linux-dev/drivers/s390/cio/chp.c, branch linus/master

s390: replace snprintf in show functions with sysfs_emit

2021-11-16T11:29:19Z

show() must not use snprintf() when formatting the value to be returned to user space. Fix the coccicheck warnings: WARNING: use scnprintf or sprintf. Use sysfs_emit instead of scnprintf or sprintf makes more sense. Signed-off-by: Qing Wang Acked-by: Vineeth Vijayan Acked-by: Stefan Haberland Link: https://lore.kernel.org/r/1634280655-4908-1-git-send-email-wangqing@vivo.com [hca@linux.ibm.com: fix indentation] Signed-off-by: Heiko Carstens

s390/cio: dont call css_wait_for_slow_path() inside a lock

2021-06-18T14:41:19Z

Currently css_wait_for_slow_path() gets called inside the chp->lock. The path-verification-loop of slowpath inside this lock could lead to deadlock as reported by the lockdep validator. The ccw_device_get_chp_desc() during the instance of a device-set-online would try to acquire the same 'chp->lock' to read the chp->desc. The instance of this function can get called from multiple scenario, like probing or setting-device online manually. This could, in some corner-cases lead to the deadlock. lockdep validator reported this as, CPU0 CPU1 ---- ---- lock(&chp->lock); lock(kn->active#43); lock(&chp->lock); lock((wq_completion)cio); The chp->lock was introduced to serialize the access of struct channel_path. This lock is not needed for the css_wait_for_slow_path() function, so invoke the slow-path function outside this lock. Fixes: b730f3a93395 ("[S390] cio: add lock to struct channel_path") Cc: Reviewed-by: Peter Oberparleiter Signed-off-by: Vineeth Vijayan Signed-off-by: Vasily Gorbik

s390/cio: use DECLARE_WAIT_QUEUE_HEAD for static work_queue_head_t

2021-04-12T10:46:41Z

Use DECLARE_WAIT_QUEUE_HEAD to declare and statically initialize the work_queue_head_t. Signed-off-by: Vineeth Vijayan Reviewed-by: Peter Oberparleiter Signed-off-by: Heiko Carstens

s390/cio: Export information about Endpoint-Security Capability

2020-11-16T15:14:37Z

Add a new sysfs attribute 'esc' per chpid. This new attribute exports the Endpoint-Security-Capability byte of channel-path description block, which could be 0-None, 1-Authentication, 2 and 3-Encryption. For example: $ cat /sys/devices/css0/chp0.34/esc 0 [vneethv@linux.ibm.com: cleaned-up & modified description] Signed-off-by: Sebastian Ott Signed-off-by: Vineeth Vijayan Signed-off-by: Stefan Haberland Reviewed-by: Jan Höppner Reviewed-by: Peter Oberparleiter Reviewed-by: Cornelia Huck Acked-by: Vasily Gorbik Signed-off-by: Jens Axboe

s390/cio: use kobj_to_dev() API

2020-02-17T17:01:57Z

Use kobj_to_dev() API instead of container_of(). Reviewed-by: Cornelia Huck Signed-off-by: chenqiwu Signed-off-by: chenqiwu Message-Id: <1581688293-17283-1-git-send-email-qiwuchen55@gmail.com> Signed-off-by: Vasily Gorbik

s390/cio: ensure that a chpid is registered only once

2018-07-17T05:27:51Z

Improve locking in chp_new to make sure that we don't register the same chpid twice. Chpid registration was synchronized via the machine check handler thread but we also have codepaths to look for new chpids triggered independent of that thread (during IPL or resume from hibernate). Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky

s390/cio: add util_string sysfs attribute

2018-03-28T06:38:22Z

Export utility strings as a chpid's binary sysfs attribute. Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky

s390/chsc: query utility strings via fmt3 channel path descriptor

2018-03-26T14:13:16Z

Add support for format 3 channel path descriptors and use them to gather utility strings. Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky

s390/cio: rename struct channel_path_desc

2018-03-26T14:13:11Z

Rename struct channel_path_desc to struct channel_path_desc_fmt0 to fit the scheme. Provide a macro for the function wrappers that gather this and related data from firmware. Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky

s390/cio: fix kernel-doc usage

2018-02-05T06:34:52Z

Fix the kernel-doc usage in cio to get rid of (W=1) build warnings like: drivers/s390/cio/cio.c:1068: warning: No description found for parameter 'sch' Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky