Problem reported: http://marc.info/?l=dm-devel&m=124585978305866&w=2

scsi_dh does not do a refernce count for attach/detach, and this affects
the way it is supposed to work with multipath when a device is not
in the dev_list of the hardware handler.

This patch adds a reference count that counts each attach.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

No one uses scsi_execute_async with data transfer now. We can remove
scsi_req_map_sg.

Only scsi_eh_lock_door uses scsi_execute_async. scsi_eh_lock_door
doesn't handle sense and the callback. So we can remove
scsi_io_context too.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

scsi_device_online() is not just a negation of SDEV_OFFLINE,
also devices in state SDEV_DEL are actually offline.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Based on prior work by Martin Petersen and James Bottomley, this patch
adds a generic helper for retrieving VPD pages from SCSI devices.
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

scsi_execute() and scsi_execute_req() discard the residual length
information. Some callers need it. This adds residual argument
(optional) to scsi_execute and scsi_execute_req.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

by removing the unused timeout parameter we ensure a compile failure if
anyone is accidentally still using it rather than the block timeout.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

SCSI-ml manages the queueing limits for the device and host, but
does not do so at the target level. However something something similar
can come in userful when a driver is transitioning a transport object to
the the blocked state, becuase at that time we do not want to queue
io and we do not want the queuecommand to be called again.

The patch adds code similar to the exisiting SCSI_ML_*BUSY handlers.
You can now return SCSI_MLQUEUE_TARGET_BUSY when we hit
a transport level queueing issue like the hw cannot allocate some
resource at the iscsi session/connection level, or the target has temporarily
closed or shrunk the queueing window, or if we are transitioning
to the blocked state.

bnx2i, when they rework their firmware according to netdev
developers requests, will also need to be able to limit queueing at this
level. bnx2i will hook into libiscsi, but will allocate a scsi host per
netdevice/hba, so unlike pure software iscsi/iser which is allocating
a host per session, it cannot set the scsi_host->can_queue and return
SCSI_MLQUEUE_HOST_BUSY to reflect queueing limits on the transport.

The iscsi class/driver can also set a scsi_target->can_queue value which
reflects the max commands the driver/class can support. For iscsi this
reflects the number of commands we can support for each session due to
session/connection hw limits, driver limits, and to also reflect the
session/targets's queueing window.

Changes:
v1 - initial patch.
v2 - Fix scsi_run_queue handling of multiple blocked targets.
Previously we would break from the main loop if a device was added back on
the starved list. We now run over the list and check if any target is
blocked.
v3 - Rediff for scsi-misc.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Brian King <brking@linux.vnet.ibm.com> reported that fibre channel
devices can oops during scanning if their ports block (because the
device goes from CREATED -> BLOCK -> RUNNING rather than CREATED ->
BLOCK -> CREATED).

Fix this by adding a new state: CREATED_BLOCK which can only transition
back to CREATED and disallow the CREATED -> BLOCK transition.  Now both
the created and blocked states that the mid-layer recognises can include
CREATED_BLOCK.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

The created and blocked states are very shortly going to correspond to
mixed sdev_state states.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Some USB devices set the protect bit in the INQUIRY data which
currently causes the DIF code in sd to assume (incorrectly) that they
support READ_CAPACITY(16).  Fix this (only for the time being) by
making sure we only believe the protect bit in the inquiry data if the
device claims conformance to SCSI-3 or above.
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

This re-introduces commit 2b142900,
which was reverted due to the regression it caused by commit
fca082c9.

That regression was not root-caused by the original commit, it was just
uncovered by it, and the real fix was done by Alan Stern in commit
580da348 ("Fix USB storage hang on
command abort").

We can thus re-introduce the change that was confirmed by Alan Jenkins
to be still required by his odd card reader.

Cc: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit 2b142900, since it
seems to break some other USB storage devices (at least a JMicron USB to
ATA bridge).  As such, while it apparently fixes some cardreaders, it
would need to be made conditional on the exact reader it fixes in order
to avoid causing regressions.

Cc: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The last_sector_bug flag was added to work around a bug in certain usb
cardreaders, where they would crash if a multiple sector read included the
last sector. The original implementation avoids this by e.g. splitting an 8
sector read which includes the last sector into a 7 sector read, and a single
sector read for the last sector.  The flag is enabled for all USB devices.

This revealed a second bug in other usb cardreaders, which crash when they
get a multiple sector read which stops 1 sector short of the last sector.
Affected hardware includes the Kingston "MobileLite" external USB cardreader
and the internal USB cardreader on the Asus EeePC.

Extend the last_sector_bug workaround to ensure that any access which touches
the last 8 hardware sectors of the device is a single sector long.  Requests
are shrunk as necessary to meet this constraint.

This gives us a safety margin against potential unknown or future bugs
affecting multi-sector access to the end of the device.  The two known bugs
only affect the last 2 sectors.  However, they suggest that these devices
are prone to fencepost errors and that multi-sector access to the end of the
device is not well tested.  Popular OS's use multi-sector accesses, but they
rarely read the last few sectors.  Linux (with udev & vol_id) automatically
reads sectors from the end of the device on insertion.  It is assumed that
single sector accesses are more thoroughly tested during development.
Signed-off-by: NAlan Jenkins <alan-jenkins@tuffmail.co.uk>
Tested-by: NAlan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Implement support for DMA of protection information for devices that
are data integrity capable.

 - Add support for mapping an extra scatter-gather list containing
   the protection information.

 - Allocate protection scsi_data_buffer if host is DIX (integrity DMA)
   capable.

 - Accessor function for checking whether a device has protection
   enabled.
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Instead of having each and every driver implement its own
device table scanning code we should rather implement a common
routine and scan the device tables there.
This allows us also to implement a general notifier chain
callback for all device handler instead for one per handler.

[sekharan: Fix rejections caused by conflicting bug fix]
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Adds a new scsi_device flag, start_stop_pwr_cond:  If enabled, the sd
driver will not send plain START STOP UNIT commands but ones with the
power condition field set to 3 (standby) or 1 (active) respectively.

Some FireWire disk firmwares do not stop the motor if power condition is
zero.  Or worse, they become unresponsive after a START STOP UNIT with
power condition = 0 and start = 0.

http://lkml.org/lkml/2008/4/29/704

This patch only adds the necessary code to sd_mod but doesn't activate
it.  Follow-up patches to the FireWire drivers will add detection of
affected devices and enable the code for them.

I did not add power condition values to scsi_error.c::scsi_eh_try_stu()
for now.  The three firmwares which suffer from above mentioned problems
do not need START STOP UNIT in the error handler, and they are not
adversely affected by START STOP UNIT with power condition = 0 and start
= 1 (like scsi_eh_try_stu() sends it if scsi_device.allow_restart is
enabled).
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: NTino Keitel <tino.keitel@gmx.de>

Some of the storage devices (that can be accessed through multiple paths),
do need some special handling for
	1. Activating the passive path of the storage access.
	2. Decode and handle the special sense codes returned by the devices.
	3. Handle the I/Os being sent to the passive path, especially
           during the device probe time.
when accessed through multiple paths.

As of today this special device handling is done at the dm-multipath
layer using dm-handlers. That works well for (1); for (2) to be handled
at dm layer, scsi sense information need to be exported from SCSI to dm-layer,
which is not very attractive; (3) cannot be done at all at the dm layer.

Device handler has been moved to SCSI mainly to handle (2) and (3) properly.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NMike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

The current target allocation code registeres each possible target
with sysfs; it will be deleted again if no useable LUN on this target
was found. This results in a string of 'target add/target remove' uevents.

Based on a patch by Hannes Reinecke <hare@suse.de> this patch reworks
the target allocation code so that only uevents for existing targets
are sent. The sysfs registration is split off from the existing
scsi_target_alloc() into a in a new scsi_add_target() function, which
should be called whenever an existing target is found. Only then a
uevent is sent, so we'll be generating events for existing targets
only.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

It's big, but there doesn't seem to be a way to split it up smaller...
Signed-off-by: NTony Jones <tonyj@suse.de>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The macro tells us whether the device is (or contains) an enclosure device.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

This patch adds a new scsi_device flag (last_sector_bug) for devices
which contain a bug where the device crashes when the last sector is
read in a larger then 1 sector read.

This is for example the case with sdcards in the HP PSC1350 printer
cardreader and in the HP PSC1610 printer cardreader.
Signed-off-by: NHans de Goede <j.w.r.degoede@hhs.nl>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

The current scsi_test_unit_ready() is updated to return sense code
information (in struct scsi_sense_hdr).  The sd and sr drivers are
changed to interpret the sense code return asc 0x3a as no media and
adjust the device status accordingly.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Some SCSI tape medium changers that need the BLIST_SINGLELUN flag have
the medium changer at one LUN and the tape drive at a different LUN.
The inquiry string of the tape drive may be different from that of the
medium changer.  In order for single_lun to be effective, every
scsi_device under a given scsi_target must have it set.  This means that
there needs to be a blacklist entry for BOTH the medium changer AND the
tape drive, which is impractical because some medium changers may be
paired with a variety of different tape drive models.  It makes more
sense to put the single_lun flag in scsi_target instead of scsi_device,
which causes every device at a given target ID to inherit the single_lun
flag from one LUN.  This makes it possible to blacklist just the medium
changer and not the tape drive.
Signed-off-by: NTony Battersby <tonyb@cybernetics.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

The esp_reset_cleanup() function is called with the host lock held and
invokes starget_for_each_device() which wants to take it too.  Here is a
fix along the lines of shost_for_each_device()/__shost_for_each_device()
adding a __starget_for_each_device() counterpart which assumes the lock
has already been taken.

Eventually, I think the driver should get modified so that more work is
done as a softirq rather than in the interrupt context, but for now it
fixes a bug that causes the spinlock debugger to fire.

While at it, it fixes a small number of cosmetic problems with
starget_for_each_device() too.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Originally based on a patch by Kristen Carlson Accardi @ Intel.
Copious input from James Bottomley.
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Removes an obsolete method scsi_device_cancel which isn't being used
anywhere in the kernel.
Signed-off-by: NPriyanka Gupta <priyankag@google.com>
Acked-by: NGrant Grundler <grundler@parisc-linux.org>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

When reporting SCSI devices to the SCSI midlayer, use the FCP LUN as
LUN reported to the SCSI layer. With this approach, zfcp does not have
to create unique LUNS, and this code can be removed.
Signed-off-by: NChristof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: NSwen Schillig <swen@vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

The following patch adds support for sysfs/uevent modalias
attribute for scsi devices (like disks, tapes, cdroms etc),
based on whatever current sd.c, sr.c, st.c and osst.c drivers
supports.

The modalias format is like this:

 scsi:type-0x04

(for TYPE_WORM, handled by sr.c now).

Several comments.

o This hexadecimal type value is because all TYPE_XXX constants
  in include/scsi/scsi.h are given in hex, but __stringify() will
  not convert them to decimal (so it will NOT be scsi:type-4).
  Since it does not really matter in which format it is, while
  both modalias in module and modalias attribute match each other,
  I descided to go for that 0x%02x format (and added a comment in
  include/scsi/scsi.h to keep them that way), instead of changing
  them all to decimal.

o There was no .uevent routine for SCSI bus.  It might be a good
  idea to add some more ueven environment variables in there.

o osst.c driver handles tapes too, like st.c, but only SOME tapes.
  With this setup, hotplug scripts (or whatever is used by the
  user) will try to load both st and osst modules for all SCSI
  tapes found, because both modules have scsi:type-0x01 alias).
  It is not harmful, but one extra module is no good either.
  It is possible to solve this, by exporting more info in
  modalias attribute, including vendor and device identification
  strings, so that modalias becomes something like
    scsi:type-0x12:vendor-Adaptec LTD:device-OnStream Tape Drive
  and having that, match for all 3 attributes, not only device
  type.  But oh well, vendor and device strings may be large,
  and they do contain spaces and whatnot.
  So I left them for now, awaiting for comments first.
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Implement SBC START/STOP management.  sdev->mange_start_stop is added.
When it's set to one, sd STOPs the device on suspend and shutdown and
STARTs it on resume.  sdev->manage_start_stop defaults is in sdev
instead of scsi_disk cdev to allow ->slave_config() override the
default configuration but is exported under scsi_disk sysfs node as
sdev->allow_restart is.

When manage_start_stop is zero (the default value), this patch doesn't
introduce any behavior change.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Rejections fixed and
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This patch enhances SCSI error printing by:

 - Making use of scsi_print_result() in the completion functions.

 - Having scmd_printk() output the disk name (when applicable).
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

there's a USB mass storage device which exists in two version. One
reports the correct size and the other does not. Apart from that they
are identical and cannot be told apart. Here's a heuristic based on the
empirical finding that drives have even sizes.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NMatthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Since it often takes around 20-30 seconds to scan a scsi bus, it's
highly advantageous to do this in parallel with other things.  The bulk
of this patch is ensuring that devices don't change numbering, and that
all devices are discovered prior to trying to start init.  For those
who build SCSI as modules, there's a new scsi_wait_scan module that will
ensure all bus scans are finished.

This patch only handles drivers which call scsi_scan_host.  Fibre Channel,
SAS, SATA, USB and Firewire all need additional work.
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

device_reprobe() should return an error code.  When it does so,
scsi_device_reprobe() should propagate it back.
Acked-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

device_reprobe() should return an error code.  When it does so,
scsi_device_reprobe() should propagate it back.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This complements the scsi_mode_sense() function
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Original from Christoph Hellwig and Eric Moore.  This version exports
the scsi_reprobe_device() function as an inline.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

In order to use the new execute_in_process_context() API, you have to
provide it with the work storage, which I do in SCSI in scsi_device and
scsi_target, but which also means that we can no longer queue up the
target reaps, so instead I moved the target to a state model which
allows target_alloc to detect if we've received a dying target and wait
for it to be gone.  Hopefully, this should also solve the target
namespace race.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Some non-standard SCSI targets or protocols, such as USB UFI, report "no
LUN present" by setting the Peripheral Device Type to 0x1f and the
Peripheral Qualifier to 0 (not 3 as the standard requires) in the INQUIRY
response.  This patch (as650b) adds a new target flag and code to
accomodate such targets.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

As devfs has been disabled from the kernel tree for a number of months
now (5 to be exact), here's a patch against 2.6.16-rc1-git1 that removes
support for it from the SCSI subsystem.

The patch also removes the scsi_disk devfs_name field as it's no longer
needed.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

When the scsi_execute_async interface was added it ended up reducing
the flexibility of userspace to send arbitrary scsi commands through
sg using SG_IO. The SG_IO interface allows userspace to specify the
CDB length. This is now ignored in scsi_execute_async and it is
guessed using the COMMAND_SIZE macro, which is not always correct,
particularly for vendor specific commands. This patch adds a cmd_len
parameter to the scsi_execute_async interface to allow the caller
to specify the length of the CDB.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>