firedtv: change some -EFAULT returns to more fitting error codes
Commit Message
Mauro Carvalho Chehab wrote:
> I'm validating if all drivers are behaving equally with respect to the
> error codes returned to userspace, and double-checking with the API.
>
> On almost all places, -EFAULT code is used only to indicate when
> copy_from_user/copy_to_user fails. However, firedtv uses a lot of
> -EFAULT, where it seems to me that other error codes should be used
> instead (like -EIO for bus transfer errors and -EINVAL/-ERANGE for
> invalid/out of range parameters).
This concerns only the CI (CAM) related code of firedtv of which I know
little. Let's just pass through the error returns of lower level I/O
code where applicable, and -EACCES (permission denied) when a seemingly
valid but negative FCP response or an unknown-to-firedtv CA message is
received.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Henrik Kurelid <henrik@kurelid.se>
---
Only tested on FireDTV-{C,T}/CI without CAM.
drivers/media/dvb/firewire/firedtv-avc.c | 2
drivers/media/dvb/firewire/firedtv-ci.c | 34 +++++++++++------------
2 files changed, 17 insertions(+), 19 deletions(-)
static int fdtv_ca_get_msg(struct firedtv *fdtv, void *arg)
@@ -111,14 +108,15 @@ static int fdtv_ca_get_msg(struct firedt
err = fdtv_ca_info(fdtv, arg);
break;
default:
- if (avc_tuner_status(fdtv, &stat))
- err = -EFAULT;
- else if (stat.ca_mmi == 1)
+ err = avc_tuner_status(fdtv, &stat);
+ if (err)
+ break;
+ if (stat.ca_mmi == 1)
err = fdtv_ca_get_mmi(fdtv, arg);
else {
dev_info(fdtv->device, "unhandled CA message
0x%08x\n", fdtv->ca_last_command);
- err = -EFAULT;
+ err = -EACCES;
}
}
fdtv->ca_last_command = 0;
@@ -141,7 +139,7 @@ static int fdtv_ca_pmt(struct firedtv *f
data_length = msg->msg[3];
}
- return avc_ca_pmt(fdtv, &msg->msg[data_pos], data_length) ?
-EFAULT : 0;
+ return avc_ca_pmt(fdtv, &msg->msg[data_pos], data_length);
}
static int fdtv_ca_send_msg(struct firedtv *fdtv, void *arg)
@@ -170,7 +168,7 @@ static int fdtv_ca_send_msg(struct fired
default:
dev_err(fdtv->device, "unhandled CA message 0x%08x\n",
fdtv->ca_last_command);
- err = -EFAULT;
+ err = -EACCES;
}
return err;
}
@@ -184,7 +182,7 @@ static int fdtv_ca_ioctl(struct file *fi
switch (cmd) {
case CA_RESET:
- err = fdtv_ca_reset(fdtv);
+ err = avc_ca_reset(fdtv);
break;
case CA_GET_CAP:
err = fdtv_ca_get_caps(arg);
Comments
Hi Stefan,
Em 06-07-2011 14:33, Stefan Richter escreveu:
> Mauro Carvalho Chehab wrote:
>> I'm validating if all drivers are behaving equally with respect to the
>> error codes returned to userspace, and double-checking with the API.
>>
>> On almost all places, -EFAULT code is used only to indicate when
>> copy_from_user/copy_to_user fails. However, firedtv uses a lot of
>> -EFAULT, where it seems to me that other error codes should be used
>> instead (like -EIO for bus transfer errors and -EINVAL/-ERANGE for
>> invalid/out of range parameters).
Thanks for the patch! Unfortunately, it didn't arrived fine here (it was
whitespace mangled). Could you please re-send it with the proper whitespacing (or
attached)?
>
> This concerns only the CI (CAM) related code of firedtv of which I know
> little. Let's just pass through the error returns of lower level I/O
> code where applicable, and -EACCES (permission denied) when a seemingly
> valid but negative FCP response or an unknown-to-firedtv CA message is
> received.
Works for me.
>
> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
> Cc: Henrik Kurelid <henrik@kurelid.se>
> ---
> Only tested on FireDTV-{C,T}/CI without CAM.
>
> drivers/media/dvb/firewire/firedtv-avc.c | 2
> drivers/media/dvb/firewire/firedtv-ci.c | 34 +++++++++++------------
> 2 files changed, 17 insertions(+), 19 deletions(-)
>
> Index: b/drivers/media/dvb/firewire/firedtv-avc.c
> ===================================================================
> --- a/drivers/media/dvb/firewire/firedtv-avc.c
> +++ b/drivers/media/dvb/firewire/firedtv-avc.c
> @@ -1208,7 +1208,7 @@ int avc_ca_pmt(struct firedtv *fdtv, cha
> if (r->response != AVC_RESPONSE_ACCEPTED) {
> dev_err(fdtv->device,
> "CA PMT failed with response 0x%x\n",
> r->response);
> - ret = -EFAULT;
> + ret = -EACCES;
> }
> out:
> mutex_unlock(&fdtv->avc_mutex);
> Index: b/drivers/media/dvb/firewire/firedtv-ci.c
> ===================================================================
> --- a/drivers/media/dvb/firewire/firedtv-ci.c
> +++ b/drivers/media/dvb/firewire/firedtv-ci.c
> @@ -45,11 +45,6 @@ static int fdtv_get_ca_flags(struct fire
> return flags;
> }
>
> -static int fdtv_ca_reset(struct firedtv *fdtv)
> -{
> - return avc_ca_reset(fdtv) ? -EFAULT : 0;
> -}
> -
> static int fdtv_ca_get_caps(void *arg)
> {
> struct ca_caps *cap = arg;
> @@ -65,12 +60,14 @@ static int fdtv_ca_get_slot_info(struct
> {
> struct firedtv_tuner_status stat;
> struct ca_slot_info *slot = arg;
> + int err;
>
> - if (avc_tuner_status(fdtv, &stat))
> - return -EFAULT;
> + err = avc_tuner_status(fdtv, &stat);
> + if (err)
> + return err;
>
> if (slot->num != 0)
> - return -EFAULT;
> + return -EACCES;
>
> slot->type = CA_CI;
> slot->flags = fdtv_get_ca_flags(&stat);
> @@ -81,21 +78,21 @@ static int fdtv_ca_app_info(struct fired
> {
> struct ca_msg *reply = arg;
>
> - return avc_ca_app_info(fdtv, reply->msg, &reply->length) ?
> -EFAULT : 0;
> + return avc_ca_app_info(fdtv, reply->msg, &reply->length);
> }
>
> static int fdtv_ca_info(struct firedtv *fdtv, void *arg)
> {
> struct ca_msg *reply = arg;
>
> - return avc_ca_info(fdtv, reply->msg, &reply->length) ? -EFAULT :
> 0;
> + return avc_ca_info(fdtv, reply->msg, &reply->length);
> }
>
> static int fdtv_ca_get_mmi(struct firedtv *fdtv, void *arg)
> {
> struct ca_msg *reply = arg;
>
> - return avc_ca_get_mmi(fdtv, reply->msg, &reply->length) ?
> -EFAULT : 0;
> + return avc_ca_get_mmi(fdtv, reply->msg, &reply->length);
> }
>
> static int fdtv_ca_get_msg(struct firedtv *fdtv, void *arg)
> @@ -111,14 +108,15 @@ static int fdtv_ca_get_msg(struct firedt
> err = fdtv_ca_info(fdtv, arg);
> break;
> default:
> - if (avc_tuner_status(fdtv, &stat))
> - err = -EFAULT;
> - else if (stat.ca_mmi == 1)
> + err = avc_tuner_status(fdtv, &stat);
> + if (err)
> + break;
> + if (stat.ca_mmi == 1)
> err = fdtv_ca_get_mmi(fdtv, arg);
> else {
> dev_info(fdtv->device, "unhandled CA message
> 0x%08x\n", fdtv->ca_last_command);
> - err = -EFAULT;
> + err = -EACCES;
> }
> }
> fdtv->ca_last_command = 0;
> @@ -141,7 +139,7 @@ static int fdtv_ca_pmt(struct firedtv *f
> data_length = msg->msg[3];
> }
>
> - return avc_ca_pmt(fdtv, &msg->msg[data_pos], data_length) ?
> -EFAULT : 0;
> + return avc_ca_pmt(fdtv, &msg->msg[data_pos], data_length);
> }
>
> static int fdtv_ca_send_msg(struct firedtv *fdtv, void *arg)
> @@ -170,7 +168,7 @@ static int fdtv_ca_send_msg(struct fired
> default:
> dev_err(fdtv->device, "unhandled CA message 0x%08x\n",
> fdtv->ca_last_command);
> - err = -EFAULT;
> + err = -EACCES;
> }
> return err;
> }
> @@ -184,7 +182,7 @@ static int fdtv_ca_ioctl(struct file *fi
>
> switch (cmd) {
> case CA_RESET:
> - err = fdtv_ca_reset(fdtv);
> + err = avc_ca_reset(fdtv);
> break;
> case CA_GET_CAP:
> err = fdtv_ca_get_caps(arg);
>
>
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===================================================================
@@ -1208,7 +1208,7 @@ int avc_ca_pmt(struct firedtv *fdtv, cha
if (r->response != AVC_RESPONSE_ACCEPTED) {
dev_err(fdtv->device,
"CA PMT failed with response 0x%x\n",
r->response);
- ret = -EFAULT;
+ ret = -EACCES;
}
out:
mutex_unlock(&fdtv->avc_mutex);
===================================================================
@@ -45,11 +45,6 @@ static int fdtv_get_ca_flags(struct fire
return flags;
}
-static int fdtv_ca_reset(struct firedtv *fdtv)
-{
- return avc_ca_reset(fdtv) ? -EFAULT : 0;
-}
-
static int fdtv_ca_get_caps(void *arg)
{
struct ca_caps *cap = arg;
@@ -65,12 +60,14 @@ static int fdtv_ca_get_slot_info(struct
{
struct firedtv_tuner_status stat;
struct ca_slot_info *slot = arg;
+ int err;
- if (avc_tuner_status(fdtv, &stat))
- return -EFAULT;
+ err = avc_tuner_status(fdtv, &stat);
+ if (err)
+ return err;
if (slot->num != 0)
- return -EFAULT;
+ return -EACCES;
slot->type = CA_CI;
slot->flags = fdtv_get_ca_flags(&stat);
@@ -81,21 +78,21 @@ static int fdtv_ca_app_info(struct fired
{
struct ca_msg *reply = arg;
- return avc_ca_app_info(fdtv, reply->msg, &reply->length) ?
-EFAULT : 0;
+ return avc_ca_app_info(fdtv, reply->msg, &reply->length);
}
static int fdtv_ca_info(struct firedtv *fdtv, void *arg)
{
struct ca_msg *reply = arg;
- return avc_ca_info(fdtv, reply->msg, &reply->length) ? -EFAULT :
0;
+ return avc_ca_info(fdtv, reply->msg, &reply->length);
}
static int fdtv_ca_get_mmi(struct firedtv *fdtv, void *arg)
{
struct ca_msg *reply = arg;
- return avc_ca_get_mmi(fdtv, reply->msg, &reply->length) ?
-EFAULT : 0;
+ return avc_ca_get_mmi(fdtv, reply->msg, &reply->length);
}