scsi: core: Add a no_highmem flag to struct Scsi_Host

While we really should be killing the block layer bounce buffering ASAP, I
even more urgently need to stop the drivers to fiddle with the limits from
->slave_configure.  Add a no_highmem flag to the Scsi_Host to centralize
this setting and switch the remaining four drivers that use block layer
bounce buffering to it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240409143748.980206-7-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 1 insertions, 11 deletions

diff --git a/drivers/scsi/imm.c b/drivers/scsi/imm.c
index 180a5ddedb2c..21339da505f1 100644
--- a/drivers/scsi/imm.c
+++ b/drivers/scsi/imm.c
@@ -1100,16 +1100,6 @@ static int device_check(imm_struct *dev, bool autodetect)
 	return -ENODEV;
 }
 
-/*
- * imm cannot deal with highmem, so this causes all IO pages for this host
- * to reside in low memory (hence mapped)
- */
-static int imm_adjust_queue(struct scsi_device *device)
-{
-	blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH);
-	return 0;
-}
-
 static const struct scsi_host_template imm_template = {
 	.module			= THIS_MODULE,
 	.proc_name		= "imm",
@@ -1123,7 +1113,6 @@ static const struct scsi_host_template imm_template = {
 	.this_id		= 7,
 	.sg_tablesize		= SG_ALL,
 	.can_queue		= 1,
-	.slave_alloc		= imm_adjust_queue,
 	.cmd_size		= sizeof(struct scsi_pointer),
 };
 
@@ -1235,6 +1224,7 @@ static int __imm_attach(struct parport *pb)
 	host = scsi_host_alloc(&imm_template, sizeof(imm_struct *));
 	if (!host)
 		goto out1;
+	host->no_highmem = true;
 	host->io_port = pb->base;
 	host->n_io_port = ports;
 	host->dma_channel = -1;