diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 2d6251a4caaf..b0d42ece4d7c 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 e81fea86139e..e6f3670146ed 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 6325dcc4c48b..e452ff7d583d 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 53dd094f970e..732ad5495c92 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=", 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