linux.git/drivers/s390, branch v3.1-rc2

[S390] qdio: Use kstrtoul_from_user

2011-08-03T14:44:21+00:00

This patch replaces the code for getting an unsigned long from a
userspace buffer by a simple call to kstroul_from_user.
This makes it easier to read and less error prone.

Signed-off-by: Peter Huewe 
Acked-by: Jan Glauber 
Signed-off-by: Heiko Carstens

[S390] sclp_async: Use kstrtoul_from_user

2011-08-03T14:44:20+00:00

This patch replaces the code for getting an unsigned long from a
userspace buffer by a simple call to kstroul_from_user.
This makes it easier to read and less error prone.

Signed-off-by: Peter Huewe 
Signed-off-by: Heiko Carstens

[S390] dasd: check if raw track access is supported

2011-08-03T14:44:19+00:00

To use raw track access some special storage server commands are
needed. Older storage hardware may not support these commands.
So check if raw track access is possible while setting the DASD
online.

Signed-off-by: Stefan Haberland 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Heiko Carstens

[S390] dasd: use vmalloc for statistics input buffer

2011-08-03T14:44:19+00:00

The size of the buffer that is used to store DASD statistics input
strings depends on the user input. If the input string is to large,
the write operation could fail with -ENOMEM. To avoid this, use
vmalloc instead of kmalloc.

Signed-off-by: Stefan Weinhuber 
Signed-off-by: Heiko Carstens

[S390] qdio: 2nd stage retry on SIGA-W busy conditions

2011-08-03T14:44:19+00:00

The SIGA-W may return with the busy bit set which means the device was
blocked. The busy loop which retries the SIGA-W for 100us may not be
long enough when running under a heavily loaded hypervisor.

Extend the retry mechanism by adding a longer second stage which retries
the SIGA-W for up to 10s. In difference to the first retry loop the second
stage is using mdelay to stop the cpu between the retries and thereby
avoid additional preassure in on the hypervisor.
If the second stage retry is successfull a device reset is avoided.

Signed-off-by: Jan Glauber 
Signed-off-by: Heiko Carstens

atomic: use

2011-07-26T23:49:47+00:00

This allows us to move duplicated code in 
(atomic_inc_not_zero() for now) to 

Signed-off-by: Arun Sharma 
Reviewed-by: Eric Dumazet 
Cc: Ingo Molnar 
Cc: David Miller 
Cc: Eric Dumazet 
Acked-by: Mike Frysinger 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[S390] dasd: add enhanced DASD statistics interface

2011-07-24T08:48:23+00:00

This patch extends the DASD statistics to allow for a more detailed
analysis of DASD I/O operations. In particular we want the statistics
to provide answers to the following questions:
- How many requests used a PAV alias?
- How many requests used High Performance FICON?
- How do read request perform versus write requests?

The existing DASD statistics interface has several shortcomings
- The interface for global data is a formatted text table in procfs
  (/proc/dasd/statistics). The layout is meant for human readers and
  is not to easy to parse. If values get to large for the table
  layout, they get scaled down.
- The statistics which are collected per block device can be
  accessed via an ioctl interface, which can only be extended by
  defining a new ioctl.
- There is no statistics interface for individual PAV base and alias
  devices.

To overcome theses shortcomings we create a new DASD statistics
interface in debugfs. This interface will contain one entry for global
data, one per DASD block device, and one per DASD base and alias
device. Each file contains the statistic data in easy to parse
name/value and name/array pairs. The existing interfaces will remain
functional, but they will not be extended.

Signed-off-by: Stefan Weinhuber 
Signed-off-by: Martin Schwidefsky

[S390] ap: toleration support for ap device type 10

2011-07-24T08:48:22+00:00

Add toleration support for ap devices with device type 10.

Signed-off-by: Holger Dengler 
Signed-off-by: Martin Schwidefsky

[S390] qdio: clear shared DSCI before scheduling the queue handler

2011-07-24T08:48:00+00:00

The following race can occur with qdio devices that use the shared device
state change indicator:

Device (Shared DSCI)    CPU0                            CPU1
===============================================================================

1. DSCI 0 => 1,
   INT pending
                        2. Thinint handler
                        * si_used = 1
                        * Inbound tasklet_schedule
                        * DSCI 1 => 0

3. DSCI 0 => 1,
   INT pending

                                                        4. Thinint handler
                                                        * si_used = 1
                                                        * Inbound tasklet_schedu
le
                                                           => NOP

                        5. Inbound tasklet run

6. DSCI = 1,
   INT surpressed

                                                        7. DSCI 1 => 0

The race would lead to a stall where new data in the input queue is
not recognized so the device stops working in case of no further traffic.

Fix the race by resetting the DSCI before scheduling the inbound tasklet
so the device generates an interrupt if new data arrives in the above
scenario in step 6.

Reviewed-by: Ursula Braun 
Signed-off-by: Jan Glauber 
Signed-off-by: Martin Schwidefsky

[S390] kconfig: remove tape interface support comment

2011-07-24T08:48:00+00:00

There is nothing below the menu entry "S/390 tape interface support".
Remove it.

Signed-off-by: Martin Schwidefsky