From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Goyal Subject: [PATCH 5/9] ovl: Set xattr OVL_XATTR_METACOPY on upper file Date: Tue, 10 Oct 2017 11:32:20 -0400 Message-ID: <1507649544-4539-6-git-send-email-vgoyal@redhat.com> References: <1507649544-4539-1-git-send-email-vgoyal@redhat.com> Return-path: Received: from mx1.redhat.com ([209.132.183.28]:37794 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932303AbdJJPcj (ORCPT ); Tue, 10 Oct 2017 11:32:39 -0400 In-Reply-To: <1507649544-4539-1-git-send-email-vgoyal@redhat.com> Sender: linux-unionfs-owner@vger.kernel.org List-Id: linux-unionfs@vger.kernel.org To: linux-unionfs@vger.kernel.org Cc: amir73il@gmail.com, miklos@szeredi.hu, vgoyal@redhat.com, ebiederm@xmission.com Presence of OVL_XATTR_METACOPY reflects that file has been copied up with metadata only and data needs to be copied up later from lower. So this xattr is set when a metadata copy takes place and cleared when data copy takes place. We also use a bit in ovl_inode->flags to cache OVL_METACOPY which reflects whether ovl inode has only metadata copied up. ovl_set_size() code has been taken from Amir's patch. Signed-off-by: Vivek Goyal --- fs/overlayfs/copy_up.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++-- fs/overlayfs/inode.c | 3 ++- fs/overlayfs/overlayfs.h | 5 +++- fs/overlayfs/util.c | 21 ++++++++++++++-- 4 files changed, 88 insertions(+), 6 deletions(-) diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index ebd404629c6d..682852a78163 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -196,6 +196,16 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len) return error; } +static int ovl_set_size(struct dentry *upperdentry, struct kstat *stat) +{ + struct iattr attr = { + .ia_valid = ATTR_SIZE, + .ia_size = stat->size, + }; + + return notify_change(upperdentry, &attr, NULL); +} + static int ovl_set_timestamps(struct dentry *upperdentry, struct kstat *stat) { struct iattr attr = { @@ -439,9 +449,31 @@ static int ovl_get_tmpfile(struct ovl_copy_up_ctx *c, struct dentry **tempp) goto out; } +static int ovl_copy_up_data_inode(struct ovl_copy_up_ctx *c) +{ + struct path upperpath; + int err; + + ovl_path_upper(c->dentry, &upperpath); + BUG_ON(upperpath.dentry == NULL); + + err = ovl_copy_up_data(&c->lowerpath, &upperpath, c->stat.size); + if (err) + return err; + + err= vfs_removexattr(upperpath.dentry, OVL_XATTR_METACOPY); + if (err) + return err; + + smp_wmb(); + ovl_clear_flag(OVL_METACOPY, d_inode(c->dentry)); + return err; +} + static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp) { int err; + bool set_size = false; err = ovl_copy_xattr(c->lowerpath.dentry, temp); if (err) @@ -476,8 +508,29 @@ static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp) return err; } + if (c->metadata_only) { + err = ovl_check_setxattr(c->dentry, temp, OVL_XATTR_METACOPY, + NULL, 0, -EOPNOTSUPP); + if (err) + return err; + + set_size = true; + } + inode_lock(temp->d_inode); + if (set_size) { + err = ovl_set_size(temp, &c->stat); + if (err) { + inode_unlock(temp->d_inode); + return err; + } + } + err = ovl_set_attr(temp, &c->stat); + if (err) { + inode_unlock(temp->d_inode); + return err; + } inode_unlock(temp->d_inode); if (err) return err; @@ -511,6 +564,10 @@ static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c) goto out_cleanup; ovl_inode_update(d_inode(c->dentry), newdentry); + if (c->metadata_only) { + smp_wmb(); + ovl_set_flag(OVL_METACOPY, d_inode(c->dentry)); + } out: dput(temp); return err; @@ -639,7 +696,7 @@ static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, } ovl_do_check_copy_up(ctx.lowerpath.dentry); - err = ovl_copy_up_start(dentry); + err = ovl_copy_up_start(dentry, flags); /* err < 0: interrupted, err > 0: raced with another copy-up */ if (unlikely(err)) { if (err > 0) @@ -649,6 +706,8 @@ static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, err = ovl_do_copy_up(&ctx); if (!err && !ovl_dentry_has_upper_alias(dentry)) err = ovl_link_up(&ctx); + if (!err && ovl_dentry_needs_data_copy_up(dentry, flags)) + err = ovl_copy_up_data_inode(&ctx); ovl_copy_up_end(dentry); } do_delayed_call(&done); @@ -679,8 +738,10 @@ int ovl_copy_up_flags(struct dentry *dentry, int flags) * with rename. */ if (ovl_dentry_upper(dentry) && - ovl_dentry_has_upper_alias(dentry)) + ovl_dentry_has_upper_alias(dentry) && + !ovl_dentry_needs_data_copy_up(dentry, flags)) { break; + } next = dget(dentry); /* find the topmost dentry not yet copied up */ diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index a619addecafc..e5825b8948e0 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -320,7 +320,8 @@ struct posix_acl *ovl_get_acl(struct inode *inode, int type) static bool ovl_open_need_copy_up(struct dentry *dentry, int flags) { if (ovl_dentry_upper(dentry) && - ovl_dentry_has_upper_alias(dentry)) + ovl_dentry_has_upper_alias(dentry) && + !ovl_dentry_needs_data_copy_up(dentry, flags)) return false; if (special_file(d_inode(dentry)->i_mode)) diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index c706a6f99928..773f5ad75729 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -26,10 +26,12 @@ enum ovl_path_type { #define OVL_XATTR_ORIGIN OVL_XATTR_PREFIX "origin" #define OVL_XATTR_IMPURE OVL_XATTR_PREFIX "impure" #define OVL_XATTR_NLINK OVL_XATTR_PREFIX "nlink" +#define OVL_XATTR_METACOPY OVL_XATTR_PREFIX "metacopy" enum ovl_flag { OVL_IMPURE, OVL_INDEX, + OVL_METACOPY, }; /* @@ -211,6 +213,7 @@ bool ovl_dentry_is_whiteout(struct dentry *dentry); void ovl_dentry_set_opaque(struct dentry *dentry); bool ovl_dentry_has_upper_alias(struct dentry *dentry); void ovl_dentry_set_upper_alias(struct dentry *dentry); +bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags); bool ovl_redirect_dir(struct super_block *sb); const char *ovl_dentry_get_redirect(struct dentry *dentry); void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect); @@ -221,7 +224,7 @@ void ovl_dentry_version_inc(struct dentry *dentry, bool impurity); u64 ovl_dentry_version_get(struct dentry *dentry); 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); +int ovl_copy_up_start(struct dentry *dentry, int flags); 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, diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index a4ce1c9944f0..91c542d1a39d 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -227,6 +227,22 @@ void ovl_dentry_set_upper_alias(struct dentry *dentry) oe->has_upper = true; } +bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags) { + if (!S_ISREG(d_inode(dentry)->i_mode)) + return false; + + if (!flags) + return false; + + if (!(OPEN_FMODE(flags) & FMODE_WRITE)) + return false; + + if (!ovl_test_flag(OVL_METACOPY, d_inode(dentry))) + return false; + + return true; +} + bool ovl_redirect_dir(struct super_block *sb) { struct ovl_fs *ofs = sb->s_fs_info; @@ -310,13 +326,14 @@ struct file *ovl_path_open(struct path *path, int flags) return dentry_open(path, flags | O_NOATIME, current_cred()); } -int ovl_copy_up_start(struct dentry *dentry) +int ovl_copy_up_start(struct dentry *dentry, int flags) { struct ovl_inode *oi = OVL_I(d_inode(dentry)); int err; err = mutex_lock_interruptible(&oi->lock); - if (!err && ovl_dentry_has_upper_alias(dentry)) { + if (!err && ovl_dentry_has_upper_alias(dentry) && + !ovl_dentry_needs_data_copy_up(dentry, flags)) { err = 1; /* Already copied up */ mutex_unlock(&oi->lock); } -- 2.13.5