Addition of write support to the disk device manager. Courtesy of Tomas

Kucera and Jan Matejek.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@21719 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/disk_device_manager/KDiskDeviceJob.h

@@ -4,6 +4,7 @@
 #define _K_DISK_DEVICE_JOB_H
 
 #include "disk_device_manager.h"
+#include <KPartitionVisitor.h>
 
 struct user_disk_device_job_info;
 
@@ -12,19 +13,41 @@ namespace DiskDevice {
 
 class KDiskDeviceJobQueue;
 
+/**
+ * Represents some action executed on the disk device.
+ * 
+ * - 
+ */
 class KDiskDeviceJob {
 public:
+	/**
+	 * Creates a new job
+	 * 
+	 * \param type actual type of the job (see DiskDeviceDefs.h for details)
+	 * \param partitionID the partition/device on which the action should be executed
+	 * \param scopeID partition/device which is the highest in the hierarchy (i.e. closest
+	 * to the root) that can be affected by the action
+ * 		- every descendant of this partition is marked busy and all ancestors are marked descendant-
+	busy
+	 */
 	KDiskDeviceJob(uint32 type, partition_id partitionID,
 				   partition_id scopeID = -1);
 	virtual ~KDiskDeviceJob();
 
+	/**
+	 * Unique identification of the job
+	 */
 	disk_job_id ID() const;
 
 	void SetJobQueue(KDiskDeviceJobQueue *queue);
 	KDiskDeviceJobQueue *JobQueue() const;
 
+	/**
+	 * Gets actual type of the action
+	 */
 	uint32 Type() const;
 
+	
 	void SetStatus(uint32 status);
 	uint32 Status() const;
 
@@ -54,9 +77,25 @@ public:
 		// triggers a notification
 	float Progress() const;
 
+	
 	status_t GetInfo(user_disk_device_job_info *info);
 	status_t GetProgressInfo(disk_device_job_progress_info *info);
 
+	/**
+	 * Do the actual work of the job.
+	 * 
+	 * - is supposed to be implemented in descendants
+	 * - doesn't have any parameter - every operation needs different ones -> they're passed
+	 * 		to the constructor
+	 * - the implementations will 
+	 * 		- check the parameters given in constructor (e.g. if given partition exists...)
+	 * 		- check whether the partition has needed disk system (its own or parent - depends
+	 * 			on the operation)
+	 * 		- using the disk system, validate the operation for given params
+	 * 		- finally execute the action
+	 * 
+	 * \return B_OK when everything went OK, some error otherwise
+	 */
 	virtual status_t Do() = 0;
 
 private:
@@ -76,6 +115,29 @@ private:
 	float				fProgress;
 
 	static disk_job_id	fNextID;
+	
+private:
+	/**
+	 * Visitor which checks if every descendant of given partition is busy or descendant-busy
+	 */
+	struct IsNotBusyVisitor	: KPartitionVisitor {
+		virtual bool VisitPre(KPartition * partition);
+	};
+	IsNotBusyVisitor fNotBusyVisitor;
+	
+protected: 
+	//some stuff useful for all descendants
+		
+	/**
+	 * Checks if there's any descendant which is not busy/descendant-busy.
+	 * 
+	 * - the condition of busy descendant is common for many disk device operations ->
+	 * 		many jobs can use this
+	 * 
+	 * \param partition the root of checked subtree of the whole partition hieararchy
+	 */
+	bool isPartitionNotBusy( KPartition * partition );	
+	
 };
 
 } // namespace DiskDevice