From 79714f72d3b964611997de512cb29198c9f2dbbb Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 15 Jun 2012 03:01:42 +0400 Subject: get rid of kern_path_parent() all callers want the same thing, actually - a kinda-sorta analog of kern_path_create(). I.e. they want parent vfsmount/dentry (with ->i_mutex held, to make sure the child dentry is still their child) + the child dentry. Signed-off-by Al Viro --- drivers/base/devtmpfs.c | 98 +++++++++++++++++++++---------------------------- 1 file changed, 41 insertions(+), 57 deletions(-) (limited to 'drivers/base/devtmpfs.c') diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c index 765c3a28077..d91a3a0b232 100644 --- a/drivers/base/devtmpfs.c +++ b/drivers/base/devtmpfs.c @@ -227,33 +227,24 @@ static int handle_create(const char *nodename, umode_t mode, struct device *dev) static int dev_rmdir(const char *name) { - struct nameidata nd; + struct path parent; struct dentry *dentry; int err; - err = kern_path_parent(name, &nd); - if (err) - return err; - - mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); - dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len); - if (!IS_ERR(dentry)) { - if (dentry->d_inode) { - if (dentry->d_inode->i_private == &thread) - err = vfs_rmdir(nd.path.dentry->d_inode, - dentry); - else - err = -EPERM; - } else { - err = -ENOENT; - } - dput(dentry); + dentry = kern_path_locked(name, &parent); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + if (dentry->d_inode) { + if (dentry->d_inode->i_private == &thread) + err = vfs_rmdir(parent.dentry->d_inode, dentry); + else + err = -EPERM; } else { - err = PTR_ERR(dentry); + err = -ENOENT; } - - mutex_unlock(&nd.path.dentry->d_inode->i_mutex); - path_put(&nd.path); + dput(dentry); + mutex_unlock(&parent.dentry->d_inode->i_mutex); + path_put(&parent); return err; } @@ -305,50 +296,43 @@ static int dev_mynode(struct device *dev, struct inode *inode, struct kstat *sta static int handle_remove(const char *nodename, struct device *dev) { - struct nameidata nd; + struct path parent; struct dentry *dentry; - struct kstat stat; int deleted = 1; int err; - err = kern_path_parent(nodename, &nd); - if (err) - return err; + dentry = kern_path_locked(nodename, &parent); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); - mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); - dentry = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len); - if (!IS_ERR(dentry)) { - if (dentry->d_inode) { - err = vfs_getattr(nd.path.mnt, dentry, &stat); - if (!err && dev_mynode(dev, dentry->d_inode, &stat)) { - struct iattr newattrs; - /* - * before unlinking this node, reset permissions - * of possible references like hardlinks - */ - newattrs.ia_uid = 0; - newattrs.ia_gid = 0; - newattrs.ia_mode = stat.mode & ~0777; - newattrs.ia_valid = - ATTR_UID|ATTR_GID|ATTR_MODE; - mutex_lock(&dentry->d_inode->i_mutex); - notify_change(dentry, &newattrs); - mutex_unlock(&dentry->d_inode->i_mutex); - err = vfs_unlink(nd.path.dentry->d_inode, - dentry); - if (!err || err == -ENOENT) - deleted = 1; - } - } else { - err = -ENOENT; + if (dentry->d_inode) { + struct kstat stat; + err = vfs_getattr(parent.mnt, dentry, &stat); + if (!err && dev_mynode(dev, dentry->d_inode, &stat)) { + struct iattr newattrs; + /* + * before unlinking this node, reset permissions + * of possible references like hardlinks + */ + newattrs.ia_uid = 0; + newattrs.ia_gid = 0; + newattrs.ia_mode = stat.mode & ~0777; + newattrs.ia_valid = + ATTR_UID|ATTR_GID|ATTR_MODE; + 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); + if (!err || err == -ENOENT) + deleted = 1; } - dput(dentry); } else { - err = PTR_ERR(dentry); + err = -ENOENT; } - mutex_unlock(&nd.path.dentry->d_inode->i_mutex); + dput(dentry); + mutex_unlock(&parent.dentry->d_inode->i_mutex); - path_put(&nd.path); + path_put(&parent); if (deleted && strchr(nodename, '/')) delete_path(nodename); return err; -- cgit v1.2.3-70-g09d2 From 921a1650de9eed40dd64d681aba4a4d98856f289 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 20 Jul 2012 01:15:31 +0400 Subject: new helper: done_path_create() releases what needs to be released after {kern,user}_path_create() Signed-off-by: Al Viro --- arch/powerpc/platforms/cell/spufs/syscalls.c | 4 +--- drivers/base/devtmpfs.c | 9 ++------- fs/namei.c | 24 ++++++++++++------------ fs/ocfs2/refcounttree.c | 4 +--- include/linux/namei.h | 1 + net/unix/af_unix.c | 9 ++++----- 6 files changed, 21 insertions(+), 30 deletions(-) (limited to 'drivers/base/devtmpfs.c') diff --git a/arch/powerpc/platforms/cell/spufs/syscalls.c b/arch/powerpc/platforms/cell/spufs/syscalls.c index 8591bb62d7f..5b7d8ffbf89 100644 --- a/arch/powerpc/platforms/cell/spufs/syscalls.c +++ b/arch/powerpc/platforms/cell/spufs/syscalls.c @@ -70,9 +70,7 @@ static long do_spu_create(const char __user *pathname, unsigned int flags, ret = PTR_ERR(dentry); if (!IS_ERR(dentry)) { ret = spufs_create(&path, dentry, flags, mode, neighbor); - mutex_unlock(&path.dentry->d_inode->i_mutex); - dput(dentry); - path_put(&path); + done_path_create(&path, dentry); } return ret; diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c index d91a3a0b232..deb4a456cf8 100644 --- a/drivers/base/devtmpfs.c +++ b/drivers/base/devtmpfs.c @@ -156,9 +156,7 @@ static int dev_mkdir(const char *name, umode_t mode) if (!err) /* mark as kernel-created inode */ dentry->d_inode->i_private = &thread; - dput(dentry); - mutex_unlock(&path.dentry->d_inode->i_mutex); - path_put(&path); + done_path_create(&path, dentry); return err; } @@ -218,10 +216,7 @@ static int handle_create(const char *nodename, umode_t mode, struct device *dev) /* mark as kernel-created inode */ dentry->d_inode->i_private = &thread; } - dput(dentry); - - mutex_unlock(&path.dentry->d_inode->i_mutex); - path_put(&path); + done_path_create(&path, dentry); return err; } diff --git a/fs/namei.c b/fs/namei.c index 2ccc35c4dc2..5bc6f3d1dc8 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2893,6 +2893,14 @@ out: } EXPORT_SYMBOL(kern_path_create); +void done_path_create(struct path *path, struct dentry *dentry) +{ + dput(dentry); + mutex_unlock(&path->dentry->d_inode->i_mutex); + path_put(path); +} +EXPORT_SYMBOL(done_path_create); + struct dentry *user_path_create(int dfd, const char __user *pathname, struct path *path, int is_dir) { char *tmp = getname(pathname); @@ -2989,9 +2997,7 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode, out_drop_write: mnt_drop_write(path.mnt); out_dput: - dput(dentry); - mutex_unlock(&path.dentry->d_inode->i_mutex); - path_put(&path); + done_path_create(&path, dentry); return error; } @@ -3048,9 +3054,7 @@ SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode) out_drop_write: mnt_drop_write(path.mnt); out_dput: - dput(dentry); - mutex_unlock(&path.dentry->d_inode->i_mutex); - path_put(&path); + done_path_create(&path, dentry); return error; } @@ -3334,9 +3338,7 @@ SYSCALL_DEFINE3(symlinkat, const char __user *, oldname, out_drop_write: mnt_drop_write(path.mnt); out_dput: - dput(dentry); - mutex_unlock(&path.dentry->d_inode->i_mutex); - path_put(&path); + done_path_create(&path, dentry); out_putname: putname(from); return error; @@ -3446,9 +3448,7 @@ SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, out_drop_write: mnt_drop_write(new_path.mnt); out_dput: - dput(new_dentry); - mutex_unlock(&new_path.dentry->d_inode->i_mutex); - path_put(&new_path); + done_path_create(&new_path, new_dentry); out: path_put(&old_path); diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c index 9f32d7cbb7a..23cf78f6850 100644 --- a/fs/ocfs2/refcounttree.c +++ b/fs/ocfs2/refcounttree.c @@ -4477,9 +4477,7 @@ int ocfs2_reflink_ioctl(struct inode *inode, new_dentry, preserve); mnt_drop_write(new_path.mnt); out_dput: - dput(new_dentry); - mutex_unlock(&new_path.dentry->d_inode->i_mutex); - path_put(&new_path); + done_path_create(&new_path, new_dentry); out: path_put(&old_path); diff --git a/include/linux/namei.h b/include/linux/namei.h index d2ef8b34b96..4bf19d8174e 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -67,6 +67,7 @@ extern int kern_path(const char *, unsigned, struct path *); extern struct dentry *kern_path_create(int, const char *, struct path *, int); extern struct dentry *user_path_create(int, const char __user *, struct path *, int); +extern void done_path_create(struct path *, struct dentry *); extern struct dentry *kern_path_locked(const char *, struct path *); extern int vfs_path_lookup(struct dentry *, struct vfsmount *, const char *, unsigned int, struct path *); diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 641f2e47f16..e8239540683 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -887,8 +887,9 @@ out_mknod_drop_write: mnt_drop_write(path.mnt); if (err) goto out_mknod_dput; - mutex_unlock(&path.dentry->d_inode->i_mutex); - dput(path.dentry); + mntget(path.mnt); + dget(dentry); + done_path_create(&path, dentry); path.dentry = dentry; addr->hash = UNIX_HASH_SIZE; @@ -923,9 +924,7 @@ out: return err; out_mknod_dput: - dput(dentry); - mutex_unlock(&path.dentry->d_inode->i_mutex); - path_put(&path); + done_path_create(&path, dentry); out_mknod_parent: if (err == -EEXIST) err = -EADDRINUSE; -- cgit v1.2.3-70-g09d2