[PATCH] libata: Add some dummy noop functions

Add some dummy noop functions for use by libata clients
that do not need to do anything. Future SAS patches will
utilize these functions.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/scsi/libata-core.c

@@ -2865,6 +2865,8 @@ void ata_qc_prep(struct ata_queued_cmd *qc)
 	ata_fill_sg(qc);
 }
 
+void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
+
 /**
  *	ata_sg_init_one - Associate command with memory buffer
  *	@qc: Command to be associated
@@ -5063,6 +5065,7 @@ EXPORT_SYMBOL_GPL(ata_port_stop);
 EXPORT_SYMBOL_GPL(ata_host_stop);
 EXPORT_SYMBOL_GPL(ata_interrupt);
 EXPORT_SYMBOL_GPL(ata_qc_prep);
+EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
 EXPORT_SYMBOL_GPL(ata_bmdma_setup);
 EXPORT_SYMBOL_GPL(ata_bmdma_start);
 EXPORT_SYMBOL_GPL(ata_bmdma_irq_clear);

include/linux/libata.h

@@ -543,6 +543,7 @@ extern void ata_port_stop (struct ata_port *ap);
 extern void ata_host_stop (struct ata_host_set *host_set);
 extern irqreturn_t ata_interrupt (int irq, void *dev_instance, struct pt_regs *regs);
 extern void ata_qc_prep(struct ata_queued_cmd *qc);
+extern void ata_noop_qc_prep(struct ata_queued_cmd *qc);
 extern unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc);
 extern void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf,
 		unsigned int buflen);