// SPDX-License-Identifier: GPL-2.0
/*
 *  SMB2 version specific operations
 *
 *  Copyright (c) 2012, Jeff Layton <jlayton@redhat.com>
 */

#include <linux/pagemap.h>
#include <linux/vfs.h>
#include <linux/falloc.h>
#include <linux/scatterlist.h>
#include <linux/uuid.h>
#include <linux/sort.h>
#include <crypto/aead.h>
#include <linux/fiemap.h>
#include "cifsfs.h"
#include "cifsglob.h"
#include "smb2pdu.h"
#include "smb2proto.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_unicode.h"
#include "smb2status.h"
#include "smb2glob.h"
#include "cifs_ioctl.h"
#include "smbdirect.h"
#include "fs_context.h"

/* Change credits for different ops and return the total number of credits */
static int
change_conf(struct TCP_Server_Info *server)
{
        server->credits += server->echo_credits + server->oplock_credits;
        server->oplock_credits = server->echo_credits = 0;
        switch (server->credits) {
        case 0:
                return 0;
        case 1:
                server->echoes = false;
                server->oplocks = false;
                break;
        case 2:
                server->echoes = true;
                server->oplocks = false;
                server->echo_credits = 1;
                break;
        default:
                server->echoes = true;
                if (enable_oplocks) {
                        server->oplocks = true;
                        server->oplock_credits = 1;
                } else
                        server->oplocks = false;

                server->echo_credits = 1;
        }
        server->credits -= server->echo_credits + server->oplock_credits;
        return server->credits + server->echo_credits + server->oplock_credits;
}

static void
smb2_add_credits(struct TCP_Server_Info *server,
                 const struct cifs_credits *credits, const int optype)
{
        int *val, rc = -1;
        int scredits, in_flight;
        unsigned int add = credits->value;
        unsigned int instance = credits->instance;
        bool reconnect_detected = false;
        bool reconnect_with_invalid_credits = false;

        spin_lock(&server->req_lock);
        val = server->ops->get_credits_field(server, optype);

        /* eg found case where write overlapping reconnect messed up credits */
        if (((optype & CIFS_OP_MASK) == CIFS_NEG_OP) && (*val != 0))
                reconnect_with_invalid_credits = true;

        if ((instance == 0) || (instance == server->reconnect_instance))
                *val += add;
        else
                reconnect_detected = true;

        if (*val > 65000) {
                *val = 65000; /* Don't get near 64K credits, avoid srv bugs */
                pr_warn_once("server overflowed SMB3 credits\n");
        }
        server->in_flight--;
        if (server->in_flight == 0 &&
           ((optype & CIFS_OP_MASK) != CIFS_NEG_OP) &&
           ((optype & CIFS_OP_MASK) != CIFS_SESS_OP))
                rc = change_conf(server);
        /*
         * Sometimes server returns 0 credits on oplock break ack - we need to
         * rebalance credits in this case.
         */
        else if (server->in_flight > 0 && server->oplock_credits == 0 &&
                 server->oplocks) {
                if (server->credits > 1) {
                        server->credits--;
                        server->oplock_credits++;
                }
        }
        scredits = *val;
        in_flight = server->in_flight;
        spin_unlock(&server->req_lock);
        wake_up(&server->request_q);

        if (reconnect_detected) {
                trace_smb3_reconnect_detected(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, add, in_flight);

                cifs_dbg(FYI, "trying to put %d credits from the old server instance %d\n",
                         add, instance);
        }

        if (reconnect_with_invalid_credits) {
                trace_smb3_reconnect_with_invalid_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, add, in_flight);
                cifs_dbg(FYI, "Negotiate operation when server credits is non-zero. Optype: %d, server credits: %d, credits added: %d\n",
                         optype, scredits, add);
        }

        if (server->tcpStatus == CifsNeedReconnect
            || server->tcpStatus == CifsExiting)
                return;

        switch (rc) {
        case -1:
                /* change_conf hasn't been executed */
                break;
        case 0:
                cifs_server_dbg(VFS, "Possible client or server bug - zero credits\n");
                break;
        case 1:
                cifs_server_dbg(VFS, "disabling echoes and oplocks\n");
                break;
        case 2:
                cifs_dbg(FYI, "disabling oplocks\n");
                break;
        default:
                /* change_conf rebalanced credits for different types */
                break;
        }

        trace_smb3_add_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, add, in_flight);
        cifs_dbg(FYI, "%s: added %u credits total=%d\n", __func__, add, scredits);
}

static void
smb2_set_credits(struct TCP_Server_Info *server, const int val)
{
        int scredits, in_flight;

        spin_lock(&server->req_lock);
        server->credits = val;
        if (val == 1)
                server->reconnect_instance++;
        scredits = server->credits;
        in_flight = server->in_flight;
        spin_unlock(&server->req_lock);

        trace_smb3_set_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, val, in_flight);
        cifs_dbg(FYI, "%s: set %u credits\n", __func__, val);

        /* don't log while holding the lock */
        if (val == 1)
                cifs_dbg(FYI, "set credits to 1 due to smb2 reconnect\n");
}

static int *
smb2_get_credits_field(struct TCP_Server_Info *server, const int optype)
{
        switch (optype) {
        case CIFS_ECHO_OP:
                return &server->echo_credits;
        case CIFS_OBREAK_OP:
                return &server->oplock_credits;
        default:
                return &server->credits;
        }
}

static unsigned int
smb2_get_credits(struct mid_q_entry *mid)
{
        return mid->credits_received;
}

static int
smb2_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
                      unsigned int *num, struct cifs_credits *credits)
{
        int rc = 0;
        unsigned int scredits, in_flight;

        spin_lock(&server->req_lock);
        while (1) {
                if (server->credits <= 0) {
                        spin_unlock(&server->req_lock);
                        cifs_num_waiters_inc(server);
                        rc = wait_event_killable(server->request_q,
                                has_credits(server, &server->credits, 1));
                        cifs_num_waiters_dec(server);
                        if (rc)
                                return rc;
                        spin_lock(&server->req_lock);
                } else {
                        if (server->tcpStatus == CifsExiting) {
                                spin_unlock(&server->req_lock);
                                return -ENOENT;
                        }

                        scredits = server->credits;
                        /* can deadlock with reopen */
                        if (scredits <= 8) {
                                *num = SMB2_MAX_BUFFER_SIZE;
                                credits->value = 0;
                                credits->instance = 0;
                                break;
                        }

                        /* leave some credits for reopen and other ops */
                        scredits -= 8;
                        *num = min_t(unsigned int, size,
                                     scredits * SMB2_MAX_BUFFER_SIZE);

                        credits->value =
                                DIV_ROUND_UP(*num, SMB2_MAX_BUFFER_SIZE);
                        credits->instance = server->reconnect_instance;
                        server->credits -= credits->value;
                        server->in_flight++;
                        if (server->in_flight > server->max_in_flight)
                                server->max_in_flight = server->in_flight;
                        break;
                }
        }
        scredits = server->credits;
        in_flight = server->in_flight;
        spin_unlock(&server->req_lock);

        trace_smb3_add_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, -(credits->value), in_flight);
        cifs_dbg(FYI, "%s: removed %u credits total=%d\n",
                        __func__, credits->value, scredits);

        return rc;
}

static int
smb2_adjust_credits(struct TCP_Server_Info *server,
                    struct cifs_credits *credits,
                    const unsigned int payload_size)
{
        int new_val = DIV_ROUND_UP(payload_size, SMB2_MAX_BUFFER_SIZE);
        int scredits, in_flight;

        if (!credits->value || credits->value == new_val)
                return 0;

        if (credits->value < new_val) {
                trace_smb3_too_many_credits(server->CurrentMid,
                                server->conn_id, server->hostname, 0, credits->value - new_val, 0);
                cifs_server_dbg(VFS, "request has less credits (%d) than required (%d)",
                                credits->value, new_val);

                return -ENOTSUPP;
        }

        spin_lock(&server->req_lock);

        if (server->reconnect_instance != credits->instance) {
                scredits = server->credits;
                in_flight = server->in_flight;
                spin_unlock(&server->req_lock);

                trace_smb3_reconnect_detected(server->CurrentMid,
                        server->conn_id, server->hostname, scredits,
                        credits->value - new_val, in_flight);
                cifs_server_dbg(VFS, "trying to return %d credits to old session\n",
                         credits->value - new_val);
                return -EAGAIN;
        }

        server->credits += credits->value - new_val;
        scredits = server->credits;
        in_flight = server->in_flight;
        spin_unlock(&server->req_lock);
        wake_up(&server->request_q);

        trace_smb3_add_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits,
                        credits->value - new_val, in_flight);
        cifs_dbg(FYI, "%s: adjust added %u credits total=%d\n",
                        __func__, credits->value - new_val, scredits);

        credits->value = new_val;

        return 0;
}

static __u64
smb2_get_next_mid(struct TCP_Server_Info *server)
{
        __u64 mid;
        /* for SMB2 we need the current value */
        spin_lock(&GlobalMid_Lock);
        mid = server->CurrentMid++;
        spin_unlock(&GlobalMid_Lock);
        return mid;
}

static void
smb2_revert_current_mid(struct TCP_Server_Info *server, const unsigned int val)
{
        spin_lock(&GlobalMid_Lock);
        if (server->CurrentMid >= val)
                server->CurrentMid -= val;
        spin_unlock(&GlobalMid_Lock);
}

static struct mid_q_entry *
__smb2_find_mid(struct TCP_Server_Info *server, char *buf, bool dequeue)
{
        struct mid_q_entry *mid;
        struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
        __u64 wire_mid = le64_to_cpu(shdr->MessageId);

        if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
                cifs_server_dbg(VFS, "Encrypted frame parsing not supported yet\n");
                return NULL;
        }

        spin_lock(&GlobalMid_Lock);
        list_for_each_entry(mid, &server->pending_mid_q, qhead) {
                if ((mid->mid == wire_mid) &&
                    (mid->mid_state == MID_REQUEST_SUBMITTED) &&
                    (mid->command == shdr->Command)) {
                        kref_get(&mid->refcount);
                        if (dequeue) {
                                list_del_init(&mid->qhead);
                                mid->mid_flags |= MID_DELETED;
                        }
                        spin_unlock(&GlobalMid_Lock);
                        return mid;
                }
        }
        spin_unlock(&GlobalMid_Lock);
        return NULL;
}

static struct mid_q_entry *
smb2_find_mid(struct TCP_Server_Info *server, char *buf)
{
        return __smb2_find_mid(server, buf, false);
}

static struct mid_q_entry *
smb2_find_dequeue_mid(struct TCP_Server_Info *server, char *buf)
{
        return __smb2_find_mid(server, buf, true);
}

static void
smb2_dump_detail(void *buf, struct TCP_Server_Info *server)
{
#ifdef CONFIG_CIFS_DEBUG2
        struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;

        cifs_server_dbg(VFS, "Cmd: %d Err: 0x%x Flags: 0x%x Mid: %llu Pid: %d\n",
                 shdr->Command, shdr->Status, shdr->Flags, shdr->MessageId,
                 shdr->ProcessId);
        cifs_server_dbg(VFS, "smb buf %p len %u\n", buf,
                 server->ops->calc_smb_size(buf, server));
#endif
}

static bool
smb2_need_neg(struct TCP_Server_Info *server)
{
        return server->max_read == 0;
}

static int
smb2_negotiate(const unsigned int xid, struct cifs_ses *ses)
{
        int rc;

        spin_lock(&GlobalMid_Lock);
        cifs_ses_server(ses)->CurrentMid = 0;
        spin_unlock(&GlobalMid_Lock);
        rc = SMB2_negotiate(xid, ses);
        /* BB we probably don't need to retry with modern servers */
        if (rc == -EAGAIN)
                rc = -EHOSTDOWN;
        return rc;
}

static unsigned int
smb2_negotiate_wsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int wsize;

        /* start with specified wsize, or default */
        wsize = ctx->wsize ? ctx->wsize : CIFS_DEFAULT_IOSIZE;
        wsize = min_t(unsigned int, wsize, server->max_write);
        if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
                wsize = min_t(unsigned int, wsize, SMB2_MAX_BUFFER_SIZE);

        return wsize;
}

static unsigned int
smb3_negotiate_wsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int wsize;

        /* start with specified wsize, or default */
        wsize = ctx->wsize ? ctx->wsize : SMB3_DEFAULT_IOSIZE;
        wsize = min_t(unsigned int, wsize, server->max_write);
#ifdef CONFIG_CIFS_SMB_DIRECT
        if (server->rdma) {
                if (server->sign)
                        /*
                         * Account for SMB2 data transfer packet header and
                         * possible encryption header
                         */
                        wsize = min_t(unsigned int,
                                wsize,
                                server->smbd_conn->max_fragmented_send_size -
                                        SMB2_READWRITE_PDU_HEADER_SIZE -
                                        sizeof(struct smb2_transform_hdr));
                else
                        wsize = min_t(unsigned int,
                                wsize, server->smbd_conn->max_readwrite_size);
        }
#endif
        if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
                wsize = min_t(unsigned int, wsize, SMB2_MAX_BUFFER_SIZE);

        return wsize;
}

static unsigned int
smb2_negotiate_rsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int rsize;

        /* start with specified rsize, or default */
        rsize = ctx->rsize ? ctx->rsize : CIFS_DEFAULT_IOSIZE;
        rsize = min_t(unsigned int, rsize, server->max_read);

        if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
                rsize = min_t(unsigned int, rsize, SMB2_MAX_BUFFER_SIZE);

        return rsize;
}

static unsigned int
smb3_negotiate_rsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int rsize;

        /* start with specified rsize, or default */
        rsize = ctx->rsize ? ctx->rsize : SMB3_DEFAULT_IOSIZE;
        rsize = min_t(unsigned int, rsize, server->max_read);
#ifdef CONFIG_CIFS_SMB_DIRECT
        if (server->rdma) {
                if (server->sign)
                        /*
                         * Account for SMB2 data transfer packet header and
                         * possible encryption header
                         */
                        rsize = min_t(unsigned int,
                                rsize,
                                server->smbd_conn->max_fragmented_recv_size -
                                        SMB2_READWRITE_PDU_HEADER_SIZE -
                                        sizeof(struct smb2_transform_hdr));
                else
                        rsize = min_t(unsigned int,
                                rsize, server->smbd_conn->max_readwrite_size);
        }
#endif

        if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
                rsize = min_t(unsigned int, rsize, SMB2_MAX_BUFFER_SIZE);

        return rsize;
}

static int
parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf,
                        size_t buf_len,
                        struct cifs_server_iface **iface_list,
                        size_t *iface_count)
{
        struct network_interface_info_ioctl_rsp *p;
        struct sockaddr_in *addr4;
        struct sockaddr_in6 *addr6;
        struct iface_info_ipv4 *p4;
        struct iface_info_ipv6 *p6;
        struct cifs_server_iface *info;
        ssize_t bytes_left;
        size_t next = 0;
        int nb_iface = 0;
        int rc = 0;

        *iface_list = NULL;
        *iface_count = 0;

        /*
         * Fist pass: count and sanity check
         */

        bytes_left = buf_len;
        p = buf;
        while (bytes_left >= sizeof(*p)) {
                nb_iface++;
                next = le32_to_cpu(p->Next);
                if (!next) {
                        bytes_left -= sizeof(*p);
                        break;
                }
                p = (struct network_interface_info_ioctl_rsp *)((u8 *)p+next);
                bytes_left -= next;
        }

        if (!nb_iface) {
                cifs_dbg(VFS, "%s: malformed interface info\n", __func__);
                rc = -EINVAL;
                goto out;
        }

        /* Azure rounds the buffer size up 8, to a 16 byte boundary */
        if ((bytes_left > 8) || p->Next)
                cifs_dbg(VFS, "%s: incomplete interface info\n", __func__);


        /*
         * Second pass: extract info to internal structure
         */

        *iface_list = kcalloc(nb_iface, sizeof(**iface_list), GFP_KERNEL);
        if (!*iface_list) {
                rc = -ENOMEM;
                goto out;
        }

        info = *iface_list;
        bytes_left = buf_len;
        p = buf;
        while (bytes_left >= sizeof(*p)) {
                info->speed = le64_to_cpu(p->LinkSpeed);
                info->rdma_capable = le32_to_cpu(p->Capability & RDMA_CAPABLE) ? 1 : 0;
                info->rss_capable = le32_to_cpu(p->Capability & RSS_CAPABLE) ? 1 : 0;

                cifs_dbg(FYI, "%s: adding iface %zu\n", __func__, *iface_count);
                cifs_dbg(FYI, "%s: speed %zu bps\n", __func__, info->speed);
                cifs_dbg(FYI, "%s: capabilities 0x%08x\n", __func__,
                         le32_to_cpu(p->Capability));

                switch (p->Family) {
                /*
                 * The kernel and wire socket structures have the same
                 * layout and use network byte order but make the
                 * conversion explicit in case either one changes.
                 */
                case INTERNETWORK:
                        addr4 = (struct sockaddr_in *)&info->sockaddr;
                        p4 = (struct iface_info_ipv4 *)p->Buffer;
                        addr4->sin_family = AF_INET;
                        memcpy(&addr4->sin_addr, &p4->IPv4Address, 4);

                        /* [MS-SMB2] 2.2.32.5.1.1 Clients MUST ignore these */
                        addr4->sin_port = cpu_to_be16(CIFS_PORT);

                        cifs_dbg(FYI, "%s: ipv4 %pI4\n", __func__,
                                 &addr4->sin_addr);
                        break;
                case INTERNETWORKV6:
                        addr6 = (struct sockaddr_in6 *)&info->sockaddr;
                        p6 = (struct iface_info_ipv6 *)p->Buffer;
                        addr6->sin6_family = AF_INET6;
                        memcpy(&addr6->sin6_addr, &p6->IPv6Address, 16);

                        /* [MS-SMB2] 2.2.32.5.1.2 Clients MUST ignore these */
                        addr6->sin6_flowinfo = 0;
                        addr6->sin6_scope_id = 0;
                        addr6->sin6_port = cpu_to_be16(CIFS_PORT);

                        cifs_dbg(FYI, "%s: ipv6 %pI6\n", __func__,
                                 &addr6->sin6_addr);
                        break;
                default:
                        cifs_dbg(VFS,
                                 "%s: skipping unsupported socket family\n",
                                 __func__);
                        goto next_iface;
                }

                (*iface_count)++;
                info++;
next_iface:
                next = le32_to_cpu(p->Next);
                if (!next)
                        break;
                p = (struct network_interface_info_ioctl_rsp *)((u8 *)p+next);
                bytes_left -= next;
        }

        if (!*iface_count) {
                rc = -EINVAL;
                goto out;
        }

out:
        if (rc) {
                kfree(*iface_list);
                *iface_count = 0;
                *iface_list = NULL;
        }
        return rc;
}

static int compare_iface(const void *ia, const void *ib)
{
        const struct cifs_server_iface *a = (struct cifs_server_iface *)ia;
        const struct cifs_server_iface *b = (struct cifs_server_iface *)ib;

        return a->speed == b->speed ? 0 : (a->speed > b->speed ? -1 : 1);
}

static int
SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon)
{
        int rc;
        unsigned int ret_data_len = 0;
        struct network_interface_info_ioctl_rsp *out_buf = NULL;
        struct cifs_server_iface *iface_list;
        size_t iface_count;
        struct cifs_ses *ses = tcon->ses;

        rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
                        FSCTL_QUERY_NETWORK_INTERFACE_INFO, true /* is_fsctl */,
                        NULL /* no data input */, 0 /* no data input */,
                        CIFSMaxBufSize, (char **)&out_buf, &ret_data_len);
        if (rc == -EOPNOTSUPP) {
                cifs_dbg(FYI,
                         "server does not support query network interfaces\n");
                goto out;
        } else if (rc != 0) {
                cifs_tcon_dbg(VFS, "error %d on ioctl to get interface list\n", rc);
                goto out;
        }

        rc = parse_server_interfaces(out_buf, ret_data_len,
                                     &iface_list, &iface_count);
        if (rc)
                goto out;

        /* sort interfaces from fastest to slowest */
        sort(iface_list, iface_count, sizeof(*iface_list), compare_iface, NULL);

        spin_lock(&ses->iface_lock);
        kfree(ses->iface_list);
        ses->iface_list = iface_list;
        ses->iface_count = iface_count;
        ses->iface_last_update = jiffies;
        spin_unlock(&ses->iface_lock);

out:
        kfree(out_buf);
        return rc;
}

static void
smb2_close_cached_fid(struct kref *ref)
{
        struct cached_fid *cfid = container_of(ref, struct cached_fid,
                                               refcount);

        if (cfid->is_valid) {
                cifs_dbg(FYI, "clear cached root file handle\n");
                SMB2_close(0, cfid->tcon, cfid->fid->persistent_fid,
                           cfid->fid->volatile_fid);
        }

        /*
         * We only check validity above to send SMB2_close,
         * but we still need to invalidate these entries
         * when this function is called
         */
        cfid->is_valid = false;
        cfid->file_all_info_is_valid = false;
        cfid->has_lease = false;
        if (cfid->dentry) {
                dput(cfid->dentry);
                cfid->dentry = NULL;
        }
}

void close_cached_dir(struct cached_fid *cfid)
{
        mutex_lock(&cfid->fid_mutex);
        kref_put(&cfid->refcount, smb2_close_cached_fid);
        mutex_unlock(&cfid->fid_mutex);
}

void close_cached_dir_lease_locked(struct cached_fid *cfid)
{
        if (cfid->has_lease) {
                cfid->has_lease = false;
                kref_put(&cfid->refcount, smb2_close_cached_fid);
        }
}

void close_cached_dir_lease(struct cached_fid *cfid)
{
        mutex_lock(&cfid->fid_mutex);
        close_cached_dir_lease_locked(cfid);
        mutex_unlock(&cfid->fid_mutex);
}

void
smb2_cached_lease_break(struct work_struct *work)
{
        struct cached_fid *cfid = container_of(work,
                                struct cached_fid, lease_break);

        close_cached_dir_lease(cfid);
}

/*
 * Open the and cache a directory handle.
 * Only supported for the root handle.
 */
int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon,
                const char *path,
                struct cifs_sb_info *cifs_sb,
                struct cached_fid **cfid)
{
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = ses->server;
        struct cifs_open_parms oparms;
        struct smb2_create_rsp *o_rsp = NULL;
        struct smb2_query_info_rsp *qi_rsp = NULL;
        int resp_buftype[2];
        struct smb_rqst rqst[2];
        struct kvec rsp_iov[2];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec qi_iov[1];
        int rc, flags = 0;
        __le16 utf16_path = 0; /* Null - since an open of top of share */
        u8 oplock = SMB2_OPLOCK_LEVEL_II;
        struct cifs_fid *pfid;
        struct dentry *dentry;

        if (tcon->nohandlecache)
                return -ENOTSUPP;

        if (cifs_sb->root == NULL)
                return -ENOENT;

        if (strlen(path))
                return -ENOENT;

        dentry = cifs_sb->root;

        mutex_lock(&tcon->crfid.fid_mutex);
        if (tcon->crfid.is_valid) {
                cifs_dbg(FYI, "found a cached root file handle\n");
                *cfid = &tcon->crfid;
                kref_get(&tcon->crfid.refcount);
                mutex_unlock(&tcon->crfid.fid_mutex);
                return 0;
        }

        /*
         * We do not hold the lock for the open because in case
         * SMB2_open needs to reconnect, it will end up calling
         * cifs_mark_open_files_invalid() which takes the lock again
         * thus causing a deadlock
         */

        mutex_unlock(&tcon->crfid.fid_mutex);

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        if (!server->ops->new_lease_key)
                return -EIO;

        pfid = tcon->crfid.fid;
        server->ops->new_lease_key(pfid);

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        /* Open */
        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        oparms.tcon = tcon;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.fid = pfid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, &utf16_path);
        if (rc)
                goto oshr_free;
        smb2_set_next_command(tcon, &rqst[0]);

        memset(&qi_iov, 0, sizeof(qi_iov));
        rqst[1].rq_iov = qi_iov;
        rqst[1].rq_nvec = 1;

        rc = SMB2_query_info_init(tcon, server,
                                  &rqst[1], COMPOUND_FID,
                                  COMPOUND_FID, FILE_ALL_INFORMATION,
                                  SMB2_O_INFO_FILE, 0,
                                  sizeof(struct smb2_file_all_info) +
                                  PATH_MAX * 2, 0, NULL);
        if (rc)
                goto oshr_free;

        smb2_set_related(&rqst[1]);

        rc = compound_send_recv(xid, ses, server,
                                flags, 2, rqst,
                                resp_buftype, rsp_iov);
        mutex_lock(&tcon->crfid.fid_mutex);

        /*
         * Now we need to check again as the cached root might have
         * been successfully re-opened from a concurrent process
         */

        if (tcon->crfid.is_valid) {
                /* work was already done */

                /* stash fids for close() later */
                struct cifs_fid fid = {
                        .persistent_fid = pfid->persistent_fid,
                        .volatile_fid = pfid->volatile_fid,
                };

                /*
                 * caller expects this func to set the fid in crfid to valid
                 * cached root, so increment the refcount.
                 */
                kref_get(&tcon->crfid.refcount);

                mutex_unlock(&tcon->crfid.fid_mutex);

                if (rc == 0) {
                        /* close extra handle outside of crit sec */
                        SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
                }
                rc = 0;
                goto oshr_free;
        }

        /* Cached root is still invalid, continue normaly */

        if (rc) {
                if (rc == -EREMCHG) {
                        tcon->need_reconnect = true;
                        pr_warn_once("server share %s deleted\n",
                                     tcon->treeName);
                }
                goto oshr_exit;
        }

        atomic_inc(&tcon->num_remote_opens);

        o_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
        oparms.fid->persistent_fid = o_rsp->PersistentFileId;
        oparms.fid->volatile_fid = o_rsp->VolatileFileId;
#ifdef CONFIG_CIFS_DEBUG2
        oparms.fid->mid = le64_to_cpu(o_rsp->sync_hdr.MessageId);
#endif /* CIFS_DEBUG2 */

        tcon->crfid.tcon = tcon;
        tcon->crfid.is_valid = true;
        tcon->crfid.dentry = dentry;
        dget(dentry);
        kref_init(&tcon->crfid.refcount);

        /* BB TBD check to see if oplock level check can be removed below */
        if (o_rsp->OplockLevel == SMB2_OPLOCK_LEVEL_LEASE) {
                /*
                 * See commit 2f94a3125b87. Increment the refcount when we
                 * get a lease for root, release it if lease break occurs
                 */
                kref_get(&tcon->crfid.refcount);
                tcon->crfid.has_lease = true;
                smb2_parse_contexts(server, o_rsp,
                                &oparms.fid->epoch,
                                    oparms.fid->lease_key, &oplock,
                                    NULL, NULL);
        } else
                goto oshr_exit;

        qi_rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
        if (le32_to_cpu(qi_rsp->OutputBufferLength) < sizeof(struct smb2_file_all_info))
                goto oshr_exit;
        if (!smb2_validate_and_copy_iov(
                                le16_to_cpu(qi_rsp->OutputBufferOffset),
                                sizeof(struct smb2_file_all_info),
                                &rsp_iov[1], sizeof(struct smb2_file_all_info),
                                (char *)&tcon->crfid.file_all_info))
                tcon->crfid.file_all_info_is_valid = true;
        tcon->crfid.time = jiffies;


oshr_exit:
        mutex_unlock(&tcon->crfid.fid_mutex);
oshr_free:
        SMB2_open_free(&rqst[0]);
        SMB2_query_info_free(&rqst[1]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        if (rc == 0)
                *cfid = &tcon->crfid;
        return rc;
}

int open_cached_dir_by_dentry(struct cifs_tcon *tcon,
                              struct dentry *dentry,
                              struct cached_fid **cfid)
{
        mutex_lock(&tcon->crfid.fid_mutex);
        if (tcon->crfid.dentry == dentry) {
                cifs_dbg(FYI, "found a cached root file handle by dentry\n");
                *cfid = &tcon->crfid;
                kref_get(&tcon->crfid.refcount);
                mutex_unlock(&tcon->crfid.fid_mutex);
                return 0;
        }
        mutex_unlock(&tcon->crfid.fid_mutex);
        return -ENOENT;
}

static void
smb3_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon,
              struct cifs_sb_info *cifs_sb)
{
        int rc;
        __le16 srch_path = 0; /* Null - open root of share */
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        struct cached_fid *cfid = NULL;

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = open_cached_dir(xid, tcon, "", cifs_sb, &cfid);
        if (rc == 0)
                memcpy(&fid, cfid->fid, sizeof(struct cifs_fid));
        else
                rc = SMB2_open(xid, &oparms, &srch_path, &oplock, NULL, NULL,
                               NULL, NULL);
        if (rc)
                return;

        SMB3_request_interfaces(xid, tcon);

        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_ATTRIBUTE_INFORMATION);
        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_DEVICE_INFORMATION);
        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_VOLUME_INFORMATION);
        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_SECTOR_SIZE_INFORMATION); /* SMB3 specific */
        if (cfid == NULL)
                SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        else
                close_cached_dir(cfid);
}

static void
smb2_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon,
              struct cifs_sb_info *cifs_sb)

{
        int rc;
        __le16 srch_path = 0; /* Null - open root of share */
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, &srch_path, &oplock, NULL, NULL,
                       NULL, NULL);
        if (rc)
                return;

        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_ATTRIBUTE_INFORMATION);
        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_DEVICE_INFORMATION);
        SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
}

static int
smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
                        struct cifs_sb_info *cifs_sb, const char *full_path)
{
        int rc;
        __le16 *utf16_path;
        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;

        if ((*full_path == 0) && tcon->crfid.is_valid)
                return 0;

        utf16_path = cifs_convert_path_to_utf16(full_path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL, NULL,
                       NULL);
        if (rc) {
                kfree(utf16_path);
                return rc;
        }

        rc = SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        kfree(utf16_path);
        return rc;
}

static int
smb2_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)
{
        *uniqueid = le64_to_cpu(data->IndexNumber);
        return 0;
}

static int
smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
                     struct cifs_fid *fid, FILE_ALL_INFO *data)
{
        int rc;
        struct smb2_file_all_info *smb2_data;

        smb2_data = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
                            GFP_KERNEL);
        if (smb2_data == NULL)
                return -ENOMEM;

        rc = SMB2_query_info(xid, tcon, fid->persistent_fid, fid->volatile_fid,
                             smb2_data);
        if (!rc)
                move_smb2_info_to_cifs(data, smb2_data);
        kfree(smb2_data);
        return rc;
}

#ifdef CONFIG_CIFS_XATTR
static ssize_t
move_smb2_ea_to_cifs(char *dst, size_t dst_size,
                     struct smb2_file_full_ea_info *src, size_t src_size,
                     const unsigned char *ea_name)
{
        int rc = 0;
        unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0;
        char *name, *value;
        size_t buf_size = dst_size;
        size_t name_len, value_len, user_name_len;

        while (src_size > 0) {
                name = &src->ea_data[0];
                name_len = (size_t)src->ea_name_length;
                value = &src->ea_data[src->ea_name_length + 1];
                value_len = (size_t)le16_to_cpu(src->ea_value_length);

                if (name_len == 0)
                        break;

                if (src_size < 8 + name_len + 1 + value_len) {
                        cifs_dbg(FYI, "EA entry goes beyond length of list\n");
                        rc = -EIO;
                        goto out;
                }

                if (ea_name) {
                        if (ea_name_len == name_len &&
                            memcmp(ea_name, name, name_len) == 0) {
                                rc = value_len;
                                if (dst_size == 0)
                                        goto out;
                                if (dst_size < value_len) {
                                        rc = -ERANGE;
                                        goto out;
                                }
                                memcpy(dst, value, value_len);
                                goto out;
                        }
                } else {
                        /* 'user.' plus a terminating null */
                        user_name_len = 5 + 1 + name_len;

                        if (buf_size == 0) {
                                /* skip copy - calc size only */
                                rc += user_name_len;
                        } else if (dst_size >= user_name_len) {
                                dst_size -= user_name_len;
                                memcpy(dst, "user.", 5);
                                dst += 5;
                                memcpy(dst, src->ea_data, name_len);
                                dst += name_len;
                                *dst = 0;
                                ++dst;
                                rc += user_name_len;
                        } else {
                                /* stop before overrun buffer */
                                rc = -ERANGE;
                                break;
                        }
                }

                if (!src->next_entry_offset)
                        break;

                if (src_size < le32_to_cpu(src->next_entry_offset)) {
                        /* stop before overrun buffer */
                        rc = -ERANGE;
                        break;
                }
                src_size -= le32_to_cpu(src->next_entry_offset);
                src = (void *)((char *)src +
                               le32_to_cpu(src->next_entry_offset));
        }

        /* didn't find the named attribute */
        if (ea_name)
                rc = -ENODATA;

out:
        return (ssize_t)rc;
}

static ssize_t
smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
               const unsigned char *path, const unsigned char *ea_name,
               char *ea_data, size_t buf_size,
               struct cifs_sb_info *cifs_sb)
{
        int rc;
        __le16 *utf16_path;
        struct kvec rsp_iov = {NULL, 0};
        int buftype = CIFS_NO_BUFFER;
        struct smb2_query_info_rsp *rsp;
        struct smb2_file_full_ea_info *info = NULL;

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        rc = smb2_query_info_compound(xid, tcon, utf16_path,
                                      FILE_READ_EA,
                                      FILE_FULL_EA_INFORMATION,
                                      SMB2_O_INFO_FILE,
                                      CIFSMaxBufSize -
                                      MAX_SMB2_CREATE_RESPONSE_SIZE -
                                      MAX_SMB2_CLOSE_RESPONSE_SIZE,
                                      &rsp_iov, &buftype, cifs_sb);
        if (rc) {
                /*
                 * If ea_name is NULL (listxattr) and there are no EAs,
                 * return 0 as it's not an error. Otherwise, the specified
                 * ea_name was not found.
                 */
                if (!ea_name && rc == -ENODATA)
                        rc = 0;
                goto qeas_exit;
        }

        rsp = (struct smb2_query_info_rsp *)rsp_iov.iov_base;
        rc = smb2_validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
                               le32_to_cpu(rsp->OutputBufferLength),
                               &rsp_iov,
                               sizeof(struct smb2_file_full_ea_info));
        if (rc)
                goto qeas_exit;

        info = (struct smb2_file_full_ea_info *)(
                        le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
        rc = move_smb2_ea_to_cifs(ea_data, buf_size, info,
                        le32_to_cpu(rsp->OutputBufferLength), ea_name);

 qeas_exit:
        kfree(utf16_path);
        free_rsp_buf(buftype, rsp_iov.iov_base);
        return rc;
}


static int
smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
            const char *path, const char *ea_name, const void *ea_value,
            const __u16 ea_value_len, const struct nls_table *nls_codepage,
            struct cifs_sb_info *cifs_sb)
{
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = cifs_pick_channel(ses);
        __le16 *utf16_path = NULL;
        int ea_name_len = strlen(ea_name);
        int flags = CIFS_CP_CREATE_CLOSE_OP;
        int len;
        struct smb_rqst rqst[3];
        int resp_buftype[3];
        struct kvec rsp_iov[3];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct cifs_open_parms oparms;
        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_fid fid;
        struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
        unsigned int size[1];
        void *data[1];
        struct smb2_file_full_ea_info *ea = NULL;
        struct kvec close_iov[1];
        struct smb2_query_info_rsp *rsp;
        int rc, used_len = 0;

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        if (ea_name_len > 255)
                return -EINVAL;

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        if (ses->server->ops->query_all_EAs) {
                if (!ea_value) {
                        rc = ses->server->ops->query_all_EAs(xid, tcon, path,
                                                             ea_name, NULL, 0,
                                                             cifs_sb);
                        if (rc == -ENODATA)
                                goto sea_exit;
                } else {
                        /* If we are adding a attribute we should first check
                         * if there will be enough space available to store
                         * the new EA. If not we should not add it since we
                         * would not be able to even read the EAs back.
                         */
                        rc = smb2_query_info_compound(xid, tcon, utf16_path,
                                      FILE_READ_EA,
                                      FILE_FULL_EA_INFORMATION,
                                      SMB2_O_INFO_FILE,
                                      CIFSMaxBufSize -
                                      MAX_SMB2_CREATE_RESPONSE_SIZE -
                                      MAX_SMB2_CLOSE_RESPONSE_SIZE,
                                      &rsp_iov[1], &resp_buftype[1], cifs_sb);
                        if (rc == 0) {
                                rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
                                used_len = le32_to_cpu(rsp->OutputBufferLength);
                        }
                        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
                        resp_buftype[1] = CIFS_NO_BUFFER;
                        memset(&rsp_iov[1], 0, sizeof(rsp_iov[1]));
                        rc = 0;

                        /* Use a fudge factor of 256 bytes in case we collide
                         * with a different set_EAs command.
                         */
                        if(CIFSMaxBufSize - MAX_SMB2_CREATE_RESPONSE_SIZE -
                           MAX_SMB2_CLOSE_RESPONSE_SIZE - 256 <
                           used_len + ea_name_len + ea_value_len + 1) {
                                rc = -ENOSPC;
                                goto sea_exit;
                        }
                }
        }

        /* Open */
        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        memset(&oparms, 0, sizeof(oparms));
        oparms.tcon = tcon;
        oparms.desired_access = FILE_WRITE_EA;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, utf16_path);
        if (rc)
                goto sea_exit;
        smb2_set_next_command(tcon, &rqst[0]);


        /* Set Info */
        memset(&si_iov, 0, sizeof(si_iov));
        rqst[1].rq_iov = si_iov;
        rqst[1].rq_nvec = 1;

        len = sizeof(*ea) + ea_name_len + ea_value_len + 1;
        ea = kzalloc(len, GFP_KERNEL);
        if (ea == NULL) {
                rc = -ENOMEM;
                goto sea_exit;
        }

        ea->ea_name_length = ea_name_len;
        ea->ea_value_length = cpu_to_le16(ea_value_len);
        memcpy(ea->ea_data, ea_name, ea_name_len + 1);
        memcpy(ea->ea_data + ea_name_len + 1, ea_value, ea_value_len);

        size[0] = len;
        data[0] = ea;

        rc = SMB2_set_info_init(tcon, server,
                                &rqst[1], COMPOUND_FID,
                                COMPOUND_FID, current->tgid,
                                FILE_FULL_EA_INFORMATION,
                                SMB2_O_INFO_FILE, 0, data, size);
        smb2_set_next_command(tcon, &rqst[1]);
        smb2_set_related(&rqst[1]);


        /* Close */
        memset(&close_iov, 0, sizeof(close_iov));
        rqst[2].rq_iov = close_iov;
        rqst[2].rq_nvec = 1;
        rc = SMB2_close_init(tcon, server,
                             &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
        smb2_set_related(&rqst[2]);

        rc = compound_send_recv(xid, ses, server,
                                flags, 3, rqst,
                                resp_buftype, rsp_iov);
        /* no need to bump num_remote_opens because handle immediately closed */

 sea_exit:
        kfree(ea);
        kfree(utf16_path);
        SMB2_open_free(&rqst[0]);
        SMB2_set_info_free(&rqst[1]);
        SMB2_close_free(&rqst[2]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
        return rc;
}
#endif

static bool
smb2_can_echo(struct TCP_Server_Info *server)
{
        return server->echoes;
}

static void
smb2_clear_stats(struct cifs_tcon *tcon)
{
        int i;

        for (i = 0; i < NUMBER_OF_SMB2_COMMANDS; i++) {
                atomic_set(&tcon->stats.smb2_stats.smb2_com_sent[i], 0);
                atomic_set(&tcon->stats.smb2_stats.smb2_com_failed[i], 0);
        }
}

static void
smb2_dump_share_caps(struct seq_file *m, struct cifs_tcon *tcon)
{
        seq_puts(m, "\n\tShare Capabilities:");
        if (tcon->capabilities & SMB2_SHARE_CAP_DFS)
                seq_puts(m, " DFS,");
        if (tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
                seq_puts(m, " CONTINUOUS AVAILABILITY,");
        if (tcon->capabilities & SMB2_SHARE_CAP_SCALEOUT)
                seq_puts(m, " SCALEOUT,");
        if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER)
                seq_puts(m, " CLUSTER,");
        if (tcon->capabilities & SMB2_SHARE_CAP_ASYMMETRIC)
                seq_puts(m, " ASYMMETRIC,");
        if (tcon->capabilities == 0)
                seq_puts(m, " None");
        if (tcon->ss_flags & SSINFO_FLAGS_ALIGNED_DEVICE)
                seq_puts(m, " Aligned,");
        if (tcon->ss_flags & SSINFO_FLAGS_PARTITION_ALIGNED_ON_DEVICE)
                seq_puts(m, " Partition Aligned,");
        if (tcon->ss_flags & SSINFO_FLAGS_NO_SEEK_PENALTY)
                seq_puts(m, " SSD,");
        if (tcon->ss_flags & SSINFO_FLAGS_TRIM_ENABLED)
                seq_puts(m, " TRIM-support,");

        seq_printf(m, "\tShare Flags: 0x%x", tcon->share_flags);
        seq_printf(m, "\n\ttid: 0x%x", tcon->tid);
        if (tcon->perf_sector_size)
                seq_printf(m, "\tOptimal sector size: 0x%x",
                           tcon->perf_sector_size);
        seq_printf(m, "\tMaximal Access: 0x%x", tcon->maximal_access);
}

static void
smb2_print_stats(struct seq_file *m, struct cifs_tcon *tcon)
{
        atomic_t *sent = tcon->stats.smb2_stats.smb2_com_sent;
        atomic_t *failed = tcon->stats.smb2_stats.smb2_com_failed;

        /*
         *  Can't display SMB2_NEGOTIATE, SESSION_SETUP, LOGOFF, CANCEL and ECHO
         *  totals (requests sent) since those SMBs are per-session not per tcon
         */
        seq_printf(m, "\nBytes read: %llu  Bytes written: %llu",
                   (long long)(tcon->bytes_read),
                   (long long)(tcon->bytes_written));
        seq_printf(m, "\nOpen files: %d total (local), %d open on server",
                   atomic_read(&tcon->num_local_opens),
                   atomic_read(&tcon->num_remote_opens));
        seq_printf(m, "\nTreeConnects: %d total %d failed",
                   atomic_read(&sent[SMB2_TREE_CONNECT_HE]),
                   atomic_read(&failed[SMB2_TREE_CONNECT_HE]));
        seq_printf(m, "\nTreeDisconnects: %d total %d failed",
                   atomic_read(&sent[SMB2_TREE_DISCONNECT_HE]),
                   atomic_read(&failed[SMB2_TREE_DISCONNECT_HE]));
        seq_printf(m, "\nCreates: %d total %d failed",
                   atomic_read(&sent[SMB2_CREATE_HE]),
                   atomic_read(&failed[SMB2_CREATE_HE]));
        seq_printf(m, "\nCloses: %d total %d failed",
                   atomic_read(&sent[SMB2_CLOSE_HE]),
                   atomic_read(&failed[SMB2_CLOSE_HE]));
        seq_printf(m, "\nFlushes: %d total %d failed",
                   atomic_read(&sent[SMB2_FLUSH_HE]),
                   atomic_read(&failed[SMB2_FLUSH_HE]));
        seq_printf(m, "\nReads: %d total %d failed",
                   atomic_read(&sent[SMB2_READ_HE]),
                   atomic_read(&failed[SMB2_READ_HE]));
        seq_printf(m, "\nWrites: %d total %d failed",
                   atomic_read(&sent[SMB2_WRITE_HE]),
                   atomic_read(&failed[SMB2_WRITE_HE]));
        seq_printf(m, "\nLocks: %d total %d failed",
                   atomic_read(&sent[SMB2_LOCK_HE]),
                   atomic_read(&failed[SMB2_LOCK_HE]));
        seq_printf(m, "\nIOCTLs: %d total %d failed",
                   atomic_read(&sent[SMB2_IOCTL_HE]),
                   atomic_read(&failed[SMB2_IOCTL_HE]));
        seq_printf(m, "\nQueryDirectories: %d total %d failed",
                   atomic_read(&sent[SMB2_QUERY_DIRECTORY_HE]),
                   atomic_read(&failed[SMB2_QUERY_DIRECTORY_HE]));
        seq_printf(m, "\nChangeNotifies: %d total %d failed",
                   atomic_read(&sent[SMB2_CHANGE_NOTIFY_HE]),
                   atomic_read(&failed[SMB2_CHANGE_NOTIFY_HE]));
        seq_printf(m, "\nQueryInfos: %d total %d failed",
                   atomic_read(&sent[SMB2_QUERY_INFO_HE]),
                   atomic_read(&failed[SMB2_QUERY_INFO_HE]));
        seq_printf(m, "\nSetInfos: %d total %d failed",
                   atomic_read(&sent[SMB2_SET_INFO_HE]),
                   atomic_read(&failed[SMB2_SET_INFO_HE]));
        seq_printf(m, "\nOplockBreaks: %d sent %d failed",
                   atomic_read(&sent[SMB2_OPLOCK_BREAK_HE]),
                   atomic_read(&failed[SMB2_OPLOCK_BREAK_HE]));
}

static void
smb2_set_fid(struct cifsFileInfo *cfile, struct cifs_fid *fid, __u32 oplock)
{
        struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
        struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;

        cfile->fid.persistent_fid = fid->persistent_fid;
        cfile->fid.volatile_fid = fid->volatile_fid;
        cfile->fid.access = fid->access;
#ifdef CONFIG_CIFS_DEBUG2
        cfile->fid.mid = fid->mid;
#endif /* CIFS_DEBUG2 */
        server->ops->set_oplock_level(cinode, oplock, fid->epoch,
                                      &fid->purge_cache);
        cinode->can_cache_brlcks = CIFS_CACHE_WRITE(cinode);
        memcpy(cfile->fid.create_guid, fid->create_guid, 16);
}

static void
smb2_close_file(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifs_fid *fid)
{
        SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid);
}

static void
smb2_close_getattr(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile)
{
        struct smb2_file_network_open_info file_inf;
        struct inode *inode;
        int rc;

        rc = __SMB2_close(xid, tcon, cfile->fid.persistent_fid,
                   cfile->fid.volatile_fid, &file_inf);
        if (rc)
                return;

        inode = d_inode(cfile->dentry);

        spin_lock(&inode->i_lock);
        CIFS_I(inode)->time = jiffies;

        /* Creation time should not need to be updated on close */
        if (file_inf.LastWriteTime)
                inode->i_mtime = cifs_NTtimeToUnix(file_inf.LastWriteTime);
        if (file_inf.ChangeTime)
                inode->i_ctime = cifs_NTtimeToUnix(file_inf.ChangeTime);
        if (file_inf.LastAccessTime)
                inode->i_atime = cifs_NTtimeToUnix(file_inf.LastAccessTime);

        /*
         * i_blocks is not related to (i_size / i_blksize),
         * but instead 512 byte (2**9) size is required for
         * calculating num blocks.
         */
        if (le64_to_cpu(file_inf.AllocationSize) > 4096)
                inode->i_blocks =
                        (512 - 1 + le64_to_cpu(file_inf.AllocationSize)) >> 9;

        /* End of file and Attributes should not have to be updated on close */
        spin_unlock(&inode->i_lock);
}

static int
SMB2_request_res_key(const unsigned int xid, struct cifs_tcon *tcon,
                     u64 persistent_fid, u64 volatile_fid,
                     struct copychunk_ioctl *pcchunk)
{
        int rc;
        unsigned int ret_data_len;
        struct resume_key_req *res_key;

        rc = SMB2_ioctl(xid, tcon, persistent_fid, volatile_fid,
                        FSCTL_SRV_REQUEST_RESUME_KEY, true /* is_fsctl */,
                        NULL, 0 /* no input */, CIFSMaxBufSize,
                        (char **)&res_key, &ret_data_len);

        if (rc == -EOPNOTSUPP) {
                pr_warn_once("Server share %s does not support copy range\n", tcon->treeName);
                goto req_res_key_exit;
        } else if (rc) {
                cifs_tcon_dbg(VFS, "refcpy ioctl error %d getting resume key\n", rc);
                goto req_res_key_exit;
        }
        if (ret_data_len < sizeof(struct resume_key_req)) {
                cifs_tcon_dbg(VFS, "Invalid refcopy resume key length\n");
                rc = -EINVAL;
                goto req_res_key_exit;
        }
        memcpy(pcchunk->SourceKey, res_key->ResumeKey, COPY_CHUNK_RES_KEY_SIZE);

req_res_key_exit:
        kfree(res_key);
        return rc;
}

struct iqi_vars {
        struct smb_rqst rqst[3];
        struct kvec rsp_iov[3];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec qi_iov[1];
        struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
        struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
        struct kvec close_iov[1];
};

static int
smb2_ioctl_query_info(const unsigned int xid,
                      struct cifs_tcon *tcon,
                      struct cifs_sb_info *cifs_sb,
                      __le16 *path, int is_dir,
                      unsigned long p)
{
        struct iqi_vars *vars;
        struct smb_rqst *rqst;
        struct kvec *rsp_iov;
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = cifs_pick_channel(ses);
        char __user *arg = (char __user *)p;
        struct smb_query_info qi;
        struct smb_query_info __user *pqi;
        int rc = 0;
        int flags = CIFS_CP_CREATE_CLOSE_OP;
        struct smb2_query_info_rsp *qi_rsp = NULL;
        struct smb2_ioctl_rsp *io_rsp = NULL;
        void *buffer = NULL;
        int resp_buftype[3];
        struct cifs_open_parms oparms;
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_fid fid;
        unsigned int size[2];
        void *data[2];
        int create_options = is_dir ? CREATE_NOT_FILE : CREATE_NOT_DIR;

        vars = kzalloc(sizeof(*vars), GFP_ATOMIC);
        if (vars == NULL)
                return -ENOMEM;
        rqst = &vars->rqst[0];
        rsp_iov = &vars->rsp_iov[0];

        resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;

        if (copy_from_user(&qi, arg, sizeof(struct smb_query_info)))
                goto e_fault;

        if (qi.output_buffer_length > 1024) {
                kfree(vars);
                return -EINVAL;
        }

        if (!ses || !server) {
                kfree(vars);
                return -EIO;
        }

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        buffer = memdup_user(arg + sizeof(struct smb_query_info),
                             qi.output_buffer_length);
        if (IS_ERR(buffer)) {
                kfree(vars);
                return PTR_ERR(buffer);
        }

        /* Open */
        rqst[0].rq_iov = &vars->open_iov[0];
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        memset(&oparms, 0, sizeof(oparms));
        oparms.tcon = tcon;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, create_options);
        oparms.fid = &fid;
        oparms.reconnect = false;

        if (qi.flags & PASSTHRU_FSCTL) {
                switch (qi.info_type & FSCTL_DEVICE_ACCESS_MASK) {
                case FSCTL_DEVICE_ACCESS_FILE_READ_WRITE_ACCESS:
                        oparms.desired_access = FILE_READ_DATA | FILE_WRITE_DATA | FILE_READ_ATTRIBUTES | SYNCHRONIZE;
                        break;
                case FSCTL_DEVICE_ACCESS_FILE_ANY_ACCESS:
                        oparms.desired_access = GENERIC_ALL;
                        break;
                case FSCTL_DEVICE_ACCESS_FILE_READ_ACCESS:
                        oparms.desired_access = GENERIC_READ;
                        break;
                case FSCTL_DEVICE_ACCESS_FILE_WRITE_ACCESS:
                        oparms.desired_access = GENERIC_WRITE;
                        break;
                }
        } else if (qi.flags & PASSTHRU_SET_INFO) {
                oparms.desired_access = GENERIC_WRITE;
        } else {
                oparms.desired_access = FILE_READ_ATTRIBUTES | READ_CONTROL;
        }

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, path);
        if (rc)
                goto iqinf_exit;
        smb2_set_next_command(tcon, &rqst[0]);

        /* Query */
        if (qi.flags & PASSTHRU_FSCTL) {
                /* Can eventually relax perm check since server enforces too */
                if (!capable(CAP_SYS_ADMIN))
                        rc = -EPERM;
                else  {
                        rqst[1].rq_iov = &vars->io_iov[0];
                        rqst[1].rq_nvec = SMB2_IOCTL_IOV_SIZE;

                        rc = SMB2_ioctl_init(tcon, server,
                                             &rqst[1],
                                             COMPOUND_FID, COMPOUND_FID,
                                             qi.info_type, true, buffer,
                                             qi.output_buffer_length,
                                             CIFSMaxBufSize -
                                             MAX_SMB2_CREATE_RESPONSE_SIZE -
                                             MAX_SMB2_CLOSE_RESPONSE_SIZE);
                }
        } else if (qi.flags == PASSTHRU_SET_INFO) {
                /* Can eventually relax perm check since server enforces too */
                if (!capable(CAP_SYS_ADMIN))
                        rc = -EPERM;
                else  {
                        rqst[1].rq_iov = &vars->si_iov[0];
                        rqst[1].rq_nvec = 1;

                        size[0] = 8;
                        data[0] = buffer;

                        rc = SMB2_set_info_init(tcon, server,
                                        &rqst[1],
                                        COMPOUND_FID, COMPOUND_FID,
                                        current->tgid,
                                        FILE_END_OF_FILE_INFORMATION,
                                        SMB2_O_INFO_FILE, 0, data, size);
                }
        } else if (qi.flags == PASSTHRU_QUERY_INFO) {
                rqst[1].rq_iov = &vars->qi_iov[0];
                rqst[1].rq_nvec = 1;

                rc = SMB2_query_info_init(tcon, server,
                                  &rqst[1], COMPOUND_FID,
                                  COMPOUND_FID, qi.file_info_class,
                                  qi.info_type, qi.additional_information,
                                  qi.input_buffer_length,
                                  qi.output_buffer_length, buffer);
        } else { /* unknown flags */
                cifs_tcon_dbg(VFS, "Invalid passthru query flags: 0x%x\n",
                              qi.flags);
                rc = -EINVAL;
        }

        if (rc)
                goto iqinf_exit;
        smb2_set_next_command(tcon, &rqst[1]);
        smb2_set_related(&rqst[1]);

        /* Close */
        rqst[2].rq_iov = &vars->close_iov[0];
        rqst[2].rq_nvec = 1;

        rc = SMB2_close_init(tcon, server,
                             &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
        if (rc)
                goto iqinf_exit;
        smb2_set_related(&rqst[2]);

        rc = compound_send_recv(xid, ses, server,
                                flags, 3, rqst,
                                resp_buftype, rsp_iov);
        if (rc)
                goto iqinf_exit;

        /* No need to bump num_remote_opens since handle immediately closed */
        if (qi.flags & PASSTHRU_FSCTL) {
                pqi = (struct smb_query_info __user *)arg;
                io_rsp = (struct smb2_ioctl_rsp *)rsp_iov[1].iov_base;
                if (le32_to_cpu(io_rsp->OutputCount) < qi.input_buffer_length)
                        qi.input_buffer_length = le32_to_cpu(io_rsp->OutputCount);
                if (qi.input_buffer_length > 0 &&
                    le32_to_cpu(io_rsp->OutputOffset) + qi.input_buffer_length
                    > rsp_iov[1].iov_len)
                        goto e_fault;

                if (copy_to_user(&pqi->input_buffer_length,
                                 &qi.input_buffer_length,
                                 sizeof(qi.input_buffer_length)))
                        goto e_fault;

                if (copy_to_user((void __user *)pqi + sizeof(struct smb_query_info),
                                 (const void *)io_rsp + le32_to_cpu(io_rsp->OutputOffset),
                                 qi.input_buffer_length))
                        goto e_fault;
        } else {
                pqi = (struct smb_query_info __user *)arg;
                qi_rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
                if (le32_to_cpu(qi_rsp->OutputBufferLength) < qi.input_buffer_length)
                        qi.input_buffer_length = le32_to_cpu(qi_rsp->OutputBufferLength);
                if (copy_to_user(&pqi->input_buffer_length,
                                 &qi.input_buffer_length,
                                 sizeof(qi.input_buffer_length)))
                        goto e_fault;

                if (copy_to_user(pqi + 1, qi_rsp->Buffer,
                                 qi.input_buffer_length))
                        goto e_fault;
        }

 iqinf_exit:
        cifs_small_buf_release(rqst[0].rq_iov[0].iov_base);
        cifs_small_buf_release(rqst[1].rq_iov[0].iov_base);
        cifs_small_buf_release(rqst[2].rq_iov[0].iov_base);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
        kfree(vars);
        kfree(buffer);
        return rc;

e_fault:
        rc = -EFAULT;
        goto iqinf_exit;
}

static ssize_t
smb2_copychunk_range(const unsigned int xid,
                        struct cifsFileInfo *srcfile,
                        struct cifsFileInfo *trgtfile, u64 src_off,
                        u64 len, u64 dest_off)
{
        int rc;
        unsigned int ret_data_len;
        struct copychunk_ioctl *pcchunk;
        struct copychunk_ioctl_rsp *retbuf = NULL;
        struct cifs_tcon *tcon;
        int chunks_copied = 0;
        bool chunk_sizes_updated = false;
        ssize_t bytes_written, total_bytes_written = 0;

        pcchunk = kmalloc(sizeof(struct copychunk_ioctl), GFP_KERNEL);

        if (pcchunk == NULL)
                return -ENOMEM;

        cifs_dbg(FYI, "%s: about to call request res key\n", __func__);
        /* Request a key from the server to identify the source of the copy */
        rc = SMB2_request_res_key(xid, tlink_tcon(srcfile->tlink),
                                srcfile->fid.persistent_fid,
                                srcfile->fid.volatile_fid, pcchunk);

        /* Note: request_res_key sets res_key null only if rc !=0 */
        if (rc)
                goto cchunk_out;

        /* For now array only one chunk long, will make more flexible later */
        pcchunk->ChunkCount = cpu_to_le32(1);
        pcchunk->Reserved = 0;
        pcchunk->Reserved2 = 0;

        tcon = tlink_tcon(trgtfile->tlink);

        while (len > 0) {
                pcchunk->SourceOffset = cpu_to_le64(src_off);
                pcchunk->TargetOffset = cpu_to_le64(dest_off);
                pcchunk->Length =
                        cpu_to_le32(min_t(u32, len, tcon->max_bytes_chunk));

                /* Request server copy to target from src identified by key */
                kfree(retbuf);
                retbuf = NULL;
                rc = SMB2_ioctl(xid, tcon, trgtfile->fid.persistent_fid,
                        trgtfile->fid.volatile_fid, FSCTL_SRV_COPYCHUNK_WRITE,
                        true /* is_fsctl */, (char *)pcchunk,
                        sizeof(struct copychunk_ioctl), CIFSMaxBufSize,
                        (char **)&retbuf, &ret_data_len);
                if (rc == 0) {
                        if (ret_data_len !=
                                        sizeof(struct copychunk_ioctl_rsp)) {
                                cifs_tcon_dbg(VFS, "Invalid cchunk response size\n");
                                rc = -EIO;
                                goto cchunk_out;
                        }
                        if (retbuf->TotalBytesWritten == 0) {
                                cifs_dbg(FYI, "no bytes copied\n");
                                rc = -EIO;
                                goto cchunk_out;
                        }
                        /*
                         * Check if server claimed to write more than we asked
                         */
                        if (le32_to_cpu(retbuf->TotalBytesWritten) >
                            le32_to_cpu(pcchunk->Length)) {
                                cifs_tcon_dbg(VFS, "Invalid copy chunk response\n");
                                rc = -EIO;
                                goto cchunk_out;
                        }
                        if (le32_to_cpu(retbuf->ChunksWritten) != 1) {
                                cifs_tcon_dbg(VFS, "Invalid num chunks written\n");
                                rc = -EIO;
                                goto cchunk_out;
                        }
                        chunks_copied++;

                        bytes_written = le32_to_cpu(retbuf->TotalBytesWritten);
                        src_off += bytes_written;
                        dest_off += bytes_written;
                        len -= bytes_written;
                        total_bytes_written += bytes_written;

                        cifs_dbg(FYI, "Chunks %d PartialChunk %d Total %zu\n",
                                le32_to_cpu(retbuf->ChunksWritten),
                                le32_to_cpu(retbuf->ChunkBytesWritten),
                                bytes_written);
                } else if (rc == -EINVAL) {
                        if (ret_data_len != sizeof(struct copychunk_ioctl_rsp))
                                goto cchunk_out;

                        cifs_dbg(FYI, "MaxChunks %d BytesChunk %d MaxCopy %d\n",
                                le32_to_cpu(retbuf->ChunksWritten),
                                le32_to_cpu(retbuf->ChunkBytesWritten),
                                le32_to_cpu(retbuf->TotalBytesWritten));

                        /*
                         * Check if this is the first request using these sizes,
                         * (ie check if copy succeed once with original sizes
                         * and check if the server gave us different sizes after
                         * we already updated max sizes on previous request).
                         * if not then why is the server returning an error now
                         */
                        if ((chunks_copied != 0) || chunk_sizes_updated)
                                goto cchunk_out;

                        /* Check that server is not asking us to grow size */
                        if (le32_to_cpu(retbuf->ChunkBytesWritten) <
                                        tcon->max_bytes_chunk)
                                tcon->max_bytes_chunk =
                                        le32_to_cpu(retbuf->ChunkBytesWritten);
                        else
                                goto cchunk_out; /* server gave us bogus size */

                        /* No need to change MaxChunks since already set to 1 */
                        chunk_sizes_updated = true;
                } else
                        goto cchunk_out;
        }

cchunk_out:
        kfree(pcchunk);
        kfree(retbuf);
        if (rc)
                return rc;
        else
                return total_bytes_written;
}

static int
smb2_flush_file(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifs_fid *fid)
{
        return SMB2_flush(xid, tcon, fid->persistent_fid, fid->volatile_fid);
}

static unsigned int
smb2_read_data_offset(char *buf)
{
        struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;

        return rsp->DataOffset;
}

static unsigned int
smb2_read_data_length(char *buf, bool in_remaining)
{
        struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;

        if (in_remaining)
                return le32_to_cpu(rsp->DataRemaining);

        return le32_to_cpu(rsp->DataLength);
}


static int
smb2_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->persistent_fid = pfid->persistent_fid;
        parms->volatile_fid = pfid->volatile_fid;
        return SMB2_read(xid, parms, bytes_read, buf, buf_type);
}

static int
smb2_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->persistent_fid = pfid->persistent_fid;
        parms->volatile_fid = pfid->volatile_fid;
        return SMB2_write(xid, parms, written, iov, nr_segs);
}

/* Set or clear the SPARSE_FILE attribute based on value passed in setsparse */
static bool smb2_set_sparse(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifsFileInfo *cfile, struct inode *inode, __u8 setsparse)
{
        struct cifsInodeInfo *cifsi;
        int rc;

        cifsi = CIFS_I(inode);

        /* if file already sparse don't bother setting sparse again */
        if ((cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE) && setsparse)
                return true; /* already sparse */

        if (!(cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE) && !setsparse)
                return true; /* already not sparse */

        /*
         * Can't check for sparse support on share the usual way via the
         * FS attribute info (FILE_SUPPORTS_SPARSE_FILES) on the share
         * since Samba server doesn't set the flag on the share, yet
         * supports the set sparse FSCTL and returns sparse correctly
         * in the file attributes. If we fail setting sparse though we
         * mark that server does not support sparse files for this share
         * to avoid repeatedly sending the unsupported fsctl to server
         * if the file is repeatedly extended.
         */
        if (tcon->broken_sparse_sup)
                return false;

        rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid, FSCTL_SET_SPARSE,
                        true /* is_fctl */,
                        &setsparse, 1, CIFSMaxBufSize, NULL, NULL);
        if (rc) {
                tcon->broken_sparse_sup = true;
                cifs_dbg(FYI, "set sparse rc = %d\n", rc);
                return false;
        }

        if (setsparse)
                cifsi->cifsAttrs |= FILE_ATTRIBUTE_SPARSE_FILE;
        else
                cifsi->cifsAttrs &= (~FILE_ATTRIBUTE_SPARSE_FILE);

        return true;
}

static int
smb2_set_file_size(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile, __u64 size, bool set_alloc)
{
        __le64 eof = cpu_to_le64(size);
        struct inode *inode;

        /*
         * If extending file more than one page make sparse. Many Linux fs
         * make files sparse by default when extending via ftruncate
         */
        inode = d_inode(cfile->dentry);

        if (!set_alloc && (size > inode->i_size + 8192)) {
                __u8 set_sparse = 1;

                /* whether set sparse succeeds or not, extend the file */
                smb2_set_sparse(xid, tcon, cfile, inode, set_sparse);
        }

        return SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
                            cfile->fid.volatile_fid, cfile->pid, &eof);
}

static int
smb2_duplicate_extents(const unsigned int xid,
                        struct cifsFileInfo *srcfile,
                        struct cifsFileInfo *trgtfile, u64 src_off,
                        u64 len, u64 dest_off)
{
        int rc;
        unsigned int ret_data_len;
        struct inode *inode;
        struct duplicate_extents_to_file dup_ext_buf;
        struct cifs_tcon *tcon = tlink_tcon(trgtfile->tlink);

        /* server fileays advertise duplicate extent support with this flag */
        if ((le32_to_cpu(tcon->fsAttrInfo.Attributes) &
             FILE_SUPPORTS_BLOCK_REFCOUNTING) == 0)
                return -EOPNOTSUPP;

        dup_ext_buf.VolatileFileHandle = srcfile->fid.volatile_fid;
        dup_ext_buf.PersistentFileHandle = srcfile->fid.persistent_fid;
        dup_ext_buf.SourceFileOffset = cpu_to_le64(src_off);
        dup_ext_buf.TargetFileOffset = cpu_to_le64(dest_off);
        dup_ext_buf.ByteCount = cpu_to_le64(len);
        cifs_dbg(FYI, "Duplicate extents: src off %lld dst off %lld len %lld\n",
                src_off, dest_off, len);

        inode = d_inode(trgtfile->dentry);
        if (inode->i_size < dest_off + len) {
                rc = smb2_set_file_size(xid, tcon, trgtfile, dest_off + len, false);
                if (rc)
                        goto duplicate_extents_out;

                /*
                 * Although also could set plausible allocation size (i_blocks)
                 * here in addition to setting the file size, in reflink
                 * it is likely that the target file is sparse. Its allocation
                 * size will be queried on next revalidate, but it is important
                 * to make sure that file's cached size is updated immediately
                 */
                cifs_setsize(inode, dest_off + len);
        }
        rc = SMB2_ioctl(xid, tcon, trgtfile->fid.persistent_fid,
                        trgtfile->fid.volatile_fid,
                        FSCTL_DUPLICATE_EXTENTS_TO_FILE,
                        true /* is_fsctl */,
                        (char *)&dup_ext_buf,
                        sizeof(struct duplicate_extents_to_file),
                        CIFSMaxBufSize, NULL,
                        &ret_data_len);

        if (ret_data_len > 0)
                cifs_dbg(FYI, "Non-zero response length in duplicate extents\n");

duplicate_extents_out:
        return rc;
}

static int
smb2_set_compression(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile)
{
        return SMB2_set_compression(xid, tcon, cfile->fid.persistent_fid,
                            cfile->fid.volatile_fid);
}

static int
smb3_set_integrity(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile)
{
        struct fsctl_set_integrity_information_req integr_info;
        unsigned int ret_data_len;

        integr_info.ChecksumAlgorithm = cpu_to_le16(CHECKSUM_TYPE_UNCHANGED);
        integr_info.Flags = 0;
        integr_info.Reserved = 0;

        return SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid,
                        FSCTL_SET_INTEGRITY_INFORMATION,
                        true /* is_fsctl */,
                        (char *)&integr_info,
                        sizeof(struct fsctl_set_integrity_information_req),
                        CIFSMaxBufSize, NULL,
                        &ret_data_len);

}

/* GMT Token is @GMT-YYYY.MM.DD-HH.MM.SS Unicode which is 48 bytes + null */
#define GMT_TOKEN_SIZE 50

#define MIN_SNAPSHOT_ARRAY_SIZE 16 /* See MS-SMB2 section 3.3.5.15.1 */

/*
 * Input buffer contains (empty) struct smb_snapshot array with size filled in
 * For output see struct SRV_SNAPSHOT_ARRAY in MS-SMB2 section 2.2.32.2
 */
static int
smb3_enum_snapshots(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile, void __user *ioc_buf)
{
        char *retbuf = NULL;
        unsigned int ret_data_len = 0;
        int rc;
        u32 max_response_size;
        struct smb_snapshot_array snapshot_in;

        /*
         * On the first query to enumerate the list of snapshots available
         * for this volume the buffer begins with 0 (number of snapshots
         * which can be returned is zero since at that point we do not know
         * how big the buffer needs to be). On the second query,
         * it (ret_data_len) is set to number of snapshots so we can
         * know to set the maximum response size larger (see below).
         */
        if (get_user(ret_data_len, (unsigned int __user *)ioc_buf))
                return -EFAULT;

        /*
         * Note that for snapshot queries that servers like Azure expect that
         * the first query be minimal size (and just used to get the number/size
         * of previous versions) so response size must be specified as EXACTLY
         * sizeof(struct snapshot_array) which is 16 when rounded up to multiple
         * of eight bytes.
         */
        if (ret_data_len == 0)
                max_response_size = MIN_SNAPSHOT_ARRAY_SIZE;
        else
                max_response_size = CIFSMaxBufSize;

        rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid,
                        FSCTL_SRV_ENUMERATE_SNAPSHOTS,
                        true /* is_fsctl */,
                        NULL, 0 /* no input data */, max_response_size,
                        (char **)&retbuf,
                        &ret_data_len);
        cifs_dbg(FYI, "enum snaphots ioctl returned %d and ret buflen is %d\n",
                        rc, ret_data_len);
        if (rc)
                return rc;

        if (ret_data_len && (ioc_buf != NULL) && (retbuf != NULL)) {
                /* Fixup buffer */
                if (copy_from_user(&snapshot_in, ioc_buf,
                    sizeof(struct smb_snapshot_array))) {
                        rc = -EFAULT;
                        kfree(retbuf);
                        return rc;
                }

                /*
                 * Check for min size, ie not large enough to fit even one GMT
                 * token (snapshot).  On the first ioctl some users may pass in
                 * smaller size (or zero) to simply get the size of the array
                 * so the user space caller can allocate sufficient memory
                 * and retry the ioctl again with larger array size sufficient
                 * to hold all of the snapshot GMT tokens on the second try.
                 */
                if (snapshot_in.snapshot_array_size < GMT_TOKEN_SIZE)
                        ret_data_len = sizeof(struct smb_snapshot_array);

                /*
                 * We return struct SRV_SNAPSHOT_ARRAY, followed by
                 * the snapshot array (of 50 byte GMT tokens) each
                 * representing an available previous version of the data
                 */
                if (ret_data_len > (snapshot_in.snapshot_array_size +
                                        sizeof(struct smb_snapshot_array)))
                        ret_data_len = snapshot_in.snapshot_array_size +
                                        sizeof(struct smb_snapshot_array);

                if (copy_to_user(ioc_buf, retbuf, ret_data_len))
                        rc = -EFAULT;
        }

        kfree(retbuf);
        return rc;
}



static int
smb3_notify(const unsigned int xid, struct file *pfile,
            void __user *ioc_buf)
{
        struct smb3_notify notify;
        struct dentry *dentry = pfile->f_path.dentry;
        struct inode *inode = file_inode(pfile);
        struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        struct cifs_tcon *tcon;
        const unsigned char *path;
        void *page = alloc_dentry_path();
        __le16 *utf16_path = NULL;
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        int rc = 0;

        path = build_path_from_dentry(dentry, page);
        if (IS_ERR(path)) {
                rc = PTR_ERR(path);
                goto notify_exit;
        }

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (utf16_path == NULL) {
                rc = -ENOMEM;
                goto notify_exit;
        }

        if (copy_from_user(&notify, ioc_buf, sizeof(struct smb3_notify))) {
                rc = -EFAULT;
                goto notify_exit;
        }

        tcon = cifs_sb_master_tcon(cifs_sb);
        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES | FILE_READ_DATA;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL, NULL,
                       NULL);
        if (rc)
                goto notify_exit;

        rc = SMB2_change_notify(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                                notify.watch_tree, notify.completion_filter);

        SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);

        cifs_dbg(FYI, "change notify for path %s rc %d\n", path, rc);

notify_exit:
        free_dentry_path(page);
        kfree(utf16_path);
        return rc;
}

static int
smb2_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)
{
        __le16 *utf16_path;
        struct smb_rqst rqst[2];
        struct kvec rsp_iov[2];
        int resp_buftype[2];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec qd_iov[SMB2_QUERY_DIRECTORY_IOV_SIZE];
        int rc, flags = 0;
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct smb2_query_directory_rsp *qd_rsp = NULL;
        struct smb2_create_rsp *op_rsp = NULL;
        struct TCP_Server_Info *server = cifs_pick_channel(tcon->ses);
        int retry_count = 0;

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        /* Open */
        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES | FILE_READ_DATA;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = fid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, utf16_path);
        if (rc)
                goto qdf_free;
        smb2_set_next_command(tcon, &rqst[0]);

        /* Query directory */
        srch_inf->entries_in_buffer = 0;
        srch_inf->index_of_last_entry = 2;

        memset(&qd_iov, 0, sizeof(qd_iov));
        rqst[1].rq_iov = qd_iov;
        rqst[1].rq_nvec = SMB2_QUERY_DIRECTORY_IOV_SIZE;

        rc = SMB2_query_directory_init(xid, tcon, server,
                                       &rqst[1],
                                       COMPOUND_FID, COMPOUND_FID,
                                       0, srch_inf->info_level);
        if (rc)
                goto qdf_free;

        smb2_set_related(&rqst[1]);

again:
        rc = compound_send_recv(xid, tcon->ses, server,
                                flags, 2, rqst,
                                resp_buftype, rsp_iov);

        if (rc == -EAGAIN && retry_count++ < 10)
                goto again;

        /* If the open failed there is nothing to do */
        op_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
        if (op_rsp == NULL || op_rsp->sync_hdr.Status != STATUS_SUCCESS) {
                cifs_dbg(FYI, "query_dir_first: open failed rc=%d\n", rc);
                goto qdf_free;
        }
        fid->persistent_fid = op_rsp->PersistentFileId;
        fid->volatile_fid = op_rsp->VolatileFileId;

        /* Anything else than ENODATA means a genuine error */
        if (rc && rc != -ENODATA) {
                SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid);
                cifs_dbg(FYI, "query_dir_first: query directory failed rc=%d\n", rc);
                trace_smb3_query_dir_err(xid, fid->persistent_fid,
                                         tcon->tid, tcon->ses->Suid, 0, 0, rc);
                goto qdf_free;
        }

        atomic_inc(&tcon->num_remote_opens);

        qd_rsp = (struct smb2_query_directory_rsp *)rsp_iov[1].iov_base;
        if (qd_rsp->sync_hdr.Status == STATUS_NO_MORE_FILES) {
                trace_smb3_query_dir_done(xid, fid->persistent_fid,
                                          tcon->tid, tcon->ses->Suid, 0, 0);
                srch_inf->endOfSearch = true;
                rc = 0;
                goto qdf_free;
        }

        rc = smb2_parse_query_directory(tcon, &rsp_iov[1], resp_buftype[1],
                                        srch_inf);
        if (rc) {
                trace_smb3_query_dir_err(xid, fid->persistent_fid, tcon->tid,
                        tcon->ses->Suid, 0, 0, rc);
                goto qdf_free;
        }
        resp_buftype[1] = CIFS_NO_BUFFER;

        trace_smb3_query_dir_done(xid, fid->persistent_fid, tcon->tid,
                        tcon->ses->Suid, 0, srch_inf->entries_in_buffer);

 qdf_free:
        kfree(utf16_path);
        SMB2_open_free(&rqst[0]);
        SMB2_query_directory_free(&rqst[1]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        return rc;
}

static int
smb2_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 SMB2_query_directory(xid, tcon, fid->persistent_fid,
                                    fid->volatile_fid, 0, srch_inf);
}

static int
smb2_close_dir(const unsigned int xid, struct cifs_tcon *tcon,
               struct cifs_fid *fid)
{
        return SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid);
}

/*
 * If we negotiate SMB2 protocol and get STATUS_PENDING - update
 * the number of credits and return true. Otherwise - return false.
 */
static bool
smb2_is_status_pending(char *buf, struct TCP_Server_Info *server)
{
        struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
        int scredits, in_flight;

        if (shdr->Status != STATUS_PENDING)
                return false;

        if (shdr->CreditRequest) {
                spin_lock(&server->req_lock);
                server->credits += le16_to_cpu(shdr->CreditRequest);
                scredits = server->credits;
                in_flight = server->in_flight;
                spin_unlock(&server->req_lock);
                wake_up(&server->request_q);

                trace_smb3_add_credits(server->CurrentMid,
                                server->conn_id, server->hostname, scredits,
                                le16_to_cpu(shdr->CreditRequest), in_flight);
                cifs_dbg(FYI, "%s: status pending add %u credits total=%d\n",
                                __func__, le16_to_cpu(shdr->CreditRequest), scredits);
        }

        return true;
}

static bool
smb2_is_session_expired(char *buf)
{
        struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;

        if (shdr->Status != STATUS_NETWORK_SESSION_EXPIRED &&
            shdr->Status != STATUS_USER_SESSION_DELETED)
                return false;

        trace_smb3_ses_expired(shdr->TreeId, shdr->SessionId,
                               le16_to_cpu(shdr->Command),
                               le64_to_cpu(shdr->MessageId));
        cifs_dbg(FYI, "Session expired or deleted\n");

        return true;
}

static bool
smb2_is_status_io_timeout(char *buf)
{
        struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;

        if (shdr->Status == STATUS_IO_TIMEOUT)
                return true;
        else
                return false;
}

static void
smb2_is_network_name_deleted(char *buf, struct TCP_Server_Info *server)
{
        struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
        struct list_head *tmp, *tmp1;
        struct cifs_ses *ses;
        struct cifs_tcon *tcon;

        if (shdr->Status != STATUS_NETWORK_NAME_DELETED)
                return;

        spin_lock(&cifs_tcp_ses_lock);
        list_for_each(tmp, &server->smb_ses_list) {
                ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
                list_for_each(tmp1, &ses->tcon_list) {
                        tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
                        if (tcon->tid == shdr->TreeId) {
                                tcon->need_reconnect = true;
                                spin_unlock(&cifs_tcp_ses_lock);
                                pr_warn_once("Server share %s deleted.\n",
                                             tcon->treeName);
                                return;
                        }
                }
        }
        spin_unlock(&cifs_tcp_ses_lock);
}

static int
smb2_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
                     struct cifsInodeInfo *cinode)
{
        if (tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING)
                return SMB2_lease_break(0, tcon, cinode->lease_key,
                                        smb2_get_lease_state(cinode));

        return SMB2_oplock_break(0, tcon, fid->persistent_fid,
                                 fid->volatile_fid,
                                 CIFS_CACHE_READ(cinode) ? 1 : 0);
}

void
smb2_set_related(struct smb_rqst *rqst)
{
        struct smb2_sync_hdr *shdr;

        shdr = (struct smb2_sync_hdr *)(rqst->rq_iov[0].iov_base);
        if (shdr == NULL) {
                cifs_dbg(FYI, "shdr NULL in smb2_set_related\n");
                return;
        }
        shdr->Flags |= SMB2_FLAGS_RELATED_OPERATIONS;
}

char smb2_padding[7] = {0, 0, 0, 0, 0, 0, 0};

void
smb2_set_next_command(struct cifs_tcon *tcon, struct smb_rqst *rqst)
{
        struct smb2_sync_hdr *shdr;
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = ses->server;
        unsigned long len = smb_rqst_len(server, rqst);
        int i, num_padding;

        shdr = (struct smb2_sync_hdr *)(rqst->rq_iov[0].iov_base);
        if (shdr == NULL) {
                cifs_dbg(FYI, "shdr NULL in smb2_set_next_command\n");
                return;
        }

        /* SMB headers in a compound are 8 byte aligned. */

        /* No padding needed */
        if (!(len & 7))
                goto finished;

        num_padding = 8 - (len & 7);
        if (!smb3_encryption_required(tcon)) {
                /*
                 * If we do not have encryption then we can just add an extra
                 * iov for the padding.
                 */
                rqst->rq_iov[rqst->rq_nvec].iov_base = smb2_padding;
                rqst->rq_iov[rqst->rq_nvec].iov_len = num_padding;
                rqst->rq_nvec++;
                len += num_padding;
        } else {
                /*
                 * We can not add a small padding iov for the encryption case
                 * because the encryption framework can not handle the padding
                 * iovs.
                 * We have to flatten this into a single buffer and add
                 * the padding to it.
                 */
                for (i = 1; i < rqst->rq_nvec; i++) {
                        memcpy(rqst->rq_iov[0].iov_base +
                               rqst->rq_iov[0].iov_len,
                               rqst->rq_iov[i].iov_base,
                               rqst->rq_iov[i].iov_len);
                        rqst->rq_iov[0].iov_len += rqst->rq_iov[i].iov_len;
                }
                memset(rqst->rq_iov[0].iov_base + rqst->rq_iov[0].iov_len,
                       0, num_padding);
                rqst->rq_iov[0].iov_len += num_padding;
                len += num_padding;
                rqst->rq_nvec = 1;
        }

 finished:
        shdr->NextCommand = cpu_to_le32(len);
}

/*
 * Passes the query info response back to the caller on success.
 * Caller need to free this with free_rsp_buf().
 */
int
smb2_query_info_compound(const unsigned int xid, struct cifs_tcon *tcon,
                         __le16 *utf16_path, u32 desired_access,
                         u32 class, u32 type, u32 output_len,
                         struct kvec *rsp, int *buftype,
                         struct cifs_sb_info *cifs_sb)
{
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = cifs_pick_channel(ses);
        int flags = CIFS_CP_CREATE_CLOSE_OP;
        struct smb_rqst rqst[3];
        int resp_buftype[3];
        struct kvec rsp_iov[3];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec qi_iov[1];
        struct kvec close_iov[1];
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        int rc;

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        oparms.tcon = tcon;
        oparms.desired_access = desired_access;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, utf16_path);
        if (rc)
                goto qic_exit;
        smb2_set_next_command(tcon, &rqst[0]);

        memset(&qi_iov, 0, sizeof(qi_iov));
        rqst[1].rq_iov = qi_iov;
        rqst[1].rq_nvec = 1;

        rc = SMB2_query_info_init(tcon, server,
                                  &rqst[1], COMPOUND_FID, COMPOUND_FID,
                                  class, type, 0,
                                  output_len, 0,
                                  NULL);
        if (rc)
                goto qic_exit;
        smb2_set_next_command(tcon, &rqst[1]);
        smb2_set_related(&rqst[1]);

        memset(&close_iov, 0, sizeof(close_iov));
        rqst[2].rq_iov = close_iov;
        rqst[2].rq_nvec = 1;

        rc = SMB2_close_init(tcon, server,
                             &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
        if (rc)
                goto qic_exit;
        smb2_set_related(&rqst[2]);

        rc = compound_send_recv(xid, ses, server,
                                flags, 3, rqst,
                                resp_buftype, rsp_iov);
        if (rc) {
                free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
                if (rc == -EREMCHG) {
                        tcon->need_reconnect = true;
                        pr_warn_once("server share %s deleted\n",
                                     tcon->treeName);
                }
                goto qic_exit;
        }
        *rsp = rsp_iov[1];
        *buftype = resp_buftype[1];

 qic_exit:
        SMB2_open_free(&rqst[0]);
        SMB2_query_info_free(&rqst[1]);
        SMB2_close_free(&rqst[2]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
        return rc;
}

static int
smb2_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
             struct cifs_sb_info *cifs_sb, struct kstatfs *buf)
{
        struct smb2_query_info_rsp *rsp;
        struct smb2_fs_full_size_info *info = NULL;
        __le16 utf16_path = 0; /* Null - open root of share */
        struct kvec rsp_iov = {NULL, 0};
        int buftype = CIFS_NO_BUFFER;
        int rc;


        rc = smb2_query_info_compound(xid, tcon, &utf16_path,
                                      FILE_READ_ATTRIBUTES,
                                      FS_FULL_SIZE_INFORMATION,
                                      SMB2_O_INFO_FILESYSTEM,
                                      sizeof(struct smb2_fs_full_size_info),
                                      &rsp_iov, &buftype, cifs_sb);
        if (rc)
                goto qfs_exit;

        rsp = (struct smb2_query_info_rsp *)rsp_iov.iov_base;
        buf->f_type = SMB2_MAGIC_NUMBER;
        info = (struct smb2_fs_full_size_info *)(
                le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
        rc = smb2_validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
                               le32_to_cpu(rsp->OutputBufferLength),
                               &rsp_iov,
                               sizeof(struct smb2_fs_full_size_info));
        if (!rc)
                smb2_copy_fs_info_to_kstatfs(info, buf);

qfs_exit:
        free_rsp_buf(buftype, rsp_iov.iov_base);
        return rc;
}

static int
smb311_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
               struct cifs_sb_info *cifs_sb, struct kstatfs *buf)
{
        int rc;
        __le16 srch_path = 0; /* Null - open root of share */
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;

        if (!tcon->posix_extensions)
                return smb2_queryfs(xid, tcon, cifs_sb, buf);

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, &srch_path, &oplock, NULL, NULL,
                       NULL, NULL);
        if (rc)
                return rc;

        rc = SMB311_posix_qfs_info(xid, tcon, fid.persistent_fid,
                                   fid.volatile_fid, buf);
        buf->f_type = SMB2_MAGIC_NUMBER;
        SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        return rc;
}

static bool
smb2_compare_fids(struct cifsFileInfo *ob1, struct cifsFileInfo *ob2)
{
        return ob1->fid.persistent_fid == ob2->fid.persistent_fid &&
               ob1->fid.volatile_fid == ob2->fid.volatile_fid;
}

static int
smb2_mand_lock(const unsigned int xid, struct cifsFileInfo *cfile, __u64 offset,
               __u64 length, __u32 type, int lock, int unlock, bool wait)
{
        if (unlock && !lock)
                type = SMB2_LOCKFLAG_UNLOCK;
        return SMB2_lock(xid, tlink_tcon(cfile->tlink),
                         cfile->fid.persistent_fid, cfile->fid.volatile_fid,
                         current->tgid, length, offset, type, wait);
}

static void
smb2_get_lease_key(struct inode *inode, struct cifs_fid *fid)
{
        memcpy(fid->lease_key, CIFS_I(inode)->lease_key, SMB2_LEASE_KEY_SIZE);
}

static void
smb2_set_lease_key(struct inode *inode, struct cifs_fid *fid)
{
        memcpy(CIFS_I(inode)->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);
}

static void
smb2_new_lease_key(struct cifs_fid *fid)
{
        generate_random_uuid(fid->lease_key);
}

static int
smb2_get_dfs_refer(const unsigned int xid, struct cifs_ses *ses,
                   const char *search_name,
                   struct dfs_info3_param **target_nodes,
                   unsigned int *num_of_nodes,
                   const struct nls_table *nls_codepage, int remap)
{
        int rc;
        __le16 *utf16_path = NULL;
        int utf16_path_len = 0;
        struct cifs_tcon *tcon;
        struct fsctl_get_dfs_referral_req *dfs_req = NULL;
        struct get_dfs_referral_rsp *dfs_rsp = NULL;
        u32 dfs_req_size = 0, dfs_rsp_size = 0;

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

        /*
         * Try to use the IPC tcon, otherwise just use any
         */
        tcon = ses->tcon_ipc;
        if (tcon == NULL) {
                spin_lock(&cifs_tcp_ses_lock);
                tcon = list_first_entry_or_null(&ses->tcon_list,
                                                struct cifs_tcon,
                                                tcon_list);
                if (tcon)
                        tcon->tc_count++;
                spin_unlock(&cifs_tcp_ses_lock);
        }

        if (tcon == NULL) {
                cifs_dbg(VFS, "session %p has no tcon available for a dfs referral request\n",
                         ses);
                rc = -ENOTCONN;
                goto out;
        }

        utf16_path = cifs_strndup_to_utf16(search_name, PATH_MAX,
                                           &utf16_path_len,
                                           nls_codepage, remap);
        if (!utf16_path) {
                rc = -ENOMEM;
                goto out;
        }

        dfs_req_size = sizeof(*dfs_req) + utf16_path_len;
        dfs_req = kzalloc(dfs_req_size, GFP_KERNEL);
        if (!dfs_req) {
                rc = -ENOMEM;
                goto out;
        }

        /* Highest DFS referral version understood */
        dfs_req->MaxReferralLevel = DFS_VERSION;

        /* Path to resolve in an UTF-16 null-terminated string */
        memcpy(dfs_req->RequestFileName, utf16_path, utf16_path_len);

        do {
                rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
                                FSCTL_DFS_GET_REFERRALS,
                                true /* is_fsctl */,
                                (char *)dfs_req, dfs_req_size, CIFSMaxBufSize,
                                (char **)&dfs_rsp, &dfs_rsp_size);
        } while (rc == -EAGAIN);

        if (rc) {
                if ((rc != -ENOENT) && (rc != -EOPNOTSUPP))
                        cifs_tcon_dbg(VFS, "ioctl error in %s rc=%d\n", __func__, rc);
                goto out;
        }

        rc = parse_dfs_referrals(dfs_rsp, dfs_rsp_size,
                                 num_of_nodes, target_nodes,
                                 nls_codepage, remap, search_name,
                                 true /* is_unicode */);
        if (rc) {
                cifs_tcon_dbg(VFS, "parse error in %s rc=%d\n", __func__, rc);
                goto out;
        }

 out:
        if (tcon && !tcon->ipc) {
                /* ipc tcons are not refcounted */
                spin_lock(&cifs_tcp_ses_lock);
                tcon->tc_count--;
                /* tc_count can never go negative */
                WARN_ON(tcon->tc_count < 0);
                spin_unlock(&cifs_tcp_ses_lock);
        }
        kfree(utf16_path);
        kfree(dfs_req);
        kfree(dfs_rsp);
        return rc;
}

static int
parse_reparse_posix(struct reparse_posix_data *symlink_buf,
                      u32 plen, char **target_path,
                      struct cifs_sb_info *cifs_sb)
{
        unsigned int len;

        /* See MS-FSCC 2.1.2.6 for the 'NFS' style reparse tags */
        len = le16_to_cpu(symlink_buf->ReparseDataLength);

        if (le64_to_cpu(symlink_buf->InodeType) != NFS_SPECFILE_LNK) {
                cifs_dbg(VFS, "%lld not a supported symlink type\n",
                        le64_to_cpu(symlink_buf->InodeType));
                return -EOPNOTSUPP;
        }

        *target_path = cifs_strndup_from_utf16(
                                symlink_buf->PathBuffer,
                                len, true, cifs_sb->local_nls);
        if (!(*target_path))
                return -ENOMEM;

        convert_delimiter(*target_path, '/');
        cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);

        return 0;
}

static int
parse_reparse_symlink(struct reparse_symlink_data_buffer *symlink_buf,
                      u32 plen, char **target_path,
                      struct cifs_sb_info *cifs_sb)
{
        unsigned int sub_len;
        unsigned int sub_offset;

        /* We handle Symbolic Link reparse tag here. See: MS-FSCC 2.1.2.4 */

        sub_offset = le16_to_cpu(symlink_buf->SubstituteNameOffset);
        sub_len = le16_to_cpu(symlink_buf->SubstituteNameLength);
        if (sub_offset + 20 > plen ||
            sub_offset + sub_len + 20 > plen) {
                cifs_dbg(VFS, "srv returned malformed symlink buffer\n");
                return -EIO;
        }

        *target_path = cifs_strndup_from_utf16(
                                symlink_buf->PathBuffer + sub_offset,
                                sub_len, true, cifs_sb->local_nls);
        if (!(*target_path))
                return -ENOMEM;

        convert_delimiter(*target_path, '/');
        cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);

        return 0;
}

static int
parse_reparse_point(struct reparse_data_buffer *buf,
                    u32 plen, char **target_path,
                    struct cifs_sb_info *cifs_sb)
{
        if (plen < sizeof(struct reparse_data_buffer)) {
                cifs_dbg(VFS, "reparse buffer is too small. Must be at least 8 bytes but was %d\n",
                         plen);
                return -EIO;
        }

        if (plen < le16_to_cpu(buf->ReparseDataLength) +
            sizeof(struct reparse_data_buffer)) {
                cifs_dbg(VFS, "srv returned invalid reparse buf length: %d\n",