Commit 56cf7a53 authored by knielsen@ymer.(none)'s avatar knielsen@ymer.(none)
Browse files

BUG#27370: Potential inconsistent blob reads for ReadCommitted reads. 

The old blob implementation had code that attempted to upgrade the lock mode for
LM_CommittedRead operations, but it did not work properly as it did not recompute
the operation flags.

As a consequence, reading a blob with LM_CommittedRead could return inconsistent
data, with different part of the read data being from different commits done by
other transactions.

The fix is to correctly recompute all necessary flags when upgrading lock mode.
parent 01189d96

mysql-test/r/bdb_notembedded.result

0 → 100644
+35 −0
Original line number Diff line number Diff line 
set autocommit=1;

reset master;

create table bug16206 (a int);

insert into bug16206 values(1);

start transaction;

insert into bug16206 values(2);

commit;

show binlog events;

Log_name	Pos	Event_type	Server_id	End_log_pos	Info

f	n	Format_desc	1	n	Server ver: VERSION, Binlog ver: 4

f	n	Query	1	n	use `test`; create table bug16206 (a int)

f	n	Query	1	n	use `test`; insert into bug16206 values(1)

f	n	Query	1	n	use `test`; insert into bug16206 values(2)

drop table bug16206;

reset master;

create table bug16206 (a int) engine=         bdb;

insert into bug16206 values(0);

insert into bug16206 values(1);

start transaction;

insert into bug16206 values(2);

commit;

insert into bug16206 values(3);

show binlog events;

Log_name	Pos	Event_type	Server_id	End_log_pos	Info

f	n	Format_desc	1	n	Server ver: VERSION, Binlog ver: 4

f	n	Query	1	n	use `test`; create table bug16206 (a int) engine=         bdb

f	n	Query	1	n	use `test`; insert into bug16206 values(0)

f	n	Query	1	n	use `test`; insert into bug16206 values(1)

f	n	Query	1	n	use `test`; BEGIN

f	n	Query	1	n	use `test`; insert into bug16206 values(2)

f	n	Query	1	n	use `test`; COMMIT

f	n	Query	1	n	use `test`; insert into bug16206 values(3)

drop table bug16206;

set autocommit=0;

End of 5.0 tests

mysql-test/t/bdb_notembedded.test

0 → 100644
+38 −0
Original line number Diff line number Diff line 
-- source include/not_embedded.inc

-- source include/have_bdb.inc



#

# Bug #16206: Superfluous COMMIT event in binlog when updating BDB in autocommit mode

#

set autocommit=1;



let $VERSION=`select version()`;



reset master;

create table bug16206 (a int);

insert into bug16206 values(1);

start transaction;

insert into bug16206 values(2);

commit;

--replace_result $VERSION VERSION

--replace_column 1 f 2 n 5 n

show binlog events;

drop table bug16206;



reset master;

create table bug16206 (a int) engine=         bdb;

insert into bug16206 values(0);

insert into bug16206 values(1);

start transaction;

insert into bug16206 values(2);

commit;

insert into bug16206 values(3);

--replace_result $VERSION VERSION

--replace_column 1 f 2 n 5 n

show binlog events;

drop table bug16206;



set autocommit=0;





--echo End of 5.0 tests

ndb/include/kernel/signaldata/ScanTab.hpp

+27 −17
Original line number Diff line number Diff line
@@ -113,15 +113,15 @@ private: 
 z = Descending (TUX)      - 1  Bit 14

 x = Range Scan (TUX)      - 1  Bit 15

 b = Scan batch            - 10 Bit 16-25 (max 1023)

 d = Distribution key flag

 d = Distribution key flag - 1  Bit 26



           1111111111222222222233

 01234567890123456789012345678901

 ppppppppl hcktzxbbbbbbbbbb

 ppppppppl hcktzxbbbbbbbbbbd

*/



#define PARALLELL_SHIFT     (0)

#define PARALLELL_MASK      (255)

#define PARALLEL_SHIFT     (0)

#define PARALLEL_MASK      (255)



#define LOCK_MODE_SHIFT     (8)

#define LOCK_MODE_MASK      (1)
@@ -148,11 +148,12 @@ private: 
#define SCAN_BATCH_MASK  (1023)



#define SCAN_DISTR_KEY_SHIFT (26)

#define SCAN_DISTR_KEY_MASK (1)



inline

Uint8

ScanTabReq::getParallelism(const UintR & requestInfo){

  return (Uint8)((requestInfo >> PARALLELL_SHIFT) & PARALLELL_MASK);

  return (Uint8)((requestInfo >> PARALLEL_SHIFT) & PARALLEL_MASK);

}



inline
@@ -206,58 +207,65 @@ ScanTabReq::clearRequestInfo(UintR & requestInfo){ 
inline

void 

ScanTabReq::setParallelism(UintR & requestInfo, Uint32 type){

  ASSERT_MAX(type, PARALLELL_MASK, "ScanTabReq::setParallellism");

  requestInfo |= (type << PARALLELL_SHIFT);

  ASSERT_MAX(type, PARALLEL_MASK, "ScanTabReq::setParallelism");

  requestInfo= (requestInfo & ~(PARALLEL_MASK << PARALLEL_SHIFT)) |

               ((type & PARALLEL_MASK) << PARALLEL_SHIFT);

}



inline

void 

ScanTabReq::setLockMode(UintR & requestInfo, Uint32 mode){

  ASSERT_MAX(mode, LOCK_MODE_MASK,  "ScanTabReq::setLockMode");

  requestInfo |= (mode << LOCK_MODE_SHIFT);

  requestInfo= (requestInfo & ~(LOCK_MODE_MASK << LOCK_MODE_SHIFT)) |

               ((mode & LOCK_MODE_MASK) << LOCK_MODE_SHIFT);

}



inline

void 

ScanTabReq::setHoldLockFlag(UintR & requestInfo, Uint32 flag){

  ASSERT_BOOL(flag, "ScanTabReq::setHoldLockFlag");

  requestInfo |= (flag << HOLD_LOCK_SHIFT);

  requestInfo= (requestInfo & ~(HOLD_LOCK_MASK << HOLD_LOCK_SHIFT)) |

               ((flag & HOLD_LOCK_MASK) << HOLD_LOCK_SHIFT);

}



inline

void 

ScanTabReq::setReadCommittedFlag(UintR & requestInfo, Uint32 flag){

  ASSERT_BOOL(flag, "ScanTabReq::setReadCommittedFlag");

  requestInfo |= (flag << READ_COMMITTED_SHIFT);

  requestInfo= (requestInfo & ~(READ_COMMITTED_MASK << READ_COMMITTED_SHIFT)) |

               ((flag & READ_COMMITTED_MASK) << READ_COMMITTED_SHIFT);

}



inline

void 

ScanTabReq::setRangeScanFlag(UintR & requestInfo, Uint32 flag){

  ASSERT_BOOL(flag, "ScanTabReq::setRangeScanFlag");

  requestInfo |= (flag << RANGE_SCAN_SHIFT);

  requestInfo= (requestInfo & ~(RANGE_SCAN_MASK << RANGE_SCAN_SHIFT)) |

               ((flag & RANGE_SCAN_MASK) << RANGE_SCAN_SHIFT);

}



inline

void 

ScanTabReq::setDescendingFlag(UintR & requestInfo, Uint32 flag){

  ASSERT_BOOL(flag, "ScanTabReq::setDescendingFlag");

  requestInfo |= (flag << DESCENDING_SHIFT);

  requestInfo= (requestInfo & ~(DESCENDING_MASK << DESCENDING_SHIFT)) |

               ((flag & DESCENDING_MASK) << DESCENDING_SHIFT);

}



inline

void 

ScanTabReq::setTupScanFlag(UintR & requestInfo, Uint32 flag){

  ASSERT_BOOL(flag, "ScanTabReq::setTupScanFlag");

  requestInfo |= (flag << TUP_SCAN_SHIFT);

  requestInfo= (requestInfo & ~(TUP_SCAN_MASK << TUP_SCAN_SHIFT)) |

               ((flag & TUP_SCAN_MASK) << TUP_SCAN_SHIFT);

}



inline

void

ScanTabReq::setScanBatch(Uint32 & requestInfo, Uint32 flag){

  ASSERT_MAX(flag, SCAN_BATCH_MASK,  "ScanTabReq::setScanBatch");

  requestInfo &= ~(SCAN_BATCH_MASK << SCAN_BATCH_SHIFT);

  requestInfo |= (flag << SCAN_BATCH_SHIFT);

  requestInfo= (requestInfo & ~(SCAN_BATCH_MASK << SCAN_BATCH_SHIFT)) |

               ((flag & SCAN_BATCH_MASK) << SCAN_BATCH_SHIFT);

}



inline
@@ -270,7 +278,8 @@ inline 
void 

ScanTabReq::setKeyinfoFlag(UintR & requestInfo, Uint32 flag){

  ASSERT_BOOL(flag, "ScanTabReq::setKeyinfoFlag");

  requestInfo |= (flag << KEYINFO_SHIFT);

  requestInfo= (requestInfo & ~(KEYINFO_MASK << KEYINFO_SHIFT)) |

               ((flag & KEYINFO_MASK) << KEYINFO_SHIFT);

}



inline
@@ -283,7 +292,8 @@ inline 
void 

ScanTabReq::setDistributionKeyFlag(UintR & requestInfo, Uint32 flag){

  ASSERT_BOOL(flag, "ScanTabReq::setKeyinfoFlag");

  requestInfo |= (flag << SCAN_DISTR_KEY_SHIFT);

  requestInfo= (requestInfo & ~(SCAN_DISTR_KEY_MASK << SCAN_DISTR_KEY_SHIFT)) |

               ((flag & SCAN_DISTR_KEY_MASK) << SCAN_DISTR_KEY_SHIFT);

}



/**

ndb/include/ndbapi/NdbOperation.hpp

+2 −0
Original line number Diff line number Diff line
@@ -908,6 +908,8 @@ protected: 
  // get table or index key from prepared signals

  int getKeyFromTCREQ(Uint32* data, unsigned size);



  virtual void setReadLockMode(LockMode lockMode);



/******************************************************************************

 * These are the private variables that are defined in the operation objects.

 *****************************************************************************/

ndb/include/ndbapi/NdbScanOperation.hpp

+1 −0
Original line number Diff line number Diff line
@@ -212,6 +212,7 @@ protected: 
  int prepareSend(Uint32  TC_ConnectPtr, Uint64  TransactionId);

  int doSend(int ProcessorId);

  void checkForceSend(bool forceSend);

  virtual void setReadLockMode(LockMode lockMode);



  virtual void setErrorCode(int aErrorCode);

  virtual void setErrorCodeAbort(int aErrorCode);