| Message ID | 20230817093231.2317-1-daniel.starke@siemens.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v6,1/9] tty: n_gsm: add restart flag to DLC specific ioctl config | expand |
On Tue, Aug 22, 2023 at 03:05:10PM +0200, Greg KH wrote: > On Thu, Aug 17, 2023 at 11:32:23AM +0200, D. Starke wrote: > > From: Daniel Starke <daniel.starke@siemens.com> > > > > Currently, changing the parameters of a DLCI gives no direct control to the > > user whether this should trigger a channel reset or not. The decision is > > solely made by the driver based on the assumption which parameter changes > > are compatible or not. Therefore, the user has no means to perform an > > automatic channel reset after parameter configuration for non-conflicting > > changes. > > > > Add the parameter 'flags' to 'gsm_dlci_config' to force a channel reset > > after ioctl setting regardless of whether the changes made require this or > > not by setting this to 'GSM_FL_RESTART'. > > > > Note that 'GSM_FL_RESTART' is currently the only allow flag to allow > > additions here. > > > > Signed-off-by: Daniel Starke <daniel.starke@siemens.com> > > --- > > drivers/tty/n_gsm.c | 4 ++++ > > include/uapi/linux/gsmmux.h | 15 ++++++++++++++- > > 2 files changed, 18 insertions(+), 1 deletion(-) > > > > v5 -> v6: > > No changes. > > > > Link: https://lore.kernel.org/all/20230517155704.5701-1-daniel.starke@siemens.com/ > > > > diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c > > index 42759500b79e..a4268515920e 100644 > > --- a/drivers/tty/n_gsm.c > > +++ b/drivers/tty/n_gsm.c > > @@ -2532,6 +2532,8 @@ static int gsm_dlci_config(struct gsm_dlci *dlci, struct gsm_dlci_config *dc, in > > return -EINVAL; > > if (dc->k > 7) > > return -EINVAL; > > + if (dc->flags & ~GSM_FL_RESTART) /* allow future extensions */ > > + return -EINVAL; > > > > /* > > * See what is needed for reconfiguration > > @@ -2546,6 +2548,8 @@ static int gsm_dlci_config(struct gsm_dlci *dlci, struct gsm_dlci_config *dc, in > > /* Requires care */ > > if (dc->priority != dlci->prio) > > need_restart = true; > > + if (dc->flags & GSM_FL_RESTART) > > + need_restart = true; > > > > if ((open && gsm->wait_config) || need_restart) > > need_open = true; > > diff --git a/include/uapi/linux/gsmmux.h b/include/uapi/linux/gsmmux.h > > index eb67884e5f38..e56e2d7ea6eb 100644 > > --- a/include/uapi/linux/gsmmux.h > > +++ b/include/uapi/linux/gsmmux.h > > @@ -2,10 +2,22 @@ > > #ifndef _LINUX_GSMMUX_H > > #define _LINUX_GSMMUX_H > > > > +#include <linux/const.h> > > #include <linux/if.h> > > #include <linux/ioctl.h> > > #include <linux/types.h> > > > > +/* > > + * flags definition for n_gsm > > + * > > + * Used by: > > + * struct gsm_dlci_config.flags > > + */ > > +/* Forces a DLCI reset if set. Otherwise, a DLCI reset is only done if > > + * incompatible settings were provided. Always cleared on retrieval. > > + */ > > +#define GSM_FL_RESTART _BITUL(0) > > + > > struct gsm_config > > { > > unsigned int adaption; > > @@ -58,7 +70,8 @@ struct gsm_dlci_config { > > __u32 priority; /* Priority (0 for default value) */ > > __u32 i; /* Frame type (1 = UIH, 2 = UI) */ > > __u32 k; /* Window size (0 for default value) */ > > - __u32 reserved[8]; /* For future use, must be initialized to zero */ > > + __u32 flags; /* DLCI specific flags. */ > > This should be called "dlci_flags" right? Otherwise when you add more > flags in the reserved area, what will you call them? Oh nevermind, the name of the structure has it there, this is fine, I'll take this... thanks, greg k-h
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 42759500b79e..a4268515920e 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -2532,6 +2532,8 @@ static int gsm_dlci_config(struct gsm_dlci *dlci, struct gsm_dlci_config *dc, in return -EINVAL; if (dc->k > 7) return -EINVAL; + if (dc->flags & ~GSM_FL_RESTART) /* allow future extensions */ + return -EINVAL; /* * See what is needed for reconfiguration @@ -2546,6 +2548,8 @@ static int gsm_dlci_config(struct gsm_dlci *dlci, struct gsm_dlci_config *dc, in /* Requires care */ if (dc->priority != dlci->prio) need_restart = true; + if (dc->flags & GSM_FL_RESTART) + need_restart = true; if ((open && gsm->wait_config) || need_restart) need_open = true; diff --git a/include/uapi/linux/gsmmux.h b/include/uapi/linux/gsmmux.h index eb67884e5f38..e56e2d7ea6eb 100644 --- a/include/uapi/linux/gsmmux.h +++ b/include/uapi/linux/gsmmux.h @@ -2,10 +2,22 @@ #ifndef _LINUX_GSMMUX_H #define _LINUX_GSMMUX_H +#include <linux/const.h> #include <linux/if.h> #include <linux/ioctl.h> #include <linux/types.h> +/* + * flags definition for n_gsm + * + * Used by: + * struct gsm_dlci_config.flags + */ +/* Forces a DLCI reset if set. Otherwise, a DLCI reset is only done if + * incompatible settings were provided. Always cleared on retrieval. + */ +#define GSM_FL_RESTART _BITUL(0) + struct gsm_config { unsigned int adaption; @@ -58,7 +70,8 @@ struct gsm_dlci_config { __u32 priority; /* Priority (0 for default value) */ __u32 i; /* Frame type (1 = UIH, 2 = UI) */ __u32 k; /* Window size (0 for default value) */ - __u32 reserved[8]; /* For future use, must be initialized to zero */ + __u32 flags; /* DLCI specific flags. */ + __u32 reserved[7]; /* For future use, must be initialized to zero */ }; #define GSMIOC_GETCONF_DLCI _IOWR('G', 7, struct gsm_dlci_config)