~ignacio-nin/percona-server/5.1-issue26684

# name       : sql_no_fcache.patch

# introduced : 12

# maintainer : Oleg

#

#!!! notice !!!

# Any small change to this file in the main branch

# should be done or reviewed by the maintainer!

diff -ruN a/client/mysqldump.c b/client/mysqldump.c

--- a/client/mysqldump.c	2010-07-28 16:47:58.264067653 +0400

+++ b/client/mysqldump.c	2010-07-28 16:47:59.604985656 +0400

@@ -132,6 +132,8 @@

 #endif

 static uint opt_protocol= 0;

+static my_bool server_supports_sql_no_fcache= FALSE;

+

 /*

 Dynamic_string wrapper functions. In this file use these

 wrappers, they will terminate the process if there is

@@ -1512,6 +1514,17 @@

     /* Don't switch charsets for 4.1 and earlier.  (bug#34192). */

     server_supports_switching_charsets= FALSE;

   } 

+  

+  /* Check to see if we support SQL_NO_FCACHE on this server. */ 

+  if (mysql_query(mysql, "SELECT SQL_NO_FCACHE NOW()") == 0)

+  {

+    MYSQL_RES *res = mysql_store_result(mysql);

+    if (res)

+    {

+      mysql_free_result(res);

+    }

+    server_supports_sql_no_fcache= TRUE;

+  }

   /*

     As we're going to set SQL_MODE, it would be lost on reconnect, so we

     cannot reconnect.

@@ -3175,7 +3188,12 @@

     /* now build the query string */

-    dynstr_append_checked(&query_string, "SELECT /*!40001 SQL_NO_CACHE */ * INTO OUTFILE '");

+    dynstr_append_checked(&query_string, "SELECT /*!40001 SQL_NO_CACHE */ ");

+    if (server_supports_sql_no_fcache)

+    {

+      dynstr_append_checked(&query_string, "/*!50084 SQL_NO_FCACHE */ ");

+    }

+    dynstr_append_checked(&query_string, "* INTO OUTFILE '");

     dynstr_append_checked(&query_string, filename);

     dynstr_append_checked(&query_string, "'");

@@ -3225,7 +3243,12 @@

       check_io(md_result_file);

     }

-    dynstr_append_checked(&query_string, "SELECT /*!40001 SQL_NO_CACHE */ * FROM ");

+    dynstr_append_checked(&query_string, "SELECT /*!40001 SQL_NO_CACHE */ ");

+    if (server_supports_sql_no_fcache)

+    {

+      dynstr_append_checked(&query_string, "/*!50084 SQL_NO_FCACHE */ ");

+    }

+    dynstr_append_checked(&query_string, "* FROM ");

     dynstr_append_checked(&query_string, result_table);

     if (where)

diff -ruN a/include/flashcache_ioctl.h b/include/flashcache_ioctl.h

--- a/include/flashcache_ioctl.h	1970-01-01 03:00:00.000000000 +0300

+++ b/include/flashcache_ioctl.h	2010-07-28 16:47:59.744079911 +0400

@@ -0,0 +1,53 @@

+/****************************************************************************

+ *  flashcache_ioctl.h

+ *  FlashCache: Device mapper target for block-level disk caching

+ *

+ *  Copyright 2010 Facebook, Inc.

+ *  Author: Mohan Srinivasan (mohan@facebook.com)

+ *

+ *  Based on DM-Cache:

+ *   Copyright (C) International Business Machines Corp., 2006

+ *   Author: Ming Zhao (mingzhao@ufl.edu)

+ *

+ *  This program is free software; you can redistribute it and/or modify

+ *  it under the terms of the GNU General Public License as published by

+ *  the Free Software Foundation; under version 2 of the License.

+ *

+ *  This program is distributed in the hope that it will be useful,

+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of

+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+ *  GNU General Public License for more details.

+ *

+ * You should have received a copy of the GNU General Public License

+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.

+ ****************************************************************************/

+

+#ifndef FLASHCACHE_IOCTL_H

+#define FLASHCACHE_IOCTL_H

+

+#include <linux/types.h>

+

+#define FLASHCACHE_IOCTL 0xfe

+

+enum {

+       FLASHCACHEADDNCPID_CMD=200,

+       FLASHCACHEDELNCPID_CMD,

+       FLASHCACHEDELNCALL_CMD,

+       FLASHCACHEADDWHITELIST_CMD,

+       FLASHCACHEDELWHITELIST_CMD,

+       FLASHCACHEDELWHITELISTALL_CMD,

+};

+

+#define FLASHCACHEADDNCPID     _IOW(FLASHCACHE_IOCTL, FLASHCACHEADDNCPID_CMD, pid_t)

+#define FLASHCACHEDELNCPID     _IOW(FLASHCACHE_IOCTL, FLASHCACHEDELNCPID_CMD, pid_t)

+#define FLASHCACHEDELNCALL     _IOW(FLASHCACHE_IOCTL, FLASHCACHEDELNCALL_CMD, pid_t)

+

+#define FLASHCACHEADDBLACKLIST         FLASHCACHEADDNCPID

+#define FLASHCACHEDELBLACKLIST         FLASHCACHEDELNCPID

+#define FLASHCACHEDELALLBLACKLIST      FLASHCACHEDELNCALL

+

+#define FLASHCACHEADDWHITELIST         _IOW(FLASHCACHE_IOCTL, FLASHCACHEADDWHITELIST_CMD, pid_t)

+#define FLASHCACHEDELWHITELIST         _IOW(FLASHCACHE_IOCTL, FLASHCACHEDELWHITELIST_CMD, pid_t)

+#define FLASHCACHEDELALLWHITELIST      _IOW(FLASHCACHE_IOCTL, FLASHCACHEDELWHITELISTALL_CMD, pid_t)

+

+#endif

diff -ruN a/mysql-test/r/mysqldump.result b/mysql-test/r/mysqldump.result

--- a/mysql-test/r/mysqldump.result	2010-07-28 16:47:58.334083833 +0400

+++ b/mysql-test/r/mysqldump.result	2010-07-28 16:48:14.805318437 +0400

@@ -1832,7 +1832,7 @@

 # Bug#21288 mysqldump segmentation fault when using --where

 #

 create table t1 (a int);

-mysqldump: Couldn't execute 'SELECT /*!40001 SQL_NO_CACHE */ * FROM `t1` WHERE xx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx': You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' at line 1 (1064)

+mysqldump: Couldn't execute 'SELECT /*!40001 SQL_NO_CACHE */ /*!50084 SQL_NO_FCACHE */ * FROM `t1` WHERE xx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx': You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' at line 1 (1064)

 mysqldump: Got error: 1064: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' at line 1 when retrieving data from server

 /*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;

diff -ruN a/patch_info/sql_no_fcache.info b/patch_info/sql_no_fcache.info

--- a/patch_info/sql_no_fcache.info	1970-01-01 03:00:00.000000000 +0300

+++ b/patch_info/sql_no_fcache.info	2010-07-28 16:47:59.915439165 +0400

@@ -0,0 +1,6 @@

+File=sql_no_fcache.patch

+Name=Support for flashcache including the SQL_NO_FCACHE option that prevents blocks from being cached during a query.

+Version=1.0

+Author=Facebook

+License=GPL

+Comment=

diff -ruN a/sql/lex.h b/sql/lex.h

--- a/sql/lex.h	2010-07-28 16:47:58.575318748 +0400

+++ b/sql/lex.h	2010-07-28 16:48:00.134078469 +0400

@@ -500,6 +500,7 @@

   { "SQL_CACHE",        SYM(SQL_CACHE_SYM)},

   { "SQL_CALC_FOUND_ROWS", SYM(SQL_CALC_FOUND_ROWS)},

   { "SQL_NO_CACHE",	SYM(SQL_NO_CACHE_SYM)},

+  { "SQL_NO_FCACHE",   SYM(SQL_NO_FCACHE_SYM)},

   { "SQL_SMALL_RESULT", SYM(SQL_SMALL_RESULT)},

   { "SQL_THREAD",	SYM(SQL_THREAD)},

   { "SQL_TSI_FRAC_SECOND", SYM(FRAC_SECOND_SYM)},

diff -ruN a/sql/mysqld.cc b/sql/mysqld.cc

--- a/sql/mysqld.cc	2010-07-28 16:47:58.565318871 +0400

+++ b/sql/mysqld.cc	2010-07-28 16:48:03.004544367 +0400

@@ -45,6 +45,11 @@

 #define OPT_NDB_SHM_DEFAULT 0

 #endif

 #endif

+#if defined(__linux__)

+#include <mntent.h>

+#include <sys/statfs.h>

+#include "flashcache_ioctl.h"

+#endif//__linux__

 #ifndef DEFAULT_SKIP_THREAD_PRIORITY

 #define DEFAULT_SKIP_THREAD_PRIORITY 0

@@ -593,6 +598,11 @@

 ulong max_connections, max_connect_errors;

 uint  max_user_connections= 0;

 ulonglong denied_connections = 0;

+

+/* flashcache */

+int cachedev_fd;

+my_bool cachedev_enabled= FALSE;

+

 /**

   Limit of the total number of prepared statements in the server.

   Is necessary to protect the server against out-of-memory attacks.

@@ -4391,6 +4401,97 @@

 }

 #endif//DBUG_OFF

+#if defined(__linux__)

+/*

+ * Auto detect if we support flash cache on the host system.

+ * This needs to be called before we setuid away from root

+ * to avoid permission problems on opening the device node.

+ */

+static void init_cachedev(void)

+{

+  struct statfs stfs_data_home_dir;

+  struct statfs stfs;

+  struct mntent *ent;

+  pid_t pid = getpid();

+  FILE *mounts;

+  char *error_message= NULL;

+

+  // disabled by default

+  cachedev_fd = -1;

+  cachedev_enabled= FALSE;

+

+  if (!mysql_data_home)

+  {

+    error_message= "mysql_data_home not set";

+    goto epilogue;

+  }

+

+  if (statfs(mysql_data_home, &stfs_data_home_dir) < 0)

+  {

+    error_message= "statfs failed";

+    goto epilogue;

+  }

+

+  mounts = setmntent("/etc/mtab", "r");

+  if (mounts == NULL)

+  {

+    error_message= "setmntent failed";

+    goto epilogue;

+  }

+

+  while ((ent = getmntent(mounts)) != NULL)

+  {

+    if (statfs(ent->mnt_dir, &stfs) < 0)

+      continue;

+    if (memcmp(&stfs.f_fsid, &stfs_data_home_dir.f_fsid, sizeof(fsid_t)) == 0)

+      break;

+  }

+  endmntent(mounts);

+

+  if (ent == NULL)

+  {

+    error_message= "getmntent loop failed";

+    goto epilogue;

+  }

+

+  cachedev_fd = open(ent->mnt_fsname, O_RDONLY);

+  if (cachedev_fd < 0)

+  {

+    error_message= "open flash device failed";

+    goto epilogue;

+  }

+

+  /* cleanup previous whitelistings */

+  if (ioctl(cachedev_fd, FLASHCACHEDELALLWHITELIST, &pid) < 0)

+  {

+    close(cachedev_fd);

+    cachedev_fd = -1;

+    error_message= "ioctl failed";

+  } else {

+    ioctl(cachedev_fd, FLASHCACHEADDWHITELIST, &pid);

+  }

+

+epilogue:

+  sql_print_information("Flashcache bypass: %s",

+      (cachedev_fd > 0) ? "enabled" : "disabled");

+  if (error_message)

+    sql_print_information("Flashcache setup error is : %s\n", error_message);

+  else

+    cachedev_enabled= TRUE;

+

+}

+

+static void cleanup_cachedev(void)

+{

+  pid_t pid = getpid();

+

+  if (cachedev_enabled) {

+    ioctl(cachedev_fd, FLASHCACHEDELWHITELIST, &pid);

+    close(cachedev_fd);

+    cachedev_fd = -1;

+  }

+}

+#endif//__linux__

 #ifdef __WIN__

 int win_main(int argc, char **argv)

@@ -4495,6 +4596,10 @@

   test_lc_time_sz();

 #endif

+#if defined(__linux__)

+  init_cachedev();

+#endif//__linux__

+

   /*

     We have enough space for fiddling with the argv, continue

   */

@@ -4696,6 +4801,10 @@

   clean_up_mutexes();

   my_end(opt_endinfo ? MY_CHECK_ERROR | MY_GIVE_INFO : 0);

+#if defined(__linux__)

+  cleanup_cachedev();

+#endif//__linux__

+

   exit(0);

   return(0);					/* purecov: deadcode */

 }

@@ -7853,6 +7962,7 @@

   {"Delayed_errors",           (char*) &delayed_insert_errors,  SHOW_LONG},

   {"Delayed_insert_threads",   (char*) &delayed_insert_threads, SHOW_LONG_NOFLUSH},

   {"Delayed_writes",           (char*) &delayed_insert_writes,  SHOW_LONG},

+  {"Flashcache_enabled",       (char*) &cachedev_enabled,       SHOW_BOOL },

   {"Flush_commands",           (char*) &refresh_version,        SHOW_LONG_NOFLUSH},

   {"Handler_commit",           (char*) offsetof(STATUS_VAR, ha_commit_count), SHOW_LONG_STATUS},

   {"Handler_delete",           (char*) offsetof(STATUS_VAR, ha_delete_count), SHOW_LONG_STATUS},

diff -ruN a/sql/mysql_priv.h b/sql/mysql_priv.h

--- a/sql/mysql_priv.h	2010-07-28 16:47:58.575318748 +0400

+++ b/sql/mysql_priv.h	2010-07-28 16:48:05.505952089 +0400

@@ -819,6 +819,8 @@

 */

 extern ulong server_id, concurrency;

+/* flashcache */

+extern int cachedev_fd;

 typedef my_bool (*qc_engine_callback)(THD *thd, char *table_key,

                                       uint key_length,

diff -ruN a/sql/sql_lex.cc b/sql/sql_lex.cc

--- a/sql/sql_lex.cc	2010-07-28 16:47:58.555318714 +0400

+++ b/sql/sql_lex.cc	2010-07-28 16:48:07.794069239 +0400

@@ -306,6 +306,7 @@

   lex->describe= 0;

   lex->subqueries= FALSE;

   lex->context_analysis_only= 0;

+  lex->disable_flashcache= FALSE;

   lex->derived_tables= 0;

   lex->lock_option= TL_READ;

   lex->safe_to_cache_query= 1;

diff -ruN a/sql/sql_lex.h b/sql/sql_lex.h

--- a/sql/sql_lex.h	2010-07-28 16:47:58.575318748 +0400

+++ b/sql/sql_lex.h	2010-07-28 16:48:08.405691834 +0400

@@ -1722,6 +1722,7 @@

   uint8 context_analysis_only;

   bool safe_to_cache_query;

+  bool disable_flashcache;

   bool subqueries, ignore;

   st_parsing_options parsing_options;

   Alter_info alter_info;

diff -ruN a/sql/sql_select.cc b/sql/sql_select.cc

--- a/sql/sql_select.cc	2010-07-28 16:47:58.555318714 +0400

+++ b/sql/sql_select.cc	2010-07-28 16:48:13.414069437 +0400

@@ -37,6 +37,12 @@

 #include <hash.h>

 #include <ft_global.h>

+#include <sys/syscall.h>

+#include <sys/ioctl.h>

+#if defined(__linux__)

+#include "flashcache_ioctl.h"

+#endif//__linux__

+

 const char *join_type_str[]={ "UNKNOWN","system","const","eq_ref","ref",

 			      "MAYBE_REF","ALL","range","index","fulltext",

 			      "ref_or_null","unique_subquery","index_subquery",

@@ -239,9 +245,20 @@

                    ulong setup_tables_done_option)

 {

   bool res;

+#if defined(__linux__)

+  pid_t pid;

+#endif

   register SELECT_LEX *select_lex = &lex->select_lex;

   DBUG_ENTER("handle_select");

+#if defined(__linux__)

+  if(lex->disable_flashcache && cachedev_fd > 0)

+  {

+    pid = syscall(SYS_gettid);

+    ioctl(cachedev_fd, FLASHCACHEADDNCPID, &pid);

+  }

+#endif//__linux__

+ 

   if (select_lex->master_unit()->is_union() || 

       select_lex->master_unit()->fake_select_lex)

     res= mysql_union(thd, lex, result, &lex->unit, setup_tables_done_option);

@@ -274,6 +291,12 @@

   if (unlikely(res))

     result->abort();

+#if defined(__linux__)

+  if (lex->disable_flashcache && cachedev_fd > 0)

+  {

+    ioctl(cachedev_fd, FLASHCACHEDELNCPID, &pid);

+  }

+#endif//__linux__ 

   DBUG_RETURN(res);

 }

diff -ruN a/sql/sql_yacc.yy b/sql/sql_yacc.yy

--- a/sql/sql_yacc.yy	2010-07-28 16:47:58.565318871 +0400

+++ b/sql/sql_yacc.yy	2010-07-28 16:48:14.205317990 +0400

@@ -1164,6 +1164,7 @@

 %token  SQL_CACHE_SYM

 %token  SQL_CALC_FOUND_ROWS

 %token  SQL_NO_CACHE_SYM

+%token  SQL_NO_FCACHE_SYM

 %token  SQL_SMALL_RESULT

 %token  SQL_SYM                       /* SQL-2003-R */

 %token  SQL_THREAD

@@ -6752,6 +6753,10 @@

             Lex->select_lex.options&= ~OPTION_TO_QUERY_CACHE;

             Lex->select_lex.sql_cache= SELECT_LEX::SQL_NO_CACHE;

           }

+	| SQL_NO_FCACHE_SYM

+	  {

+	    Lex->disable_flashcache= TRUE;

+	  }

         | SQL_CACHE_SYM

           {

             /*