[RFC PATCH v2 03/13] KVM: guest_mem: Refactor out kvm_gmem_alloc_view()

[Ryan Afranji]

From: Ackerley Tng <ackerley...@google.com>

kvm_gmem_alloc_view() will allocate and build a file out of an inode.

Will be reused later by kvm_gmem_link()

Signed-off-by: Ackerley Tng <ackerley...@google.com>
Co-developed-by: Ryan Afranji <afra...@google.com>
Signed-off-by: Ryan Afranji <afra...@google.com>
---
 virt/kvm/guest_memfd.c | 61 +++++++++++++++++++-----------------------
 1 file changed, 27 insertions(+), 34 deletions(-)

diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
index 2ee26695dc31..a3918d1695b9 100644
--- a/virt/kvm/guest_memfd.c
+++ b/virt/kvm/guest_memfd.c
@@ -470,49 +470,47 @@ static struct inode 
*kvm_gmem_inode_make_secure_inode(const char *name,
        return inode;
 }
 
-static struct file *kvm_gmem_inode_create_getfile(void *priv, loff_t size,
-                                                 u64 flags)
+static struct file *kvm_gmem_alloc_view(struct kvm *kvm, struct inode *inode,
+                                    const char *name)
 {
-       static const char *name = "[kvm-gmem]";
-       struct inode *inode;
+       struct kvm_gmem *gmem;
        struct file *file;
-       int err;
 
-       err = -ENOENT;
        if (!try_module_get(kvm_gmem_fops.owner))
-               goto err;
+               return ERR_PTR(-ENOENT);
 
-       inode = kvm_gmem_inode_make_secure_inode(name, size, flags);
-       if (IS_ERR(inode)) {
-               err = PTR_ERR(inode);
+       gmem = kzalloc(sizeof(*gmem), GFP_KERNEL);
+       if (!gmem) {
+               file = ERR_PTR(-ENOMEM);
                goto err_put_module;
        }
 
        file = alloc_file_pseudo(inode, kvm_gmem_mnt, name, O_RDWR,
                                 &kvm_gmem_fops);
-       if (IS_ERR(file)) {
-               err = PTR_ERR(file);
-               goto err_put_inode;
-       }
+       if (IS_ERR(file))
+               goto err_gmem;
 
        file->f_flags |= O_LARGEFILE;
-       file->private_data = priv;
+       file->private_data = gmem;
+
+       kvm_get_kvm(kvm);
+       gmem->kvm = kvm;
+       xa_init(&gmem->bindings);
+       list_add(&gmem->entry, &file_inode(file)->i_mapping->i_private_list);
 
-out:
        return file;
 
-err_put_inode:
-       iput(inode);
+err_gmem:
+       kfree(gmem);
 err_put_module:
        module_put(kvm_gmem_fops.owner);
-err:
-       file = ERR_PTR(err);
-       goto out;
+       return file;
 }
 
 static int __kvm_gmem_create(struct kvm *kvm, loff_t size, u64 flags)
 {
-       struct kvm_gmem *gmem;
+       static const char *name = "[kvm-gmem]";
+       struct inode *inode;
        struct file *file;
        int fd, err;
 
@@ -520,28 +518,23 @@ static int __kvm_gmem_create(struct kvm *kvm, loff_t 
size, u64 flags)
        if (fd < 0)
                return fd;
 
-       gmem = kzalloc(sizeof(*gmem), GFP_KERNEL);
-       if (!gmem) {
-               err = -ENOMEM;
+       inode = kvm_gmem_inode_make_secure_inode(name, size, flags);
+       if (IS_ERR(inode)) {
+               err = PTR_ERR(inode);
                goto err_fd;
        }
 
-       file = kvm_gmem_inode_create_getfile(gmem, size, flags);
+       file = kvm_gmem_alloc_view(kvm, inode, name);
        if (IS_ERR(file)) {
                err = PTR_ERR(file);
-               goto err_gmem;
+               goto err_put_inode;
        }
 
-       kvm_get_kvm(kvm);
-       gmem->kvm = kvm;
-       xa_init(&gmem->bindings);
-       list_add(&gmem->entry, &file_inode(file)->i_mapping->i_private_list);
-
        fd_install(fd, file);
        return fd;
 
-err_gmem:
-       kfree(gmem);
+err_put_inode:
+       iput(inode);
 err_fd:
        put_unused_fd(fd);
        return err;
-- 
2.49.0.1101.gccaa498523-goog