Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-17 Thread Goffredo Baroncelli
On 2015-06-15 19:38, Lennart Poettering wrote: On Mon, 15.06.15 19:23, Goffredo Baroncelli (kreij...@inwind.it) wrote: On 2015-06-15 12:46, Lennart Poettering wrote: On Sat, 13.06.15 17:09, Goffredo Baroncelli (kreij...@libero.it) wrote: Further, the problem will be more intense in this eg.

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-17 Thread Andrei Borzenkov
В Wed, 17 Jun 2015 23:02:02 +0200 Lennart Poettering lenn...@poettering.net пишет: On Wed, 17.06.15 21:10, Goffredo Baroncelli (kreij...@libero.it) wrote: Well, /bin/mount is not a daemon, and it should not be one. My helper is not a deamon; you was correct the first time: it blocks

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-17 Thread Lennart Poettering
On Wed, 17.06.15 21:10, Goffredo Baroncelli (kreij...@libero.it) wrote: Well, /bin/mount is not a daemon, and it should not be one. My helper is not a deamon; you was correct the first time: it blocks until all needed/enough devices are appeared. Anyway this should not be different from

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-15 Thread Lennart Poettering
On Sat, 13.06.15 17:35, Anand Jain (anand.j...@oracle.com) wrote: Are there any other users? - If the the device in the argument is already mounted, can it straightaway return 0 (ready) ? (as of now it would again independently read the SB determine total_devices and

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-15 Thread Lennart Poettering
On Fri, 12.06.15 21:16, Anand Jain (anand.j...@oracle.com) wrote: BTRFS_IOC_DEVICES_READY is to check if all the required devices are known by the btrfs kernel, so that admin/system-application could mount the FS. It is checked against a device in the argument. However the actual

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-15 Thread Lennart Poettering
On Sat, 13.06.15 17:09, Goffredo Baroncelli (kreij...@libero.it) wrote: Further, the problem will be more intense in this eg. if you use dd and copy device A to device B. After you mount device A, by just providing device B in the above two commands you could let kernel update the device

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-15 Thread David Sterba
On Fri, Jun 12, 2015 at 09:16:30PM +0800, Anand Jain wrote: BTRFS_IOC_DEVICES_READY is to check if all the required devices are known by the btrfs kernel, so that admin/system-application could mount the FS. It is checked against a device in the argument. However the actual implementation is

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-15 Thread Lennart Poettering
On Mon, 15.06.15 19:23, Goffredo Baroncelli (kreij...@inwind.it) wrote: On 2015-06-15 12:46, Lennart Poettering wrote: On Sat, 13.06.15 17:09, Goffredo Baroncelli (kreij...@libero.it) wrote: Further, the problem will be more intense in this eg. if you use dd and copy device A to device

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-14 Thread Goffredo Baroncelli
On 2015-06-14 06:05, Duncan wrote: Goffredo Baroncelli posted on Sat, 13 Jun 2015 17:09:19 +0200 as excerpted: My attempt followed a different idea: the mount helper waits the devices if needed, or if it is the case it mounts the filesystem in degraded mode. All devices are passed as mount

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-13 Thread Duncan
Goffredo Baroncelli posted on Sat, 13 Jun 2015 17:09:19 +0200 as excerpted: My attempt followed a different idea: the mount helper waits the devices if needed, or if it is the case it mounts the filesystem in degraded mode. All devices are passed as mount arguments (--device=/dev/sdX), there

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-13 Thread Andrei Borzenkov
В Sat, 13 Jun 2015 17:35:53 +0800 Anand Jain anand.j...@oracle.com пишет: Thanks for your reply Andrei and Goffredo. more below... On 06/13/2015 04:08 AM, Goffredo Baroncelli wrote: On 2015-06-12 20:04, Andrei Borzenkov wrote: В Fri, 12 Jun 2015 21:16:30 +0800 Anand Jain

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-13 Thread Goffredo Baroncelli
On 2015-06-13 11:35, Anand Jain wrote: Thanks for your reply Andrei and Goffredo. more below... On 06/13/2015 04:08 AM, Goffredo Baroncelli wrote: On 2015-06-12 20:04, Andrei Borzenkov wrote: В Fri, 12 Jun 2015 21:16:30 +0800 Anand Jain anand.j...@oracle.com пишет:

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-13 Thread Anand Jain
Thanks for your reply Andrei and Goffredo. more below... On 06/13/2015 04:08 AM, Goffredo Baroncelli wrote: On 2015-06-12 20:04, Andrei Borzenkov wrote: В Fri, 12 Jun 2015 21:16:30 +0800 Anand Jain anand.j...@oracle.com пишет: BTRFS_IOC_DEVICES_READY is to check if all the required

[systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-12 Thread Anand Jain
BTRFS_IOC_DEVICES_READY is to check if all the required devices are known by the btrfs kernel, so that admin/system-application could mount the FS. It is checked against a device in the argument. However the actual implementation is bit more than just that, in the way that it would also scan

Re: [systemd-devel] [survey] BTRFS_IOC_DEVICES_READY return status

2015-06-12 Thread Andrei Borzenkov
В Fri, 12 Jun 2015 21:16:30 +0800 Anand Jain anand.j...@oracle.com пишет: BTRFS_IOC_DEVICES_READY is to check if all the required devices are known by the btrfs kernel, so that admin/system-application could mount the FS. It is checked against a device in the argument. However the