Use a generic wait_queue to prevent the wait_queue in dasd_sleep_on_
functions from being referenced by callback_data while it does not
exist any more.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When the dasd_int_handler is called with an error code instead of
an irb, the associated request should be restarted. This handling
was missing from the -ETIMEDOUT case. In fact it should be done in
any case.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We should use 'const char *' in the busid functions since the
strings are not modified anyway.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove proc_root export. Creation and removal works well if parent PDE is
supplied as NULL -- it worked always that way.
So, one useless export removed and consistency added, some drivers created
PDEs with &proc_root as parent but removed them as NULL and so on.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alter the block device ->direct_access() API to work with the new
get_xip_mem() API (that requires both kaddr and pfn are returned).
Some architectures will not do the right thing in their virt_to_page() for use
by XIP (to translate from the kernel virtual address returned by
direct_access(), to a user mappable pfn in XIP's page fault handler.
However, we can't switch it to just return the pfn and not the kaddr, because
we have no good way to get a kva from a pfn, and XIP requires the kva for its
read(2) and write(2) handlers. So we have to return both.
Signed-off-by: Jared Hulbert <jaredeh@gmail.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-mm@kvack.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the function that prints the segment warning messages found in the
monreader driver and the dcssblk driver to the extmem base code.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Most noteable part of this commit is the new local header file entry.h
which contains all the function declarations of functions that get only
called from asm code or are arch internal. That way we can avoid extern
declarations in C files.
This is more or less the same that was done for sparc64.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Now the system reports system information messages (SIM) to the user.
The System Reference Code (SRC) which is reported to the user gives
the abbility to lookup the reason of the SIM online in the
documentation of the storage server.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
I compiled the kernel without deadline, and the dasd code exits the old
scheduler (CFQ), fails to load the new one (deadline), and then things just
hang - with one of these (sorry about the weird chars - I copy & pasted it
from a 3270 console):
dasd(eckd): 0.0.0151: 3390/0A(CU:3990/01) Cyl:3338 Head:15 Sec:224
------------ cut here ------------
Badness at kernel/mutex.c:134
Modules linked in: dasd_eckd_mod dasd_mod
CPU: 0 Not tainted 2.6.25-rc3 #9
Process exe (pid: 538, task: 000000000d172000, ksp: 000000000d21ef88)
Krnl PSW : 0404000180000000 000000000022fb5c (mutex_lock_nested+0x2a4/0x2cc)
R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:0 PM:0 EA:3
Krnl GPRS: 0000000000024218 000000000076fc78 0000000000000000 000000000000000f
000000000022f92e 0000000000449898 000000000f921c00 000003e000162590
00000000001539c4 000000000d172000 070000007fffffff 000000000d21f400
000000000f8f2560 00000000002413f8 000000000022fb44 000000000d21f400
Krnl Code: 000000000022fb50: bf2f1000 icm %r2,15,0(%r1)
000000000022fb54: a774fef6 brc 7,22f940
000000000022fb58: a7f40001 brc 15,22fb5a
>000000000022fb5c: a7f4fef2 brc 15,22f940
000000000022fb60: c0e5fffa112a brasl %r14,171db4
000000000022fb66: 1222 ltr %r2,%r2
000000000022fb68: a784fedb brc 8,22f91e
000000000022fb6c: c010002a0086 larl %r1,76fc78
Call Trace:
(<000000000022f92e> mutex_lock_nested+0x76/0x2cc)
<00000000001539c4> elevator_exit+0x38/0x80
<0000000000156ffe> blk_cleanup_queue+0x62/0x7c
<000003e0001d5414> dasd_change_state+0xe0/0x8ec
<000003e0001d5cae> dasd_set_target_state+0x8e/0x9c
<000003e0001d5f74> dasd_generic_set_online+0x160/0x284
<000003e00011e83a> dasd_eckd_set_online+0x2e/0x40
<0000000000199bf4> ccw_device_set_online+0x170/0x2c0
<0000000000199d9e> online_store_recog_and_online+0x5a/0x14c
<000000000019a08a> online_store+0xbe/0x2ec
<000000000018456c> dev_attr_store+0x38/0x58
<000000000010efbc> sysfs_write_file+0x130/0x190
<00000000000af582> vfs_write+0xb2/0x160
<00000000000afc7c> sys_write+0x54/0x9c
<0000000000025e16> sys32_write+0x2e/0x50
<0000000000024218> sysc_noemu+0x10/0x16
<0000000077e82bd2> 0x77e82bd2
Set elevator pointer to NULL in order to avoid double elevator_exit
calls when elevator_init call for deadline iosched fails.
Also make sure the dasd device driver depends on IOSCHED_DEADLINE so
the default IO scheduler of the dasd driver is present.
Signed-off-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Using the /proc/dasd/devices interface leaves the reference counter
of alias devices in an inconsistent state. A process that tries to set
such a device offline afterwards will hang.
The dasd_devices_show function returns immediately for alias devices
and this code path was missing a dasd_put_device call.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When a request fails that was started on an alias device then the
first recovery step is to retry it on the base device. If the
recovery request fails again with the same symptoms, the next step
should not be a simple retry, but should be a proper recovery based
on sense data, etc. To do so, the dasd recovery functions need to
recognize the alias recovery step in the erp chain by comparing
the start devices.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
After setting the status of the cqr and releasing the lock for the
block cqr queue, we call the cqr callback function, which will usually
just trigger the dasd_block_tasklet. But when the tasklet is already
running the cqr might be processed before we invoke the callback
function. In rare cases the callback pointer may already be invalid
by the time we want to call it, which will result in a panic.
Solution: Call the callback function first and then release the lock.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case a dcss segment cannot be loaded blk_cleanup_queue
will be called before blk_queue_make_request, leaving the
struct work unplug_work of the request queue uninitialized
before it is used.
That leads also to the lockdep message below.
To avoid that call blk_queue_make_request right after the
request_queue has been allocated.
This makes sure that the struct work is always initialized
before it is used.
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 2 Not tainted 2.6.24 #6
Process swapper (pid: 1, task: 000000000f854038, ksp: 000000000f85f980)
040000000f85f860 000000000f85f880 0000000000000002 0000000000000000
000000000f85f920 000000000f85f898 000000000f85f898 000000000001622e
0000000000000000 000000000f85f980 0000000000000000 0000000000000000
000000000f85f880 000000000000000c 000000000f85f880 000000000f85f8f0
0000000000342908 000000000001622e 000000000f85f880 000000000f85f8d0
Call Trace:
([<000000000001619e>] show_trace+0xda/0x104)
[<0000000000016288>] show_stack+0xc0/0xf8
[<00000000000163d0>] dump_stack+0xb0/0xc0
[<000000000006e4ea>] __lock_acquire+0x47e/0x1160
[<000000000006f27c>] lock_acquire+0xb0/0xd8
[<000000000005a522>] __cancel_work_timer+0x9e/0x240
[<000000000005a72e>] cancel_work_sync+0x2a/0x3c
[<0000000000165c46>] kblockd_flush_work+0x26/0x34
[<0000000000169034>] blk_sync_queue+0x38/0x48
[<0000000000169080>] blk_release_queue+0x3c/0xa8
[<000000000017bce8>] kobject_cleanup+0x58/0xac
[<000000000017bd66>] kobject_release+0x2a/0x38
[<000000000017d28e>] kref_put+0x6e/0x94
[<000000000017bc80>] kobject_put+0x38/0x48
[<00000000001653be>] blk_put_queue+0x2a/0x38
[<0000000000168fee>] blk_cleanup_queue+0x82/0x90
[<0000000000213e7e>] dcssblk_add_store+0x34e/0x700
[<00000000005243b8>] dcssblk_init+0x1a0/0x308
[<000000000050a3c2>] kernel_init+0x1b2/0x3a4
[<000000000001ac82>] kernel_thread_starter+0x6/0xc
[<000000000001ac7c>] kernel_thread_starter+0x0/0xc
INFO: lockdep is turned off.
Cc: Gerald Schaefer <geraldsc@de.ibm.com>
Cc: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When an alias device is set offline while it is in use this may
result in a panic in the cleanup part of the dasd_block_tasklet.
The problem here is that there may exist some ccw requests that were
originally created for the alias device and transferred to the base
device when the alias was set offline. When these request are
cleaned up later, the discipline pointer in the alias device may not
be valid anymore. To fix this use the base device discipline to find
the cleanup function.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Adding interface control check (ifcc) handling in error recovery.
First retry up to 255 times and if all retries fail try an alternate
path if possible.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add time to the 'expires' value to avoid a loop caused by the cqr
termination function
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Parallel access volumes (PAV) is a storage server feature, that allows
to start multiple channel programs on the same DASD in parallel. It
defines alias devices which can be used as alternative paths to the
same disk. With the old base PAV support we only needed rudimentary
functionality in the DASD device driver. As the mapping between base
and alias devices was static, we just had to export an identifier
(uid) and could leave the combining of devices to external layers
like a device mapper multipath.
Now hyper PAV removes the requirement to dedicate alias devices to
specific base devices. Instead each alias devices can be combined with
multiple base device on a per request basis. This requires full
support by the DASD device driver as now each channel program itself
has to identify the target base device.
The changes to the dasd device driver and the ECKD discipline are:
- Separate subchannel device representation (dasd_device) from block
device representation (dasd_block). Only base devices are block
devices.
- Gather information about base and alias devices and possible
combinations.
- For each request decide which dasd_device should be used (base or
alias) and build specific channel program.
- Support summary unit checks, which allow the storage server to
upgrade / downgrade between base and hyper PAV at runtime (support
is mandatory).
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
