Add dedicated inode structure (kvm_gmem_inode_info) and slab-allocated inode cache for guest memory backing, similar to how shmem handles inodes.
This adds the necessary allocation/destruction functions and prepares for upcoming guest_memfd NUMA policy support changes.
Signed-off-by: Shivank Garg shivankg@amd.com --- virt/kvm/guest_memfd.c | 51 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+)
diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index 159df462d193..5a1ce6f5e287 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -17,6 +17,15 @@ struct kvm_gmem { struct list_head entry; };
+struct kvm_gmem_inode_info { + struct inode vfs_inode; +}; + +static inline struct kvm_gmem_inode_info *KVM_GMEM_I(struct inode *inode) +{ + return container_of(inode, struct kvm_gmem_inode_info, vfs_inode); +} + /** * folio_file_pfn - like folio_file_page, but return a pfn. * @folio: The folio which contains this index. @@ -392,8 +401,33 @@ static struct file_operations kvm_gmem_fops = { .fallocate = kvm_gmem_fallocate, };
+static struct kmem_cache *kvm_gmem_inode_cachep; + +static struct inode *kvm_gmem_alloc_inode(struct super_block *sb) +{ + struct kvm_gmem_inode_info *info; + + info = alloc_inode_sb(sb, kvm_gmem_inode_cachep, GFP_KERNEL); + if (!info) + return NULL; + + return &info->vfs_inode; +} + +static void kvm_gmem_destroy_inode(struct inode *inode) +{ +} + +static void kvm_gmem_free_inode(struct inode *inode) +{ + kmem_cache_free(kvm_gmem_inode_cachep, KVM_GMEM_I(inode)); +} + static const struct super_operations kvm_gmem_super_operations = { .statfs = simple_statfs, + .alloc_inode = kvm_gmem_alloc_inode, + .destroy_inode = kvm_gmem_destroy_inode, + .free_inode = kvm_gmem_free_inode, };
static int kvm_gmem_init_fs_context(struct fs_context *fc) @@ -426,10 +460,26 @@ static int kvm_gmem_init_mount(void) return 0; }
+static void kvm_gmem_init_inode(void *foo) +{ + struct kvm_gmem_inode_info *info = foo; + + inode_init_once(&info->vfs_inode); +} + +static void kvm_gmem_init_inodecache(void) +{ + kvm_gmem_inode_cachep = kmem_cache_create("kvm_gmem_inode_cache", + sizeof(struct kvm_gmem_inode_info), + 0, SLAB_ACCOUNT, + kvm_gmem_init_inode); +} + int kvm_gmem_init(struct module *module) { kvm_gmem_fops.owner = module;
+ kvm_gmem_init_inodecache(); return kvm_gmem_init_mount(); }
@@ -437,6 +487,7 @@ void kvm_gmem_exit(void) { kern_unmount(kvm_gmem_mnt); kvm_gmem_mnt = NULL; + kmem_cache_destroy(kvm_gmem_inode_cachep); }
static int kvm_gmem_migrate_folio(struct address_space *mapping,