linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Amir Goldstein <amir73il@gmail.com>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>,
	linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: [PATCH v4 2/6] ovl: check if upperdir fs supports O_TMPFILE
Date: Tue, 17 Jan 2017 06:34:53 +0200	[thread overview]
Message-ID: <1484627697-17262-3-git-send-email-amir73il@gmail.com> (raw)
In-Reply-To: <1484627697-17262-1-git-send-email-amir73il@gmail.com>

This is needed for choosing between concurrent copyup
using O_TMPFILE and legacy copyup using workdir+rename.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
 fs/overlayfs/overlayfs.h |  9 +++++++++
 fs/overlayfs/ovl_entry.h |  1 +
 fs/overlayfs/super.c     | 10 ++++++++++
 3 files changed, 20 insertions(+)

diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 8af450b..3822a90 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -127,6 +127,15 @@ static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry)
 	return err;
 }
 
+static inline struct dentry *ovl_do_tmpfile(struct dentry *dentry, umode_t mode)
+{
+	struct dentry *ret = vfs_tmpfile(dentry, mode, 0);
+	int err = IS_ERR(ret) ? PTR_ERR(ret) : 0;
+
+	pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err);
+	return ret;
+}
+
 static inline struct inode *ovl_inode_real(struct inode *inode, bool *is_upper)
 {
 	unsigned long x = (unsigned long) READ_ONCE(inode->i_private);
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index d14bca1..65f24000 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -27,6 +27,7 @@ struct ovl_fs {
 	struct ovl_config config;
 	/* creds of process who forced instantiation of super block */
 	const struct cred *creator_cred;
+	bool tmpfile;
 };
 
 /* private information held for every overlayfs dentry */
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 20f48ab..ff05065 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -825,6 +825,8 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
 		 * creation of workdir in previous step.
 		 */
 		if (ufs->workdir) {
+			struct dentry *temp;
+
 			err = ovl_check_d_type_supported(&workpath);
 			if (err < 0)
 				goto out_put_workdir;
@@ -836,6 +838,14 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
 			 */
 			if (!err)
 				pr_warn("overlayfs: upper fs needs to support d_type.\n");
+
+			/* Check if upper/work fs supports O_TMPFILE */
+			temp = ovl_do_tmpfile(ufs->workdir, S_IFREG | 0);
+			ufs->tmpfile = !IS_ERR(temp);
+			if (ufs->tmpfile)
+				dput(temp);
+			else
+				pr_warn("overlayfs: upper fs does not support tmpfile.\n");
 		}
 	}
 
-- 
2.7.4


  parent reply	other threads:[~2017-01-17  4:36 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-01-17  4:34 [PATCH v4 0/6] ovl: concurrent copy up Amir Goldstein
2017-01-17  4:34 ` [PATCH v4 1/6] vfs: create vfs helper vfs_tmpfile() Amir Goldstein
2017-03-06 14:59   ` J. R. Okajima
2017-03-06 15:29     ` Amir Goldstein
2017-01-17  4:34 ` Amir Goldstein [this message]
2017-01-17  4:34 ` [PATCH v4 3/6] ovl: rearrange code in ovl_copy_up_locked() Amir Goldstein
2017-01-17  4:34 ` [PATCH v4 4/6] ovl: copy up regular file using O_TMPFILE Amir Goldstein
2017-01-17  4:34 ` [PATCH v4 5/6] ovl: introduce copy up waitqueue Amir Goldstein
2017-01-17  4:34 ` [PATCH v4 6/6] ovl: concurrent copy up of regular files Amir Goldstein
2017-01-30 16:18 ` [PATCH v4 0/6] ovl: concurrent copy up Miklos Szeredi

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=1484627697-17262-3-git-send-email-amir73il@gmail.com \
    --to=amir73il@gmail.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-unionfs@vger.kernel.org \
    --cc=miklos@szeredi.hu \
    --cc=viro@zeniv.linux.org.uk \
    /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).