9p: implement i_op->atomic_open()

[platform/adaptation/renesas_rcar/renesas_kernel.git] / fs / 9p / vfs_inode_dotl.c

diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index a1e6c99..a354fe2 100644 (file)
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -68,24 +68,6 @@ static gid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
        return current_fsgid();
 }
 
-/**
- * v9fs_dentry_from_dir_inode - helper function to get the dentry from
- * dir inode.
- *
- */
-
-static struct dentry *v9fs_dentry_from_dir_inode(struct inode *inode)
-{
-       struct dentry *dentry;
-
-       spin_lock(&inode->i_lock);
-       /* Directory should have only one entry. */
-       BUG_ON(S_ISDIR(inode->i_mode) && !list_is_singular(&inode->i_dentry));
-       dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias);
-       spin_unlock(&inode->i_lock);
-       return dentry;
-}
-
 static int v9fs_test_inode_dotl(struct inode *inode, void *data)
 {
        struct v9fs_inode *v9inode = V9FS_I(inode);
@@ -248,7 +230,6 @@ int v9fs_open_to_dotl_flags(int flags)
  * @dir: directory inode that is being created
  * @dentry:  dentry that is being deleted
  * @mode: create permissions
- * @nd: path information
  *
  */
 
@@ -256,9 +237,16 @@ static int
 v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
                struct nameidata *nd)
 {
+       return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
+}
+
+static struct file *
+v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
+                         struct opendata *od, unsigned flags, umode_t omode,
+                         bool *created)
+{
        int err = 0;
        gid_t gid;
-       int flags;
        umode_t mode;
        char *name = NULL;
        struct file *filp;
@@ -269,19 +257,25 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
        struct p9_fid *dfid, *ofid, *inode_fid;
        struct v9fs_session_info *v9ses;
        struct posix_acl *pacl = NULL, *dacl = NULL;
+       struct dentry *res = NULL;
 
-       v9ses = v9fs_inode2v9ses(dir);
-       if (nd)
-               flags = nd->intent.open.flags;
-       else {
-               /*
-                * create call without LOOKUP_OPEN is due
-                * to mknod of regular files. So use mknod
-                * operation.
-                */
-               return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
+       if (d_unhashed(dentry)) {
+               res = v9fs_vfs_lookup(dir, dentry, NULL);
+               if (IS_ERR(res))
+                       return ERR_CAST(res);
+
+               if (res)
+                       dentry = res;
        }
 
+       /* Only creates */
+       if (!(flags & O_CREAT) || dentry->d_inode) {
+               finish_no_open(od, res);
+               return NULL;
+       }
+
+       v9ses = v9fs_inode2v9ses(dir);
+
        name = (char *) dentry->d_name.name;
        p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%hx\n",
                 name, flags, omode);
@@ -290,7 +284,7 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
        if (IS_ERR(dfid)) {
                err = PTR_ERR(dfid);
                p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
-               return err;
+               goto err_return;
        }
 
        /* clone a fid to use for creation */
@@ -298,7 +292,7 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
        if (IS_ERR(ofid)) {
                err = PTR_ERR(ofid);
                p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
-               return err;
+               goto err_return;
        }
 
        gid = v9fs_get_fsgid_for_create(dir);
@@ -363,7 +357,7 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
        }
        mutex_unlock(&v9inode->v_mutex);
        /* Since we are opening a file, assign the open fid to the file */
-       filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
+       filp = finish_open(od, dentry, generic_file_open);
        if (IS_ERR(filp)) {
                err = PTR_ERR(filp);
                goto err_clunk_old_fid;
@@ -373,7 +367,10 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
        if (v9ses->cache)
                v9fs_cache_inode_set_cookie(inode, filp);
 #endif
-       return 0;
+       *created = true;
+out:
+       dput(res);
+       return filp;
 
 error:
        if (fid)
@@ -382,7 +379,9 @@ err_clunk_old_fid:
        if (ofid)
                p9_client_clunk(ofid);
        v9fs_set_create_acl(NULL, &dacl, &pacl);
-       return err;
+err_return:
+       filp = ERR_PTR(err);
+       goto out;
 }
 
 /**
@@ -415,7 +414,7 @@ static int v9fs_vfs_mkdir_dotl(struct inode *dir,
        if (dir->i_mode & S_ISGID)
                omode |= S_ISGID;
 
-       dir_dentry = v9fs_dentry_from_dir_inode(dir);
+       dir_dentry = dentry->d_parent;
        dfid = v9fs_fid_lookup(dir_dentry);
        if (IS_ERR(dfid)) {
                err = PTR_ERR(dfid);
@@ -793,7 +792,7 @@ v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
                 dir->i_ino, old_dentry->d_name.name, dentry->d_name.name);
 
        v9ses = v9fs_inode2v9ses(dir);
-       dir_dentry = v9fs_dentry_from_dir_inode(dir);
+       dir_dentry = dentry->d_parent;
        dfid = v9fs_fid_lookup(dir_dentry);
        if (IS_ERR(dfid))
                return PTR_ERR(dfid);
@@ -858,7 +857,7 @@ v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
                return -EINVAL;
 
        v9ses = v9fs_inode2v9ses(dir);
-       dir_dentry = v9fs_dentry_from_dir_inode(dir);
+       dir_dentry = dentry->d_parent;
        dfid = v9fs_fid_lookup(dir_dentry);
        if (IS_ERR(dfid)) {
                err = PTR_ERR(dfid);
@@ -1000,6 +999,7 @@ out:
 
 const struct inode_operations v9fs_dir_inode_operations_dotl = {
        .create = v9fs_vfs_create_dotl,
+       .atomic_open = v9fs_vfs_atomic_open_dotl,
        .lookup = v9fs_vfs_lookup,
        .link = v9fs_vfs_link_dotl,
        .symlink = v9fs_vfs_symlink_dotl,