kernel/linux.git/fs/autofs/root.c, branch linux-6.0.y

autofs: add comment about autofs_mountpoint_changed()

2022-07-18T00:31:42+00:00

The function autofs_mountpoint_changed() is unusual, add a comment about two cases for which it is needed. Link: https://lkml.kernel.org/r/165724459804.30914.10974834416046555127.stgit@donald.themaw.net Signed-off-by: Ian Kent Cc: Al Viro Cc: David Howells Cc: Miklos Szeredi Signed-off-by: Andrew Morton

autofs: use dentry info count instead of simple_empty()

2022-07-18T00:31:42+00:00

The dentry info. field count is used to check if a dentry is in use during expire. But, to be used for this the count field must account for the presence of child dentries in a directory dentry. Therefore it can also be used to check for an empty directory dentry which can be done without having to to take an additional lock or account for the presence of a readdir cursor dentry as is done by simple_empty(). Link: https://lkml.kernel.org/r/165724459238.30914.1504611159945950108.stgit@donald.themaw.net Signed-off-by: Ian Kent Cc: Al Viro Cc: David Howells Cc: Miklos Szeredi Signed-off-by: Andrew Morton

autofs: make dentry info count consistent

2022-07-18T00:31:42+00:00

If an autofs dentry is a mount root directory there's no ->mkdir() call to set its count to one. To make the dentry info count consistent for all autofs dentries set count to one when the dentry info struct is allocated. Link: https://lkml.kernel.org/r/165724458671.30914.2902424437132835325.stgit@donald.themaw.net Signed-off-by: Ian Kent Cc: Al Viro Cc: David Howells Cc: Miklos Szeredi Signed-off-by: Andrew Morton

autofs: use inode permission method for write access

2022-07-18T00:31:42+00:00

Patch series "autofs: misc patches". This series contains several patches that resulted mostly from comments made by Al Viro (quite a long time ago now). This patch (of 5): Eliminate some code duplication from mkdir/rmdir/symlink/unlink methods by using the inode operation .permission(). Link: https://lkml.kernel.org/r/165724445154.30914.10970894936827635879.stgit@donald.themaw.net Link: https://lkml.kernel.org/r/165724458096.30914.13499431569758625806.stgit@donald.themaw.net Signed-off-by: Ian Kent Cc: Al Viro Cc: David Howells Cc: Miklos Szeredi Signed-off-by: Andrew Morton

fs: make helpers idmap mount aware

2021-01-24T13:27:20+00:00

Extend some inode methods with an additional user namespace argument. A filesystem that is aware of idmapped mounts will receive the user namespace the mount has been marked with. This can be used for additional permission checking and also to enable filesystems to translate between uids and gids if they need to. We have implemented all relevant helpers in earlier patches. As requested we simply extend the exisiting inode method instead of introducing new ones. This is a little more code churn but it's mostly mechanical and doesnt't leave us with additional inode methods. Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner

autofs: don't bother with atomics for ino->count

2019-09-18T03:31:27+00:00

All writers are serialized on inode->i_rwsem. So are the readers outside of expire.c. And the readers in expire.c are in the code that really doesn't care about narrow races - it's looking for expiry candidates and its callers have to cope with the possibility of a good candidate becoming busy right under them. No point bothering with atomic operations - just use int and mark the non-serialized readers with READ_ONCE(). Signed-off-by: Al Viro

autofs_dir_rmdir(): check ino->count for deciding whether it's empty...

2019-09-18T03:28:08+00:00

Signed-off-by: Al Viro

autofs: get rid of pointless checks around ->count handling

2019-09-18T03:23:08+00:00

* IS_ROOT can't be true for unlink or rmdir victim * any positive autofs dentry has non-NULL autofs_dentry_ino() * autofs symlink can't have ->count other than 1 * autofs empty directory can't have ->count other than 1 Signed-off-by: Al Viro

autofs_clear_leaf_automount_flags(): use ino->count instead of ->d_subdirs

2019-09-18T02:16:58+00:00

We want to find out if the parent will become empty after we remove the victim of rmdir(). Checking if the victim is the only element of parent's ->d_subdirs is completely wrong - e.g. opening the parent will end up with a cursor added to its ->d_parent and fooling the check. We do maintain ino->count - 0 for anything removed, 1 + number of children for anything live. Which gives us precisely what we need for that check... Signed-off-by: Al Viro

autofs_lookup(): hold ->d_lock over playing with ->d_flags

2019-07-27T14:03:14+00:00

... as well as setting ->d_fsdata, etc. Make all of that atomic. Signed-off-by: Al Viro