diff options
| author | Amir Goldstein <amir73il@gmail.com> | 2023-04-02 21:56:49 +0300 |
|---|---|---|
| committer | Amir Goldstein <amir73il@gmail.com> | 2023-06-19 14:01:14 +0300 |
| commit | 416656447864ef0fc2430525499f52a4a370a0ab (patch) | |
| tree | a846326abea45b0377037ab32220364df3d98702 /fs/overlayfs/super.c | |
| parent | 2b21da920866ad20b5e3119f3b8d2267774b7b0a (diff) | |
ovl: prepare for lazy lookup of lowerdata inode
Make the code handle the case of numlower > 1 and missing lowerdata
dentry gracefully.
Missing lowerdata dentry is an indication for lazy lookup of lowerdata
and in that case the lowerdata_redirect path is stored in ovl_inode.
Following commits will defer lookup and perform the lazy lookup on
access.
Reviewed-by: Alexander Larsson <alexl@redhat.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs/overlayfs/super.c')
| -rw-r--r-- | fs/overlayfs/super.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 9de02ca2387e..f3e5b43c4106 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -81,6 +81,14 @@ static struct dentry *ovl_d_real(struct dentry *dentry, if (real && !inode && ovl_has_upperdata(d_inode(dentry))) return real; + /* + * XXX: We may need lazy lookup of lowerdata for !inode case to return + * the real lowerdata dentry. The only current caller of d_real() with + * NULL inode is d_real_inode() from trace_uprobe and this caller is + * likely going to be followed reading from the file, before placing + * uprobes on offset within the file, so lowerdata should be available + * when setting the uprobe. + */ lower = ovl_dentry_lowerdata(dentry); if (!lower) goto bug; @@ -103,6 +111,9 @@ static int ovl_revalidate_real(struct dentry *d, unsigned int flags, bool weak) { int ret = 1; + if (!d) + return 1; + if (weak) { if (d->d_flags & DCACHE_OP_WEAK_REVALIDATE) ret = d->d_op->d_weak_revalidate(d, flags); |