* "block" symlink in sysfs for a multifunction device @ 2005-12-12 21:49 Pete Zaitcev 2005-12-12 21:53 ` Russell King 2005-12-14 5:50 ` Greg KH 0 siblings, 2 replies; 11+ messages in thread From: Pete Zaitcev @ 2005-12-12 21:49 UTC (permalink / raw) To: greg; +Cc: linux-kernel Hi, Greg, When I plug a USB card reader with multiply LUNs, the following happens: [zaitcev@niphredil ~]$ ls -l /sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0 total 0 -r--r--r-- 1 root root 4096 Dec 12 12:47 bAlternateSetting -r--r--r-- 1 root root 4096 Dec 12 12:46 bInterfaceClass -r--r--r-- 1 root root 4096 Dec 12 12:46 bInterfaceNumber -r--r--r-- 1 root root 4096 Dec 12 12:46 bInterfaceProtocol -r--r--r-- 1 root root 4096 Dec 12 12:46 bInterfaceSubClass lrwxrwxrwx 1 root root 0 Dec 12 12:47 block -> ../../../../../../block/ubd lrwxrwxrwx 1 root root 0 Dec 12 12:47 block -> ../../../../../../block/ubd lrwxrwxrwx 1 root root 0 Dec 12 12:47 block -> ../../../../../../block/ubd lrwxrwxrwx 1 root root 0 Dec 12 12:47 block -> ../../../../../../block/ubd -r--r--r-- 1 root root 4096 Dec 12 12:46 bNumEndpoints lrwxrwxrwx 1 root root 0 Dec 12 12:46 bus -> ../../../../../../bus/usb -r--r--r-- 1 root root 4096 Dec 12 12:47 diag lrwxrwxrwx 1 root root 0 Dec 12 12:46 driver -> ../../../../../../bus/usb/drivers/ub -r--r--r-- 1 root root 4096 Dec 12 12:46 modalias drwxr-xr-x 2 root root 0 Dec 12 12:46 power [zaitcev@niphredil ~]$ cat /proc/version Linux version 2.6.14-nip (zaitcev@niphredil) (gcc version 4.0.2 20051109 (Red Hat 4.0.2-6)) #5 Tue Dec 6 23:10:53 PST 2005 [zaitcev@niphredil ~]$ The usb-storage produces this: [root@niphredil linux-2.6.14-nip]# find /sys -name block /sys/block /sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0/host0/target0:0:0/0:0:0:3/block /sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0/host0/target0:0:0/0:0:0:2/block /sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0/host0/target0:0:0/0:0:0:1/block /sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0/host0/target0:0:0/0:0:0:0/block /sys/devices/pci0000:00/0000:00:07.1/ide0/0.0/block [root@niphredil linux-2.6.14-nip]# ls -l /sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0/host0/target0:0:0/0:0:0:0/block lrwxrwxrwx 1 root root 0 Dec 12 13:44 /sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0/host0/target0:0:0/0:0:0:0/block -> ../../../../../../../../../block/sda [root@niphredil linux-2.6.14-nip]# Each "block" is in its own subdirectory. Do you have a suggestion about the fastest way to accomplish the same effect with ub? Thank you, -- Pete ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-12 21:49 "block" symlink in sysfs for a multifunction device Pete Zaitcev @ 2005-12-12 21:53 ` Russell King 2005-12-14 5:50 ` Greg KH 1 sibling, 0 replies; 11+ messages in thread From: Russell King @ 2005-12-12 21:53 UTC (permalink / raw) To: Pete Zaitcev; +Cc: greg, linux-kernel On Mon, Dec 12, 2005 at 01:49:04PM -0800, Pete Zaitcev wrote: > Do you have a suggestion about the fastest way to accomplish the same > effect with ub? Note: same thing happens with floppy if you have two floppy drives connected to the controller. You end up with two "block" symlinks. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-12 21:49 "block" symlink in sysfs for a multifunction device Pete Zaitcev 2005-12-12 21:53 ` Russell King @ 2005-12-14 5:50 ` Greg KH 2005-12-14 6:58 ` Pete Zaitcev 2005-12-14 23:26 ` Pete Zaitcev 1 sibling, 2 replies; 11+ messages in thread From: Greg KH @ 2005-12-14 5:50 UTC (permalink / raw) To: Pete Zaitcev; +Cc: linux-kernel On Mon, Dec 12, 2005 at 01:49:04PM -0800, Pete Zaitcev wrote: > Hi, Greg, > > When I plug a USB card reader with multiply LUNs, the following happens: > > [zaitcev@niphredil ~]$ ls -l /sys/devices/pci0000:00/0000:00:07.2/usb1/1-2/1-2:1.0 > total 0 > -r--r--r-- 1 root root 4096 Dec 12 12:47 bAlternateSetting > -r--r--r-- 1 root root 4096 Dec 12 12:46 bInterfaceClass > -r--r--r-- 1 root root 4096 Dec 12 12:46 bInterfaceNumber > -r--r--r-- 1 root root 4096 Dec 12 12:46 bInterfaceProtocol > -r--r--r-- 1 root root 4096 Dec 12 12:46 bInterfaceSubClass > lrwxrwxrwx 1 root root 0 Dec 12 12:47 block -> ../../../../../../block/ubd > lrwxrwxrwx 1 root root 0 Dec 12 12:47 block -> ../../../../../../block/ubd > lrwxrwxrwx 1 root root 0 Dec 12 12:47 block -> ../../../../../../block/ubd > lrwxrwxrwx 1 root root 0 Dec 12 12:47 block -> ../../../../../../block/ubd > -r--r--r-- 1 root root 4096 Dec 12 12:46 bNumEndpoints > lrwxrwxrwx 1 root root 0 Dec 12 12:46 bus -> ../../../../../../bus/usb > -r--r--r-- 1 root root 4096 Dec 12 12:47 diag > lrwxrwxrwx 1 root root 0 Dec 12 12:46 driver -> ../../../../../../bus/usb/drivers/ub > -r--r--r-- 1 root root 4096 Dec 12 12:46 modalias > drwxr-xr-x 2 root root 0 Dec 12 12:46 power > Do you have a suggestion about the fastest way to accomplish the same > effect with ub? Ick, you are right, sorry about this. We changed the class code to add the class device name to the symlink, because of this very problem. I forgot to convert the block code to do the same thing. Now, with the patch below my system looks like: $ ls -l /sys/block/uba/device/ total 0 -r--r--r-- 1 root root 4096 Dec 13 21:31 bAlternateSetting -r--r--r-- 1 root root 4096 Dec 13 21:31 bInterfaceClass -r--r--r-- 1 root root 4096 Dec 13 21:31 bInterfaceNumber -r--r--r-- 1 root root 4096 Dec 13 21:31 bInterfaceProtocol -r--r--r-- 1 root root 4096 Dec 13 21:31 bInterfaceSubClass -r--r--r-- 1 root root 4096 Dec 13 21:31 bNumEndpoints lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:uba -> ../../../../../../block/uba lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubb -> ../../../../../../block/ubb lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubc -> ../../../../../../block/ubc lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubd -> ../../../../../../block/ubd lrwxrwxrwx 1 root root 0 Dec 13 13:28 bus -> ../../../../../../bus/usb -r--r--r-- 1 root root 4096 Dec 13 21:31 diag lrwxrwxrwx 1 root root 0 Dec 13 21:31 driver -> ../../../../../../bus/usb/drivers/ub drwxr-xr-x 2 root root 0 Dec 13 21:31 ep_02 drwxr-xr-x 2 root root 0 Dec 13 21:31 ep_82 -r--r--r-- 1 root root 4096 Dec 13 21:31 modalias drwxr-xr-x 2 root root 0 Dec 13 21:28 power --w------- 1 root root 4096 Dec 13 21:28 uevent This will also fix the problem for floppy devices, like Russell pointed out. Look good to you? thanks, greg k-h ----------------- >From foo@baz.org Tue Dec 13 15:20:15 2005 Date: Tue, 13 Dec 2005 15:17:34 -0800 From: Greg Kroah-Hartman <gregkh@suse.de> Subject: Driver core: Make block devices create the proper symlink name Block devices need to add the block device name to the symlink they put in the device directory, otherwise multiple symlinks of the same name can be created. This matches the class system, which works the same way, we just forgot to convert block at the same time. Cc: Pete Zaitcev <zaitcev@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> --- fs/partitions/check.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) --- gregkh-2.6.orig/fs/partitions/check.c +++ gregkh-2.6/fs/partitions/check.c @@ -325,12 +325,31 @@ void add_partition(struct gendisk *disk, disk->part[part-1] = p; } +static char *make_block_name(struct gendisk *disk) +{ + char *name; + static char *block_str = "block:"; + int size; + + size = strlen(block_str) + strlen(disk->disk_name) + 1; + name = kmalloc(size, GFP_KERNEL); + if (!name) + return NULL; + strcpy(name, block_str); + strcat(name, disk->disk_name); + return name; +} + static void disk_sysfs_symlinks(struct gendisk *disk) { struct device *target = get_device(disk->driverfs_dev); if (target) { + char *disk_name = make_block_name(disk); sysfs_create_link(&disk->kobj,&target->kobj,"device"); - sysfs_create_link(&target->kobj,&disk->kobj,"block"); + if (disk_name) { + sysfs_create_link(&target->kobj,&disk->kobj,disk_name); + kfree(disk_name); + } } } @@ -444,8 +463,12 @@ void del_gendisk(struct gendisk *disk) disk->stamp = 0; if (disk->driverfs_dev) { + char *disk_name = make_block_name(disk); sysfs_remove_link(&disk->kobj, "device"); - sysfs_remove_link(&disk->driverfs_dev->kobj, "block"); + if (disk_name) { + sysfs_remove_link(&disk->driverfs_dev->kobj, disk_name); + kfree(disk_name); + } put_device(disk->driverfs_dev); } ndevfs_remove(kobject_name(&disk->kobj)); ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-14 5:50 ` Greg KH @ 2005-12-14 6:58 ` Pete Zaitcev 2005-12-14 23:26 ` Pete Zaitcev 1 sibling, 0 replies; 11+ messages in thread From: Pete Zaitcev @ 2005-12-14 6:58 UTC (permalink / raw) To: Greg KH; +Cc: linux-kernel On Tue, 13 Dec 2005 21:50:19 -0800, Greg KH <greg@kroah.com> wrote: > -r--r--r-- 1 root root 4096 Dec 13 21:31 bNumEndpoints > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:uba -> ../../../../../../block/uba > This will also fix the problem for floppy devices, like Russell pointed > out. Look good to you? Poking installer people for an opinion now (they filed the bug). -- Pete ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-14 5:50 ` Greg KH 2005-12-14 6:58 ` Pete Zaitcev @ 2005-12-14 23:26 ` Pete Zaitcev 2005-12-14 23:42 ` Greg KH 1 sibling, 1 reply; 11+ messages in thread From: Pete Zaitcev @ 2005-12-14 23:26 UTC (permalink / raw) To: Greg KH; +Cc: linux-kernel, katzj, zaitcev On Tue, 13 Dec 2005 21:50:19 -0800, Greg KH <greg@kroah.com> wrote: > $ ls -l /sys/block/uba/device/ > -r--r--r-- 1 root root 4096 Dec 13 21:31 bNumEndpoints > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:uba -> ../../../../../../block/uba > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubb -> ../../../../../../block/ubb > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubc -> ../../../../../../block/ubc > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubd -> ../../../../../../block/ubd Greg, Jeremy is not happy about this. > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=175563 > ------- Additional Comments From katzj@redhat.com 2005-12-14 18:05 EST ------- > Actually, this is problematic. It makes it so that the single device directory > corresponds to more than one device which we can't handle with kudzu :-( Sorry, -- Pete ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-14 23:26 ` Pete Zaitcev @ 2005-12-14 23:42 ` Greg KH 2005-12-15 0:10 ` Pete Zaitcev 2005-12-15 4:47 ` Jeremy Katz 0 siblings, 2 replies; 11+ messages in thread From: Greg KH @ 2005-12-14 23:42 UTC (permalink / raw) To: Pete Zaitcev; +Cc: linux-kernel, katzj On Wed, Dec 14, 2005 at 03:26:15PM -0800, Pete Zaitcev wrote: > On Tue, 13 Dec 2005 21:50:19 -0800, Greg KH <greg@kroah.com> wrote: > > > $ ls -l /sys/block/uba/device/ > > -r--r--r-- 1 root root 4096 Dec 13 21:31 bNumEndpoints > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:uba -> ../../../../../../block/uba > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubb -> ../../../../../../block/ubb > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubc -> ../../../../../../block/ubc > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubd -> ../../../../../../block/ubd > > Greg, Jeremy is not happy about this. > > > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=175563 > > ------- Additional Comments From katzj@redhat.com 2005-12-14 18:05 EST ------- > > Actually, this is problematic. It makes it so that the single device directory > > corresponds to more than one device which we can't handle with kudzu :-( Well, how do you handle it for class devices then? And if this isn't acceptable, what would be? Just because kudzu is messed up... :) thanks, greg k-h ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-14 23:42 ` Greg KH @ 2005-12-15 0:10 ` Pete Zaitcev 2005-12-15 0:44 ` Greg KH 2005-12-15 4:47 ` Jeremy Katz 1 sibling, 1 reply; 11+ messages in thread From: Pete Zaitcev @ 2005-12-15 0:10 UTC (permalink / raw) To: Greg KH; +Cc: linux-kernel, katzj, zaitcev On Wed, 14 Dec 2005 15:42:55 -0800, Greg KH <greg@kroah.com> wrote: > And if this isn't acceptable, what would be? > > Just because kudzu is messed up... :) I thought maybe creating some struct kobject by hand for every LUN. This is undesirable mainly because I do not trust myself with handling struct kobject at all (currently I only use block device API and so I blame Jens every time there's a problem :-)). But if Jeremy cannot work around it, I would have to think about it - maybe as a Fedora-specific patch. -- Pete ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-15 0:10 ` Pete Zaitcev @ 2005-12-15 0:44 ` Greg KH 2005-12-15 2:47 ` Bill Nottingham 0 siblings, 1 reply; 11+ messages in thread From: Greg KH @ 2005-12-15 0:44 UTC (permalink / raw) To: Pete Zaitcev; +Cc: linux-kernel, katzj On Wed, Dec 14, 2005 at 04:10:18PM -0800, Pete Zaitcev wrote: > On Wed, 14 Dec 2005 15:42:55 -0800, Greg KH <greg@kroah.com> wrote: > > > And if this isn't acceptable, what would be? > > > > Just because kudzu is messed up... :) > > I thought maybe creating some struct kobject by hand for every LUN. > This is undesirable mainly because I do not trust myself with handling > struct kobject at all (currently I only use block device API and so I > blame Jens every time there's a problem :-)). But if Jeremy cannot > work around it, I would have to think about it - maybe as a Fedora-specific > patch. I don't understand, what exactly would you like to see in the block device's device directory? With this patch, we correctly point back to all of the different block devices controlled by this device. I'm curious as to why kudzu even cares about this? And, how does it handle things like mult-port serial devices, which have all of the multiple class device symlinks in one single device directory, just like this. thanks, greg k-h ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-15 0:44 ` Greg KH @ 2005-12-15 2:47 ` Bill Nottingham 0 siblings, 0 replies; 11+ messages in thread From: Bill Nottingham @ 2005-12-15 2:47 UTC (permalink / raw) To: Greg KH; +Cc: Pete Zaitcev, linux-kernel, katzj Greg KH (greg@kroah.com) said: > I don't understand, what exactly would you like to see in the block > device's device directory? With this patch, we correctly point back to > all of the different block devices controlled by this device. > > I'm curious as to why kudzu even cares about this? Actually, it shouldn't be a problem. > And, how does it handle things like mult-port serial devices, which have > all of the multiple class device symlinks in one single device > directory, just like this. Ignores them entirely, of course. (kudzu at this point is used solely in the installer.) Bill ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-14 23:42 ` Greg KH 2005-12-15 0:10 ` Pete Zaitcev @ 2005-12-15 4:47 ` Jeremy Katz 2005-12-15 16:53 ` Greg KH 1 sibling, 1 reply; 11+ messages in thread From: Jeremy Katz @ 2005-12-15 4:47 UTC (permalink / raw) To: Greg KH; +Cc: Pete Zaitcev, linux-kernel On Wed, 2005-12-14 at 15:42 -0800, Greg KH wrote: > On Wed, Dec 14, 2005 at 03:26:15PM -0800, Pete Zaitcev wrote: > > On Tue, 13 Dec 2005 21:50:19 -0800, Greg KH <greg@kroah.com> wrote: > > > $ ls -l /sys/block/uba/device/ > > > -r--r--r-- 1 root root 4096 Dec 13 21:31 bNumEndpoints > > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:uba -> ../../../../../../block/uba > > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubb -> ../../../../../../block/ubb > > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubc -> ../../../../../../block/ubc > > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubd -> ../../../../../../block/ubd > > > > Greg, Jeremy is not happy about this. > > > > > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=175563 > > > ------- Additional Comments From katzj@redhat.com 2005-12-14 18:05 EST ------- > > > Actually, this is problematic. It makes it so that the single device directory > > > corresponds to more than one device which we can't handle with kudzu :-( > > Well, how do you handle it for class devices then? We don't have any where we need to handle it at present. > And if this isn't acceptable, what would be? By going this route, it really feels like you're hacking around your own rule of a single value per file :-) Except that instead of having a file that I read five values from, it's five files with naming heuristics to get five values. Which is, in a lot of ways, worse. I'd much rather see the fact that there are multiple devices be handled by having each device with its own unique directory. This then keeps all of the abstractions which currently exist. Jeremy ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: "block" symlink in sysfs for a multifunction device 2005-12-15 4:47 ` Jeremy Katz @ 2005-12-15 16:53 ` Greg KH 0 siblings, 0 replies; 11+ messages in thread From: Greg KH @ 2005-12-15 16:53 UTC (permalink / raw) To: Jeremy Katz; +Cc: Pete Zaitcev, linux-kernel On Wed, Dec 14, 2005 at 11:47:35PM -0500, Jeremy Katz wrote: > On Wed, 2005-12-14 at 15:42 -0800, Greg KH wrote: > > On Wed, Dec 14, 2005 at 03:26:15PM -0800, Pete Zaitcev wrote: > > > On Tue, 13 Dec 2005 21:50:19 -0800, Greg KH <greg@kroah.com> wrote: > > > > $ ls -l /sys/block/uba/device/ > > > > -r--r--r-- 1 root root 4096 Dec 13 21:31 bNumEndpoints > > > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:uba -> ../../../../../../block/uba > > > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubb -> ../../../../../../block/ubb > > > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubc -> ../../../../../../block/ubc > > > > lrwxrwxrwx 1 root root 0 Dec 13 21:31 block:ubd -> ../../../../../../block/ubd > > > > > > Greg, Jeremy is not happy about this. > > > > > > > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=175563 > > > > ------- Additional Comments From katzj@redhat.com 2005-12-14 18:05 EST ------- > > > > Actually, this is problematic. It makes it so that the single device directory > > > > corresponds to more than one device which we can't handle with kudzu :-( > > > > Well, how do you handle it for class devices then? > > We don't have any where we need to handle it at present. > > > And if this isn't acceptable, what would be? > > By going this route, it really feels like you're hacking around your own > rule of a single value per file :-) Except that instead of having a > file that I read five values from, it's five files with naming > heuristics to get five values. Which is, in a lot of ways, worse. What? These are symlinks, not files. Why would you want to read the name of the block device from a file and then go have to look that location up, instead of just following the symlink? > I'd much rather see the fact that there are multiple devices be handled > by having each device with its own unique directory. This then keeps > all of the abstractions which currently exist. Those devices do have their own unique directory. Look at the pointer above :) The point here is that multiple class devices and block devices can bind to a single "real device" in the system, and we need to handle that representation properly. We have had the symlink for a while now, and I just forgot to put the proper name on the block device one, to match up with the class device naming. thanks, greg k-h ^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2005-12-15 16:54 UTC | newest] Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2005-12-12 21:49 "block" symlink in sysfs for a multifunction device Pete Zaitcev 2005-12-12 21:53 ` Russell King 2005-12-14 5:50 ` Greg KH 2005-12-14 6:58 ` Pete Zaitcev 2005-12-14 23:26 ` Pete Zaitcev 2005-12-14 23:42 ` Greg KH 2005-12-15 0:10 ` Pete Zaitcev 2005-12-15 0:44 ` Greg KH 2005-12-15 2:47 ` Bill Nottingham 2005-12-15 4:47 ` Jeremy Katz 2005-12-15 16:53 ` Greg KH
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