ide: kill ide_toggle_bounce

ide_toggle_bounce did select various strange block bounce limits, including
not bouncing at all as soon as an iommu is present in the system. Given
that the dma_map routines now handle any required bounce buffering except
for ISA DMA, and the ide code already must handle either ISA DMA or highmem
at least for iommu equipped systems we can get rid of the block layer
bounce limit setting entirely.

Signed-off-by: Christoph Hellwig <[e-mail]>
Reviewed-by: Jens Axboe <[e-mail]>

drivers/ide/ide-dma.c

···
 void ide_dma_off_quietly(ide_drive_t *drive)
 {
 	drive->dev_flags &= ~IDE_DFLAG_USING_DMA;
-	ide_toggle_bounce(drive, 0);
 
 	drive->hwif->dma_ops->dma_host_set(drive, 0);
 }
···
 void ide_dma_on(ide_drive_t *drive)
 {
 	drive->dev_flags |= IDE_DFLAG_USING_DMA;
-	ide_toggle_bounce(drive, 1);
 
 	drive->hwif->dma_ops->dma_host_set(drive, 1);
 }

drivers/ide/ide-lib.c

···
 #include <linux/ide.h>
 #include <linux/bitops.h>
 
-/**
- *	ide_toggle_bounce	-	handle bounce buffering
- *	@drive: drive to update
- *	@on: on/off boolean
- *
- *	Enable or disable bounce buffering for the device. Drives move
- *	between PIO and DMA and that changes the rules we need.
- */
-
-void ide_toggle_bounce(ide_drive_t *drive, int on)
-{
-	u64 addr = BLK_BOUNCE_HIGH;	/* dma64_addr_t */
-
-	if (!PCI_DMA_BUS_IS_PHYS) {
-		addr = BLK_BOUNCE_ANY;
-	} else if (on && drive->media == ide_disk) {
-		struct device *dev = drive->hwif->dev;
-
-		if (dev && dev->dma_mask)
-			addr = *dev->dma_mask;
-	}
-
-	if (drive->queue)
-		blk_queue_bounce_limit(drive->queue, addr);
-}
-
 u64 ide_get_lba_addr(struct ide_cmd *cmd, int lba48)
 {
 	struct ide_taskfile *tf = &cmd->tf;

drivers/ide/ide-probe.c

···
 	/* assign drive queue */
 	drive->queue = q;
 
-	/* needs drive->queue to be set */
-	ide_toggle_bounce(drive, 1);
-
 	return 0;
 }
 

include/linux/ide.h

···
 	hwif->hwif_data = data;
 }
 
-extern void ide_toggle_bounce(ide_drive_t *drive, int on);
-
 u64 ide_get_lba_addr(struct ide_cmd *, int);
 u8 ide_dump_status(ide_drive_t *, const char *, u8);