From: Amir Goldstein <amir73il@gmail.com>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: linux-unionfs@vger.kernel.org
Subject: [PATCH 3/6] ovl: check if all layers are on the same fs
Date: Wed, 29 Mar 2017 17:36:03 +0300 [thread overview]
Message-ID: <1490798166-22310-4-git-send-email-amir73il@gmail.com> (raw)
In-Reply-To: <1490798166-22310-1-git-send-email-amir73il@gmail.com>
Some features can only work when all layers are on the same fs.
Check that during mount time, so features can test it later.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
fs/overlayfs/ovl_entry.h | 3 ++-
fs/overlayfs/super.c | 7 +++++++
2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index 12c4922..0e159c3 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -27,7 +27,8 @@ struct ovl_fs {
struct ovl_config config;
/* creds of process who forced instantiation of super block */
const struct cred *creator_cred;
- bool tmpfile;
+ bool tmpfile; /* upper supports O_TMPFILE */
+ bool samefs; /* all layers on same fs */
wait_queue_head_t copyup_wq;
};
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 6d9766f..b8a83e8 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -876,6 +876,8 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
ufs->lower_mnt = kcalloc(numlower, sizeof(struct vfsmount *), GFP_KERNEL);
if (ufs->lower_mnt == NULL)
goto out_put_workdir;
+
+ ufs->samefs = true;
for (i = 0; i < numlower; i++) {
struct vfsmount *mnt = clone_private_mount(&stack[i]);
@@ -892,6 +894,11 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
ufs->lower_mnt[ufs->numlower] = mnt;
ufs->numlower++;
+
+ /* Check if all layers on same sb */
+ if ((ufs->upper_mnt && ufs->upper_mnt->mnt_sb != mnt->mnt_sb) ||
+ (i > 0 && ufs->lower_mnt[0]->mnt_sb != mnt->mnt_sb))
+ ufs->samefs = false;
}
/* If the upper fs is nonexistent, we mark overlayfs r/o too */
--
2.7.4
next prev parent reply other threads:[~2017-03-29 14:36 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-29 14:36 [PATCH 0/6] ovl: consistent_fd feature Amir Goldstein
2017-03-29 14:36 ` [PATCH 1/6] ovl: store path type in dentry Amir Goldstein
2017-03-29 14:36 ` [PATCH 2/6] ovl: cram opaque boolean into type flags Amir Goldstein
2017-03-29 14:36 ` Amir Goldstein [this message]
2017-03-29 14:36 ` [PATCH 4/6] ovl: check if clone from lower to upper is supported Amir Goldstein
2017-03-29 14:36 ` [PATCH 5/6] ovl: copy on read with consistent_fd feature Amir Goldstein
2017-03-30 11:28 ` Amir Goldstein
2017-03-31 17:58 ` Vivek Goyal
2017-04-01 9:27 ` Amir Goldstein
2017-04-05 13:20 ` Amir Goldstein
2017-03-29 14:36 ` [PATCH 6/6] ovl: link upper tempfile on open for write Amir Goldstein
2017-03-30 11:26 ` [PATCH 7/7] ovl: prevent copy on read if no upper/work dir Amir Goldstein
2017-03-30 11:34 ` [PATCH 0/6] ovl: consistent_fd feature Amir Goldstein
2017-04-06 15:20 ` Miklos Szeredi
2017-04-06 15:37 ` Miklos Szeredi
2017-04-06 16:25 ` Amir Goldstein
2017-04-07 9:32 ` Miklos Szeredi
2017-04-07 9:56 ` Miklos Szeredi
2017-04-07 10:47 ` Amir Goldstein
2017-04-07 13:03 ` Miklos Szeredi
2017-04-07 15:07 ` Amir Goldstein
2017-04-06 16:46 ` Amir Goldstein
2017-04-07 9:43 ` Miklos Szeredi
2017-04-07 11:04 ` Amir Goldstein
2017-04-08 3:03 ` J. R. Okajima
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=1490798166-22310-4-git-send-email-amir73il@gmail.com \
--to=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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.