ceph/src/tools/cephfs/PgFiles.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2016 Red Hat
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15 #include "common/errno.h"
  16 #include "osdc/Striper.h"
  17
  18 #include "PgFiles.h"
  19
  20
  21 #define dout_context g_ceph_context
  22 #define dout_subsys ceph_subsys_mds
  23 #undef dout_prefix
  24 #define dout_prefix *_dout << "pgeffects." << __func__ << ": "
  25
  26 int PgFiles::init()
  27 {
  28   int r = ceph_create_with_context(&cmount, g_ceph_context);
  29   if (r != 0) {
  30     return r;
  31   }
  32
  33   return ceph_init(cmount);
  34 }
  35
  36 PgFiles::PgFiles(Objecter *o, const std::set<pg_t> &pgs_)
  37   : objecter(o), pgs(pgs_)
  38 {
  39   for (const auto &i : pgs) {
  40     pools.insert(i.m_pool);
  41   }
  42 }
  43
  44 PgFiles::~PgFiles()
  45 {
  46   ceph_release(cmount);
  47 }
  48
  49 void PgFiles::hit_dir(std::string const &path)
  50 {
  51   dout(10) << "entering " << path << dendl;
  52
  53   ceph_dir_result *dr = nullptr;
  54   int r = ceph_opendir(cmount, path.c_str(), &dr);
  55   if (r != 0) {
  56     derr << "Failed to open path: " << cpp_strerror(r) << dendl;
  57     return;
  58   }
  59
  60   struct dirent de;
  61   while((r = ceph_readdir_r(cmount, dr, &de)) != 0) {
  62     if (r < 0) {
  63       derr << "Error reading path " << path << ": " << cpp_strerror(r)
  64            << dendl;
  65       ceph_closedir(cmount, dr); // best effort, ignore r
  66       return;
  67     }
  68
  69     if (std::string(de.d_name) == "." || std::string(de.d_name) == "..") {
  70       continue;
  71     }
  72
  73     struct ceph_statx stx;
  74     std::string de_path = (path + std::string("/") + de.d_name);
  75     r = ceph_statx(cmount, de_path.c_str(), &stx,
  76                     CEPH_STATX_INO|CEPH_STATX_SIZE, 0);
  77     if (r != 0) {
  78       derr << "Failed to stat path " << de_path << ": "
  79             << cpp_strerror(r) << dendl;
  80       // Don't hold up the whole process for one bad inode
  81       continue;
  82     }
  83
  84     if (S_ISREG(stx.stx_mode)) {
  85       hit_file(de_path, stx);
  86     } else if (S_ISDIR(stx.stx_mode)) {
  87       hit_dir(de_path);
  88     } else {
  89       dout(20) << "Skipping non reg/dir file: " << de_path << dendl;
  90     }
  91   }
  92
  93   r = ceph_closedir(cmount, dr);
  94   if (r != 0) {
  95     derr << "Error closing path " << path << ": " << cpp_strerror(r) << dendl;
  96     return;
  97   }
  98 }
  99
 100 void PgFiles::hit_file(std::string const &path, const struct ceph_statx &stx)
 101 {
 102   ceph_assert(S_ISREG(stx.stx_mode));
 103
 104   dout(20) << "Hitting file '" << path << "'" << dendl;
 105
 106   int l_stripe_unit = 0;
 107   int l_stripe_count = 0;
 108   int l_object_size = 0;
 109   int l_pool_id = 0;
 110   int r = ceph_get_path_layout(cmount, path.c_str(), &l_stripe_unit,
 111                                &l_stripe_count, &l_object_size,
 112                                &l_pool_id);
 113   if (r != 0) {
 114     derr << "Error reading layout on " << path << ": " << cpp_strerror(r)
 115          << dendl;
 116     return;
 117   }
 118
 119   struct file_layout_t layout;
 120   layout.stripe_unit = l_stripe_unit;
 121   layout.stripe_count = l_stripe_count;
 122   layout.object_size = l_object_size;
 123   layout.pool_id = l_pool_id;
 124
 125   // Avoid calculating PG if the layout targeted a completely different pool
 126   if (pools.count(layout.pool_id) == 0) {
 127     dout(20) << "Fast check missed: pool " << layout.pool_id << " not in "
 128                 "target set" << dendl;
 129     return;
 130   }
 131
 132   auto num_objects = Striper::get_num_objects(layout, stx.stx_size);
 133
 134   for (uint64_t i = 0; i < num_objects; ++i) {
 135     char buf[32];
 136     snprintf(buf, sizeof(buf), "%llx.%08llx", (long long unsigned)stx.stx_ino,
 137                                               (long long unsigned int)i);
 138     dout(20) << "  object " << std::string(buf) << dendl;
 139
 140     pg_t target;
 141     object_t oid;
 142     object_locator_t loc;
 143     loc.pool = layout.pool_id;
 144     loc.key = std::string(buf);
 145
 146     unsigned pg_num_mask = 0;
 147     unsigned pg_num = 0;
 148
 149     int r = 0;
 150     objecter->with_osdmap([&r, oid, loc, &target, &pg_num_mask, &pg_num]
 151                           (const OSDMap &osd_map) {
 152       r = osd_map.object_locator_to_pg(oid, loc, target);
 153       if (r == 0) {
 154         auto pool = osd_map.get_pg_pool(loc.pool);
 155         pg_num_mask = pool->get_pg_num_mask();
 156         pg_num = pool->get_pg_num();
 157       }
 158     });
 159     if (r != 0) {
 160       // Can happen if layout pointed to pool not in osdmap, for example
 161       continue;
 162     }
 163
 164     target.m_seed = ceph_stable_mod(target.ps(), pg_num, pg_num_mask);
 165
 166     dout(20) << "  target " << target << dendl;
 167
 168     if (pgs.count(target)) {
 169       std::cout << path << std::endl;
 170       return;
 171     }
 172   }
 173
 174 }
 175
 176 int PgFiles::scan_path(std::string const &path)
 177 {
 178   int r = ceph_mount(cmount, "/");
 179   if (r != 0) {
 180     derr << "Failed to mount: " << cpp_strerror(r) << dendl;
 181     return r;
 182   }
 183
 184   hit_dir(path);
 185
 186   r = ceph_unmount(cmount);
 187   if (r != 0) {
 188     derr << "Failed to unmount: " << cpp_strerror(r) << dendl;
 189     return r;
 190   }
 191
 192   return r;
 193 }
 194