src/storage/f2fs/dir.h

// Copyright 2021 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef SRC_STORAGE_F2FS_DIR_H_
#define SRC_STORAGE_F2FS_DIR_H_

namespace f2fs {

extern const unsigned char kFiletypeTable[];

class Dir : public VnodeF2fs, public fbl::Recyclable<Dir> {
 public:
  explicit Dir(F2fs *fs, ino_t ino);

  // Required for memory management, see the class comment above Vnode for more.
  void fbl_recycle() { RecycleNode(); }

  // Lookup
  zx_status_t Lookup(std::string_view name, fbl::RefPtr<fs::Vnode> *out) final;
  zx_status_t DoLookup(std::string_view name, fbl::RefPtr<fs::Vnode> *out);
  DirEntry *FindEntryOnDevice(std::string_view name, fbl::RefPtr<Page> *res_page);
  DirEntry *FindEntry(std::string_view name, fbl::RefPtr<Page> *res_page);
  zx::status<DirEntry> FindEntry(std::string_view name);
  DirEntry *FindInInlineDir(std::string_view name, fbl::RefPtr<Page> *res_page);
  DirEntry *FindInBlock(fbl::RefPtr<Page> dentry_page, std::string_view name, uint64_t *max_slots,
                        f2fs_hash_t namehash, fbl::RefPtr<Page> *res_page);
  DirEntry *FindInLevel(unsigned int level, std::string_view name, f2fs_hash_t namehash,
                        fbl::RefPtr<Page> *res_page);
  zx_status_t Readdir(fs::VdirCookie *cookie, void *dirents, size_t len, size_t *out_actual) final;
  zx_status_t ReadInlineDir(fs::VdirCookie *cookie, void *dirents, size_t len, size_t *out_actual);

  // delete & set link
  zx_status_t Rename(fbl::RefPtr<fs::Vnode> _newdir, std::string_view oldname,
                     std::string_view newname, bool src_must_be_dir, bool dst_must_be_dir) final;
  void SetLink(DirEntry *de, fbl::RefPtr<Page> &page, VnodeF2fs *inode);
  DirEntry *ParentDir(fbl::RefPtr<Page> *out);
  DirEntry *ParentInlineDir(fbl::RefPtr<Page> *out);
  bool IsEmptyDir();
  bool IsEmptyInlineDir();
  zx::status<bool> IsSubdir(Dir *possible_dir);

  // create
  zx_status_t Link(std::string_view name, fbl::RefPtr<fs::Vnode> _target) final;
  zx_status_t Create(std::string_view name, uint32_t mode, fbl::RefPtr<fs::Vnode> *out) final;
  zx_status_t DoCreate(std::string_view name, uint32_t mode, fbl::RefPtr<fs::Vnode> *out);
  zx_status_t NewInode(uint32_t mode, fbl::RefPtr<VnodeF2fs> *out);
  zx_status_t Mkdir(std::string_view name, uint32_t mode, fbl::RefPtr<fs::Vnode> *out);
  zx_status_t AddLink(std::string_view name, VnodeF2fs *vnode);
  zx_status_t AddInlineEntry(std::string_view name, VnodeF2fs *vnode, bool *is_converted);
  unsigned int RoomInInlineDir(Page *ipage, int slots);
  zx_status_t ConvertInlineDir();
  int RoomForFilename(DentryBlock *dentry_blk, int slots);
  void UpdateParentMetadata(VnodeF2fs *inode, unsigned int current_depth);
  zx_status_t InitInodeMetadata(VnodeF2fs *vnode);
  zx_status_t MakeEmpty(VnodeF2fs *vnode);
  zx_status_t MakeEmptyInlineDir(VnodeF2fs *vnode);
  void InitDentInode(VnodeF2fs *vnode, NodePage *ipage);

  // delete
  zx_status_t Unlink(std::string_view name, bool must_be_dir) final;
  zx_status_t Rmdir(Dir *vnode, std::string_view name);
  zx_status_t DoUnlink(VnodeF2fs *vnode, std::string_view name);
  void DeleteEntry(DirEntry *dentry, fbl::RefPtr<Page> &page, VnodeF2fs *vnode);
  void DeleteInlineEntry(DirEntry *dentry, fbl::RefPtr<Page> &page, VnodeF2fs *vnode);

  // helper
  ino_t InodeByName(std::string_view name);
  bool IsMultimediaFile(VnodeF2fs &vnode, std::string_view sub);
  void SetColdFile(VnodeF2fs &vnode);
  block_t DirBlocks();
  static uint32_t DirBuckets(uint32_t level, uint8_t dir_level);
  static uint32_t BucketBlocks(uint32_t level);
  static uint64_t DirBlockIndex(uint32_t level, uint8_t dir_level, uint32_t idx);
  void SetDeType(DirEntry *de, VnodeF2fs *vnode);
  bool EarlyMatchName(std::string_view name, f2fs_hash_t namehash, const DirEntry &de);

  // inline helper
  uint32_t MaxInlineDentry() const;
  uint8_t *InlineDentryBitmap(Page *page);
  uint64_t InlineDentryBitmapSize() const;
  DirEntry *InlineDentryArray(Page *page);
  uint8_t (*InlineDentryFilenameArray(Page *page))[kDentrySlotLen];

#if 0  // porting needed
//   int F2fsSymlink(dentry *dentry, const char *symname);
//   int F2fsMknod(dentry *dentry, umode_t mode, dev_t rdev);
#endif
};

}  // namespace f2fs

#endif  // SRC_STORAGE_F2FS_DIR_H_