From: Vivek Goyal <vgoyal@redhat.com>
To: linux-unionfs@vger.kernel.org
Cc: amir73il@gmail.com, miklos@szeredi.hu, vgoyal@redhat.com
Subject: [PATCH 07/13] ovl: A new xattr OVL_XATTR_METACOPY for file on upper
Date: Wed, 25 Oct 2017 15:09:29 -0400 [thread overview]
Message-ID: <1508958575-14086-8-git-send-email-vgoyal@redhat.com> (raw)
In-Reply-To: <1508958575-14086-1-git-send-email-vgoyal@redhat.com>
Now we will have the capability to have upper inodes which might be only
metadata copy up and data is still on lower inode. So add a new xattr
OVL_XATTR_METACOPY to distinguish between two cases.
Presence of OVL_XATTR_METACOPY reflects that file has been copied up metadata
only and and data will be copied up later from lower origin.
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_UPPERDATA which reflects
whether ovl inode has data or not (as opposed to metadata only copy up).
Note, OVL_UPPERDATA is set only on those upper inodes which can possibly
be metacopy only inodes. For example, inode should be a regular file and
there needs to be a lower dentry.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
fs/overlayfs/copy_up.c | 55 +++++++++++++++++++++++++++++++++++++++++++++---
fs/overlayfs/inode.c | 3 ++-
fs/overlayfs/overlayfs.h | 6 +++++-
fs/overlayfs/util.c | 34 ++++++++++++++++++++++++++++--
4 files changed, 91 insertions(+), 7 deletions(-)
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 2936284..a6cda02 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 = {
@@ -439,6 +449,28 @@ static int ovl_get_tmpfile(struct ovl_copy_up_ctx *c, struct dentry **tempp)
goto out;
}
+/* Copy up data of an inode which was copied up metadata only in the past. */
+static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
+{
+ struct path upperpath;
+ int err;
+
+ ovl_path_upper(c->dentry, &upperpath);
+ if (WARN_ON(upperpath.dentry == NULL))
+ return -EIO;
+
+ 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;
+
+ ovl_set_flag(OVL_UPPERDATA, d_inode(c->dentry));
+ return err;
+}
+
static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp)
{
int err;
@@ -474,8 +506,19 @@ static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp)
return err;
}
+ if (c->metacopy) {
+ err = ovl_check_setxattr(c->dentry, temp, OVL_XATTR_METACOPY,
+ NULL, 0, -EOPNOTSUPP);
+ if (err)
+ return err;
+ }
+
+
inode_lock(temp->d_inode);
- err = ovl_set_attr(temp, &c->stat);
+ if (c->metacopy)
+ err = ovl_set_size(temp, &c->stat);
+ if (!err)
+ err = ovl_set_attr(temp, &c->stat);
inode_unlock(temp->d_inode);
return err;
@@ -506,6 +549,8 @@ static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c)
if (err)
goto out_cleanup;
+ if (!c->metacopy && S_ISREG(d_inode(c->dentry)->i_mode))
+ ovl_set_flag(OVL_UPPERDATA, d_inode(c->dentry));
ovl_inode_update(d_inode(c->dentry), newdentry);
out:
dput(temp);
@@ -632,7 +677,7 @@ 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)
@@ -642,6 +687,8 @@ 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_meta_inode_data(&ctx);
ovl_copy_up_end(dentry);
}
do_delayed_call(&done);
@@ -672,8 +719,10 @@ 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 321511e..1b4b42c 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 d9a0edd..714abf9 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_UPPERDATA,
};
/*
@@ -211,6 +213,8 @@ 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_dentry_check_upperdata(struct dentry *dentry);
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 +225,7 @@ 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 a4ce1c9..ef720a9 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -227,6 +227,35 @@ void ovl_dentry_set_upper_alias(struct dentry *dentry)
oe->has_upper = true;
}
+bool ovl_dentry_check_upperdata(struct dentry *dentry) {
+ if (!S_ISREG(d_inode(dentry)->i_mode))
+ return false;
+
+ if (!ovl_dentry_lower(dentry))
+ return false;
+
+ return true;
+}
+
+bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags) {
+ if (!ovl_dentry_check_upperdata(dentry))
+ return false;
+
+ if (!S_ISREG(d_inode(dentry)->i_mode))
+ return false;
+
+ if (!flags)
+ return false;
+
+ if (!(OPEN_FMODE(flags) & FMODE_WRITE))
+ return false;
+
+ if (likely(ovl_test_flag(OVL_UPPERDATA, 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 +339,14 @@ 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);
}
--
2.5.5
next prev parent reply other threads:[~2017-10-25 19:09 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-25 19:09 [RFC PATCH 00/13][V5] overlayfs: Delayed copy up of data Vivek Goyal
2017-10-25 19:09 ` [PATCH 01/13] ovl: Put upperdentry if ovl_check_origin() fails Vivek Goyal
2017-10-25 20:08 ` Amir Goldstein
2017-10-25 19:09 ` [PATCH 02/13] ovl: Create origin xattr on copy up for all files Vivek Goyal
2017-10-26 5:31 ` Amir Goldstein
2017-10-26 12:53 ` Vivek Goyal
2017-10-25 19:09 ` [PATCH 03/13] ovl: ovl_check_setxattr() get rid of redundant -EOPNOTSUPP check Vivek Goyal
2017-10-25 19:09 ` [PATCH 04/13] ovl: Provide a mount option metacopy=on/off for metadata copyup Vivek Goyal
2017-10-26 5:39 ` Amir Goldstein
2017-10-26 13:15 ` Vivek Goyal
2017-10-26 13:57 ` Amir Goldstein
2017-10-25 19:09 ` [PATCH 05/13] ovl: During copy up, first copy up metadata and then data Vivek Goyal
2017-10-26 5:42 ` Amir Goldstein
2017-10-26 13:19 ` Vivek Goyal
2017-10-25 19:09 ` [PATCH 06/13] ovl: Copy up only metadata during copy up where it makes sense Vivek Goyal
2017-10-25 19:09 ` Vivek Goyal [this message]
2017-10-26 6:04 ` [PATCH 07/13] ovl: A new xattr OVL_XATTR_METACOPY for file on upper Amir Goldstein
2017-10-26 13:53 ` Vivek Goyal
2017-10-26 14:14 ` Amir Goldstein
2017-10-26 14:34 ` Vivek Goyal
2017-10-26 16:11 ` Amir Goldstein
2017-10-27 4:28 ` Amir Goldstein
2017-10-25 19:09 ` [PATCH 08/13] ovl: Fix ovl_getattr() to get number of blocks from lower Vivek Goyal
2017-10-26 6:12 ` Amir Goldstein
2017-10-25 19:09 ` [PATCH 09/13] ovl: Set OVL_UPPERDATA flag during ovl_lookup() Vivek Goyal
2017-10-26 6:19 ` Amir Goldstein
2017-10-26 18:04 ` Vivek Goyal
2017-10-25 19:09 ` [PATCH 10/13] ovl: Return lower dentry if only metadata copy up took place Vivek Goyal
2017-10-25 19:09 ` [PATCH 11/13] ovl: Introduce read/write barriers around metacopy flag update Vivek Goyal
2017-10-26 6:34 ` Amir Goldstein
2017-10-26 17:54 ` Vivek Goyal
2017-10-27 4:35 ` Amir Goldstein
2017-10-27 13:14 ` Vivek Goyal
2017-10-25 19:09 ` [PATCH 12/13] ovl: Do not export metacopy only upper dentry Vivek Goyal
2017-10-26 6:54 ` Amir Goldstein
2017-10-26 6:54 ` Amir Goldstein
2017-10-25 19:09 ` [PATCH 13/13] ovl: Enable metadata only feature Vivek Goyal
2017-10-26 7:07 ` Amir Goldstein
2017-10-26 18:19 ` Vivek Goyal
2017-10-26 7:18 ` [RFC PATCH 00/13][V5] overlayfs: Delayed copy up of data Amir Goldstein
2017-10-27 16:40 ` Vivek Goyal
2017-10-28 14:50 ` Amir Goldstein
2017-10-31 13:39 ` Vivek Goyal
2017-10-31 13:56 ` Amir Goldstein
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1508958575-14086-8-git-send-email-vgoyal@redhat.com \
--to=vgoyal@redhat.com \
--cc=amir73il@gmail.com \
--cc=linux-unionfs@vger.kernel.org \
--cc=miklos@szeredi.hu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).