From d8514d8edb5b045cf7f708e14f888ce760d60f0b Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Tue, 17 Jan 2017 06:34:55 +0200 Subject: ovl: copy up regular file using O_TMPFILE In preparation for concurrent copy up, implement copy up of regular file as O_TMPFILE that is linked to upperdir instead of a file in workdir that is moved to upperdir. Suggested-by: Al Viro Signed-off-by: Amir Goldstein Signed-off-by: Miklos Szeredi --- fs/overlayfs/copy_up.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) (limited to 'fs/overlayfs') diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 01e332725e94..6e39e90b5605 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -20,6 +20,7 @@ #include #include #include "overlayfs.h" +#include "ovl_entry.h" #define OVL_COPY_UP_CHUNK_SIZE (1 << 20) @@ -233,7 +234,7 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat) static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir, struct dentry *dentry, struct path *lowerpath, struct kstat *stat, const char *link, - struct kstat *pstat) + struct kstat *pstat, bool tmpfile) { struct inode *wdir = workdir->d_inode; struct inode *udir = upperdir->d_inode; @@ -263,12 +264,17 @@ static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir, if (new_creds) old_creds = override_creds(new_creds); - temp = ovl_lookup_temp(workdir, dentry); + if (tmpfile) + temp = ovl_do_tmpfile(upperdir, stat->mode); + else + temp = ovl_lookup_temp(workdir, dentry); err = PTR_ERR(temp); if (IS_ERR(temp)) goto out1; - err = ovl_create_real(wdir, temp, &cattr, NULL, true); + err = 0; + if (!tmpfile) + err = ovl_create_real(wdir, temp, &cattr, NULL, true); if (new_creds) { revert_creds(old_creds); @@ -300,11 +306,14 @@ static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir, if (err) goto out_cleanup; - err = ovl_do_rename(wdir, temp, udir, upper, 0); + if (tmpfile) + err = ovl_do_link(temp, udir, upper, true); + else + err = ovl_do_rename(wdir, temp, udir, upper, 0); if (err) goto out_cleanup; - newdentry = dget(temp); + newdentry = dget(tmpfile ? upper : temp); ovl_dentry_update(dentry, newdentry); ovl_inode_update(d_inode(dentry), d_inode(newdentry)); @@ -318,7 +327,8 @@ out: return err; out_cleanup: - ovl_cleanup(wdir, temp); + if (!tmpfile) + ovl_cleanup(wdir, temp); goto out2; } @@ -342,6 +352,9 @@ static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, struct dentry *lowerdentry = lowerpath->dentry; struct dentry *upperdir; const char *link = NULL; + struct ovl_fs *ofs = dentry->d_sb->s_fs_info; + /* Should we copyup with O_TMPFILE or with workdir? */ + bool tmpfile = S_ISREG(stat->mode) && ofs->tmpfile; if (WARN_ON(!workdir)) return -EROFS; @@ -373,7 +386,7 @@ static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, } err = ovl_copy_up_locked(workdir, upperdir, dentry, lowerpath, - stat, link, &pstat); + stat, link, &pstat, tmpfile); out_unlock: unlock_rename(workdir, upperdir); do_delayed_call(&done); -- cgit v1.2.3-59-g8ed1b