On Mon, Mar 22, 2021 at 10:49 PM Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx> wrote: > > From: Tomas Winkler <tomas.winkler@xxxxxxxxx> > > Allow map and unmap of the client dma buffer only when the client is not > connected. The functions return -EPROTO if the client is already connected. > This is to fix the race when traffic may start or stop when buffer > is not available. > > Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx> > Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx> This one has been taken by Greg through his tree so I'll drop it. I won't resend the series for this though. > --- > drivers/misc/mei/client.c | 17 +++++++---------- > 1 file changed, 7 insertions(+), 10 deletions(-) > > diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c > index 4378a9b25848..2cc370adb238 100644 > --- a/drivers/misc/mei/client.c > +++ b/drivers/misc/mei/client.c > @@ -2286,8 +2286,8 @@ int mei_cl_dma_alloc_and_map(struct mei_cl *cl, const struct file *fp, > if (buffer_id == 0) > return -EINVAL; > > - if (!mei_cl_is_connected(cl)) > - return -ENODEV; > + if (mei_cl_is_connected(cl)) > + return -EPROTO; > > if (cl->dma_mapped) > return -EPROTO; > @@ -2327,9 +2327,7 @@ int mei_cl_dma_alloc_and_map(struct mei_cl *cl, const struct file *fp, > > mutex_unlock(&dev->device_lock); > wait_event_timeout(cl->wait, > - cl->dma_mapped || > - cl->status || > - !mei_cl_is_connected(cl), > + cl->dma_mapped || cl->status, > mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT)); > mutex_lock(&dev->device_lock); > > @@ -2376,8 +2374,9 @@ int mei_cl_dma_unmap(struct mei_cl *cl, const struct file *fp) > return -EOPNOTSUPP; > } > > - if (!mei_cl_is_connected(cl)) > - return -ENODEV; > + /* do not allow unmap for connected client */ > + if (mei_cl_is_connected(cl)) > + return -EPROTO; > > if (!cl->dma_mapped) > return -EPROTO; > @@ -2405,9 +2404,7 @@ int mei_cl_dma_unmap(struct mei_cl *cl, const struct file *fp) > > mutex_unlock(&dev->device_lock); > wait_event_timeout(cl->wait, > - !cl->dma_mapped || > - cl->status || > - !mei_cl_is_connected(cl), > + !cl->dma_mapped || cl->status, > mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT)); > mutex_lock(&dev->device_lock); > > -- > 2.25.1 >
