[PATCH] sbp2: add read_capacity workaround for iPod
Apple decided to copy some USB stupidity over to FireWire.
The sector number returned by iPods from read_capacity is one too many.
This may cause I/O errors, especially if the kernel is configured for EFI
partition support. We use the same workaround as usb-storage but have to
check for different model IDs.
http://marc.theaimsgroup.com/?t=114233262300001
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=187409
Acknowledgements:
Diagnosis and therapy by Mathieu Chouquet-Stringer <ml2news@free.fr>,
additional data about affected and unaffected Apple hardware from
Vladimir Kotal, Sander De Graaf, Bryan Olmstead and Hugh Dixon.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/ieee1394/sbp2.c b/drivers/ieee1394/sbp2.c
index ecd59ef..09e9291 100644
--- a/drivers/ieee1394/sbp2.c
+++ b/drivers/ieee1394/sbp2.c
@@ -151,6 +151,11 @@
* - skip mode page 8
* Suppress sending of mode_sense for mode page 8 if the device pretends to
* support the SCSI Primary Block commands instead of Reduced Block Commands.
+ *
+ * - fix capacity
+ * Tell sd_mod to correct the last sector number reported by read_capacity.
+ * Avoids access beyond actual disk limits on devices with an off-by-one bug.
+ * Don't use this with devices which don't have this bug.
*/
static int sbp2_default_workarounds;
module_param_named(workarounds, sbp2_default_workarounds, int, 0644);
@@ -158,6 +163,7 @@
", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
", 36 byte inquiry = " __stringify(SBP2_WORKAROUND_INQUIRY_36)
", skip mode page 8 = " __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
+ ", fix capacity = " __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
", or a combination)");
/* legacy parameter */
@@ -291,6 +297,7 @@
*/
static const struct {
u32 firmware_revision;
+ u32 model_id;
unsigned workarounds;
} sbp2_workarounds_table[] = {
/* TSB42AA9 */ {
@@ -305,6 +312,31 @@
/* Symbios bridge */ {
.firmware_revision = 0xa0b800,
.workarounds = SBP2_WORKAROUND_128K_MAX_TRANS,
+ },
+ /*
+ * Note about the following Apple iPod blacklist entries:
+ *
+ * There are iPods (2nd gen, 3rd gen) with model_id==0. Since our
+ * matching logic treats 0 as a wildcard, we cannot match this ID
+ * without rewriting the matching routine. Fortunately these iPods
+ * do not feature the read_capacity bug according to one report.
+ * Read_capacity behaviour as well as model_id could change due to
+ * Apple-supplied firmware updates though.
+ */
+ /* iPod 4th generation */ {
+ .firmware_revision = 0x0a2700,
+ .model_id = 0x000021,
+ .workarounds = SBP2_WORKAROUND_FIX_CAPACITY,
+ },
+ /* iPod mini */ {
+ .firmware_revision = 0x0a2700,
+ .model_id = 0x000023,
+ .workarounds = SBP2_WORKAROUND_FIX_CAPACITY,
+ },
+ /* iPod Photo */ {
+ .firmware_revision = 0x0a2700,
+ .model_id = 0x00007e,
+ .workarounds = SBP2_WORKAROUND_FIX_CAPACITY,
}
};
@@ -1556,18 +1588,25 @@
}
for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
- if (sbp2_workarounds_table[i].firmware_revision !=
+ if (sbp2_workarounds_table[i].firmware_revision &&
+ sbp2_workarounds_table[i].firmware_revision !=
(firmware_revision & 0xffff00))
continue;
+ if (sbp2_workarounds_table[i].model_id &&
+ sbp2_workarounds_table[i].model_id != ud->model_id)
+ continue;
workarounds |= sbp2_workarounds_table[i].workarounds;
break;
}
if (workarounds)
- SBP2_INFO("Workarounds for node " NODE_BUS_FMT ": "
- "0x%x (firmware_revision 0x%x)",
+ SBP2_INFO("Workarounds for node " NODE_BUS_FMT ": 0x%x "
+ "(firmware_revision 0x%06x, vendor_id 0x%06x,"
+ " model_id 0x%06x)",
NODE_BUS_ARGS(ud->ne->host, ud->ne->nodeid),
- workarounds, firmware_revision);
+ workarounds, firmware_revision,
+ ud->vendor_id ? ud->vendor_id : ud->ne->vendor_id,
+ ud->model_id);
/* We would need one SCSI host template for each target to adjust
* max_sectors on the fly, therefore warn only. */
@@ -2488,6 +2527,8 @@
if (sdev->type == TYPE_DISK &&
scsi_id->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
sdev->skip_ms_page_8 = 1;
+ if (scsi_id->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
+ sdev->fix_capacity = 1;
return 0;
}