On Wed, 2021-12-22 at 23:25 +0000, David Howells wrote: > Use an inode flag, S_KERNEL_FILE, to mark that a backing file is in use by > the kernel to prevent cachefiles or other kernel services from interfering > with that file. > > Using S_SWAPFILE instead isn't really viable as that has other effects in > the I/O paths. > > Signed-off-by: David Howells <dhowells@xxxxxxxxxx> > cc: linux-cachefs@xxxxxxxxxx > Link: https://lore.kernel.org/r/163819642273.215744.6414248677118690672.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v1 > Link: https://lore.kernel.org/r/163906943215.143852.16972351425323967014.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v2 > Link: https://lore.kernel.org/r/163967154118.1823006.13227551961786743991.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v3 > --- > > fs/cachefiles/internal.h | 2 ++ > fs/cachefiles/namei.c | 35 +++++++++++++++++++++++++++++++++++ > 2 files changed, 37 insertions(+) > > diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h > index 01071e7a7c02..7c67a70a3dff 100644 > --- a/fs/cachefiles/internal.h > +++ b/fs/cachefiles/internal.h > @@ -187,6 +187,8 @@ extern struct kmem_cache *cachefiles_object_jar; > /* > * namei.c > */ > +extern void cachefiles_unmark_inode_in_use(struct cachefiles_object *object, > + struct file *file); > extern struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, > struct dentry *dir, > const char *name, > diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c > index 11a33209ab5f..db60a671c3fc 100644 > --- a/fs/cachefiles/namei.c > +++ b/fs/cachefiles/namei.c > @@ -31,6 +31,18 @@ static bool __cachefiles_mark_inode_in_use(struct cachefiles_object *object, > return can_use; > } > > +static bool cachefiles_mark_inode_in_use(struct cachefiles_object *object, > + struct dentry *dentry) > +{ > + struct inode *inode = d_backing_inode(dentry); > + bool can_use; > + > + inode_lock(inode); > + can_use = __cachefiles_mark_inode_in_use(object, dentry); > + inode_unlock(inode); > + return can_use; > +} > + > /* > * Unmark a backing inode. The caller must hold the inode lock. > */ > @@ -43,6 +55,29 @@ static void __cachefiles_unmark_inode_in_use(struct cachefiles_object *object, > trace_cachefiles_mark_inactive(object, inode); > } > > +/* > + * Unmark a backing inode and tell cachefilesd that there's something that can > + * be culled. > + */ > +void cachefiles_unmark_inode_in_use(struct cachefiles_object *object, > + struct file *file) > +{ > + struct cachefiles_cache *cache = object->volume->cache; > + struct inode *inode = file_inode(file); > + > + if (inode) { > + inode_lock(inode); > + __cachefiles_unmark_inode_in_use(object, file->f_path.dentry); > + inode_unlock(inode); > + > + if (!test_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags)) { > + atomic_long_add(inode->i_blocks, &cache->b_released); > + if (atomic_inc_return(&cache->f_released)) > + cachefiles_state_changed(cache); > + } > + } > +} > + > /* > * get a subdirectory > */ > > Probably, this patch should be merged with #38. The commit logs are the same, and they are at least somewhat related. -- Jeff Layton <jlayton@xxxxxxxxxx>
