There is no mutex protection of these state checking for 'stop'
and 'detach' which can't guarantee there is no another instance
is trying to do same operation.
Consider two instances case:
Instance1: echo stop > /sys/class/remoteproc/remoteproc0/state
Instance2: echo stop > /sys/class/remoteproc/remoteproc0/state
The issue is that the instance2 case may success, Or it
may fail with -EINVAL, which is uncertain.
So move this state checking in rproc_cdev_write() and
state_store() for 'stop', 'detach' operation to
'rproc_shutdown' , 'rproc_detach' function under the mutex
protection.
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1648434012-16655-3-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
There is no mutex protection of the state checking before rproc_boot(),
which can't guarantee there is no another instance is trying to do
same operation.
Consider two instances case:
Instance1: echo start > /sys/class/remoteproc/remoteproc0/state
Instance2: echo start > /sys/class/remoteproc/remoteproc0/state
...
Instance2: echo stop > /sys/class/remoteproc/remoteproc0/state
...
Instance1: echo stop > /sys/class/remoteproc/remoteproc0/state
The one issue is that the instance2 case may success when 'start'
happens at same time as instance1, then rproc->power = 2; Or it
may fail with -BUSY, then rproc->power = 1; which is uncertain.
The another issue is for 'stop' operation, if the rproc->power = 1,
when instance2 'stop' the remoteproc the instance1 will be
impacted for it still needs the service at that time.
The reference counter rproc->power is used to manage state
changing and there is mutex protection in each operation
function for multi instance case.
So remove this state checking in rproc_cdev_write() and
state_store() for 'start' operation, just let reference
counter rproc->power to manage the behaviors.
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1648434012-16655-2-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
The rproc_shutdown() function is currently not returning any
error code, and any failures within rproc_stop() are not passed
back to the users. Change the signature to return a success value
back to the callers.
The remoteproc sysfs and cdev interfaces are also updated to
return back this status to userspace.
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220213201246.25952-2-s-anna@ti.com
The rproc_char_device_remove() call currently unmaps the cdev
region instead of simply deleting the cdev that was added as a
part of the rproc_char_device_add() call. This change fixes that
behaviour, and also fixes the order in which device_del() and
cdev_del() need to be called.
Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
Link: https://lore.kernel.org/r/1623723671-5517-4-git-send-email-sidgup@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Refactor function rproc_cdev_release() to take into account the
current state of the remote processor when choosing the state to
transition to.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210312162453.1234145-18-mathieu.poirier@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
This patch introduces the capability to detach a remote processor
that has been attached to by the remoteproc core. For that to happen
a rproc::ops::detach() operation needs to be available.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20210312162453.1234145-17-mathieu.poirier@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Allow a remote processor that was started by another entity to be
switched off by the remoteproc core. For that to happen a
rproc::ops::stop() operation needs to be available.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20210312162453.1234145-16-mathieu.poirier@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
This patch takes into account scenarios where a remote processor
has been attached to when receiving a "start" command from sysfs.
As with the case with the running state, the command can't be
carried out if the remote processor is already in operation.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20210312162453.1234145-15-mathieu.poirier@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Add the character device interface into remoteproc framework.
This interface can be used in order to boot/shutdown remote
subsystems and provides a basic ioctl based interface to implement
supplementary functionality. An ioctl call is implemented to enable
the shutdown on release feature which will allow remote processors to
be shutdown when the controlling userspace application crashes or hangs.
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>
Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
Link: https://lore.kernel.org/r/1596044401-22083-2-git-send-email-sidgup@codeaurora.org
[bjorn: s/int32_t/s32/ per checkpatch]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Shengjiu Wang