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authorDoug Maxey <dwm@enoyolf.org>2007-12-05 23:36:45 -0600
committerGreg Kroah-Hartman <gregkh@suse.de>2007-12-17 10:47:14 -0800
commit33abc04f0420dceed0ebc2d1094019d3bb2b5c29 (patch)
tree87d8e2c7cf41d6afed4d75c2e3ef113b506541ab
parentb9e13ac30f850313be9232497ff98e90c43bc6b6 (diff)
usb-storage: Fix devices that cannot handle 32k transfers
When a device cannot handle the smallest previously limited transfer size (64 blocks) without stalling, limit the device to the amount of packets that fit in a platform native page. The lowest possible limit is PAGE_CACHE_SIZE, so if the device is ever used on a platform that has larger than 8K pages, you lose unless you can convince the device firmware folks to fix the issue. Cc: Mathew Dharm <mdharm-scsi@one-eyed-alien.net> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Pete Zaitcev <zaitcev@redhat.com> Signed-off-by: Doug Maxey <dwm@austin.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r--drivers/usb/storage/scsiglue.c12
-rw-r--r--drivers/usb/storage/unusual_devs.h7
-rw-r--r--include/linux/usb_usual.h5
3 files changed, 20 insertions, 4 deletions
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index 836a34ae6ec6..7c9593b7b04e 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -114,9 +114,15 @@ static int slave_configure(struct scsi_device *sdev)
* while others have trouble with more than 64K. At this time we
* are limiting both to 32K (64 sectores).
*/
- if ((us->flags & US_FL_MAX_SECTORS_64) &&
- sdev->request_queue->max_sectors > 64)
- blk_queue_max_sectors(sdev->request_queue, 64);
+ if (us->flags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
+ unsigned int max_sectors = 64;
+
+ if (us->flags & US_FL_MAX_SECTORS_MIN)
+ max_sectors = PAGE_CACHE_SIZE >> 9;
+ if (sdev->request_queue->max_sectors > max_sectors)
+ blk_queue_max_sectors(sdev->request_queue,
+ max_sectors);
+ }
/* 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/unusual_devs.h b/drivers/usb/storage/unusual_devs.h
index 2c27721bd259..7bbfd31a9645 100644
--- a/drivers/usb/storage/unusual_devs.h
+++ b/drivers/usb/storage/unusual_devs.h
@@ -376,6 +376,13 @@ UNUSUAL_DEV( 0x04b0, 0x0417, 0x0100, 0x0100,
US_SC_DEVICE, US_PR_DEVICE, NULL,
US_FL_FIX_CAPACITY),
+/* Reported by Doug Maxey (dwm@austin.ibm.com) */
+UNUSUAL_DEV( 0x04b3, 0x4001, 0x0110, 0x0110,
+ "IBM",
+ "IBM RSA2",
+ US_SC_DEVICE, US_PR_CB, NULL,
+ US_FL_MAX_SECTORS_MIN),
+
/* BENQ DC5330
* Reported by Manuel Fombuena <mfombuena@ya.com> and
* Frank Copeland <fjc@thingy.apana.org.au> */
diff --git a/include/linux/usb_usual.h b/include/linux/usb_usual.h
index 1b792b9286ba..a417b09b8b3d 100644
--- a/include/linux/usb_usual.h
+++ b/include/linux/usb_usual.h
@@ -48,7 +48,10 @@
US_FLAG(IGNORE_DEVICE, 0x00000800) \
/* Don't claim device */ \
US_FLAG(CAPACITY_HEURISTICS, 0x00001000) \
- /* sometimes sizes is too big */
+ /* sometimes sizes is too big */ \
+ US_FLAG(MAX_SECTORS_MIN,0x00002000) \
+ /* Sets max_sectors to arch min */
+
#define US_FLAG(name, value) US_FL_##name = value ,
enum { US_DO_ALL_FLAGS };