Merge remote-tracking branch 'media_tree/vsp1' into generic-zpos-v8

[deliverable/linux.git] / fs / cifs / cifsglob.h

/*
 *   fs/cifs/cifsglob.h
 *
 *   Copyright (C) International Business Machines  Corp., 2002,2008
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *              Jeremy Allison (jra@samba.org)
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 */
#ifndef _CIFS_GLOB_H
#define _CIFS_GLOB_H

#include <linux/in.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <linux/mempool.h>
#include <linux/workqueue.h>
#include "cifs_fs_sb.h"
#include "cifsacl.h"
#include <crypto/internal/hash.h>
#include <linux/scatterlist.h>
#include <uapi/linux/cifs/cifs_mount.h>
#ifdef CONFIG_CIFS_SMB2
#include "smb2pdu.h"
#endif

#define CIFS_MAGIC_NUMBER 0xFF534D42      /* the first four bytes of SMB PDUs */

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

/*
 * 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)

/* currently length of NIP6_FMT */
#define SERVER_NAME_LENGTH 40
#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

#include "cifspdu.h"

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

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

/* associated with each tcp and smb session */
enum statusEnum {
        CifsNew = 0,
        CifsGood,
        CifsExiting,
        CifsNeedReconnect,
        CifsNeedNegotiate
};

enum securityEnum {
        Unspecified = 0,        /* not specified */
        LANMAN,                 /* Legacy LANMAN auth */
        NTLM,                   /* Legacy NTLM012 auth with NTLM hash */
        NTLMv2,                 /* Legacy NTLM auth with NTLMv2 hash */
        RawNTLMSSP,             /* NTLMSSP without SPNEGO, NTLMv2 hash */
        Kerberos,               /* Kerberos via SPNEGO */
};

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

/* crypto security descriptor definition */
struct sdesc {
        struct shash_desc shash;
        char ctx[];
};

/* crypto hashing related structure/fields, not specific to a sec mech */
struct cifs_secmech {
        struct crypto_shash *hmacmd5; /* hmac-md5 hash function */
        struct crypto_shash *md5; /* md5 hash function */
        struct crypto_shash *hmacsha256; /* hmac-sha256 hash function */
        struct crypto_shash *cmacaes; /* block-cipher based MAC function */
        struct sdesc *sdeschmacmd5;  /* ctxt to generate ntlmv2 hash, CR1 */
        struct sdesc *sdescmd5; /* ctxt to generate cifs/smb signature */
        struct sdesc *sdeschmacsha256;  /* ctxt to generate smb2 signature */
        struct sdesc *sdesccmacaes;  /* ctxt to generate smb3 signature */
};

/* 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 cifs_sid osid;
        struct cifs_sid gsid;
        struct cifs_ntace *ntaces;
        struct cifs_ace *aces;
};

/*
 *****************************************************************
 * 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 page     **rq_pages;     /* pointer to array of page ptrs */
        unsigned int    rq_npages;      /* number pages in array */
        unsigned int    rq_pagesz;      /* page size to use */
        unsigned int    rq_tailsz;      /* length of last page */
};

enum smb_version {
        Smb_1 = 1,
        Smb_20,
        Smb_21,
        Smb_30,
        Smb_302,
#ifdef CONFIG_CIFS_SMB311
        Smb_311,
#endif /* SMB311 */
        Smb_version_err
};

struct mid_q_entry;
struct TCP_Server_Info;
struct cifsFileInfo;
struct cifs_ses;
struct cifs_tcon;
struct dfs_info3_param;
struct cifs_fattr;
struct smb_vol;
struct cifs_fid;
struct cifs_readdata;
struct cifs_writedata;
struct cifs_io_parms;
struct cifs_search_info;
struct cifsInodeInfo;
struct cifs_open_parms;

struct smb_version_operations {
        int (*send_cancel)(struct TCP_Server_Info *, void *,
                           struct mid_q_entry *);
        bool (*compare_fids)(struct cifsFileInfo *, struct cifsFileInfo *);
        /* setup request: allocate mid, sign message */
        struct mid_q_entry *(*setup_request)(struct cifs_ses *,
                                                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 *, const unsigned int,
                            const int);
        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 *);
        /* data offset from read response message */
        unsigned int (*read_data_offset)(char *);
        /* data length from read response message */
        unsigned int (*read_data_length)(char *);
        /* 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 *, char *);
        void (*dump_detail)(void *);
        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 *, unsigned int, struct TCP_Server_Info *);
        bool (*is_oplock_break)(char *, struct TCP_Server_Info *);
        void (*downgrade_oplock)(struct TCP_Server_Info *,
                                        struct cifsInodeInfo *, bool);
        /* 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, struct cifs_ses *);
        /* set negotiated write size */
        unsigned int (*negotiate_wsize)(struct cifs_tcon *, struct smb_vol *);
        /* set negotiated read size */
        unsigned int (*negotiate_rsize)(struct cifs_tcon *, struct smb_vol *);
        /* setup smb sessionn */
        int (*sess_setup)(const unsigned int, struct cifs_ses *,
                          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 connecion */
        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 *);
        /* 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, struct cifs_tcon *,
                               struct cifs_sb_info *, const char *,
                               FILE_ALL_INFO *, bool *, bool *);
        /* query file data from the server */
        int (*query_file_info)(const unsigned int, struct cifs_tcon *,
                               struct cifs_fid *, FILE_ALL_INFO *);
        /* get server index number */
        int (*get_srv_inum)(const unsigned int, struct cifs_tcon *,
                            struct cifs_sb_info *, const char *,
                            u64 *uniqueid, FILE_ALL_INFO *);
        /* set size by path */
        int (*set_path_size)(const unsigned int, struct cifs_tcon *,
                             const char *, __u64, struct cifs_sb_info *, bool);
        /* 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 (*mkdir)(const unsigned int, struct cifs_tcon *, const char *,
                     struct cifs_sb_info *);
        /* 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 *);
        /* open, rename and delete file */
        int (*rename_pending_delete)(const char *, struct dentry *,
                                     const unsigned int);
        /* send rename request */
        int (*rename)(const unsigned int, struct cifs_tcon *, const char *,
                      const char *, struct cifs_sb_info *);
        /* send create hardlink request */
        int (*create_hardlink)(const unsigned int, struct cifs_tcon *,
                               const char *, const char *,
                               struct cifs_sb_info *);
        /* query symlink target */
        int (*query_symlink)(const unsigned int, struct cifs_tcon *,
                             const char *, char **, struct cifs_sb_info *);
        /* open a file for non-posix mounts */
        int (*open)(const unsigned int, struct cifs_open_parms *,
                    __u32 *, FILE_ALL_INFO *);
        /* set fid protocol-specific info */
        void (*set_fid)(struct cifsFileInfo *, struct cifs_fid *, __u32);
        /* close a file */
        void (*close)(const unsigned int, struct cifs_tcon *,
                      struct cifs_fid *);
        /* 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_readdata *);
        /* async write to the server */
        int (*async_writev)(struct cifs_writedata *,
                            void (*release)(struct kref *));
        /* 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 *);
        /* check for STATUS_PENDING and process it in a positive case */
        bool (*is_status_pending)(char *, struct TCP_Server_Info *, int);
        /* send oplock break response */
        int (*oplock_response)(struct cifs_tcon *, struct cifs_fid *,
                               struct cifsInodeInfo *);
        /* query remote filesystem */
        int (*queryfs)(const unsigned int, struct cifs_tcon *,
                       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 *);
        int (*calc_signature)(struct smb_rqst *, struct TCP_Server_Info *);
        int (*set_integrity)(const unsigned int, struct cifs_tcon *tcon,
                             struct cifsFileInfo *src_file);
        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 *, __u32, unsigned int,
                                 bool *);
        /* create lease context buffer for CREATE request */
        char * (*create_lease_buf)(u8 *, u8);
        /* parse lease context buffer and return oplock/epoch info */
        __u8 (*parse_lease_buf)(void *, unsigned int *);
        int (*clone_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, const struct nls_table *, int);
        int (*set_EA)(const unsigned int, struct cifs_tcon *, const char *,
                        const char *, const void *, const __u16,
                        const struct nls_table *, int);
        struct cifs_ntsd * (*get_acl)(struct cifs_sb_info *, struct inode *,
                        const char *, u32 *);
        struct cifs_ntsd * (*get_acl_by_fid)(struct cifs_sb_info *,
                        const struct cifs_fid *, u32 *);
        int (*set_acl)(struct cifs_ntsd *, __u32, struct inode *, const char *,
                        int);
        /* writepages retry size */
        unsigned int (*wp_retry_size)(struct inode *);
        /* get mtu credits */
        int (*wait_mtu_credits)(struct TCP_Server_Info *, unsigned int,
                                unsigned int *, unsigned int *);
        /* 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);
};

struct smb_version_values {
        char            *version_string;
        __u16           protocol_id;
        __u32           req_capabilities;
        __u32           large_lock_type;
        __u32           exclusive_lock_type;
        __u32           shared_lock_type;
        __u32           unlock_lock_type;
        size_t          header_size;
        size_t          max_header_size;
        size_t          read_rsp_size;
        __le16          lock_cmd;
        unsigned int    cap_unix;
        unsigned int    cap_nt_find;
        unsigned int    cap_large_files;
        __u16           signing_enabled;
        __u16           signing_required;
        size_t          create_lease_size;
};

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

struct smb_vol {
        char *username;
        char *password;
        char *domainname;
        char *UNC;
        char *iocharset;  /* local code page for mapping to and from Unicode */
        char source_rfc1001_name[RFC1001_NAME_LEN_WITH_NULL]; /* clnt nb name */
        char target_rfc1001_name[RFC1001_NAME_LEN_WITH_NULL]; /* srvr nb name */
        kuid_t cred_uid;
        kuid_t linux_uid;
        kgid_t linux_gid;
        kuid_t backupuid;
        kgid_t backupgid;
        umode_t file_mode;
        umode_t dir_mode;
        enum securityEnum sectype; /* sectype requested via mnt opts */
        bool sign; /* was signing requested via mnt opts? */
        bool retry:1;
        bool intr:1;
        bool setuids:1;
        bool override_uid:1;
        bool override_gid:1;
        bool dynperm:1;
        bool noperm:1;
        bool no_psx_acl:1; /* set if posix acl support should be disabled */
        bool cifs_acl:1;
        bool backupuid_specified; /* mount option  backupuid  is specified */
        bool backupgid_specified; /* mount option  backupgid  is specified */
        bool no_xattr:1;   /* set if xattr (EA) support should be disabled*/
        bool server_ino:1; /* use inode numbers from server ie UniqueId */
        bool direct_io:1;
        bool strict_io:1; /* strict cache behavior */
        bool remap:1;      /* set to remap seven reserved chars in filenames */
        bool sfu_remap:1;  /* remap seven reserved chars ala SFU */
        bool posix_paths:1; /* unset to not ask for posix pathnames. */
        bool no_linux_ext:1;
        bool sfu_emul:1;
        bool nullauth:1;   /* attempt to authenticate with null user */
        bool nocase:1;     /* request case insensitive filenames */
        bool nobrl:1;      /* disable sending byte range locks to srv */
        bool mand_lock:1;  /* send mandatory not posix byte range lock reqs */
        bool seal:1;       /* request transport encryption on share */
        bool nodfs:1;      /* Do not request DFS, even if available */
        bool local_lease:1; /* check leases only on local system, not remote */
        bool noblocksnd:1;
        bool noautotune:1;
        bool nostrictsync:1; /* do not force expensive SMBflush on every sync */
        bool fsc:1;     /* enable fscache */
        bool mfsymlinks:1; /* use Minshall+French Symlinks */
        bool multiuser:1;
        bool rwpidforward:1; /* pid forward for read/write operations */
        bool nosharesock:1;
        bool persistent:1;
        bool nopersistent:1;
        bool resilient:1; /* noresilient not required since not fored for CA */
        unsigned int rsize;
        unsigned int wsize;
        bool sockopt_tcp_nodelay:1;
        unsigned long actimeo; /* attribute cache timeout (jiffies) */
        struct smb_version_operations *ops;
        struct smb_version_values *vals;
        char *prepath;
        struct sockaddr_storage dstaddr; /* destination address */
        struct sockaddr_storage srcaddr; /* allow binding to a local IP */
        struct nls_table *local_nls;
        unsigned int echo_interval; /* echo interval in secs */
};

#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)

#define CIFS_MS_MASK (MS_RDONLY | MS_MANDLOCK | MS_NOEXEC | MS_NOSUID | \
                      MS_NODEV | MS_SYNCHRONOUS)

struct cifs_mnt_data {
        struct cifs_sb_info *cifs_sb;
        struct smb_vol *vol;
        int flags;
};

static inline unsigned int
get_rfc1002_length(void *buf)
{
        return be32_to_cpu(*((__be32 *)buf)) & 0xffffff;
}

static inline void
inc_rfc1001_len(void *buf, int count)
{
        be32_add_cpu((__be32 *)buf, count);
}

struct TCP_Server_Info {
        struct list_head tcp_ses_list;
        struct list_head smb_ses_list;
        int srv_count; /* reference counter */
        /* 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;
        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*/
        struct list_head pending_mid_q;
        bool noblocksnd;                /* use blocking sendmsg */
        bool noautotune;                /* do not autotune send buf sizes */
        bool tcp_nodelay;
        int credits;  /* send no more requests at once */
        unsigned int in_flight;  /* number of requests on the wire to server */
        spinlock_t req_lock;  /* protect the two values above */
        struct mutex srv_mutex;
        struct task_struct *tsk;
        char server_GUID[16];
        __u16 sec_mode;
        bool sign; /* is signing enabled on this connection? */
        bool session_estab; /* mark when very first sess is established */
#ifdef CONFIG_CIFS_SMB2
        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 */
#endif
        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 */
        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 CurrentMid;         /* multiplex id - rotating counter */
        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 */
        struct session_key session_key;
        unsigned long lstrp; /* when we got last response from this server */
        struct cifs_secmech secmech; /* crypto sec mech functs, descriptors */
#define CIFS_NEGFLAVOR_LANMAN   0       /* wct == 13, LANMAN */
#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    large_buf;              /* is current buffer large? */
        struct delayed_work     echo; /* echo ping workqueue job */
        char    *smallbuf;      /* pointer to current "small" buffer */
        char    *bigbuf;        /* pointer to current "big" buffer */
        unsigned int total_read; /* total amount of data read in this pass */
#ifdef CONFIG_CIFS_FSCACHE
        struct fscache_cookie   *fscache; /* client index cache cookie */
#endif
#ifdef CONFIG_CIFS_STATS2
        atomic_t in_send; /* requests trying to send */
        atomic_t num_waiters;   /* blocked waiting to get in sendrecv */
#endif
#ifdef CONFIG_CIFS_SMB2
        unsigned int    max_read;
        unsigned int    max_write;
        __u8            preauth_hash[512];
#endif /* CONFIG_CIFS_SMB2 */
        unsigned long echo_interval;
};

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;
        spin_lock(&server->req_lock);
        num = *credits;
        spin_unlock(&server->req_lock);
        return num > 0;
}

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

static inline void
add_credits_and_wake_if(struct TCP_Server_Info *server, const unsigned int add,
                        const int optype)
{
        if (add) {
                server->ops->add_credits(server, add, optype);
                wake_up(&server->request_q);
        }
}

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

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 __u16
get_mid(const struct smb_hdr *smb)
{
        return le16_to_cpu(smb->Mid);
}

static inline bool
compare_mid(__u16 mid, const struct smb_hdr *smb)
{
        return mid == le16_to_cpu(smb->Mid);
}

/*
 * 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) + 4)
#define CIFS_MAX_RSIZE ((1<<24) - sizeof(READ_RSP) + 4)

/*
 * 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) + 4)
#define CIFS_MAX_RFC1002_RSIZE ((1<<17) - 1 - sizeof(READ_RSP) + 4)

/*
 * The default wsize is 1M. find_get_pages seems to return a maximum of 256
 * pages in a single call. With PAGE_SIZE == 4k, this means we can fill
 * a single wsize request with a single call.
 */
#define CIFS_DEFAULT_IOSIZE (1024 * 1024)

/*
 * 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:
 *
 * http://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

/*
 * 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 tcon_list;
        struct mutex session_mutex;
        struct TCP_Server_Info *server; /* pointer to server info */
        int ses_count;          /* reference counter */
        enum statusEnum status;
        unsigned overrideSecFlg;  /* if non-zero override global sec flags */
        __u16 ipc_tid;          /* special tid for connection to IPC share */
        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 serverName[SERVER_NAME_LEN_WITH_NULL * 2]; /* BB make bigger for
                                TCP names - will ipv6 and sctp addresses fit? */
        char *user_name;        /* must not be null except during init of sess
                                   and after mount option parsing we fill it */
        char *domainName;
        char *password;
        struct session_key auth_key;
        struct ntlmssp_auth *ntlmssp; /* ciphertext, flags, server challenge */
        enum securityEnum sectype; /* what security flavor was specified? */
        bool sign;              /* is signing required? */
        bool need_reconnect:1; /* connection reset, uid now invalid */
#ifdef CONFIG_CIFS_SMB2
        __u16 session_flags;
        __u8 smb3signingkey[SMB3_SIGN_KEY_SIZE];
        __u8 smb3encryptionkey[SMB3_SIGN_KEY_SIZE];
        __u8 smb3decryptionkey[SMB3_SIGN_KEY_SIZE];
        __u8 preauth_hash[512];
#endif /* CONFIG_CIFS_SMB2 */
};

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

/*
 * there is one of these for each connection to a resource on a particular
 * session
 */
struct cifs_tcon {
        struct list_head tcon_list;
        int tc_count;
        struct list_head openFileList;
        struct cifs_ses *ses;   /* pointer to session associated with */
        char treeName[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 statusEnum tidStatus;
#ifdef CONFIG_CIFS_STATS
        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;
#ifdef CONFIG_CIFS_SMB2
                struct {
                        atomic_t smb2_com_sent[NUMBER_OF_SMB2_COMMANDS];
                        atomic_t smb2_com_failed[NUMBER_OF_SMB2_COMMANDS];
                } smb2_stats;
#endif /* CONFIG_CIFS_SMB2 */
        } stats;
#ifdef CONFIG_CIFS_STATS2
        unsigned long long time_writes;
        unsigned long long time_reads;
        unsigned long long time_opens;
        unsigned long long time_deletes;
        unsigned long long time_closes;
        unsigned long long time_mkdirs;
        unsigned long long time_rmdirs;
        unsigned long long time_renames;
        unsigned long long time_t2renames;
        unsigned long long time_ffirst;
        unsigned long long time_fnext;
        unsigned long long time_fclose;
#endif /* CONFIG_CIFS_STATS2 */
        __u64    bytes_read;
        __u64    bytes_written;
        spinlock_t stat_lock;
#endif /* CONFIG_CIFS_STATS */
        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$ eg for RPC/PIPES */
        bool retry:1;
        bool nocase: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 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 use_resilient:1; /* use resilient instead of durable handles */
        bool use_persistent:1; /* use persistent instead of durable handles */
#ifdef CONFIG_CIFS_SMB2
        bool print:1;           /* set if connection to printer share */
        bool bad_network_name:1; /* set if ret status STATUS_BAD_NETWORK_NAME */
        __le32 capabilities;
        __u32 share_flags;
        __u32 maximal_access;
        __u32 vol_serial_number;
        __le64 vol_create_time;
        __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;
#endif /* CONFIG_CIFS_SMB2 */
#ifdef CONFIG_CIFS_FSCACHE
        u64 resource_id;                /* server resource id */
        struct fscache_cookie *fscache; /* cookie for share */
#endif
        struct list_head pending_opens; /* list of incomplete opens */
        /* BB add field for back pointer to sb struct(s)? */
};

/*
 * 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;
};

extern struct tcon_link *cifs_sb_tlink(struct cifs_sb_info *cifs_sb);

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

extern 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 */
extern 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;
};

/*
 * 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;
        __u32 type;
};

/*
 * 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 */
};

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;
        bool reconnect:1;
};

struct cifs_fid {
        __u16 netfid;
#ifdef CONFIG_CIFS_SMB2
        __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 create_guid[16];
#endif
        struct cifs_pending_open *pending_open;
        unsigned int epoch;
        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 {
        struct list_head tlist; /* pointer to next fid owned by tcon */
        struct list_head flist; /* next fid (file instance) for this inode */
        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 */
        /* BB add lock scope info here if needed */ ;
        /* lock scope id (0 if none) */
        struct dentry *dentry;
        unsigned int f_flags;
        struct tcon_link *tlink;
        bool invalidHandle:1;   /* file closed via session abend */
        bool oplock_break_cancelled:1;
        int count;              /* refcount protected by cifs_file_list_lock */
        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 cifs_io_parms {
        __u16 netfid;
#ifdef CONFIG_CIFS_SMB2
        __u64 persistent_fid;   /* persist file id for smb2 */
        __u64 volatile_fid;     /* volatile file id for smb2 */
#endif
        __u32 pid;
        __u64 offset;
        unsigned int length;
        struct cifs_tcon *tcon;
};

struct cifs_readdata;

/* asynchronous read support */
struct cifs_readdata {
        struct kref                     refcount;
        struct list_head                list;
        struct completion               done;
        struct cifsFileInfo             *cfile;
        struct address_space            *mapping;
        __u64                           offset;
        unsigned int                    bytes;
        unsigned int                    got_bytes;
        pid_t                           pid;
        int                             result;
        struct work_struct              work;
        int (*read_into_pages)(struct TCP_Server_Info *server,
                                struct cifs_readdata *rdata,
                                unsigned int len);
        struct kvec                     iov;
        unsigned int                    pagesz;
        unsigned int                    tailsz;
        unsigned int                    credits;
        unsigned int                    nr_pages;
        struct page                     *pages[];
};

struct cifs_writedata;

/* asynchronous write support */
struct cifs_writedata {
        struct kref                     refcount;
        struct list_head                list;
        struct completion               done;
        enum writeback_sync_modes       sync_mode;
        struct work_struct              work;
        struct cifsFileInfo             *cfile;
        __u64                           offset;
        pid_t                           pid;
        unsigned int                    bytes;
        int                             result;
        unsigned int                    pagesz;
        unsigned int                    tailsz;
        unsigned int                    credits;
        unsigned int                    nr_pages;
        struct page                     *pages[];
};

/*
 * Take a reference on the file private data. Must be called with
 * cifs_file_list_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);

#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)

#define CIFS_CACHE_READ(cinode) (cinode->oplock & CIFS_CACHE_READ_FLG)
#define CIFS_CACHE_HANDLE(cinode) (cinode->oplock & CIFS_CACHE_HANDLE_FLG)
#define CIFS_CACHE_WRITE(cinode) (cinode->oplock & CIFS_CACHE_WRITE_FLG)

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

struct cifsInodeInfo {
        bool can_cache_brlcks;
        struct list_head llist; /* locks helb by this inode */
        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;
        __u32 cifsAttrs; /* e.g. DOS archive bit, sparse, compressed, system */
        unsigned int oplock;            /* oplock/lease level we have */
        unsigned int 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_DOWNGRADE_OPLOCK_TO_L2 (2) /* Downgrade oplock to L2 */
#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 */
        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  server_eof;                /* current file size on server -- protected by i_lock */
        u64  uniqueid;                  /* server inode number */
        u64  createtime;                /* creation time on server */
#ifdef CONFIG_CIFS_SMB2
        __u8 lease_key[SMB2_LEASE_KEY_SIZE];    /* lease key for this inode */
#endif
#ifdef CONFIG_CIFS_FSCACHE
        struct fscache_cookie *fscache;
#endif
        struct inode vfs_inode;
};

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

static inline struct cifs_sb_info *
CIFS_SB(struct super_block *sb)
{
        return sb->s_fs_info;
}

static inline struct cifs_sb_info *
CIFS_FILE_SB(struct file *file)
{
        return CIFS_SB(file_inode(file)->i_sb);
}

static inline char CIFS_DIR_SEP(const struct cifs_sb_info *cifs_sb)
{
        if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)
                return '/';
        else
                return '\\';
}

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;
}

#ifdef CONFIG_CIFS_STATS
#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);
}
#else

#define  cifs_stats_inc(field) do {} while (0)
#define  cifs_stats_bytes_written(tcon, bytes) do {} while (0)
#define  cifs_stats_bytes_read(tcon, bytes) do {} while (0)

#endif


/*
 * 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 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 */
        struct TCP_Server_Info *server; /* server corresponding to this mid */
        __u64 mid;              /* multiplex id */
        __u32 pid;              /* process id */
        __u32 sequence_number;  /* for CIFS signing */
        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 */
        void *callback_data;      /* general purpose pointer for callback */
        void *resp_buf;         /* pointer to received SMB header */
        int mid_state;  /* wish this were enum but can not pass to wait_event */
        __le16 command;         /* smb command code */
        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 */
};

/*      Make code in transport.c a little cleaner by moving
        update of optional stats into function below */
#ifdef CONFIG_CIFS_STATS2

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);
}

static inline void cifs_save_when_sent(struct mid_q_entry *mid)
{
        mid->when_sent = jiffies;
}
#else
static inline void cifs_in_send_inc(struct TCP_Server_Info *server)
{
}
static inline void cifs_in_send_dec(struct TCP_Server_Info *server)
{
}

static inline void cifs_num_waiters_inc(struct TCP_Server_Info *server)
{
}

static inline void cifs_num_waiters_dec(struct TCP_Server_Info *server)
{
}

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;
};

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

#define CIFS_FATTR_DFS_REFERRAL         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

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 timespec cf_atime;
        struct timespec cf_mtime;
        struct timespec cf_ctime;
};

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

#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

/* 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_ASYNC_OP         2    /* do not wait for response */
#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_RESP      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_OP_MASK     0x0380    /* mask request type */
#define   CIFS_HAS_CREDITS 0x0400    /* already has credits */

/* Security Flags: indicate type of session setup needed */
#define   CIFSSEC_MAY_SIGN      0x00001
#define   CIFSSEC_MAY_NTLM      0x00002
#define   CIFSSEC_MAY_NTLMV2    0x00004
#define   CIFSSEC_MAY_KRB5      0x00008
#ifdef CONFIG_CIFS_WEAK_PW_HASH
#define   CIFSSEC_MAY_LANMAN    0x00010
#define   CIFSSEC_MAY_PLNTXT    0x00020
#else
#define   CIFSSEC_MAY_LANMAN    0
#define   CIFSSEC_MAY_PLNTXT    0
#endif /* weak passwords */
#define   CIFSSEC_MAY_SEAL      0x00040 /* not supported yet */
#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_NTLM     0x02002
#define   CIFSSEC_MUST_NTLMV2   0x04004
#define   CIFSSEC_MUST_KRB5     0x08008
#ifdef CONFIG_CIFS_WEAK_PW_HASH
#define   CIFSSEC_MUST_LANMAN   0x10010
#define   CIFSSEC_MUST_PLNTXT   0x20020
#ifdef CONFIG_CIFS_UPCALL
#define   CIFSSEC_MASK          0xBF0BF /* allows weak security but also krb5 */
#else
#define   CIFSSEC_MASK          0xB70B7 /* current flags supported if weak */
#endif /* UPCALL */
#else /* do not allow weak pw hash */
#define   CIFSSEC_MUST_LANMAN   0
#define   CIFSSEC_MUST_PLNTXT   0
#ifdef CONFIG_CIFS_UPCALL
#define   CIFSSEC_MASK          0x8F08F /* flags supported if no weak allowed */
#else
#define   CIFSSEC_MASK          0x87087 /* flags supported if no weak allowed */
#endif /* UPCALL */
#endif /* WEAK_PW_HASH */
#define   CIFSSEC_MUST_SEAL     0x40040 /* not supported yet */
#define   CIFSSEC_MUST_NTLMSSP  0x80080 /* raw ntlmssp with ntlmv2 */

#define   CIFSSEC_DEF (CIFSSEC_MAY_SIGN | CIFSSEC_MAY_NTLMV2 | CIFSSEC_MAY_NTLMSSP)
#define   CIFSSEC_MAX (CIFSSEC_MUST_SIGN | CIFSSEC_MUST_NTLMV2)
#define   CIFSSEC_AUTH_MASK (CIFSSEC_MAY_NTLM | CIFSSEC_MAY_NTLMV2 | CIFSSEC_MAY_LANMAN | CIFSSEC_MAY_PLNTXT | 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.
 */

/****************************************************************************
 *  Locking notes.  All updates to global variables and lists should be
 *                  protected by spinlocks or semaphores.
 *
 *  Spinlocks
 *  ---------
 *  GlobalMid_Lock protects:
 *      list operations on pending_mid_q and oplockQ
 *      updates to XID counters, multiplex id  and SMB sequence numbers
 *  cifs_file_list_lock protects:
 *      list operations on tcp and SMB session lists and tCon lists
 *  f_owner.lock protects certain per file struct operations
 *  mapping->page_lock protects certain per page operations
 *
 *  Semaphores
 *  ----------
 *  sesSem     operations on smb session
 *  tconSem    operations on tree connection
 *  fh_sem      file handle reconnection operations
 *
 ****************************************************************************/

#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
 */
GLOBAL_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. Finally,
 * changes to the tcon->tidStatus should be done while holding this lock.
 */
GLOBAL_EXTERN spinlock_t                cifs_tcp_ses_lock;

/*
 * This lock protects the cifs_file->llist and cifs_file->flist
 * list operations, and updates to some flags (cifs_file->invalidHandle)
 * It will be moved to either use the tcon->stat_lock or equivalent later.
 * If cifs_tcp_ses_lock and the lock below are both needed to be held, then
 * the cifs_tcp_ses_lock must be grabbed first and released last.
 */
GLOBAL_EXTERN spinlock_t        cifs_file_list_lock;

#ifdef CONFIG_CIFS_DNOTIFY_EXPERIMENTAL /* unused temporarily */
/* Outstanding dir notify requests */
GLOBAL_EXTERN struct list_head GlobalDnotifyReqList;
/* DirNotify response queue */
GLOBAL_EXTERN struct list_head GlobalDnotifyRsp_Q;
#endif /* was needed for dnotify, and will be needed for inotify when VFS fix */

/*
 * Global transaction id (XID) information
 */
GLOBAL_EXTERN unsigned int GlobalCurrentXid;    /* protected by GlobalMid_Sem */
GLOBAL_EXTERN unsigned int GlobalTotalActiveXid; /* prot by GlobalMid_Sem */
GLOBAL_EXTERN unsigned int GlobalMaxActiveXid;  /* prot by GlobalMid_Sem */
GLOBAL_EXTERN spinlock_t GlobalMid_Lock;  /* protects above & list operations */
                                          /* on midQ entries */
/*
 *  Global counters, updated atomically
 */
GLOBAL_EXTERN atomic_t sesInfoAllocCount;
GLOBAL_EXTERN atomic_t tconInfoAllocCount;
GLOBAL_EXTERN atomic_t tcpSesAllocCount;
GLOBAL_EXTERN atomic_t tcpSesReconnectCount;
GLOBAL_EXTERN atomic_t tconInfoReconnectCount;

/* Various Debug counters */
GLOBAL_EXTERN atomic_t bufAllocCount;    /* current number allocated  */
#ifdef CONFIG_CIFS_STATS2
GLOBAL_EXTERN atomic_t totBufAllocCount; /* total allocated over all time */
GLOBAL_EXTERN atomic_t totSmBufAllocCount;
#endif
GLOBAL_EXTERN atomic_t smBufAllocCount;
GLOBAL_EXTERN atomic_t midCount;

/* Misc globals */
GLOBAL_EXTERN bool enable_oplocks; /* enable or disable oplocks */
GLOBAL_EXTERN bool lookupCacheEnabled;
GLOBAL_EXTERN unsigned int global_secflags;     /* if on, session setup sent
                                with more secure ntlmssp2 challenge/resp */
GLOBAL_EXTERN unsigned int sign_CIFS_PDUs;  /* enable smb packet signing */
GLOBAL_EXTERN bool linuxExtEnabled;/*enable Linux/Unix CIFS extensions*/
GLOBAL_EXTERN unsigned int CIFSMaxBufSize;  /* max size not including hdr */
GLOBAL_EXTERN unsigned int cifs_min_rcv;    /* min size of big ntwrk buf pool */
GLOBAL_EXTERN unsigned int cifs_min_small;  /* min size of small buf pool */
GLOBAL_EXTERN unsigned int cifs_max_pending; /* MAX requests at once to server*/

#ifdef CONFIG_CIFS_ACL
GLOBAL_EXTERN struct rb_root uidtree;
GLOBAL_EXTERN struct rb_root gidtree;
GLOBAL_EXTERN spinlock_t siduidlock;
GLOBAL_EXTERN spinlock_t sidgidlock;
GLOBAL_EXTERN struct rb_root siduidtree;
GLOBAL_EXTERN struct rb_root sidgidtree;
GLOBAL_EXTERN spinlock_t uidsidlock;
GLOBAL_EXTERN spinlock_t gidsidlock;
#endif /* CONFIG_CIFS_ACL */

void cifs_oplock_break(struct work_struct *work);

extern const struct slow_work_ops cifs_oplock_break_ops;
extern struct workqueue_struct *cifsiod_wq;
extern __u32 cifs_lock_secret;

extern mempool_t *cifs_mid_poolp;

/* Operations for different SMB versions */
#define SMB1_VERSION_STRING     "1.0"
extern struct smb_version_operations smb1_operations;
extern struct smb_version_values smb1_values;
#define SMB20_VERSION_STRING    "2.0"
extern struct smb_version_operations smb20_operations;
extern struct smb_version_values smb20_values;
#define SMB21_VERSION_STRING    "2.1"
extern struct smb_version_operations smb21_operations;
extern struct smb_version_values smb21_values;
#define SMB30_VERSION_STRING    "3.0"
extern struct smb_version_operations smb30_operations;
extern struct smb_version_values smb30_values;
#define SMB302_VERSION_STRING   "3.02"
/*extern struct smb_version_operations smb302_operations;*/ /* not needed yet */
extern struct smb_version_values smb302_values;
#define SMB311_VERSION_STRING   "3.1.1"
#define ALT_SMB311_VERSION_STRING "3.11"
extern struct smb_version_operations smb311_operations;
extern struct smb_version_values smb311_values;
#endif  /* _CIFS_GLOB_H */