/* SPDX-License-Identifier: LGPL-2.1 */
/*
 *
 *   Copyright (C) International Business Machines  Corp., 2002,2008
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *              Jeremy Allison (jra@samba.org)
 *
 */
#ifndef _CIFS_GLOB_H
#define _CIFS_GLOB_H

#include <linux/in.h>
#include <linux/in6.h>
#include <linux/inet.h>
#include <linux/slab.h>
#include <linux/scatterlist.h>
#include <linux/mm.h>
#include <linux/mempool.h>
#include <linux/workqueue.h>
#include <linux/utsname.h>
#include <linux/sched/mm.h>
#include <linux/netfs.h>
#include <linux/fcntl.h>
#include "cifs_fs_sb.h"
#include "cifsacl.h"
#include <crypto/internal/hash.h>
#include <uapi/linux/cifs/cifs_mount.h>
#include "../common/smbglob.h"
#include "../common/smb2pdu.h"
#include "../common/fscc.h"
#include "smb2pdu.h"
#include "smb1pdu.h"
#include <linux/filelock.h>

#define SMB_PATH_MAX 260
#define CIFS_PORT 445
#define RFC1001_PORT 139

/*
 * The sizes of various internal tables and strings
 */
#define MAX_UID_INFO 16
#define MAX_SES_INFO 2
#define MAX_TCON_INFO 4

#define MAX_TREE_SIZE (2 + CIFS_NI_MAXHOST + 1 + CIFS_MAX_SHARE_LEN + 1)

#define CIFS_MIN_RCV_POOL 4

#define MAX_REOPEN_ATT  5 /* these many maximum attempts to reopen a file */
/*
 * default attribute cache timeout (jiffies)
 */
#define CIFS_DEF_ACTIMEO (1 * HZ)

/*
 * max sleep time before retry to server
 */
#define CIFS_MAX_SLEEP 2000

/*
 * max attribute cache timeout (jiffies) - 2^30
 */
#define CIFS_MAX_ACTIMEO (1 << 30)

/*
 * Max persistent and resilient handle timeout (milliseconds).
 * Windows durable max was 960000 (16 minutes)
 */
#define SMB3_MAX_HANDLE_TIMEOUT 960000

/*
 * MAX_REQ is the maximum number of requests that WE will send
 * on one socket concurrently.
 */
#define CIFS_MAX_REQ 32767

#define RFC1001_NAME_LEN 15
#define RFC1001_NAME_LEN_WITH_NULL (RFC1001_NAME_LEN + 1)

/* maximum length of ip addr as a string (including ipv6 and sctp) */
#define SERVER_NAME_LENGTH 80
#define SERVER_NAME_LEN_WITH_NULL     (SERVER_NAME_LENGTH + 1)

/* echo interval in seconds */
#define SMB_ECHO_INTERVAL_MIN 1
#define SMB_ECHO_INTERVAL_MAX 600
#define SMB_ECHO_INTERVAL_DEFAULT 60

/* smb multichannel query server interfaces interval in seconds */
#define SMB_INTERFACE_POLL_INTERVAL     600

/* maximum number of PDUs in one compound */
#define MAX_COMPOUND 10

/*
 * Default number of credits to keep available for SMB3.
 * This value is chosen somewhat arbitrarily. The Windows client
 * defaults to 128 credits, the Windows server allows clients up to
 * 512 credits (or 8K for later versions), and the NetApp server
 * does not limit clients at all.  Choose a high enough default value
 * such that the client shouldn't limit performance, but allow mount
 * to override (until you approach 64K, where we limit credits to 65000
 * to reduce possibility of seeing more server credit overflow bugs.
 */
#define SMB2_MAX_CREDITS_AVAILABLE 32000

#ifndef XATTR_DOS_ATTRIB
#define XATTR_DOS_ATTRIB "user.DOSATTRIB"
#endif

#define CIFS_MAX_WORKSTATION_LEN  (__NEW_UTS_LEN + 1)  /* reasonable max for client */

#define CIFS_DFS_ROOT_SES(ses) ((ses)->dfs_root_ses ?: (ses))

/*
 * CIFS vfs client Status information (based on what we know.)
 */

/* associated with each connection */
enum statusEnum {
        CifsNew = 0,
        CifsGood,
        CifsExiting,
        CifsNeedReconnect,
        CifsNeedNegotiate,
        CifsInNegotiate,
};

/* associated with each smb session */
enum ses_status_enum {
        SES_NEW = 0,
        SES_GOOD,
        SES_EXITING,
        SES_NEED_RECON,
        SES_IN_SETUP
};

/* associated with each tree connection to the server */
enum tid_status_enum {
        TID_NEW = 0,
        TID_GOOD,
        TID_EXITING,
        TID_NEED_RECON,
        TID_NEED_TCON,
        TID_IN_TCON,
        TID_NEED_FILES_INVALIDATE, /* currently unused */
        TID_IN_FILES_INVALIDATE
};

enum securityEnum {
        Unspecified = 0,        /* not specified */
        NTLMv2,                 /* Legacy NTLM auth with NTLMv2 hash */
        RawNTLMSSP,             /* NTLMSSP without SPNEGO, NTLMv2 hash */
        Kerberos,               /* Kerberos via SPNEGO */
        IAKerb,                 /* Kerberos proxy */
};

enum upcall_target_enum {
        UPTARGET_UNSPECIFIED, /* not specified, defaults to app */
        UPTARGET_MOUNT, /* upcall to the mount namespace */
        UPTARGET_APP, /* upcall to the application namespace which did the mount */
};

enum cifs_reparse_type {
        CIFS_REPARSE_TYPE_NONE,
        CIFS_REPARSE_TYPE_NFS,
        CIFS_REPARSE_TYPE_WSL,
        CIFS_REPARSE_TYPE_DEFAULT = CIFS_REPARSE_TYPE_NFS,
};

static inline const char *cifs_reparse_type_str(enum cifs_reparse_type type)
{
        switch (type) {
        case CIFS_REPARSE_TYPE_NONE:
                return "none";
        case CIFS_REPARSE_TYPE_NFS:
                return "nfs";
        case CIFS_REPARSE_TYPE_WSL:
                return "wsl";
        default:
                return "unknown";
        }
}

enum cifs_symlink_type {
        CIFS_SYMLINK_TYPE_DEFAULT,
        CIFS_SYMLINK_TYPE_NONE,
        CIFS_SYMLINK_TYPE_NATIVE,
        CIFS_SYMLINK_TYPE_UNIX,
        CIFS_SYMLINK_TYPE_MFSYMLINKS,
        CIFS_SYMLINK_TYPE_SFU,
        CIFS_SYMLINK_TYPE_NFS,
        CIFS_SYMLINK_TYPE_WSL,
};

static inline const char *cifs_symlink_type_str(enum cifs_symlink_type type)
{
        switch (type) {
        case CIFS_SYMLINK_TYPE_NONE:
                return "none";
        case CIFS_SYMLINK_TYPE_NATIVE:
                return "native";
        case CIFS_SYMLINK_TYPE_UNIX:
                return "unix";
        case CIFS_SYMLINK_TYPE_MFSYMLINKS:
                return "mfsymlinks";
        case CIFS_SYMLINK_TYPE_SFU:
                return "sfu";
        case CIFS_SYMLINK_TYPE_NFS:
                return "nfs";
        case CIFS_SYMLINK_TYPE_WSL:
                return "wsl";
        default:
                return "unknown";
        }
}

struct session_key {
        unsigned int len;
        char *response;
};

/* crypto hashing related structure/fields, not specific to a sec mech */
struct cifs_secmech {
        struct shash_desc *aes_cmac; /* block-cipher based MAC function, for SMB3 signatures */

        struct crypto_aead *enc; /* smb3 encryption AEAD TFM (AES-CCM and AES-GCM) */
        struct crypto_aead *dec; /* smb3 decryption AEAD TFM (AES-CCM and AES-GCM) */
};

/* per smb session structure/fields */
struct ntlmssp_auth {
        bool sesskey_per_smbsess; /* whether session key is per smb session */
        __u32 client_flags; /* sent by client in type 1 ntlmsssp exchange */
        __u32 server_flags; /* sent by server in type 2 ntlmssp exchange */
        unsigned char ciphertext[CIFS_CPHTXT_SIZE]; /* sent to server */
        char cryptkey[CIFS_CRYPTO_KEY_SIZE]; /* used by ntlmssp */
};

struct cifs_cred {
        int uid;
        int gid;
        int mode;
        int cecount;
        struct smb_sid osid;
        struct smb_sid gsid;
        struct cifs_ntace *ntaces;
        struct smb_ace *aces;
};

struct cifs_open_info_data {
        bool adjust_tz;
        bool reparse_point;
        bool contains_posix_file_info;
        struct {
                /* ioctl response buffer */
                struct {
                        int buftype;
                        struct kvec iov;
                } io;
                __u32 tag;
                struct reparse_data_buffer *buf;
        } reparse;
        struct {
                __u8            eas[SMB2_WSL_MAX_QUERY_EA_RESP_SIZE];
                unsigned int    eas_len;
        } wsl;
        char *symlink_target;
        struct smb_sid posix_owner;
        struct smb_sid posix_group;
        union {
                struct smb2_file_all_info fi;
                struct smb311_posix_qinfo posix_fi;
        };
};

/*
 *****************************************************************
 * Except the CIFS PDUs themselves all the
 * globally interesting structs should go here
 *****************************************************************
 */

/*
 * A smb_rqst represents a complete request to be issued to a server. It's
 * formed by a kvec array, followed by an array of pages. Page data is assumed
 * to start at the beginning of the first page.
 */
struct smb_rqst {
        struct kvec     *rq_iov;        /* array of kvecs */
        unsigned int    rq_nvec;        /* number of kvecs in array */
        struct iov_iter rq_iter;        /* Data iterator */
        struct folio_queue *rq_buffer;  /* Buffer for encryption */
};

struct mid_q_entry;
struct TCP_Server_Info;
struct cifsFileInfo;
struct cifs_ses;
struct cifs_tcon;
struct dfs_info3_param;
struct cifs_fattr;
struct smb3_fs_context;
struct cifs_fid;
struct cifs_io_subrequest;
struct cifs_io_parms;
struct cifs_search_info;
struct cifsInodeInfo;
struct cifs_open_parms;
struct cifs_credits;

struct smb_version_operations {
        int (*send_cancel)(struct cifs_ses *ses, struct TCP_Server_Info *server,
                           struct smb_rqst *rqst, struct mid_q_entry *mid,
                           unsigned int xid);
        bool (*compare_fids)(struct cifsFileInfo *, struct cifsFileInfo *);
        /* setup request: allocate mid, sign message */
        struct mid_q_entry *(*setup_request)(struct cifs_ses *,
                                             struct TCP_Server_Info *,
                                             struct smb_rqst *);
        /* setup async request: allocate mid, sign message */
        struct mid_q_entry *(*setup_async_request)(struct TCP_Server_Info *,
                                                struct smb_rqst *);
        /* check response: verify signature, map error */
        int (*check_receive)(struct mid_q_entry *, struct TCP_Server_Info *,
                             bool);
        void (*add_credits)(struct TCP_Server_Info *server,
                            struct cifs_credits *credits,
                            const int optype);
        void (*set_credits)(struct TCP_Server_Info *, const int);
        int * (*get_credits_field)(struct TCP_Server_Info *, const int);
        unsigned int (*get_credits)(struct mid_q_entry *);
        __u64 (*get_next_mid)(struct TCP_Server_Info *);
        void (*revert_current_mid)(struct TCP_Server_Info *server,
                                   const unsigned int val);
        /* data offset from read response message */
        unsigned int (*read_data_offset)(char *);
        /*
         * Data length from read response message
         * When in_remaining is true, the returned data length is in
         * message field DataRemaining for out-of-band data read (e.g through
         * Memory Registration RDMA write in SMBD).
         * Otherwise, the returned data length is in message field DataLength.
         */
        unsigned int (*read_data_length)(char *, bool in_remaining);
        /* map smb to linux error */
        int (*map_error)(char *, bool);
        /* find mid corresponding to the response message */
        struct mid_q_entry *(*find_mid)(struct TCP_Server_Info *server, char *buf);
        void (*dump_detail)(void *buf, size_t buf_len, struct TCP_Server_Info *ptcp_info);
        void (*clear_stats)(struct cifs_tcon *);
        void (*print_stats)(struct seq_file *m, struct cifs_tcon *);
        void (*dump_share_caps)(struct seq_file *, struct cifs_tcon *);
        /* verify the message */
        int (*check_message)(char *buf, unsigned int pdu_len, unsigned int len,
                             struct TCP_Server_Info *server);
        bool (*is_oplock_break)(char *, struct TCP_Server_Info *);
        int (*handle_cancelled_mid)(struct mid_q_entry *, struct TCP_Server_Info *);
        void (*downgrade_oplock)(struct TCP_Server_Info *server,
                                 struct cifsInodeInfo *cinode, __u32 oplock,
                                 __u16 epoch, bool *purge_cache);
        /* process transaction2 response */
        bool (*check_trans2)(struct mid_q_entry *, struct TCP_Server_Info *,
                             char *, int);
        /* check if we need to negotiate */
        bool (*need_neg)(struct TCP_Server_Info *);
        /* negotiate to the server */
        int (*negotiate)(const unsigned int xid,
                         struct cifs_ses *ses,
                         struct TCP_Server_Info *server);
        /* set negotiated write size */
        unsigned int (*negotiate_wsize)(struct cifs_tcon *tcon, struct smb3_fs_context *ctx);
        /* set negotiated read size */
        unsigned int (*negotiate_rsize)(struct cifs_tcon *tcon, struct smb3_fs_context *ctx);
        /* setup smb sessionn */
        int (*sess_setup)(const unsigned int, struct cifs_ses *,
                          struct TCP_Server_Info *server,
                          const struct nls_table *);
        /* close smb session */
        int (*logoff)(const unsigned int, struct cifs_ses *);
        /* connect to a server share */
        int (*tree_connect)(const unsigned int, struct cifs_ses *, const char *,
                            struct cifs_tcon *, const struct nls_table *);
        /* close tree connection */
        int (*tree_disconnect)(const unsigned int, struct cifs_tcon *);
        /* get DFS referrals */
        int (*get_dfs_refer)(const unsigned int, struct cifs_ses *,
                             const char *, struct dfs_info3_param **,
                             unsigned int *, const struct nls_table *, int);
        /* informational QFS call */
        void (*qfs_tcon)(const unsigned int, struct cifs_tcon *,
                         struct cifs_sb_info *);
        /* query for server interfaces */
        int (*query_server_interfaces)(const unsigned int, struct cifs_tcon *,
                                       bool);
        /* check if a path is accessible or not */
        int (*is_path_accessible)(const unsigned int, struct cifs_tcon *,
                                  struct cifs_sb_info *, const char *);
        /* query path data from the server */
        int (*query_path_info)(const unsigned int xid,
                               struct cifs_tcon *tcon,
                               struct cifs_sb_info *cifs_sb,
                               const char *full_path,
                               struct cifs_open_info_data *data);
        /* query file data from the server */
        int (*query_file_info)(const unsigned int xid, struct cifs_tcon *tcon,
                               struct cifsFileInfo *cfile, struct cifs_open_info_data *data);
        /* query reparse point to determine which type of special file */
        int (*query_reparse_point)(const unsigned int xid,
                                   struct cifs_tcon *tcon,
                                   struct cifs_sb_info *cifs_sb,
                                   const char *full_path,
                                   u32 *tag, struct kvec *rsp,
                                   int *rsp_buftype);
        /* get server index number */
        int (*get_srv_inum)(const unsigned int xid, struct cifs_tcon *tcon,
                            struct cifs_sb_info *cifs_sb, const char *full_path, u64 *uniqueid,
                            struct cifs_open_info_data *data);
        /* set size by path */
        int (*set_path_size)(const unsigned int, struct cifs_tcon *,
                             const char *, __u64, struct cifs_sb_info *, bool,
                                 struct dentry *);
        /* set size by file handle */
        int (*set_file_size)(const unsigned int, struct cifs_tcon *,
                             struct cifsFileInfo *, __u64, bool);
        /* set attributes */
        int (*set_file_info)(struct inode *, const char *, FILE_BASIC_INFO *,
                             const unsigned int);
        int (*set_compression)(const unsigned int, struct cifs_tcon *,
                               struct cifsFileInfo *);
        /* check if we can send an echo or nor */
        bool (*can_echo)(struct TCP_Server_Info *);
        /* send echo request */
        int (*echo)(struct TCP_Server_Info *);
        /* create directory */
        int (*posix_mkdir)(const unsigned int xid, struct inode *inode,
                        umode_t mode, struct cifs_tcon *tcon,
                        const char *full_path,
                        struct cifs_sb_info *cifs_sb);
        int (*mkdir)(const unsigned int xid, struct inode *inode, umode_t mode,
                     struct cifs_tcon *tcon, const char *name,
                     struct cifs_sb_info *sb);
        /* set info on created directory */
        void (*mkdir_setinfo)(struct inode *, const char *,
                              struct cifs_sb_info *, struct cifs_tcon *,
                              const unsigned int);
        /* remove directory */
        int (*rmdir)(const unsigned int, struct cifs_tcon *, const char *,
                     struct cifs_sb_info *);
        /* unlink file */
        int (*unlink)(const unsigned int, struct cifs_tcon *, const char *,
                      struct cifs_sb_info *, struct dentry *);
        /* open, rename and delete file */
        int (*rename_pending_delete)(const char *, struct dentry *,
                                     const unsigned int);
        /* send rename request */
        int (*rename)(const unsigned int xid,
                      struct cifs_tcon *tcon,
                      struct dentry *source_dentry,
                      const char *from_name, const char *to_name,
                      struct cifs_sb_info *cifs_sb);
        /* send create hardlink request */
        int (*create_hardlink)(const unsigned int xid,
                               struct cifs_tcon *tcon,
                               struct dentry *source_dentry,
                               const char *from_name, const char *to_name,
                               struct cifs_sb_info *cifs_sb);
        /* query symlink target */
        int (*query_symlink)(const unsigned int xid,
                             struct cifs_tcon *tcon,
                             struct cifs_sb_info *cifs_sb,
                             const char *full_path,
                             char **target_path);
        /* open a file for non-posix mounts */
        int (*open)(const unsigned int xid, struct cifs_open_parms *oparms, __u32 *oplock,
                    void *buf);
        /* set fid protocol-specific info */
        void (*set_fid)(struct cifsFileInfo *, struct cifs_fid *, __u32);
        /* close a file */
        int (*close)(const unsigned int, struct cifs_tcon *,
                      struct cifs_fid *);
        /* close a file, returning file attributes and timestamps */
        int (*close_getattr)(const unsigned int xid, struct cifs_tcon *tcon,
                      struct cifsFileInfo *pfile_info);
        /* send a flush request to the server */
        int (*flush)(const unsigned int, struct cifs_tcon *, struct cifs_fid *);
        /* async read from the server */
        int (*async_readv)(struct cifs_io_subrequest *);
        /* async write to the server */
        void (*async_writev)(struct cifs_io_subrequest *);
        /* sync read from the server */
        int (*sync_read)(const unsigned int, struct cifs_fid *,
                         struct cifs_io_parms *, unsigned int *, char **,
                         int *);
        /* sync write to the server */
        int (*sync_write)(const unsigned int, struct cifs_fid *,
                          struct cifs_io_parms *, unsigned int *, struct kvec *,
                          unsigned long);
        /* open dir, start readdir */
        int (*query_dir_first)(const unsigned int, struct cifs_tcon *,
                               const char *, struct cifs_sb_info *,
                               struct cifs_fid *, __u16,
                               struct cifs_search_info *);
        /* continue readdir */
        int (*query_dir_next)(const unsigned int, struct cifs_tcon *,
                              struct cifs_fid *,
                              __u16, struct cifs_search_info *srch_inf);
        /* close dir */
        int (*close_dir)(const unsigned int, struct cifs_tcon *,
                         struct cifs_fid *);
        /* calculate a size of SMB message */
        unsigned int (*calc_smb_size)(void *buf);
        /* check for STATUS_PENDING and process the response if yes */
        bool (*is_status_pending)(char *buf, struct TCP_Server_Info *server);
        /* check for STATUS_NETWORK_SESSION_EXPIRED */
        bool (*is_session_expired)(char *);
        /* send oplock break response */
        int (*oplock_response)(struct cifs_tcon *tcon, __u64 persistent_fid,
                               __u64 volatile_fid, __u16 net_fid,
                               struct cifsInodeInfo *cifs_inode,
                               unsigned int oplock);
        /* query remote filesystem */
        int (*queryfs)(const unsigned int, struct cifs_tcon *,
                       const char *, struct cifs_sb_info *, struct kstatfs *);
        /* send mandatory brlock to the server */
        int (*mand_lock)(const unsigned int, struct cifsFileInfo *, __u64,
                         __u64, __u32, int, int, bool);
        /* unlock range of mandatory locks */
        int (*mand_unlock_range)(struct cifsFileInfo *, struct file_lock *,
                                 const unsigned int);
        /* push brlocks from the cache to the server */
        int (*push_mand_locks)(struct cifsFileInfo *);
        /* get lease key of the inode */
        void (*get_lease_key)(struct inode *, struct cifs_fid *);
        /* set lease key of the inode */
        void (*set_lease_key)(struct inode *, struct cifs_fid *);
        /* generate new lease key */
        void (*new_lease_key)(struct cifs_fid *);
        int (*generate_signingkey)(struct cifs_ses *ses,
                                   struct TCP_Server_Info *server);
        int (*set_integrity)(const unsigned int, struct cifs_tcon *tcon,
                             struct cifsFileInfo *src_file);
        int (*enum_snapshots)(const unsigned int xid, struct cifs_tcon *tcon,
                             struct cifsFileInfo *src_file, void __user *);
        int (*notify)(const unsigned int xid, struct file *pfile,
                             void __user *pbuf, bool return_changes);
        int (*query_mf_symlink)(unsigned int, struct cifs_tcon *,
                                struct cifs_sb_info *, const unsigned char *,
                                char *, unsigned int *);
        int (*create_mf_symlink)(unsigned int, struct cifs_tcon *,
                                 struct cifs_sb_info *, const unsigned char *,
                                 char *, unsigned int *);
        /* if we can do cache read operations */
        bool (*is_read_op)(__u32);
        /* set oplock level for the inode */
        void (*set_oplock_level)(struct cifsInodeInfo *cinode, __u32 oplock, __u16 epoch,
                                 bool *purge_cache);
        /* create lease context buffer for CREATE request */
        char * (*create_lease_buf)(u8 *lease_key, u8 oplock, u8 *parent_lease_key, __le32 le_flags);
        /* parse lease context buffer and return oplock/epoch info */
        __u8 (*parse_lease_buf)(void *buf, __u16 *epoch, char *lkey);
        ssize_t (*copychunk_range)(const unsigned int,
                        struct cifsFileInfo *src_file,
                        struct cifsFileInfo *target_file,
                        u64 src_off, u64 len, u64 dest_off);
        int (*duplicate_extents)(const unsigned int, struct cifsFileInfo *src,
                        struct cifsFileInfo *target_file, u64 src_off, u64 len,
                        u64 dest_off);
        int (*validate_negotiate)(const unsigned int, struct cifs_tcon *);
        ssize_t (*query_all_EAs)(const unsigned int, struct cifs_tcon *,
                        const unsigned char *, const unsigned char *, char *,
                        size_t, struct cifs_sb_info *);
        int (*set_EA)(const unsigned int, struct cifs_tcon *, const char *,
                        const char *, const void *, const __u16,
                        const struct nls_table *, struct cifs_sb_info *);
        struct smb_ntsd * (*get_acl)(struct cifs_sb_info *cifssb, struct inode *ino,
                        const char *patch, u32 *plen, u32 info);
        struct smb_ntsd * (*get_acl_by_fid)(struct cifs_sb_info *cifssmb,
                        const struct cifs_fid *pfid, u32 *plen, u32 info);
        int (*set_acl)(struct smb_ntsd *pntsd, __u32 len, struct inode *ino, const char *path,
                        int flag);
        /* writepages retry size */
        unsigned int (*wp_retry_size)(struct inode *);
        /* get mtu credits */
        int (*wait_mtu_credits)(struct TCP_Server_Info *, size_t,
                                size_t *, struct cifs_credits *);
        /* adjust previously taken mtu credits to request size */
        int (*adjust_credits)(struct TCP_Server_Info *server,
                              struct cifs_io_subrequest *subreq,
                              unsigned int /*enum smb3_rw_credits_trace*/ trace);
        /* check if we need to issue closedir */
        bool (*dir_needs_close)(struct cifsFileInfo *);
        long (*fallocate)(struct file *, struct cifs_tcon *, int, loff_t,
                          loff_t);
        /* init transform (compress/encrypt) request */
        int (*init_transform_rq)(struct TCP_Server_Info *, int num_rqst,
                                 struct smb_rqst *, struct smb_rqst *);
        int (*is_transform_hdr)(void *buf);
        int (*receive_transform)(struct TCP_Server_Info *,
                                 struct mid_q_entry **, char **, int *);
        enum securityEnum (*select_sectype)(struct TCP_Server_Info *,
                            enum securityEnum);
        int (*next_header)(struct TCP_Server_Info *server, char *buf,
                           unsigned int *noff);
        /* ioctl passthrough for query_info */
        int (*ioctl_query_info)(const unsigned int xid,
                                struct cifs_tcon *tcon,
                                struct cifs_sb_info *cifs_sb,
                                __le16 *path, int is_dir,
                                unsigned long p);
        /* make unix special files (block, char, fifo, socket) */
        int (*make_node)(unsigned int xid,
                         struct inode *inode,
                         struct dentry *dentry,
                         struct cifs_tcon *tcon,
                         const char *full_path,
                         umode_t mode,
                         dev_t device_number);
        /* version specific fiemap implementation */
        int (*fiemap)(struct cifs_tcon *tcon, struct cifsFileInfo *,
                      struct fiemap_extent_info *, u64, u64);
        /* version specific llseek implementation */
        loff_t (*llseek)(struct file *, struct cifs_tcon *, loff_t, int);
        /* Check for STATUS_IO_TIMEOUT */
        bool (*is_status_io_timeout)(char *buf);
        /* Check for STATUS_NETWORK_NAME_DELETED */
        bool (*is_network_name_deleted)(char *buf, struct TCP_Server_Info *srv);
        struct reparse_data_buffer * (*get_reparse_point_buffer)(const struct kvec *rsp_iov,
                                                                 u32 *plen);
        struct inode * (*create_reparse_inode)(struct cifs_open_info_data *data,
                                               struct super_block *sb,
                                               const unsigned int xid,
                                               struct cifs_tcon *tcon,
                                               const char *full_path,
                                               bool directory,
                                               struct kvec *reparse_iov,
                                               struct kvec *xattr_iov);
};

#define HEADER_SIZE(server) (server->vals->header_size)
#define MAX_HEADER_SIZE(server) (server->vals->max_header_size)
#define MID_HEADER_SIZE(server) (HEADER_SIZE(server) - 1)

/**
 * CIFS superblock mount flags (mnt_cifs_flags) to consider when
 * trying to reuse existing superblock for a new mount
 */
#define CIFS_MOUNT_MASK (CIFS_MOUNT_NO_PERM | CIFS_MOUNT_SET_UID | \
                         CIFS_MOUNT_SERVER_INUM | CIFS_MOUNT_DIRECT_IO | \
                         CIFS_MOUNT_NO_XATTR | CIFS_MOUNT_MAP_SPECIAL_CHR | \
                         CIFS_MOUNT_MAP_SFM_CHR | \
                         CIFS_MOUNT_UNX_EMUL | CIFS_MOUNT_NO_BRL | \
                         CIFS_MOUNT_CIFS_ACL | CIFS_MOUNT_OVERR_UID | \
                         CIFS_MOUNT_OVERR_GID | CIFS_MOUNT_DYNPERM | \
                         CIFS_MOUNT_NOPOSIXBRL | CIFS_MOUNT_NOSSYNC | \
                         CIFS_MOUNT_FSCACHE | CIFS_MOUNT_MF_SYMLINKS | \
                         CIFS_MOUNT_MULTIUSER | CIFS_MOUNT_STRICT_IO | \
                         CIFS_MOUNT_CIFS_BACKUPUID | CIFS_MOUNT_CIFS_BACKUPGID | \
                         CIFS_MOUNT_UID_FROM_ACL | CIFS_MOUNT_NO_HANDLE_CACHE | \
                         CIFS_MOUNT_NO_DFS | CIFS_MOUNT_MODE_FROM_SID | \
                         CIFS_MOUNT_RO_CACHE | CIFS_MOUNT_RW_CACHE)

/**
 * Generic VFS superblock mount flags (s_flags) to consider when
 * trying to reuse existing superblock for a new mount
 */
#define CIFS_MS_MASK (SB_RDONLY | SB_MANDLOCK | SB_NOEXEC | SB_NOSUID | \
                      SB_NODEV | SB_SYNCHRONOUS)

struct cifs_mnt_data {
        struct cifs_sb_info *cifs_sb;
        struct smb3_fs_context *ctx;
        int flags;
};

struct TCP_Server_Info {
        struct list_head tcp_ses_list;
        struct list_head smb_ses_list;
        struct list_head rlist; /* reconnect list */
        spinlock_t srv_lock;  /* protect anything here that is not protected */
        __u64 conn_id; /* connection identifier (useful for debugging) */
        int srv_count; /* reference counter */
        int rfc1001_sessinit; /* whether to estasblish netbios session */
        bool with_rfc1001; /* if netbios session is used */
        /* 15 character server name + 0x20 16th byte indicating type = srv */
        char server_RFC1001_name[RFC1001_NAME_LEN_WITH_NULL];
        struct smb_version_operations   *ops;
        struct smb_version_values       *vals;
        /* updates to tcpStatus protected by cifs_tcp_ses_lock */
        enum statusEnum tcpStatus; /* what we think the status is */
        char *hostname; /* hostname portion of UNC string */
        struct socket *ssocket;
        struct sockaddr_storage dstaddr;
        struct sockaddr_storage srcaddr; /* locally bind to this IP */
#ifdef CONFIG_NET_NS
        struct net *net;
#endif
        wait_queue_head_t response_q;
        wait_queue_head_t request_q; /* if more than maxmpx to srvr must block*/
        spinlock_t mid_queue_lock;  /* protect mid queue */
        spinlock_t mid_counter_lock;
        struct list_head pending_mid_q;
        bool noblocksnd;                /* use blocking sendmsg */
        bool noautotune;                /* do not autotune send buf sizes */
        bool nosharesock;
        bool tcp_nodelay;
        bool terminate;
        int credits;  /* send no more requests at once */
        unsigned int max_credits; /* can override large 32000 default at mnt */
        unsigned int in_flight;  /* number of requests on the wire to server */
        unsigned int max_in_flight; /* max number of requests that were on wire */
        spinlock_t req_lock;  /* protect the two values above */
        struct mutex _srv_mutex;
        unsigned int nofs_flag;
        struct task_struct *tsk;
        char server_GUID[16];
        __u16 sec_mode;
        bool sign; /* is signing enabled on this connection? */
        bool ignore_signature:1; /* skip validation of signatures in SMB2/3 rsp */
        bool session_estab; /* mark when very first sess is established */
        int echo_credits;  /* echo reserved slots */
        int oplock_credits;  /* oplock break reserved slots */
        bool echoes:1; /* enable echoes */
        __u8 client_guid[SMB2_CLIENT_GUID_SIZE]; /* Client GUID */
        u16 dialect; /* dialect index that server chose */
        bool oplocks:1; /* enable oplocks */
        unsigned int maxReq;    /* Clients should submit no more */
        /* than maxReq distinct unanswered SMBs to the server when using  */
        /* multiplexed reads or writes (for SMB1/CIFS only, not SMB2/SMB3) */
        unsigned int maxBuf;    /* maxBuf specifies the maximum */
        /* message size the server can send or receive for non-raw SMBs */
        /* maxBuf is returned by SMB NegotiateProtocol so maxBuf is only 0 */
        /* when socket is setup (and during reconnect) before NegProt sent */
        unsigned int max_rw;    /* maxRw specifies the maximum */
        /* message size the server can send or receive for */
        /* SMB_COM_WRITE_RAW or SMB_COM_READ_RAW. */
        unsigned int capabilities; /* selective disabling of caps by smb sess */
        int timeAdj;  /* Adjust for difference in server time zone in sec */
        __u64 current_mid;      /* multiplex id - rotating counter, protected by mid_counter_lock */
        char cryptkey[CIFS_CRYPTO_KEY_SIZE]; /* used by ntlm, ntlmv2 etc */
        /* 16th byte of RFC1001 workstation name is always null */
        char workstation_RFC1001_name[RFC1001_NAME_LEN_WITH_NULL];
        __u32 sequence_number; /* for signing, protected by srv_mutex */
        __u32 reconnect_instance; /* incremented on each reconnect */
        __le32 session_key_id; /* retrieved from negotiate response and send in session setup request */
        struct session_key session_key;
        unsigned long lstrp; /* when we got last response from this server */
        unsigned long neg_start; /* when negotiate started (jiffies) */
        unsigned long reconn_delay; /* when resched session and tcon reconnect */
        struct cifs_secmech secmech; /* crypto sec mech functs, descriptors */
#define CIFS_NEGFLAVOR_UNENCAP  1       /* wct == 17, but no ext_sec */
#define CIFS_NEGFLAVOR_EXTENDED 2       /* wct == 17, ext_sec bit set */
        char    negflavor;      /* NEGOTIATE response flavor */
        /* extended security flavors that server supports */
        bool    sec_ntlmssp;            /* supports NTLMSSP */
        bool    sec_kerberosu2u;        /* supports U2U Kerberos */
        bool    sec_kerberos;           /* supports plain Kerberos */
        bool    sec_mskerberos;         /* supports legacy MS Kerberos */
        bool    sec_iakerb;             /* supports pass-through auth for Kerberos (krb5 proxy) */
        bool    large_buf;              /* is current buffer large? */
        /* use SMBD connection instead of socket */
        bool    rdma;
        /* point to the SMBD connection if RDMA is used instead of socket */
        struct smbd_connection *smbd_conn;
        struct delayed_work     echo; /* echo ping workqueue job */
        char    *smallbuf;      /* pointer to current "small" buffer */
        char    *bigbuf;        /* pointer to current "big" buffer */
        /* Total size of this PDU. Only valid from cifs_demultiplex_thread */
        unsigned int pdu_size;
        unsigned int total_read; /* total amount of data read in this pass */
        atomic_t in_send; /* requests trying to send */
        atomic_t num_waiters;   /* blocked waiting to get in sendrecv */
#ifdef CONFIG_CIFS_STATS2
        atomic_t num_cmds[NUMBER_OF_SMB2_COMMANDS]; /* total requests by cmd */
        atomic_t smb2slowcmd[NUMBER_OF_SMB2_COMMANDS]; /* count resps > 1 sec */
        __u64 time_per_cmd[NUMBER_OF_SMB2_COMMANDS]; /* total time per cmd */
        __u32 slowest_cmd[NUMBER_OF_SMB2_COMMANDS];
        __u32 fastest_cmd[NUMBER_OF_SMB2_COMMANDS];
#endif /* STATS2 */
        unsigned int    max_read;
        unsigned int    max_write;
        unsigned int    min_offload;
        /*
         * If payload is less than or equal to the threshold,
         * use RDMA send/recv to send upper layer I/O.
         * If payload is more than the threshold,
         * use RDMA read/write through memory registration for I/O.
         */
        unsigned int    rdma_readwrite_threshold;
        unsigned int    retrans;
        struct {
                bool requested; /* "compress" mount option set*/
                bool enabled; /* actually negotiated with server */
                __le16 alg; /* preferred alg negotiated with server */
        } compression;
        __u16   signing_algorithm;
        __le16  cipher_type;
         /* save initial negprot hash */
        __u8    preauth_sha_hash[SMB2_PREAUTH_HASH_SIZE];
        bool    signing_negotiated; /* true if valid signing context rcvd from server */
        bool    posix_ext_supported;
        struct delayed_work reconnect; /* reconnect workqueue job */
        struct mutex reconnect_mutex; /* prevent simultaneous reconnects */
        unsigned long echo_interval;

        /*
         * Number of targets available for reconnect. The more targets
         * the more tasks have to wait to let the demultiplex thread
         * reconnect.
         */
        int nr_targets;
        bool noblockcnt; /* use non-blocking connect() */

        /*
         * If this is a session channel,
         * primary_server holds the ref-counted
         * pointer to primary channel connection for the session.
         */
#define SERVER_IS_CHAN(server)  (!!(server)->primary_server)
        struct TCP_Server_Info *primary_server;
        __u16 channel_sequence_num;  /* incremented on primary channel on each chan reconnect */

#ifdef CONFIG_CIFS_SWN_UPCALL
        bool use_swn_dstaddr;
        struct sockaddr_storage swn_dstaddr;
#endif
        /*
         * Canonical DFS referral path used in cifs_reconnect() for failover as
         * well as in DFS cache refresher.
         *
         * format: \\HOST\SHARE[\OPTIONAL PATH]
         */
        char *leaf_fullpath;
        bool dfs_conn:1;
        char dns_dom[CIFS_MAX_DOMAINNAME_LEN + 1];
};

static inline bool is_smb1(const struct TCP_Server_Info *server)
{
        return server->vals->protocol_id == SMB10_PROT_ID;
}

static inline void cifs_server_lock(struct TCP_Server_Info *server)
{
        unsigned int nofs_flag = memalloc_nofs_save();

        mutex_lock(&server->_srv_mutex);
        server->nofs_flag = nofs_flag;
}

static inline void cifs_server_unlock(struct TCP_Server_Info *server)
{
        unsigned int nofs_flag = server->nofs_flag;

        mutex_unlock(&server->_srv_mutex);
        memalloc_nofs_restore(nofs_flag);
}

struct cifs_credits {
        unsigned int value;
        unsigned int instance;
        unsigned int in_flight_check;
        unsigned int rreq_debug_id;
        unsigned int rreq_debug_index;
};

static inline unsigned int
in_flight(struct TCP_Server_Info *server)
{
        unsigned int num;

        spin_lock(&server->req_lock);
        num = server->in_flight;
        spin_unlock(&server->req_lock);
        return num;
}

static inline bool
has_credits(struct TCP_Server_Info *server, int *credits, int num_credits)
{
        int num;

        spin_lock(&server->req_lock);
        num = *credits;
        spin_unlock(&server->req_lock);
        return num >= num_credits;
}

static inline void
add_credits(struct TCP_Server_Info *server, struct cifs_credits *credits,
            const int optype)
{
        server->ops->add_credits(server, credits, optype);
}

static inline void
add_credits_and_wake_if(struct TCP_Server_Info *server,
                        struct cifs_credits *credits, const int optype)
{
        if (credits->value) {
                server->ops->add_credits(server, credits, optype);
                wake_up(&server->request_q);
                credits->value = 0;
        }
}

static inline void
set_credits(struct TCP_Server_Info *server, const int val)
{
        server->ops->set_credits(server, val);
}

static inline int
adjust_credits(struct TCP_Server_Info *server, struct cifs_io_subrequest *subreq,
               unsigned int /* enum smb3_rw_credits_trace */ trace)
{
        return server->ops->adjust_credits ?
                server->ops->adjust_credits(server, subreq, trace) : 0;
}

static inline __le64
get_next_mid64(struct TCP_Server_Info *server)
{
        return cpu_to_le64(server->ops->get_next_mid(server));
}

static inline __le16
get_next_mid(struct TCP_Server_Info *server)
{
        __u16 mid = server->ops->get_next_mid(server);
        /*
         * The value in the SMB header should be little endian for easy
         * on-the-wire decoding.
         */
        return cpu_to_le16(mid);
}

static inline void
revert_current_mid(struct TCP_Server_Info *server, const unsigned int val)
{
        if (server->ops->revert_current_mid)
                server->ops->revert_current_mid(server, val);
}

static inline void
revert_current_mid_from_hdr(struct TCP_Server_Info *server,
                            const struct smb2_hdr *shdr)
{
        unsigned int num = le16_to_cpu(shdr->CreditCharge);

        return revert_current_mid(server, num > 0 ? num : 1);
}

/*
 * When the server supports very large reads and writes via POSIX extensions,
 * we can allow up to 2^24-1, minus the size of a READ/WRITE_AND_X header, not
 * including the RFC1001 length.
 *
 * Note that this might make for "interesting" allocation problems during
 * writeback however as we have to allocate an array of pointers for the
 * pages. A 16M write means ~32kb page array with PAGE_SIZE == 4096.
 *
 * For reads, there is a similar problem as we need to allocate an array
 * of kvecs to handle the receive, though that should only need to be done
 * once.
 */
#define CIFS_MAX_WSIZE ((1<<24) - 1 - sizeof(WRITE_REQ))
#define CIFS_MAX_RSIZE ((1<<24) - sizeof(READ_RSP))

/*
 * When the server doesn't allow large posix writes, only allow a rsize/wsize
 * of 2^17-1 minus the size of the call header. That allows for a read or
 * write up to the maximum size described by RFC1002.
 */
#define CIFS_MAX_RFC1002_WSIZE ((1<<17) - 1 - sizeof(WRITE_REQ))
#define CIFS_MAX_RFC1002_RSIZE ((1<<17) - 1 - sizeof(READ_RSP))

/*
 * Windows only supports a max of 60kb reads and 65535 byte writes. Default to
 * those values when posix extensions aren't in force. In actuality here, we
 * use 65536 to allow for a write that is a multiple of 4k. Most servers seem
 * to be ok with the extra byte even though Windows doesn't send writes that
 * are that large.
 *
 * Citation:
 *
 * https://blogs.msdn.com/b/openspecification/archive/2009/04/10/smb-maximum-transmit-buffer-size-and-performance-tuning.aspx
 */
#define CIFS_DEFAULT_NON_POSIX_RSIZE (60 * 1024)
#define CIFS_DEFAULT_NON_POSIX_WSIZE (65536)

/*
 * Macros to allow the TCP_Server_Info->net field and related code to drop out
 * when CONFIG_NET_NS isn't set.
 */

#ifdef CONFIG_NET_NS

static inline struct net *cifs_net_ns(struct TCP_Server_Info *srv)
{
        return srv->net;
}

static inline void cifs_set_net_ns(struct TCP_Server_Info *srv, struct net *net)
{
        srv->net = net;
}

#else

static inline struct net *cifs_net_ns(struct TCP_Server_Info *srv)
{
        return &init_net;
}

static inline void cifs_set_net_ns(struct TCP_Server_Info *srv, struct net *net)
{
}

#endif

struct cifs_server_iface {
        struct list_head iface_head;
        struct kref refcount;
        size_t speed;
        size_t weight_fulfilled;
        unsigned int num_channels;
        unsigned int rdma_capable : 1;
        unsigned int rss_capable : 1;
        unsigned int is_active : 1; /* unset if non existent */
        struct sockaddr_storage sockaddr;
};

/* release iface when last ref is dropped */
static inline void
release_iface(struct kref *ref)
{
        struct cifs_server_iface *iface = container_of(ref,
                                                       struct cifs_server_iface,
                                                       refcount);
        kfree(iface);
}

struct cifs_chan {
        unsigned int in_reconnect : 1; /* if session setup in progress for this channel */
        struct TCP_Server_Info *server;
        struct cifs_server_iface *iface; /* interface in use */
        __u8 signkey[SMB3_SIGN_KEY_SIZE];
};

#define CIFS_SES_FLAG_SCALE_CHANNELS (0x1)
#define CIFS_SES_FLAGS_PENDING_QUERY_INTERFACES (0x2)

/*
 * Session structure.  One of these for each uid session with a particular host
 */
struct cifs_ses {
        struct list_head smb_ses_list;
        struct list_head rlist; /* reconnect list */
        struct list_head tcon_list;
        struct list_head dlist; /* dfs list */
        struct cifs_tcon *tcon_ipc;
        spinlock_t ses_lock;  /* protect anything here that is not protected */
        struct mutex session_mutex;
        struct TCP_Server_Info *server; /* pointer to server info */
        int ses_count;          /* reference counter */
        enum ses_status_enum ses_status;  /* updates protected by cifs_tcp_ses_lock */
        unsigned int overrideSecFlg; /* if non-zero override global sec flags */
        char *serverOS;         /* name of operating system underlying server */
        char *serverNOS;        /* name of network operating system of server */
        char *serverDomain;     /* security realm of server */
        __u64 Suid;             /* remote smb uid  */
        kuid_t linux_uid;       /* overriding owner of files on the mount */
        kuid_t cred_uid;        /* owner of credentials */
        unsigned int capabilities;
        char ip_addr[INET6_ADDRSTRLEN + 1]; /* Max ipv6 (or v4) addr string len */
        char *user_name;        /* must not be null except during init of sess
                                   and after mount option parsing we fill it */
        char *domainName;
        char *password;
        char *password2; /* When key rotation used, new password may be set before it expires */
        char workstation_name[CIFS_MAX_WORKSTATION_LEN];
        struct session_key auth_key;
        struct ntlmssp_auth *ntlmssp; /* ciphertext, flags, server challenge */
        enum securityEnum sectype; /* what security flavor was specified? */
        enum upcall_target_enum upcall_target; /* what upcall target was specified? */
        bool sign;              /* is signing required? */
        bool domainAuto:1;
        bool expired_pwd;  /* track if access denied or expired pwd so can know if need to update */
        int unicode;
        unsigned int flags;
        __u16 session_flags;
        __u8 smb3signingkey[SMB3_SIGN_KEY_SIZE];
        __u8 smb3encryptionkey[SMB3_ENC_DEC_KEY_SIZE];
        __u8 smb3decryptionkey[SMB3_ENC_DEC_KEY_SIZE];
        __u8 preauth_sha_hash[SMB2_PREAUTH_HASH_SIZE];

        /*
         * Network interfaces available on the server this session is
         * connected to.
         *
         * Other channels can be opened by connecting and binding this
         * session to interfaces from this list.
         *
         * iface_lock should be taken when accessing any of these fields
         */
        spinlock_t iface_lock;
        /* ========= begin: protected by iface_lock ======== */
        struct list_head iface_list;
        size_t iface_count;
        unsigned long iface_last_update; /* jiffies */
        /* ========= end: protected by iface_lock ======== */

        spinlock_t chan_lock;
        /* ========= begin: protected by chan_lock ======== */
#define CIFS_MAX_CHANNELS 16
#define CIFS_INVAL_CHAN_INDEX (-1)
#define CIFS_ALL_CHANNELS_SET(ses)      \
        ((1UL << (ses)->chan_count) - 1)
#define CIFS_ALL_CHANS_GOOD(ses)                \
        (!(ses)->chans_need_reconnect)
#define CIFS_ALL_CHANS_NEED_RECONNECT(ses)      \
        ((ses)->chans_need_reconnect == CIFS_ALL_CHANNELS_SET(ses))
#define CIFS_SET_ALL_CHANS_NEED_RECONNECT(ses)  \
        ((ses)->chans_need_reconnect = CIFS_ALL_CHANNELS_SET(ses))
#define CIFS_CHAN_NEEDS_RECONNECT(ses, index)   \
        test_bit((index), &(ses)->chans_need_reconnect)
#define CIFS_CHAN_IN_RECONNECT(ses, index)      \
        ((ses)->chans[(index)].in_reconnect)

        struct cifs_chan chans[CIFS_MAX_CHANNELS];
        size_t chan_count;
        size_t chan_max;
        atomic_t chan_seq; /* round robin state */

        /*
         * chans_need_reconnect is a bitmap indicating which of the channels
         * under this smb session needs to be reconnected.
         * If not multichannel session, only one bit will be used.
         *
         * We will ask for sess and tcon reconnection only if all the
         * channels are marked for needing reconnection. This will
         * enable the sessions on top to continue to live till any
         * of the channels below are active.
         */
        unsigned long chans_need_reconnect;
        /* ========= end: protected by chan_lock ======== */
        struct cifs_ses *dfs_root_ses;
        struct nls_table *local_nls;
        char *dns_dom; /* FQDN of the domain */
};

static inline bool
cap_unix(struct cifs_ses *ses)
{
        return ses->server->vals->cap_unix & ses->capabilities;
}

/*
 * common struct for holding inode info when searching for or updating an
 * inode with new info
 */

#define CIFS_FATTR_JUNCTION             0x1
#define CIFS_FATTR_DELETE_PENDING       0x2
#define CIFS_FATTR_NEED_REVAL           0x4
#define CIFS_FATTR_INO_COLLISION        0x8
#define CIFS_FATTR_UNKNOWN_NLINK        0x10
#define CIFS_FATTR_FAKE_ROOT_INO        0x20

struct cifs_fattr {
        u32             cf_flags;
        u32             cf_cifsattrs;
        u64             cf_uniqueid;
        u64             cf_eof;
        u64             cf_bytes;
        u64             cf_createtime;
        kuid_t          cf_uid;
        kgid_t          cf_gid;
        umode_t         cf_mode;
        dev_t           cf_rdev;
        unsigned int    cf_nlink;
        unsigned int    cf_dtype;
        struct timespec64 cf_atime;
        struct timespec64 cf_mtime;
        struct timespec64 cf_ctime;
        u32             cf_cifstag;
        char            *cf_symlink_target;
};

/*
 * there is one of these for each connection to a resource on a particular
 * session
 */
struct cifs_tcon {
        struct list_head tcon_list;
        int debug_id;           /* Debugging for tracing */
        int tc_count;
        struct list_head rlist; /* reconnect list */
        spinlock_t tc_lock;  /* protect anything here that is not protected */
        atomic_t num_local_opens;  /* num of all opens including disconnected */
        atomic_t num_remote_opens; /* num of all network opens on server */
        struct list_head openFileList;
        spinlock_t open_file_lock; /* protects list above */
        struct cifs_ses *ses;   /* pointer to session associated with */
        char tree_name[MAX_TREE_SIZE + 1]; /* UNC name of resource in ASCII */
        char *nativeFileSystem;
        char *password;         /* for share-level security */
        __u32 tid;              /* The 4 byte tree id */
        __u16 Flags;            /* optional support bits */
        enum tid_status_enum status;
        atomic_t num_smbs_sent;
        union {
                struct {
                        atomic_t num_writes;
                        atomic_t num_reads;
                        atomic_t num_flushes;
                        atomic_t num_oplock_brks;
                        atomic_t num_opens;
                        atomic_t num_closes;
                        atomic_t num_deletes;
                        atomic_t num_mkdirs;
                        atomic_t num_posixopens;
                        atomic_t num_posixmkdirs;
                        atomic_t num_rmdirs;
                        atomic_t num_renames;
                        atomic_t num_t2renames;
                        atomic_t num_ffirst;
                        atomic_t num_fnext;
                        atomic_t num_fclose;
                        atomic_t num_hardlinks;
                        atomic_t num_symlinks;
                        atomic_t num_locks;
                        atomic_t num_acl_get;
                        atomic_t num_acl_set;
                } cifs_stats;
                struct {
                        atomic_t smb2_com_sent[NUMBER_OF_SMB2_COMMANDS];
                        atomic_t smb2_com_failed[NUMBER_OF_SMB2_COMMANDS];
                } smb2_stats;
        } stats;
        __u64    bytes_read;
        __u64    bytes_written;
        spinlock_t stat_lock;  /* protects the two fields above */
        time64_t stats_from_time;
        FILE_SYSTEM_DEVICE_INFO fsDevInfo;
        FILE_SYSTEM_ATTRIBUTE_INFO fsAttrInfo; /* ok if fs name truncated */
        FILE_SYSTEM_UNIX_INFO fsUnixInfo;
        bool ipc:1;   /* set if connection to IPC$ share (always also pipe) */
        bool pipe:1;  /* set if connection to pipe share */
        bool print:1; /* set if connection to printer share */
        bool retry:1;
        bool nocase:1;
        bool nohandlecache:1; /* if strange server resource prob can turn off */
        bool nodelete:1;
        bool seal:1;      /* transport encryption for this mounted share */
        bool unix_ext:1;  /* if false disable Linux extensions to CIFS protocol
                                for this mount even if server would support */
        bool posix_extensions; /* if true SMB3.11 posix extensions enabled */
        bool local_lease:1; /* check leases (only) on local system not remote */
        bool broken_posix_open; /* e.g. Samba server versions < 3.3.2, 3.2.9 */
        bool broken_sparse_sup; /* if server or share does not support sparse */
        bool need_reconnect:1; /* connection reset, tid now invalid */
        bool need_reopen_files:1; /* need to reopen tcon file handles */
        bool use_resilient:1; /* use resilient instead of durable handles */
        bool use_persistent:1; /* use persistent instead of durable handles */
        bool no_lease:1;    /* Do not request leases on files or directories */
        bool use_witness:1; /* use witness protocol */
        bool dummy:1; /* dummy tcon used for reconnecting channels */
        __le32 capabilities;
        __u32 share_flags;
        __u32 maximal_access;
        __u32 vol_serial_number;
        __le64 vol_create_time;
        __u64 snapshot_time; /* for timewarp tokens - timestamp of snapshot */
        __u32 handle_timeout; /* persistent and durable handle timeout in ms */
        __u32 ss_flags;         /* sector size flags */
        __u32 perf_sector_size; /* best sector size for perf */
        __u32 max_chunks;
        __u32 max_bytes_chunk;
        __u32 max_bytes_copy;
        __u32 max_cached_dirs;
#ifdef CONFIG_CIFS_FSCACHE
        u64 resource_id;                /* server resource id */
        bool fscache_acquired;          /* T if we've tried acquiring a cookie */
        struct fscache_volume *fscache; /* cookie for share */
        struct mutex fscache_lock;      /* Prevent regetting a cookie */
#endif
        struct list_head pending_opens; /* list of incomplete opens */
        struct cached_fids *cfids;
        struct list_head cifs_sb_list;
        spinlock_t sb_list_lock;
#ifdef CONFIG_CIFS_DFS_UPCALL
        struct delayed_work dfs_cache_work;
        struct list_head dfs_ses_list;
#endif
        struct delayed_work     query_interfaces; /* query interfaces workqueue job */
        char *origin_fullpath; /* canonical copy of smb3_fs_context::source */
};

/*
 * This is a refcounted and timestamped container for a tcon pointer. The
 * container holds a tcon reference. It is considered safe to free one of
 * these when the tl_count goes to 0. The tl_time is the time of the last
 * "get" on the container.
 */
struct tcon_link {
        struct rb_node          tl_rbnode;
        kuid_t                  tl_uid;
        unsigned long           tl_flags;
#define TCON_LINK_MASTER        0
#define TCON_LINK_PENDING       1
#define TCON_LINK_IN_TREE       2
        unsigned long           tl_time;
        atomic_t                tl_count;
        struct cifs_tcon        *tl_tcon;
};

struct tcon_link *cifs_sb_tlink(struct cifs_sb_info *cifs_sb);
void smb3_free_compound_rqst(int num_rqst, struct smb_rqst *rqst);

static inline struct cifs_tcon *
tlink_tcon(struct tcon_link *tlink)
{
        return tlink->tl_tcon;
}

static inline struct tcon_link *
cifs_sb_master_tlink(struct cifs_sb_info *cifs_sb)
{
        return cifs_sb->master_tlink;
}

void cifs_put_tlink(struct tcon_link *tlink);

static inline struct tcon_link *
cifs_get_tlink(struct tcon_link *tlink)
{
        if (tlink && !IS_ERR(tlink))
                atomic_inc(&tlink->tl_count);
        return tlink;
}

/* This function is always expected to succeed */
struct cifs_tcon *cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb);

#define CIFS_OPLOCK_NO_CHANGE 0xfe

struct cifs_pending_open {
        struct list_head olist;
        struct tcon_link *tlink;
        __u8 lease_key[16];
        __u32 oplock;
};

struct cifs_deferred_close {
        struct list_head dlist;
        struct tcon_link *tlink;
        __u16  netfid;
        __u64  persistent_fid;
        __u64  volatile_fid;
};

/*
 * This info hangs off the cifsFileInfo structure, pointed to by llist.
 * This is used to track byte stream locks on the file
 */
struct cifsLockInfo {
        struct list_head llist; /* pointer to next cifsLockInfo */
        struct list_head blist; /* pointer to locks blocked on this */
        wait_queue_head_t block_q;
        __u64 offset;
        __u64 length;
        __u32 pid;
        __u16 type;
        __u16 flags;
};

/*
 * One of these for each open instance of a file
 */
struct cifs_search_info {
        loff_t index_of_last_entry;
        __u16 entries_in_buffer;
        __u16 info_level;
        __u32 resume_key;
        char *ntwrk_buf_start;
        char *srch_entries_start;
        char *last_entry;
        const char *presume_name;
        unsigned int resume_name_len;
        bool endOfSearch:1;
        bool emptyDir:1;
        bool unicode:1;
        bool smallBuf:1; /* so we know which buf_release function to call */
};

#define ACL_NO_MODE     ((umode_t)(-1))
struct cifs_open_parms {
        struct cifs_tcon *tcon;
        struct cifs_sb_info *cifs_sb;
        int disposition;
        int desired_access;
        int create_options;
        const char *path;
        struct cifs_fid *fid;
        umode_t mode;
        bool reconnect:1;
        bool replay:1; /* indicates that this open is for a replay */
        struct kvec *ea_cctx;
        __le32 lease_flags;
};

struct cifs_fid {
        __u16 netfid;
        __u64 persistent_fid;   /* persist file id for smb2 */
        __u64 volatile_fid;     /* volatile file id for smb2 */
        __u8 lease_key[SMB2_LEASE_KEY_SIZE];    /* lease key for smb2 */
        __u8 parent_lease_key[SMB2_LEASE_KEY_SIZE];
        __u8 create_guid[16];
        __u32 access;
        struct cifs_pending_open *pending_open;
        __u16 epoch;
#ifdef CONFIG_CIFS_DEBUG2
        __u64 mid;
#endif /* CIFS_DEBUG2 */
        bool purge_cache;
};

struct cifs_fid_locks {
        struct list_head llist;
        struct cifsFileInfo *cfile;     /* fid that owns locks */
        struct list_head locks;         /* locks held by fid above */
};

struct cifsFileInfo {
        /* following two lists are protected by tcon->open_file_lock */
        struct list_head tlist; /* pointer to next fid owned by tcon */
        struct list_head flist; /* next fid (file instance) for this inode */
        /* lock list below protected by cifsi->lock_sem */
        struct cifs_fid_locks *llist;   /* brlocks held by this fid */
        kuid_t uid;             /* allows finding which FileInfo structure */
        __u32 pid;              /* process id who opened file */
        struct cifs_fid fid;    /* file id from remote */
        struct list_head rlist; /* reconnect list */
        /* BB add lock scope info here if needed */
        /* lock scope id (0 if none) */
        struct dentry *dentry;
        struct tcon_link *tlink;
        unsigned int f_flags;
        bool invalidHandle:1;   /* file closed via session abend */
        bool swapfile:1;
        bool oplock_break_cancelled:1;
        bool status_file_deleted:1; /* file has been deleted */
        bool offload:1; /* offload final part of _put to a wq */
        __u16 oplock_epoch; /* epoch from the lease break */
        __u32 oplock_level; /* oplock/lease level from the lease break */
        int count;
        spinlock_t file_info_lock; /* protects four flag/count fields above */
        struct mutex fh_mutex; /* prevents reopen race after dead ses*/
        struct cifs_search_info srch_inf;
        struct work_struct oplock_break; /* work for oplock breaks */
        struct work_struct put; /* work for the final part of _put */
        struct work_struct serverclose; /* work for serverclose */
        struct delayed_work deferred;
        bool deferred_close_scheduled; /* Flag to indicate close is scheduled */
        char *symlink_target;
};

struct cifs_io_parms {
        __u16 netfid;
        __u64 persistent_fid;   /* persist file id for smb2 */
        __u64 volatile_fid;     /* volatile file id for smb2 */
        __u32 pid;
        __u64 offset;
        unsigned int length;
        struct cifs_tcon *tcon;
        struct TCP_Server_Info *server;
};

struct cifs_io_request {
        struct netfs_io_request         rreq;
        struct cifsFileInfo             *cfile;
        pid_t                           pid;
};

/* asynchronous read support */
struct cifs_io_subrequest {
        union {
                struct netfs_io_subrequest subreq;
                struct netfs_io_request *rreq;
                struct cifs_io_request *req;
        };
        ssize_t                         got_bytes;
        unsigned int                    xid;
        int                             result;
        bool                            have_xid;
        bool                            replay;
        unsigned int                    retries;        /* number of retries so far */
        unsigned int                    cur_sleep;      /* time to sleep before replay */
        struct kvec                     iov[2];
        struct TCP_Server_Info          *server;
#ifdef CONFIG_CIFS_SMB_DIRECT
        struct smbdirect_mr_io          *mr;
#endif
        struct cifs_credits             credits;
};

/*
 * Take a reference on the file private data. Must be called with
 * cfile->file_info_lock held.
 */
static inline void
cifsFileInfo_get_locked(struct cifsFileInfo *cifs_file)
{
        ++cifs_file->count;
}

struct cifsFileInfo *cifsFileInfo_get(struct cifsFileInfo *cifs_file);
void _cifsFileInfo_put(struct cifsFileInfo *cifs_file,
                       bool wait_oplock_handler, bool offload);
void cifsFileInfo_put(struct cifsFileInfo *cifs_file);
int cifs_file_flush(const unsigned int xid, struct inode *inode,
                    struct cifsFileInfo *cfile);
int cifs_file_set_size(const unsigned int xid, struct dentry *dentry,
                       const char *full_path, struct cifsFileInfo *open_file,
                       loff_t size);

#define CIFS_CACHE_READ_FLG     1
#define CIFS_CACHE_HANDLE_FLG   2
#define CIFS_CACHE_RH_FLG       (CIFS_CACHE_READ_FLG | CIFS_CACHE_HANDLE_FLG)
#define CIFS_CACHE_WRITE_FLG    4
#define CIFS_CACHE_RW_FLG       (CIFS_CACHE_READ_FLG | CIFS_CACHE_WRITE_FLG)
#define CIFS_CACHE_RHW_FLG      (CIFS_CACHE_RW_FLG | CIFS_CACHE_HANDLE_FLG)

/*
 * One of these for each file inode
 */

struct cifsInodeInfo {
        struct netfs_inode netfs; /* Netfslib context and vfs inode */
        bool can_cache_brlcks;
        struct list_head llist; /* locks helb by this inode */
        /*
         * NOTE: Some code paths call down_read(lock_sem) twice, so
         * we must always use cifs_down_write() instead of down_write()
         * for this semaphore to avoid deadlocks.
         */
        struct rw_semaphore lock_sem;   /* protect the fields above */
        /* BB add in lists for dirty pages i.e. write caching info for oplock */
        struct list_head openFileList;
        spinlock_t      open_file_lock; /* protects openFileList */
        __u32 cifsAttrs; /* e.g. DOS archive bit, sparse, compressed, system */
        unsigned int oplock;            /* oplock/lease level we have */
        __u16 epoch;            /* used to track lease state changes */
#define CIFS_INODE_PENDING_OPLOCK_BREAK   (0) /* oplock break in progress */
#define CIFS_INODE_PENDING_WRITERS        (1) /* Writes in progress */
#define CIFS_INODE_FLAG_UNUSED            (2) /* Unused flag */
#define CIFS_INO_DELETE_PENDING           (3) /* delete pending on server */
#define CIFS_INO_INVALID_MAPPING          (4) /* pagecache is invalid */
#define CIFS_INO_LOCK                     (5) /* lock bit for synchronization */
#define CIFS_INO_CLOSE_ON_LOCK            (7) /* Not to defer the close when lock is set */
        unsigned long flags;
        spinlock_t writers_lock;
        unsigned int writers;           /* Number of writers on this inode */
        unsigned long time;             /* jiffies of last update of inode */
        u64  uniqueid;                  /* server inode number */
        u64  createtime;                /* creation time on server */
        __u8 lease_key[SMB2_LEASE_KEY_SIZE];    /* lease key for this inode */
        struct list_head deferred_closes; /* list of deferred closes */
        spinlock_t deferred_lock; /* protection on deferred list */
        bool lease_granted; /* Flag to indicate whether lease or oplock is granted. */
        char *symlink_target;
        __u32 reparse_tag;
};

static inline struct cifsInodeInfo *
CIFS_I(struct inode *inode)
{
        return container_of(inode, struct cifsInodeInfo, netfs.inode);
}

static inline void *cinode_to_fsinfo(struct cifsInodeInfo *cinode)
{
        return cinode->netfs.inode.i_sb->s_fs_info;
}

static inline void *super_to_fsinfo(struct super_block *sb)
{
        return sb->s_fs_info;
}

static inline void *inode_to_fsinfo(struct inode *inode)
{
        return inode->i_sb->s_fs_info;
}

static inline void *file_to_fsinfo(struct file *file)
{
        return file_inode(file)->i_sb->s_fs_info;
}

static inline void *dentry_to_fsinfo(struct dentry *dentry)
{
        return dentry->d_sb->s_fs_info;
}

static inline void *const_dentry_to_fsinfo(const struct dentry *dentry)
{
        return dentry->d_sb->s_fs_info;
}

#define CIFS_SB(_ptr) \
        ((struct cifs_sb_info *) \
         _Generic((_ptr), \
                  struct cifsInodeInfo * : cinode_to_fsinfo, \
                  const struct dentry * : const_dentry_to_fsinfo, \
                  struct super_block * : super_to_fsinfo, \
                  struct dentry * : dentry_to_fsinfo, \
                  struct inode * : inode_to_fsinfo, \
                  struct file * : file_to_fsinfo)(_ptr))

/*
 * Use atomic_t for @cifs_sb->mnt_cifs_flags as it is currently accessed
 * locklessly and may be changed concurrently by mount/remount and reconnect
 * paths.
 */
static inline unsigned int cifs_sb_flags(const struct cifs_sb_info *cifs_sb)
{
        return atomic_read(&cifs_sb->mnt_cifs_flags);
}

static inline char CIFS_DIR_SEP(const struct cifs_sb_info *cifs_sb)
{
        return (cifs_sb_flags(cifs_sb) & CIFS_MOUNT_POSIX_PATHS) ? '/' : '\\';
}

static inline void
convert_delimiter(char *path, char delim)
{
        char old_delim, *pos;

        if (delim == '/')
                old_delim = '\\';
        else
                old_delim = '/';

        pos = path;
        while ((pos = strchr(pos, old_delim)))
                *pos = delim;
}

#define cifs_stats_inc atomic_inc

static inline void cifs_stats_bytes_written(struct cifs_tcon *tcon,
                                            unsigned int bytes)
{
        if (bytes) {
                spin_lock(&tcon->stat_lock);
                tcon->bytes_written += bytes;
                spin_unlock(&tcon->stat_lock);
        }
}

static inline void cifs_stats_bytes_read(struct cifs_tcon *tcon,
                                         unsigned int bytes)
{
        spin_lock(&tcon->stat_lock);
        tcon->bytes_read += bytes;
        spin_unlock(&tcon->stat_lock);
}


/*
 * This is the prototype for the mid receive function. This function is for
 * receiving the rest of the SMB frame, starting with the WordCount (which is
 * just after the MID in struct smb_hdr). Note:
 *
 * - This will be called by cifsd, with no locks held.
 * - The mid will still be on the pending_mid_q.
 * - mid->resp_buf will point to the current buffer.
 *
 * Returns zero on a successful receive, or an error. The receive state in
 * the TCP_Server_Info will also be updated.
 */
typedef int (*mid_receive_t)(struct TCP_Server_Info *server,
                            struct mid_q_entry *mid);

/*
 * This is the prototype for the mid callback function. This is called once the
 * mid has been received off of the socket. When creating one, take special
 * care to avoid deadlocks. Things to bear in mind:
 *
 * - it will be called by cifsd, with no locks held
 * - the mid will be removed from any lists
 */
typedef void (*mid_callback_t)(struct TCP_Server_Info *srv, struct mid_q_entry *mid);

/*
 * This is the protopyte for mid handle function. This is called once the mid
 * has been recognized after decryption of the message.
 */
typedef int (*mid_handle_t)(struct TCP_Server_Info *server,
                            struct mid_q_entry *mid);

/* one of these for every pending CIFS request to the server */
struct mid_q_entry {
        struct list_head qhead; /* mids waiting on reply from this server */
        refcount_t refcount;
        __u64 mid;              /* multiplex id */
        __u16 credits;          /* number of credits consumed by this mid */
        __u16 credits_received; /* number of credits from the response */
        __u32 pid;              /* process id */
        __u32 sequence_number;  /* for CIFS signing */
        unsigned int sr_flags;  /* Flags passed to send_recv() */
        unsigned long when_alloc;  /* when mid was created */
#ifdef CONFIG_CIFS_STATS2
        unsigned long when_sent; /* time when smb send finished */
        unsigned long when_received; /* when demux complete (taken off wire) */
#endif
        mid_receive_t receive;  /* call receive callback */
        mid_callback_t callback; /* call completion callback */
        mid_handle_t handle;    /* call handle mid callback */
        void *callback_data;      /* general purpose pointer for callback */
        struct task_struct *creator;
        void *resp_buf;         /* pointer to received SMB header */
        unsigned int resp_buf_size;
        u32 response_pdu_len;
        int mid_state;  /* wish this were enum but can not pass to wait_event */
        int mid_rc;             /* rc for MID_RC */
        __le16 command;         /* smb command code */
        unsigned int optype;    /* operation type */
        spinlock_t mid_lock;
        bool wait_cancelled:1;  /* Cancelled while waiting for response */
        bool deleted_from_q:1;  /* Whether Mid has been dequeued frem pending_mid_q */
        bool large_buf:1;       /* if valid response, is pointer to large buf */
        bool multiRsp:1;        /* multiple trans2 responses for one request  */
        bool multiEnd:1;        /* both received */
        bool decrypted:1;       /* decrypted entry */
};

struct close_cancelled_open {
        struct cifs_fid         fid;
        struct cifs_tcon        *tcon;
        struct work_struct      work;
        __u64 mid;
        __u16 cmd;
};

/*      Make code in transport.c a little cleaner by moving
        update of optional stats into function below */
static inline void cifs_in_send_inc(struct TCP_Server_Info *server)
{
        atomic_inc(&server->in_send);
}

static inline void cifs_in_send_dec(struct TCP_Server_Info *server)
{
        atomic_dec(&server->in_send);
}

static inline void cifs_num_waiters_inc(struct TCP_Server_Info *server)
{
        atomic_inc(&server->num_waiters);
}

static inline void cifs_num_waiters_dec(struct TCP_Server_Info *server)
{
        atomic_dec(&server->num_waiters);
}

#ifdef CONFIG_CIFS_STATS2
static inline void cifs_save_when_sent(struct mid_q_entry *mid)
{
        mid->when_sent = jiffies;
}
#else
static inline void cifs_save_when_sent(struct mid_q_entry *mid)
{
}
#endif

/* for pending dnotify requests */
struct dir_notify_req {
        struct list_head lhead;
        __le16 Pid;
        __le16 PidHigh;
        __u16 Mid;
        __u16 Tid;
        __u16 Uid;
        __u16 netfid;
        __u32 filter; /* CompletionFilter (for multishot) */
        int multishot;
        struct file *pfile;
};

struct dfs_info3_param {
        int flags; /* DFSREF_REFERRAL_SERVER, DFSREF_STORAGE_SERVER*/
        int path_consumed;
        int server_type;
        int ref_flag;
        char *path_name;
        char *node_name;
        int ttl;
};

struct file_list {
        struct list_head list;
        struct cifsFileInfo *cfile;
};

struct cifs_mount_ctx {
        struct cifs_sb_info *cifs_sb;
        struct smb3_fs_context *fs_ctx;
        unsigned int xid;
        struct TCP_Server_Info *server;
        struct cifs_ses *ses;
        struct cifs_tcon *tcon;
};

struct mchan_mount {
        struct work_struct work;
        struct cifs_ses *ses;
};

static inline void __free_dfs_info_param(struct dfs_info3_param *param)
{
        kfree(param->path_name);
        kfree(param->node_name);
}

static inline void free_dfs_info_param(struct dfs_info3_param *param)
{
        if (param)
                __free_dfs_info_param(param);
}

static inline void zfree_dfs_info_param(struct dfs_info3_param *param)
{
        if (param) {
                __free_dfs_info_param(param);
                memset(param, 0, sizeof(*param));
        }
}

static inline void free_dfs_info_array(struct dfs_info3_param *param,
                                       int number_of_items)
{
        int i;

        if ((number_of_items == 0) || (param == NULL))
                return;
        for (i = 0; i < number_of_items; i++) {
                kfree(param[i].path_name);
                kfree(param[i].node_name);
        }
        kfree(param);
}

static inline bool is_interrupt_error(int error)
{
        switch (error) {
        case -EINTR:
        case -ERESTARTSYS:
        case -ERESTARTNOHAND:
        case -ERESTARTNOINTR:
                return true;
        }
        return false;
}

static inline bool is_retryable_error(int error)
{
        if (is_interrupt_error(error) || error == -EAGAIN)
                return true;
        return false;
}

static inline bool is_replayable_error(int error)
{
        if (error == -EAGAIN || error == -ECONNABORTED)
                return true;
        return false;
}


enum cifs_find_flags {
        FIND_ANY                = 0U,
        FIND_FSUID_ONLY         = (1U << 0),
        FIND_WITH_DELETE        = (1U << 1),
        FIND_NO_PENDING_DELETE  = (1U << 2),
        FIND_OPEN_FLAGS         = (1U << 3),
};

#define   MID_FREE 0
#define   MID_REQUEST_ALLOCATED 1
#define   MID_REQUEST_SUBMITTED 2
#define   MID_RESPONSE_RECEIVED 4
#define   MID_RETRY_NEEDED      8 /* session closed while this request out */
#define   MID_RESPONSE_MALFORMED 0x10
#define   MID_SHUTDOWN           0x20
#define   MID_RESPONSE_READY 0x40 /* ready for other process handle the rsp */
#define   MID_RC             0x80 /* mid_rc contains custom rc */

/* Types of response buffer returned from SendReceive2 */
#define   CIFS_NO_BUFFER        0    /* Response buffer not returned */
#define   CIFS_SMALL_BUFFER     1
#define   CIFS_LARGE_BUFFER     2
#define   CIFS_IOVEC            4    /* array of response buffers */

/* Type of Request to SendReceive2 */
#define   CIFS_BLOCKING_OP      1    /* operation can block */
#define   CIFS_NON_BLOCKING     2    /* do not block waiting for credits */
#define   CIFS_TIMEOUT_MASK 0x003    /* only one of above set in req */
#define   CIFS_LOG_ERROR    0x010    /* log NT STATUS if non-zero */
#define   CIFS_LARGE_BUF_OP 0x020    /* large request buffer */
#define   CIFS_NO_RSP_BUF   0x040    /* no response buffer required */

/* Type of request operation */
#define   CIFS_ECHO_OP            0x080  /* echo request */
#define   CIFS_OBREAK_OP          0x0100 /* oplock break request */
#define   CIFS_NEG_OP             0x0200 /* negotiate request */
#define   CIFS_CP_CREATE_CLOSE_OP 0x0400 /* compound create+close request */
/* Lower bitmask values are reserved by others below. */
#define   CIFS_SESS_OP            0x2000 /* session setup request */
#define   CIFS_OP_MASK            0x2780 /* mask request type */

#define   CIFS_HAS_CREDITS        0x0400 /* already has credits */
#define   CIFS_TRANSFORM_REQ      0x0800 /* transform request before sending */
#define   CIFS_NO_SRV_RSP         0x1000 /* there is no server response */
#define   CIFS_COMPRESS_REQ       0x4000 /* compress request before sending */
#define   CIFS_INTERRUPTIBLE_WAIT 0x8000 /* Interruptible wait (e.g. lock request) */
#define   CIFS_WINDOWS_LOCK       0x10000 /* We're trying to get a Windows lock */

/* Security Flags: indicate type of session setup needed */
#define   CIFSSEC_MAY_SIGN      0x00001
#define   CIFSSEC_MAY_NTLMV2    0x00004
#define   CIFSSEC_MAY_KRB5      0x00008
#define   CIFSSEC_MAY_SEAL      0x00040
#define   CIFSSEC_MAY_NTLMSSP   0x00080 /* raw ntlmssp with ntlmv2 */

#define   CIFSSEC_MUST_SIGN     0x01001
/* note that only one of the following can be set so the
result of setting MUST flags more than once will be to
require use of the stronger protocol */
#define   CIFSSEC_MUST_NTLMV2   0x04004
#define   CIFSSEC_MUST_KRB5     0x08008
#ifdef CONFIG_CIFS_UPCALL
#define   CIFSSEC_MASK          0xCF0CF /* flags supported if no weak allowed */
#else
#define   CIFSSEC_MASK          0xC70C7 /* flags supported if no weak allowed */
#endif /* UPCALL */
#define   CIFSSEC_MUST_SEAL     0x40040
#define   CIFSSEC_MUST_NTLMSSP  0x80080 /* raw ntlmssp with ntlmv2 */

#define   CIFSSEC_DEF (CIFSSEC_MAY_SIGN | CIFSSEC_MAY_NTLMV2 | CIFSSEC_MAY_NTLMSSP | CIFSSEC_MAY_SEAL)
#define   CIFSSEC_MAX (CIFSSEC_MAY_SIGN | CIFSSEC_MUST_KRB5 | CIFSSEC_MAY_SEAL)
#define   CIFSSEC_AUTH_MASK (CIFSSEC_MAY_NTLMV2 | CIFSSEC_MAY_KRB5 | CIFSSEC_MAY_NTLMSSP)
/*
 *****************************************************************
 * All constants go here
 *****************************************************************
 */

#define UID_HASH (16)

/*
 * Note that ONE module should define _DECLARE_GLOBALS_HERE to cause the
 * following to be declared.
 */

/****************************************************************************
 * LOCK ORDERING NOTES:
 ****************************************************************************
 * Here are all the locks (spinlock, mutex, semaphore) in cifs.ko, arranged according
 * to the locking order. i.e. if two locks are to be held together, the lock that
 * appears higher in this list needs to be taken before the other.
 *
 * If you hold a lock that is lower in this list, and you need to take a higher lock
 * (or if you think that one of the functions that you're calling may need to), first
 * drop the lock you hold, pick up the higher lock, then the lower one. This will
 * ensure that locks are picked up only in one direction in the below table
 * (top to bottom).
 *
 * Also, if you expect a function to be called with a lock held, explicitly document
 * this in the comments on top of your function definition.
 *
 * And also, try to keep the critical sections (lock hold time) to be as minimal as
 * possible. Blocking / calling other functions with a lock held always increase
 * the risk of a possible deadlock.
 *
 * Following this rule will avoid unnecessary deadlocks, which can get really hard to
 * debug. Also, any new lock that you introduce, please add to this list in the correct
 * order.
 *
 * Please populate this list whenever you introduce new locks in your changes. Or in
 * case I've missed some existing locks. Please ensure that it's added in the list
 * based on the locking order expected.
 *
 * =====================================================================================
 * Lock                         Protects                        Initialization fn
 * =====================================================================================
 * cifs_mount_mutex             mount/unmount operations
 * vol_list_lock
 * vol_info->ctx_lock           vol_info->ctx
 * cifs_sb_info->tlink_tree_lock        cifs_sb_info->tlink_tree        cifs_setup_cifs_sb
 * TCP_Server_Info->            TCP_Server_Info                 cifs_get_tcp_session
 * reconnect_mutex
 * cifs_ses->session_mutex      cifs_ses                        sesInfoAlloc
 * TCP_Server_Info->srv_mutex   TCP_Server_Info                 cifs_get_tcp_session
 * cifs_tcp_ses_lock            cifs_tcp_ses_list               sesInfoAlloc
 * cifs_tcon->open_file_lock    cifs_tcon->openFileList         tconInfoAlloc
 *                              cifs_tcon->pending_opens
 * cifs_tcon->stat_lock         cifs_tcon->bytes_read           tconInfoAlloc
 *                              cifs_tcon->bytes_written
 * cifs_tcon->fscache_lock      cifs_tcon->fscache              tconInfoAlloc
 * cifs_tcon->sb_list_lock      cifs_tcon->cifs_sb_list         tconInfoAlloc
 * GlobalMid_Lock               GlobalMaxActiveXid              init_cifs
 *                              GlobalCurrentXid
 *                              GlobalTotalActiveXid
 * TCP_Server_Info->srv_lock    (anything in struct not protected by another lock and can change)
 * TCP_Server_Info->mid_queue_lock      TCP_Server_Info->pending_mid_q  cifs_get_tcp_session
 *                              mid_q_entry->deleted_from_q
 * TCP_Server_Info->mid_counter_lock    TCP_Server_Info->current_mid    cifs_get_tcp_session
 * TCP_Server_Info->req_lock    TCP_Server_Info->in_flight      cifs_get_tcp_session
 *                              ->credits
 *                              ->echo_credits
 *                              ->oplock_credits
 *                              ->reconnect_instance
 * cifs_ses->ses_lock           (anything that is not protected by another lock and can change)
 *                                                              sesInfoAlloc
 * cifs_ses->iface_lock         cifs_ses->iface_list            sesInfoAlloc
 *                              ->iface_count
 *                              ->iface_last_update
 * cifs_ses->chan_lock          cifs_ses->chans                 sesInfoAlloc
 *                              ->chans_need_reconnect
 *                              ->chans_in_reconnect
 * cifs_tcon->tc_lock           (anything that is not protected by another lock and can change)
 *                                                              tcon_info_alloc
 * cifs_swnreg_idr_mutex        cifs_swnreg_idr                 cifs_swn.c
 *                              (witness service registration, accesses tcon fields under tc_lock)
 * inode->i_rwsem, taken by fs/netfs/locking.c e.g. should be taken before cifsInodeInfo locks
 * cifsInodeInfo->open_file_lock        cifsInodeInfo->openFileList     cifs_alloc_inode
 * cifsInodeInfo->writers_lock  cifsInodeInfo->writers          cifsInodeInfo_alloc
 * cifsInodeInfo->lock_sem      cifsInodeInfo->llist            cifs_init_once
 *                              ->can_cache_brlcks
 * cifsInodeInfo->deferred_lock cifsInodeInfo->deferred_closes  cifsInodeInfo_alloc
 * cached_fids->cfid_list_lock  cifs_tcon->cfids->entries       init_cached_dirs
 * cached_fid->dirents.de_mutex cached_fid->dirents             alloc_cached_dir
 * cifsFileInfo->fh_mutex       cifsFileInfo                    cifs_new_fileinfo
 * cifsFileInfo->file_info_lock cifsFileInfo->count             cifs_new_fileinfo
 *                              ->invalidHandle                 initiate_cifs_search
 *                              ->oplock_break_cancelled
 * smbdirect_mr->mutex          RDMA memory region management   (SMBDirect only)
 * mid_q_entry->mid_lock        mid_q_entry->callback           alloc_mid
 *                                                              smb2_mid_entry_alloc
 *                              (Any fields of mid_q_entry that will need protection)
 ****************************************************************************/

#ifdef DECLARE_GLOBALS_HERE
#define GLOBAL_EXTERN
#else
#define GLOBAL_EXTERN extern
#endif

/*
 * the list of TCP_Server_Info structures, ie each of the sockets
 * connecting our client to a distinct server (ip address), is
 * chained together by cifs_tcp_ses_list. The list of all our SMB
 * sessions (and from that the tree connections) can be found
 * by iterating over cifs_tcp_ses_list
 */
extern struct list_head         cifs_tcp_ses_list;

/*
 * This lock protects the cifs_tcp_ses_list, the list of smb sessions per
 * tcp session, and the list of tcon's per smb session. It also protects
 * the reference counters for the server, smb session, and tcon.
 * generally the locks should be taken in order tcp_ses_lock before
 * tcon->open_file_lock and that before file->file_info_lock since the
 * structure order is cifs_socket-->cifs_ses-->cifs_tcon-->cifs_file
 */
extern spinlock_t               cifs_tcp_ses_lock;

/*
 * Global transaction id (XID) information
 */
extern unsigned int GlobalCurrentXid;   /* protected by GlobalMid_Lock */
extern unsigned int GlobalTotalActiveXid; /* prot by GlobalMid_Lock */
extern unsigned int GlobalMaxActiveXid; /* prot by GlobalMid_Lock */
extern spinlock_t GlobalMid_Lock; /* protects above & list operations on midQ entries */

/*
 *  Global counters, updated atomically
 */
extern atomic_t sesInfoAllocCount;
extern atomic_t tconInfoAllocCount;
extern atomic_t tcpSesNextId;
extern atomic_t tcpSesAllocCount;
extern atomic_t tcpSesReconnectCount;
extern atomic_t tconInfoReconnectCount;

/* Various Debug counters */
extern atomic_t buf_alloc_count;        /* current number allocated  */
extern atomic_t small_buf_alloc_count;
#ifdef CONFIG_CIFS_STATS2
extern atomic_t total_buf_alloc_count; /* total allocated over all time */
extern atomic_t total_small_buf_alloc_count;
extern unsigned int slow_rsp_threshold; /* number of secs before logging */
#endif

/* Misc globals */
extern bool enable_oplocks; /* enable or disable oplocks */
extern bool lookupCacheEnabled;
extern unsigned int global_secflags;    /* if on, session setup sent
                                with more secure ntlmssp2 challenge/resp */
extern unsigned int sign_CIFS_PDUs;  /* enable smb packet signing */
extern bool enable_gcm_256; /* allow optional negotiate of strongest signing (aes-gcm-256) */
extern bool require_gcm_256; /* require use of strongest signing (aes-gcm-256) */
extern bool enable_negotiate_signing; /* request use of faster (GMAC) signing if available */
extern bool linuxExtEnabled;/*enable Linux/Unix CIFS extensions*/
extern unsigned int CIFSMaxBufSize;  /* max size not including hdr */
extern unsigned int cifs_min_rcv;    /* min size of big ntwrk buf pool */
extern unsigned int cifs_min_small;  /* min size of small buf pool */
extern unsigned int cifs_max_pending; /* MAX requests at once to server*/
extern unsigned int dir_cache_timeout; /* max time for directory lease caching of dir */
extern bool disable_legacy_dialects;  /* forbid vers=1.0 and vers=2.0 mounts */
extern atomic_t mid_count;

void cifs_oplock_break(struct work_struct *work);
void cifs_queue_oplock_break(struct cifsFileInfo *cfile);
void smb2_deferred_work_close(struct work_struct *work);

extern const struct slow_work_ops cifs_oplock_break_ops;
extern struct workqueue_struct *cifsiod_wq;
extern struct workqueue_struct *decrypt_wq;
extern struct workqueue_struct *fileinfo_put_wq;
extern struct workqueue_struct *cifsoplockd_wq;
extern struct workqueue_struct *deferredclose_wq;
extern struct workqueue_struct *serverclose_wq;
extern struct workqueue_struct *cfid_put_wq;
extern __u32 cifs_lock_secret;

extern mempool_t *cifs_sm_req_poolp;
extern mempool_t *cifs_req_poolp;
extern mempool_t cifs_mid_pool;
extern mempool_t cifs_io_request_pool;
extern mempool_t cifs_io_subrequest_pool;

/* Operations for different SMB versions */
#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
extern struct smb_version_operations smb20_operations;
extern struct smb_version_values smb20_values;
#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
extern struct smb_version_operations smb21_operations;
extern struct smb_version_values smb21_values;
extern struct smb_version_values smbdefault_values;
extern struct smb_version_values smb3any_values;
extern struct smb_version_operations smb30_operations;
extern struct smb_version_values smb30_values;
/*extern struct smb_version_operations smb302_operations;*/ /* not needed yet */
extern struct smb_version_values smb302_values;
extern struct smb_version_operations smb311_operations;
extern struct smb_version_values smb311_values;

static inline char *get_security_type_str(enum securityEnum sectype)
{
        switch (sectype) {
        case RawNTLMSSP:
                return "RawNTLMSSP";
        case Kerberos:
                return "Kerberos";
        case NTLMv2:
                return "NTLMv2";
        case IAKerb:
                return "IAKerb";
        default:
                return "Unknown";
        }
}

static inline bool is_smb1_server(struct TCP_Server_Info *server)
{
        return strcmp(server->vals->version_string, SMB1_VERSION_STRING) == 0;
}

static inline bool is_tcon_dfs(struct cifs_tcon *tcon)
{
        /*
         * For SMB1, see MS-CIFS 2.4.55 SMB_COM_TREE_CONNECT_ANDX (0x75) and MS-CIFS 3.3.4.4 DFS
         * Subsystem Notifies That a Share Is a DFS Share.
         *
         * For SMB2+, see MS-SMB2 2.2.10 SMB2 TREE_CONNECT Response and MS-SMB2 3.3.4.14 Server
         * Application Updates a Share.
         */
        if (!tcon || !tcon->ses || !tcon->ses->server)
                return false;
        return is_smb1_server(tcon->ses->server) ? tcon->Flags & SMB_SHARE_IS_IN_DFS :
                tcon->share_flags & (SHI1005_FLAGS_DFS | SHI1005_FLAGS_DFS_ROOT);
}

static inline bool cifs_is_referral_server(struct cifs_tcon *tcon,
                                           const struct dfs_info3_param *ref)
{
        /*
         * Check if all targets are capable of handling DFS referrals as per
         * MS-DFSC 2.2.4 RESP_GET_DFS_REFERRAL.
         */
        return is_tcon_dfs(tcon) || (ref && (ref->flags & DFSREF_REFERRAL_SERVER));
}

static inline u64 cifs_flock_len(const struct file_lock *fl)
{
        return (u64)fl->fl_end - fl->fl_start + 1;
}

static inline size_t ntlmssp_workstation_name_size(const struct cifs_ses *ses)
{
        if (WARN_ON_ONCE(!ses || !ses->server))
                return 0;
        /*
         * Make workstation name no more than 15 chars when using insecure dialects as some legacy
         * servers do require it during NTLMSSP.
         */
        if (ses->server->dialect <= SMB20_PROT_ID)
                return min_t(size_t, sizeof(ses->workstation_name), RFC1001_NAME_LEN_WITH_NULL);
        return sizeof(ses->workstation_name);
}

static inline void move_cifs_info_to_smb2(struct smb2_file_all_info *dst, const FILE_ALL_INFO *src)
{
        memcpy(dst, src, (size_t)((u8 *)&src->EASize - (u8 *)src));
        dst->IndexNumber = 0;
        dst->EASize = src->EASize;
        dst->AccessFlags = 0;
        dst->CurrentByteOffset = 0;
        dst->Mode = 0;
        dst->AlignmentRequirement = 0;
        dst->FileNameLength = src->FileNameLength;
}

#define CIFS_OPARMS(_cifs_sb, _tcon, _path, _da, _cd, _co, _mode) \
        ((struct cifs_open_parms) { \
                .tcon = _tcon, \
                .path = _path, \
                .desired_access = (_da), \
                .disposition = (_cd), \
                .create_options = cifs_create_options(_cifs_sb, (_co)), \
                .mode = (_mode), \
                .cifs_sb = _cifs_sb, \
        })

struct smb2_compound_vars {
        struct cifs_open_parms oparms;
        struct kvec rsp_iov[MAX_COMPOUND];
        struct smb_rqst rqst[MAX_COMPOUND];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec qi_iov;
        struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
        struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
        struct kvec unlink_iov[SMB2_SET_INFO_IOV_SIZE];
        struct kvec rename_iov[SMB2_SET_INFO_IOV_SIZE];
        struct kvec close_iov;
        struct smb2_file_rename_info_hdr rename_info;
        struct smb2_file_link_info_hdr link_info;
        struct kvec ea_iov;
};

static inline bool cifs_ses_exiting(struct cifs_ses *ses)
{
        bool ret;

        spin_lock(&ses->ses_lock);
        ret = ses->ses_status == SES_EXITING;
        spin_unlock(&ses->ses_lock);
        return ret;
}

static inline bool cifs_netbios_name(const char *name, size_t namelen)
{
        bool ret = false;
        size_t i;

        if (namelen >= 1 && namelen <= RFC1001_NAME_LEN) {
                for (i = 0; i < namelen; i++) {
                        const unsigned char c = name[i];

                        if (c == '\\' || c == '/' || c == ':' || c == '*' ||
                            c == '?' || c == '"' || c == '<' || c == '>' ||
                            c == '|' || c == '.')
                                return false;
                        if (!ret && isalpha(c))
                                ret = true;
                }
        }
        return ret;
}

/*
 * Execute mid callback atomically - ensures callback runs exactly once
 * and prevents sleeping in atomic context.
 */
static inline void mid_execute_callback(struct TCP_Server_Info *server,
                                        struct mid_q_entry *mid)
{
        mid_callback_t callback;

        spin_lock(&mid->mid_lock);
        callback = mid->callback;
        mid->callback = NULL;  /* Mark as executed, */
        spin_unlock(&mid->mid_lock);

        if (callback)
                callback(server, mid);
}

#define CIFS_REPARSE_SUPPORT(tcon) \
        ((tcon)->posix_extensions || \
         (le32_to_cpu((tcon)->fsAttrInfo.Attributes) & \
          FILE_SUPPORTS_REPARSE_POINTS))

struct cifs_calc_sig_ctx {
        struct md5_ctx *md5;
        struct hmac_sha256_ctx *hmac;
        struct shash_desc *shash;
};

#define CIFS_RECONN_DELAY_SECS  30
#define CIFS_MAX_RECONN_DELAY   (4 * CIFS_RECONN_DELAY_SECS)

static inline void cifs_queue_server_reconn(struct TCP_Server_Info *server)
{
        if (!delayed_work_pending(&server->reconnect)) {
                WRITE_ONCE(server->reconn_delay, 0);
                mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
        }
}

static inline void cifs_requeue_server_reconn(struct TCP_Server_Info *server)
{
        unsigned long delay = READ_ONCE(server->reconn_delay);

        delay = umin(delay + CIFS_RECONN_DELAY_SECS, CIFS_MAX_RECONN_DELAY);
        WRITE_ONCE(server->reconn_delay, delay);
        queue_delayed_work(cifsiod_wq, &server->reconnect, delay * HZ);
}

static inline bool __cifs_cache_state_check(struct cifsInodeInfo *cinode,
                                            unsigned int oplock_flags,
                                            unsigned int sb_flags)
{
        unsigned int sflags = cifs_sb_flags(CIFS_SB(cinode));
        unsigned int oplock = READ_ONCE(cinode->oplock);

        return (oplock & oplock_flags) || (sflags & sb_flags);
}

#define CIFS_CACHE_READ(cinode) \
        __cifs_cache_state_check(cinode, CIFS_CACHE_READ_FLG, \
                                 CIFS_MOUNT_RO_CACHE)
#define CIFS_CACHE_HANDLE(cinode) \
        __cifs_cache_state_check(cinode, CIFS_CACHE_HANDLE_FLG, 0)
#define CIFS_CACHE_WRITE(cinode) \
        __cifs_cache_state_check(cinode, CIFS_CACHE_WRITE_FLG, \
                                 CIFS_MOUNT_RW_CACHE)

static inline void cifs_reset_oplock(struct cifsInodeInfo *cinode)
{
        scoped_guard(spinlock, &cinode->open_file_lock)
                WRITE_ONCE(cinode->oplock, 0);
}

static inline bool cifs_forced_shutdown(const struct cifs_sb_info *sbi)
{
        return cifs_sb_flags(sbi) & CIFS_MOUNT_SHUTDOWN;
}

static inline int cifs_open_create_options(unsigned int oflags, int opts)
{
        /* O_SYNC also has bit for O_DSYNC so following check picks up either */
        if (oflags & O_SYNC)
                opts |= CREATE_WRITE_THROUGH;
        if (oflags & O_DIRECT)
                opts |= CREATE_NO_BUFFER;
        return opts;
}

/*
 * The number of blocks is not related to (i_size / i_blksize), but instead
 * 512 byte (2**9) size is required for calculating num blocks.
 */
#define CIFS_INO_BLOCKS(size) DIV_ROUND_UP_ULL((u64)(size), 512)

#endif  /* _CIFS_GLOB_H */