mm/vmscan.c: prevent useless kswapd loops

[linux/fpc-iii.git] / fs / cifs / smb1ops.c

/*
 *  SMB1 (CIFS) version specific operations
 *
 *  Copyright (c) 2012, Jeff Layton <jlayton@redhat.com>
 *
 *  This library is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License v2 as published
 *  by the Free Software Foundation.
 *
 *  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.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/pagemap.h>
#include <linux/vfs.h>
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifspdu.h"
#include "cifs_unicode.h"

/*
 * An NT cancel request header looks just like the original request except:
 *
 * The Command is SMB_COM_NT_CANCEL
 * The WordCount is zeroed out
 * The ByteCount is zeroed out
 *
 * This function mangles an existing request buffer into a
 * SMB_COM_NT_CANCEL request and then sends it.
 */
static int
send_nt_cancel(struct TCP_Server_Info *server, struct smb_rqst *rqst,
               struct mid_q_entry *mid)
{
        int rc = 0;
        struct smb_hdr *in_buf = (struct smb_hdr *)rqst->rq_iov[0].iov_base;

        /* -4 for RFC1001 length and +2 for BCC field */
        in_buf->smb_buf_length = cpu_to_be32(sizeof(struct smb_hdr) - 4  + 2);
        in_buf->Command = SMB_COM_NT_CANCEL;
        in_buf->WordCount = 0;
        put_bcc(0, in_buf);

        mutex_lock(&server->srv_mutex);
        rc = cifs_sign_smb(in_buf, server, &mid->sequence_number);
        if (rc) {
                mutex_unlock(&server->srv_mutex);
                return rc;
        }

        /*
         * The response to this call was already factored into the sequence
         * number when the call went out, so we must adjust it back downward
         * after signing here.
         */
        --server->sequence_number;
        rc = smb_send(server, in_buf, be32_to_cpu(in_buf->smb_buf_length));
        if (rc < 0)
                server->sequence_number--;

        mutex_unlock(&server->srv_mutex);

        cifs_dbg(FYI, "issued NT_CANCEL for mid %u, rc = %d\n",
                 get_mid(in_buf), rc);

        return rc;
}

static bool
cifs_compare_fids(struct cifsFileInfo *ob1, struct cifsFileInfo *ob2)
{
        return ob1->fid.netfid == ob2->fid.netfid;
}

static unsigned int
cifs_read_data_offset(char *buf)
{
        READ_RSP *rsp = (READ_RSP *)buf;
        return le16_to_cpu(rsp->DataOffset);
}

static unsigned int
cifs_read_data_length(char *buf, bool in_remaining)
{
        READ_RSP *rsp = (READ_RSP *)buf;
        /* It's a bug reading remaining data for SMB1 packets */
        WARN_ON(in_remaining);
        return (le16_to_cpu(rsp->DataLengthHigh) << 16) +
               le16_to_cpu(rsp->DataLength);
}

static struct mid_q_entry *
cifs_find_mid(struct TCP_Server_Info *server, char *buffer)
{
        struct smb_hdr *buf = (struct smb_hdr *)buffer;
        struct mid_q_entry *mid;

        spin_lock(&GlobalMid_Lock);
        list_for_each_entry(mid, &server->pending_mid_q, qhead) {
                if (compare_mid(mid->mid, buf) &&
                    mid->mid_state == MID_REQUEST_SUBMITTED &&
                    le16_to_cpu(mid->command) == buf->Command) {
                        kref_get(&mid->refcount);
                        spin_unlock(&GlobalMid_Lock);
                        return mid;
                }
        }
        spin_unlock(&GlobalMid_Lock);
        return NULL;
}

static void
cifs_add_credits(struct TCP_Server_Info *server, const unsigned int add,
                 const int optype)
{
        spin_lock(&server->req_lock);
        server->credits += add;
        server->in_flight--;
        spin_unlock(&server->req_lock);
        wake_up(&server->request_q);
}

static void
cifs_set_credits(struct TCP_Server_Info *server, const int val)
{
        spin_lock(&server->req_lock);
        server->credits = val;
        server->oplocks = val > 1 ? enable_oplocks : false;
        spin_unlock(&server->req_lock);
}

static int *
cifs_get_credits_field(struct TCP_Server_Info *server, const int optype)
{
        return &server->credits;
}

static unsigned int
cifs_get_credits(struct mid_q_entry *mid)
{
        return 1;
}

/*
 * Find a free multiplex id (SMB mid). Otherwise there could be
 * mid collisions which might cause problems, demultiplexing the
 * wrong response to this request. Multiplex ids could collide if
 * one of a series requests takes much longer than the others, or
 * if a very large number of long lived requests (byte range
 * locks or FindNotify requests) are pending. No more than
 * 64K-1 requests can be outstanding at one time. If no
 * mids are available, return zero. A future optimization
 * could make the combination of mids and uid the key we use
 * to demultiplex on (rather than mid alone).
 * In addition to the above check, the cifs demultiplex
 * code already used the command code as a secondary
 * check of the frame and if signing is negotiated the
 * response would be discarded if the mid were the same
 * but the signature was wrong. Since the mid is not put in the
 * pending queue until later (when it is about to be dispatched)
 * we do have to limit the number of outstanding requests
 * to somewhat less than 64K-1 although it is hard to imagine
 * so many threads being in the vfs at one time.
 */
static __u64
cifs_get_next_mid(struct TCP_Server_Info *server)
{
        __u64 mid = 0;
        __u16 last_mid, cur_mid;
        bool collision;

        spin_lock(&GlobalMid_Lock);

        /* mid is 16 bit only for CIFS/SMB */
        cur_mid = (__u16)((server->CurrentMid) & 0xffff);
        /* we do not want to loop forever */
        last_mid = cur_mid;
        cur_mid++;

        /*
         * This nested loop looks more expensive than it is.
         * In practice the list of pending requests is short,
         * fewer than 50, and the mids are likely to be unique
         * on the first pass through the loop unless some request
         * takes longer than the 64 thousand requests before it
         * (and it would also have to have been a request that
         * did not time out).
         */
        while (cur_mid != last_mid) {
                struct mid_q_entry *mid_entry;
                unsigned int num_mids;

                collision = false;
                if (cur_mid == 0)
                        cur_mid++;

                num_mids = 0;
                list_for_each_entry(mid_entry, &server->pending_mid_q, qhead) {
                        ++num_mids;
                        if (mid_entry->mid == cur_mid &&
                            mid_entry->mid_state == MID_REQUEST_SUBMITTED) {
                                /* This mid is in use, try a different one */
                                collision = true;
                                break;
                        }
                }

                /*
                 * if we have more than 32k mids in the list, then something
                 * is very wrong. Possibly a local user is trying to DoS the
                 * box by issuing long-running calls and SIGKILL'ing them. If
                 * we get to 2^16 mids then we're in big trouble as this
                 * function could loop forever.
                 *
                 * Go ahead and assign out the mid in this situation, but force
                 * an eventual reconnect to clean out the pending_mid_q.
                 */
                if (num_mids > 32768)
                        server->tcpStatus = CifsNeedReconnect;

                if (!collision) {
                        mid = (__u64)cur_mid;
                        server->CurrentMid = mid;
                        break;
                }
                cur_mid++;
        }
        spin_unlock(&GlobalMid_Lock);
        return mid;
}

/*
        return codes:
                0       not a transact2, or all data present
                >0      transact2 with that much data missing
                -EINVAL invalid transact2
 */
static int
check2ndT2(char *buf)
{
        struct smb_hdr *pSMB = (struct smb_hdr *)buf;
        struct smb_t2_rsp *pSMBt;
        int remaining;
        __u16 total_data_size, data_in_this_rsp;

        if (pSMB->Command != SMB_COM_TRANSACTION2)
                return 0;

        /* check for plausible wct, bcc and t2 data and parm sizes */
        /* check for parm and data offset going beyond end of smb */
        if (pSMB->WordCount != 10) { /* coalesce_t2 depends on this */
                cifs_dbg(FYI, "invalid transact2 word count\n");
                return -EINVAL;
        }

        pSMBt = (struct smb_t2_rsp *)pSMB;

        total_data_size = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
        data_in_this_rsp = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);

        if (total_data_size == data_in_this_rsp)
                return 0;
        else if (total_data_size < data_in_this_rsp) {
                cifs_dbg(FYI, "total data %d smaller than data in frame %d\n",
                         total_data_size, data_in_this_rsp);
                return -EINVAL;
        }

        remaining = total_data_size - data_in_this_rsp;

        cifs_dbg(FYI, "missing %d bytes from transact2, check next response\n",
                 remaining);
        if (total_data_size > CIFSMaxBufSize) {
                cifs_dbg(VFS, "TotalDataSize %d is over maximum buffer %d\n",
                         total_data_size, CIFSMaxBufSize);
                return -EINVAL;
        }
        return remaining;
}

static int
coalesce_t2(char *second_buf, struct smb_hdr *target_hdr)
{
        struct smb_t2_rsp *pSMBs = (struct smb_t2_rsp *)second_buf;
        struct smb_t2_rsp *pSMBt  = (struct smb_t2_rsp *)target_hdr;
        char *data_area_of_tgt;
        char *data_area_of_src;
        int remaining;
        unsigned int byte_count, total_in_tgt;
        __u16 tgt_total_cnt, src_total_cnt, total_in_src;

        src_total_cnt = get_unaligned_le16(&pSMBs->t2_rsp.TotalDataCount);
        tgt_total_cnt = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);

        if (tgt_total_cnt != src_total_cnt)
                cifs_dbg(FYI, "total data count of primary and secondary t2 differ source=%hu target=%hu\n",
                         src_total_cnt, tgt_total_cnt);

        total_in_tgt = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);

        remaining = tgt_total_cnt - total_in_tgt;

        if (remaining < 0) {
                cifs_dbg(FYI, "Server sent too much data. tgt_total_cnt=%hu total_in_tgt=%u\n",
                         tgt_total_cnt, total_in_tgt);
                return -EPROTO;
        }

        if (remaining == 0) {
                /* nothing to do, ignore */
                cifs_dbg(FYI, "no more data remains\n");
                return 0;
        }

        total_in_src = get_unaligned_le16(&pSMBs->t2_rsp.DataCount);
        if (remaining < total_in_src)
                cifs_dbg(FYI, "transact2 2nd response contains too much data\n");

        /* find end of first SMB data area */
        data_area_of_tgt = (char *)&pSMBt->hdr.Protocol +
                                get_unaligned_le16(&pSMBt->t2_rsp.DataOffset);

        /* validate target area */
        data_area_of_src = (char *)&pSMBs->hdr.Protocol +
                                get_unaligned_le16(&pSMBs->t2_rsp.DataOffset);

        data_area_of_tgt += total_in_tgt;

        total_in_tgt += total_in_src;
        /* is the result too big for the field? */
        if (total_in_tgt > USHRT_MAX) {
                cifs_dbg(FYI, "coalesced DataCount too large (%u)\n",
                         total_in_tgt);
                return -EPROTO;
        }
        put_unaligned_le16(total_in_tgt, &pSMBt->t2_rsp.DataCount);

        /* fix up the BCC */
        byte_count = get_bcc(target_hdr);
        byte_count += total_in_src;
        /* is the result too big for the field? */
        if (byte_count > USHRT_MAX) {
                cifs_dbg(FYI, "coalesced BCC too large (%u)\n", byte_count);
                return -EPROTO;
        }
        put_bcc(byte_count, target_hdr);

        byte_count = be32_to_cpu(target_hdr->smb_buf_length);
        byte_count += total_in_src;
        /* don't allow buffer to overflow */
        if (byte_count > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
                cifs_dbg(FYI, "coalesced BCC exceeds buffer size (%u)\n",
                         byte_count);
                return -ENOBUFS;
        }
        target_hdr->smb_buf_length = cpu_to_be32(byte_count);

        /* copy second buffer into end of first buffer */
        memcpy(data_area_of_tgt, data_area_of_src, total_in_src);

        if (remaining != total_in_src) {
                /* more responses to go */
                cifs_dbg(FYI, "waiting for more secondary responses\n");
                return 1;
        }

        /* we are done */
        cifs_dbg(FYI, "found the last secondary response\n");
        return 0;
}

static void
cifs_downgrade_oplock(struct TCP_Server_Info *server,
                        struct cifsInodeInfo *cinode, bool set_level2)
{
        if (set_level2)
                cifs_set_oplock_level(cinode, OPLOCK_READ);
        else
                cifs_set_oplock_level(cinode, 0);
}

static bool
cifs_check_trans2(struct mid_q_entry *mid, struct TCP_Server_Info *server,
                  char *buf, int malformed)
{
        if (malformed)
                return false;
        if (check2ndT2(buf) <= 0)
                return false;
        mid->multiRsp = true;
        if (mid->resp_buf) {
                /* merge response - fix up 1st*/
                malformed = coalesce_t2(buf, mid->resp_buf);
                if (malformed > 0)
                        return true;
                /* All parts received or packet is malformed. */
                mid->multiEnd = true;
                dequeue_mid(mid, malformed);
                return true;
        }
        if (!server->large_buf) {
                /*FIXME: switch to already allocated largebuf?*/
                cifs_dbg(VFS, "1st trans2 resp needs bigbuf\n");
        } else {
                /* Have first buffer */
                mid->resp_buf = buf;
                mid->large_buf = true;
                server->bigbuf = NULL;
        }
        return true;
}

static bool
cifs_need_neg(struct TCP_Server_Info *server)
{
        return server->maxBuf == 0;
}

static int
cifs_negotiate(const unsigned int xid, struct cifs_ses *ses)
{
        int rc;
        rc = CIFSSMBNegotiate(xid, ses);
        if (rc == -EAGAIN) {
                /* retry only once on 1st time connection */
                set_credits(ses->server, 1);
                rc = CIFSSMBNegotiate(xid, ses);
                if (rc == -EAGAIN)
                        rc = -EHOSTDOWN;
        }
        return rc;
}

static unsigned int
cifs_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
{
        __u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int wsize;

        /* start with specified wsize, or default */
        if (volume_info->wsize)
                wsize = volume_info->wsize;
        else if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
                wsize = CIFS_DEFAULT_IOSIZE;
        else
                wsize = CIFS_DEFAULT_NON_POSIX_WSIZE;

        /* can server support 24-bit write sizes? (via UNIX extensions) */
        if (!tcon->unix_ext || !(unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
                wsize = min_t(unsigned int, wsize, CIFS_MAX_RFC1002_WSIZE);

        /*
         * no CAP_LARGE_WRITE_X or is signing enabled without CAP_UNIX set?
         * Limit it to max buffer offered by the server, minus the size of the
         * WRITEX header, not including the 4 byte RFC1001 length.
         */
        if (!(server->capabilities & CAP_LARGE_WRITE_X) ||
            (!(server->capabilities & CAP_UNIX) && server->sign))
                wsize = min_t(unsigned int, wsize,
                                server->maxBuf - sizeof(WRITE_REQ) + 4);

        /* hard limit of CIFS_MAX_WSIZE */
        wsize = min_t(unsigned int, wsize, CIFS_MAX_WSIZE);

        return wsize;
}

static unsigned int
cifs_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
{
        __u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int rsize, defsize;

        /*
         * Set default value...
         *
         * HACK alert! Ancient servers have very small buffers. Even though
         * MS-CIFS indicates that servers are only limited by the client's
         * bufsize for reads, testing against win98se shows that it throws
         * INVALID_PARAMETER errors if you try to request too large a read.
         * OS/2 just sends back short reads.
         *
         * If the server doesn't advertise CAP_LARGE_READ_X, then assume that
         * it can't handle a read request larger than its MaxBufferSize either.
         */
        if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_READ_CAP))
                defsize = CIFS_DEFAULT_IOSIZE;
        else if (server->capabilities & CAP_LARGE_READ_X)
                defsize = CIFS_DEFAULT_NON_POSIX_RSIZE;
        else
                defsize = server->maxBuf - sizeof(READ_RSP);

        rsize = volume_info->rsize ? volume_info->rsize : defsize;

        /*
         * no CAP_LARGE_READ_X? Then MS-CIFS states that we must limit this to
         * the client's MaxBufferSize.
         */
        if (!(server->capabilities & CAP_LARGE_READ_X))
                rsize = min_t(unsigned int, CIFSMaxBufSize, rsize);

        /* hard limit of CIFS_MAX_RSIZE */
        rsize = min_t(unsigned int, rsize, CIFS_MAX_RSIZE);

        return rsize;
}

static void
cifs_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon)
{
        CIFSSMBQFSDeviceInfo(xid, tcon);
        CIFSSMBQFSAttributeInfo(xid, tcon);
}

static int
cifs_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
                        struct cifs_sb_info *cifs_sb, const char *full_path)
{
        int rc;
        FILE_ALL_INFO *file_info;

        file_info = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
        if (file_info == NULL)
                return -ENOMEM;

        rc = CIFSSMBQPathInfo(xid, tcon, full_path, file_info,
                              0 /* not legacy */, cifs_sb->local_nls,
                              cifs_remap(cifs_sb));

        if (rc == -EOPNOTSUPP || rc == -EINVAL)
                rc = SMBQueryInformation(xid, tcon, full_path, file_info,
                                cifs_sb->local_nls, cifs_remap(cifs_sb));
        kfree(file_info);
        return rc;
}

static int
cifs_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
                     struct cifs_sb_info *cifs_sb, const char *full_path,
                     FILE_ALL_INFO *data, bool *adjustTZ, bool *symlink)
{
        int rc;

        *symlink = false;

        /* could do find first instead but this returns more info */
        rc = CIFSSMBQPathInfo(xid, tcon, full_path, data, 0 /* not legacy */,
                              cifs_sb->local_nls, cifs_remap(cifs_sb));
        /*
         * BB optimize code so we do not make the above call when server claims
         * no NT SMB support and the above call failed at least once - set flag
         * in tcon or mount.
         */
        if ((rc == -EOPNOTSUPP) || (rc == -EINVAL)) {
                rc = SMBQueryInformation(xid, tcon, full_path, data,
                                         cifs_sb->local_nls,
                                         cifs_remap(cifs_sb));
                *adjustTZ = true;
        }

        if (!rc && (le32_to_cpu(data->Attributes) & ATTR_REPARSE)) {
                int tmprc;
                int oplock = 0;
                struct cifs_fid fid;
                struct cifs_open_parms oparms;

                oparms.tcon = tcon;
                oparms.cifs_sb = cifs_sb;
                oparms.desired_access = FILE_READ_ATTRIBUTES;
                oparms.create_options = 0;
                oparms.disposition = FILE_OPEN;
                oparms.path = full_path;
                oparms.fid = &fid;
                oparms.reconnect = false;

                /* Need to check if this is a symbolic link or not */
                tmprc = CIFS_open(xid, &oparms, &oplock, NULL);
                if (tmprc == -EOPNOTSUPP)
                        *symlink = true;
                else if (tmprc == 0)
                        CIFSSMBClose(xid, tcon, fid.netfid);
        }

        return rc;
}

static int
cifs_get_srv_inum(const unsigned int xid, struct cifs_tcon *tcon,
                  struct cifs_sb_info *cifs_sb, const char *full_path,
                  u64 *uniqueid, FILE_ALL_INFO *data)
{
        /*
         * We can not use the IndexNumber field by default from Windows or
         * Samba (in ALL_INFO buf) but we can request it explicitly. The SNIA
         * CIFS spec claims that this value is unique within the scope of a
         * share, and the windows docs hint that it's actually unique
         * per-machine.
         *
         * There may be higher info levels that work but are there Windows
         * server or network appliances for which IndexNumber field is not
         * guaranteed unique?
         */
        return CIFSGetSrvInodeNumber(xid, tcon, full_path, uniqueid,
                                     cifs_sb->local_nls,
                                     cifs_remap(cifs_sb));
}

static int
cifs_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
                     struct cifs_fid *fid, FILE_ALL_INFO *data)
{
        return CIFSSMBQFileInfo(xid, tcon, fid->netfid, data);
}

static void
cifs_clear_stats(struct cifs_tcon *tcon)
{
        atomic_set(&tcon->stats.cifs_stats.num_writes, 0);
        atomic_set(&tcon->stats.cifs_stats.num_reads, 0);
        atomic_set(&tcon->stats.cifs_stats.num_flushes, 0);
        atomic_set(&tcon->stats.cifs_stats.num_oplock_brks, 0);
        atomic_set(&tcon->stats.cifs_stats.num_opens, 0);
        atomic_set(&tcon->stats.cifs_stats.num_posixopens, 0);
        atomic_set(&tcon->stats.cifs_stats.num_posixmkdirs, 0);
        atomic_set(&tcon->stats.cifs_stats.num_closes, 0);
        atomic_set(&tcon->stats.cifs_stats.num_deletes, 0);
        atomic_set(&tcon->stats.cifs_stats.num_mkdirs, 0);
        atomic_set(&tcon->stats.cifs_stats.num_rmdirs, 0);
        atomic_set(&tcon->stats.cifs_stats.num_renames, 0);
        atomic_set(&tcon->stats.cifs_stats.num_t2renames, 0);
        atomic_set(&tcon->stats.cifs_stats.num_ffirst, 0);
        atomic_set(&tcon->stats.cifs_stats.num_fnext, 0);
        atomic_set(&tcon->stats.cifs_stats.num_fclose, 0);
        atomic_set(&tcon->stats.cifs_stats.num_hardlinks, 0);
        atomic_set(&tcon->stats.cifs_stats.num_symlinks, 0);
        atomic_set(&tcon->stats.cifs_stats.num_locks, 0);
        atomic_set(&tcon->stats.cifs_stats.num_acl_get, 0);
        atomic_set(&tcon->stats.cifs_stats.num_acl_set, 0);
}

static void
cifs_print_stats(struct seq_file *m, struct cifs_tcon *tcon)
{
        seq_printf(m, " Oplocks breaks: %d",
                   atomic_read(&tcon->stats.cifs_stats.num_oplock_brks));
        seq_printf(m, "\nReads:  %d Bytes: %llu",
                   atomic_read(&tcon->stats.cifs_stats.num_reads),
                   (long long)(tcon->bytes_read));
        seq_printf(m, "\nWrites: %d Bytes: %llu",
                   atomic_read(&tcon->stats.cifs_stats.num_writes),
                   (long long)(tcon->bytes_written));
        seq_printf(m, "\nFlushes: %d",
                   atomic_read(&tcon->stats.cifs_stats.num_flushes));
        seq_printf(m, "\nLocks: %d HardLinks: %d Symlinks: %d",
                   atomic_read(&tcon->stats.cifs_stats.num_locks),
                   atomic_read(&tcon->stats.cifs_stats.num_hardlinks),
                   atomic_read(&tcon->stats.cifs_stats.num_symlinks));
        seq_printf(m, "\nOpens: %d Closes: %d Deletes: %d",
                   atomic_read(&tcon->stats.cifs_stats.num_opens),
                   atomic_read(&tcon->stats.cifs_stats.num_closes),
                   atomic_read(&tcon->stats.cifs_stats.num_deletes));
        seq_printf(m, "\nPosix Opens: %d Posix Mkdirs: %d",
                   atomic_read(&tcon->stats.cifs_stats.num_posixopens),
                   atomic_read(&tcon->stats.cifs_stats.num_posixmkdirs));
        seq_printf(m, "\nMkdirs: %d Rmdirs: %d",
                   atomic_read(&tcon->stats.cifs_stats.num_mkdirs),
                   atomic_read(&tcon->stats.cifs_stats.num_rmdirs));
        seq_printf(m, "\nRenames: %d T2 Renames %d",
                   atomic_read(&tcon->stats.cifs_stats.num_renames),
                   atomic_read(&tcon->stats.cifs_stats.num_t2renames));
        seq_printf(m, "\nFindFirst: %d FNext %d FClose %d",
                   atomic_read(&tcon->stats.cifs_stats.num_ffirst),
                   atomic_read(&tcon->stats.cifs_stats.num_fnext),
                   atomic_read(&tcon->stats.cifs_stats.num_fclose));
}

static void
cifs_mkdir_setinfo(struct inode *inode, const char *full_path,
                   struct cifs_sb_info *cifs_sb, struct cifs_tcon *tcon,
                   const unsigned int xid)
{
        FILE_BASIC_INFO info;
        struct cifsInodeInfo *cifsInode;
        u32 dosattrs;
        int rc;

        memset(&info, 0, sizeof(info));
        cifsInode = CIFS_I(inode);
        dosattrs = cifsInode->cifsAttrs|ATTR_READONLY;
        info.Attributes = cpu_to_le32(dosattrs);
        rc = CIFSSMBSetPathInfo(xid, tcon, full_path, &info, cifs_sb->local_nls,
                                cifs_remap(cifs_sb));
        if (rc == 0)
                cifsInode->cifsAttrs = dosattrs;
}

static int
cifs_open_file(const unsigned int xid, struct cifs_open_parms *oparms,
               __u32 *oplock, FILE_ALL_INFO *buf)
{
        if (!(oparms->tcon->ses->capabilities & CAP_NT_SMBS))
                return SMBLegacyOpen(xid, oparms->tcon, oparms->path,
                                     oparms->disposition,
                                     oparms->desired_access,
                                     oparms->create_options,
                                     &oparms->fid->netfid, oplock, buf,
                                     oparms->cifs_sb->local_nls,
                                     cifs_remap(oparms->cifs_sb));
        return CIFS_open(xid, oparms, oplock, buf);
}

static void
cifs_set_fid(struct cifsFileInfo *cfile, struct cifs_fid *fid, __u32 oplock)
{
        struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
        cfile->fid.netfid = fid->netfid;
        cifs_set_oplock_level(cinode, oplock);
        cinode->can_cache_brlcks = CIFS_CACHE_WRITE(cinode);
}

static void
cifs_close_file(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifs_fid *fid)
{
        CIFSSMBClose(xid, tcon, fid->netfid);
}

static int
cifs_flush_file(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifs_fid *fid)
{
        return CIFSSMBFlush(xid, tcon, fid->netfid);
}

static int
cifs_sync_read(const unsigned int xid, struct cifs_fid *pfid,
               struct cifs_io_parms *parms, unsigned int *bytes_read,
               char **buf, int *buf_type)
{
        parms->netfid = pfid->netfid;
        return CIFSSMBRead(xid, parms, bytes_read, buf, buf_type);
}

static int
cifs_sync_write(const unsigned int xid, struct cifs_fid *pfid,
                struct cifs_io_parms *parms, unsigned int *written,
                struct kvec *iov, unsigned long nr_segs)
{

        parms->netfid = pfid->netfid;
        return CIFSSMBWrite2(xid, parms, written, iov, nr_segs);
}

static int
smb_set_file_info(struct inode *inode, const char *full_path,
                  FILE_BASIC_INFO *buf, const unsigned int xid)
{
        int oplock = 0;
        int rc;
        __u32 netpid;
        struct cifs_fid fid;
        struct cifs_open_parms oparms;
        struct cifsFileInfo *open_file;
        struct cifsInodeInfo *cinode = CIFS_I(inode);
        struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
        struct tcon_link *tlink = NULL;
        struct cifs_tcon *tcon;

        /* if the file is already open for write, just use that fileid */
        open_file = find_writable_file(cinode, true);
        if (open_file) {
                fid.netfid = open_file->fid.netfid;
                netpid = open_file->pid;
                tcon = tlink_tcon(open_file->tlink);
                goto set_via_filehandle;
        }

        tlink = cifs_sb_tlink(cifs_sb);
        if (IS_ERR(tlink)) {
                rc = PTR_ERR(tlink);
                tlink = NULL;
                goto out;
        }
        tcon = tlink_tcon(tlink);

        rc = CIFSSMBSetPathInfo(xid, tcon, full_path, buf, cifs_sb->local_nls,
                                cifs_remap(cifs_sb));
        if (rc == 0) {
                cinode->cifsAttrs = le32_to_cpu(buf->Attributes);
                goto out;
        } else if (rc != -EOPNOTSUPP && rc != -EINVAL) {
                goto out;
        }

        oparms.tcon = tcon;
        oparms.cifs_sb = cifs_sb;
        oparms.desired_access = SYNCHRONIZE | FILE_WRITE_ATTRIBUTES;
        oparms.create_options = CREATE_NOT_DIR;
        oparms.disposition = FILE_OPEN;
        oparms.path = full_path;
        oparms.fid = &fid;
        oparms.reconnect = false;

        cifs_dbg(FYI, "calling SetFileInfo since SetPathInfo for times not supported by this server\n");
        rc = CIFS_open(xid, &oparms, &oplock, NULL);
        if (rc != 0) {
                if (rc == -EIO)
                        rc = -EINVAL;
                goto out;
        }

        netpid = current->tgid;

set_via_filehandle:
        rc = CIFSSMBSetFileInfo(xid, tcon, buf, fid.netfid, netpid);
        if (!rc)
                cinode->cifsAttrs = le32_to_cpu(buf->Attributes);

        if (open_file == NULL)
                CIFSSMBClose(xid, tcon, fid.netfid);
        else
                cifsFileInfo_put(open_file);
out:
        if (tlink != NULL)
                cifs_put_tlink(tlink);
        return rc;
}

static int
cifs_set_compression(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile)
{
        return CIFSSMB_set_compression(xid, tcon, cfile->fid.netfid);
}

static int
cifs_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
                     const char *path, struct cifs_sb_info *cifs_sb,
                     struct cifs_fid *fid, __u16 search_flags,
                     struct cifs_search_info *srch_inf)
{
        int rc;

        rc = CIFSFindFirst(xid, tcon, path, cifs_sb,
                           &fid->netfid, search_flags, srch_inf, true);
        if (rc)
                cifs_dbg(FYI, "find first failed=%d\n", rc);
        return rc;
}

static int
cifs_query_dir_next(const unsigned int xid, struct cifs_tcon *tcon,
                    struct cifs_fid *fid, __u16 search_flags,
                    struct cifs_search_info *srch_inf)
{
        return CIFSFindNext(xid, tcon, fid->netfid, search_flags, srch_inf);
}

static int
cifs_close_dir(const unsigned int xid, struct cifs_tcon *tcon,
               struct cifs_fid *fid)
{
        return CIFSFindClose(xid, tcon, fid->netfid);
}

static int
cifs_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
                     struct cifsInodeInfo *cinode)
{
        return CIFSSMBLock(0, tcon, fid->netfid, current->tgid, 0, 0, 0, 0,
                           LOCKING_ANDX_OPLOCK_RELEASE, false,
                           CIFS_CACHE_READ(cinode) ? 1 : 0);
}

static int
cifs_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
             struct kstatfs *buf)
{
        int rc = -EOPNOTSUPP;

        buf->f_type = CIFS_MAGIC_NUMBER;

        /*
         * We could add a second check for a QFS Unix capability bit
         */
        if ((tcon->ses->capabilities & CAP_UNIX) &&
            (CIFS_POSIX_EXTENSIONS & le64_to_cpu(tcon->fsUnixInfo.Capability)))
                rc = CIFSSMBQFSPosixInfo(xid, tcon, buf);

        /*
         * Only need to call the old QFSInfo if failed on newer one,
         * e.g. by OS/2.
         **/
        if (rc && (tcon->ses->capabilities & CAP_NT_SMBS))
                rc = CIFSSMBQFSInfo(xid, tcon, buf);

        /*
         * Some old Windows servers also do not support level 103, retry with
         * older level one if old server failed the previous call or we
         * bypassed it because we detected that this was an older LANMAN sess
         */
        if (rc)
                rc = SMBOldQFSInfo(xid, tcon, buf);
        return rc;
}

static int
cifs_mand_lock(const unsigned int xid, struct cifsFileInfo *cfile, __u64 offset,
               __u64 length, __u32 type, int lock, int unlock, bool wait)
{
        return CIFSSMBLock(xid, tlink_tcon(cfile->tlink), cfile->fid.netfid,
                           current->tgid, length, offset, unlock, lock,
                           (__u8)type, wait, 0);
}

static int
cifs_unix_dfs_readlink(const unsigned int xid, struct cifs_tcon *tcon,
                       const unsigned char *searchName, char **symlinkinfo,
                       const struct nls_table *nls_codepage)
{
#ifdef CONFIG_CIFS_DFS_UPCALL
        int rc;
        unsigned int num_referrals = 0;
        struct dfs_info3_param *referrals = NULL;

        rc = get_dfs_path(xid, tcon->ses, searchName, nls_codepage,
                          &num_referrals, &referrals, 0);

        if (!rc && num_referrals > 0) {
                *symlinkinfo = kstrndup(referrals->node_name,
                                        strlen(referrals->node_name),
                                        GFP_KERNEL);
                if (!*symlinkinfo)
                        rc = -ENOMEM;
                free_dfs_info_array(referrals, num_referrals);
        }
        return rc;
#else /* No DFS support */
        return -EREMOTE;
#endif
}

static int
cifs_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
                   const char *full_path, char **target_path,
                   struct cifs_sb_info *cifs_sb)
{
        int rc;
        int oplock = 0;
        struct cifs_fid fid;
        struct cifs_open_parms oparms;

        cifs_dbg(FYI, "%s: path: %s\n", __func__, full_path);

        /* Check for unix extensions */
        if (cap_unix(tcon->ses)) {
                rc = CIFSSMBUnixQuerySymLink(xid, tcon, full_path, target_path,
                                             cifs_sb->local_nls,
                                             cifs_remap(cifs_sb));
                if (rc == -EREMOTE)
                        rc = cifs_unix_dfs_readlink(xid, tcon, full_path,
                                                    target_path,
                                                    cifs_sb->local_nls);

                goto out;
        }

        oparms.tcon = tcon;
        oparms.cifs_sb = cifs_sb;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.create_options = OPEN_REPARSE_POINT;
        oparms.disposition = FILE_OPEN;
        oparms.path = full_path;
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = CIFS_open(xid, &oparms, &oplock, NULL);
        if (rc)
                goto out;

        rc = CIFSSMBQuerySymLink(xid, tcon, fid.netfid, target_path,
                                 cifs_sb->local_nls);
        if (rc)
                goto out_close;

        convert_delimiter(*target_path, '/');
out_close:
        CIFSSMBClose(xid, tcon, fid.netfid);
out:
        if (!rc)
                cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);
        return rc;
}

static bool
cifs_is_read_op(__u32 oplock)
{
        return oplock == OPLOCK_READ;
}

static unsigned int
cifs_wp_retry_size(struct inode *inode)
{
        return CIFS_SB(inode->i_sb)->wsize;
}

static bool
cifs_dir_needs_close(struct cifsFileInfo *cfile)
{
        return !cfile->srch_inf.endOfSearch && !cfile->invalidHandle;
}

static bool
cifs_can_echo(struct TCP_Server_Info *server)
{
        if (server->tcpStatus == CifsGood)
                return true;

        return false;
}

struct smb_version_operations smb1_operations = {
        .send_cancel = send_nt_cancel,
        .compare_fids = cifs_compare_fids,
        .setup_request = cifs_setup_request,
        .setup_async_request = cifs_setup_async_request,
        .check_receive = cifs_check_receive,
        .add_credits = cifs_add_credits,
        .set_credits = cifs_set_credits,
        .get_credits_field = cifs_get_credits_field,
        .get_credits = cifs_get_credits,
        .wait_mtu_credits = cifs_wait_mtu_credits,
        .get_next_mid = cifs_get_next_mid,
        .read_data_offset = cifs_read_data_offset,
        .read_data_length = cifs_read_data_length,
        .map_error = map_smb_to_linux_error,
        .find_mid = cifs_find_mid,
        .check_message = checkSMB,
        .dump_detail = cifs_dump_detail,
        .clear_stats = cifs_clear_stats,
        .print_stats = cifs_print_stats,
        .is_oplock_break = is_valid_oplock_break,
        .downgrade_oplock = cifs_downgrade_oplock,
        .check_trans2 = cifs_check_trans2,
        .need_neg = cifs_need_neg,
        .negotiate = cifs_negotiate,
        .negotiate_wsize = cifs_negotiate_wsize,
        .negotiate_rsize = cifs_negotiate_rsize,
        .sess_setup = CIFS_SessSetup,
        .logoff = CIFSSMBLogoff,
        .tree_connect = CIFSTCon,
        .tree_disconnect = CIFSSMBTDis,
        .get_dfs_refer = CIFSGetDFSRefer,
        .qfs_tcon = cifs_qfs_tcon,
        .is_path_accessible = cifs_is_path_accessible,
        .can_echo = cifs_can_echo,
        .query_path_info = cifs_query_path_info,
        .query_file_info = cifs_query_file_info,
        .get_srv_inum = cifs_get_srv_inum,
        .set_path_size = CIFSSMBSetEOF,
        .set_file_size = CIFSSMBSetFileSize,
        .set_file_info = smb_set_file_info,
        .set_compression = cifs_set_compression,
        .echo = CIFSSMBEcho,
        .mkdir = CIFSSMBMkDir,
        .mkdir_setinfo = cifs_mkdir_setinfo,
        .rmdir = CIFSSMBRmDir,
        .unlink = CIFSSMBDelFile,
        .rename_pending_delete = cifs_rename_pending_delete,
        .rename = CIFSSMBRename,
        .create_hardlink = CIFSCreateHardLink,
        .query_symlink = cifs_query_symlink,
        .open = cifs_open_file,
        .set_fid = cifs_set_fid,
        .close = cifs_close_file,
        .flush = cifs_flush_file,
        .async_readv = cifs_async_readv,
        .async_writev = cifs_async_writev,
        .sync_read = cifs_sync_read,
        .sync_write = cifs_sync_write,
        .query_dir_first = cifs_query_dir_first,
        .query_dir_next = cifs_query_dir_next,
        .close_dir = cifs_close_dir,
        .calc_smb_size = smbCalcSize,
        .oplock_response = cifs_oplock_response,
        .queryfs = cifs_queryfs,
        .mand_lock = cifs_mand_lock,
        .mand_unlock_range = cifs_unlock_range,
        .push_mand_locks = cifs_push_mandatory_locks,
        .query_mf_symlink = cifs_query_mf_symlink,
        .create_mf_symlink = cifs_create_mf_symlink,
        .is_read_op = cifs_is_read_op,
        .wp_retry_size = cifs_wp_retry_size,
        .dir_needs_close = cifs_dir_needs_close,
        .select_sectype = cifs_select_sectype,
#ifdef CONFIG_CIFS_XATTR
        .query_all_EAs = CIFSSMBQAllEAs,
        .set_EA = CIFSSMBSetEA,
#endif /* CIFS_XATTR */
#ifdef CONFIG_CIFS_ACL
        .get_acl = get_cifs_acl,
        .get_acl_by_fid = get_cifs_acl_by_fid,
        .set_acl = set_cifs_acl,
#endif /* CIFS_ACL */
};

struct smb_version_values smb1_values = {
        .version_string = SMB1_VERSION_STRING,
        .large_lock_type = LOCKING_ANDX_LARGE_FILES,
        .exclusive_lock_type = 0,
        .shared_lock_type = LOCKING_ANDX_SHARED_LOCK,
        .unlock_lock_type = 0,
        .header_preamble_size = 4,
        .header_size = sizeof(struct smb_hdr),
        .max_header_size = MAX_CIFS_HDR_SIZE,
        .read_rsp_size = sizeof(READ_RSP),
        .lock_cmd = cpu_to_le16(SMB_COM_LOCKING_ANDX),
        .cap_unix = CAP_UNIX,
        .cap_nt_find = CAP_NT_SMBS | CAP_NT_FIND,
        .cap_large_files = CAP_LARGE_FILES,
        .signing_enabled = SECMODE_SIGN_ENABLED,
        .signing_required = SECMODE_SIGN_REQUIRED,
};