Moved uplink mutex / condition init and destroy to task creation and destruction functions. Finally, some small code refactoring.

2 files changed, 62 insertions, 37 deletions

diff --git a/src/server/iscsi.c b/src/server/iscsi.c
index c634013..afb1e6c 100644
--- a/src/server/iscsi.c
+++ b/src/server/iscsi.c
@@ -1312,7 +1312,7 @@ int iscsi_create()
 		}
 
 		globvec->flags                          = (ISCSI_GLOBALS_FLAGS_INIT_R2T | ISCSI_GLOBALS_FLAGS_IMMEDIATE_DATA | ISCSI_GLOBALS_FLAGS_DATA_PDU_IN_ORDER | ISCSI_GLOBALS_FLAGS_DATA_SEQ_IN_ORDER | ISCSI_GLOBALS_FLAGS_SCSI_IO_REMOVABLE | ISCSI_GLOBALS_FLAGS_SCSI_IO_WRITE_PROTECT);
-		globvec->target_name_check              = ISCSI_GLOBALS_TARGET_NAME_CHECK_RELAXED;
+		globvec->target_name_check              = ISCSI_GLOBALS_TARGET_NAME_CHECK_FULL;
 		globvec->max_sessions                   = 0U;
 		globvec->header_digest                  = 0;
 		globvec->data_digest                    = 0;
@@ -2871,6 +2871,20 @@ iscsi_task *iscsi_task_create(iscsi_connection *conn, iscsi_task *parent, iscsi_
 
 	iscsi_scsi_task_create( &task->scsi_task, callback, iscsi_task_destroy_callback );
 
+	if ( pthread_mutex_init( &task->scsi_task.uplink_mutex, NULL ) != 0 ) {
+		logadd( LOG_ERROR, "iscsi_task_create: Error while initializing DNBD3 uplink mutex for iSCSI SCSI task" );
+
+		return NULL;
+	}
+
+	if ( pthread_cond_init( &task->scsi_task.uplink_cond, NULL ) != 0 ) {
+		logadd( LOG_ERROR, "iscsi_task_create: Error while initializing DNBD3 uplink condition for iSCSI SCSI task" );
+
+		pthread_mutex_destroy( &task->scsi_task.uplink_mutex );
+
+		return NULL;
+	}
+
 	if ( parent != NULL ) {
 		parent->scsi_task.ref++;
 
@@ -2917,6 +2931,9 @@ void iscsi_task_destroy_callback(iscsi_scsi_task *scsi_task)
 			task->parent = NULL;
 		}
 
+		pthread_cond_destroy( &task->scsi_task.uplink_cond );
+		pthread_mutex_destroy( &task->scsi_task.uplink_mutex );
+
 		if ( task->pdu != NULL ) {
 			iscsi_connection_pdu_destroy( task->pdu );
 
@@ -3852,13 +3869,13 @@ void iscsi_scsi_task_create(iscsi_scsi_task *scsi_task, iscsi_scsi_task_xfer_com
 	scsi_task->target_port            = NULL;
 	scsi_task->init_port              = NULL;
 	scsi_task->cdb                    = NULL;
+	scsi_task->sense_data             = NULL;
 	scsi_task->xfer_complete_callback = xfer_complete_callback;
 	scsi_task->destroy_callback       = destroy_callback;
 	scsi_task->io_complete_callback   = NULL;
 	scsi_task->io_wait.image          = NULL;
 	scsi_task->io_wait.callback       = NULL;
 	scsi_task->io_wait.user_data      = NULL;
-	scsi_task->sense_data             = NULL;
 	scsi_task->buf                    = NULL;
 	scsi_task->pos                    = 0UL;
 	scsi_task->len                    = 0UL;
@@ -5273,20 +5290,28 @@ static uint64_t iscsi_scsi_emu_blocks_to_bytes(uint64_t *offset_bytes, const uin
 /**
  * @brief Called when data requested via an uplink server has arrived.
  *
- * @param[in] data related scsi_task
- * @param[in] handle pointer to destination buffer, as passed to iscsi_scsi_emu_io_block_read()
- * @param[in] start start of range in bytes
- * @param[in] length length of range in bytes, as passed to uplink_request()
- * @param[in] buffer data for requested range
+ * This function is used to retrieve
+ * block data which is NOT locally
+ * available.
+ *
+ * @param[in] data Pointer to related scsi_task. May NOT
+ * be NULL, so be careful.
+ * @param[in] handle Pointer to destination buffer, as passed to
+ * iscsi_scsi_emu_io_block_read().
+ * @param[in] start Start of range in bytes.
+ * @param[in] length Length of range in bytes, as passed to
+ * uplink_request().
+ * @param[in] buffer Data for requested range.
  */
 static void iscsi_uplink_callback(void *data, uint64_t handle, uint64_t start UNUSED, uint32_t length, const char *buffer)
 {
-	iscsi_scsi_task *scsi_task = (iscsi_scsi_task*)data;
+	iscsi_scsi_task *scsi_task = (iscsi_scsi_task *) data;
 
-	memcpy( (uint8_t*)handle, buffer, length );
-	pthread_mutex_lock( &scsi_task->up_mutex );
-	pthread_cond_signal( &scsi_task->up_cond );
-	pthread_mutex_unlock( &scsi_task->up_mutex );
+	memcpy( (uint8_t *) handle, buffer, length );
+
+	pthread_mutex_lock( &scsi_task->uplink_mutex );
+	pthread_cond_signal( &scsi_task->uplink_cond );
+	pthread_mutex_unlock( &scsi_task->uplink_mutex );
 }
 
 /**
@@ -5325,7 +5350,7 @@ int iscsi_scsi_emu_io_block_read(iscsi_scsi_task *scsi_task, uint8_t *buf, dnbd3
 	iscsi_connection_exec_queue *exec_queue = (iscsi_connection_exec_queue *) malloc( sizeof(struct iscsi_connection_exec_queue) );
 
 	if ( exec_queue == NULL ) {
-		logadd( LOG_ERROR, "iscsi_scsi_emu_io_block_read: Out of memory while allocating execution queue for async I/O" );
+		logadd( LOG_ERROR, "iscsi_scsi_emu_io_block_read: Out of memory while allocating execution queue for I/O read" );
 
 		return -ENOMEM;
 	}
@@ -5337,38 +5362,38 @@ int iscsi_scsi_emu_io_block_read(iscsi_scsi_task *scsi_task, uint8_t *buf, dnbd3
 		readFromFile = true;
 	} else {
 		// This is a proxyed image, check if we need to relay the request...
-		const uint64_t start = offset_bytes & ~(uint64_t)(DNBD3_BLOCK_SIZE - 1);
-		const uint64_t end = (offset_bytes + num_bytes + DNBD3_BLOCK_SIZE - 1) & ~(uint64_t)(DNBD3_BLOCK_SIZE - 1);
+		const uint64_t start = (offset_bytes & ~(uint64_t)(DNBD3_BLOCK_SIZE - 1));
+		const uint64_t end   = ((offset_bytes + num_bytes + DNBD3_BLOCK_SIZE - 1) & ~(uint64_t) (DNBD3_BLOCK_SIZE - 1));
+
 		readFromFile = image_isRangeCachedUnsafe( cache, start, end );
 		ref_put( &cache->reference );
 
 		if ( !readFromFile ) {
 			// Not cached, request via uplink
-			pthread_mutex_init( &scsi_task->up_mutex, NULL );
-			pthread_cond_init( &scsi_task->up_cond, NULL );
-			pthread_mutex_lock( &scsi_task->up_mutex );
-			if ( !uplink_request( image, scsi_task, &iscsi_uplink_callback, (uint64_t)buf, offset_bytes, num_bytes ) ) {
-				pthread_mutex_unlock( &scsi_task->up_mutex );
-				pthread_cond_destroy( &scsi_task->up_cond );
-				pthread_mutex_destroy( &scsi_task->up_mutex );
+			pthread_mutex_lock( &scsi_task->uplink_mutex );
+
+			if ( !uplink_request( image, scsi_task, iscsi_uplink_callback, (uint64_t) buf, offset_bytes, num_bytes ) ) {
+				pthread_mutex_unlock( &scsi_task->uplink_mutex );
+
 				logadd( LOG_DEBUG1, "Could not relay uncached request to upstream proxy for image %s:%d",
 						image->name, image->rid );
+
 				return -EIO;
 			}
+
 			// Wait sync (Maybe use pthread_cond_timedwait to detect unavailable uplink instead of hanging...)
-			pthread_cond_wait( &scsi_task->up_cond, &scsi_task->up_mutex );
-			pthread_mutex_unlock( &scsi_task->up_mutex );
-			pthread_cond_destroy( &scsi_task->up_cond );
-			pthread_mutex_destroy( &scsi_task->up_mutex );
+			pthread_cond_wait( &scsi_task->uplink_cond, &scsi_task->uplink_mutex );
+			pthread_mutex_unlock( &scsi_task->uplink_mutex );
 		}
 	}
 
 	bool success;
+
 	if ( readFromFile ) {
-		const int64_t len          = pread( image->readFd, buf, (size_t) num_bytes, offset_bytes );
-		success                    = ((uint64_t) len == num_bytes);
+		const int64_t len = pread( image->readFd, buf, (size_t) num_bytes, offset_bytes );
+		success           = ((uint64_t) len == num_bytes);
 	} else {
-		success                    = true;
+		success = true;
 	}
 
 	exec_queue->data.io.callback  = callback;
@@ -5527,7 +5552,7 @@ int iscsi_scsi_emu_io_block_write(iscsi_scsi_task *scsi_task, uint8_t *buf, dnbd
 	iscsi_connection_exec_queue *exec_queue = (iscsi_connection_exec_queue *) malloc( sizeof(struct iscsi_connection_exec_queue) );
 
 	if ( exec_queue == NULL ) {
-		logadd( LOG_ERROR, "iscsi_scsi_emu_io_block_read: Out of memory while allocating execution queue for async I/O" );
+		logadd( LOG_ERROR, "iscsi_scsi_emu_io_block_read: Out of memory while allocating execution queue for I/O write" );
 
 		return -ENOMEM;
 	}
@@ -5786,7 +5811,7 @@ static int iscsi_scsi_emu_block_write_same(dnbd3_image_t *image, iscsi_scsi_task
  * @retval true The DNBD3 image has been initialized
  * successfully and is readable.
  * @retval false The DNBD3 image has NOT been
- * successfully and is read is not possible.
+ * successfully and reading is not possible.
  */
 static bool iscsi_scsi_emu_image_init(iscsi_scsi_task *scsi_task, const bool access)
 {
diff --git a/src/server/iscsi.h b/src/server/iscsi.h
index 4c284e0..7ce4122 100644
--- a/src/server/iscsi.h
+++ b/src/server/iscsi.h
@@ -10823,6 +10823,12 @@ typedef struct iscsi_scsi_task {
     /// I/O task wait.
     iscsi_scsi_emu_io_wait io_wait;
 
+    /// Uplink read mutex for sync
+    pthread_mutex_t uplink_mutex;
+
+    /// Conditional to signal uplink read complete
+    pthread_cond_t uplink_cond;
+
     /// Output buffer.
     uint8_t *buf;
 
@@ -10858,12 +10864,6 @@ typedef struct iscsi_scsi_task {
 
     /// Task management response code.
     uint8_t task_mgmt_response;
-
-    /// Uplink read mutex for sync
-    pthread_mutex_t up_mutex;
-
-    /// Conditional to signal uplink read complete
-    pthread_cond_t up_cond;
 } iscsi_scsi_task;