linux-stable/include/linux/usb_usual.h
Alan Stern 546aa0e4ea usb-storage: Add quirk to defeat Kindle's automatic unload
Matthias reports that the Amazon Kindle automatically removes its
emulated media if it doesn't receive another SCSI command within about
one second after a SYNCHRONIZE CACHE.  It does so even when the host
has sent a PREVENT MEDIUM REMOVAL command.  The reason for this
behavior isn't clear, although it's not hard to make some guesses.

At any rate, the results can be unexpected for anyone who tries to
access the Kindle in an unusual fashion, and in theory they can lead
to data loss (for example, if one file is closed and synchronized
while other files are still in the middle of being written).

To avoid such problems, this patch creates a new usb-storage quirks
flag telling the driver always to issue a REQUEST SENSE following a
SYNCHRONIZE CACHE command, and adds an unusual_devs entry for the
Kindle with the flag set.  This is sufficient to prevent the Kindle
from doing its automatic unload, without interfering with proper
operation.

Another possible way to deal with this would be to increase the
frequency of TEST UNIT READY polling that the kernel normally carries
out for removable-media storage devices.  However that would increase
the overall load on the system and it is not as reliable, because the
user can override the polling interval.  Changing the driver's
behavior is safer and has minimal overhead.

CC: <stable@vger.kernel.org>
Reported-and-tested-by: Matthias Schwarzott <zzam@gentoo.org>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20210317190654.GA497856@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-17 21:30:15 +01:00

101 lines
3.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Interface to the libusual.
*
* Copyright (c) 2005 Pete Zaitcev <zaitcev@redhat.com>
* Copyright (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
* Copyright (c) 1999 Michael Gee (michael@linuxspecific.com)
*/
#ifndef __LINUX_USB_USUAL_H
#define __LINUX_USB_USUAL_H
/* We should do this for cleanliness... But other usb_foo.h do not do this. */
/* #include <linux/usb.h> */
/*
* The flags field, which we store in usb_device_id.driver_info.
* It is compatible with the old usb-storage flags in lower 24 bits.
*/
/*
* Static flag definitions. We use this roundabout technique so that the
* proc_info() routine can automatically display a message for each flag.
*/
#define US_DO_ALL_FLAGS \
US_FLAG(SINGLE_LUN, 0x00000001) \
/* allow access to only LUN 0 */ \
US_FLAG(NEED_OVERRIDE, 0x00000002) \
/* unusual_devs entry is necessary */ \
US_FLAG(SCM_MULT_TARG, 0x00000004) \
/* supports multiple targets */ \
US_FLAG(FIX_INQUIRY, 0x00000008) \
/* INQUIRY response needs faking */ \
US_FLAG(FIX_CAPACITY, 0x00000010) \
/* READ CAPACITY response too big */ \
US_FLAG(IGNORE_RESIDUE, 0x00000020) \
/* reported residue is wrong */ \
US_FLAG(BULK32, 0x00000040) \
/* Uses 32-byte CBW length */ \
US_FLAG(NOT_LOCKABLE, 0x00000080) \
/* PREVENT/ALLOW not supported */ \
US_FLAG(GO_SLOW, 0x00000100) \
/* Need delay after Command phase */ \
US_FLAG(NO_WP_DETECT, 0x00000200) \
/* Don't check for write-protect */ \
US_FLAG(MAX_SECTORS_64, 0x00000400) \
/* Sets max_sectors to 64 */ \
US_FLAG(IGNORE_DEVICE, 0x00000800) \
/* Don't claim device */ \
US_FLAG(CAPACITY_HEURISTICS, 0x00001000) \
/* sometimes sizes is too big */ \
US_FLAG(MAX_SECTORS_MIN,0x00002000) \
/* Sets max_sectors to arch min */ \
US_FLAG(BULK_IGNORE_TAG,0x00004000) \
/* Ignore tag mismatch in bulk operations */ \
US_FLAG(SANE_SENSE, 0x00008000) \
/* Sane Sense (> 18 bytes) */ \
US_FLAG(CAPACITY_OK, 0x00010000) \
/* READ CAPACITY response is correct */ \
US_FLAG(BAD_SENSE, 0x00020000) \
/* Bad Sense (never more than 18 bytes) */ \
US_FLAG(NO_READ_DISC_INFO, 0x00040000) \
/* cannot handle READ_DISC_INFO */ \
US_FLAG(NO_READ_CAPACITY_16, 0x00080000) \
/* cannot handle READ_CAPACITY_16 */ \
US_FLAG(INITIAL_READ10, 0x00100000) \
/* Initial READ(10) (and others) must be retried */ \
US_FLAG(WRITE_CACHE, 0x00200000) \
/* Write Cache status is not available */ \
US_FLAG(NEEDS_CAP16, 0x00400000) \
/* cannot handle READ_CAPACITY_10 */ \
US_FLAG(IGNORE_UAS, 0x00800000) \
/* Device advertises UAS but it is broken */ \
US_FLAG(BROKEN_FUA, 0x01000000) \
/* Cannot handle FUA in WRITE or READ CDBs */ \
US_FLAG(NO_ATA_1X, 0x02000000) \
/* Cannot handle ATA_12 or ATA_16 CDBs */ \
US_FLAG(NO_REPORT_OPCODES, 0x04000000) \
/* Cannot handle MI_REPORT_SUPPORTED_OPERATION_CODES */ \
US_FLAG(MAX_SECTORS_240, 0x08000000) \
/* Sets max_sectors to 240 */ \
US_FLAG(NO_REPORT_LUNS, 0x10000000) \
/* Cannot handle REPORT_LUNS */ \
US_FLAG(ALWAYS_SYNC, 0x20000000) \
/* lies about caching, so always sync */ \
US_FLAG(NO_SAME, 0x40000000) \
/* Cannot handle WRITE_SAME */ \
US_FLAG(SENSE_AFTER_SYNC, 0x80000000) \
/* Do REQUEST_SENSE after SYNCHRONIZE_CACHE */ \
#define US_FLAG(name, value) US_FL_##name = value ,
enum { US_DO_ALL_FLAGS };
#undef US_FLAG
#include <linux/usb/storage.h>
extern int usb_usual_ignore_device(struct usb_interface *intf);
extern const struct usb_device_id usb_storage_usb_ids[];
#endif /* __LINUX_USB_USUAL_H */