Fix outstanding .zfs/snapshot issues #3718
Conversation
|
It's meant to be used instead of #3344, and it addresses most of the remaining issues I'm aware of. |
|
seems to work for me |
|
I am testing this patch applied on tag 0.6.4.2 , one thing I noticed was that it does not apply cleanly due to change in function EDIT: above change aside, this patch works well when applied on top of 0.6.4.2, on vanilla kernel 4.0.9 (ArchLinux, my own kernel build). I can enumerate and access snapshots, no problems when trying to access non-existing ones (as was the case in #3344), no problems explicitly unmounting them, no problems with automatic unmounting. The files look as expected inside mounted snapshots. |
|
@Bronek @prometheanfire thanks for the quick turn around on the testing. |
There's no metadata to write to disk for ctldir inodes. So we check if a inode belongs to the ctldir in zpl_commit_metadata, and returns immediately if it is. Signed-off-by: Andrey Vesnovaty <andrey.vesnovaty@gmail.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue openzfs#2797
|
Refreshed against master, some minor compatibility code added for 2.6.37 and earlier kernels. Aside from that the patch remains the same and has been holding up well to stress testing. |
|
Accessing files and the automatic (un)mounting works for me on a 4.0.5 kernel with the master branch of spl and the master + this patch of zfs. Thanks! I did notice the following, but I'm not sure if it's related
|
Re-factor the .zfs/snapshot auto-mouting code to take in to account changes made to the upstream kernels. And to lay the groundwork for enabling access to .zfs snapshots via NFS clients. This patch makes the following core improvements. * All actively auto-mounted snapshots are now tracked in two global trees which are indexed by snapshot name and objset id respectively. This allows for fast lookups of any auto-mounted snapshot regardless without needing access to the parent dataset. * Snapshot entries are added to the tree in zfsctl_snapshot_mount(). However, they are now removed from the tree in the context of the unmount process. This eliminates the need complicated error logic in zfsctl_snapshot_unmount() to handle unmount failures. * References are now taken on the snapshot entries in the tree to ensure they always remain valid while a task is outstanding. * The MNT_SHRINKABLE flag is set on the snapshot vfsmount_t right after the auto-mount succeeds. This allows to kernel to unmount idle auto-mounted snapshots if needed removing the need for the zfsctl_unmount_snapshots() function. * Snapshots in active use will not be automatically unmounted. As long as at least one dentry is revalidated every zfs_expire_snapshot/2 seconds the auto-unmount expiration timer will be extended. * Commit torvalds/linux@bafc9b7 caused snapshots auto-mounted by ZFS to be immediately unmounted when the dentry was revalidated. This was a consequence of ZFS invaliding all snapdir dentries to ensure that negative dentries didn't mask new snapshots. This patch modifies the behavior such that only negative dentries are invalidated. This solves the issue and may result in a performance improvement. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes openzfs#3589 Closes openzfs#3344 Closes openzfs#3295 Closes openzfs#3257 Closes openzfs#3243 Closes openzfs#3030 Closes openzfs#2841
| argv[2] = kmem_asprintf(SET_MOUNT_CMD, full_name, full_path); | ||
| error = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC); | ||
| strfree(argv[2]); | ||
| if (error && !(error & MOUNT_BUSY << 8)) { | ||
| printk("ZFS: Unable to automount %s at %s: %d\n", | ||
| full_name, full_path, error); | ||
| cmn_err(CE_WARN, "Unable to automount %s/%s: %d\n", |
There was a problem hiding this comment.
Yes, I'll remove it.
|
This makes snapshots directory listing work on Ubuntu stock kernel 3.19.0-26-generic, yay! Previously, kernel panic with snapdir=visible always. |
|
@janlam7 I saw this in my testing as well but I haven't had a chance to look in to why only a single auto-mount is triggered by a |
No description provided.