I am of the same mind here regarding the busy check, better to have a coarse or overly paranoid understanding of ref count. But we desire a ref count on the disk (/dev/sda) overall, not on the partition (/dev/sda2) as would typically be mounted. As for using fuser as James had suggested, needing to check each partition for a user count is just wrong and time consuming and flawed when someone makes their own dev 'elsewhere' to access the disk. I want to know if the disk is busy, not the partitions, and not have to check the multitude of individual possible access points to the disk before satiating my need. Our folks freaked when I suggested they use 'popen()' to pick up the response from fuser. They view that as a security hole. And I am sure to be flamed for this, importing open source fuser code got the 'proprietary gohds' also equally messed up (GPL infects, BSD relieves stomach ulcers). Sincerely -- Mark Salyzyn -----Original Message----- From: linux-scsi-owner@xxxxxxxxxxxxxxx [mailto:linux-scsi-owner@xxxxxxxxxxxxxxx] On Behalf Of Harald Seipp Sent: Friday, August 12, 2005 4:59 AM To: Bryan Henderson Cc: James Bottomley; SCSI Mailing List Subject: Re: remove-single-device removes mounted HDDs (kernel 2.6) > Don't use /etc/mtab. Don't use it for anything if you can help it; it was > important technology in its day, but we can now go to the horse's mouth -- > the kernel -- for that information. > /proc/mounts will tell you what is really mounted. But: 1. /proc/mounts hides the most important information - the physical device of the root fs - it will always be /dev/root - so I don't see a way to get down to the physical device 2. In my understanding, long-term-strategically procfs will only be used for process information and all other information should be covered by sysfs. So I doubt that using /proc/mounts will be a long-term solution > > As you mentioned in another posting, this isn't really the information you > want either -- you want to know if the SCSI disk is in use. Being the > device backing a conventional filesystem image is only one way a SCSI disk > might be in use. For our usage, the device ref count information would be enough - we won't care about the difference if the device is really mounted or if just one process is sitting inside the sysfs tree of the device, we just would not issue the remove-single-device to that device. Harald Seipp IBM Systems and Technology Group - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
