lib: allow block device file use for tests

Allow using a block device file to be specified for running tests by
suppressing the block backend driver when opening the device. Doing so,
the block device file will be used to pass either SCSI or ATA commands
to the disk using the SCSI or ATA backends.

Signed-off-by: Damien Le Moal <[email protected]>

Author: damien-lemoal

lib/zbc.c

@@ -340,15 +340,20 @@ int zbc_open(const char *filename, int flags, struct zbc_device **pdev)
 	struct zbc_device *dev = NULL;
 	unsigned int allowed_drv;
 	char *path = NULL;
-	int ret, i;
+	int ret, i, mask = ZBC_O_DRV_MASK;
 
 	ret = zbc_realpath(filename, &path);
 	if (ret)
 		return ret;
 
-	allowed_drv = flags & ZBC_O_DRV_MASK;
+#ifdef HAVE_DEVTEST
+	if (flags & ZBC_O_DEVTEST)
+		mask = ZBC_O_TEST_DRV_MASK;
+#endif
+
+	allowed_drv = flags & mask;
 	if (!allowed_drv)
-		allowed_drv = ZBC_O_DRV_MASK;
+		allowed_drv = mask;
 
 	/* Test all backends until one accepts the drive */
 	ret = -ENODEV;

lib/zbc.h

@@ -175,6 +175,8 @@ static inline void zbc_set_errno(enum zbc_sk sk, enum zbc_asc_ascq asc_ascq)
 #define ZBC_O_DMODE_MASK	(ZBC_O_MODE_MASK | O_DIRECT)
 #define ZBC_O_DRV_MASK		(ZBC_O_DRV_BLOCK | ZBC_O_DRV_SCSI | \
 				 ZBC_O_DRV_ATA | ZBC_O_DRV_FAKE)
+#define ZBC_O_TEST_DRV_MASK	(ZBC_O_DRV_SCSI | ZBC_O_DRV_ATA | \
+				 ZBC_O_DRV_FAKE)
 
 /**
  * Test if a device is in test mode.