Many files:

  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x


sql/ha_innodb.cc:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/sql_class.cc:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/sql_parse.cc:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/sql_table.cc:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/ha_innodb.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/handler.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/lex.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/mysql_priv.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/sql_class.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/sql_lex.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
sql/sql_yacc.yy:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/ha/ha0ha.c:
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x
innobase/ha/hash0hash.c:
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x
innobase/buf/buf0buf.c:
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x
innobase/buf/buf0flu.c:
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x
innobase/buf/buf0lru.c:
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x
innobase/buf/buf0rea.c:
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x
innobase/btr/btr0btr.c:
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x
innobase/btr/btr0sea.c:
  Track crash in buf_LRU_block_remove_hashed_page + 1807 reported in MySQL-3.23.5x
innobase/fil/fil0fil.c:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/include/buf0buf.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/include/ha0ha.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/include/hash0hash.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/include/row0mysql.h:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/include/buf0buf.ic:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/include/ha0ha.ic:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/include/ibuf0ibuf.ic:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/page/page0page.c:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/row/row0mysql.c:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/row/row0purge.c:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/row/row0uins.c:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE
innobase/row/row0umod.c:
  ALTER TABLE ... DISCARD/IMPORT TABLESPACE

32 files changed, 424 insertions, 118 deletions

diff --git a/innobase/btr/btr0btr.c b/innobase/btr/btr0btr.c
index 1af9336ce72..3d11cbe1748 100644
--- a/innobase/btr/btr0btr.c
+++ b/innobase/btr/btr0btr.c
@@ -426,7 +426,8 @@ btr_page_free_for_ibuf(
 	flst_add_first(root + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST,
 		       page + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST_NODE, mtr);
 
-	ut_ad(flst_validate(root + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST, mtr));
+	ut_ad(flst_validate(root + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST,
+									mtr));
 }
 
 /******************************************************************
diff --git a/innobase/btr/btr0sea.c b/innobase/btr/btr0sea.c
index 8dbffd82a20..e49ee15f5ea 100644
--- a/innobase/btr/btr0sea.c
+++ b/innobase/btr/btr0sea.c
@@ -776,8 +776,8 @@ btr_search_guess_on_hash(
 		goto failure;
 	}
 
-	ut_ad(block->state == BUF_BLOCK_FILE_PAGE);
-	ut_ad(page_rec_is_user_rec(rec));	
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(page_rec_is_user_rec(rec));	
 
 	btr_cur_position(index, rec, cursor);
 
diff --git a/innobase/buf/buf0buf.c b/innobase/buf/buf0buf.c
index 1e1c6b25c1d..b403cc4df0d 100644
--- a/innobase/buf/buf0buf.c
+++ b/innobase/buf/buf0buf.c
@@ -468,6 +468,11 @@ buf_block_init(
 
 	block->check_index_page_at_flush = FALSE;
 
+	block->in_free_list = FALSE;
+	block->in_LRU_list = FALSE;
+
+	block->n_pointers = 0;
+
 	rw_lock_create(&(block->lock));
 	ut_ad(rw_lock_validate(&(block->lock)));
 	
@@ -687,6 +692,7 @@ buf_pool_init(
 		}
 
 		UT_LIST_ADD_LAST(free, buf_pool->free, block);
+		block->in_free_list = TRUE;
 	}
 
 	mutex_exit(&(buf_pool->mutex));
@@ -830,7 +836,7 @@ buf_page_make_young(
 
 	block = buf_block_align(frame);
 
-	ut_ad(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
 
 	buf_LRU_make_block_young(block);
 
@@ -845,7 +851,7 @@ buf_block_free(
 /*===========*/
 	buf_block_t*	block)	/* in, own: block to be freed */
 {
-	ut_ad(block->state != BUF_BLOCK_FILE_PAGE);
+	ut_a(block->state != BUF_BLOCK_FILE_PAGE);
 
 	mutex_enter(&(buf_pool->mutex));
 
@@ -1109,6 +1115,8 @@ loop:
 		goto loop;
 	}
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 	must_read = FALSE;
 	
 	if (block->io_fix == BUF_IO_READ) {
@@ -1407,6 +1415,8 @@ buf_page_get_known_nowait(
 		return(FALSE);
 	}
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 #ifdef UNIV_SYNC_DEBUG
 	buf_block_buf_fix_inc_debug(block, file, line);
 #else
@@ -1517,7 +1527,7 @@ buf_page_init(
 	buf_block_t*	block)	/* in: block to init */
 {
 	ut_ad(mutex_own(&(buf_pool->mutex)));
-	ut_ad(block->state == BUF_BLOCK_READY_FOR_USE);
+	ut_a(block->state != BUF_BLOCK_FILE_PAGE);
 
 	/* Set the state of the block */
 	block->magic_n		= BUF_BLOCK_MAGIC_N;
@@ -1533,6 +1543,18 @@ buf_page_init(
 	
 	/* Insert into the hash table of file pages */
 
+        if (buf_page_hash_get(space, offset)) {
+                fprintf(stderr,
+"InnoDB: Error: page %lu %lu already found from the hash table\n", space,
+							offset);
+                buf_print();
+                buf_LRU_print();
+                buf_validate();
+                buf_LRU_validate();
+
+                ut_a(0);
+        }
+
 	HASH_INSERT(buf_block_t, hash, buf_pool->page_hash,
 				buf_page_address_fold(space, offset), block);
 
@@ -1605,7 +1627,7 @@ buf_page_init_for_read(
 	
 	block = buf_block_alloc();
 
-	ut_ad(block);
+	ut_a(block);
 
 	mutex_enter(&(buf_pool->mutex));
 
@@ -1769,6 +1791,8 @@ buf_page_io_complete(
 	
 	ut_ad(block);
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 	io_type = block->io_fix;
 
 	if (io_type == BUF_IO_READ) {
diff --git a/innobase/buf/buf0flu.c b/innobase/buf/buf0flu.c
index 3f8022f36bc..27a1829942d 100644
--- a/innobase/buf/buf0flu.c
+++ b/innobase/buf/buf0flu.c
@@ -50,6 +50,8 @@ buf_flush_insert_into_flush_list(
 {
 	ut_ad(mutex_own(&(buf_pool->mutex)));
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 	ut_ad((UT_LIST_GET_FIRST(buf_pool->flush_list) == NULL)
 	      || (ut_dulint_cmp(
 			(UT_LIST_GET_FIRST(buf_pool->flush_list))
@@ -131,7 +133,7 @@ buf_flush_ready_for_flush(
 	ulint		flush_type)/* in: BUF_FLUSH_LRU or BUF_FLUSH_LIST */
 {
 	ut_ad(mutex_own(&(buf_pool->mutex)));
-	ut_ad(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
 
 	if ((ut_dulint_cmp(block->oldest_modification, ut_dulint_zero) > 0)
 	    					&& (block->io_fix == 0)) {
@@ -163,6 +165,8 @@ buf_flush_write_complete(
 	ut_ad(block);
 	ut_ad(mutex_own(&(buf_pool->mutex)));
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 	block->oldest_modification = ut_dulint_zero;
 
 	UT_LIST_REMOVE(flush_list, buf_pool->flush_list, block);
@@ -282,6 +286,8 @@ buf_flush_buffered_writes(void)
 	for (i = 0; i < trx_doublewrite->first_free; i++) {
 		block = trx_doublewrite->buf_block_arr[i];
 
+		ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 		fil_io(OS_FILE_WRITE | OS_AIO_SIMULATED_WAKE_LATER,
 			FALSE, block->space, block->offset, 0, UNIV_PAGE_SIZE,
 		 			(void*)block->frame, (void*)block);
@@ -321,6 +327,8 @@ buf_flush_post_to_doublewrite_buf(
 try_again:
 	mutex_enter(&(trx_doublewrite->mutex));
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 	if (trx_doublewrite->first_free
 				>= 2 * TRX_SYS_DOUBLEWRITE_BLOCK_SIZE) {
 		mutex_exit(&(trx_doublewrite->mutex));
@@ -395,6 +403,8 @@ buf_flush_write_block_low(
 /*======================*/
 	buf_block_t*	block)	/* in: buffer block to write */
 {
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 #ifdef UNIV_IBUF_DEBUG
 	ut_a(ibuf_count_get(block->space, block->offset) == 0);
 #endif
@@ -443,7 +453,7 @@ buf_flush_try_page(
 
 	block = buf_page_hash_get(space, offset);
 
-	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(!block || block->state == BUF_BLOCK_FILE_PAGE);
 
 	if (flush_type == BUF_FLUSH_LIST
 	    && block && buf_flush_ready_for_flush(block, flush_type)) {
@@ -635,6 +645,7 @@ buf_flush_try_neighbors(
 	for (i = low; i < high; i++) {
 
 		block = buf_page_hash_get(space, i);
+		ut_a(!block || block->state == BUF_BLOCK_FILE_PAGE);
 
 		if (block && flush_type == BUF_FLUSH_LRU && i != offset
 		    && !block->old) {
@@ -703,10 +714,10 @@ buf_flush_batch(
 	ulint		offset;
 	ibool		found;
 	
-	ut_ad((flush_type == BUF_FLUSH_LRU) || (flush_type == BUF_FLUSH_LIST)); 
-	ut_ad((flush_type != BUF_FLUSH_LIST) ||
-					sync_thread_levels_empty_gen(TRUE));
-
+	ut_ad((flush_type == BUF_FLUSH_LRU)
+					|| (flush_type == BUF_FLUSH_LIST)); 
+	ut_ad((flush_type != BUF_FLUSH_LIST)
+					|| sync_thread_levels_empty_gen(TRUE));
 	mutex_enter(&(buf_pool->mutex));
 
 	if ((buf_pool->n_flush[flush_type] > 0)
@@ -737,7 +748,6 @@ buf_flush_batch(
 			ut_ad(flush_type == BUF_FLUSH_LIST);
 
 			block = UT_LIST_GET_LAST(buf_pool->flush_list);
-
 			if (!block
 			    || (ut_dulint_cmp(block->oldest_modification,
 			    				lsn_limit) >= 0)) {
@@ -756,6 +766,7 @@ buf_flush_batch(
 		function a pointer to a block in the list! */
 
 	    	while ((block != NULL) && !found) {
+			ut_a(block->state == BUF_BLOCK_FILE_PAGE);
 
 			if (buf_flush_ready_for_flush(block, flush_type)) {
 
@@ -781,7 +792,6 @@ buf_flush_batch(
 			} else if (flush_type == BUF_FLUSH_LRU) {
 
 				block = UT_LIST_GET_PREV(LRU, block);
-
 			} else {
 				ut_ad(flush_type == BUF_FLUSH_LIST);
 
diff --git a/innobase/buf/buf0lru.c b/innobase/buf/buf0lru.c
index 5d48d460745..55a5ecbeba5 100644
--- a/innobase/buf/buf0lru.c
+++ b/innobase/buf/buf0lru.c
@@ -82,6 +82,8 @@ scan_again:
 	block = UT_LIST_GET_LAST(buf_pool->LRU);
 
 	while (block != NULL) {
+	        ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 		if (block->space == id
 		    && (block->buf_fix_count > 0 || block->io_fix != 0)) {
 
@@ -199,19 +201,16 @@ buf_LRU_search_and_free_block(
 	mutex_enter(&(buf_pool->mutex));
 	
 	freed = FALSE;
-	
 	block = UT_LIST_GET_LAST(buf_pool->LRU);
 
 	while (block != NULL) {
-
+	        ut_a(block->in_LRU_list);
 		if (buf_flush_ready_for_replace(block)) {
-
 			if (buf_debug_prints) {
 				printf(
 				"Putting space %lu page %lu to free list\n",
 					block->space, block->offset);
 			}
-			
 			buf_LRU_block_remove_hashed_page(block);
 
 			mutex_exit(&(buf_pool->mutex));
@@ -223,25 +222,21 @@ buf_LRU_search_and_free_block(
 			if (block->frame) {
 				btr_search_drop_page_hash_index(block->frame);
 			}
-
 			mutex_enter(&(buf_pool->mutex));
 
 			ut_a(block->buf_fix_count == 0);
 
 			buf_LRU_block_free_hashed_page(block);
-
 			freed = TRUE;
 
 			break;
 		}
-
 		block = UT_LIST_GET_PREV(LRU, block);
 		distance++;
 
 		if (!freed && n_iterations <= 10
 		    && distance > 100 + (n_iterations * buf_pool->curr_size)
 					/ 10) {
-
 			buf_pool->LRU_flush_ended = 0;
 
 			mutex_exit(&(buf_pool->mutex));
@@ -249,15 +244,12 @@ buf_LRU_search_and_free_block(
 			return(FALSE);
 		}
 	}
-
 	if (buf_pool->LRU_flush_ended > 0) {
 		buf_pool->LRU_flush_ended--;
 	}
- 
-	if (!freed) {
+ 	if (!freed) {
 		buf_pool->LRU_flush_ended = 0;
 	}
-
 	mutex_exit(&(buf_pool->mutex));
 	
 	return(freed);
@@ -355,7 +347,11 @@ loop:
 	if (UT_LIST_GET_LEN(buf_pool->free) > 0) {
 		
 		block = UT_LIST_GET_FIRST(buf_pool->free);
+		ut_a(block->in_free_list);
 		UT_LIST_REMOVE(free, buf_pool->free, block);
+		block->in_free_list = FALSE;
+		ut_a(block->state != BUF_BLOCK_FILE_PAGE);
+	        ut_a(!block->in_LRU_list);
 
 		if (srv_use_awe) {
 			if (block->frame) {
@@ -466,7 +462,7 @@ buf_LRU_old_adjust_len(void)
 	ulint	old_len;
 	ulint	new_len;
 
-	ut_ad(buf_pool->LRU_old);
+	ut_a(buf_pool->LRU_old);
 	ut_ad(mutex_own(&(buf_pool->mutex)));
 	ut_ad(3 * (BUF_LRU_OLD_MIN_LEN / 8) > BUF_LRU_OLD_TOLERANCE + 5);
 
@@ -474,6 +470,8 @@ buf_LRU_old_adjust_len(void)
 		old_len = buf_pool->LRU_old_len;
 		new_len = 3 * (UT_LIST_GET_LEN(buf_pool->LRU) / 8);
 
+		ut_a(buf_pool->LRU_old->in_LRU_list);
+
 		/* Update the LRU_old pointer if necessary */
 	
 		if (old_len < new_len - BUF_LRU_OLD_TOLERANCE) {
@@ -490,7 +488,7 @@ buf_LRU_old_adjust_len(void)
 							buf_pool->LRU_old);
 			buf_pool->LRU_old_len--;
 		} else {
-			ut_ad(buf_pool->LRU_old); /* Check that we did not
+			ut_a(buf_pool->LRU_old); /* Check that we did not
 						fall out of the LRU list */
 			return;
 		}
@@ -498,9 +496,8 @@ buf_LRU_old_adjust_len(void)
 }
 
 /***********************************************************************
-Initializes the old blocks pointer in the LRU list.
-This function should be called when the LRU list grows to
-BUF_LRU_OLD_MIN_LEN length. */
+Initializes the old blocks pointer in the LRU list. This function should be
+called when the LRU list grows to BUF_LRU_OLD_MIN_LEN length. */
 static
 void
 buf_LRU_old_init(void)
@@ -508,7 +505,7 @@ buf_LRU_old_init(void)
 {
 	buf_block_t*	block;
 
-	ut_ad(UT_LIST_GET_LEN(buf_pool->LRU) == BUF_LRU_OLD_MIN_LEN);
+	ut_a(UT_LIST_GET_LEN(buf_pool->LRU) == BUF_LRU_OLD_MIN_LEN);
 
 	/* We first initialize all blocks in the LRU list as old and then use
 	the adjust function to move the LRU_old pointer to the right
@@ -517,6 +514,8 @@ buf_LRU_old_init(void)
 	block = UT_LIST_GET_FIRST(buf_pool->LRU);
 
 	while (block != NULL) {
+		ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+	        ut_a(block->in_LRU_list);
 		block->old = TRUE;
 		block = UT_LIST_GET_NEXT(LRU, block);
 	}
@@ -539,6 +538,9 @@ buf_LRU_remove_block(
 	ut_ad(block);
 	ut_ad(mutex_own(&(buf_pool->mutex)));
 		
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(block->in_LRU_list);
+
 	/* If the LRU_old pointer is defined and points to just this block,
 	move it backward one step */
 
@@ -552,11 +554,12 @@ buf_LRU_remove_block(
 		(buf_pool->LRU_old)->old = TRUE;
 
 		buf_pool->LRU_old_len++;
-		ut_ad(buf_pool->LRU_old);
+		ut_a(buf_pool->LRU_old);
 	}
 
 	/* Remove the block from the LRU list */
 	UT_LIST_REMOVE(LRU, buf_pool->LRU, block);
+	block->in_LRU_list = FALSE;
 
 	if (srv_use_awe && block->frame) {
 		/* Remove from the list of mapped pages */
@@ -599,6 +602,8 @@ buf_LRU_add_block_to_end_low(
 	ut_ad(block);
 	ut_ad(mutex_own(&(buf_pool->mutex)));
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 	block->old = TRUE;
 
 	last_block = UT_LIST_GET_LAST(buf_pool->LRU);
@@ -609,7 +614,9 @@ buf_LRU_add_block_to_end_low(
 		block->LRU_position = buf_pool_clock_tic();
 	}			
 
+	ut_a(!block->in_LRU_list);
 	UT_LIST_ADD_LAST(LRU, buf_pool->LRU, block);
+	block->in_LRU_list = TRUE;
 
 	if (srv_use_awe && block->frame) {
 		/* Add to the list of mapped pages */
@@ -658,6 +665,9 @@ buf_LRU_add_block_low(
 	ut_ad(block);
 	ut_ad(mutex_own(&(buf_pool->mutex)));
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(!block->in_LRU_list);
+
 	block->old = old;
 	cl = buf_pool_clock_tic();
 
@@ -687,6 +697,8 @@ buf_LRU_add_block_low(
 		block->LRU_position = (buf_pool->LRU_old)->LRU_position;
 	}
 
+	block->in_LRU_list = TRUE;
+
 	if (UT_LIST_GET_LEN(buf_pool->LRU) > BUF_LRU_OLD_MIN_LEN) {
 
 		ut_ad(buf_pool->LRU_old);
@@ -755,9 +767,12 @@ buf_LRU_block_free_non_file_page(
 	ut_ad(mutex_own(&(buf_pool->mutex)));
 	ut_ad(block);
 	
-	ut_ad((block->state == BUF_BLOCK_MEMORY)
+	ut_a((block->state == BUF_BLOCK_MEMORY)
 	      || (block->state == BUF_BLOCK_READY_FOR_USE));
 
+	ut_a(block->n_pointers == 0);
+	ut_a(!block->in_free_list);
+
 	block->state = BUF_BLOCK_NOT_USED;
 
 #ifdef UNIV_DEBUG	
@@ -765,6 +780,7 @@ buf_LRU_block_free_non_file_page(
 	memset(block->frame, '\0', UNIV_PAGE_SIZE);
 #endif	
 	UT_LIST_ADD_FIRST(free, buf_pool->free, block);
+	block->in_free_list = TRUE;
 
 	if (srv_use_awe && block->frame) {
 		/* Add to the list of mapped pages */
@@ -788,8 +804,7 @@ buf_LRU_block_remove_hashed_page(
 	ut_ad(mutex_own(&(buf_pool->mutex)));
 	ut_ad(block);
 	
-	ut_ad(block->state == BUF_BLOCK_FILE_PAGE);
-
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
 	ut_a(block->io_fix == 0);
 	ut_a(block->buf_fix_count == 0);
 	ut_a(ut_dulint_cmp(block->oldest_modification, ut_dulint_zero) == 0);
@@ -802,6 +817,28 @@ buf_LRU_block_remove_hashed_page(
 	
  	buf_block_modify_clock_inc(block);
 		
+        if (block != buf_page_hash_get(block->space, block->offset)) {
+                fprintf(stderr,
+"InnoDB: Error: page %lu %lu not found from the hash table\n",
+                                 block->space,
+                                block->offset);
+                if (buf_page_hash_get(block->space, block->offset)) {
+                        fprintf(stderr,
+"InnoDB: From hash table we find block %lx of %lu %lu which is not %lx\n",
+                (ulint)buf_page_hash_get(block->space, block->offset),
+                        buf_page_hash_get(block->space, block->offset)->space,
+                        buf_page_hash_get(block->space, block->offset)->offset,
+                        (ulint)block);
+                }
+
+                buf_print();
+                buf_LRU_print();
+                buf_validate();
+                buf_LRU_validate();
+
+                ut_a(0);
+        }	
+
 	HASH_DELETE(buf_block_t, hash, buf_pool->page_hash,
 			buf_page_address_fold(block->space, block->offset),
 			block);
@@ -819,7 +856,7 @@ buf_LRU_block_free_hashed_page(
 				be in a state where it can be freed */
 {
 	ut_ad(mutex_own(&(buf_pool->mutex)));
-	ut_ad(block->state == BUF_BLOCK_REMOVE_HASH);
+	ut_a(block->state == BUF_BLOCK_REMOVE_HASH);
 
 	block->state = BUF_BLOCK_MEMORY;
 
diff --git a/innobase/buf/buf0rea.c b/innobase/buf/buf0rea.c
index 8cc379e75d8..0fa6912ba1d 100644
--- a/innobase/buf/buf0rea.c
+++ b/innobase/buf/buf0rea.c
@@ -129,6 +129,8 @@ buf_read_page_low(
 							   offset, sync);
 	}
 
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+
 	*err = fil_io(OS_FILE_READ | wake_later,
 			sync, space,
 			offset, 0, UNIV_PAGE_SIZE,
@@ -604,7 +606,6 @@ buf_read_ibuf_merge_pages(
 	}	
 
 	for (i = 0; i < n_stored; i++) {
-
 		if ((i + 1 == n_stored) && sync) {
 			buf_read_page_low(&err, TRUE, BUF_READ_ANY_PAGE,
 				space_ids[i], space_versions[i], page_nos[i]);
diff --git a/innobase/fil/fil0fil.c b/innobase/fil/fil0fil.c
index 2b0138ccb5a..f96d98c7b2d 100644
--- a/innobase/fil/fil0fil.c
+++ b/innobase/fil/fil0fil.c
@@ -1517,8 +1517,8 @@ try_again:
 	if (space == NULL) {
 		ut_print_timestamp(stderr);
 		fprintf(stderr,
-"  InnoDB: Error: cannot delete tablespace %lu because it is not found\n"
-"InnoDB: in the tablespace memory cache.\n", id);
+"  InnoDB: Error: cannot delete tablespace %lu\n"
+"InnoDB: because it is not found in the tablespace memory cache.\n", id);
 
 		mutex_exit(&(system->mutex));
 	
@@ -2426,19 +2426,24 @@ fil_space_for_table_exists_in_mem(
 		if (namespace == NULL) {
 		        ut_print_timestamp(stderr);
 			fprintf(stderr,
-"  InnoDB: Error: table %s in InnoDB data dictionary has tablespace\n"
-"InnoDB: id %lu, but tablespace with that id or name does not exist. Have\n"
-"InnoDB: you deleted or moved .ibd files? We cannot open table %s now.\n",
-			       name, id, name);
+"  InnoDB: Error: table %s\n"
+"InnoDB: in InnoDB data dictionary has tablespace id %lu,\n"
+"InnoDB: but tablespace with that id or name does not exist. Have\n"
+"InnoDB: you deleted or moved .ibd files?\n",
+			       name, id);
 		} else {
 		        ut_print_timestamp(stderr);
 			fprintf(stderr,
-"  InnoDB: Error: table %s in InnoDB data dictionary has tablespace\n"
-"InnoDB: id %lu, but tablespace with that id does not exist. There is\n"
+"  InnoDB: Error: table %s\n"
+"InnoDB: in InnoDB data dictionary has tablespace id %lu,\n"
+"InnoDB: but tablespace with that id does not exist. There is\n"
 "InnoDB: a tablespace of name %s and id %lu, though. Have\n"
-"InnoDB: you deleted or moved .ibd files? We cannot open table %s now.\n",
-			       name, id, namespace->name, namespace->id, name);
+"InnoDB: you deleted or moved .ibd files?\n",
+			       name, id, namespace->name, namespace->id);
 		}
+		fprintf(stderr,
+"InnoDB: You can look from section 15.1 of http://www.innodb.com/ibman.html\n"
+"InnoDB: how to resolve the issue.\n");
 
 		mutex_exit(&(system->mutex));
 
@@ -2448,16 +2453,20 @@ fil_space_for_table_exists_in_mem(
 	if (0 != strcmp(space->name, path)) {
 		ut_print_timestamp(stderr);
 		fprintf(stderr,
-"  InnoDB: Error: table %s in InnoDB data dictionary has tablespace\n"
-"InnoDB: id %lu, but tablespace with that id has name %s. Have you\n"
-"InnoDB: deleted or moved .ibd files? We cannot open table %s now.\n",
-					name, id, space->name, name);
+"  InnoDB: Error: table %s\n"
+"InnoDB: in InnoDB data dictionary has tablespace id %lu,\n"
+"InnoDB: but tablespace with that id has name %s.\n"
+"InnoDB: Have you deleted or moved .ibd files?", name, id, space->name);
 		if (namespace != NULL) {
 			fprintf(stderr,
-"InnoDB: There is a tablespace with the right name %s, but its id is %lu.\n",
-					namespace->name, namespace->id);
+"InnoDB: There is a tablespace with the right name\n"
+"InnoDB: %s, but its id is %lu.\n", namespace->name, namespace->id);
 		}
 
+		fprintf(stderr,
+"InnoDB: You can look from section 15.1 of http://www.innodb.com/ibman.html\n"
+"InnoDB: how to resolve the issue.\n");
+
 		mutex_exit(&(system->mutex));
 
 		return(FALSE);
diff --git a/innobase/ha/ha0ha.c b/innobase/ha/ha0ha.c
index c7e23d0be1e..87c32bf5dbd 100644
--- a/innobase/ha/ha0ha.c
+++ b/innobase/ha/ha0ha.c
@@ -34,6 +34,12 @@ ha_create(
 
 	table = hash_create(n);
 
+	if (in_btr_search) {
+		table->adaptive = TRUE;
+	} else {
+		table->adaptive = FALSE;
+	}
+
 	if (n_mutexes == 0) {
 		if (in_btr_search) {
 			table->heap = mem_heap_create_in_btr_search(4096);
@@ -106,6 +112,7 @@ ha_insert_for_fold(
 	hash_cell_t*	cell;
 	ha_node_t*	node;
 	ha_node_t*	prev_node;
+	buf_block_t*	prev_block;
 	ulint		hash;
 
 	ut_ad(table && data);
@@ -119,6 +126,12 @@ ha_insert_for_fold(
 
 	while (prev_node != NULL) {
 		if (prev_node->fold == fold) {
+			if (table->adaptive) {
+				prev_block = buf_block_align(prev_node->data);
+				ut_a(prev_block->n_pointers > 0);
+				prev_block->n_pointers--;
+				buf_block_align(data)->n_pointers++;
+			}
 
 			prev_node->data = data;
 
@@ -142,6 +155,11 @@ ha_insert_for_fold(
 	}
 	
 	ha_node_set_data(node, data);
+
+	if (table->adaptive) {
+		buf_block_align(data)->n_pointers++;
+	}
+
 	node->fold = fold;
 
 	node->next = NULL;
@@ -174,6 +192,11 @@ ha_delete_hash_node(
 	hash_table_t*	table,		/* in: hash table */
 	ha_node_t*	del_node)	/* in: node to be deleted */
 {
+	if (table->adaptive) {
+		ut_a(buf_block_align(del_node->data)->n_pointers > 0);
+		buf_block_align(del_node->data)->n_pointers--;
+	}
+
 	HASH_DELETE_AND_COMPACT(ha_node_t, next, table, del_node);
 }
 
@@ -199,6 +222,35 @@ ha_delete(
 	ha_delete_hash_node(table, node);
 }	
 
+/*************************************************************
+Looks for an element when we know the pointer to the data, and updates
+the pointer to data, if found. */
+
+void
+ha_search_and_update_if_found(
+/*==========================*/
+	hash_table_t*	table,	/* in: hash table */
+	ulint		fold,	/* in: folded value of the searched data */
+	void*		data,	/* in: pointer to the data */
+	void*		new_data)/* in: new pointer to the data */
+{
+	ha_node_t*	node;
+
+	ut_ad(!table->mutexes || mutex_own(hash_get_mutex(table, fold)));
+
+	node = ha_search_with_data(table, fold, data);
+
+	if (node) {
+		if (table->adaptive) {
+			ut_a(buf_block_align(node->data)->n_pointers > 0);
+			buf_block_align(node->data)->n_pointers--;
+			buf_block_align(new_data)->n_pointers++;
+		}
+
+		node->data = new_data;
+	}
+}
+
 /*********************************************************************
 Removes from the chain determined by fold all nodes whose data pointer
 points to the page given. */
@@ -229,10 +281,10 @@ ha_remove_all_nodes_to_page(
 
 			node = ha_chain_get_first(table, fold);
 		} else {
-			node = ha_chain_get_next(table, node);
+			node = ha_chain_get_next(node);
 		}
 	}
-
+#ifdef UNIV_DEBUG
 	/* Check that all nodes really got deleted */
 	
 	node = ha_chain_get_first(table, fold);
@@ -240,8 +292,9 @@ ha_remove_all_nodes_to_page(
 	while (node) {
 		ut_a(buf_frame_align(ha_node_get_data(node)) != page);
 
-		node = ha_chain_get_next(table, node);
+		node = ha_chain_get_next(node);
 	}
+#endif
 }
 
 /*****************************************************************
@@ -293,12 +346,10 @@ ha_print_info(
 	hash_table_t*	table)	/* in: hash table */
 {
 	hash_cell_t*	cell;
-/*
-        ha_node_t*      node;
-        ulint           len     = 0;
-        ulint           max_len = 0;
-        ulint           nodes   = 0;
-*/
+/*	ha_node_t*	node;
+	ulint		nodes	= 0;
+	ulint		len	= 0;
+	ulint		max_len	= 0; */
 	ulint		cells	= 0;
 	ulint		n_bufs;
 	ulint		i;
diff --git a/innobase/ha/hash0hash.c b/innobase/ha/hash0hash.c
index 1f7edf9d7d2..facdea66198 100644
--- a/innobase/ha/hash0hash.c
+++ b/innobase/ha/hash0hash.c
@@ -91,6 +91,7 @@ hash_create(
 
 	array = ut_malloc(sizeof(hash_cell_t) * prime);
 	
+	table->adaptive = FALSE;
 	table->array = array;
 	table->n_cells = prime;
 	table->n_mutexes = 0;
diff --git a/innobase/include/buf0buf.h b/innobase/include/buf0buf.h
index 0457da60534..3f2fd5bbbe0 100644
--- a/innobase/include/buf0buf.h
+++ b/innobase/include/buf0buf.h
@@ -755,12 +755,16 @@ struct buf_block_struct{
 
 	UT_LIST_NODE_T(buf_block_t) free;
 					/* node of the free block list */
+	ibool		in_free_list;	/* TRUE if in the free list; used in
+					debugging */
 	UT_LIST_NODE_T(buf_block_t) LRU;
 					/* node of the LRU list */
 	UT_LIST_NODE_T(buf_block_t) awe_LRU_free_mapped;
 					/* in the AWE version node in the
 					list of free and LRU blocks which are
 					mapped to a frame */
+	ibool		in_LRU_list;	/* TRUE of the page is in the LRU list;
+					used in debugging */
 	ulint		LRU_position;	/* value which monotonically
 					decreases (or may stay constant if
 					the block is in the old blocks) toward
@@ -821,6 +825,9 @@ struct buf_block_struct{
 					complete, though: there may have been
 					hash collisions, record deletions,
 					etc. */
+	ulint		n_pointers;	/* used in debugging: the number of
+					pointers in the adaptive hash index
+					pointing to this frame */
 	ulint		curr_n_fields;	/* prefix length for hash indexing:
 					number of full fields */
 	ulint		curr_n_bytes;	/* number of bytes in hash indexing */
diff --git a/innobase/include/buf0buf.ic b/innobase/include/buf0buf.ic
index d4e7122f3f9..281bb1ea527 100644
--- a/innobase/include/buf0buf.ic
+++ b/innobase/include/buf0buf.ic
@@ -28,7 +28,6 @@ buf_block_peek_if_too_old(
 {
 	if (buf_pool->freed_page_clock >= block->freed_page_clock 
 				+ 1 + (buf_pool->curr_size / 1024)) {
-		
 		return(TRUE);
 	}
 
@@ -169,7 +168,7 @@ buf_block_get_space(
 	ut_ad(block);
 	ut_ad(block >= buf_pool->blocks);
 	ut_ad(block < buf_pool->blocks + buf_pool->max_size);
-	ut_ad(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
 	ut_ad(block->buf_fix_count > 0);
 	
 	return(block->space);
@@ -187,7 +186,7 @@ buf_block_get_page_no(
 	ut_ad(block);
 	ut_ad(block >= buf_pool->blocks);
 	ut_ad(block < buf_pool->blocks + buf_pool->max_size);
-	ut_ad(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
 	ut_ad(block->buf_fix_count > 0);
 	
 	return(block->offset);
@@ -550,6 +549,8 @@ buf_page_hash_get(
 
 	HASH_SEARCH(hash, buf_pool->page_hash, fold, block,
 			(block->space == space) && (block->offset == offset));
+	ut_a(block == NULL || block->state == BUF_BLOCK_FILE_PAGE);
+	
 	return(block);
 }
 
@@ -617,8 +618,8 @@ buf_page_release(
 
 	mutex_enter_fast(&(buf_pool->mutex));
 
-	ut_ad(block->state == BUF_BLOCK_FILE_PAGE);
-	ut_ad(block->buf_fix_count > 0);
+	ut_a(block->state == BUF_BLOCK_FILE_PAGE);
+	ut_a(block->buf_fix_count > 0);
 
 	if (rw_latch == RW_X_LATCH && mtr->modifications) {
 
diff --git a/innobase/include/ha0ha.h b/innobase/include/ha0ha.h
index 0beac928b7e..c3fc04b47bb 100644
--- a/innobase/include/ha0ha.h
+++ b/innobase/include/ha0ha.h
@@ -28,7 +28,7 @@ ha_search_and_get_data(
 /*************************************************************
 Looks for an element when we know the pointer to the data and updates
 the pointer to data if found. */
-UNIV_INLINE
+
 void
 ha_search_and_update_if_found(
 /*==========================*/
diff --git a/innobase/include/ha0ha.ic b/innobase/include/ha0ha.ic
index 761bc3b20de..22da7107659 100644
--- a/innobase/include/ha0ha.ic
+++ b/innobase/include/ha0ha.ic
@@ -49,7 +49,6 @@ ha_node_t*
 ha_chain_get_next(
 /*==============*/
 				/* out: next node, NULL if none */
-	hash_table_t*	table __attribute__((unused)),	/* in: hash table */
 	ha_node_t*	node)	/* in: hash chain node */
 {
 	ut_ad(table);
@@ -94,7 +93,7 @@ ha_search(
 			return(node);
 		}
 
-		node = ha_chain_get_next(table, node);
+		node = ha_chain_get_next(node);
 	}
 
 	return(NULL);
@@ -124,7 +123,7 @@ ha_search_and_get_data(
 			return(node->data);
 		}
 
-		node = ha_chain_get_next(table, node);
+		node = ha_chain_get_next(node);
 	}
 
 	return(NULL);
@@ -139,7 +138,6 @@ ha_next(
 				/* out: pointer to the next hash table node
 				in chain with the fold value, NULL if not
 				found */
-	hash_table_t*	table,	/* in: hash table */
 	ha_node_t*	node)	/* in: hash table node */
 {
 	ulint	fold;
@@ -148,7 +146,7 @@ ha_next(
 
 	ut_ad(!table->mutexes || mutex_own(hash_get_mutex(table, fold)));
 
-	node = ha_chain_get_next(table, node);
+	node = ha_chain_get_next(node);
 
 	while (node) {
 		if (node->fold == fold) {
@@ -156,7 +154,7 @@ ha_next(
 			return(node);
 		}
 
-		node = ha_chain_get_next(table, node);
+		node = ha_chain_get_next(node);
 	}
 
 	return(NULL);
@@ -186,36 +184,13 @@ ha_search_with_data(
 			return(node);
 		}
 
-		node = ha_chain_get_next(table, node);
+		node = ha_chain_get_next(node);
 	}
 
 	return(NULL);
 }
 
 /*************************************************************
-Looks for an element when we know the pointer to the data, and updates
-the pointer to data, if found. */
-UNIV_INLINE
-void
-ha_search_and_update_if_found(
-/*==========================*/
-	hash_table_t*	table,	/* in: hash table */
-	ulint		fold,	/* in: folded value of the searched data */
-	void*		data,	/* in: pointer to the data */
-	void*		new_data)/* in: new pointer to the data */
-{
-	ha_node_t*	node;
-
-	ut_ad(!table->mutexes || mutex_own(hash_get_mutex(table, fold)));
-
-	node = ha_search_with_data(table, fold, data);
-
-	if (node) {
-		node->data = new_data;
-	}
-}
-
-/*************************************************************
 Looks for an element when we know the pointer to the data, and deletes
 it from the hash table, if found. */
 UNIV_INLINE
diff --git a/innobase/include/hash0hash.h b/innobase/include/hash0hash.h
index 378925a5bea..2e9ab498116 100644
--- a/innobase/include/hash0hash.h
+++ b/innobase/include/hash0hash.h
@@ -100,7 +100,7 @@ Deletes a struct from a hash table. */
 \
 		while (struct3333->NAME != DATA) {\
 \
-			ut_ad(struct3333)\
+			ut_a(struct3333)\
 			struct3333 = struct3333->NAME;\
 		}\
 \
@@ -322,6 +322,8 @@ struct hash_cell_struct{
 
 /* The hash table structure */
 struct hash_table_struct {
+	ibool		adaptive;/* TRUE if this is the hash table of the
+				adaptive hash index */
 	ulint		n_cells;/* number of cells in the hash table */
 	hash_cell_t*	array;	/* pointer to cell array */
 	ulint		n_mutexes;/* if mutexes != NULL, then the number of
diff --git a/innobase/include/ibuf0ibuf.ic b/innobase/include/ibuf0ibuf.ic
index 0886c8c02cc..68f7ce9c1d0 100644
--- a/innobase/include/ibuf0ibuf.ic
+++ b/innobase/include/ibuf0ibuf.ic
@@ -218,7 +218,7 @@ ibuf_update_free_bits_if_full(
 	}
 
 	if (after == 0) {
-		/* We move the page to front of the buffer pool LRU list:
+		/* We move the page to the front of the buffer pool LRU list:
 		the purpose of this is to prevent those pages to which we
 		cannot make inserts using the insert buffer from slipping
 		out of the buffer pool */
diff --git a/innobase/include/row0mysql.h b/innobase/include/row0mysql.h
index 1964f53dabb..fade3709631 100644
--- a/innobase/include/row0mysql.h
+++ b/innobase/include/row0mysql.h
@@ -339,6 +339,45 @@ row_drop_table_for_mysql(
 	char*	name,	/* in: table name */
 	trx_t*	trx);	/* in: transaction handle */
 /*************************************************************************
+Discards the tablespace of a table which stored in an .ibd file. Discarding
+means that this function deletes the .ibd file and assigns a new table id for
+the table. Also the flag table->ibd_file_missing is set TRUE.
+
+How do we prevent crashes caused by ongoing operations on the table? Old
+operations could try to access non-existent pages.
+
+1) SQL queries, INSERT, SELECT, ...: we must get an exclusive MySQL table lock
+on the table before we can do DISCARD TABLESPACE. Then there are no running
+queries on the table.
+2) Purge and rollback: we assign a new table id for the table. Since purge and
+rollback look for the table based on the table id, they see the table as
+'dropped' and discard their operations.
+3) Insert buffer: we remove all entries for the tablespace in the insert
+buffer tree; as long as the tablespace mem object does not exist, ongoing
+insert buffer page merges are discarded in buf0rea.c. If we recreate the
+tablespace mem object with IMPORT TABLESPACE later, then the tablespace will
+have the same id, but the tablespace_version field in the mem object is
+different, and ongoing old insert buffer page merges get discarded.
+4) Linear readahead and random readahead: we use the same method as in 3) to
+discard ongoing operations. */
+
+int
+row_discard_tablespace_for_mysql(
+/*=============================*/
+			/* out: error code or DB_SUCCESS */
+	char*	name,	/* in: table name */
+	trx_t*	trx);	/* in: transaction handle */
+/*********************************************************************
+Imports a tablespace. The space id in the .ibd file must match the space id
+of the table in the data dictionary. */
+
+int
+row_import_tablespace_for_mysql(
+/*============================*/
+			/* out: error code or DB_SUCCESS */
+	char*	name,	/* in: table name */
+	trx_t*	trx);	/* in: transaction handle */
+/*************************************************************************
 Drops a database for MySQL. */
 
 int
diff --git a/innobase/page/page0page.c b/innobase/page/page0page.c
index e087941a970..2422f0ff87e 100644
--- a/innobase/page/page0page.c
+++ b/innobase/page/page0page.c
@@ -582,7 +582,8 @@ byte*
 page_parse_delete_rec_list(
 /*=======================*/
 			/* out: end of log record or NULL */
-	byte	type,	/* in: MLOG_LIST_END_DELETE or MLOG_LIST_START_DELETE */
+	byte	type,	/* in: MLOG_LIST_END_DELETE or
+			MLOG_LIST_START_DELETE */
 	byte*	ptr,	/* in: buffer */
 	byte*	end_ptr,/* in: buffer end */
 	page_t*	page,	/* in: page or NULL */	
diff --git a/innobase/row/row0mysql.c b/innobase/row/row0mysql.c
index 497b74fd320..5d5985d16af 100644
--- a/innobase/row/row0mysql.c
+++ b/innobase/row/row0mysql.c
@@ -2007,9 +2007,6 @@ row_import_tablespace_for_mysql(
 
 	success = fil_open_single_table_tablespace(table->space, table->name);
 
-	printf(
-"Remember to stop purge + undo if table->ibd_file_is_missing!!!\n");
-
 	if (success) {
 		table->ibd_file_missing = FALSE;
 		table->tablespace_discarded = FALSE;
diff --git a/innobase/row/row0purge.c b/innobase/row/row0purge.c
index 104d71eda2d..99332dc275d 100644
--- a/innobase/row/row0purge.c
+++ b/innobase/row/row0purge.c
@@ -529,6 +529,14 @@ row_purge_parse_undo_rec(
 		return(FALSE);
 	}
 
+	if (node->table->ibd_file_missing) {
+		/* We skip purge of missing .ibd files */
+
+		node->table = NULL;
+
+		return;
+	}
+
 	clust_index = dict_table_get_first_index(node->table);
 
 	if (clust_index == NULL) {
diff --git a/innobase/row/row0uins.c b/innobase/row/row0uins.c
index fff67dcd627..08f0e29c839 100644
--- a/innobase/row/row0uins.c
+++ b/innobase/row/row0uins.c
@@ -258,6 +258,13 @@ row_undo_ins_parse_undo_rec(
 		return;
 	}
 
+	if (node->table->ibd_file_missing) {
+		/* We skip undo operations to missing .ibd files */
+		node->table = NULL;
+
+		return;
+	}
+
 	clust_index = dict_table_get_first_index(node->table);
 	
 	ptr = trx_undo_rec_get_row_ref(ptr, clust_index, &(node->ref),
diff --git a/innobase/row/row0umod.c b/innobase/row/row0umod.c
index b22e494f891..0a050e0a1b6 100644
--- a/innobase/row/row0umod.c
+++ b/innobase/row/row0umod.c
@@ -620,6 +620,13 @@ row_undo_mod_parse_undo_rec(
 	        return;
 	}
 
+	if (node->table->ibd_file_missing) {
+		/* We skip undo operations to missing .ibd files */
+		node->table = NULL;
+
+		return;
+	}
+
 	clust_index = dict_table_get_first_index(node->table);
 
 	ptr = trx_undo_update_rec_get_sys_cols(ptr, &trx_id, &roll_ptr,
diff --git a/sql/ha_innodb.cc b/sql/ha_innodb.cc
index f1072c3137a..d07b166d9e2 100644
--- a/sql/ha_innodb.cc
+++ b/sql/ha_innodb.cc
@@ -1451,7 +1451,7 @@ ha_innobase::open(
     		DBUG_RETURN(1);
   	}
 
- 	if (ib_table->ibd_file_missing) {
+ 	if (ib_table->ibd_file_missing && !current_thd->tablespace_op) {
 	        ut_print_timestamp(stderr);
 	        fprintf(stderr, "  InnoDB error:\n"
 "MySQL is trying to open a table handle but the .ibd file for\n"
@@ -3629,6 +3629,42 @@ ha_innobase::create(
 }
 
 /*********************************************************************
+Discards or imports an InnoDB tablespace. */
+
+int
+ha_innobase::discard_or_import_tablespace(
+/*======================================*/
+				/* out: 0 == success, -1 == error */
+	my_bool discard)	/* in: TRUE if discard, else import */
+{
+	row_prebuilt_t* prebuilt	= (row_prebuilt_t*) innobase_prebuilt;
+	dict_table_t*	table;
+	trx_t*		trx;
+	int		err;
+
+ 	DBUG_ENTER("ha_innobase::discard_or_import_tablespace");
+
+	ut_a(prebuilt->trx && prebuilt->trx->magic_n == TRX_MAGIC_N);
+	ut_a(prebuilt->trx ==
+		(trx_t*) current_thd->transaction.all.innobase_tid);
+
+	table = prebuilt->table;
+	trx = prebuilt->trx;
+
+	if (discard) {
+		err = row_discard_tablespace_for_mysql(table->name, trx);
+	} else {
+		err = row_import_tablespace_for_mysql(table->name, trx);
+	}
+
+	if (err == DB_SUCCESS) {
+		DBUG_RETURN(0);
+	}
+
+	DBUG_RETURN(-1);
+}
+
+/*********************************************************************
 Drops a table from an InnoDB database. Before calling this function,
 MySQL calls innobase_commit to commit the transaction of the current user.
 Then the current user cannot have locks set on the table. Drop table
@@ -3647,7 +3683,7 @@ ha_innobase::delete_table(
 	trx_t*	trx;
 	char	norm_name[1000];
 
-  	DBUG_ENTER("ha_innobase::delete_table");
+ 	DBUG_ENTER("ha_innobase::delete_table");
 
 	/* Get the transaction associated with the current thd, or create one
 	if not yet created */
@@ -4536,7 +4572,8 @@ ha_innobase::external_lock(
 
 	update_thd(thd);
 
- 	if (lock_type != F_UNLCK && prebuilt->table->ibd_file_missing) {
+ 	if (lock_type != F_UNLCK && prebuilt->table->ibd_file_missing
+	    && !current_thd->tablespace_op) {
 	        ut_print_timestamp(stderr);
 	        fprintf(stderr, "  InnoDB error:\n"
 "MySQL is trying to use a table handle but the .ibd file for\n"
@@ -4546,6 +4583,7 @@ ha_innobase::external_lock(
 "Look from section 15.1 of http://www.innodb.com/ibman.html\n"
 "how you can resolve the problem.\n",
 				prebuilt->table->name);
+		DBUG_RETURN(HA_ERR_CRASHED);
 	}
 
 	trx = prebuilt->trx;
@@ -4793,11 +4831,12 @@ ha_innobase::store_lock(
 
 	if (lock_type != TL_IGNORE && lock.type == TL_UNLOCK) {
 
-    		/* If we are not doing a LOCK TABLE, then allow multiple
-		writers */
+    		/* If we are not doing a LOCK TABLE or DISCARD/IMPORT
+		TABLESPACE, then allow multiple writers */
 
     		if ((lock_type >= TL_WRITE_CONCURRENT_INSERT &&
-	 	    lock_type <= TL_WRITE) && !thd->in_lock_tables) {
+	 	    lock_type <= TL_WRITE) && !thd->in_lock_tables
+		    && !thd->tablespace_op) {
 
       			lock_type = TL_WRITE_ALLOW_WRITE;
       		}
diff --git a/sql/ha_innodb.h b/sql/ha_innodb.h
index b17097b3c57..0c89a9d29ce 100644
--- a/sql/ha_innodb.h
+++ b/sql/ha_innodb.h
@@ -160,6 +160,7 @@ class ha_innobase: public handler
   	void info(uint);
         int analyze(THD* thd,HA_CHECK_OPT* check_opt);
         int optimize(THD* thd,HA_CHECK_OPT* check_opt);
+	int discard_or_import_tablespace(my_bool discard);
   	int extra(enum ha_extra_function operation);
   	int reset(void);
   	int external_lock(THD *thd, int lock_type);
diff --git a/sql/handler.h b/sql/handler.h
index b74e06c6edf..b756d9a09fb 100644
--- a/sql/handler.h
+++ b/sql/handler.h
@@ -317,6 +317,7 @@ public:
   virtual int dump(THD* thd, int fd = -1) { return ER_DUMP_NOT_IMPLEMENTED; }
   virtual void deactivate_non_unique_index(ha_rows rows) {}
   virtual bool activate_all_index(THD *thd) {return 0;}
+  virtual int discard_or_import_tablespace(my_bool discard) {return -1;}
   // not implemented by default
   virtual int net_read_dump(NET* net)
   { return ER_DUMP_NOT_IMPLEMENTED; }
diff --git a/sql/lex.h b/sql/lex.h
index e11b50ed16d..859f92dd752 100644
--- a/sql/lex.h
+++ b/sql/lex.h
@@ -130,6 +130,7 @@ static SYMBOL symbols[] = {
   { "DESCRIBE",		SYM(DESCRIBE),0,0},
   { "DIRECTORY",	SYM(DIRECTORY_SYM),0,0},
   { "DISABLE",		SYM(DISABLE_SYM),0,0},
+  { "DISCARD",		SYM(DISCARD),0,0},
   { "DISTINCT",		SYM(DISTINCT),0,0},
   { "DISTINCTROW",	SYM(DISTINCT),0,0},	/* Access likes this */
   { "DIV",		SYM(DIV_SYM),0,0},
@@ -200,6 +201,7 @@ static SYMBOL symbols[] = {
   { "INNER",		SYM(INNER_SYM),0,0},
   { "INNOBASE",		SYM(INNOBASE_SYM),0,0},
   { "INNODB",		SYM(INNOBASE_SYM),0,0},
+  { "IMPORT",		SYM(IMPORT),0,0},
   { "INSERT",		SYM(INSERT),0,0},
   { "INSERT_METHOD",    SYM(INSERT_METHOD),0,0},
   { "INT",		SYM(INT_SYM),0,0},
@@ -387,6 +389,7 @@ static SYMBOL symbols[] = {
   { "SUPER",		SYM(SUPER_SYM),0,0},
   { "TABLE",		SYM(TABLE_SYM),0,0},
   { "TABLES",		SYM(TABLES),0,0},
+  { "TABLESPACE",	SYM(TABLESPACE),0,0},
   { "TEMPORARY",	SYM(TEMPORARY),0,0},
   { "TERMINATED",	SYM(TERMINATED),0,0},
   { "TEXT",		SYM(TEXT_SYM),0,0},
diff --git a/sql/mysql_priv.h b/sql/mysql_priv.h
index afbda2b4ad1..a1919bf1a0e 100644
--- a/sql/mysql_priv.h
+++ b/sql/mysql_priv.h
@@ -486,6 +486,7 @@ int mysql_alter_table(THD *thd, char *new_db, char *new_name,
 		      bool drop_primary,
 		      enum enum_duplicates handle_duplicates,
 		      enum enum_enable_or_disable keys_onoff=LEAVE_AS_IS,
+		      enum tablespace_op_type tablespace_op=NO_TABLESPACE_OP,
 		      bool simple_alter=0);
 int mysql_create_like_table(THD *thd, TABLE_LIST *table,
                             HA_CREATE_INFO *create_info,
diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index cdca7454698..c7d77c67236 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -173,6 +173,7 @@ THD::THD():user_time(0), is_fatal_error(0),
   protocol_simple.init(this);
   protocol_prep.init(this);
 
+  tablespace_op=FALSE;
 #ifdef USING_TRANSACTIONS
   bzero((char*) &transaction,sizeof(transaction));
   if (opt_using_transactions)
diff --git a/sql/sql_class.h b/sql/sql_class.h
index 5e5d0335e9d..146ee18e3e2 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -502,6 +502,7 @@ public:
   time_t     connect_time,thr_create_time; // track down slow pthread_create
   thr_lock_type update_lock_default;
   delayed_insert *di;
+  my_bool    tablespace_op;	/* This is TRUE in DISCARD/IMPORT TABLESPACE */
   struct st_transactions {
     IO_CACHE trans_log;
     THD_TRANS all;			// Trans since BEGIN WORK
diff --git a/sql/sql_lex.h b/sql/sql_lex.h
index 8ce028020c2..0166951ab9d 100644
--- a/sql/sql_lex.h
+++ b/sql/sql_lex.h
@@ -110,6 +110,11 @@ enum olap_type
   UNSPECIFIED_OLAP_TYPE, CUBE_TYPE, ROLLUP_TYPE
 };
 
+enum tablespace_op_type
+{
+  NO_TABLESPACE_OP, DISCARD_TABLESPACE, IMPORT_TABLESPACE
+};
+
 /* 
   The state of the lex parsing for selects 
    
@@ -530,6 +535,7 @@ typedef struct st_lex
   enum ha_rkey_function ha_rkey_mode;
   enum enum_enable_or_disable alter_keys_onoff;
   enum enum_var_type option_type;
+  enum tablespace_op_type tablespace_op;
   uint uint_geom_type;
   uint grant, grant_tot_col, which_columns;
   uint fk_delete_opt, fk_update_opt, fk_match_option;
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index e30fd0acfae..248dfc0e47a 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -2207,7 +2207,9 @@ mysql_execute_command(THD *thd)
 			       select_lex->order_list.elements,
                                (ORDER *) select_lex->order_list.first,
 			       lex->drop_primary, lex->duplicates,
-			       lex->alter_keys_onoff, lex->simple_alter);
+			       lex->alter_keys_onoff,
+                               lex->tablespace_op,
+			       lex->simple_alter);
       }
       break;
     }
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index 16afd592e59..3840e29f04a 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -1748,6 +1748,70 @@ int mysql_check_table(THD* thd, TABLE_LIST* tables,HA_CHECK_OPT* check_opt)
 				&handler::check));
 }
 
+/* table_list should contain just one table */
+int mysql_discard_or_import_tablespace(THD *thd,
+		      TABLE_LIST *table_list,
+		      enum tablespace_op_type tablespace_op)
+{
+  TABLE *table;
+  my_bool discard;
+  int error;
+  DBUG_ENTER("mysql_discard_or_import_tablespace");
+
+  /* Note that DISCARD/IMPORT TABLESPACE always is the only operation in an
+  ALTER TABLE */
+
+  thd->proc_info="discard_or_import_tablespace";
+
+  if (tablespace_op == DISCARD_TABLESPACE)
+    discard = TRUE;
+  else
+    discard = FALSE;
+
+  thd->tablespace_op=TRUE; /* we set this flag so that ha_innobase::open
+			   and ::external_lock() do not complain when we
+			   lock the table */
+  mysql_ha_closeall(thd, table_list);
+
+  if (!(table=open_ltable(thd,table_list,TL_WRITE)))
+  {
+    thd->tablespace_op=FALSE;
+    DBUG_RETURN(-1);
+  }
+  
+  thd->tablespace_op=FALSE;
+
+  error=table->file->discard_or_import_tablespace(discard);
+
+  thd->proc_info="end";
+
+  if (error)
+    goto err;
+
+  /* The 0 in the call below means 'not in a transaction', which means
+  immediate invalidation; that is probably what we wish here */
+  query_cache_invalidate3(thd, table_list, 0);
+
+  /* The ALTER TABLE is always in its own transaction */
+  error = ha_commit_stmt(thd);
+  if (ha_commit(thd))
+    error=1;
+  if (error)
+    goto err;
+  mysql_update_log.write(thd, thd->query,thd->query_length);
+  if (mysql_bin_log.is_open())
+  {
+    Query_log_event qinfo(thd, thd->query, thd->query_length, 0);
+    mysql_bin_log.write(&qinfo);
+  }
+err:
+  close_thread_tables(thd);
+  if (error == 0) {
+    send_ok(thd);
+   DBUG_RETURN(0);
+  }
+  DBUG_RETURN(error);
+}
 
 int mysql_alter_table(THD *thd,char *new_db, char *new_name,
 		      HA_CREATE_INFO *create_info,
@@ -1759,6 +1823,7 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
 		      bool drop_primary,
 		      enum enum_duplicates handle_duplicates,
 	              enum enum_enable_or_disable keys_onoff,
+		      enum tablespace_op_type tablespace_op,
                       bool simple_alter)
 {
   TABLE *table,*new_table;
@@ -1771,6 +1836,7 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
   ulonglong next_insert_id;
   uint save_time_stamp,db_create_options, used_fields;
   enum db_type old_db_type,new_db_type;
+  thr_lock_type lock_type;
   DBUG_ENTER("mysql_alter_table");
 
   thd->proc_info="init";
@@ -1781,6 +1847,10 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
   used_fields=create_info->used_fields;
 
   mysql_ha_closeall(thd, table_list);
+
+  if (tablespace_op != NO_TABLESPACE_OP)
+    DBUG_RETURN(mysql_discard_or_import_tablespace(thd,table_list,
+							tablespace_op));
   if (!(table=open_ltable(thd,table_list,TL_WRITE_ALLOW_READ)))
     DBUG_RETURN(-1);
 
@@ -1834,8 +1904,6 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
   if (create_info->row_type == ROW_TYPE_NOT_USED)
     create_info->row_type=table->row_type;
 
-  /* In some simple cases we need not to recreate the table */
-
   thd->proc_info="setup";
   if (simple_alter && !table->tmp_table)
   {
@@ -1860,6 +1928,7 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
       }
       VOID(pthread_mutex_unlock(&LOCK_open));
     }
+
     if (!error)
     {
       switch (keys_onoff) {
@@ -2395,8 +2464,7 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
       goto err;
     }
   }
-
-  /* The ALTER TABLE is always in it's own transaction */
+  /* The ALTER TABLE is always in its own transaction */
   error = ha_commit_stmt(thd);
   if (ha_commit(thd))
     error=1;
@@ -2695,4 +2763,3 @@ int mysql_checksum_table(THD *thd, TABLE_LIST *tables, HA_CHECK_OPT *check_opt)
     table->table=0;
   DBUG_RETURN(-1);
 }
-
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 81a59196e3c..f917e4ec027 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -211,6 +211,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	DESCRIBE
 %token	DES_KEY_FILE
 %token	DISABLE_SYM
+%token	DISCARD
 %token	DISTINCT
 %token  DUPLICATE_SYM
 %token	DYNAMIC_SYM
@@ -244,6 +245,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	HOSTS_SYM
 %token	IDENT
 %token	IGNORE_SYM
+%token	IMPORT
 %token	INDEX
 %token	INDEXES
 %token	INFILE
@@ -360,6 +362,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	SUBJECT_SYM
 %token	TABLES
 %token	TABLE_SYM
+%token	TABLESPACE
 %token	TEMPORARY
 %token	TERMINATED
 %token	TEXT_STRING
@@ -1635,6 +1638,7 @@ alter:
 	  lex->create_info.table_charset= thd->variables.collation_database;
 	  lex->create_info.row_type= ROW_TYPE_NOT_USED;
           lex->alter_keys_onoff=LEAVE_AS_IS;
+	  lex->tablespace_op=NO_TABLESPACE_OP;
           lex->simple_alter=1;
 	}
 	alter_list
@@ -1648,6 +1652,8 @@ alter:
 
 
 alter_list:
+	| DISCARD TABLESPACE { Lex->tablespace_op=DISCARD_TABLESPACE; }
+	| IMPORT TABLESPACE { Lex->tablespace_op=IMPORT_TABLESPACE; }
         | alter_list_item
 	| alter_list ',' alter_list_item;