make ->atomic_open() return int

Change of calling conventions:
old		new
NULL		1
file		0
ERR_PTR(-ve)	-ve

Caller *knows* that struct file *; no need to return it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

10 files changed, 90 insertions, 98 deletions

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index de626b3b342f..62ce8daefa95 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -856,7 +856,7 @@ error:
         return ERR_PTR(result);
 }
 
-static struct file *
+static int
 v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
                      struct opendata *od, unsigned flags, umode_t mode,
                      int *opened)
@@ -872,7 +872,7 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
         if (d_unhashed(dentry)) {
                 res = v9fs_vfs_lookup(dir, dentry, NULL);
                 if (IS_ERR(res))
-                        return ERR_CAST(res);
+                        return PTR_ERR(res);
 
                 if (res)
                         dentry = res;
@@ -881,7 +881,7 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
         /* Only creates */
         if (!(flags & O_CREAT) || dentry->d_inode) {
                 finish_no_open(od, res);
-                return NULL;
+                return 1;
         }
 
         err = 0;
@@ -933,13 +933,11 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
         *opened |= FILE_CREATED;
 out:
         dput(res);
-        return filp;
+        return err;
 
 error:
         if (fid)
                 p9_client_clunk(fid);
-
-        filp = ERR_PTR(err);
         goto out;
 }
 
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 3db55471bc93..69f05109f75d 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -240,7 +240,7 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
         return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
 }
 
-static struct file *
+static int
 v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
                           struct opendata *od, unsigned flags, umode_t omode,
                           int *opened)
@@ -262,7 +262,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
         if (d_unhashed(dentry)) {
                 res = v9fs_vfs_lookup(dir, dentry, NULL);
                 if (IS_ERR(res))
-                        return ERR_CAST(res);
+                        return PTR_ERR(res);
 
                 if (res)
                         dentry = res;
@@ -271,7 +271,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
         /* Only creates */
         if (!(flags & O_CREAT) || dentry->d_inode) {
                 finish_no_open(od, res);
-                return NULL;
+                return 1;
         }
 
         v9ses = v9fs_inode2v9ses(dir);
@@ -284,7 +284,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
         if (IS_ERR(dfid)) {
                 err = PTR_ERR(dfid);
                 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
-                goto err_return;
+                goto out;
         }
 
         /* clone a fid to use for creation */
@@ -292,7 +292,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
         if (IS_ERR(ofid)) {
                 err = PTR_ERR(ofid);
                 p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
-                goto err_return;
+                goto out;
         }
 
         gid = v9fs_get_fsgid_for_create(dir);
@@ -370,7 +370,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
         *opened |= FILE_CREATED;
 out:
         dput(res);
-        return filp;
+        return err;
 
 error:
         if (fid)
@@ -379,8 +379,6 @@ err_clunk_old_fid:
         if (ofid)
                 p9_client_clunk(ofid);
         v9fs_set_create_acl(NULL, &dacl, &pacl);
-err_return:
-        filp = ERR_PTR(err);
         goto out;
 }
 
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 81e5e908df9d..d8bfabeeaa25 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -634,21 +634,20 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
         return dentry;
 }
 
-struct file *ceph_atomic_open(struct inode *dir, struct dentry *dentry,
-                              struct opendata *od, unsigned flags, umode_t mode,
-                              int *opened)
+int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
+                     struct opendata *od, unsigned flags, umode_t mode,
+                     int *opened)
 {
         int err;
         struct dentry *res = NULL;
-        struct file *filp;
 
         if (!(flags & O_CREAT)) {
                 if (dentry->d_name.len > NAME_MAX)
-                        return ERR_PTR(-ENAMETOOLONG);
+                        return -ENAMETOOLONG;
 
                 err = ceph_init_dentry(dentry);
                 if (err < 0)
-                        return ERR_PTR(err);
+                        return err;
 
                 return ceph_lookup_open(dir, dentry, od, flags, mode, opened);
         }
@@ -656,7 +655,7 @@ struct file *ceph_atomic_open(struct inode *dir, struct dentry *dentry,
         if (d_unhashed(dentry)) {
                 res = ceph_lookup(dir, dentry, NULL);
                 if (IS_ERR(res))
-                        return ERR_CAST(res);
+                        return PTR_ERR(res);
 
                 if (res)
                         dentry = res;
@@ -665,14 +664,14 @@ struct file *ceph_atomic_open(struct inode *dir, struct dentry *dentry,
         /* We don't deal with positive dentries here */
         if (dentry->d_inode) {
                 finish_no_open(od, res);
-                return NULL;
+                return 1;
         }
 
         *opened |= FILE_CREATED;
-        filp = ceph_lookup_open(dir, dentry, od, flags, mode, opened);
+        err = ceph_lookup_open(dir, dentry, od, flags, mode, opened);
         dput(res);
 
-        return filp;
+        return err;
 }
 
 /*
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 4c304a90d046..b8cc3ee5401e 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -213,9 +213,9 @@ out:
  * may_open() fails, the struct *file gets cleaned up (i.e.
  * ceph_release gets called).  So fear not!
  */
-struct file *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
-                              struct opendata *od, unsigned flags, umode_t mode,
-                              int *opened)
+int ceph_lookup_open(struct inode *dir, struct dentry *dentry,
+                     struct opendata *od, unsigned flags, umode_t mode,
+                     int *opened)
 {
         struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
         struct ceph_mds_client *mdsc = fsc->mdsc;
@@ -230,7 +230,7 @@ struct file *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
         /* do the open */
         req = prepare_open_request(dir->i_sb, flags, mode);
         if (IS_ERR(req))
-                return ERR_CAST(req);
+                return PTR_ERR(req);
         req->r_dentry = dget(dentry);
         req->r_num_caps = 2;
         if (flags & O_CREAT) {
@@ -257,10 +257,10 @@ out:
         dout("ceph_lookup_open result=%p\n", ret);
 
         if (IS_ERR(ret))
-                return ERR_CAST(ret);
+                return PTR_ERR(ret);
 
         dput(ret);
-        return err ? ERR_PTR(err) : file;
+        return err;
 }
 
 int ceph_release(struct inode *inode, struct file *file)
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index f9a325108b49..f7e8e82ec47f 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -806,9 +806,9 @@ extern int ceph_copy_from_page_vector(struct page **pages,
                                     loff_t off, size_t len);
 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
 extern int ceph_open(struct inode *inode, struct file *file);
-extern struct file *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
-                                     struct opendata *od, unsigned flags,
-                                     umode_t mode, int *opened);
+extern int ceph_lookup_open(struct inode *dir, struct dentry *dentry,
+                             struct opendata *od, unsigned flags,
+                             umode_t mode, int *opened);
 extern int ceph_release(struct inode *inode, struct file *filp);
 
 /* dir.c */
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 92a7c3d8a031..58d9aca46a40 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -46,9 +46,9 @@ extern const struct inode_operations cifs_dir_inode_ops;
 extern struct inode *cifs_root_iget(struct super_block *);
 extern int cifs_create(struct inode *, struct dentry *, umode_t,
                        struct nameidata *);
-extern struct file *cifs_atomic_open(struct inode *, struct dentry *,
-                                     struct opendata *, unsigned, umode_t,
-                                     int *);
+extern int cifs_atomic_open(struct inode *, struct dentry *,
+                            struct opendata *, unsigned, umode_t,
+                            int *);
 extern struct dentry *cifs_lookup(struct inode *, struct dentry *,
                                   struct nameidata *);
 extern int cifs_unlink(struct inode *dir, struct dentry *dentry);
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 6cdf23fd70ee..8ca70b102b95 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -376,7 +376,7 @@ out:
         return rc;
 }
 
-struct file *
+int
 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
                  struct opendata *od, unsigned oflags, umode_t mode,
                  int *opened)
@@ -403,15 +403,15 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry,
         if (!(oflags & O_CREAT)) {
                 struct dentry *res = cifs_lookup(inode, direntry, NULL);
                 if (IS_ERR(res))
-                        return ERR_CAST(res);
+                        return PTR_ERR(res);
 
                 finish_no_open(od, res);
-                return NULL;
+                return 1;
         }
 
         rc = check_name(direntry);
         if (rc)
-                return ERR_PTR(rc);
+                return rc;
 
         xid = GetXid();
 
@@ -428,13 +428,12 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry,
         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
                             &oplock, &fileHandle, opened);
 
-        if (rc) {
-                filp = ERR_PTR(rc);
+        if (rc)
                 goto out;
-        }
 
         filp = finish_open(od, direntry, generic_file_open, opened);
         if (IS_ERR(filp)) {
+                rc = PTR_ERR(filp);
                 CIFSSMBClose(xid, tcon, fileHandle);
                 goto out;
         }
@@ -443,14 +442,14 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry,
         if (pfile_info == NULL) {
                 CIFSSMBClose(xid, tcon, fileHandle);
                 fput(filp);
-                filp = ERR_PTR(-ENOMEM);
+                rc = -ENOMEM;
         }
 
 out:
         cifs_put_tlink(tlink);
 free_xid:
         FreeXid(xid);
-        return filp;
+        return rc;
 }
 
 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 345f78ee5c9d..8a9ca09e87d4 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -369,9 +369,9 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
  * If the filesystem doesn't support this, then fall back to separate
  * 'mknod' + 'open' requests.
  */
-static struct file *fuse_create_open(struct inode *dir, struct dentry *entry,
-                                     struct opendata *od, unsigned flags,
-                                     umode_t mode, int *opened)
+static int fuse_create_open(struct inode *dir, struct dentry *entry,
+                            struct opendata *od, unsigned flags,
+                            umode_t mode, int *opened)
 {
         int err;
         struct inode *inode;
@@ -452,12 +452,14 @@ static struct file *fuse_create_open(struct inode *dir, struct dentry *entry,
         fuse_invalidate_attr(dir);
         file = finish_open(od, entry, generic_file_open, opened);
         if (IS_ERR(file)) {
+                err = PTR_ERR(file);
                 fuse_sync_release(ff, flags);
         } else {
                 file->private_data = fuse_file_get(ff);
                 fuse_finish_open(inode, file);
+                err = 0;
         }
-        return file;
+        return err;
 
 out_free_ff:
         fuse_file_free(ff);
@@ -466,23 +468,22 @@ out_put_request:
 out_put_forget_req:
         kfree(forget);
 out_err:
-        return ERR_PTR(err);
+        return err;
 }
 
 static int fuse_mknod(struct inode *, struct dentry *, umode_t, dev_t);
-static struct file *fuse_atomic_open(struct inode *dir, struct dentry *entry,
-                                     struct opendata *od, unsigned flags,
-                                     umode_t mode, int *opened)
+static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
+                            struct opendata *od, unsigned flags,
+                            umode_t mode, int *opened)
 {
         int err;
         struct fuse_conn *fc = get_fuse_conn(dir);
-        struct file *file;
         struct dentry *res = NULL;
 
         if (d_unhashed(entry)) {
                 res = fuse_lookup(dir, entry, NULL);
                 if (IS_ERR(res))
-                        return ERR_CAST(res);
+                        return PTR_ERR(res);
 
                 if (res)
                         entry = res;
@@ -497,24 +498,22 @@ static struct file *fuse_atomic_open(struct inode *dir, struct dentry *entry,
         if (fc->no_create)
                 goto mknod;
 
-        file = fuse_create_open(dir, entry, od, flags, mode, opened);
-        if (PTR_ERR(file) == -ENOSYS) {
+        err = fuse_create_open(dir, entry, od, flags, mode, opened);
+        if (err == -ENOSYS) {
                 fc->no_create = 1;
                 goto mknod;
         }
 out_dput:
         dput(res);
-        return file;
+        return err;
 
 mknod:
         err = fuse_mknod(dir, entry, mode, 0);
-        if (err) {
-                file = ERR_PTR(err);
+        if (err)
                 goto out_dput;
-        }
 no_open:
         finish_no_open(od, res);
-        return NULL;
+        return 1;
 }
 
 /*
diff --git a/fs/namei.c b/fs/namei.c
index 18b9326d951f..f0dae0057ec9 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2204,7 +2204,7 @@ static struct file *atomic_open(struct nameidata *nd, struct dentry *dentry,
         umode_t mode;
         int error;
         int acc_mode;
-        struct file *filp;
+        struct file *filp = NULL;
         int create_error = 0;
         struct dentry *const DENTRY_NOT_SET = (void *) -1UL;
 
@@ -2271,14 +2271,15 @@ static struct file *atomic_open(struct nameidata *nd, struct dentry *dentry,
 
         od->dentry = DENTRY_NOT_SET;
         od->mnt = nd->path.mnt;
-        filp = dir->i_op->atomic_open(dir, dentry, od, open_flag, mode,
+        error = dir->i_op->atomic_open(dir, dentry, od, open_flag, mode,
                                       opened);
-        if (IS_ERR(filp)) {
+        if (error < 0) {
                 if (WARN_ON(od->dentry != DENTRY_NOT_SET))
                         dput(od->dentry);
 
-                if (create_error && PTR_ERR(filp) == -ENOENT)
-                        filp = ERR_PTR(create_error);
+                if (create_error && error == -ENOENT)
+                        error = create_error;
+                filp = ERR_PTR(error);
                 goto out;
         }
 
@@ -2288,7 +2289,7 @@ static struct file *atomic_open(struct nameidata *nd, struct dentry *dentry,
                 acc_mode = MAY_OPEN;
         }
 
-        if (!filp) {
+        if (error) {    /* returned 1, that is */
                 if (WARN_ON(od->dentry == DENTRY_NOT_SET)) {
                         filp = ERR_PTR(-EIO);
                         goto out;
@@ -2304,6 +2305,7 @@ static struct file *atomic_open(struct nameidata *nd, struct dentry *dentry,
          * We didn't have the inode before the open, so check open permission
          * here.
          */
+        filp = od->filp;
         error = may_open(&filp->f_path, acc_mode, open_flag);
         if (error) {
                 fput(filp);
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 6deb2549ead5..b56f4b36ed41 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -111,9 +111,9 @@ const struct inode_operations nfs3_dir_inode_operations = {
 
 #ifdef CONFIG_NFS_V4
 
-static struct file *nfs_atomic_open(struct inode *, struct dentry *,
-                                    struct opendata *, unsigned, umode_t,
-                                    int *);
+static int nfs_atomic_open(struct inode *, struct dentry *,
+                           struct opendata *, unsigned, umode_t,
+                           int *);
 const struct inode_operations nfs4_dir_inode_operations = {
         .create         = nfs_create,
         .lookup         = nfs_lookup,
@@ -1387,10 +1387,10 @@ static int do_open(struct inode *inode, struct file *filp)
         return 0;
 }
 
-static struct file *nfs_finish_open(struct nfs_open_context *ctx,
-                                    struct dentry *dentry,
-                                    struct opendata *od, unsigned open_flags,
-                                    int *opened)
+static int nfs_finish_open(struct nfs_open_context *ctx,
+                           struct dentry *dentry,
+                           struct opendata *od, unsigned open_flags,
+                           int *opened)
 {
         struct file *filp;
         int err;
@@ -1403,30 +1403,31 @@ static struct file *nfs_finish_open(struct nfs_open_context *ctx,
         /* If the open_intent is for execute, we have an extra check to make */
         if (ctx->mode & FMODE_EXEC) {
                 err = nfs_may_open(dentry->d_inode, ctx->cred, open_flags);
-                if (err < 0) {
-                        filp = ERR_PTR(err);
+                if (err < 0)
                         goto out;
-                }
         }
 
         filp = finish_open(od, dentry, do_open, opened);
-        if (!IS_ERR(filp))
-                nfs_file_set_open_context(filp, ctx);
+        if (IS_ERR(filp)) {
+                err = PTR_ERR(filp);
+                goto out;
+        }
+        nfs_file_set_open_context(filp, ctx);
+        err = 0;
 
 out:
         put_nfs_open_context(ctx);
-        return filp;
+        return err;
 }
 
-static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
-                                    struct opendata *od, unsigned open_flags,
-                                    umode_t mode, int *opened)
+static int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
+                            struct opendata *od, unsigned open_flags,
+                            umode_t mode, int *opened)
 {
         struct nfs_open_context *ctx;
         struct dentry *res;
         struct iattr attr = { .ia_valid = ATTR_OPEN };
         struct inode *inode;
-        struct file *filp;
         int err;
 
         /* Expect a negative dentry */
@@ -1437,21 +1438,19 @@ static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
 
         /* NFS only supports OPEN on regular files */
         if ((open_flags & O_DIRECTORY)) {
-                err = -ENOENT;
                 if (!d_unhashed(dentry)) {
                         /*
                          * Hashed negative dentry with O_DIRECTORY: dentry was
                          * revalidated and is fine, no need to perform lookup
                          * again
                          */
-                        goto out_err;
+                        return -ENOENT;
                 }
                 goto no_open;
         }
 
-        err = -ENAMETOOLONG;
         if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
-                goto out_err;
+                return -ENAMETOOLONG;
 
         if (open_flags & O_CREAT) {
                 attr.ia_valid |= ATTR_MODE;
@@ -1465,7 +1464,7 @@ static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
         ctx = create_nfs_open_context(dentry, open_flags);
         err = PTR_ERR(ctx);
         if (IS_ERR(ctx))
-                goto out_err;
+                goto out;
 
         nfs_block_sillyrename(dentry->d_parent);
         inode = NFS_PROTO(dir)->open_context(dir, ctx, open_flags, &attr);
@@ -1489,7 +1488,7 @@ static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
                 default:
                         break;
                 }
-                goto out_err;
+                goto out;
         }
         res = d_add_unique(dentry, inode);
         if (res != NULL)
@@ -1498,22 +1497,20 @@ static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
         nfs_unblock_sillyrename(dentry->d_parent);
         nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 
-        filp = nfs_finish_open(ctx, dentry, od, open_flags, opened);
+        err = nfs_finish_open(ctx, dentry, od, open_flags, opened);
 
         dput(res);
-        return filp;
-
-out_err:
-        return ERR_PTR(err);
+out:
+        return err;
 
 no_open:
         res = nfs_lookup(dir, dentry, NULL);
         err = PTR_ERR(res);
         if (IS_ERR(res))
-                goto out_err;
+                goto out;
 
         finish_no_open(od, res);
-        return NULL;
+        return 1;
 }
 
 static int nfs4_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)