ceph/src/osdc/Striper.h
Sage Weil d68a80622c striper: expose method that works directrly from a map<>
Some callers will want to call the stripe method multiple times and
accumulate IO on a single result set.  Expose access to the map<> that was
previously internally used for this and do the map -> vector conversion
in a wrapper.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-10-15 15:34:07 -07:00

95 lines
2.8 KiB
C++

// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
// vim: ts=8 sw=2 smarttab
/*
* Ceph - scalable distributed file system
*
* Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
*
* This is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License version 2.1, as published by the Free Software
* Foundation. See file COPYING.
*
*/
#ifndef CEPH_STRIPER_H
#define CEPH_STRIPER_H
#include "include/types.h"
#include "osd/osd_types.h"
class CephContext;
//namespace ceph {
class Striper {
public:
/*
* map (ino, layout, offset, len) to a (list of) OSDExtents (byte
* ranges in objects on (primary) osds)
*/
static void file_to_extents(CephContext *cct, const char *object_format,
ceph_file_layout *layout,
uint64_t offset, uint64_t len,
map<object_t, vector<ObjectExtent> >& extents,
uint64_t buffer_offset=0);
static void file_to_extents(CephContext *cct, const char *object_format,
ceph_file_layout *layout,
uint64_t offset, uint64_t len,
vector<ObjectExtent>& extents,
uint64_t buffer_offset=0);
static void file_to_extents(CephContext *cct, inodeno_t ino,
ceph_file_layout *layout,
uint64_t offset, uint64_t len,
vector<ObjectExtent>& extents) {
// generate prefix/format
char buf[32];
snprintf(buf, sizeof(buf), "%llx.%%08llx", (long long unsigned)ino);
file_to_extents(cct, buf, layout, offset, len, extents);
}
static void assimilate_extents(map<object_t,vector<ObjectExtent> >& object_extents,
vector<ObjectExtent>& extents);
/**
* reverse map an object extent to file extents
*/
static void extent_to_file(CephContext *cct, ceph_file_layout *layout,
uint64_t objectno, uint64_t off, uint64_t len,
vector<pair<uint64_t, uint64_t> >& extents);
/*
* helper to assemble a striped result
*/
class StripedReadResult {
map<uint64_t, pair<bufferlist, uint64_t> > partial; // offset -> (data, intended length)
public:
void add_partial_result(CephContext *cct,
bufferlist& bl,
const vector<pair<uint64_t,uint64_t> >& buffer_extents);
/**
* add sparse read into results
*
* @param bl buffer
* @param bl_map map of which logical source extents this covers
* @param bl_off logical buffer offset (e.g., first bl_map key if the buffer is not sparse)
* @param buffer_extents output buffer extents the data maps to
*/
void add_partial_sparse_result(CephContext *cct,
bufferlist& bl, const map<uint64_t, uint64_t>& bl_map,
uint64_t bl_off,
const vector<pair<uint64_t,uint64_t> >& buffer_extents);
void assemble_result(CephContext *cct, bufferlist& bl, bool zero_tail);
};
};
//};
#endif