diff options
Diffstat (limited to 'fs/overlayfs/dir.c')
-rw-r--r-- | fs/overlayfs/dir.c | 117 |
1 files changed, 52 insertions, 65 deletions
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index f9788bc116a8..a1a7606d4891 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -181,11 +181,6 @@ static bool ovl_type_origin(struct dentry *dentry) return OVL_TYPE_ORIGIN(ovl_path_type(dentry)); } -static bool ovl_may_have_whiteouts(struct dentry *dentry) -{ - return ovl_test_flag(OVL_WHITEOUTS, d_inode(dentry)); -} - static int ovl_create_upper(struct dentry *dentry, struct inode *inode, struct cattr *attr, struct dentry *hardlink) { @@ -301,37 +296,6 @@ out: return ERR_PTR(err); } -static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry) -{ - int err; - struct dentry *ret = NULL; - LIST_HEAD(list); - - err = ovl_check_empty_dir(dentry, &list); - if (err) { - ret = ERR_PTR(err); - goto out_free; - } - - /* - * When removing an empty opaque directory, then it makes no sense to - * replace it with an exact replica of itself. - * - * If upperdentry has whiteouts, clear them. - * - * Can race with copy-up, since we don't hold the upperdir mutex. - * Doesn't matter, since copy-up can't create a non-empty directory - * from an empty one. - */ - if (!list_empty(&list)) - ret = ovl_clear_empty(dentry, &list); - -out_free: - ovl_cache_free(&list); - - return ret; -} - static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name, const struct posix_acl *acl) { @@ -623,7 +587,8 @@ static bool ovl_matches_upper(struct dentry *dentry, struct dentry *upper) return d_inode(ovl_dentry_upper(dentry)) == d_inode(upper); } -static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir) +static int ovl_remove_and_whiteout(struct dentry *dentry, + struct list_head *list) { struct dentry *workdir = ovl_workdir(dentry); struct inode *wdir = workdir->d_inode; @@ -638,8 +603,8 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir) if (WARN_ON(!workdir)) return -EROFS; - if (is_dir) { - opaquedir = ovl_check_empty_and_clear(dentry); + if (!list_empty(list)) { + opaquedir = ovl_clear_empty(dentry, list); err = PTR_ERR(opaquedir); if (IS_ERR(opaquedir)) goto out; @@ -694,7 +659,8 @@ kill_whiteout: goto out_d_drop; } -static int ovl_remove_upper(struct dentry *dentry, bool is_dir) +static int ovl_remove_upper(struct dentry *dentry, bool is_dir, + struct list_head *list) { struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); struct inode *dir = upperdir->d_inode; @@ -702,10 +668,8 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir) struct dentry *opaquedir = NULL; int err; - /* Redirect/origin dir can be !ovl_lower_positive && not clean */ - if (is_dir && (ovl_dentry_get_redirect(dentry) || - ovl_may_have_whiteouts(dentry))) { - opaquedir = ovl_check_empty_and_clear(dentry); + if (!list_empty(list)) { + opaquedir = ovl_clear_empty(dentry, list); err = PTR_ERR(opaquedir); if (IS_ERR(opaquedir)) goto out; @@ -746,11 +710,26 @@ out: return err; } +static bool ovl_pure_upper(struct dentry *dentry) +{ + return !ovl_dentry_lower(dentry) && + !ovl_test_flag(OVL_WHITEOUTS, d_inode(dentry)); +} + static int ovl_do_remove(struct dentry *dentry, bool is_dir) { int err; bool locked = false; const struct cred *old_cred; + bool lower_positive = ovl_lower_positive(dentry); + LIST_HEAD(list); + + /* No need to clean pure upper removed by vfs_rmdir() */ + if (is_dir && (lower_positive || !ovl_pure_upper(dentry))) { + err = ovl_check_empty_dir(dentry, &list); + if (err) + goto out; + } err = ovl_want_write(dentry); if (err) @@ -765,10 +744,10 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir) goto out_drop_write; old_cred = ovl_override_creds(dentry->d_sb); - if (!ovl_lower_positive(dentry)) - err = ovl_remove_upper(dentry, is_dir); + if (!lower_positive) + err = ovl_remove_upper(dentry, is_dir, &list); else - err = ovl_remove_and_whiteout(dentry, is_dir); + err = ovl_remove_and_whiteout(dentry, &list); revert_creds(old_cred); if (!err) { if (is_dir) @@ -780,6 +759,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir) out_drop_write: ovl_drop_write(dentry); out: + ovl_cache_free(&list); return err; } @@ -915,6 +895,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, bool samedir = olddir == newdir; struct dentry *opaquedir = NULL; const struct cred *old_cred = NULL; + LIST_HEAD(list); err = -EINVAL; if (flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE)) @@ -929,6 +910,27 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, if (!overwrite && !ovl_can_move(new)) goto out; + if (overwrite && new_is_dir && !ovl_pure_upper(new)) { + err = ovl_check_empty_dir(new, &list); + if (err) + goto out; + } + + if (overwrite) { + if (ovl_lower_positive(old)) { + if (!ovl_dentry_is_whiteout(new)) { + /* Whiteout source */ + flags |= RENAME_WHITEOUT; + } else { + /* Switch whiteouts */ + flags |= RENAME_EXCHANGE; + } + } else if (is_dir && ovl_dentry_is_whiteout(new)) { + flags |= RENAME_EXCHANGE; + cleanup_whiteout = true; + } + } + err = ovl_want_write(old); if (err) goto out; @@ -952,9 +954,8 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, old_cred = ovl_override_creds(old->d_sb); - if (overwrite && new_is_dir && (ovl_type_merge_or_lower(new) || - ovl_may_have_whiteouts(new))) { - opaquedir = ovl_check_empty_and_clear(new); + if (!list_empty(&list)) { + opaquedir = ovl_clear_empty(new, &list); err = PTR_ERR(opaquedir); if (IS_ERR(opaquedir)) { opaquedir = NULL; @@ -962,21 +963,6 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, } } - if (overwrite) { - if (ovl_lower_positive(old)) { - if (!ovl_dentry_is_whiteout(new)) { - /* Whiteout source */ - flags |= RENAME_WHITEOUT; - } else { - /* Switch whiteouts */ - flags |= RENAME_EXCHANGE; - } - } else if (is_dir && ovl_dentry_is_whiteout(new)) { - flags |= RENAME_EXCHANGE; - cleanup_whiteout = true; - } - } - old_upperdir = ovl_dentry_upper(old->d_parent); new_upperdir = ovl_dentry_upper(new->d_parent); @@ -1094,6 +1080,7 @@ out_drop_write: ovl_drop_write(old); out: dput(opaquedir); + ovl_cache_free(&list); return err; } |