On 01/02/07 09:15, Duncan Sands wrote: > On Thursday 1 February 2007 00:39:14 you wrote: >> On Tue, 30 Jan 2007 21:30:29 +0000 >> Simon Arlott <[email protected]> wrote: >> >>> +static int cxacru_proc_read(struct usbatm_data *usbatm_instance, >>> + struct atm_dev *atm_dev, loff_t * pos, char *page) >>> +{ >>> + struct cxacru_data *instance = usbatm_instance->driver_data; >>> + u32 *cxinf = instance->cxinf_status; >>> + int left = *pos; >>> + >>> + if (!left--) >>> + return sprintf(page, "# %s\n", usbatm_instance->description); >>> + >>> + if (!left--) { >>> + if (cxinf[CXINF_LINE_STATUS] == 5) { >>> + return sprintf(page, "# UP %u/%u\n", >>> + cxinf[CXINF_DOWNSTREAM_RATE], >>> + cxinf[CXINF_UPSTREAM_RATE]); >>> + } else { >>> + return sprintf(page, "# DOWN\n"); >>> + } >>> + } >> hm, how well-tested was this proc interface? The pread() and lseek() >> behaviour might be strange. >> >> I guess as long as it doesn't oops, hang or anything like that then it'll >> be OK. Anyone who does anything apart from a single big-fat-read from a >> procfile has a good chance of getting into trouble :( Well, several reads of at least 172B... but that scenario works without any problems. > All the ATM drivers seem to do it like this. That doesn't mean they are > right of course! But I never saw anyone complain on the ATM mailing list. I just copied it from usbatm; it looks like this could be done using seq_file instead. > On the other hand, why does Simon want this? If he has written a user space > tool that extracts bits from the proc file (eg: to tell users what's going > on) then he could run into trouble, depending on how he implements it. No special user space tool, I just want other people to be able to get the same useful line information from cxacru that most ADSL driver have. (I do have a small "cxacru-watch" program which execs "cmd.up" etc. on status changes, but that is just sent printks via syslog-ng). It looks like the weird proc interface prevents my intention to allow ". /proc/net/atm/cxacru\:0" to work and set $LINE_STATUS etc., at least with bash: open("/proc/net/atm/cxacru:0", O_RDONLY|O_LARGEFILE) = 3 fstat64(3, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0 read(3, "", 0) = 0 close(3) = 0 Does anyone have any thoughts on the output format? The standard usbatm output isn't going to be compatible with the above if a common MAC/AAL5 header were used. When I have the time and can acquire another conexant usb modem for testing I'll fix the usbatm /proc interfaces. It would be also good if the module could reliably be reloaded - most (but not all) of the time it fails to initialise the device again. There's still an issue with khubd going into a loop if the firmware doesn't exist or if the device is unplugged. -- Simon Arlott
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- References:
- [PATCH 3/3] cxacru: Store all device status information and report it when atm_proc_read is called.
- From: Simon Arlott <[email protected]>
- Re: [PATCH 3/3] cxacru: Store all device status information and report it when atm_proc_read is called.
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- Re: [PATCH 3/3] cxacru: Store all device status information and report it when atm_proc_read is called.
- From: Duncan Sands <[email protected]>
- [PATCH 3/3] cxacru: Store all device status information and report it when atm_proc_read is called.
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