From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Aneesh Kumar K.V" Subject: [PATCH -V19 06/15] vfs: Add handle based link syscall Date: Fri, 27 Aug 2010 16:32:53 +0530 Message-ID: <1282906982-26918-7-git-send-email-aneesh.kumar@linux.vnet.ibm.com> References: <1282906982-26918-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Cc: linux-fsdevel@vger.kernel.org, sfrench@us.ibm.com, philippe.deniel@CEA.FR, linux-kernel@vger.kernel.org, "Aneesh Kumar K.V" To: hch@infradead.org, viro@zeniv.linux.org.uk, adilger@sun.com, corbet@lwn.net, neilb@suse.de, npiggin@kernel.dk, hooanon05@yahoo.co.jp, bfields@fieldses.org, miklos@szeredi.hu Return-path: In-Reply-To: <1282906982-26918-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Signed-off-by: Aneesh Kumar K.V --- fs/namei.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/syscalls.h | 2 ++ 2 files changed, 47 insertions(+), 0 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 4718802..304b187 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2706,6 +2706,51 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0); } +SYSCALL_DEFINE4(handle_link, int, mountdirfd, struct file_handle __user *, uofh, + int, newdfd, const char __user *, newname) +{ + char *to; + int error; + struct dentry *new_dentry; + struct nameidata nd; + struct path old_path; + + error = handle_to_path(mountdirfd, uofh, &old_path); + if (error) + return error; + + error = user_path_parent(newdfd, newname, &nd, &to); + if (error) + goto out; + error = -EXDEV; + if (old_path.mnt != nd.path.mnt) + goto out_release; + new_dentry = lookup_create(&nd, 0); + error = PTR_ERR(new_dentry); + if (IS_ERR(new_dentry)) + goto out_unlock; + error = mnt_want_write(nd.path.mnt); + if (error) + goto out_dput; + error = security_path_link(old_path.dentry, &nd.path, new_dentry); + if (error) + goto out_drop_write; + error = vfs_link(old_path.dentry, nd.path.dentry->d_inode, new_dentry); +out_drop_write: + mnt_drop_write(nd.path.mnt); +out_dput: + dput(new_dentry); +out_unlock: + mutex_unlock(&nd.path.dentry->d_inode->i_mutex); +out_release: + path_put(&nd.path); + putname(to); +out: + path_put(&old_path); + + return error; +} + /* * The worst of all namespace operations - renaming directory. "Perverted" * doesn't even start to describe it. Somebody in UCB had a heck of a trip... diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index e45ef50..9c82364 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -850,4 +850,6 @@ asmlinkage long sys_handle_stat(int mountdirfd, struct file_handle __user *ufh, struct stat __user *statbuf); #endif +asmlinkage long sys_handle_link(int mountdirfd, struct file_handle __user *uofh, + int newfd, const char __user *newname); #endif -- 1.7.0.4