// SPDX-License-Identifier: GPL-2.0-only
/*
 *  SMB1 (CIFS) version specific operations
 *
 *  Copyright (c) 2012, Jeff Layton <jlayton@redhat.com>
 */

#include <linux/pagemap.h>
#include <linux/vfs.h>
#include <linux/fs_struct.h>
#include <uapi/linux/magic.h>
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_unicode.h"
#include "fs_context.h"
#include "nterr.h"
#include "smberr.h"
#include "reparse.h"

void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
                          struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
{
        /*
         * If we are reconnecting then should we check to see if
         * any requested capabilities changed locally e.g. via
         * remount but we can not do much about it here
         * if they have (even if we could detect it by the following)
         * Perhaps we could add a backpointer to array of sb from tcon
         * or if we change to make all sb to same share the same
         * sb as NFS - then we only have one backpointer to sb.
         * What if we wanted to mount the server share twice once with
         * and once without posixacls or posix paths?
         */
        __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);

        if (ctx && ctx->no_linux_ext) {
                tcon->fsUnixInfo.Capability = 0;
                tcon->unix_ext = 0; /* Unix Extensions disabled */
                cifs_dbg(FYI, "Linux protocol extensions disabled\n");
                return;
        } else if (ctx)
                tcon->unix_ext = 1; /* Unix Extensions supported */

        if (!tcon->unix_ext) {
                cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
                return;
        }

        if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
                __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
                unsigned int sbflags;

                cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
                /*
                 * check for reconnect case in which we do not
                 * want to change the mount behavior if we can avoid it
                 */
                if (ctx == NULL) {
                        /*
                         * turn off POSIX ACL and PATHNAMES if not set
                         * originally at mount time
                         */
                        if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
                                cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
                        if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
                                if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
                                        cifs_dbg(VFS, "POSIXPATH support change\n");
                                cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
                        } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
                                cifs_dbg(VFS, "possible reconnect error\n");
                                cifs_dbg(VFS, "server disabled POSIX path support\n");
                        }
                }

                if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
                        cifs_dbg(VFS, "per-share encryption not supported yet\n");

                if (cifs_sb)
                        sbflags = cifs_sb_flags(cifs_sb);

                cap &= CIFS_UNIX_CAP_MASK;
                if (ctx && ctx->no_psx_acl)
                        cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
                else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
                        cifs_dbg(FYI, "negotiated posix acl support\n");
                        if (cifs_sb)
                                sbflags |= CIFS_MOUNT_POSIXACL;
                }

                if (ctx && ctx->posix_paths == 0)
                        cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
                else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
                        cifs_dbg(FYI, "negotiate posix pathnames\n");
                        if (cifs_sb)
                                sbflags |= CIFS_MOUNT_POSIX_PATHS;
                }

                if (cifs_sb)
                        atomic_set(&cifs_sb->mnt_cifs_flags, sbflags);

                cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
#ifdef CONFIG_CIFS_DEBUG2
                if (cap & CIFS_UNIX_FCNTL_CAP)
                        cifs_dbg(FYI, "FCNTL cap\n");
                if (cap & CIFS_UNIX_EXTATTR_CAP)
                        cifs_dbg(FYI, "EXTATTR cap\n");
                if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
                        cifs_dbg(FYI, "POSIX path cap\n");
                if (cap & CIFS_UNIX_XATTR_CAP)
                        cifs_dbg(FYI, "XATTR cap\n");
                if (cap & CIFS_UNIX_POSIX_ACL_CAP)
                        cifs_dbg(FYI, "POSIX ACL cap\n");
                if (cap & CIFS_UNIX_LARGE_READ_CAP)
                        cifs_dbg(FYI, "very large read cap\n");
                if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
                        cifs_dbg(FYI, "very large write cap\n");
                if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
                        cifs_dbg(FYI, "transport encryption cap\n");
                if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
                        cifs_dbg(FYI, "mandatory transport encryption cap\n");
#endif /* CIFS_DEBUG2 */
                if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
                        if (ctx == NULL)
                                cifs_dbg(FYI, "resetting capabilities failed\n");
                        else
                                cifs_dbg(VFS, "Negotiating Unix capabilities with the server failed. Consider mounting with the Unix Extensions disabled if problems are found by specifying the nounix mount option.\n");

                }
        }
}

/*
 * 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 cifs_ses *ses, struct TCP_Server_Info *server,
               struct smb_rqst *rqst, struct mid_q_entry *mid,
               unsigned int xid)
{
        struct smb_hdr *in_buf = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
        struct kvec iov[1];
        struct smb_rqst crqst = { .rq_iov = iov, .rq_nvec = 1 };
        int rc = 0;

        /* +2 for BCC field */
        in_buf->Command = SMB_COM_NT_CANCEL;
        in_buf->WordCount = 0;
        put_bcc(0, in_buf);

        iov[0].iov_base = in_buf;
        iov[0].iov_len  = sizeof(struct smb_hdr) + 2;

        cifs_server_lock(server);
        rc = cifs_sign_rqst(&crqst, server, &mid->sequence_number);
        if (rc) {
                cifs_server_unlock(server);
                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_rqst(server, 1, &crqst);
        if (rc < 0)
                server->sequence_number--;

        cifs_server_unlock(server);

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

        return rc;
}

/*
 * Send a LOCKINGX_CANCEL_LOCK to cause the Windows blocking lock to
 * return.
 */
static int
send_lock_cancel(struct cifs_ses *ses, struct TCP_Server_Info *server,
                 struct smb_rqst *rqst, struct mid_q_entry *mid,
                 unsigned int xid)
{
        struct smb_hdr *in_buf = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
        unsigned int in_len = rqst->rq_iov[0].iov_len;
        LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
        int rc;

        /* We just modify the current in_buf to change
         * the type of lock from LOCKING_ANDX_SHARED_LOCK
         * or LOCKING_ANDX_EXCLUSIVE_LOCK to
         * LOCKING_ANDX_CANCEL_LOCK.
         */
        pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
        pSMB->Timeout = 0;
        pSMB->hdr.Mid = get_next_mid(ses->server);

        rc = SendReceive(xid, ses, in_buf, in_len, NULL, NULL, 0);
        if (rc == -ENOLCK)
                rc = 0; /* If we get back -ENOLCK, it probably means we managed
                         * to cancel the lock command before it took effect.
                         */
        return rc;
}

static int cifs_send_cancel(struct cifs_ses *ses, struct TCP_Server_Info *server,
                            struct smb_rqst *rqst, struct mid_q_entry *mid,
                            unsigned int xid)
{
        if (mid->sr_flags & CIFS_WINDOWS_LOCK)
                return send_lock_cancel(ses, server, rqst, mid, xid);
        return send_nt_cancel(ses, server, rqst, mid, xid);
}

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(&server->mid_queue_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) {
                        smb_get_mid(mid);
                        spin_unlock(&server->mid_queue_lock);
                        return mid;
                }
        }
        spin_unlock(&server->mid_queue_lock);
        return NULL;
}

static void
cifs_add_credits(struct TCP_Server_Info *server,
                 struct cifs_credits *credits, const int optype)
{
        spin_lock(&server->req_lock);
        server->credits += credits->value;
        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, reconnect = false;

        spin_lock(&server->mid_counter_lock);
        /* mid is 16 bit only for CIFS/SMB */
        cur_mid = (__u16)((server->current_mid) & 0xffff);
        /* we do not want to loop forever */
        last_mid = cur_mid;
        cur_mid++;
        /* avoid 0xFFFF MID */
        if (cur_mid == 0xffff)
                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;
                spin_lock(&server->mid_queue_lock);
                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;
                        }
                }
                spin_unlock(&server->mid_queue_lock);

                /*
                 * 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)
                        reconnect = true;

                if (!collision) {
                        mid = (__u64)cur_mid;
                        server->current_mid = mid;
                        break;
                }
                cur_mid++;
        }
        spin_unlock(&server->mid_counter_lock);

        if (reconnect) {
                cifs_signal_cifsd_for_reconnect(server, false);
        }

        return mid;
}

static void
cifs_downgrade_oplock(struct TCP_Server_Info *server,
                      struct cifsInodeInfo *cinode, __u32 oplock,
                      __u16 epoch, bool *purge_cache)
{
        lockdep_assert_held(&cinode->open_file_lock);
        cifs_set_oplock_level(cinode, oplock);
}

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,
               struct TCP_Server_Info *server)
{
        int rc;
        rc = CIFSSMBNegotiate(xid, ses, server);
        return rc;
}

static unsigned int
smb1_negotiate_wsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        __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 (ctx->got_wsize)
                wsize = ctx->vol_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));

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

        return wsize;
}

static unsigned int
smb1_negotiate_rsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        __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 = ctx->got_rsize ? ctx->vol_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,
              struct cifs_sb_info *cifs_sb)
{
        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_obj(FILE_ALL_INFO);
        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,
                                struct cifs_open_info_data *data)
{
        int rc = -EOPNOTSUPP;
        FILE_ALL_INFO fi = {};
        struct cifs_search_info search_info = {};
        bool non_unicode_wildcard = false;

        data->reparse_point = false;
        data->adjust_tz = false;

        /*
         * First try CIFSSMBQPathInfo() function which returns more info
         * (NumberOfLinks) than CIFSFindFirst() fallback function.
         * Some servers like Win9x do not support SMB_QUERY_FILE_ALL_INFO over
         * TRANS2_QUERY_PATH_INFORMATION, but supports it with filehandle over
         * TRANS2_QUERY_FILE_INFORMATION (function CIFSSMBQFileInfo(). But SMB
         * Open command on non-NT servers works only for files, does not work
         * for directories. And moreover Win9x SMB server returns bogus data in
         * SMB_QUERY_FILE_ALL_INFO Attributes field. So for non-NT servers,
         * do not even use CIFSSMBQPathInfo() or CIFSSMBQFileInfo() function.
         */
        if (tcon->ses->capabilities & CAP_NT_SMBS)
                rc = CIFSSMBQPathInfo(xid, tcon, full_path, &fi, 0 /* not legacy */,
                                      cifs_sb->local_nls, cifs_remap(cifs_sb));

        /*
         * Non-UNICODE variant of fallback functions below expands wildcards,
         * so they cannot be used for querying paths with wildcard characters.
         */
        if (rc && !(tcon->ses->capabilities & CAP_UNICODE) && strpbrk(full_path, "*?\"><"))
                non_unicode_wildcard = true;

        /*
         * Then fallback to CIFSFindFirst() which works also with non-NT servers
         * but does not does not provide NumberOfLinks.
         */
        if ((rc == -EOPNOTSUPP || rc == -EINVAL) &&
            !non_unicode_wildcard) {
                if (!(tcon->ses->capabilities & tcon->ses->server->vals->cap_nt_find))
                        search_info.info_level = SMB_FIND_FILE_INFO_STANDARD;
                else
                        search_info.info_level = SMB_FIND_FILE_FULL_DIRECTORY_INFO;
                rc = CIFSFindFirst(xid, tcon, full_path, cifs_sb, NULL,
                                   CIFS_SEARCH_CLOSE_ALWAYS | CIFS_SEARCH_CLOSE_AT_END,
                                   &search_info, false);
                if (rc == 0) {
                        if (!(tcon->ses->capabilities & tcon->ses->server->vals->cap_nt_find)) {
                                FIND_FILE_STANDARD_INFO *di;
                                int offset = tcon->ses->server->timeAdj;

                                di = (FIND_FILE_STANDARD_INFO *)search_info.srch_entries_start;
                                fi.CreationTime = cpu_to_le64(cifs_UnixTimeToNT(cnvrtDosUnixTm(
                                                di->CreationDate, di->CreationTime, offset)));
                                fi.LastAccessTime = cpu_to_le64(cifs_UnixTimeToNT(cnvrtDosUnixTm(
                                                di->LastAccessDate, di->LastAccessTime, offset)));
                                fi.LastWriteTime = cpu_to_le64(cifs_UnixTimeToNT(cnvrtDosUnixTm(
                                                di->LastWriteDate, di->LastWriteTime, offset)));
                                fi.ChangeTime = fi.LastWriteTime;
                                fi.Attributes = cpu_to_le32(le16_to_cpu(di->Attributes));
                                fi.AllocationSize = cpu_to_le64(le32_to_cpu(di->AllocationSize));
                                fi.EndOfFile = cpu_to_le64(le32_to_cpu(di->DataSize));
                        } else {
                                FILE_FULL_DIRECTORY_INFO *di;

                                di = (FILE_FULL_DIRECTORY_INFO *)search_info.srch_entries_start;
                                fi.CreationTime = di->CreationTime;
                                fi.LastAccessTime = di->LastAccessTime;
                                fi.LastWriteTime = di->LastWriteTime;
                                fi.ChangeTime = di->ChangeTime;
                                fi.Attributes = di->ExtFileAttributes;
                                fi.AllocationSize = di->AllocationSize;
                                fi.EndOfFile = di->EndOfFile;
                                fi.EASize = di->EaSize;
                        }
                        fi.NumberOfLinks = cpu_to_le32(1);
                        fi.DeletePending = 0;
                        fi.Directory = !!(le32_to_cpu(fi.Attributes) & ATTR_DIRECTORY);
                        cifs_buf_release(search_info.ntwrk_buf_start);
                } else if (!full_path[0]) {
                        /*
                         * CIFSFindFirst() does not work on root path if the
                         * root path was exported on the server from the top
                         * level path (drive letter).
                         */
                        rc = -EOPNOTSUPP;
                }
        }

        /*
         * If everything failed then fallback to the legacy SMB command
         * SMB_COM_QUERY_INFORMATION which works with all servers, but
         * provide just few information.
         */
        if ((rc == -EOPNOTSUPP || rc == -EINVAL) && !non_unicode_wildcard) {
                rc = SMBQueryInformation(xid, tcon, full_path, &fi, cifs_sb->local_nls,
                                         cifs_remap(cifs_sb));
                data->adjust_tz = true;
        } else if ((rc == -EOPNOTSUPP || rc == -EINVAL) && non_unicode_wildcard) {
                /* Path with non-UNICODE wildcard character cannot exist. */
                rc = -ENOENT;
        }

        if (!rc) {
                move_cifs_info_to_smb2(&data->fi, &fi);
                data->reparse_point = le32_to_cpu(fi.Attributes) & ATTR_REPARSE_POINT;
        }

#ifdef CONFIG_CIFS_XATTR
        /*
         * For non-symlink WSL reparse points it is required to fetch
         * EA $LXMOD which contains in its S_DT part the mandatory file type.
         */
        if (!rc && data->reparse_point) {
                struct smb2_file_full_ea_info *ea;
                u32 next = 0;

                ea = (struct smb2_file_full_ea_info *)data->wsl.eas;
                do {
                        ea = (void *)((u8 *)ea + next);
                        next = le32_to_cpu(ea->next_entry_offset);
                } while (next);
                if (le16_to_cpu(ea->ea_value_length)) {
                        ea->next_entry_offset = cpu_to_le32(ALIGN(sizeof(*ea) +
                                                ea->ea_name_length + 1 +
                                                le16_to_cpu(ea->ea_value_length), 4));
                        ea = (void *)((u8 *)ea + le32_to_cpu(ea->next_entry_offset));
                }

                rc = CIFSSMBQAllEAs(xid, tcon, full_path, SMB2_WSL_XATTR_MODE,
                                    &ea->ea_data[SMB2_WSL_XATTR_NAME_LEN + 1],
                                    SMB2_WSL_XATTR_MODE_SIZE, cifs_sb);
                if (rc == SMB2_WSL_XATTR_MODE_SIZE) {
                        ea->next_entry_offset = cpu_to_le32(0);
                        ea->flags = 0;
                        ea->ea_name_length = SMB2_WSL_XATTR_NAME_LEN;
                        ea->ea_value_length = cpu_to_le16(SMB2_WSL_XATTR_MODE_SIZE);
                        memcpy(&ea->ea_data[0], SMB2_WSL_XATTR_MODE, SMB2_WSL_XATTR_NAME_LEN + 1);
                        data->wsl.eas_len += ALIGN(sizeof(*ea) + SMB2_WSL_XATTR_NAME_LEN + 1 +
                                                   SMB2_WSL_XATTR_MODE_SIZE, 4);
                        rc = 0;
                } else if (rc >= 0) {
                        /* It is an error if EA $LXMOD has wrong size. */
                        rc = -EINVAL;
                } else {
                        /*
                         * In all other cases ignore error if fetching
                         * of EA $LXMOD failed. It is needed only for
                         * non-symlink WSL reparse points and wsl_to_fattr()
                         * handle the case when EA is missing.
                         */
                        rc = 0;
                }
        }

        /*
         * For WSL CHR and BLK reparse points it is required to fetch
         * EA $LXDEV which contains major and minor device numbers.
         */
        if (!rc && data->reparse_point) {
                struct smb2_file_full_ea_info *ea;
                u32 next = 0;

                ea = (struct smb2_file_full_ea_info *)data->wsl.eas;
                do {
                        ea = (void *)((u8 *)ea + next);
                        next = le32_to_cpu(ea->next_entry_offset);
                } while (next);
                if (le16_to_cpu(ea->ea_value_length)) {
                        ea->next_entry_offset = cpu_to_le32(ALIGN(sizeof(*ea) +
                                                ea->ea_name_length + 1 +
                                                le16_to_cpu(ea->ea_value_length), 4));
                        ea = (void *)((u8 *)ea + le32_to_cpu(ea->next_entry_offset));
                }

                rc = CIFSSMBQAllEAs(xid, tcon, full_path, SMB2_WSL_XATTR_DEV,
                                    &ea->ea_data[SMB2_WSL_XATTR_NAME_LEN + 1],
                                    SMB2_WSL_XATTR_DEV_SIZE, cifs_sb);
                if (rc == SMB2_WSL_XATTR_DEV_SIZE) {
                        ea->next_entry_offset = cpu_to_le32(0);
                        ea->flags = 0;
                        ea->ea_name_length = SMB2_WSL_XATTR_NAME_LEN;
                        ea->ea_value_length = cpu_to_le16(SMB2_WSL_XATTR_DEV_SIZE);
                        memcpy(&ea->ea_data[0], SMB2_WSL_XATTR_DEV, SMB2_WSL_XATTR_NAME_LEN + 1);
                        data->wsl.eas_len += ALIGN(sizeof(*ea) + SMB2_WSL_XATTR_NAME_LEN + 1 +
                                                   SMB2_WSL_XATTR_MODE_SIZE, 4);
                        rc = 0;
                } else if (rc >= 0) {
                        /* It is an error if EA $LXDEV has wrong size. */
                        rc = -EINVAL;
                } else {
                        /*
                         * In all other cases ignore error if fetching
                         * of EA $LXDEV failed. It is needed only for
                         * WSL CHR and BLK reparse points and wsl_to_fattr()
                         * handle the case when EA is missing.
                         */
                        rc = 0;
                }
        }
#endif

        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, struct cifs_open_info_data *unused)
{
        /*
         * 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?
         *
         * CIFSGetSrvInodeNumber() uses SMB_QUERY_FILE_INTERNAL_INFO
         * which is SMB PASSTHROUGH level therefore check for capability.
         * Note that this function can be called with tcon == NULL.
         */
        if (tcon && !(tcon->ses->capabilities & CAP_INFOLEVEL_PASSTHRU))
                return -EOPNOTSUPP;
        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 cifsFileInfo *cfile, struct cifs_open_info_data *data)
{
        int rc;
        FILE_ALL_INFO fi = {};

        /*
         * CIFSSMBQFileInfo() for non-NT servers returns bogus data in
         * Attributes fields. So do not use this command for non-NT servers.
         */
        if (!(tcon->ses->capabilities & CAP_NT_SMBS))
                return -EOPNOTSUPP;

        if (cfile->symlink_target) {
                data->symlink_target = kstrdup(cfile->symlink_target, GFP_KERNEL);
                if (!data->symlink_target)
                        return -ENOMEM;
        }

        rc = CIFSSMBQFileInfo(xid, tcon, cfile->fid.netfid, &fi);
        if (!rc)
                move_cifs_info_to_smb2(&data->fi, &fi);
        return rc;
}

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_sb);
        if (rc == -EOPNOTSUPP || rc == -EINVAL)
                rc = SMBSetInformation(xid, tcon, full_path,
                                       info.Attributes,
                                       0 /* do not change write time */,
                                       cifs_sb->local_nls, cifs_sb);
        if (rc == 0)
                cifsInode->cifsAttrs = dosattrs;
}

static int cifs_open_file(const unsigned int xid, struct cifs_open_parms *oparms, __u32 *oplock,
                          void *buf)
{
        struct cifs_open_info_data *data = buf;
        FILE_ALL_INFO fi = {};
        int rc;

        if (!(oparms->tcon->ses->capabilities & CAP_NT_SMBS))
                rc = SMBLegacyOpen(xid, oparms->tcon, oparms->path,
                                   oparms->disposition,
                                   oparms->desired_access,
                                   oparms->create_options,
                                   &oparms->fid->netfid, oplock, &fi,
                                   oparms->cifs_sb->local_nls,
                                   cifs_remap(oparms->cifs_sb));
        else
                rc = CIFS_open(xid, oparms, oplock, &fi);

        if (!rc && data)
                move_cifs_info_to_smb2(&data->fi, &fi);

        return rc;
}

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

        lockdep_assert_held(&cinode->open_file_lock);

        cfile->fid.netfid = fid->netfid;
        cifs_set_oplock_level(cinode, oplock);
        cinode->can_cache_brlcks = CIFS_CACHE_WRITE(cinode);
}

static int
cifs_close_file(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifs_fid *fid)
{
        return 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;
        FILE_BASIC_INFO new_buf;
        struct cifs_open_info_data query_data;
        __le64 write_time = buf->LastWriteTime;
        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, FIND_FSUID_ONLY);

        if (open_file) {
                fid.netfid = open_file->fid.netfid;
                netpid = open_file->pid;
                tcon = tlink_tcon(open_file->tlink);
        } else {
                tlink = cifs_sb_tlink(cifs_sb);
                if (IS_ERR(tlink)) {
                        rc = PTR_ERR(tlink);
                        tlink = NULL;
                        goto out;
                }
                tcon = tlink_tcon(tlink);
        }

        /*
         * Non-NT servers interprets zero time value in SMB_SET_FILE_BASIC_INFO
         * over TRANS2_SET_FILE_INFORMATION as a valid time value. NT servers
         * interprets zero time value as do not change existing value on server.
         * API of ->set_file_info() callback expects that zero time value has
         * the NT meaning - do not change. Therefore if server is non-NT and
         * some time values in "buf" are zero, then fetch missing time values.
         */
        if (!(tcon->ses->capabilities & CAP_NT_SMBS) &&
            (!buf->CreationTime || !buf->LastAccessTime ||
             !buf->LastWriteTime || !buf->ChangeTime)) {
                rc = cifs_query_path_info(xid, tcon, cifs_sb, full_path, &query_data);
                if (rc) {
                        if (open_file) {
                                cifsFileInfo_put(open_file);
                                open_file = NULL;
                        }
                        goto out;
                }
                /*
                 * Original write_time from buf->LastWriteTime is preserved
                 * as SMBSetInformation() interprets zero as do not change.
                 */
                new_buf = *buf;
                buf = &new_buf;
                if (!buf->CreationTime)
                        buf->CreationTime = query_data.fi.CreationTime;
                if (!buf->LastAccessTime)
                        buf->LastAccessTime = query_data.fi.LastAccessTime;
                if (!buf->LastWriteTime)
                        buf->LastWriteTime = query_data.fi.LastWriteTime;
                if (!buf->ChangeTime)
                        buf->ChangeTime = query_data.fi.ChangeTime;
        }

        if (open_file)
                goto set_via_filehandle;

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

        oparms = (struct cifs_open_parms) {
                .tcon = tcon,
                .cifs_sb = cifs_sb,
                .desired_access = SYNCHRONIZE | FILE_WRITE_ATTRIBUTES,
                .create_options = cifs_create_options(cifs_sb, 0),
                .disposition = FILE_OPEN,
                .path = full_path,
                .fid = &fid,
        };

        if (S_ISDIR(inode->i_mode) && !(tcon->ses->capabilities & CAP_NT_SMBS)) {
                /* Opening directory path is not possible on non-NT servers. */
                rc = -EOPNOTSUPP;
        } else {
                /*
                 * Use cifs_open_file() instead of CIFS_open() as the
                 * cifs_open_file() selects the correct function which
                 * works also on non-NT servers.
                 */
                rc = cifs_open_file(xid, &oparms, &oplock, NULL);
                /*
                 * Opening path for writing on non-NT servers is not
                 * possible when the read-only attribute is already set.
                 * Non-NT server in this case returns -EACCES. For those
                 * servers the only possible way how to clear the read-only
                 * bit is via SMB_COM_SETATTR command.
                 */
                if (rc == -EACCES &&
                    (cinode->cifsAttrs & ATTR_READONLY) &&
                     le32_to_cpu(buf->Attributes) != 0 && /* 0 = do not change attrs */
                     !(le32_to_cpu(buf->Attributes) & ATTR_READONLY) &&
                     !(tcon->ses->capabilities & CAP_NT_SMBS))
                        rc = -EOPNOTSUPP;
        }

        /* Fallback to SMB_COM_SETATTR command when absolutely needed. */
        if (rc == -EOPNOTSUPP) {
                cifs_dbg(FYI, "calling SetInformation since SetPathInfo for attrs/times not supported by this server\n");
                rc = SMBSetInformation(xid, tcon, full_path,
                                       buf->Attributes != 0 ? buf->Attributes : cpu_to_le32(cinode->cifsAttrs),
                                       write_time,
                                       cifs_sb->local_nls, cifs_sb);
                if (rc == 0)
                        cinode->cifsAttrs = le32_to_cpu(buf->Attributes);
                else
                        rc = -EACCES;
                goto out;
        }

        if (rc != 0) {
                if (rc == -EIO)
                        rc = -EINVAL;
                goto out;
        }

        netpid = current->tgid;
        cifs_dbg(FYI, "calling SetFileInfo since SetPathInfo for attrs/times not supported by this server\n");

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);

        /*
        * Setting the read-only bit is not honored on non-NT servers when done
         * via open-semantics. So for setting it, use SMB_COM_SETATTR command.
         * This command works only after the file is closed, so use it only when
         * operation was called without the filehandle.
         */
        if (open_file == NULL &&
            !(tcon->ses->capabilities & CAP_NT_SMBS) &&
            le32_to_cpu(buf->Attributes) & ATTR_READONLY) {
                SMBSetInformation(xid, tcon, full_path,
                                  buf->Attributes,
                                  0 /* do not change write time */,
                                  cifs_sb->local_nls, cifs_sb);
        }
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, __u64 persistent_fid,
                                __u64 volatile_fid, __u16 net_fid,
                                struct cifsInodeInfo *cinode, unsigned int oplock)
{
        unsigned int sbflags = cifs_sb_flags(CIFS_SB(cinode));
        __u8 op;

        op = !!((oplock & CIFS_CACHE_READ_FLG) || (sbflags & CIFS_MOUNT_RO_CACHE));
        return CIFSSMBLock(0, tcon, net_fid, current->tgid, 0, 0, 0, 0,
                           LOCKING_ANDX_OPLOCK_RELEASE, false, op);
}

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

        buf->f_type = CIFS_SUPER_MAGIC;

        /*
         * 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;
        struct dfs_info3_param referral = {0};

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

        if (!rc) {
                *symlinkinfo = kstrdup(referral.node_name, GFP_KERNEL);
                free_dfs_info_param(&referral);
                if (!*symlinkinfo)
                        rc = -ENOMEM;
        }
        return rc;
#else /* No DFS support */
        return -EREMOTE;
#endif
}

static int cifs_query_symlink(const unsigned int xid,
                              struct cifs_tcon *tcon,
                              struct cifs_sb_info *cifs_sb,
                              const char *full_path,
                              char **target_path)
{
        int rc;

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

        if (!cap_unix(tcon->ses))
                return -EOPNOTSUPP;

        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);
        return rc;
}

static struct reparse_data_buffer *cifs_get_reparse_point_buffer(const struct kvec *rsp_iov,
                                                                 u32 *plen)
{
        TRANSACT_IOCTL_RSP *io = rsp_iov->iov_base;
        *plen = le16_to_cpu(io->ByteCount);
        return (struct reparse_data_buffer *)((__u8 *)&io->hdr.Protocol +
                                              le32_to_cpu(io->DataOffset));
}

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)->ctx->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;
}

static int
cifs_make_node(unsigned int xid, struct inode *inode,
               struct dentry *dentry, struct cifs_tcon *tcon,
               const char *full_path, umode_t mode, dev_t dev)
{
        struct cifs_sb_info *cifs_sb = CIFS_SB(inode);
        unsigned int sbflags = cifs_sb_flags(cifs_sb);
        struct inode *newinode = NULL;
        int rc;

        if (tcon->unix_ext) {
                /*
                 * SMB1 Unix Extensions: requires server support but
                 * works with all special files
                 */
                struct cifs_unix_set_info_args args = {
                        .mode   = mode & ~current_umask(),
                        .ctime  = NO_CHANGE_64,
                        .atime  = NO_CHANGE_64,
                        .mtime  = NO_CHANGE_64,
                        .device = dev,
                };
                if (sbflags & CIFS_MOUNT_SET_UID) {
                        args.uid = current_fsuid();
                        args.gid = current_fsgid();
                } else {
                        args.uid = INVALID_UID; /* no change */
                        args.gid = INVALID_GID; /* no change */
                }
                rc = CIFSSMBUnixSetPathInfo(xid, tcon, full_path, &args,
                                            cifs_sb->local_nls,
                                            cifs_remap(cifs_sb));
                if (rc)
                        return rc;

                rc = cifs_get_inode_info_unix(&newinode, full_path,
                                              inode->i_sb, xid);

                if (rc == 0)
                        d_instantiate(dentry, newinode);
                return rc;
        } else if (sbflags & CIFS_MOUNT_UNX_EMUL) {
                /*
                 * Check if mounted with mount parm 'sfu' mount parm.
                 * SFU emulation should work with all servers
                 * and was used by default in earlier versions of Windows.
                 */
                return cifs_sfu_make_node(xid, inode, dentry, tcon,
                                          full_path, mode, dev);
        } else if (CIFS_REPARSE_SUPPORT(tcon)) {
                /*
                 * mknod via reparse points requires server support for
                 * storing reparse points, which is available since
                 * Windows 2000, but was not widely used until release
                 * of Windows Server 2012 by the Windows NFS server.
                 */
                return mknod_reparse(xid, inode, dentry, tcon,
                                     full_path, mode, dev);
        } else {
                return -EOPNOTSUPP;
        }
}

static bool
cifs_is_network_name_deleted(char *buf, struct TCP_Server_Info *server)
{
        struct smb_hdr *shdr = (struct smb_hdr *)buf;
        struct TCP_Server_Info *pserver;
        struct cifs_ses *ses;
        struct cifs_tcon *tcon;

        if (shdr->Flags2 & SMBFLG2_ERR_STATUS) {
                if (shdr->Status.CifsError != cpu_to_le32(NT_STATUS_NETWORK_NAME_DELETED))
                        return false;
        } else {
                if (shdr->Status.DosError.ErrorClass != ERRSRV ||
                    shdr->Status.DosError.Error != cpu_to_le16(ERRinvtid))
                        return false;
        }

        /* If server is a channel, select the primary channel */
        pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;

        spin_lock(&cifs_tcp_ses_lock);
        list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
                if (cifs_ses_exiting(ses))
                        continue;
                list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
                        if (tcon->tid == shdr->Tid) {
                                spin_lock(&tcon->tc_lock);
                                tcon->need_reconnect = true;
                                spin_unlock(&tcon->tc_lock);
                                spin_unlock(&cifs_tcp_ses_lock);
                                pr_warn_once("Server share %s deleted.\n",
                                             tcon->tree_name);
                                return true;
                        }
                }
        }
        spin_unlock(&cifs_tcp_ses_lock);

        return false;
}

struct smb_version_operations smb1_operations = {
        .send_cancel = cifs_send_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 = smb1_negotiate_wsize,
        .negotiate_rsize = smb1_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_reparse_point = cifs_query_reparse_point,
        .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,
        .get_reparse_point_buffer = cifs_get_reparse_point_buffer,
        .create_reparse_inode = cifs_create_reparse_inode,
        .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 */
        .get_acl = get_cifs_acl,
        .get_acl_by_fid = get_cifs_acl_by_fid,
        .set_acl = set_cifs_acl,
        .make_node = cifs_make_node,
        .is_network_name_deleted = cifs_is_network_name_deleted,
};

struct smb_version_values smb1_values = {
        .version_string = SMB1_VERSION_STRING,
        .protocol_id = SMB10_PROT_ID,
        .large_lock_type = LOCKING_ANDX_LARGE_FILES,
        .exclusive_lock_type = 0,
        .shared_lock_type = LOCKING_ANDX_SHARED_LOCK,
        .unlock_lock_type = 0,
        .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,
        .cap_unicode = CAP_UNICODE,
        .signing_enabled = SECMODE_SIGN_ENABLED,
        .signing_required = SECMODE_SIGN_REQUIRED,
};