cifs: add new cifsiod_wq workqueue

[GitHub/mt8127/android_kernel_alcatel_ttab.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/workqueue.h>
#include "cifs_fs_sb.h"
#include "cifsacl.h"
#include <crypto/internal/hash.h>
#include <linux/scatterlist.h>

/*
 * 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 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
#define MAX_SERVER_SIZE 15
#define MAX_SHARE_SIZE 80
#define MAX_USERNAME_SIZE 256   /* reasonable maximum for current servers */
#define MAX_PASSWORD_SIZE 512   /* max for windows seems to be 256 wide chars */

#define CIFS_MIN_RCV_POOL 4

/*
 * 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)

/* used to define string lengths for reversing unicode strings */
/*         (256+1)*2 = 514                                     */
/*           (max path length + 1 for null) * 2 for unicode    */
#define MAX_NAME 514

#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 {
        LANMAN = 0,                     /* Legacy LANMAN auth */
        NTLM,                   /* Legacy NTLM012 auth with NTLM hash */
        NTLMv2,                 /* Legacy NTLM auth with NTLMv2 hash */
        RawNTLMSSP,             /* NTLMSSP without SPNEGO, NTLMv2 hash */
/*      NTLMSSP, */ /* can use rawNTLMSSP instead of NTLMSSP via SPNEGO */
        Kerberos,               /* Kerberos via SPNEGO */
};

enum protocolEnum {
        TCP = 0,
        SCTP
        /* Netbios frames protocol not supported at this time */
};

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 sdesc *sdeschmacmd5;  /* ctxt to generate ntlmv2 hash, CR1 */
        struct sdesc *sdescmd5; /* ctxt to generate cifs/smb signature */
};

/* per smb session structure/fields */
struct ntlmssp_auth {
        __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
 *****************************************************************
 */

struct smb_vol {
        char *username;
        char *password;
        char *domainname;
        char *UNC;
        char *UNCip;
        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 */
        uid_t cred_uid;
        uid_t linux_uid;
        gid_t linux_gid;
        uid_t backupuid;
        gid_t backupgid;
        umode_t file_mode;
        umode_t dir_mode;
        unsigned secFlg;
        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 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 */
        unsigned int rsize;
        unsigned int wsize;
        bool sockopt_tcp_nodelay:1;
        unsigned short int port;
        unsigned long actimeo; /* attribute cache timeout (jiffies) */
        char *prepath;
        struct sockaddr_storage srcaddr; /* allow binding to a local IP */
        struct nls_table *local_nls;
};

#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_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));
}

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];
        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];
        char sec_mode;
        bool session_estab; /* mark when very first sess is established */
        u16 dialect; /* dialect index that server chose */
        enum securityEnum secType;
        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 max_vcs;   /* maximum number of smb sessions, at least
                                   those that can be specified uniquely with
                                   vcnumbers */
        int capabilities; /* allow 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 */
        /* 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 */
        struct kvec *iov;       /* reusable kvec array for receives */
        unsigned int nr_iov;    /* number of kvecs in array */
        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
};

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 int*
get_credits_field(struct TCP_Server_Info *server)
{
        /*
         * This will change to switch statement when we reserve slots for echos
         * and oplock breaks.
         */
        return &server->credits;
}

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 size_t
header_size(void)
{
        return sizeof(struct smb_hdr);
}

static inline size_t
max_header_size(void)
{
        return MAX_CIFS_HDR_SIZE;
}

/*
 * 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 */
        __u16 flags;
        __u16 vcnum;
        char *serverOS;         /* name of operating system underlying server */
        char *serverNOS;        /* name of network operating system of server */
        char *serverDomain;     /* security realm of server */
        int Suid;               /* remote smb uid  */
        uid_t linux_uid;        /* overriding owner of files on the mount */
        uid_t cred_uid;         /* owner of credentials */
        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 */
        bool need_reconnect:1; /* connection reset, uid now invalid */
};
/* no more than one of the following three session flags may be set */
#define CIFS_SES_NT4 1
#define CIFS_SES_OS2 2
#define CIFS_SES_W9X 4
/* following flag is set for old servers such as OS2 (and Win95?)
   which do not negotiate NTLM or POSIX dialects, but instead
   negotiate one of the older LANMAN dialects */
#define CIFS_SES_LANMAN 8
/*
 * 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 */
        __u16 tid;              /* The 2 byte tree id */
        __u16 Flags;            /* optional support bits */
        enum statusEnum tidStatus;
#ifdef CONFIG_CIFS_STATS
        atomic_t num_smbs_sent;
        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;
#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 need_reconnect:1; /* connection reset, tid now invalid */
#ifdef CONFIG_CIFS_FSCACHE
        u64 resource_id;                /* server resource id */
        struct fscache_cookie *fscache; /* cookie for share */
#endif
        /* 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;
        uid_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);

/*
 * 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;
        __u8 type;
        __u16 netfid;
};

/*
 * 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 cifsFileInfo {
        struct list_head tlist; /* pointer to next fid owned by tcon */
        struct list_head flist; /* next fid (file instance) for this inode */
        unsigned int uid;       /* allows finding which FileInfo structure */
        __u32 pid;              /* process id who opened file */
        __u16 netfid;           /* 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;
        __u32 pid;
        __u64 offset;
        unsigned int length;
        struct cifs_tcon *tcon;
};

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

void cifsFileInfo_put(struct cifsFileInfo *cifs_file);

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

struct cifsInodeInfo {
        struct list_head llist;         /* brlocks for this inode */
        bool can_cache_brlcks;
        struct mutex lock_mutex;        /* protect two 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 */
        bool clientCanCacheRead;        /* read oplock */
        bool clientCanCacheAll;         /* read and writebehind oplock */
        bool delete_pending;            /* DELETE_ON_CLOSE is set */
        bool invalid_mapping;           /* pagecache is invalid */
        unsigned long time;             /* jiffies of last update of inode */
        u64  server_eof;                /* current file size on server */
        u64  uniqueid;                  /* server inode number */
        u64  createtime;                /* creation time on server */
#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 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)
{
        int i;
        char old_delim;

        if (path == NULL)
                return;

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

        for (i = 0; path[i] != '\0'; i++) {
                if (path[i] == old_delim)
                        path[i] = 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

struct mid_q_entry;

/*
 * 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 */
        __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

struct cifs_fattr {
        u32             cf_flags;
        u32             cf_cifsattrs;
        u64             cf_uniqueid;
        u64             cf_eof;
        u64             cf_bytes;
        u64             cf_createtime;
        uid_t           cf_uid;
        gid_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 */

/* 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_NTLM | CIFSSEC_MAY_NTLMV2)
#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 unsigned int multiuser_mount; /* if enabled allows new sessions
                                to be established on existing mount if we
                                have the uid/password or Kerberos credential
                                or equivalent for current user */
/* enable or disable oplocks */
GLOBAL_EXTERN bool enable_oplocks;
GLOBAL_EXTERN unsigned int 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 unsigned int 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;

#endif  /* _CIFS_GLOB_H */