From: Valerie Aurora <valerie.aurora@gmail.com>
To: linux-fsdevel@vger.kernel.org, linux@vger.kernel.org
Cc: viro@zeniv.linux.org.uk, Valerie Aurora <vaurora@redhat.com>,
Valerie Aurora <valerie.aurora@gmail.com>
Subject: [PATCH 67/74] union-mount: Implement union-aware writable open()
Date: Tue, 22 Mar 2011 19:04:58 -0700 [thread overview]
Message-ID: <1300845905-14433-24-git-send-email-valerie.aurora@gmail.com> (raw)
In-Reply-To: <1300845905-14433-1-git-send-email-valerie.aurora@gmail.com>
From: Valerie Aurora <vaurora@redhat.com>
Copy up a file when opened with write permissions. Does not copy up
the file data when O_TRUNC is specified.
Signed-off-by: Valerie Aurora <valerie.aurora@gmail.com>
---
fs/namei.c | 28 ++++++++++++++++++++++++++++
1 files changed, 28 insertions(+), 0 deletions(-)
diff --git a/fs/namei.c b/fs/namei.c
index 6c7cff3..7e17d13 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1945,6 +1945,24 @@ exit:
return ERR_PTR(error);
}
+static int open_union_copyup(struct nameidata *nd, struct path *path,
+ int open_flag)
+{
+ struct vfsmount *oldmnt = path->mnt;
+ int error;
+
+ if (open_flag & O_TRUNC)
+ error = union_copyup_len(nd, path, 0);
+ else
+ error = union_copyup(nd, path);
+ if (error)
+ return error;
+ if (oldmnt != path->mnt)
+ mntput(nd->path.mnt);
+
+ return error;
+}
+
static struct file *do_last(struct nameidata *nd, struct path *path,
int open_flag, int acc_mode,
int mode, const char *pathname)
@@ -1996,6 +2014,11 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
if (!path->dentry->d_inode->i_op->lookup)
goto exit_dput;
}
+ if (acc_mode & MAY_WRITE) {
+ error = open_union_copyup(nd, path, open_flag);
+ if (error)
+ goto exit_dput;
+ }
path_to_nameidata(path, nd);
audit_inode(pathname, nd->path.dentry);
goto ok;
@@ -2067,6 +2090,11 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
if (path->dentry->d_inode->i_op->follow_link)
return NULL;
+ if (acc_mode & MAY_WRITE) {
+ error = open_union_copyup(nd, path, open_flag);
+ if (error)
+ goto exit_dput;
+ }
path_to_nameidata(path, nd);
error = -EISDIR;
if (S_ISDIR(path->dentry->d_inode->i_mode))
--
1.7.0.4
next prev parent reply other threads:[~2011-03-23 2:06 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-23 2:04 [PATCH 44/74] union-mount: Temporarily disable some syscalls Valerie Aurora
2011-03-23 2:04 ` [PATCH 45/74] union-mount: Basic infrastructure of __lookup_union() Valerie Aurora
2011-03-23 2:04 ` [PATCH 46/74] union-mount: Process negative dentries in __lookup_union() Valerie Aurora
2011-03-23 2:04 ` [PATCH 47/74] union-mount: Return files found in lower layers " Valerie Aurora
2011-03-23 2:04 ` [PATCH 48/74] union-mount: Build union stack " Valerie Aurora
2011-03-23 2:04 ` [PATCH 49/74] union-mount: Follow mount " Valerie Aurora
2011-03-23 2:04 ` [PATCH 50/74] union-mount: Add lookup_union() Valerie Aurora
2011-03-23 2:04 ` [PATCH 51/74] union-mount: Add do_lookup_union() wrapper for __lookup_union() Valerie Aurora
2011-03-23 2:04 ` [PATCH 52/74] union-mount: Call union lookup functions in lookup path Valerie Aurora
2011-03-23 2:04 ` [PATCH 53/74] union-mount: Create whiteout on unlink() Valerie Aurora
2011-03-23 2:04 ` [PATCH 54/74] union-mount: Create whiteout on rmdir() Valerie Aurora
2011-03-23 2:04 ` [PATCH 55/74] union-mount: Set opaque flag on new directories in unioned file systems Valerie Aurora
2011-03-23 2:04 ` [PATCH 56/74] union-mount: Copy up directory entries on first readdir() Valerie Aurora
2011-03-23 2:04 ` [PATCH 57/74] union-mount: Add generic_readdir_fallthru() helper Valerie Aurora
2011-03-23 2:04 ` [PATCH 58/74] fallthru: ext2 support for lookup of d_type/d_ino in fallthrus Valerie Aurora
2011-03-23 2:04 ` [PATCH 59/74] fallthru: tmpfs " Valerie Aurora
2011-03-23 2:04 ` [PATCH 60/74] fallthru: jffs2 " Valerie Aurora
2011-03-23 2:04 ` [PATCH 61/74] VFS: Split inode_permission() and create path_permission() Valerie Aurora
2011-03-23 2:04 ` [PATCH 62/74] VFS: Create user_path_nd() to lookup both parent and target Valerie Aurora
2011-03-23 2:04 ` [PATCH 63/74] union-mount: In-kernel file copyup routines Valerie Aurora
2011-03-23 2:04 ` [PATCH 64/74] union-mount: Implement union-aware access()/faccessat() Valerie Aurora
2011-03-23 2:04 ` [PATCH 65/74] union-mount: Implement union-aware link() Valerie Aurora
2011-03-23 2:04 ` [PATCH 66/74] union-mount: Implement union-aware rename() Valerie Aurora
2011-03-23 2:04 ` Valerie Aurora [this message]
2011-03-23 2:04 ` [PATCH 68/74] union-mount: Implement union-aware chown() Valerie Aurora
2011-03-23 2:05 ` [PATCH 69/74] union-mount: Implement union-aware truncate() Valerie Aurora
2011-03-23 2:05 ` [PATCH 70/74] union-mount: Implement union-aware chmod()/fchmodat() Valerie Aurora
2011-03-23 2:05 ` [PATCH 71/74] union-mount: Implement union-aware lchown() Valerie Aurora
2011-03-23 2:05 ` [PATCH 72/74] union-mount: Implement union-aware utimensat() Valerie Aurora
2011-03-23 2:05 ` [PATCH 73/74] union-mount: Implement union-aware setxattr() Valerie Aurora
2011-03-23 2:05 ` [PATCH 74/74] union-mount: Implement union-aware lsetxattr() Valerie Aurora
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