kernel.git/drivers/s390/cio, branch linux-3.12.y

s390/qdio: clear DSCI prior to scanning multiple input queues

2017-03-13T20:40:45Z

commit 1e4a382fdc0ba8d1a85b758c0811de3a3631085e upstream. For devices with multiple input queues, tiqdio_call_inq_handlers() iterates over all input queues and clears the device's DSCI during each iteration. If the DSCI is re-armed during one of the later iterations, we therefore do not scan the previous queues again. The re-arming also raises a new adapter interrupt. But its handler does not trigger a rescan for the device, as the DSCI has already been erroneously cleared. This can result in queue stalls on devices with multiple input queues. Fix it by clearing the DSCI just once, prior to scanning the queues. As the code is moved in front of the loop, we also need to access the DSCI directly (ie irq->dsci) instead of going via each queue's parent pointer to the same irq. This is not a functional change, and a follow-up patch will clean up the other users. In practice, this bug only affects CQ-enabled HiperSockets devices, ie. devices with sysfs-attribute "hsuid" set. Setting a hsuid is needed for AF_IUCV socket applications that use HiperSockets communication. Fixes: 104ea556ee7f ("qdio: support asynchronous delivery of storage blocks") Reviewed-by: Ursula Braun Signed-off-by: Julian Wiedmann Signed-off-by: Martin Schwidefsky Signed-off-by: Jiri Slaby

s390/chsc: fix SEI usage on old FW levels

2014-05-15T07:55:54Z

commit 06cd7a874ec6e09d151aeb1fa8600e14f1ff89f6 upstream. Using a notification type mask for the store event information chsc is unsupported on some firmware levels. Retry SEI with that mask set to zero (which is the old way of requesting only channel subsystem related events). Reported-and-tested-by: Stefan Haberland Reviewed-by: Peter Oberparleiter Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky Signed-off-by: Jiri Slaby

s390/cio: fix driver callback initialization for ccw consoles

2014-05-15T07:54:50Z

commit 2253e8d79237c69086ded391e6767afe16972527 upstream. ccw consoles are in use before they can be properly registered with the driver core. For devices which are in use by a device driver we rely on the ccw_device's pointer to the driver callbacks to be valid. For ccw consoles this pointer is NULL until they are registered later during boot and we dereferenced this pointer. This worked by chance on 64 bit builds (cdev->drv was NULL but the optional callback cdev->drv->path_event was also NULL by coincidence) and was unnoticed until we received reports about boot failures on 31 bit systems. Fix it by initializing the driver pointer for ccw consoles. Reported-by: Mike Frysinger Reported-by: Heiko Carstens Reviewed-by: Peter Oberparleiter Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky Signed-off-by: Jiri Slaby

s390/time: correct use of store clock fast

2013-10-22T07:16:40Z

The result of the store-clock-fast (STCKF) instruction is a bit fuzzy. It can happen that the value stored on one CPU is smaller than the value stored on another CPU, although the order of the stores is the other way around. This can cause deltas of get_tod_clock() values to become negative when they should not be. We need to be more careful with store-clock-fast, this patch partially reverts git commit e4b7b4238e666682555461fa52eecd74652f36bb "time: always use stckf instead of stck if available". The get_tod_clock() function now uses the store-clock-extended (STCKE) instruction. get_tod_clock_fast() can be used if the fuzziness of store-clock-fast is acceptable e.g. for wait loops local to a CPU. Signed-off-by: Martin Schwidefsky

s390/cio: fix unlocked access of global bitmap

2013-08-30T06:57:22Z

Access to the slow_subchannel_set has to be secured via the slow_subchannel_lock. Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky

s390/hibernate: add early resume function

2013-08-30T06:57:15Z

Some functions that do arch specific resume actions are called directly from swsusp_asm64.S . Before we add another function call provide a generic s390_early_resume function which can be used for this purpose. Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky

s390: convert interrupt handling to use generic hardirq

2013-08-22T10:20:04Z

With the introduction of PCI it became apparent that s390 should convert to generic hardirqs as too many drivers do not have the correct dependency for GENERIC_HARDIRQS. On the architecture level s390 does not have irq lines. It has external interrupts, I/O interrupts and adapter interrupts. This patch hard-codes all external interrupts as irq #1, all I/O interrupts as irq #2 and all adapter interrupts as irq #3. The additional information from the lowcore associated with the interrupt is stored in the pt_regs of the interrupt frame, where the interrupt handler can pick it up. For PCI/MSI interrupts the adapter interrupt handler scans the relevant bit fields and calls generic_handle_irq with the virtual irq number for the MSI interrupt. Reviewed-by: Sebastian Ott Signed-off-by: Martin Schwidefsky

s390/airq: introduce adapter interrupt vector helper

2013-08-22T10:20:02Z

The PCI code is the first user of adapter interrupts vectors. Add a set of helpers to airq.c to separate the adatper interrupt code from the PCI bits. The helpers allow for adapter interrupt vectors of any size. Reviewed-by: Sebastian Ott Signed-off-by: Martin Schwidefsky

s390: replace strict_strtoul() with kstrtoul()

2013-08-22T10:20:00Z

The usage of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/qdio: remove unused variable

2013-07-16T10:21:57Z

Fix a "set but not used" warning found via make W=1. Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky