[PATCH 06/23] scsi: add a no_highmem flag to struct Scsi_Host

Christoph Hellwig
2024-04-09T14:38:18Z

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>
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>
---
drivers/scsi/aha152x.c | 8 +-------
drivers/scsi/imm.c | 12 +-----------
drivers/scsi/ppa.c | 8 +-------
drivers/scsi/scsi_lib.c | 3 +++
drivers/usb/storage/scsiglue.c | 10 ----------
drivers/usb/storage/usb.c | 10 ++++++++++
include/scsi/scsi_host.h | 2 ++
7 files changed, 18 insertions(+), 35 deletions(-)

diff --git a/drivers/scsi/aha152x.c b/drivers/scsi/aha152x.c
index 055adb349b0e41..83f16fc14d9630 100644
--- a/drivers/scsi/aha152x.c
+++ b/drivers/scsi/aha152x.c
@@ -746,6 +746,7 @@ struct Scsi_Host *aha152x_probe_one(struct aha152x_setup *setup)
/* need to have host registered before triggering any interrupt */
list_add_tail(&HOSTDATA(shpnt)->host_list, &aha152x_host_list);

+ shpnt->no_highmem = true;
shpnt->io_port = setup->io_port;
shpnt->n_io_port = IO_RANGE;
shpnt->irq = setup->irq;
@@ -2940,12 +2941,6 @@ static int aha152x_show_info(struct seq_file *m, struct Scsi_Host *shpnt)
return 0;
}

-static int aha152x_adjust_queue(struct scsi_device *device)
-{
- blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH);
- return 0;
-}
-
static const struct scsi_host_template aha152x_driver_template = {
.module = THIS_MODULE,
.name = AHA152X_REVID,
@@ -2961,7 +2956,6 @@ static const struct scsi_host_template aha152x_driver_template = {
.this_id = 7,
.sg_tablesize = SG_ALL,
.dma_boundary = PAGE_SIZE - 1,
- .slave_alloc = aha152x_adjust_queue,
.cmd_size = sizeof(struct aha152x_cmd_priv),
};

diff --git a/drivers/scsi/imm.c b/drivers/scsi/imm.c
index 180a5ddedb2cda..21339da505f1ea 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;
diff --git a/drivers/scsi/ppa.c b/drivers/scsi/ppa.c
index d592ee9170c11f..8300f0bdddb37a 100644
--- a/drivers/scsi/ppa.c
+++ b/drivers/scsi/ppa.c
@@ -986,12 +986,6 @@ static int device_check(ppa_struct *dev, bool autodetect)
return -ENODEV;
}

-static int ppa_adjust_queue(struct scsi_device *device)
-{
- blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH);
- return 0;
-}
-
static const struct scsi_host_template ppa_template = {
.module = THIS_MODULE,
.proc_name = "ppa",
@@ -1005,7 +999,6 @@ static const struct scsi_host_template ppa_template = {
.this_id = -1,
.sg_tablesize = SG_ALL,
.can_queue = 1,
- .slave_alloc = ppa_adjust_queue,
.cmd_size = sizeof(struct scsi_pointer),
};

@@ -1111,6 +1104,7 @@ static int __ppa_attach(struct parport *pb)
host = scsi_host_alloc(&ppa_template, sizeof(ppa_struct *));
if (!host)
goto out1;
+ host->no_highmem = true;
host->io_port = pb->base;
host->n_io_port = ports;
host->dma_channel = -1;
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 1deca84914e87a..f1936f98abe3e2 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1995,6 +1995,9 @@ void scsi_init_limits(struct Scsi_Host *shost, struct queue_limits *lim)
*/
lim->dma_alignment = max(4, dma_get_cache_alignment()) - 1;

+ if (shost->no_highmem)
+ lim->bounce = BLK_BOUNCE_HIGH;
+
dma_set_seg_boundary(dev, shost->dma_boundary);
dma_set_max_seg_size(dev, shost->max_segment_size);
}
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index 12cf9940e5b675..1d14c678f3d3e3 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -40,7 +40,6 @@
#include <scsi/scsi_eh.h>

#include "usb.h"
-#include <linux/usb/hcd.h>
#include "scsiglue.h"
#include "debug.h"
#include "transport.h"
@@ -130,15 +129,6 @@ static int slave_configure(struct scsi_device *sdev)
min_t(size_t, queue_max_hw_sectors(sdev->request_queue),
dma_max_mapping_size(dev) >> SECTOR_SHIFT));

- /*
- * Some USB host controllers can't do DMA; they have to use PIO.
- * For such controllers we need to make sure the block layer sets
- * up bounce buffers in addressable memory.
- */
- if (!hcd_uses_dma(bus_to_hcd(us->pusb_dev->bus)) ||
- (bus_to_hcd(us->pusb_dev->bus)->localmem_pool != NULL))
- blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
-
/*
* We can't put these settings in slave_alloc() because that gets
* called before the device type is known. Consequently these
diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index d1ad6a2509ab7f..a49a31639f6f0c 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -47,6 +47,7 @@
#include <scsi/scsi_device.h>

#include "usb.h"
+#include <linux/usb/hcd.h>
#include "scsiglue.h"
#include "transport.h"
#include "protocol.h"
@@ -961,6 +962,15 @@ int usb_stor_probe1(struct us_data **pus,
if (result)
goto BadDevice;

+ /*
+ * Some USB host controllers can't do DMA; they have to use PIO.
+ * For such controllers we need to make sure the block layer sets
+ * up bounce buffers in addressable memory.
+ */
+ if (!hcd_uses_dma(bus_to_hcd(us->pusb_dev->bus)) ||
+ bus_to_hcd(us->pusb_dev->bus)->localmem_pool)
+ host->no_highmem = true;
+
/* Get the unusual_devs entries and the descriptors */
result = get_device_info(us, id, unusual_dev);
if (result)
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index b259d42a1e1aff..6d77c48e8311fb 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -665,6 +665,8 @@ struct Scsi_Host {
/* The transport requires the LUN bits NOT to be stored in CDB[1] */
unsigned no_scsi2_lun_in_cdb:1;

+ unsigned no_highmem:1;
+
/*
* Optional work queue to be utilized by the transport
*/
--
2.39.2