On 1/15/25 17:32, Luis Henriques wrote: > Currently userspace is able to notify the kernel to invalidate the cache > for an inode. This means that, if all the inodes in a filesystem need to > be invalidated, then userspace needs to iterate through all of them and do > this kernel notification separately. > > This patch adds a new option that allows userspace to invalidate all the > inodes with a single notification operation. In addition to invalidate all > the inodes, it also shrinks the superblock dcache. Out of interest, what is the use case? > > Signed-off-by: Luis Henriques <luis@xxxxxxxxxx> > --- > Just an additional note that this patch could eventually be simplified if > Dave Chinner patch to iterate through the superblock inodes[1] is merged. > > [1] https://lore.kernel.org/r/20241002014017.3801899-3-david@xxxxxxxxxxxxx > > fs/fuse/inode.c | 53 +++++++++++++++++++++++++++++++++++++++ > include/uapi/linux/fuse.h | 3 +++ > 2 files changed, 56 insertions(+) > > diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c > index 3ce4f4e81d09..1fd9a5f303da 100644 > --- a/fs/fuse/inode.c > +++ b/fs/fuse/inode.c > @@ -546,6 +546,56 @@ struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid, > return NULL; > } > > +static int fuse_reverse_inval_all(struct fuse_conn *fc) > +{ > + struct fuse_mount *fm; > + struct super_block *sb; > + struct inode *inode, *old_inode = NULL; > + struct fuse_inode *fi; > + > + inode = fuse_ilookup(fc, FUSE_ROOT_ID, NULL); > + if (!inode) > + return -ENOENT; > + > + fm = get_fuse_mount(inode); > + iput(inode); > + if (!fm) > + return -ENOENT; > + sb = fm->sb; > + > + spin_lock(&sb->s_inode_list_lock); > + list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { Maybe list_for_each_entry_safe() and then you can iput(inode) before the next iteration? > + spin_lock(&inode->i_lock); > + if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || > + !atomic_read(&inode->i_count)) { > + spin_unlock(&inode->i_lock); > + continue; > + } > + > + __iget(inode); > + spin_unlock(&inode->i_lock); > + spin_unlock(&sb->s_inode_list_lock); > + iput(old_inode); > + > + fi = get_fuse_inode(inode); > + spin_lock(&fi->lock); > + fi->attr_version = atomic64_inc_return(&fm->fc->attr_version); > + spin_unlock(&fi->lock); > + fuse_invalidate_attr(inode); > + forget_all_cached_acls(inode); > + > + old_inode = inode; > + cond_resched(); > + spin_lock(&sb->s_inode_list_lock); > + } > + spin_unlock(&sb->s_inode_list_lock); > + iput(old_inode); Thanks, Bernd
