_metabl;
+ r = cls_cxx_map_set_vals(hctx, &vals);
+ if (r < 0) {
+ CLS_ERR("error writing snapshot metadata: %d", r);
+ return r;
+ }
+
+ return 0;
+}
+
+/**
+ * Removes a snapshot from an rbd header.
+ *
+ * Input:
+ * @param snap_id the id of the snapshot to remove (uint64_t)
+ *
+ * Output:
+ * @returns 0 on success, negative error code on failure
+ */
+int snapshot_remove(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ snapid_t snap_id;
+
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(snap_id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "snapshot_remove id=%llu", snap_id.val);
+
+ // check if the key exists. we can't rely on remove_key doing this for
+ // us, since OMAPRMKEYS returns success if the key is not there.
+ // bug or feature? sounds like a bug, since tmap did not have this
+ // behavior, but cls_rgw may rely on it...
+ cls_rbd_snap snap;
+ string snapshot_key;
+ key_from_snap_id(snap_id, &snapshot_key);
+ int r = read_key(hctx, snapshot_key, &snap);
+ if (r == -ENOENT)
+ return -ENOENT;
+
+ if (snap.protection_status != RBD_PROTECTION_STATUS_UNPROTECTED)
+ return -EBUSY;
+
+ r = cls_cxx_map_remove_key(hctx, snapshot_key);
+ if (r < 0) {
+ CLS_ERR("error writing snapshot metadata: %d", r);
+ return r;
+ }
+
+ return 0;
+}
+
+/**
+ * Returns a uint64_t of all the features supported by this class.
+ */
+int get_all_features(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ uint64_t all_features = RBD_FEATURES_ALL;
+ ::encode(all_features, *out);
+ return 0;
+}
+
+/**
+ * "Copy up" data from the parent of a clone to the clone's object(s).
+ * Used for implementing copy-on-write for a clone image. Client
+ * will pass down a chunk of data that fits completely within one
+ * clone block (one object), and is aligned (starts at beginning of block),
+ * but may be shorter (for non-full parent blocks). The class method
+ * can't know the object size to validate the requested length,
+ * so it just writes the data as given if the child object doesn't
+ * already exist, and returns success if it does.
+ *
+ * Input:
+ * @param in bufferlist of data to write
+ *
+ * Output:
+ * @returns 0 on success, or if block already exists in child
+ * negative error code on other error
+ */
+
+int copyup(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ // check for existence; if child object exists, just return success
+ if (cls_cxx_stat(hctx, NULL, NULL) == 0)
+ return 0;
+ CLS_LOG(20, "copyup: writing length %d\n", in->length());
+ return cls_cxx_write(hctx, 0, in->length(), in);
+}
+
+
+/************************ rbd_id object methods **************************/
+
+/**
+ * Input:
+ * @param in ignored
+ *
+ * Output:
+ * @param id the id stored in the object
+ * @returns 0 on success, negative error code on failure
+ */
+int get_id(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ uint64_t size;
+ int r = cls_cxx_stat(hctx, &size, NULL);
+ if (r < 0)
+ return r;
+
+ if (size == 0)
+ return -ENOENT;
+
+ bufferlist read_bl;
+ r = cls_cxx_read(hctx, 0, size, &read_bl);
+ if (r < 0) {
+ CLS_ERR("get_id: could not read id: %d", r);
+ return r;
+ }
+
+ string id;
+ try {
+ bufferlist::iterator iter = read_bl.begin();
+ ::decode(id, iter);
+ } catch (const buffer::error &err) {
+ return -EIO;
+ }
+
+ ::encode(id, *out);
+ return 0;
+};
+
+/**
+ * Set the id of an image. The object must already exist.
+ *
+ * Input:
+ * @param id the id of the image, as an alpha-numeric string
+ *
+ * Output:
+ * @returns 0 on success, -EEXIST if the atomic create fails,
+ * negative error code on other error
+ */
+int set_id(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ int r = check_exists(hctx);
+ if (r < 0)
+ return r;
+
+ string id;
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ if (!is_valid_id(id)) {
+ CLS_ERR("set_id: invalid id '%s'", id.c_str());
+ return -EINVAL;
+ }
+
+ uint64_t size;
+ r = cls_cxx_stat(hctx, &size, NULL);
+ if (r < 0)
+ return r;
+ if (size != 0)
+ return -EEXIST;
+
+ CLS_LOG(20, "set_id: id=%s", id.c_str());
+
+ bufferlist write_bl;
+ ::encode(id, write_bl);
+ return cls_cxx_write(hctx, 0, write_bl.length(), &write_bl);
+}
+
+/*********************** methods for rbd_directory ***********************/
+
+static const string dir_key_for_id(const string &id)
+{
+ return RBD_DIR_ID_KEY_PREFIX + id;
+}
+
+static const string dir_key_for_name(const string &name)
+{
+ return RBD_DIR_NAME_KEY_PREFIX + name;
+}
+
+static const string dir_name_from_key(const string &key)
+{
+ return key.substr(strlen(RBD_DIR_NAME_KEY_PREFIX));
+}
+
+static int dir_add_image_helper(cls_method_context_t hctx,
+ const string &name, const string &id,
+ bool check_for_unique_id)
+{
+ if (!name.size() || !is_valid_id(id)) {
+ CLS_ERR("dir_add_image_helper: invalid name '%s' or id '%s'",
+ name.c_str(), id.c_str());
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "dir_add_image_helper name=%s id=%s", name.c_str(), id.c_str());
+
+ string tmp;
+ string name_key = dir_key_for_name(name);
+ string id_key = dir_key_for_id(id);
+ int r = read_key(hctx, name_key, &tmp);
+ if (r != -ENOENT) {
+ CLS_LOG(10, "name already exists");
+ return -EEXIST;
+ }
+ r = read_key(hctx, id_key, &tmp);
+ if (r != -ENOENT && check_for_unique_id) {
+ CLS_LOG(10, "id already exists");
+ return -EBADF;
+ }
+ bufferlist id_bl, name_bl;
+ ::encode(id, id_bl);
+ ::encode(name, name_bl);
+ map<string, bufferlist> omap_vals;
+ omap_vals[name_key] = id_bl;
+ omap_vals[id_key] = name_bl;
+ return cls_cxx_map_set_vals(hctx, &omap_vals);
+}
+
+static int dir_remove_image_helper(cls_method_context_t hctx,
+ const string &name, const string &id)
+{
+ CLS_LOG(20, "dir_remove_image_helper name=%s id=%s",
+ name.c_str(), id.c_str());
+
+ string stored_name, stored_id;
+ string name_key = dir_key_for_name(name);
+ string id_key = dir_key_for_id(id);
+ int r = read_key(hctx, name_key, &stored_id);
+ if (r < 0) {
+ CLS_ERR("error reading name to id mapping: %d", r);
+ return r;
+ }
+ r = read_key(hctx, id_key, &stored_name);
+ if (r < 0) {
+ CLS_ERR("error reading id to name mapping: %d", r);
+ return r;
+ }
+
+ // check if this op raced with a rename
+ if (stored_name != name || stored_id != id) {
+ CLS_ERR("stored name '%s' and id '%s' do not match args '%s' and '%s'",
+ stored_name.c_str(), stored_id.c_str(), name.c_str(), id.c_str());
+ return -ESTALE;
+ }
+
+ r = cls_cxx_map_remove_key(hctx, name_key);
+ if (r < 0) {
+ CLS_ERR("error removing name: %d", r);
+ return r;
+ }
+
+ r = cls_cxx_map_remove_key(hctx, id_key);
+ if (r < 0) {
+ CLS_ERR("error removing id: %d", r);
+ return r;
+ }
+
+ return 0;
+}
+
+/**
+ * Rename an image in the directory, updating both indexes
+ * atomically. This can't be done from the client calling
+ * dir_add_image and dir_remove_image in one transaction because the
+ * results of the first method are not visibale to later steps.
+ *
+ * Input:
+ * @param src original name of the image
+ * @param dest new name of the image
+ * @param id the id of the image
+ *
+ * Output:
+ * @returns -ESTALE if src and id do not map to each other
+ * @returns -ENOENT if src or id are not in the directory
+ * @returns -EEXIST if dest already exists
+ * @returns 0 on success, negative error code on failure
+ */
+int dir_rename_image(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ string src, dest, id;
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(src, iter);
+ ::decode(dest, iter);
+ ::decode(id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ int r = dir_remove_image_helper(hctx, src, id);
+ if (r < 0)
+ return r;
+ // ignore duplicate id because the result of
+ // remove_image_helper is not visible yet
+ return dir_add_image_helper(hctx, dest, id, false);
+}
+
+/**
+ * Get the id of an image given its name.
+ *
+ * Input:
+ * @param name the name of the image
+ *
+ * Output:
+ * @param id the id of the image
+ * @returns 0 on success, negative error code on failure
+ */
+int dir_get_id(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ string name;
+
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(name, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "dir_get_id: name=%s", name.c_str());
+
+ string id;
+ int r = read_key(hctx, dir_key_for_name(name), &id);
+ if (r < 0) {
+ CLS_ERR("error reading id for name '%s': %d", name.c_str(), r);
+ return r;
+ }
+ ::encode(id, *out);
+ return 0;
+}
+
+/**
+ * Get the name of an image given its id.
+ *
+ * Input:
+ * @param id the id of the image
+ *
+ * Output:
+ * @param name the name of the image
+ * @returns 0 on success, negative error code on failure
+ */
+int dir_get_name(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ string id;
+
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ CLS_LOG(20, "dir_get_name: id=%s", id.c_str());
+
+ string name;
+ int r = read_key(hctx, dir_key_for_id(id), &name);
+ if (r < 0) {
+ CLS_ERR("error reading name for id '%s': %d", id.c_str(), r);
+ return r;
+ }
+ ::encode(name, *out);
+ return 0;
+}
+
+/**
+ * List the names and ids of the images in the directory, sorted by
+ * name.
+ *
+ * Input:
+ * @param start_after which name to begin listing after
+ * (use the empty string to start at the beginning)
+ * @param max_return the maximum number of names to list
+ *
+ * Output:
+ * @param images map from name to id of up to max_return images
+ * @returns 0 on success, negative error code on failure
+ */
+int dir_list(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ string start_after;
+ uint64_t max_return;
+
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(start_after, iter);
+ ::decode(max_return, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ int max_read = RBD_MAX_KEYS_READ;
+ int r = max_read;
+ map<string, string> images;
+ string last_read = dir_key_for_name(start_after);
+
+ while (r == max_read && images.size() < max_return) {
+ map<string, bufferlist> vals;
+ CLS_LOG(20, "last_read = '%s'", last_read.c_str());
+ r = cls_cxx_map_get_vals(hctx, last_read, RBD_DIR_NAME_KEY_PREFIX,
+ max_read, &vals);
+ if (r < 0) {
+ CLS_ERR("error reading directory by name: %d", r);
+ return r;
+ }
+
+ for (map<string, bufferlist>::iterator it = vals.begin();
+ it != vals.end(); ++it) {
+ string id;
+ bufferlist::iterator iter = it->second.begin();
+ try {
+ ::decode(id, iter);
+ } catch (const buffer::error &err) {
+ CLS_ERR("could not decode id of image '%s'", it->first.c_str());
+ return -EIO;
+ }
+ CLS_LOG(20, "adding '%s' -> '%s'", dir_name_from_key(it->first).c_str(), id.c_str());
+ images[dir_name_from_key(it->first)] = id;
+ if (images.size() >= max_return)
+ break;
+ }
+ if (vals.size() > 0) {
++ last_read = dir_key_for_name(images.rbegin()->first);
+ }
+ }
+
+ ::encode(images, *out);
+
+ return 0;
+}
+
+/**
+ * Add an image to the rbd directory. Creates the directory object if
+ * needed, and updates the index from id to name and name to id.
+ *
+ * Input:
+ * @param name the name of the image
+ * @param id the id of the image
+ *
+ * Output:
+ * @returns -EEXIST if the image name is already in the directory
+ * @returns -EBADF if the image id is already in the directory
+ * @returns 0 on success, negative error code on failure
+ */
+int dir_add_image(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ int r = cls_cxx_create(hctx, false);
+ if (r < 0) {
+ CLS_ERR("could not create directory: error %d", r);
+ return r;
+ }
+
+ string name, id;
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(name, iter);
+ ::decode(id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ return dir_add_image_helper(hctx, name, id, true);
+}
+
+/**
+ * Remove an image from the rbd directory.
+ *
+ * Input:
+ * @param name the name of the image
+ * @param id the id of the image
+ *
+ * Output:
+ * @returns -ESTALE if the name and id do not map to each other
+ * @returns 0 on success, negative error code on failure
+ */
+int dir_remove_image(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ string name, id;
+ try {
+ bufferlist::iterator iter = in->begin();
+ ::decode(name, iter);
+ ::decode(id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+
+ return dir_remove_image_helper(hctx, name, id);
+}
+
+/****************************** Old format *******************************/
+
+int old_snapshots_list(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ bufferlist bl;
+ struct rbd_obj_header_ondisk *header;
+ int rc = snap_read_header(hctx, bl);
+ if (rc < 0)
+ return rc;
+
+ header = (struct rbd_obj_header_ondisk *)bl.c_str();
+ bufferptr p(header->snap_names_len);
+ char *buf = (char *)header;
+ char *name = buf + sizeof(*header) + header->snap_count * sizeof(struct rbd_obj_snap_ondisk);
+ char *end = name + header->snap_names_len;
+ memcpy(p.c_str(),
+ buf + sizeof(*header) + header->snap_count * sizeof(struct rbd_obj_snap_ondisk),
+ header->snap_names_len);
+
+ ::encode(header->snap_seq, *out);
+ ::encode(header->snap_count, *out);
+
+ for (unsigned i = 0; i < header->snap_count; i++) {
+ string s = name;
+ ::encode(header->snaps[i].id, *out);
+ ::encode(header->snaps[i].image_size, *out);
+ ::encode(s, *out);
+
+ name += strlen(name) + 1;
+ if (name > end)
+ return -EIO;
+ }
+
+ return 0;
+}
+
+int old_snapshot_add(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ bufferlist bl;
+ struct rbd_obj_header_ondisk *header;
+ bufferlist newbl;
+ bufferptr header_bp(sizeof(*header));
+ struct rbd_obj_snap_ondisk *new_snaps;
+
+ int rc = snap_read_header(hctx, bl);
+ if (rc < 0)
+ return rc;
+
+ header = (struct rbd_obj_header_ondisk *)bl.c_str();
+
+ int snaps_id_ofs = sizeof(*header);
+ int len = snaps_id_ofs;
+ int names_ofs = snaps_id_ofs + sizeof(*new_snaps) * header->snap_count;
+ const char *snap_name;
+ const char *snap_names = ((char *)header) + names_ofs;
+ const char *end = snap_names + header->snap_names_len;
+ bufferlist::iterator iter = in->begin();
+ string s;
+ uint64_t snap_id;
+
+ try {
+ ::decode(s, iter);
+ ::decode(snap_id, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+ snap_name = s.c_str();
+
+ if (header->snap_seq > snap_id)
+ return -ESTALE;
+
+ const char *cur_snap_name;
+ for (cur_snap_name = snap_names; cur_snap_name < end; cur_snap_name += strlen(cur_snap_name) + 1) {
+ if (strncmp(cur_snap_name, snap_name, end - cur_snap_name) == 0)
+ return -EEXIST;
+ }
+ if (cur_snap_name > end)
+ return -EIO;
+
+ int snap_name_len = strlen(snap_name);
+
+ bufferptr new_names_bp(header->snap_names_len + snap_name_len + 1);
+ bufferptr new_snaps_bp(sizeof(*new_snaps) * (header->snap_count + 1));
+
+ /* copy snap names and append to new snap name */
+ char *new_snap_names = new_names_bp.c_str();
+ strcpy(new_snap_names, snap_name);
+ memcpy(new_snap_names + snap_name_len + 1, snap_names, header->snap_names_len);
+
+ /* append new snap id */
+ new_snaps = (struct rbd_obj_snap_ondisk *)new_snaps_bp.c_str();
+ memcpy(new_snaps + 1, header->snaps, sizeof(*new_snaps) * header->snap_count);
+
+ header->snap_count = header->snap_count + 1;
+ header->snap_names_len = header->snap_names_len + snap_name_len + 1;
+ header->snap_seq = snap_id;
+
+ new_snaps[0].id = snap_id;
+ new_snaps[0].image_size = header->image_size;
+
+ len += sizeof(*new_snaps) * header->snap_count + header->snap_names_len;
+
+ memcpy(header_bp.c_str(), header, sizeof(*header));
+
+ newbl.push_back(header_bp);
+ newbl.push_back(new_snaps_bp);
+ newbl.push_back(new_names_bp);
+
+ rc = cls_cxx_write_full(hctx, &newbl);
+ if (rc < 0)
+ return rc;
+
+ return 0;
+}
+
+int old_snapshot_remove(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ bufferlist bl;
+ struct rbd_obj_header_ondisk *header;
+ bufferlist newbl;
+ bufferptr header_bp(sizeof(*header));
+ struct rbd_obj_snap_ondisk *new_snaps;
+
+ int rc = snap_read_header(hctx, bl);
+ if (rc < 0)
+ return rc;
+
+ header = (struct rbd_obj_header_ondisk *)bl.c_str();
+
+ int snaps_id_ofs = sizeof(*header);
+ int names_ofs = snaps_id_ofs + sizeof(*new_snaps) * header->snap_count;
+ const char *snap_name;
+ const char *snap_names = ((char *)header) + names_ofs;
+ const char *orig_names = snap_names;
+ const char *end = snap_names + header->snap_names_len;
+ bufferlist::iterator iter = in->begin();
+ string s;
+ unsigned i;
+ bool found = false;
+ struct rbd_obj_snap_ondisk snap;
+
+ try {
+ ::decode(s, iter);
+ } catch (const buffer::error &err) {
+ return -EINVAL;
+ }
+ snap_name = s.c_str();
+
+ for (i = 0; snap_names < end; i++) {
+ if (strcmp(snap_names, snap_name) == 0) {
+ snap = header->snaps[i];
+ found = true;
+ break;
+ }
+ snap_names += strlen(snap_names) + 1;
+ }
+ if (!found) {
+ CLS_ERR("couldn't find snap %s\n", snap_name);
+ return -ENOENT;
+ }
+
+ header->snap_names_len = header->snap_names_len - (s.length() + 1);
+ header->snap_count = header->snap_count - 1;
+
+ bufferptr new_names_bp(header->snap_names_len);
+ bufferptr new_snaps_bp(sizeof(header->snaps[0]) * header->snap_count);
+
+ memcpy(header_bp.c_str(), header, sizeof(*header));
+ newbl.push_back(header_bp);
+
+ if (header->snap_count) {
+ int snaps_len = 0;
+ int names_len = 0;
+ CLS_LOG(20, "i=%d\n", i);
+ if (i > 0) {
+ snaps_len = sizeof(header->snaps[0]) * i;
+ names_len = snap_names - orig_names;
+ memcpy(new_snaps_bp.c_str(), header->snaps, snaps_len);
+ memcpy(new_names_bp.c_str(), orig_names, names_len);
+ }
+ snap_names += s.length() + 1;
+
+ if (i < header->snap_count) {
+ memcpy(new_snaps_bp.c_str() + snaps_len,
+ header->snaps + i + 1,
+ sizeof(header->snaps[0]) * (header->snap_count - i));
+ memcpy(new_names_bp.c_str() + names_len, snap_names , end - snap_names);
+ }
+ newbl.push_back(new_snaps_bp);
+ newbl.push_back(new_names_bp);
+ }
+
+ rc = cls_cxx_write_full(hctx, &newbl);
+ if (rc < 0)
+ return rc;
+
+ return 0;
+
+}
+
+
+/* assign block id. This method should be called on the rbd_info object */
+int rbd_assign_bid(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ struct rbd_info info;
+ int rc;
+ bufferlist bl;
+
+ rc = cls_cxx_read(hctx, 0, sizeof(info), &bl);
+ if (rc < 0 && rc != -EEXIST)
+ return rc;
+
+ if (rc && rc < (int)sizeof(info)) {
+ CLS_ERR("bad rbd_info object, read %d bytes, expected %d", rc, sizeof(info));
+ return -EIO;
+ }
+
+ uint64_t max_id;
+ if (rc) {
+ memcpy(&info, bl.c_str(), sizeof(info));
+ max_id = info.max_id + 1;
+ info.max_id = max_id;
+ } else {
+ memset(&info, 0, sizeof(info));
+ max_id = 0;
+ }
+
+ bufferlist newbl;
+ bufferptr bp(sizeof(info));
+ memcpy(bp.c_str(), &info, sizeof(info));
+ newbl.push_back(bp);
+ rc = cls_cxx_write_full(hctx, &newbl);
+ if (rc < 0) {
+ CLS_ERR("error writing rbd_info, got rc=%d", rc);
+ return rc;
+ }
+
+ ::encode(max_id, *out);
+
+ return out->length();
+}
+
+void __cls_init()
+{
+ CLS_LOG(20, "Loaded rbd class!");
+
+ cls_register("rbd", &h_class);
+ cls_register_cxx_method(h_class, "create",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ create, &h_create);
+ cls_register_cxx_method(h_class, "get_features",
+ CLS_METHOD_RD,
+ get_features, &h_get_features);
+ cls_register_cxx_method(h_class, "get_size",
+ CLS_METHOD_RD,
+ get_size, &h_get_size);
+ cls_register_cxx_method(h_class, "set_size",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ set_size, &h_set_size);
+ cls_register_cxx_method(h_class, "get_snapcontext",
+ CLS_METHOD_RD,
+ get_snapcontext, &h_get_snapcontext);
+ cls_register_cxx_method(h_class, "get_object_prefix",
+ CLS_METHOD_RD,
+ get_object_prefix, &h_get_object_prefix);
+ cls_register_cxx_method(h_class, "get_snapshot_name",
+ CLS_METHOD_RD,
+ get_snapshot_name, &h_get_snapshot_name);
+ cls_register_cxx_method(h_class, "snapshot_add",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ snapshot_add, &h_snapshot_add);
+ cls_register_cxx_method(h_class, "snapshot_remove",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ snapshot_remove, &h_snapshot_remove);
+ cls_register_cxx_method(h_class, "get_all_features",
+ CLS_METHOD_RD,
+ get_all_features, &h_get_all_features);
+ cls_register_cxx_method(h_class, "copyup",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ copyup, &h_copyup);
+ cls_register_cxx_method(h_class, "get_parent",
+ CLS_METHOD_RD,
+ get_parent, &h_get_parent);
+ cls_register_cxx_method(h_class, "set_parent",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ set_parent, &h_set_parent);
+ cls_register_cxx_method(h_class, "remove_parent",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ remove_parent, &h_remove_parent);
+ cls_register_cxx_method(h_class, "set_protection_status",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ set_protection_status, &h_set_protection_status);
+ cls_register_cxx_method(h_class, "get_protection_status",
+ CLS_METHOD_RD,
+ get_protection_status, &h_get_protection_status);
+ cls_register_cxx_method(h_class, "get_stripe_unit_count",
+ CLS_METHOD_RD,
+ get_stripe_unit_count, &h_get_stripe_unit_count);
+ cls_register_cxx_method(h_class, "set_stripe_unit_count",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ set_stripe_unit_count, &h_set_stripe_unit_count);
+
+ /* methods for the rbd_children object */
+ cls_register_cxx_method(h_class, "add_child",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ add_child, &h_add_child);
+ cls_register_cxx_method(h_class, "remove_child",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ remove_child, &h_remove_child);
+ cls_register_cxx_method(h_class, "get_children",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ get_children, &h_get_children);
+
+ /* methods for the rbd_id.$image_name objects */
+ cls_register_cxx_method(h_class, "get_id",
+ CLS_METHOD_RD,
+ get_id, &h_get_id);
+ cls_register_cxx_method(h_class, "set_id",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ set_id, &h_set_id);
+
+ /* methods for the rbd_directory object */
+ cls_register_cxx_method(h_class, "dir_get_id",
+ CLS_METHOD_RD,
+ dir_get_id, &h_dir_get_id);
+ cls_register_cxx_method(h_class, "dir_get_name",
+ CLS_METHOD_RD,
+ dir_get_name, &h_dir_get_name);
+ cls_register_cxx_method(h_class, "dir_list",
+ CLS_METHOD_RD,
+ dir_list, &h_dir_list);
+ cls_register_cxx_method(h_class, "dir_add_image",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ dir_add_image, &h_dir_add_image);
+ cls_register_cxx_method(h_class, "dir_remove_image",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ dir_remove_image, &h_dir_remove_image);
+ cls_register_cxx_method(h_class, "dir_rename_image",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ dir_rename_image, &h_dir_rename_image);
+
+ /* methods for the old format */
+ cls_register_cxx_method(h_class, "snap_list",
+ CLS_METHOD_RD,
+ old_snapshots_list, &h_old_snapshots_list);
+ cls_register_cxx_method(h_class, "snap_add",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ old_snapshot_add, &h_old_snapshot_add);
+ cls_register_cxx_method(h_class, "snap_remove",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ old_snapshot_remove, &h_old_snapshot_remove);
+
+ /* assign a unique block id for rbd blocks */
+ cls_register_cxx_method(h_class, "assign_bid",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ rbd_assign_bid, &h_assign_bid);
+
+ return;
+}
projects / ceph.git / commitdiff