/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 *   Copyright (C) 2019 Samsung Electronics Co., Ltd.
 */

#ifndef __VFS_CACHE_H__
#define __VFS_CACHE_H__

#include <linux/file.h>
#include <linux/fs.h>
#include <linux/mutex.h>
#include <linux/rwsem.h>
#include <linux/spinlock.h>
#include <linux/idr.h>
#include <linux/workqueue.h>

#include "vfs.h"
#include "mgmt/share_config.h"

/* Windows style file permissions for extended response */
#define	FILE_GENERIC_ALL	0x1F01FF
#define	FILE_GENERIC_READ	0x120089
#define	FILE_GENERIC_WRITE	0x120116
#define	FILE_GENERIC_EXECUTE	0X1200a0

/*
 * Start volatile/persistent file id allocation at 1. A file id of 0 yields an
 * SMB2 FileId of {0, 0}, which clients (e.g. Windows, Samba) treat as a null
 * handle and never close, leaking the open on the server.
 */
#define KSMBD_START_FID		1
#define KSMBD_NO_FID		(INT_MAX)
#define SMB2_NO_FID		(0xFFFFFFFFFFFFFFFFULL)

struct ksmbd_conn;
struct ksmbd_session;

struct ksmbd_lock {
	struct file_lock *fl;
	struct ksmbd_conn *conn;
	struct list_head clist;
	struct list_head flist;
	struct list_head llist;
	unsigned int flags;
	int cmd;
	int zero_len;
	unsigned long long start;
	unsigned long long end;
};

struct stream {
	char *name;
	ssize_t size;
	loff_t pos;
};

struct ksmbd_inode {
	struct rw_semaphore		m_lock;
	atomic_t			m_count;
	atomic_t			op_count;
	/* opinfo count for streams */
	atomic_t			sop_count;
	struct dentry			*m_de;
	unsigned int			m_flags;
	struct hlist_node		m_hash;
	struct list_head		m_fp_list;
	struct list_head		m_op_list;
	struct oplock_info		*m_opinfo;
	__le32				m_fattr;
};

enum {
	FP_NEW = 0,
	FP_INITED,
	FP_CLOSED
};

/* Owner information for durable handle reconnect */
struct durable_owner {
	unsigned int uid;
	unsigned int gid;
	char *name;
};

#define KSMBD_LOCK_SEQ_ARRAY_SIZE	64

struct ksmbd_lock_sequence {
	bool				valid;
	u8				sequence;
};

struct ksmbd_file {
	struct file			*filp;
	u64				persistent_id;
	u64				volatile_id;
	u64				durable_volatile_id;

	spinlock_t			f_lock;

	struct ksmbd_inode		*f_ci;
	struct ksmbd_inode		*f_parent_ci;
	struct oplock_info __rcu	*f_opinfo;
	struct ksmbd_conn		*conn;
	struct ksmbd_tree_connect	*tcon;

	atomic_t			refcount;
	__le32				daccess;
	__le32				saccess;
	__le32				coption;
	__le32				cdoption;
	__le32				create_file_attributes;
	__u64				create_time;
	__u64				change_time;
	__u64				allocation_size;
	__u64				itime;
	__u64				open_mtime;

	bool				is_nt_open;
	bool				attrib_only;
	bool				allocation_size_set;

	char				client_guid[16];
	char				create_guid[16];
	char				app_instance_id[16];

	struct stream			stream;
	struct list_head		node;
	struct list_head		blocked_works;
	struct list_head		lock_list;
	/*
	 * Per-handle FileDispositionInformation delete-pending state for a
	 * stream handle -- separate from ksmbd_inode's inode-wide m_flags,
	 * which have no way to record which stream on a multi-stream file
	 * was actually marked for deletion. See ksmbd_fd_set_delete_pending().
	 */
	bool				stream_del_pending;

	unsigned int			durable_timeout;
	unsigned int			durable_scavenger_timeout;
	/* CREATE action returned when this durable handle was established. */
	__le32				create_action;

	/* if ls is happening on directory, below is valid*/
	struct ksmbd_readdir_data	readdir_data;
	struct mutex			readdir_lock;
	int				dot_dotdot[2];
	unsigned int			f_state;
	bool				reserve_lease_break;
	bool				is_durable;
	bool				is_persistent;
	bool				is_resilient;
	bool				has_app_instance_id;
	bool				app_instance_version_valid;
	u64				app_instance_version_high;
	u64				app_instance_version_low;
	bool				durable_reconnect_disabled;
	bool				durable_replay_consumed;

	bool                            is_posix_ctxt;
	struct durable_owner		owner;
	__le16				channel_sequence;
	unsigned int			outstanding_requests;
	unsigned int			outstanding_pre_requests;
	struct ksmbd_lock_sequence	lock_seq[KSMBD_LOCK_SEQ_ARRAY_SIZE];

	/*
	 * Pending CHANGE_NOTIFY completions for this handle, sent with
	 * STATUS_NOTIFY_CLEANUP when the handle is closed.
	 */
	struct list_head		notify_pendings;
};

static inline void set_ctx_actor(struct dir_context *ctx,
				 filldir_t actor)
{
	ctx->actor = actor;
}

#define KSMBD_NR_OPEN_DEFAULT BITS_PER_LONG

struct ksmbd_file_table {
	rwlock_t		lock;
	struct idr		*idr;
};

static inline bool has_file_id(u64 id)
{
	return id < KSMBD_NO_FID;
}

static inline bool ksmbd_stream_fd(struct ksmbd_file *fp)
{
	return fp->stream.name != NULL;
}

int ksmbd_init_file_table(struct ksmbd_file_table *ft);
void ksmbd_destroy_file_table(struct ksmbd_session *sess);
int ksmbd_close_fd(struct ksmbd_work *work, u64 id);
struct ksmbd_file *ksmbd_lookup_fd_fast(struct ksmbd_work *work, u64 id);
struct ksmbd_file *ksmbd_lookup_foreign_fd(struct ksmbd_work *work, u64 id);
struct ksmbd_file *ksmbd_lookup_fd_slow(struct ksmbd_work *work, u64 id,
					u64 pid);
int ksmbd_vfs_set_durable_owner(struct ksmbd_file *fp,
				struct ksmbd_user *user);
struct ksmbd_file *ksmbd_file_get(struct ksmbd_file *fp);
void ksmbd_fd_put(struct ksmbd_work *work, struct ksmbd_file *fp);
struct ksmbd_inode *ksmbd_inode_lookup_lock(struct dentry *d);
void ksmbd_inode_put(struct ksmbd_inode *ci);
bool ksmbd_close_disconnected_durable_delete_on_close(struct dentry *dentry);
struct ksmbd_file *ksmbd_lookup_global_fd(unsigned long long id);
struct ksmbd_file *ksmbd_lookup_durable_fd(unsigned long long id);
void ksmbd_put_durable_fd(struct ksmbd_file *fp);
int ksmbd_invalidate_durable_fd(unsigned long long id);
bool ksmbd_has_other_active_fd(struct ksmbd_file *fp);
bool ksmbd_has_stream_without_delete_share(struct ksmbd_file *fp);
struct ksmbd_file *ksmbd_lookup_fd_app_instance_id(char *app_instance_id);
int ksmbd_close_fd_app_instance_id(char *app_instance_id);
struct ksmbd_file *ksmbd_lookup_fd_cguid(char *cguid);
struct ksmbd_file *ksmbd_lookup_fd_inode(struct dentry *dentry);
bool ksmbd_has_other_nonposix_open(struct dentry *dentry);
bool ksmbd_has_nonposix_open_child(struct ksmbd_file *old_fp);
unsigned int ksmbd_open_durable_fd(struct ksmbd_file *fp);
struct ksmbd_file *ksmbd_open_fd(struct ksmbd_work *work, struct file *filp);
void ksmbd_launch_ksmbd_durable_scavenger(void);
void ksmbd_stop_durable_scavenger(void);
bool ksmbd_durable_scavenger_active(void);
void ksmbd_close_tree_conn_fds(struct ksmbd_work *work);
void ksmbd_close_session_fds(struct ksmbd_work *work);
void ksmbd_wake_session_blocked_works(struct ksmbd_session *sess);
int ksmbd_close_inode_fds(struct ksmbd_work *work, struct inode *inode);
int ksmbd_init_global_file_table(void);
void ksmbd_free_global_file_table(void);
void ksmbd_set_fd_limit(unsigned long limit);
int ksmbd_update_fstate(struct ksmbd_file_table *ft, struct ksmbd_file *fp,
			unsigned int state);
bool ksmbd_vfs_compare_durable_owner(struct ksmbd_file *fp,
		struct ksmbd_user *user);

/*
 * INODE hash
 */
int __init ksmbd_inode_hash_init(void);
void ksmbd_release_inode_hash(void);

enum KSMBD_INODE_STATUS {
	KSMBD_INODE_STATUS_OK,
	KSMBD_INODE_STATUS_UNKNOWN,
	KSMBD_INODE_STATUS_PENDING_DELETE,
};

int ksmbd_query_inode_status(struct dentry *dentry);
bool ksmbd_inode_pending_delete(struct ksmbd_file *fp);
void ksmbd_set_inode_pending_delete(struct ksmbd_file *fp);
void ksmbd_clear_inode_pending_delete(struct ksmbd_file *fp);
void ksmbd_fd_set_delete_on_close(struct ksmbd_file *fp,
				  int file_info);
void ksmbd_fd_set_delete_pending(struct ksmbd_file *fp);
void ksmbd_fd_clear_delete_pending(struct ksmbd_file *fp);
int ksmbd_reopen_durable_fd(struct ksmbd_work *work, struct ksmbd_file *fp);
int ksmbd_validate_name_reconnect(struct ksmbd_share_config *share,
				  struct ksmbd_file *fp, char *name);
int ksmbd_init_file_cache(void);
void ksmbd_exit_file_cache(void);
#endif /* __VFS_CACHE_H__ */