| Message ID | 1372882356-14168-9-git-send-email-bfields@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 3 Jul 2013 16:12:32 -0400 "J. Bruce Fields" <bfields@redhat.com> wrote: > From: "J. Bruce Fields" <bfields@redhat.com> > > We need to break delegations on any operation that changes the set of > links pointing to an inode. Start with unlink. > > Such operations also hold the i_mutex on a parent directory. Breaking a > delegation may require waiting for a timeout (by default 90 seconds) in > the case of a unresponsive NFS client. To avoid blocking all directory > operations, we therefore drop locks before waiting for the delegation. > The logic then looks like: > > acquire locks > ... > test for delegation; if found: > take reference on inode > release locks > wait for delegation break > drop reference on inode > retry > > It is possible this could never terminate. (Even if we take precautions > to prevent another delegation being acquired on the same inode, we could > get a different inode on each retry.) But this seems very unlikely. > > The initial test for a delegation happens after the lock on the target > inode is acquired, but the directory inode may have been acquired > further up the call stack. We therefore add a "struct inode **" > argument to any intervening functions, which we use to pass the inode > back up to the caller in the case it needs a delegation synchronously > broken. > > Cc: David Howells <dhowells@redhat.com> > Cc: Tyler Hicks <tyhicks@canonical.com> > Cc: Dustin Kirkland <dustin.kirkland@gazzang.com> > Signed-off-by: J. Bruce Fields <bfields@redhat.com> > --- > drivers/base/devtmpfs.c | 2 +- > fs/cachefiles/namei.c | 2 +- > fs/ecryptfs/inode.c | 2 +- > fs/namei.c | 24 +++++++++++++++++++++--- > fs/nfsd/vfs.c | 2 +- > include/linux/fs.h | 2 +- > ipc/mqueue.c | 2 +- > 7 files changed, 27 insertions(+), 9 deletions(-) > > diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c > index 7413d06..1b8490e 100644 > --- a/drivers/base/devtmpfs.c > +++ b/drivers/base/devtmpfs.c > @@ -324,7 +324,7 @@ static int handle_remove(const char *nodename, struct device *dev) > mutex_lock(&dentry->d_inode->i_mutex); > notify_change(dentry, &newattrs); > mutex_unlock(&dentry->d_inode->i_mutex); > - err = vfs_unlink(parent.dentry->d_inode, dentry); > + err = vfs_unlink(parent.dentry->d_inode, dentry, NULL); > if (!err || err == -ENOENT) > deleted = 1; > } > diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c > index 8c01c5fc..d61d884 100644 > --- a/fs/cachefiles/namei.c > +++ b/fs/cachefiles/namei.c > @@ -294,7 +294,7 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache, > if (ret < 0) { > cachefiles_io_error(cache, "Unlink security error"); > } else { > - ret = vfs_unlink(dir->d_inode, rep); > + ret = vfs_unlink(dir->d_inode, rep, NULL); > > if (preemptive) > cachefiles_mark_object_buried(cache, rep); > diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c > index 5eab400..af42d88 100644 > --- a/fs/ecryptfs/inode.c > +++ b/fs/ecryptfs/inode.c > @@ -153,7 +153,7 @@ static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry, > > dget(lower_dentry); > lower_dir_dentry = lock_parent(lower_dentry); > - rc = vfs_unlink(lower_dir_inode, lower_dentry); > + rc = vfs_unlink(lower_dir_inode, lower_dentry, NULL); > if (rc) { > printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); > goto out_unlock; > diff --git a/fs/namei.c b/fs/namei.c > index 7e76fe1..cba3db1 100644 > --- a/fs/namei.c > +++ b/fs/namei.c > @@ -3384,7 +3384,7 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname) > return do_rmdir(AT_FDCWD, pathname); > } > > -int vfs_unlink(struct inode *dir, struct dentry *dentry) > +int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode) nit: this might be a good time to add a kerneldoc header on this function. The delegated_inode thing might not be clear to the uninitiated. > { > struct inode *target = dentry->d_inode; > int error = may_delete(dir, dentry, 0); > @@ -3401,11 +3401,20 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry) > else { > error = security_inode_unlink(dir, dentry); > if (!error) { > + error = break_deleg(target, O_WRONLY|O_NONBLOCK); > + if (error) { > + if (error == -EWOULDBLOCK && delegated_inode) { > + *delegated_inode = target; > + ihold(target); > + } > + goto out; > + } > error = dir->i_op->unlink(dir, dentry); > if (!error) > dont_mount(dentry); > } > } > +out: > mutex_unlock(&target->i_mutex); > > /* We don't d_delete() NFS sillyrenamed files--they still exist. */ > @@ -3430,6 +3439,7 @@ static long do_unlinkat(int dfd, const char __user *pathname) > struct dentry *dentry; > struct nameidata nd; > struct inode *inode = NULL; > + struct inode *delegated_inode = NULL; > unsigned int lookup_flags = 0; > retry: > name = user_path_parent(dfd, pathname, &nd, lookup_flags); > @@ -3444,7 +3454,7 @@ retry: > error = mnt_want_write(nd.path.mnt); > if (error) > goto exit1; > - > +retry_deleg: > mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); > dentry = lookup_hash(&nd); > error = PTR_ERR(dentry); > @@ -3459,13 +3469,21 @@ retry: > error = security_path_unlink(&nd.path, dentry); > if (error) > goto exit2; > - error = vfs_unlink(nd.path.dentry->d_inode, dentry); > + error = vfs_unlink(nd.path.dentry->d_inode, dentry, &delegated_inode); > exit2: > dput(dentry); > } > mutex_unlock(&nd.path.dentry->d_inode->i_mutex); > if (inode) > iput(inode); /* truncate the inode here */ > + inode = NULL; > + if (delegated_inode) { > + error = break_deleg(delegated_inode, O_WRONLY); > + iput(delegated_inode); > + delegated_inode = NULL; > + if (!error) > + goto retry_deleg; > + } > mnt_drop_write(nd.path.mnt); > exit1: > path_put(&nd.path); > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c > index 84ce601..6ccaca2 100644 > --- a/fs/nfsd/vfs.c > +++ b/fs/nfsd/vfs.c > @@ -1882,7 +1882,7 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, > if (host_err) > goto out_put; > if (type != S_IFDIR) > - host_err = vfs_unlink(dirp, rdentry); > + host_err = vfs_unlink(dirp, rdentry, NULL); > else > host_err = vfs_rmdir(dirp, rdentry); > if (!host_err) > diff --git a/include/linux/fs.h b/include/linux/fs.h > index c6cc686..f951588 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -1463,7 +1463,7 @@ extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t); > extern int vfs_symlink(struct inode *, struct dentry *, const char *); > extern int vfs_link(struct dentry *, struct inode *, struct dentry *); > extern int vfs_rmdir(struct inode *, struct dentry *); > -extern int vfs_unlink(struct inode *, struct dentry *); > +extern int vfs_unlink(struct inode *, struct dentry *, struct inode **); > extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); > > /* > diff --git a/ipc/mqueue.c b/ipc/mqueue.c > index e4e47f6..384eb35 100644 > --- a/ipc/mqueue.c > +++ b/ipc/mqueue.c > @@ -884,7 +884,7 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name) > err = -ENOENT; > } else { > ihold(inode); > - err = vfs_unlink(dentry->d_parent->d_inode, dentry); > + err = vfs_unlink(dentry->d_parent->d_inode, dentry, NULL); > } > dput(dentry); > We probably also ought to eyeball some of these other cases where you passing in NULL as the deleg_inode too. It's probably reasonable in most cases -- exporting a filesystem that you also mount using ecryptfs seems silly, but you never know... Looks reasonable otherwise, if a little convoluted.
On Tue, 9 Jul 2013 09:05:06 -0400 Jeff Layton <jlayton@redhat.com> wrote: > On Wed, 3 Jul 2013 16:12:32 -0400 > "J. Bruce Fields" <bfields@redhat.com> wrote: > > > From: "J. Bruce Fields" <bfields@redhat.com> > > > > We need to break delegations on any operation that changes the set of > > links pointing to an inode. Start with unlink. > > > > Such operations also hold the i_mutex on a parent directory. Breaking a > > delegation may require waiting for a timeout (by default 90 seconds) in > > the case of a unresponsive NFS client. To avoid blocking all directory > > operations, we therefore drop locks before waiting for the delegation. > > The logic then looks like: > > > > acquire locks > > ... > > test for delegation; if found: > > take reference on inode > > release locks > > wait for delegation break > > drop reference on inode > > retry > > > > It is possible this could never terminate. (Even if we take precautions > > to prevent another delegation being acquired on the same inode, we could > > get a different inode on each retry.) But this seems very unlikely. > > > > The initial test for a delegation happens after the lock on the target > > inode is acquired, but the directory inode may have been acquired > > further up the call stack. We therefore add a "struct inode **" > > argument to any intervening functions, which we use to pass the inode > > back up to the caller in the case it needs a delegation synchronously > > broken. > > > > Cc: David Howells <dhowells@redhat.com> > > Cc: Tyler Hicks <tyhicks@canonical.com> > > Cc: Dustin Kirkland <dustin.kirkland@gazzang.com> > > Signed-off-by: J. Bruce Fields <bfields@redhat.com> > > --- > > drivers/base/devtmpfs.c | 2 +- > > fs/cachefiles/namei.c | 2 +- > > fs/ecryptfs/inode.c | 2 +- > > fs/namei.c | 24 +++++++++++++++++++++--- > > fs/nfsd/vfs.c | 2 +- > > include/linux/fs.h | 2 +- > > ipc/mqueue.c | 2 +- > > 7 files changed, 27 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c > > index 7413d06..1b8490e 100644 > > --- a/drivers/base/devtmpfs.c > > +++ b/drivers/base/devtmpfs.c > > @@ -324,7 +324,7 @@ static int handle_remove(const char *nodename, struct device *dev) > > mutex_lock(&dentry->d_inode->i_mutex); > > notify_change(dentry, &newattrs); > > mutex_unlock(&dentry->d_inode->i_mutex); > > - err = vfs_unlink(parent.dentry->d_inode, dentry); > > + err = vfs_unlink(parent.dentry->d_inode, dentry, NULL); > > if (!err || err == -ENOENT) > > deleted = 1; > > } > > diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c > > index 8c01c5fc..d61d884 100644 > > --- a/fs/cachefiles/namei.c > > +++ b/fs/cachefiles/namei.c > > @@ -294,7 +294,7 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache, > > if (ret < 0) { > > cachefiles_io_error(cache, "Unlink security error"); > > } else { > > - ret = vfs_unlink(dir->d_inode, rep); > > + ret = vfs_unlink(dir->d_inode, rep, NULL); > > > > if (preemptive) > > cachefiles_mark_object_buried(cache, rep); > > diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c > > index 5eab400..af42d88 100644 > > --- a/fs/ecryptfs/inode.c > > +++ b/fs/ecryptfs/inode.c > > @@ -153,7 +153,7 @@ static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry, > > > > dget(lower_dentry); > > lower_dir_dentry = lock_parent(lower_dentry); > > - rc = vfs_unlink(lower_dir_inode, lower_dentry); > > + rc = vfs_unlink(lower_dir_inode, lower_dentry, NULL); > > if (rc) { > > printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); > > goto out_unlock; > > diff --git a/fs/namei.c b/fs/namei.c > > index 7e76fe1..cba3db1 100644 > > --- a/fs/namei.c > > +++ b/fs/namei.c > > @@ -3384,7 +3384,7 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname) > > return do_rmdir(AT_FDCWD, pathname); > > } > > > > -int vfs_unlink(struct inode *dir, struct dentry *dentry) > > +int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode) > > nit: this might be a good time to add a kerneldoc header on this > function. The delegated_inode thing might not be clear to the > uninitiated. > > > { > > struct inode *target = dentry->d_inode; > > int error = may_delete(dir, dentry, 0); > > @@ -3401,11 +3401,20 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry) > > else { > > error = security_inode_unlink(dir, dentry); > > if (!error) { > > + error = break_deleg(target, O_WRONLY|O_NONBLOCK); > > + if (error) { > > + if (error == -EWOULDBLOCK && delegated_inode) { > > + *delegated_inode = target; > > + ihold(target); > > + } > > + goto out; > > + } > > error = dir->i_op->unlink(dir, dentry); > > if (!error) > > dont_mount(dentry); > > } > > } > > +out: > > mutex_unlock(&target->i_mutex); > > > > /* We don't d_delete() NFS sillyrenamed files--they still exist. */ > > @@ -3430,6 +3439,7 @@ static long do_unlinkat(int dfd, const char __user *pathname) > > struct dentry *dentry; > > struct nameidata nd; > > struct inode *inode = NULL; > > + struct inode *delegated_inode = NULL; > > unsigned int lookup_flags = 0; > > retry: > > name = user_path_parent(dfd, pathname, &nd, lookup_flags); > > @@ -3444,7 +3454,7 @@ retry: > > error = mnt_want_write(nd.path.mnt); > > if (error) > > goto exit1; > > - > > +retry_deleg: > > mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); > > dentry = lookup_hash(&nd); > > error = PTR_ERR(dentry); > > @@ -3459,13 +3469,21 @@ retry: > > error = security_path_unlink(&nd.path, dentry); > > if (error) > > goto exit2; > > - error = vfs_unlink(nd.path.dentry->d_inode, dentry); > > + error = vfs_unlink(nd.path.dentry->d_inode, dentry, &delegated_inode); > > exit2: > > dput(dentry); > > } > > mutex_unlock(&nd.path.dentry->d_inode->i_mutex); > > if (inode) > > iput(inode); /* truncate the inode here */ > > + inode = NULL; > > + if (delegated_inode) { > > + error = break_deleg(delegated_inode, O_WRONLY); > > + iput(delegated_inode); > > + delegated_inode = NULL; > > + if (!error) > > + goto retry_deleg; > > + } > > mnt_drop_write(nd.path.mnt); > > exit1: > > path_put(&nd.path); > > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c > > index 84ce601..6ccaca2 100644 > > --- a/fs/nfsd/vfs.c > > +++ b/fs/nfsd/vfs.c > > @@ -1882,7 +1882,7 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, > > if (host_err) > > goto out_put; > > if (type != S_IFDIR) > > - host_err = vfs_unlink(dirp, rdentry); > > + host_err = vfs_unlink(dirp, rdentry, NULL); > > else > > host_err = vfs_rmdir(dirp, rdentry); > > if (!host_err) > > diff --git a/include/linux/fs.h b/include/linux/fs.h > > index c6cc686..f951588 100644 > > --- a/include/linux/fs.h > > +++ b/include/linux/fs.h > > @@ -1463,7 +1463,7 @@ extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t); > > extern int vfs_symlink(struct inode *, struct dentry *, const char *); > > extern int vfs_link(struct dentry *, struct inode *, struct dentry *); > > extern int vfs_rmdir(struct inode *, struct dentry *); > > -extern int vfs_unlink(struct inode *, struct dentry *); > > +extern int vfs_unlink(struct inode *, struct dentry *, struct inode **); > > extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); > > > > /* > > diff --git a/ipc/mqueue.c b/ipc/mqueue.c > > index e4e47f6..384eb35 100644 > > --- a/ipc/mqueue.c > > +++ b/ipc/mqueue.c > > @@ -884,7 +884,7 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name) > > err = -ENOENT; > > } else { > > ihold(inode); > > - err = vfs_unlink(dentry->d_parent->d_inode, dentry); > > + err = vfs_unlink(dentry->d_parent->d_inode, dentry, NULL); > > } > > dput(dentry); > > > > We probably also ought to eyeball some of these other cases where you > passing in NULL as the deleg_inode too. It's probably reasonable in > most cases -- exporting a filesystem that you also mount using ecryptfs > seems silly, but you never know... > Looks reasonable otherwise, if a little convoluted. > My apologies -- one of my gripes with claws-mail is that "ctrl+return" is "Send", and I occasionally fat-finger it. Anyway... Acked-by: Jeff Layton <jlayton@redhat.com> -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Jul 09, 2013 at 09:05:06AM -0400, Jeff Layton wrote: > We probably also ought to eyeball some of these other cases where you > passing in NULL as the deleg_inode too. It's probably reasonable in > most cases -- exporting a filesystem that you also mount using ecryptfs > seems silly, but you never know... The cases in this patch: - devtmpfs, mqueue: not exportable - cachefiles, ecryptfs: probably nothing prevents exporting the underlying filesystem, but it sounds nuts. If somebody actually runs into this case, we'll error out--the kernel won't crash, the delegation won't be violated--and they can come to us and try to make the case why this is a problem. - nfsd: handles delegation breaks in its own way (by returning a DELAY error to the client and leaving it to the client to retry). --b. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c index 7413d06..1b8490e 100644 --- a/drivers/base/devtmpfs.c +++ b/drivers/base/devtmpfs.c @@ -324,7 +324,7 @@ static int handle_remove(const char *nodename, struct device *dev) mutex_lock(&dentry->d_inode->i_mutex); notify_change(dentry, &newattrs); mutex_unlock(&dentry->d_inode->i_mutex); - err = vfs_unlink(parent.dentry->d_inode, dentry); + err = vfs_unlink(parent.dentry->d_inode, dentry, NULL); if (!err || err == -ENOENT) deleted = 1; } diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index 8c01c5fc..d61d884 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -294,7 +294,7 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache, if (ret < 0) { cachefiles_io_error(cache, "Unlink security error"); } else { - ret = vfs_unlink(dir->d_inode, rep); + ret = vfs_unlink(dir->d_inode, rep, NULL); if (preemptive) cachefiles_mark_object_buried(cache, rep); diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 5eab400..af42d88 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -153,7 +153,7 @@ static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry, dget(lower_dentry); lower_dir_dentry = lock_parent(lower_dentry); - rc = vfs_unlink(lower_dir_inode, lower_dentry); + rc = vfs_unlink(lower_dir_inode, lower_dentry, NULL); if (rc) { printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc); goto out_unlock; diff --git a/fs/namei.c b/fs/namei.c index 7e76fe1..cba3db1 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3384,7 +3384,7 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname) return do_rmdir(AT_FDCWD, pathname); } -int vfs_unlink(struct inode *dir, struct dentry *dentry) +int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode) { struct inode *target = dentry->d_inode; int error = may_delete(dir, dentry, 0); @@ -3401,11 +3401,20 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry) else { error = security_inode_unlink(dir, dentry); if (!error) { + error = break_deleg(target, O_WRONLY|O_NONBLOCK); + if (error) { + if (error == -EWOULDBLOCK && delegated_inode) { + *delegated_inode = target; + ihold(target); + } + goto out; + } error = dir->i_op->unlink(dir, dentry); if (!error) dont_mount(dentry); } } +out: mutex_unlock(&target->i_mutex); /* We don't d_delete() NFS sillyrenamed files--they still exist. */ @@ -3430,6 +3439,7 @@ static long do_unlinkat(int dfd, const char __user *pathname) struct dentry *dentry; struct nameidata nd; struct inode *inode = NULL; + struct inode *delegated_inode = NULL; unsigned int lookup_flags = 0; retry: name = user_path_parent(dfd, pathname, &nd, lookup_flags); @@ -3444,7 +3454,7 @@ retry: error = mnt_want_write(nd.path.mnt); if (error) goto exit1; - +retry_deleg: mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); dentry = lookup_hash(&nd); error = PTR_ERR(dentry); @@ -3459,13 +3469,21 @@ retry: error = security_path_unlink(&nd.path, dentry); if (error) goto exit2; - error = vfs_unlink(nd.path.dentry->d_inode, dentry); + error = vfs_unlink(nd.path.dentry->d_inode, dentry, &delegated_inode); exit2: dput(dentry); } mutex_unlock(&nd.path.dentry->d_inode->i_mutex); if (inode) iput(inode); /* truncate the inode here */ + inode = NULL; + if (delegated_inode) { + error = break_deleg(delegated_inode, O_WRONLY); + iput(delegated_inode); + delegated_inode = NULL; + if (!error) + goto retry_deleg; + } mnt_drop_write(nd.path.mnt); exit1: path_put(&nd.path); diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 84ce601..6ccaca2 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1882,7 +1882,7 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, if (host_err) goto out_put; if (type != S_IFDIR) - host_err = vfs_unlink(dirp, rdentry); + host_err = vfs_unlink(dirp, rdentry, NULL); else host_err = vfs_rmdir(dirp, rdentry); if (!host_err) diff --git a/include/linux/fs.h b/include/linux/fs.h index c6cc686..f951588 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1463,7 +1463,7 @@ extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t); extern int vfs_symlink(struct inode *, struct dentry *, const char *); extern int vfs_link(struct dentry *, struct inode *, struct dentry *); extern int vfs_rmdir(struct inode *, struct dentry *); -extern int vfs_unlink(struct inode *, struct dentry *); +extern int vfs_unlink(struct inode *, struct dentry *, struct inode **); extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); /* diff --git a/ipc/mqueue.c b/ipc/mqueue.c index e4e47f6..384eb35 100644 --- a/ipc/mqueue.c +++ b/ipc/mqueue.c @@ -884,7 +884,7 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name) err = -ENOENT; } else { ihold(inode); - err = vfs_unlink(dentry->d_parent->d_inode, dentry); + err = vfs_unlink(dentry->d_parent->d_inode, dentry, NULL); } dput(dentry);