diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 2d6251a4caaff99537485aa1c0dcf51bb15871d5..b0d42ece4d7ccc470534576817278f8cdff0f08c 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -99,13 +99,13 @@ static int ovl_map_dev_ino(struct dentry *dentry, struct kstat *stat, int fsid)
* This way all overlay inode numbers are unique and use the
* overlay st_dev.
*/
- if (unlikely(stat->ino >> xinoshift)) {
- pr_warn_ratelimited("inode number too big (%pd2, ino=%llu, xinobits=%d)\n",
- dentry, stat->ino, xinobits);
- } else {
+ if (likely(!(stat->ino >> xinoshift))) {
stat->ino |= ((u64)fsid) << (xinoshift + 1);
stat->dev = dentry->d_sb->s_dev;
return 0;
+ } else if (ovl_xino_warn(dentry->d_sb)) {
+ pr_warn_ratelimited("inode number too big (%pd2, ino=%llu, xinobits=%d)\n",
+ dentry, stat->ino, xinobits);
}
}
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index e81fea86139e6ea603252da61f9bf48179a4e9e7..e6f3670146ed1d1c4a64ef580f7818e1f14f6ba8 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -48,6 +48,12 @@ enum ovl_entry_flag {
OVL_E_CONNECTED,
};
+enum {
+ OVL_XINO_OFF,
+ OVL_XINO_AUTO,
+ OVL_XINO_ON,
+};
+
/*
* The tuple (fh,uuid) is a universal unique identifier for a copy up origin,
* where:
@@ -301,6 +307,16 @@ static inline bool ovl_is_impuredir(struct dentry *dentry)
return ovl_check_dir_xattr(dentry, OVL_XATTR_IMPURE);
}
+/*
+ * With xino=auto, we do best effort to keep all inodes on same st_dev and
+ * d_ino consistent with st_ino.
+ * With xino=on, we do the same effort but we warn if we failed.
+ */
+static inline bool ovl_xino_warn(struct super_block *sb)
+{
+ return OVL_FS(sb)->config.xino == OVL_XINO_ON;
+}
+
/* All layers on same fs? */
static inline bool ovl_same_fs(struct super_block *sb)
{
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 6325dcc4c48bb996315936b933feed174dc4dbac..e452ff7d583d251143fa98feefe05d53eb921570 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -438,13 +438,15 @@ static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry)
/* Map inode number to lower fs unique range */
static u64 ovl_remap_lower_ino(u64 ino, int xinobits, int fsid,
- const char *name, int namelen)
+ const char *name, int namelen, bool warn)
{
unsigned int xinoshift = 64 - xinobits;
if (unlikely(ino >> xinoshift)) {
- pr_warn_ratelimited("d_ino too big (%.*s, ino=%llu, xinobits=%d)\n",
- namelen, name, ino, xinobits);
+ if (warn) {
+ pr_warn_ratelimited("d_ino too big (%.*s, ino=%llu, xinobits=%d)\n",
+ namelen, name, ino, xinobits);
+ }
return ino;
}
@@ -521,7 +523,8 @@ static int ovl_cache_update_ino(struct path *path, struct ovl_cache_entry *p)
} else if (xinobits && !OVL_TYPE_UPPER(type)) {
ino = ovl_remap_lower_ino(ino, xinobits,
ovl_layer_lower(this)->fsid,
- p->name, p->len);
+ p->name, p->len,
+ ovl_xino_warn(dir->d_sb));
}
out:
@@ -651,6 +654,7 @@ struct ovl_readdir_translate {
u64 parent_ino;
int fsid;
int xinobits;
+ bool xinowarn;
};
static int ovl_fill_real(struct dir_context *ctx, const char *name,
@@ -671,7 +675,7 @@ static int ovl_fill_real(struct dir_context *ctx, const char *name,
ino = p->ino;
} else if (rdt->xinobits) {
ino = ovl_remap_lower_ino(ino, rdt->xinobits, rdt->fsid,
- name, namelen);
+ name, namelen, rdt->xinowarn);
}
return orig_ctx->actor(orig_ctx, name, namelen, offset, ino, d_type);
@@ -702,6 +706,7 @@ static int ovl_iterate_real(struct file *file, struct dir_context *ctx)
.ctx.actor = ovl_fill_real,
.orig_ctx = ctx,
.xinobits = ovl_xino_bits(dir->d_sb),
+ .xinowarn = ovl_xino_warn(dir->d_sb),
};
if (rdt.xinobits && lower_layer)
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 53dd094f970e801e0f68127aafefb03661a9dd01..732ad5495c9219c5ef43939bd92ce9a4cf65f251 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -317,12 +317,6 @@ static const char *ovl_redirect_mode_def(void)
return ovl_redirect_dir_def ? "on" : "off";
}
-enum {
- OVL_XINO_OFF,
- OVL_XINO_AUTO,
- OVL_XINO_ON,
-};
-
static const char * const ovl_xino_str[] = {
"off",
"auto",
@@ -1479,8 +1473,8 @@ static int ovl_get_layers(struct super_block *sb, struct ovl_fs *ofs,
/*
* When all layers on same fs, overlay can use real inode numbers.
- * With mount option "xino=on", mounter declares that there are enough
- * free high bits in underlying fs to hold the unique fsid.
+ * With mount option "xino=<on|auto>", mounter declares that there are
+ * enough free high bits in underlying fs to hold the unique fsid.
* If overlayfs does encounter underlying inodes using the high xino
* bits reserved for fsid, it emits a warning and uses the original
* inode number or a non persistent inode number allocated from a
@@ -1492,7 +1486,7 @@ static int ovl_get_layers(struct super_block *sb, struct ovl_fs *ofs,
ofs->xino_mode = 0;
} else if (ofs->config.xino == OVL_XINO_OFF) {
ofs->xino_mode = -1;
- } else if (ofs->config.xino == OVL_XINO_ON && ofs->xino_mode < 0) {
+ } else if (ofs->xino_mode < 0) {
/*
* This is a roundup of number of bits needed for encoding
* fsid, where fsid 0 is reserved for upper fs (even with