An upper dir is marked "impure" to let ovl_iterate() know that this directory may contain non pure upper entries whose d_ino may need to be read from the origin inode. We already mark a non-merge dir "impure" when moving a non-pure child entry inside it, to let ovl_iterate() know not to iterate the non-merge dir directly. Mark also a merge dir "impure" when moving a non-pure child entry inside it and when copying up a child entry inside it. This can be used to optimize ovl_iterate() to perform a "pure merge" of upper and lower directories, merging the content of the directories, without having to read d_ino from origin inodes. Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- fs/overlayfs/copy_up.c | 7 +++++++ fs/overlayfs/dir.c | 31 ++++++------------------------- fs/overlayfs/namei.c | 20 -------------------- fs/overlayfs/overlayfs.h | 14 +++++++++++--- fs/overlayfs/super.c | 5 ++++- fs/overlayfs/util.c | 31 +++++++++++++++++++++++++++++++ 6 files changed, 59 insertions(+), 49 deletions(-) Miklos, Please consider this patch for v4.12-rc3 on top of the one already in overlayfs-next. Not sure how common the use case of "pure merge" is, but the optimization of not doing the origin lookup in ovl_interate() is trivial [1], so better have the merge dir marked "impure" now when introducing overlay.origin. Amir. v3: - Fix bug that slipped into ovl_check_dir_xattr() in v1 v2: - Check on mount if upper dir is impure - Tested the optimization [1] with consistent st_ino/d_ino patch [1] https://github.com/amir73il/linux/blob/ovl-constino/fs/overlayfs/readdir.c#L413 diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 843ed2a..1ae1790 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -459,6 +459,13 @@ static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, ovl_path_upper(parent, &parentpath); upperdir = parentpath.dentry; + /* Mark parent "impure" because it may now contain non-pure upper */ + if (!ovl_dentry_is_impure(parent)) { + err = ovl_set_impure(parent, upperdir); + if (err) + return err; + } + err = vfs_getattr(&parentpath, &pstat, STATX_ATIME | STATX_MTIME, AT_STATX_SYNC_AS_STAT); if (err) diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index f2a118b..c9efc54 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -149,22 +149,6 @@ static int ovl_set_opaque(struct dentry *dentry, struct dentry *upperdentry) return ovl_set_opaque_xerr(dentry, upperdentry, -EIO); } -static int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry) -{ - int err; - - /* - * Do not fail when upper doesn't support xattrs. - * Upper inodes won't have origin nor redirect xattr anyway. - */ - err = ovl_check_setxattr(dentry, upperdentry, OVL_XATTR_IMPURE, - "y", 1, 0); - if (!err) - ovl_dentry_set_impure(dentry); - - return err; -} - /* Common operations required to be done after creation of file on upper */ static void ovl_instantiate(struct dentry *dentry, struct inode *inode, struct dentry *newdentry, bool hardlink) @@ -976,21 +960,18 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, if (!samedir) { /* * When moving a merge dir or non-dir with copy up origin into - * a non-merge upper dir (a.k.a pure upper dir), we are making - * the target parent dir "impure". ovl_iterate() iterates pure - * upper dirs directly, because there is no need to filter out - * whiteouts and merge dir content with lower dir. But for the - * case of an "impure" upper dir, ovl_iterate() cannot iterate - * the real directory directly, because it looks for the inode - * numbers to fill d_ino in the entries origin inode. + * a new parent, we are marking the new parent dir "impure". + * When ovl_iterate() iterates an "impure" upper dir, it will + * lookup the origin inodes of the entries to fill d_ino. */ - if (ovl_type_origin(old) && !ovl_type_merge(new->d_parent)) { + if (ovl_type_origin(old) && + !ovl_dentry_is_impure(new->d_parent)) { err = ovl_set_impure(new->d_parent, new_upperdir); if (err) goto out_revert_creds; } if (!overwrite && ovl_type_origin(new) && - !ovl_type_merge(old->d_parent)) { + !ovl_dentry_is_impure(old->d_parent)) { err = ovl_set_impure(old->d_parent, old_upperdir); if (err) goto out_revert_creds; diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c index 0c72a59..f3136c3 100644 --- a/fs/overlayfs/namei.c +++ b/fs/overlayfs/namei.c @@ -167,31 +167,11 @@ static struct dentry *ovl_get_origin(struct dentry *dentry, goto out; } -static bool ovl_check_dir_xattr(struct dentry *dentry, const char *name) -{ - int res; - char val; - - if (!d_is_dir(dentry)) - return false; - - res = vfs_getxattr(dentry, name, &val, 1); - if (res == 1 && val == 'y') - return true; - - return false; -} - static bool ovl_is_opaquedir(struct dentry *dentry) { return ovl_check_dir_xattr(dentry, OVL_XATTR_OPAQUE); } -static bool ovl_is_impuredir(struct dentry *dentry) -{ - return ovl_check_dir_xattr(dentry, OVL_XATTR_IMPURE); -} - static int ovl_lookup_single(struct dentry *base, struct ovl_lookup_data *d, const char *name, unsigned int namelen, size_t prelen, const char *post, diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index a9fb958..a2ca3d615 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -221,6 +221,17 @@ bool ovl_is_whiteout(struct dentry *dentry); struct file *ovl_path_open(struct path *path, int flags); int ovl_copy_up_start(struct dentry *dentry); void ovl_copy_up_end(struct dentry *dentry); +bool ovl_check_dir_xattr(struct dentry *dentry, const char *name); +int ovl_check_setxattr(struct dentry *dentry, struct dentry *upperdentry, + const char *name, const void *value, size_t size, + int xerr); +int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry); + +static inline bool ovl_is_impuredir(struct dentry *dentry) +{ + return ovl_check_dir_xattr(dentry, OVL_XATTR_IMPURE); +} + /* namei.c */ int ovl_path_next(int idx, struct dentry *dentry, struct path *path); @@ -281,6 +292,3 @@ int ovl_copy_up(struct dentry *dentry); int ovl_copy_up_flags(struct dentry *dentry, int flags); int ovl_copy_xattr(struct dentry *old, struct dentry *new); int ovl_set_attr(struct dentry *upper, struct kstat *stat); -int ovl_check_setxattr(struct dentry *dentry, struct dentry *upperdentry, - const char *name, const void *value, size_t size, - int xerr); diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index f164762..4882ffb 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -974,7 +974,10 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) path_put(&workpath); kfree(lowertmp); - oe->__upperdentry = upperpath.dentry; + if (upperpath.dentry) { + oe->__upperdentry = upperpath.dentry; + oe->impure = ovl_is_impuredir(upperpath.dentry); + } for (i = 0; i < numlower; i++) { oe->lowerstack[i].dentry = stack[i].dentry; oe->lowerstack[i].mnt = ufs->lower_mnt[i]; diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index e0dfb07..d8ce448 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -311,6 +311,21 @@ void ovl_copy_up_end(struct dentry *dentry) spin_unlock(&ofs->copyup_wq.lock); } +bool ovl_check_dir_xattr(struct dentry *dentry, const char *name) +{ + int res; + char val; + + if (!d_is_dir(dentry)) + return false; + + res = vfs_getxattr(dentry, name, &val, 1); + if (res == 1 && val == 'y') + return true; + + return false; +} + int ovl_check_setxattr(struct dentry *dentry, struct dentry *upperdentry, const char *name, const void *value, size_t size, int xerr) @@ -331,3 +346,19 @@ int ovl_check_setxattr(struct dentry *dentry, struct dentry *upperdentry, return err; } + +int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry) +{ + int err; + + /* + * Do not fail when upper doesn't support xattrs. + * Upper inodes won't have origin nor redirect xattr anyway. + */ + err = ovl_check_setxattr(dentry, upperdentry, OVL_XATTR_IMPURE, + "y", 1, 0); + if (!err) + ovl_dentry_set_impure(dentry); + + return err; +} -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
