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: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
> BUG: unable to handle kernel paging request at e6f17fac
> IP: [<c02604d6>] scsi_bus_uevent+0x1/0x17
> *pde = 2714b163 *pte = 26f17160
> Oops: 0000 [#1] DEBUG_PAGEALLOC
> last sysfs file:
>
> Pid: 1, comm: swapper Not tainted (2.6.26-rc2-next-20080516skw #30)
> EIP: 0060:[<c02604d6>] EFLAGS: 00010282 CPU: 0
> EIP is at scsi_bus_uevent+0x1/0x17
> EAX: e6f18014 EBX: e6f18014 ECX: c02604d5 EDX: e7173000
> ESI: e7173000 EDI: e7173000 EBP: e7851ca0 ESP: e7851c90
> DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
The problem is caused by:
commit b0ed43360f
Author: Hannes Reinecke <hare@suse.de>
Date: Tue Mar 18 14:32:28 2008 +0100
[SCSI] add scsi_host and scsi_target to scsi_bus
which added scsi_bus_type to the struct scsi_target device. This
causes both the scsi_device and scsi_target to fire scsi_bus_uevents.
However, the actualy scsi_bus_uevent() call assumes blindly that it's
a struct scsi_device. Check for this and return immediately if it
isn't.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This patch adds release callback support, which is called when a bsg
device goes away. bsg_register_queue() takes a pointer to a callback
function. This feature is useful for stuff like sas_host that can't
use the release callback in struct device.
If a caller doesn't need bsg's release callback, it can call
bsg_register_queue() with NULL pointer (e.g. scsi devices can use
release callback in struct device so they don't need bsg's callback).
With this patch, bsg uses kref for refcounts on bsg devices instead of
get/put_device in fops->open/release. bsg calls put_device and the
caller's release callback (if it was registered) in kref_put's
release.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James 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: James Bottomley <James.Bottomley@HansenPartnership.com>
This patch removes the unused sysfs attibute overwriting logic for
the scsi host attibutes, and plugs them into the driver core default
attribute creation.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This patch implements scsi_host and scsi_target device types
and adds both to the scsi_bus.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: James 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: Tony Jones <tonyj@suse.de>
Signed-off-by: Kay 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: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit 4b6f5b3a99.
bsg takes a reference to the underlying generic device, so it's
impossible to unregister bsg in the device release routine.
Acked-by: FUJITA Tomonori <tomof@acm.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Delay bsg unregistration, because we want to wait until all the request/cmds
have released their reference.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
While trying to convert the SPI transport class to attribute groups, I
discovered that we don't actually have any transport configure points
for either the target or the host. This patch adds these missing
transport class triggers. The host one is simply done after the add,
the target one tries to be more clever and add it after devices may have
been placed on the target (so the device configure will have set up the
target parameters).
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
A recent bug report:
http://bugzilla.kernel.org/show_bug.cgi?id=9674
Was caused because the ULDs now set their own prep functions, but
don't necessarily reset the prep function back to the SCSI default
when they are removed. This leads to panics if commands are sent to
the device after the module is removed because the prep_fn is still
pointing to the old module code. The fix for this is to implement a
bus remove method that resets the prep_fn pointer correctly before
calling the ULD specific driver remove method.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
if shost->supported mode is zero (i.e. MODE_UNKNOWN) show it as
initiator (it's obviously an unconverted driver that won't do target).
Acked-by: FUJITA Tomonori <tomof@acm.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.
Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This removes the unused sysfs attribute overwriting logic for most of
the attributes, and plugs them into the driver core default attribute
creation.
Without this patch, at the time of the events for the SCSI LUN's, there
will be no sysfs files, because their creation is delayed until the sd
driver has spun up the disks, which might take several seconds. It is the
last WAIT_FOR_SYSFS rule in the default udev setup which can be removed
with this change.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This adds supported_mode and active_mode attributes to
/sys/class/sys_host/hostX/ for specifying the mode that a lld supports
and the currently activated mode. The output format is similar to fc
rport roles:
luce:/sys/class/scsi_host/host0$ cat supported_mode
Initiator
luce:/sys/class/scsi_host/host0$ cat active_mode
Initiator
The mode values uses bitmap since we would support dual-mode llds in
the future like this:
luce:/sys/class/scsi_host/host0$ cat supported_mode
Initiator, Target
The supported_mode attribute looks at a scsi_host_template and the
active_mode attribute looks at a scsi_host. We would add a hook to a
scsi_host_template to change the active_mode attribute
dynamically. But now there is no hook since no lld supports that
feature.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Currently, bsg doesn't make class backlinks (a process whereby you'd get
a link to bsg in the device directory in the same way you get one for
sg). This is because the bsg device is uninitialised, so the class
device has nothing it can attach to. The fix is to make the bsg device
point to the cdevice of the entity creating the bsg, necessitating
changing the bsg_register_queue() prototype into a form that takes the
generic device.
Acked-by: FUJITA Tomonori <tomof@acm.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch moves the bsg registration into SCSI so that bsg no longer
has a dependency on the scsi_interface_register API.
This can be viewed as a temporary expedient until we can get universal
bsg binding sorted out properly. Also use the sdev bus_id as the
generic bsg name (to avoid clashes with the queue name).
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch contains the following cleanups:
- make needlessly global functions static
- every file should #include the headers containing the prototypes for
it's global functions
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
With libata converted to use sdev->manage_start_stop for suspend and
resume, sht->suspend/resume() has no user left and low level
suspend/ressume should be taken care of by low level driver's
suspend/resume callbacks (e.g. PCI or PCMCIA driver callbacks). This
patch removes sht->suspend/resume() callbacks.
This change is suggested by Christoph Hellwig.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: James 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: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: James 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: Tejun Heo <htejun@gmail.com>
Rejections fixed and
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch (as868) adds a helper routine for device drivers that need
to set up a callback to perform some action in a different process's
context. This is intended for use by attribute methods that want to
unregister themselves or their parent device. Attribute method calls
are mutually exclusive with unregistration, so such actions cannot be
taken directly.
Two attribute methods are converted to use the new helper routine: one
for SCSI device deletion and one for System/390 ccwgroup devices.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch will affect the CDB in INQUIRY commands sent to LUNs above 0
when LUN-0 reports a scsi_level of 0; the LUN bits will no longer be set
in the second byte of the CDB. This is as it should be. Nevertheless,
it's possible that some wacky device might be adversely affected. I doubt
anyone will complain...
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.
For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.
To make this work, an extra flag is introduced into the management side of the
work_struct. This governs auto-release of the structure upon execution.
Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function. This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated.. This is a
problem if the auxiliary data is taken away (as done by the last patch).
However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems. But then the work function must itself release the
work_struct by calling work_release().
In most cases, automatic release is fine, so this is the default. Special
initiators exist for the non-auto-release case (ending in _NAR).
Signed-Off-By: David Howells <dhowells@redhat.com>
Debugging TCQ issues has shown me this is a very useful parameter to be
able to view. Add it to he host class parameters.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]) and remove
duplicates of the macro.
Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
At the moment libata doesn't pass pm_message_t down ata_device_suspend.
This causes drives to be powered down when we just want a freeze,
causing unnecessary wear and tear. This patch gets pm_message_t passed
down so that it can be used to determine whether to power down the
drive.
Signed-off-by: Nigel Cunningham <nigel@suspend2.net>
drivers/scsi/libata-core.c | 5 +++--
drivers/scsi/libata-scsi.c | 4 ++--
drivers/scsi/scsi_sysfs.c | 2 +-
include/linux/libata.h | 4 ++--
include/scsi/scsi_host.h | 2 +-
5 files changed, 9 insertions(+), 8 deletions(-)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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: James Bottomley <James.Bottomley@SteelEye.com>
There's a bug in releasing scsi_device where the release function
actually frees the block queue. However, the block queue release
calls flush_work(), which requires process context (the scsi_device
structure may release from irq context). Update the release function
to invoke via the execute_in_process_context() API.
Also clean up the scsi_target structure releasing via this API.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
When James Smart fixed the issue of the userspace scan atributes
crashing the system with the FC transport class he added a patch to
let the transport class check if the parent is valid for a given
transport class.
When adding support for the integrated raid of fusion sas devices
we ran into a problem with that, as it didn't allow adding virtual
raid volumes without the transport class knowing about it.
So this patch adds a user_scan attribute instead, that takes over from
scsi_scan_host_selected if the transport class sets it and thus lets
the transport class control the user-initiated scanning. As this
plugs the hole about user-initiated scanning the target_parent hook
goes away and we rely on callers of the scanning routines to do
something sensible.
For SAS this meant I had to switch from a spinlock to a mutex to
synchronize the topology linked lists, in FC they were completely
unsynchronized which seems wrong.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
the scsi layer is using semaphores in a mutex way, this patch converts
these into using mutexes instead
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch adds suspend patch to libata, and ata_piix in particular. For
most low level drivers, they should just need to add the 4 hooks to
work. As I can only test ata_piix, I didn't enable it for more
though.
Suspend support is the single most important feature on a notebook, and
most new notebooks have sata drives. It's quite embarrassing that we
_still_ do not support this. Right now, it's perfectly possible to
suspend the drive in mid-transfer.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
patch below marks a few scsi core datastructures as const, so that they end up
in the .rodata section and don't cacheline share with things that get dirtied
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
There's an oops that sometimes shows up with SCSI transport classes in
sysfs_hash_and_remove. The problem is that now, because of the class to
device and vice versa symlinks, all classes have to be removed from
visibility *before* the device is removed from visibility.
The transport class trigger points violate this, so bring them back into
conformance.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
We fix the oops by enforcing the host state model. There have also
been two extra states added: SHOST_CANCEL_RECOVERY and
SHOST_DEL_RECOVERY so we can take the model through host removal while
the recovery thread is active.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch (as545) fixes the list traversals in __scsi_remove_target and
scsi_forget_host. In each case the existing code list_for_each_entry_safe
in an _unsafe_ manner, because the list was not protected from outside
modification while the iteration was running.
The new scsi_forget_host routine takes the moderately controversial step
of iterating over devices for removal rather than iterating over targets.
This makes more sense to me because the current scheme treats targets as
second-class citizens, created and removed on demand, rather than as
objects corresponding to actual hardware. (Also I couldn't figure out any
safe way to iterate over the target list, since it's not so easy to tell
when a target has already been removed.)
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch (as544) adds a private entry point to scsi_remove_device, for
use when callers already own the scan_mutex. The appropriate callers are
modified to use the new entry point.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Migrate the current SCSI host state model to a model like SCSI
device is using.
Signed-off-by: Mike Anderson <andmike@us.ibm.com>
Rejections fixed up and
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Another rollup of patches which give various symbols static scope
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- add a comment to the device structure that the device_busy field
is now protected by the request_queue->queue_lock
- null out sdev->request_queue after the queue is released to trap
any (and there shouldn't be any) use after the queue is freed.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Chandra Seetharaman