kernel.git/drivers/s390/cio/device.c, branch linux-rolling-stable

s390: Remove KMSG_COMPONENT macro

2025-11-24T10:45:21Z

The KMSG_COMPONENT macro is a leftover of the s390 specific "kernel message catalog" which never made it upstream. Remove the macro in order to get rid of a pointless indirection. Replace all users with the string it defines. In almost all cases this leads to a simple replacement like this: - #define KMSG_COMPONENT "appldata" - #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + #define pr_fmt(fmt) "appldata: " fmt Except for some special cases this is just mechanical/scripted work. Acked-by: Thomas Richter Signed-off-by: Heiko Carstens

s390/cio: Update purge function to unregister the unused subchannels

2025-10-04T16:40:42Z

Starting with 'commit 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers")', cio no longer unregisters subchannels when the attached device is invalid or unavailable. As an unintended side-effect, the cio_ignore purge function no longer removes subchannels for devices on the cio_ignore list if no CCW device is attached. This situation occurs when a CCW device is non-operational or unavailable To ensure the same outcome of the purge function as when the current cio_ignore list had been active during boot, update the purge function to remove I/O subchannels without working CCW devices if the associated device number is found on the cio_ignore list. Fixes: 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers") Suggested-by: Peter Oberparleiter Reviewed-by: Peter Oberparleiter Signed-off-by: Vineeth Vijayan Signed-off-by: Heiko Carstens

s390/cio/device: Switch over to sysfs_emit()

2024-10-25T14:03:25Z

Per Documentation/filesystems/sysfs.rst, sysfs_emit() is preferred for presenting attributes to user space in sysfs. Convert the left-over uses in the cio/device code. Signed-off-by: Mete Durlu Acked-by: Vineeth Vijayan Tested-by: Vineeth Vijayan Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens

s390/cio: Do not unregister the subchannel based on DNV

2024-10-25T14:03:23Z

Starting with commit 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers"), CIO does not unregister subchannels when the attached device is invalid or unavailable. Instead, it allows subchannels to exist without a connected device. However, if the DNV value is 0, such as, when all the CHPIDs of a subchannel are configured in standby state, the subchannel is unregistered, which contradicts the current subchannel specification. Update the logic so that subchannels are not unregistered based on the DNV value. Also update the SCHIB information even if the DNV bit is zero. Suggested-by: Peter Oberparleiter Signed-off-by: Vineeth Vijayan Fixes: 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers") Reviewed-by: Peter Oberparleiter Signed-off-by: Heiko Carstens

driver core: have match() callback in struct bus_type take a const *

2024-07-03T13:16:54Z

In the match() callback, the struct device_driver * should not be changed, so change the function callback to be a const *. This is one step of many towards making the driver core safe to have struct device_driver in read-only memory. Because the match() callback is in all busses, all busses are modified to handle this properly. This does entail switching some container_of() calls to container_of_const() to properly handle the constant *. For some busses, like PCI and USB and HV, the const * is cast away in the match callback as those busses do want to modify those structures at this point in time (they have a local lock in the driver structure.) That will have to be changed in the future if they wish to have their struct device * in read-only-memory. Cc: Rafael J. Wysocki Reviewed-by: Alex Elder Acked-by: Sumit Garg Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh Signed-off-by: Greg Kroah-Hartman

s390/cio: fix race condition during online processing

2024-04-12T14:13:02Z

A race condition exists in ccw_device_set_online() that can cause the online process to fail, leaving the affected device in an inconsistent state. As a result, subsequent attempts to set that device online fail with return code ENODEV. The problem occurs when a path verification request arrives after a wait for final device state completed, but before the result state is evaluated. Fix this by ensuring that the CCW-device lock is held between determining final state and checking result state. Note that since: commit 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers") path verification requests are much more likely to occur during boot, resulting in an increased chance of this race condition occurring. Fixes: 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers") Reviewed-by: Alexandra Winter Reviewed-by: Vineeth Vijayan Signed-off-by: Peter Oberparleiter Signed-off-by: Alexander Gordeev

s390/cio: make ccw_bus_type const

2024-02-09T12:58:16Z

Now that the driver core can properly handle constant struct bus_type, move the ccw_bus_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Cc: Greg Kroah-Hartman Suggested-by: Greg Kroah-Hartman Signed-off-by: "Ricardo B. Marliere" Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20240203-bus_cleanup-s390-v1-3-ac891afc7282@marliere.net Signed-off-by: Heiko Carstens

s390/cio: make sch->lock spinlock pointer a member

2023-12-12T13:41:58Z

The lock member of struct subchannel used to be a spinlock, but became a pointer to a spinlock with commit 2ec2298412e1 ("[S390] subchannel lock conversion."). This might have been justified back then, but with the current state of affairs, there is no reason to manage a separate spinlock object. Let's simplify things and pull the spinlock back into struct subchannel. Signed-off-by: Halil Pasic Reviewed-by: Vineeth Vijayan Link: https://lore.kernel.org/r/20231101115751.2308307-1-pasic@linux.ibm.com Signed-off-by: Vasily Gorbik Signed-off-by: Alexander Gordeev

s390: fix various typos

2023-07-03T09:19:42Z

Fix various typos found with codespell. Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/cio: unregister device when the only path is gone

2023-05-22T10:45:44Z

Currently, if the device is offline and all the channel paths are either configured or varied offline, the associated subchannel gets unregistered. Don't unregister the subchannel, instead unregister offline device. Signed-off-by: Vineeth Vijayan Reviewed-by: Peter Oberparleiter Signed-off-by: Alexander Gordeev