scsi: ses: Have midlayer retry scsi_execute_cmd() errors

This has ses have the SCSI midlayer retry scsi_execute_cmd() errors instead
of driving them itself.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20240123002220.129141-17-michael.christie@oracle.com
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

driver core: class: remove struct class_interface * from callbacks

The add_dev and remove_dev callbacks in struct class_interface currently
pass in a pointer back to the class_interface structure that is calling
them, but none of the callback implementations actually use this pointer
as it is pointless (the structure is known, the driver passed it in in
the first place if it is really needed again.)

So clean this up and just remove the pointer from the callbacks and fix
up all callback functions.

Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Allen Hubbe <allenbh@gmail.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: John Stultz <jstultz@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Wang Weiyang <wangweiyang2@huawei.com>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Cc: Jakob Koschel <jakobkoschel@gmail.com>
Cc: Cai Xinchen <caixinchen1@huawei.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://lore.kernel.org/r/2023040250-pushover-platter-509c@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: ses: Handle enclosure with just a primary component gracefully

This reverts commit 3fe97ff3d949 ("scsi: ses: Don't attach if enclosure
has no components") and introduces proper handling of case where there are
no detected secondary components, but primary component (enumerated in
num_enclosures) does exist. That fix was originally proposed by Ding Hui
<dinghui@sangfor.com.cn>.

Completely ignoring devices that have one primary enclosure and no
secondary one results in ses_intf_add() bailing completely

scsi 2:0:0:254: enclosure has no enumerated components
scsi 2:0:0:254: Failed to bind enclosure -12ven in valid configurations such

even on valid configurations with 1 primary and 0 secondary enclosures as
below:

# sg_ses /dev/sg0
3PARdata SES 3321
Supported diagnostic pages:
Supported Diagnostic Pages [sdp] [0x0]
Configuration (SES) [cf] [0x1]
Short Enclosure Status (SES) [ses] [0x8]
# sg_ses -p cf /dev/sg0
3PARdata SES 3321
Configuration diagnostic page:
number of secondary subenclosures: 0
generation code: 0x0
enclosure descriptor list
Subenclosure identifier: 0 [primary]
relative ES process id: 0, number of ES processes: 1
number of type descriptor headers: 1
enclosure logical identifier (hex): 20000002ac02068d
enclosure vendor: 3PARdata product: VV rev: 3321
type descriptor header and text list
Element type: Unspecified, subenclosure id: 0
number of possible elements: 1

The changelog for the original fix follows

=====
We can get a crash when disconnecting the iSCSI session,
the call trace like this:

[ffff00002a00fb70] kfree at ffff00000830e224
[ffff00002a00fba0] ses_intf_remove at ffff000001f200e4
[ffff00002a00fbd0] device_del at ffff0000086b6a98
[ffff00002a00fc50] device_unregister at ffff0000086b6d58
[ffff00002a00fc70] __scsi_remove_device at ffff00000870608c
[ffff00002a00fca0] scsi_remove_device at ffff000008706134
[ffff00002a00fcc0] __scsi_remove_target at ffff0000087062e4
[ffff00002a00fd10] scsi_remove_target at ffff0000087064c0
[ffff00002a00fd70] __iscsi_unbind_session at ffff000001c872c4
[ffff00002a00fdb0] process_one_work at ffff00000810f35c
[ffff00002a00fe00] worker_thread at ffff00000810f648
[ffff00002a00fe70] kthread at ffff000008116e98

In ses_intf_add, components count could be 0, and kcalloc 0 size scomp,
but not saved in edev->component[i].scratch

In this situation, edev->component[0].scratch is an invalid pointer,
when kfree it in ses_intf_remove_enclosure, a crash like above would happen
The call trace also could be other random cases when kfree cannot catch
the invalid pointer

We should not use edev->component[] array when the components count is 0
We also need check index when use edev->component[] array in
ses_enclosure_data_process
=====

Reported-by: Michal Kolar <mich.k@seznam.cz>
Originally-by: Ding Hui <dinghui@sangfor.com.cn>
Cc: stable@vger.kernel.org
Fixes: 3fe97ff3d949 ("scsi: ses: Don't attach if enclosure has no components")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Link: https://lore.kernel.org/r/nycvar.YFH.7.76.2304042122270.29760@cbobk.fhfr.pm
Tested-by: Michal Kolar <mich.k@seznam.cz>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Don't attach if enclosure has no components

An enclosure with no components can't usefully be operated by the driver
(since effectively it has nothing to manage), so report the problem and
don't attach. Not attaching also fixes an oops which could occur if the
driver tries to manage a zero component enclosure.

[mkp: Switched to KERN_WARNING since this scenario is common]

Link: https://lore.kernel.org/r/c5deac044ac409e32d9ad9968ce0dcbc996bfc7a.camel@linux.ibm.com
Cc: stable@vger.kernel.org
Reported-by: Ding Hui <dinghui@sangfor.com.cn>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fix slab-out-of-bounds in ses_intf_remove()

A fix for:

BUG: KASAN: slab-out-of-bounds in ses_intf_remove+0x23f/0x270 [ses]
Read of size 8 at addr ffff88a10d32e5d8 by task rmmod/12013

When edev->components is zero, accessing edev->component[0] members is
wrong.

Link: https://lore.kernel.org/r/20230202162451.15346-5-thenzl@redhat.com
Cc: stable@vger.kernel.org
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fix possible desc_ptr out-of-bounds accesses

Sanitize possible desc_ptr out-of-bounds accesses in
ses_enclosure_data_process().

Link: https://lore.kernel.org/r/20230202162451.15346-4-thenzl@redhat.com
Cc: stable@vger.kernel.org
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fix possible addl_desc_ptr out-of-bounds accesses

Sanitize possible addl_desc_ptr out-of-bounds accesses in
ses_enclosure_data_process().

Link: https://lore.kernel.org/r/20230202162451.15346-3-thenzl@redhat.com
Cc: stable@vger.kernel.org
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fix slab-out-of-bounds in ses_enclosure_data_process()

A fix for:

BUG: KASAN: slab-out-of-bounds in ses_enclosure_data_process+0x949/0xe30 [ses]
Read of size 1 at addr ffff88a1b043a451 by task systemd-udevd/3271

Checking after (and before in next loop) addl_desc_ptr[1] is sufficient, we
expect the size to be sanitized before first access to addl_desc_ptr[1].
Make sure we don't walk beyond end of page.

Link: https://lore.kernel.org/r/20230202162451.15346-2-thenzl@redhat.com
Cc: stable@vger.kernel.org
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Convert to scsi_execute_cmd()

scsi_execute_req() is going to be removed. Convert ses to
scsi_execute_cmd().

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fix unsigned comparison with less than zero

Fix the following coccicheck warning:

./drivers/scsi/ses.c:137:10-16: WARNING: Unsigned expression compared
with zero: result > 0.

Link: https://lore.kernel.org/r/1632477113-90378-1-git-send-email-jiapeng.chong@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Retry failed Send/Receive Diagnostic commands

Setting SCSI logging level with error=3, we saw some errors from enclosues:

[108017.360833] ses 0:0:9:0: tag#641 Done: NEEDS_RETRY Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK cmd_age=0s
[108017.360838] ses 0:0:9:0: tag#641 CDB: Receive Diagnostic 1c 01 01 00 20 00
[108017.427778] ses 0:0:9:0: Power-on or device reset occurred
[108017.427784] ses 0:0:9:0: tag#641 Done: SUCCESS Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
[108017.427788] ses 0:0:9:0: tag#641 CDB: Receive Diagnostic 1c 01 01 00 20 00
[108017.427791] ses 0:0:9:0: tag#641 Sense Key : Unit Attention [current]
[108017.427793] ses 0:0:9:0: tag#641 Add. Sense: Bus device reset function occurred
[108017.427801] ses 0:0:9:0: Failed to get diagnostic page 0x1
[108017.427804] ses 0:0:9:0: Failed to bind enclosure -19
[108017.427895] ses 0:0:10:0: Attached Enclosure device
[108017.427942] ses 0:0:10:0: Attached scsi generic sg18 type 13

Retry if the Send/Receive Diagnostic commands complete with a transient
error status (NOT_READY or UNIT_ATTENTION with ASC 0x29).

Link: https://lore.kernel.org/r/1631849061-10210-2-git-send-email-wenxiong@linux.ibm.com
Reviewed-by: Brian King <brking@linux.ibm.com>
Reviewed-by: James Bottomley <jejb@linux.ibm.com>
Signed-off-by: Wen Xiong <wenxiong@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 176

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 675 mass ave cambridge ma 02139 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 44 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170025.980374610@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: ses: switch to SPDX tags

Use the the GPLv2 SPDX tag instead of verbose boilerplate text.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

treewide: kzalloc() -> kcalloc()

The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

kzalloc(a * b, gfp)

with:
kcalloc(a * b, gfp)

as well as handling cases of:

kzalloc(a * b * c, gfp)

with:

kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
kzalloc(
- (sizeof(TYPE)) * E
+ sizeof(TYPE) * E
, ...)
|
kzalloc(
- (sizeof(THING)) * E
+ sizeof(THING) * E
, ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
kzalloc(
- sizeof(u8) * (COUNT)
+ COUNT
, ...)
|
kzalloc(
- sizeof(__u8) * (COUNT)
+ COUNT
, ...)
|
kzalloc(
- sizeof(char) * (COUNT)
+ COUNT
, ...)
|
kzalloc(
- sizeof(unsigned char) * (COUNT)
+ COUNT
, ...)
|
kzalloc(
- sizeof(u8) * COUNT
+ COUNT
, ...)
|
kzalloc(
- sizeof(__u8) * COUNT
+ COUNT
, ...)
|
kzalloc(
- sizeof(char) * COUNT
+ COUNT
, ...)
|
kzalloc(
- sizeof(unsigned char) * COUNT
+ COUNT
, ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * (COUNT_ID)
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * COUNT_ID
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * (COUNT_CONST)
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * COUNT_CONST
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * (COUNT_ID)
+ COUNT_ID, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * COUNT_ID
+ COUNT_ID, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * (COUNT_CONST)
+ COUNT_CONST, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * COUNT_CONST
+ COUNT_CONST, sizeof(THING)
, ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
(
- SIZE * COUNT
+ COUNT, SIZE
, ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
kzalloc(
- sizeof(TYPE) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
kzalloc(
- sizeof(TYPE) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
kzalloc(
- sizeof(TYPE) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
kzalloc(
- sizeof(TYPE) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
kzalloc(
- sizeof(THING) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
kzalloc(
- sizeof(THING) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
kzalloc(
- sizeof(THING) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
kzalloc(
- sizeof(THING) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
kzalloc(
- sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
kzalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
kzalloc(
- sizeof(THING1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
kzalloc(
- sizeof(THING1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
kzalloc(
- sizeof(TYPE1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
|
kzalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
kzalloc(
- (COUNT) * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- COUNT * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- COUNT * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- (COUNT) * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- COUNT * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- (COUNT) * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- (COUNT) * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
kzalloc(
- COUNT * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
kzalloc(C1 * C2 * C3, ...)
|
kzalloc(
- (E1) * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
|
kzalloc(
- (E1) * (E2) * E3
+ array3_size(E1, E2, E3)
, ...)
|
kzalloc(
- (E1) * (E2) * (E3)
+ array3_size(E1, E2, E3)
, ...)
|
kzalloc(
- E1 * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
kzalloc(sizeof(THING) * C2, ...)
|
kzalloc(sizeof(TYPE) * C2, ...)
|
kzalloc(C1 * C2 * C3, ...)
|
kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * (E2)
+ E2, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(TYPE) * E2
+ E2, sizeof(TYPE)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * (E2)
+ E2, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- sizeof(THING) * E2
+ E2, sizeof(THING)
, ...)
|
- kzalloc
+ kcalloc
(
- (E1) * E2
+ E1, E2
, ...)
|
- kzalloc
+ kcalloc
(
- (E1) * (E2)
+ E1, E2
, ...)
|
- kzalloc
+ kcalloc
(
- E1 * E2
+ E1, E2
, ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>

scsi: ses: don't ask for diagnostic pages repeatedly during probe

We are testing if there is a match with the ses device in a loop by
calling ses_match_to_enclosure(), which will issue scsi receive
diagnostics commands to the ses device for every device on the same
host. On one of our boxes with 840 disks, it takes a long time to load
the driver:

[root@g1b-oss06 ~]# time modprobe ses

real 40m48.247s
user 0m0.001s
sys 0m0.196s

With the patch:

[root@g1b-oss06 ~]# time modprobe ses

real 0m17.915s
user 0m0.008s
sys 0m0.053s

Note that we still need to refresh page 10 when we see a new disk to
create the link.

Signed-off-by: Li Dongyang <dongyang.li@anu.edu.au>
Tested-by: Jason Ozolins <jason.ozolins@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fix racy cleanup of /sys in remove_dev()

Currently we free the resources backing the enclosure device before we
call device_unregister(). This is racy: during rmmod of low-level SCSI
drivers that hook into enclosure, we end up with a small window of time
during which writing to /sys can OOPS. Example trace with mpt3sas:

general protection fault: 0000 [#1] SMP KASAN
Modules linked in: mpt3sas(-) <...>
RIP: [<ffffffffa0388a98>] ses_get_page2_descriptor.isra.6+0x38/0x220 [ses]
Call Trace:
[<ffffffffa0389d14>] ses_set_fault+0xf4/0x400 [ses]
[<ffffffffa0361069>] set_component_fault+0xa9/0xf0 [enclosure]
[<ffffffff8205bffc>] dev_attr_store+0x3c/0x70
[<ffffffff81677df5>] sysfs_kf_write+0x115/0x180
[<ffffffff81675725>] kernfs_fop_write+0x275/0x3a0
[<ffffffff8151f810>] __vfs_write+0xe0/0x3e0
[<ffffffff8152281f>] vfs_write+0x13f/0x4a0
[<ffffffff81526731>] SyS_write+0x111/0x230
[<ffffffff828b401b>] entry_SYSCALL_64_fastpath+0x13/0x94

Fortunately the solution is extremely simple: call device_unregister()
before we free the resources, and the race no longer exists. The driver
core holds a reference over ->remove_dev(), so AFAICT this is safe.

Signed-off-by: Calvin Owens <calvinowens@fb.com>
Acked-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: make page2 support optional

Simple subenclosures do not need to support SES page 2, so make it
optional.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fixup error message 'failed to get diagnostic page 0xffffffea'

The printk was using the result as argument, leading to a slightly
confusing log message.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: check return code from ses_recv_diag()

We should be checking the return code from ses_recv_diag() to avoid
accessing invalid data.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fix wrong page error

If a SES device returns an error on a requested diagnostic page, we are
currently printing an error indicating the wrong page was received. Fix
this up to simply return a failure and only check the returned page when
the diagnostic page buffer was populated by the device.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: don't get power status of SES device slot on probe

The commit 08024885a2a3 ("ses: Add power_status to SES device slot")
introduced the 'power_status' attribute to enclosure components and
the associated callbacks.

There are 2 callbacks available to get the power status of a device:
1) ses_get_power_status() for 'struct enclosure_component_callbacks'
2) get_component_power_status() for the sysfs device attribute
(these are available for kernel-space and user-space, respectively.)

However, despite both methods being available to get power status
on demand, that commit also introduced a call to get power status
in ses_enclosure_data_process().

This dramatically increased the total probe time for SCSI devices
on larger configurations, because ses_enclosure_data_process() is
called several times during the SCSI devices probe and loops over
the component devices (but that is another problem, another patch).

That results in a tremendous continuous hammering of SCSI Receive
Diagnostics commands to the enclosure-services device, which does
delay the total probe time for the SCSI devices __significantly__:

Originally, ~34 minutes on a system attached to ~170 disks:

[ 9214.490703] mpt3sas version 13.100.00.00 loaded
...
[11256.580231] scsi 17:0:177:0: qdepth(16), tagged(1), simple(0),
ordered(0), scsi_level(6), cmd_que(1)

With this patch, it decreased to ~2.5 minutes -- a 13.6x faster

[ 1002.992533] mpt3sas version 13.100.00.00 loaded
...
[ 1151.978831] scsi 11:0:177:0: qdepth(16), tagged(1), simple(0),
ordered(0), scsi_level(6), cmd_que(1)

Back to the commit discussion.. on the ses_get_power_status() call
introduced in ses_enclosure_data_process(): impact of removing it.

That may possibly be in place to initialize the power status value
on device probe. However, those 2 functions available to retrieve
that value _do_ automatically refresh/update it. So the potential
benefit would be a direct access of the 'power_status' field which
does not use the callbacks...

But the only reader of 'struct enclosure_component::power_status'
is the get_component_power_status() callback for sysfs attribute,
and it _does_ check for and call the .get_power_status callback,
(which indeed is defined and implemented by that commit), so the
power status value is, again, automatically updated.

So, the remaining potential for a direct/non-callback access to
the power_status attribute would be out-of-tree modules -- well,
for those, if they are for whatever reason interested in values
that are set during device probe and not up-to-date by the time
they need it.. well, that would be curious.

Well, to handle that more properly, set the initial power state
value to '-1' (i.e., uninitialized) instead of '1' (power 'on'),
and check for it in that callback which may do an direct access
to the field value _if_ a callback function is not defined.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Fixes: 08024885a2a3 ("ses: Add power_status to SES device slot")
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: Fix SAS device detection in enclosure

The call to scsi_is_sas_rphy() needs to be made on the SAS end_device,
not on the SCSI device.

Fixes: 835831c57e9b ("ses: use scsi_is_sas_rphy instead of is_sas_attached")
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ses: use scsi_is_sas_rphy instead of is_sas_attached

Use scsi_is_sas_rphy() instead of is_sas_attached() to decide whether we
should obtain the SAS address from a scsi device or not. This will
prevent us from tripping on the BUG_ON() in sas_sdev_to_rdev() if the
rphy isn't attached to the SAS transport class, like it is with hpsa's
logical devices.

Fixes: 3f8d6f2a0 ('ses: fix discovery of SATA devices in SAS enclosures')
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

ses: Fix racy cleanup of /sys in remove_dev()

Currently we free the resources backing the enclosure device before we
call device_unregister(). This is racy: during rmmod of low-level SCSI
drivers that hook into enclosure, we end up with a small window of time
during which writing to /sys can OOPS. Example trace with mpt3sas:

general protection fault: 0000 [#1] SMP KASAN
Modules linked in: mpt3sas(-) <...>
RIP: [<ffffffffa0388a98>] ses_get_page2_descriptor.isra.6+0x38/0x220 [ses]
Call Trace:
[<ffffffffa0389d14>] ses_set_fault+0xf4/0x400 [ses]
[<ffffffffa0361069>] set_component_fault+0xa9/0xf0 [enclosure]
[<ffffffff8205bffc>] dev_attr_store+0x3c/0x70
[<ffffffff81677df5>] sysfs_kf_write+0x115/0x180
[<ffffffff81675725>] kernfs_fop_write+0x275/0x3a0
[<ffffffff8151f810>] __vfs_write+0xe0/0x3e0
[<ffffffff8152281f>] vfs_write+0x13f/0x4a0
[<ffffffff81526731>] SyS_write+0x111/0x230
[<ffffffff828b401b>] entry_SYSCALL_64_fastpath+0x13/0x94

Fortunately the solution is extremely simple: call device_unregister()
before we free the resources, and the race no longer exists. The driver
core holds a reference over ->remove_dev(), so AFAICT this is safe.

Signed-off-by: Calvin Owens <calvinowens@fb.com>
Reviewed-by: James Bottomley <jejb@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

ses: fix discovery of SATA devices in SAS enclosures

The current discovery routines use the VPD 0x83 inquiry page to find
the device SAS address and match it to the end point in the enclosure.
This doesn't work for SATA devices because expanders (or hosts) simply
make up an endpoint address for STP and thus the address returned by
the VPD page never matches. Instead of doing this, for SAS attached
devices, match by the direct endpoint address instead.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

ses: fix additional element traversal bug

KASAN found that our additional element processing scripts drop off
the end of the VPD page into unallocated space. The reason is that
not every element has additional information but our traversal
routines think they do, leading to them expecting far more additional
information than is present. Fix this by adding a gate to the
traversal routine so that it only processes elements that are expected
to have additional information (list is in SES-2 section 6.1.13.1:
Additional Element Status diagnostic page overview)

Reported-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Tested-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

ses: Fix problems with simple enclosures

Simple enclosure implementations (mostly USB) are allowed to return only
page 8 to every diagnostic query. That really confuses our
implementation because we assume the return is the page we asked for and
end up doing incorrect offsets based on bogus information leading to
accesses outside of allocated ranges. Fix that by checking the page
code of the return and giving an error if it isn't the one we asked for.
This should fix reported bugs with USB storage by simply refusing to
attach to enclosures that behave like this. It's also good defensive
practise now that we're starting to see more USB enclosures.

Reported-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Cc: stable@vger.kernel.org
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

scsi: rescan VPD attributes

The VPD page information might change, so we need to be able to update
it. This patch implements a VPD page rescan whenever the 'rescan' sysfs
attribute is triggered.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

ses: Add power_status to SES device slot

Add power_status to SES device slot, so we can power on/off the
HDDs behind the enclosure.

Check firmware status in ses_set_* before sending control pages to
firmware.

Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ses: add reliable slot attribute

The name provided by firmware is in a vendor specific format, publish
the slot number to have a reliable mechanism for identifying slots
across firmware implementations. If the enclosure does not provide a
slot number fallback to the component number which is guaranteed unique,
and usually mirrors the slot number.

Cleaned up the unused ses_component.desc in the process.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ses: add enclosure logical id

Export the NAA logical id for the enclosure. This is optionally
available from the sas_transport_class, but it is really a property of
the enclosure.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ses: generate KOBJ_CHANGE on enclosure attach

In support of a /dev/disk/by-slot populated with data from the enclosure
and ses modules udev needs notification when the new interface
files/links are available. Otherwise, any udev rules specified for the
disk cannot assume that the enclosure topology has settled.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ses: close potential registration race

The slot and address fields have a small window of instability when
userspace can read them before initialization. Separate
enclosure_component
allocation from registration.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

scsi: remove scsi_driver owner field

The driver core driver structure has grown an owner field and now
requires it to be set for all modular drivers. Set it up for
all scsi_driver instances and get rid of the now superflous
scsi_driver owner field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Shane M Seymour <shane.seymour@hp.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com
Reviewed-by: Hannes Reinecke <hare@suse.de>

[SCSI] ses: Use vpd information from scsi_device

The scsi_device now has VPD page83 information attached, so
there is no need to query it again.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] ses: requesting a fault indication

Noticed that when the sysfs interface of the SCSI SES
driver was used to request a fault indication the LED
flashed but the buzzer didn't sound. So it was doing
what REQUEST IDENT (locate) should do.

Changelog:
- fix the setting of REQUEST FAULT for the device slot
and array device slot elements in the enclosure control
diagnostic page
- note the potentially defective code that reads the
FAULT SENSED and FAULT REQUESTED bits from the enclosure
status diagnostic page

The attached patch is against git/scsi-misc-2.6

Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] ses: add subenclosure support

There have been many complaints that an enclosure with subenclosures
isn't attached to by the ses driver. Until now, though, no-one had
been willing to provide access to one.

Subenclosures are added simply by flattening the tree (i.e. all
subenclosure devices show up under the one main device). This may have
consequences if the naming is only unique per subenclosure, but that's a
bug for another day. The tested array had no page 7, so no device
naming at all. It also only had the disk devices on one of its
subenclosures (all the others had power, fans, temperature and various
sensors), so testing of this is fairly rudimentary.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] ses: show devices for enclosures with no page 7

enclosure page 7 gives us the "pretty" names of the enclosure slots.
Without a page 7, we can still use the enclosure code as long as we
make up numeric names for the slots. Unfortunately, the current code
fails to add any devices because the check for page 10 is in the wrong
place if we have no page 7. Fix it so that devices show up even if
the enclosure has no page 7.

Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

drivers/scsi/ses.c: eliminate double free

The few lines below the kfree of hdr_buf may go to the label err_free
which will also free hdr_buf. The most straightforward solution seems to
be to just move the kfree of hdr_buf after these gotos.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r@
identifier E;
expression E1;
iterator I;
statement S;
@@

*kfree(E);
... when != E = E1
when != I(E,...) S
when != &E
*kfree(E);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[SCSI] eliminate potential kmalloc failure in scsi_get_vpd_page()

The best way to fix this is to eliminate the intenal kmalloc() and
make the caller allocate the required amount of storage.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] ses: update enclosure data on hot add

Now that hot add works correctly, if a new device is added, we're still
operating on stale enclosure data, so fix that by updating the enclosure
diagnostic pages when we get notified of a device hot add

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] ses: add support for enclosure component hot removal

Right at the moment, hot removal of a device within an enclosure does
nothing (because the intf_remove only copes with enclosure removal not
with component removal). Fix this by adding a function to remove the
component. Also needed to fix the prototype of
enclosure_remove_device, since we know the device we've removed but
not the internal component number

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] ses: fix hotplug with multiple devices and expanders

In a situation either with expanders or with multiple enclosure
devices, hot add doesn't always work. This is because we try to find
a single enclosure device attached to the host. Fix this by looping
over all enclosure devices attached to the host and also by making the
find loop recognise that the enclosure devices may be expander remote
(i.e. not parented by the host).

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] ses: #if 0 the unused ses_match_host()

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] ses: code_set == 1 is tested twice

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] ses: Use new scsi VPD helper

SES had its own code to retrieve VPD from devices; convert it to use the
new scsi_get_vpd_page helper.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] struct device - replace bus_id with dev_name(), dev_set_name()

[jejb: limit ioctl to returning 20 characters to avoid overrun
on long device names and add a few more conversions]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] add residual argument to scsi_execute and scsi_execute_req

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: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] ses: fix VPD inquiry overrun

There are a few kerneloops.org reports like this one:

http://www.kerneloops.org/search.php?search=ses_match_to_enclosure

That seem to imply we're running off the end of the VPD inquiry data
(although at 512 bytes, it should be long enough for just about
anything). we should be using correctly sized buffers anyway, so put
those in and hope this oops goes away.

Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] ses: Fix timeout

Timeouts are measured in jiffies, not in seconds.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

SCSI: convert struct class_device to struct device

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>

[SCSI] ses: fix data corruption

one system: initrd get courrupted:

RAMDISK: Compressed image found at block 0
RAMDISK: incomplete write (-28 != 2048) 134217728
crc error
VFS: Mounted root (ext2 filesystem).
Freeing unused kernel memory: 388k freed
init_special_inode: bogus i_mode (177777)
Warning: unable to open an initial console.
init_special_inode: bogus i_mode (177777)
init_special_inode: bogus i_mode (177777)
Kernel panic - not syncing: No init found. Try passing init= option to kernel.

bisected to
commit 9927c68864e9c39cc317b4f559309ba29e642168
Author: James Bottomley <James.Bottomley@HansenPartnership.com>
Date: Sun Feb 3 15:48:56 2008 -0600

[SCSI] ses: add new Enclosure ULD

changes:
1. change char to unsigned char to avoid type change later.
2. preserve len for page1
3. need to move desc_ptr even the entry is not enclosure_component_device/raid.
so keep desc_ptr on right position
4. record page7 len, and double check if desc_ptr out of boundary before touch.
5. fix typo in subenclosure checking: should use hdr_buf instead.

[jejb: style fixes]

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] ses: fix memory leaks

fix leaking with scomp leaking when failing. Also free page10 on
driver removal and remove one extra space.

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] ses: add new Enclosure ULD

This adds support to SCSI for enclosure services devices. It also makes
use of the enclosure services added in an earlier patch to display the
enclosure topology in sysfs.

At the moment, the enclosures are SAS specific, but if anyone actually
has a non-SAS enclosure that follows the SES-2 standard, we can add that
as well.

On my Vitesse based system, the enclosures show up like this:

sparkweed:~# ls -l /sys/class/enclosure/0\:0\:1\:0/
total 0
-r--r--r-- 1 root root 4096 2008-02-03 15:44 components
lrwxrwxrwx 1 root root 0 2008-02-03 15:44 device -> ../../../devices/pci0000:01/0000:01:02.0/host0/port-0:0/expander-0:0/port-0:0:12/end_device-0:0:12/target0:0:1/0:0:1:0
drwxr-xr-x 2 root root 0 2008-02-03 15:44 SLOT 000
drwxr-xr-x 2 root root 0 2008-02-03 15:44 SLOT 001
drwxr-xr-x 2 root root 0 2008-02-03 15:44 SLOT 002
drwxr-xr-x 2 root root 0 2008-02-03 15:44 SLOT 003
drwxr-xr-x 2 root root 0 2008-02-03 15:44 SLOT 004
drwxr-xr-x 2 root root 0 2008-02-03 15:44 SLOT 005
lrwxrwxrwx 1 root root 0 2008-02-03 15:44 subsystem -> ../../enclosure
--w------- 1 root root 4096 2008-02-03 15:44 uevent

And the individual occupied slots like this:

sparkweed:~# ls -l /sys/class/enclosure/0\:0\:1\:0/SLOT\ 001/
total 0
-rw-r--r-- 1 root root 4096 2008-02-03 15:45 active
lrwxrwxrwx 1 root root 0 2008-02-03 15:45 device -> ../../../../devices/pci0000:01/0000:01:02.0/host0/port-0:0/expander-0:0/port-0:0:11/end_device-0:0:11/target0:0:0/0:0:0:0
-rw-r--r-- 1 root root 4096 2008-02-03 15:45 fault
-rw-r--r-- 1 root root 4096 2008-02-03 15:45 locate
-rw-r--r-- 1 root root 4096 2008-02-03 15:45 status
lrwxrwxrwx 1 root root 0 2008-02-03 15:45 subsystem -> ../../../enclosure_component
-r--r--r-- 1 root root 4096 2008-02-03 15:45 type
--w------- 1 root root 4096 2008-02-03 15:45 uevent

You can flash the various blinky lights by echoing to the fault and locate files.

>From the device's point of view, you can see it has an enclosure like this:

sparkweed:~# ls /sys/class/scsi_disk/0\:0\:0\:0/device/
block:sda generic queue_depth state
bsg:0:0:0:0 iocounterbits queue_type subsystem
bus iodone_cnt rescan timeout
delete ioerr_cnt rev type
device_blocked iorequest_cnt scsi_device:0:0:0:0 uevent
driver modalias scsi_disk:0:0:0:0 vendor
enclosure_component:SLOT 001 model scsi_generic:sg0
evt_media_change power scsi_level

Note the enclosure_component:SLOT 001 which shows where in the enclosure
this device fits.

The astute will notice that I'm using SCSI VPD Inquiries to identify the
devices. This, unfortunately, won't work for SATA devices unless we do
some really nasty hacking about on the SAT because the only think that
knows the SAS addresses for SATA devices is libsas, not libata where the
SAT resides.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>