Re: [PATCH] sgiioc4 driver needs /proc/ide entries

[Bartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>]

On Wednesday 08 September 2004 18:17, Erik Jacobson wrote:
> The patch below makes it so the proper /proc/ide files are created when
> this driver is loaded.  Previously, /proc/ide would be empty even though

This patch only adds /proc/ide/sgiioc4 entry.
/proc/ide should be properly populated without it.

> the devices could be used, etc.  This is creating problems for us because
> some installers and daemons expect the proc files to be in place.

Please name these installers and daemons.

If your application is checking for /proc/ide/sgiioc4 this is WRONG.

Please tell us what do you need this information for and we can
see what can be done.

> We're open to comments but would appreciate this being accepted ASAP
> as this problem is affecting our progress on some projects.
>
> I verified this exact patch works on 2.6.9-rc1 (and it applies without
> fuzz).
> 
> One thing I'll probably hear about is that we create /proc/ide/sgiioc4
> but don't produce info and metrics for it.  We may elect to produce some

Actually no, these /proc/ide/<chipset> entries are just bloat and should
be removed - basic info should be always printed on the console (i.e. while
changing transfer mode) and more advanced info should be only printed
while debugging driver.

> metrics later but this driver is used primarily for the system CDROM and
> having metrics there isn't a priority at this moment.  So I create the proc
> file anyway but it just reports the type of driver it is.
> 
> diffstat:
> 
>  drivers/ide/pci/sgiioc4.c |   33 +++++++++++++++++++++++++++++++++
>  1 files changed, 33 insertions(+)
> 
> Signed-off-by: Erik Jacobson <erikj@sgi.com>
> 
> 
> diff -Naru linux-2.6.8-orig/drivers/ide/pci/sgiioc4.c linux-2.6.8/drivers/ide/pci/sgiioc4.c
> --- linux-2.6.8-orig/drivers/ide/pci/sgiioc4.c	2004-08-14 01:36:58.000000000 -0400
> +++ linux-2.6.8/drivers/ide/pci/sgiioc4.c	2004-09-08 08:40:39.624159397 -0400
> @@ -34,6 +34,7 @@
>  #include <linux/mm.h>
>  #include <linux/ioport.h>
>  #include <linux/blkdev.h>
> +#include <linux/proc_fs.h>
>  #include <asm/io.h>
> 
>  #include <linux/ide.h>
> @@ -92,6 +93,27 @@
>  #define IOC4_PRD_BYTES       16
>  #define IOC4_PRD_ENTRIES     (PAGE_SIZE /(4*IOC4_PRD_BYTES))
> 
> +/* Used so we only try to create the /proc/ide/sgiioc4 entry once. */
> +static u8 sgiioc4_proc;
> +
> +/* Produce output for /proc/ide/sgiioc4:
> + * At this point, we don't produce any metrics information.
> + * Still, it seems we should create this so we behave like other IDE
> + * drivers do.  Perhaps someone will write in metrics information some day
> + * and that can be hooked in here.
> + */
> +static int sgiioc4_get_info(char *buffer, char **addr, off_t offset, int count)
> +{
> +	char *p = buffer;
> +	int len;
> +
> +	p += sprintf(p, "\nSGI IOC4 IDE Driver\n");
> +	p += sprintf(p, "This space may be used in the future for metrics.\n");
> +
> +	len = (p - buffer) - offset;
> +	*addr = buffer + offset;
> +	return len > count ? count : len;
> +}
> 
>  static void
>  sgiioc4_init_hwif_ports(hw_regs_t * hw, unsigned long data_port,
> @@ -702,6 +724,10 @@
>  		       hwif->name, d->name);
> 
>  	probe_hwif_init(hwif);
> +
> +	/* Create /proc/ide entries */
> +	create_proc_ide_interfaces();
> +
>  	return 0;
>  }
> 
> @@ -732,6 +758,13 @@
> 
>  	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_rev);
>  	class_rev &= 0xff;
> +
> +	/* create /proc/ide/sgiioc4 entry */
> +	if (!sgiioc4_proc) {
> +		ide_pci_create_host_proc("sgiioc4", sgiioc4_get_info);
> +		sgiioc4_proc = 1;
> +	}
> +
>  	printk(KERN_INFO "%s: IDE controller at PCI slot %s, revision %d\n",
>  			d->name, dev->slot_name, class_rev);
>  	if (class_rev < IOC4_SUPPORTED_FIRMWARE_REV) {
> 
>