| Message ID | 20250502064930.2981820-5-hch@lst.de |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [1/7] scsi: make aha152x depend on !HIGHMEM | expand |
On Fri, May 02, 2025 at 07:49:21AM +0100, Christoph Hellwig wrote: > usb-storage is the last user of the block layer bounce buffering now, > and only uses it for HCDs that do not support DMA on highmem configs. > > Remove this support and fail the probe so that the block layer bounce > buffering can go away. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/usb/storage/usb.c | 14 +++++++++----- > 1 file changed, 9 insertions(+), 5 deletions(-) > > diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c > index d36f3b6992bb..49bbfe4610d5 100644 > --- a/drivers/usb/storage/usb.c > +++ b/drivers/usb/storage/usb.c > @@ -1057,12 +1057,15 @@ int usb_stor_probe1(struct us_data **pus, > > /* > * 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. > + * We can't support these controllers on highmem systems as the > + * usb-storage code lacks the code to kmap or bounce buffer. > */ > - if (!hcd_uses_dma(bus_to_hcd(us->pusb_dev->bus)) || > - bus_to_hcd(us->pusb_dev->bus)->localmem_pool) > - host->no_highmem = true; > + if (IS_ENABLED(CONFIG_HIGHMEM) && > + (!hcd_uses_dma(bus_to_hcd(us->pusb_dev->bus)) || > + bus_to_hcd(us->pusb_dev->bus)->localmem_pool)) { > + dev_warn(&intf->dev, "USB Mass Storage device not support on this HCD\n"); > + goto release; > + } > > /* Get the unusual_devs entries and the descriptors */ > result = get_device_info(us, id, unusual_dev); > @@ -1081,6 +1084,7 @@ int usb_stor_probe1(struct us_data **pus, > > BadDevice: > usb_stor_dbg(us, "storage_probe() failed\n"); > +release: > release_everything(us); > return result; > } Hopefully this pushes people to use UAS devices instead :) Should be interesting to see the fall-out to see if there are actual systems out there like this still. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On 5/2/25 08:49, Christoph Hellwig wrote: > usb-storage is the last user of the block layer bounce buffering now, > and only uses it for HCDs that do not support DMA on highmem configs. > > Remove this support and fail the probe so that the block layer bounce > buffering can go away. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/usb/storage/usb.c | 14 +++++++++----- > 1 file changed, 9 insertions(+), 5 deletions(-) > Reviewed-by: Hannes Reinecke <hare@suse.de> Cheers, Hannes
On Fri, May 02, 2025 at 09:02:57AM +0200, Greg KH wrote:
> Hopefully this pushes people to use UAS devices instead :)
If usb-storage won't work on a system then UAS won't work either.
Alan Stern
diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c index d36f3b6992bb..49bbfe4610d5 100644 --- a/drivers/usb/storage/usb.c +++ b/drivers/usb/storage/usb.c @@ -1057,12 +1057,15 @@ int usb_stor_probe1(struct us_data **pus, /* * 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. + * We can't support these controllers on highmem systems as the + * usb-storage code lacks the code to kmap or bounce buffer. */ - if (!hcd_uses_dma(bus_to_hcd(us->pusb_dev->bus)) || - bus_to_hcd(us->pusb_dev->bus)->localmem_pool) - host->no_highmem = true; + if (IS_ENABLED(CONFIG_HIGHMEM) && + (!hcd_uses_dma(bus_to_hcd(us->pusb_dev->bus)) || + bus_to_hcd(us->pusb_dev->bus)->localmem_pool)) { + dev_warn(&intf->dev, "USB Mass Storage device not support on this HCD\n"); + goto release; + } /* Get the unusual_devs entries and the descriptors */ result = get_device_info(us, id, unusual_dev); @@ -1081,6 +1084,7 @@ int usb_stor_probe1(struct us_data **pus, BadDevice: usb_stor_dbg(us, "storage_probe() failed\n"); +release: release_everything(us); return result; }
usb-storage is the last user of the block layer bounce buffering now, and only uses it for HCDs that do not support DMA on highmem configs. Remove this support and fail the probe so that the block layer bounce buffering can go away. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/usb/storage/usb.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-)