ceph/src/librbd/operation/RenameRequest.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #include "librbd/operation/RenameRequest.h"
   5 #include "common/dout.h"
   6 #include "common/errno.h"
   7 #include "include/rados/librados.hpp"
   8 #include "librbd/ImageCtx.h"
   9 #include "librbd/internal.h"
  10 #include "librbd/Utils.h"
  11
  12 #define dout_subsys ceph_subsys_rbd
  13 #undef dout_prefix
  14 #define dout_prefix *_dout << "librbd::operation::RenameRequest: "
  15
  16 namespace librbd {
  17 namespace operation {
  18
  19 namespace {
  20
  21 template <typename I>
  22 std::ostream& operator<<(std::ostream& os,
  23                          const typename RenameRequest<I>::State& state) {
  24   switch(state) {
  25   case RenameRequest<I>::STATE_READ_SOURCE_HEADER:
  26     os << "READ_SOURCE_HEADER";
  27     break;
  28   case RenameRequest<I>::STATE_WRITE_DEST_HEADER:
  29     os << "WRITE_DEST_HEADER";
  30     break;
  31   case RenameRequest<I>::STATE_UPDATE_DIRECTORY:
  32     os << "UPDATE_DIRECTORY";
  33     break;
  34   case RenameRequest<I>::STATE_REMOVE_SOURCE_HEADER:
  35     os << "REMOVE_SOURCE_HEADER";
  36     break;
  37   default:
  38     os << "UNKNOWN (" << static_cast<uint32_t>(state) << ")";
  39     break;
  40   }
  41   return os;
  42 }
  43
  44 } // anonymous namespace
  45
  46 template <typename I>
  47 RenameRequest<I>::RenameRequest(I &image_ctx, Context *on_finish,
  48                                 const std::string &dest_name)
  49   : Request<I>(image_ctx, on_finish), m_dest_name(dest_name),
  50     m_source_oid(image_ctx.old_format ? util::old_header_name(image_ctx.name) :
  51                                         util::id_obj_name(image_ctx.name)),
  52     m_dest_oid(image_ctx.old_format ? util::old_header_name(dest_name) :
  53                                       util::id_obj_name(dest_name)) {
  54 }
  55
  56 template <typename I>
  57 void RenameRequest<I>::send_op() {
  58   send_read_source_header();
  59 }
  60
  61 template <typename I>
  62 bool RenameRequest<I>::should_complete(int r) {
  63   I &image_ctx = this->m_image_ctx;
  64   CephContext *cct = image_ctx.cct;
  65   ldout(cct, 5) << this << " " << __func__ << ": state=" << m_state << ", "
  66                 << "r=" << r << dendl;
  67   r = filter_return_code(r);
  68   if (r < 0) {
  69     if (r == -EEXIST) {
  70       ldout(cct, 1) << "image already exists" << dendl;
  71     } else {
  72       lderr(cct) << "encountered error: " << cpp_strerror(r) << dendl;
  73     }
  74     return true;
  75   }
  76
  77   if (m_state == STATE_UPDATE_DIRECTORY) {
  78     // update in-memory name before removing source header
  79     apply();
  80   } else if (m_state == STATE_REMOVE_SOURCE_HEADER) {
  81     return true;
  82   }
  83
  84   std::shared_lock owner_lock{image_ctx.owner_lock};
  85   switch (m_state) {
  86   case STATE_READ_SOURCE_HEADER:
  87     send_write_destination_header();
  88     break;
  89   case STATE_WRITE_DEST_HEADER:
  90     send_update_directory();
  91     break;
  92   case STATE_UPDATE_DIRECTORY:
  93     send_remove_source_header();
  94     break;
  95   default:
  96     ceph_abort();
  97     break;
  98   }
  99   return false;
 100 }
 101
 102 template <typename I>
 103 int RenameRequest<I>::filter_return_code(int r) const {
 104   I &image_ctx = this->m_image_ctx;
 105   CephContext *cct = image_ctx.cct;
 106
 107   if (m_state == STATE_READ_SOURCE_HEADER && r == -ENOENT) {
 108     std::shared_lock image_locker{image_ctx.image_lock};
 109     if (image_ctx.name == m_dest_name) {
 110       // signal that replay raced with itself
 111       return -EEXIST;
 112     }
 113   } else if (m_state == STATE_REMOVE_SOURCE_HEADER && r < 0) {
 114     if (r != -ENOENT) {
 115       lderr(cct) << "warning: couldn't remove old source object ("
 116                  << m_source_oid << ")" << dendl;
 117     }
 118     return 0;
 119   }
 120   return r;
 121 }
 122
 123 template <typename I>
 124 void RenameRequest<I>::send_read_source_header() {
 125   I &image_ctx = this->m_image_ctx;
 126   CephContext *cct = image_ctx.cct;
 127   ldout(cct, 5) << this << " " << __func__ << dendl;
 128   m_state = STATE_READ_SOURCE_HEADER;
 129
 130   librados::ObjectReadOperation op;
 131   op.read(0, 0, NULL, NULL);
 132
 133   // TODO: old code read omap values but there are no omap values on the
 134   //       old format header nor the new format id object
 135   librados::AioCompletion *rados_completion = this->create_callback_completion();
 136   int r = image_ctx.md_ctx.aio_operate(m_source_oid, rados_completion, &op,
 137                                        &m_header_bl);
 138   ceph_assert(r == 0);
 139   rados_completion->release();
 140 }
 141
 142 template <typename I>
 143 void RenameRequest<I>::send_write_destination_header() {
 144   I &image_ctx = this->m_image_ctx;
 145   CephContext *cct = image_ctx.cct;
 146   ldout(cct, 5) << this << " " << __func__ << dendl;
 147   m_state = STATE_WRITE_DEST_HEADER;
 148
 149   librados::ObjectWriteOperation op;
 150   op.create(true);
 151   op.write_full(m_header_bl);
 152
 153   librados::AioCompletion *rados_completion = this->create_callback_completion();
 154   int r = image_ctx.md_ctx.aio_operate(m_dest_oid, rados_completion, &op);
 155   ceph_assert(r == 0);
 156   rados_completion->release();
 157 }
 158
 159 template <typename I>
 160 void RenameRequest<I>::send_update_directory() {
 161   I &image_ctx = this->m_image_ctx;
 162   CephContext *cct = image_ctx.cct;
 163   ldout(cct, 5) << this << " " << __func__ << dendl;
 164   m_state = STATE_UPDATE_DIRECTORY;
 165
 166   librados::ObjectWriteOperation op;
 167   if (image_ctx.old_format) {
 168     bufferlist cmd_bl;
 169     bufferlist empty_bl;
 170     encode(static_cast<__u8>(CEPH_OSD_TMAP_SET), cmd_bl);
 171     encode(m_dest_name, cmd_bl);
 172     encode(empty_bl, cmd_bl);
 173     encode(static_cast<__u8>(CEPH_OSD_TMAP_RM), cmd_bl);
 174     encode(image_ctx.name, cmd_bl);
 175     op.tmap_update(cmd_bl);
 176   } else {
 177     cls_client::dir_rename_image(&op, image_ctx.name, m_dest_name,
 178                                  image_ctx.id);
 179   }
 180
 181   librados::AioCompletion *rados_completion = this->create_callback_completion();
 182   int r = image_ctx.md_ctx.aio_operate(RBD_DIRECTORY, rados_completion, &op);
 183   ceph_assert(r == 0);
 184   rados_completion->release();
 185 }
 186
 187 template <typename I>
 188 void RenameRequest<I>::send_remove_source_header() {
 189   I &image_ctx = this->m_image_ctx;
 190   CephContext *cct = image_ctx.cct;
 191   ldout(cct, 5) << this << " " << __func__ << dendl;
 192   m_state = STATE_REMOVE_SOURCE_HEADER;
 193
 194   librados::ObjectWriteOperation op;
 195   op.remove();
 196
 197   librados::AioCompletion *rados_completion = this->create_callback_completion();
 198   int r = image_ctx.md_ctx.aio_operate(m_source_oid, rados_completion, &op);
 199   ceph_assert(r == 0);
 200   rados_completion->release();
 201 }
 202
 203 template <typename I>
 204 void RenameRequest<I>::apply() {
 205   I &image_ctx = this->m_image_ctx;
 206   image_ctx.set_image_name(m_dest_name);
 207 }
 208
 209 } // namespace operation
 210 } // namespace librbd
 211
 212 template class librbd::operation::RenameRequest<librbd::ImageCtx>;