From b8c32dbb0deb287a5fcb78251e4eae6c7275760d Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Wed, 19 Sep 2012 06:22:44 -0700 Subject: [PATCH] CIFS: Request SMB2.1 leases if server supports them and we need oplocks. Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French --- fs/cifs/cifsfs.c | 28 ++++++--- fs/cifs/cifsglob.h | 10 ++++ fs/cifs/dir.c | 13 ++++- fs/cifs/file.c | 21 +++++-- fs/cifs/smb2file.c | 9 ++- fs/cifs/smb2ops.c | 21 +++++++ fs/cifs/smb2pdu.c | 138 ++++++++++++++++++++++++++++++++++++++++++--- fs/cifs/smb2pdu.h | 43 +++++++++++++- 8 files changed, 256 insertions(+), 27 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 4cd68c77ce39c5..28ac048d54ea1a 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include "cifsfs.h" #include "cifspdu.h" @@ -88,6 +89,10 @@ extern mempool_t *cifs_mid_poolp; struct workqueue_struct *cifsiod_wq; +#ifdef CONFIG_CIFS_SMB2 +__u8 cifs_client_guid[SMB2_CLIENT_GUID_SIZE]; +#endif + static int cifs_read_super(struct super_block *sb) { @@ -218,9 +223,10 @@ cifs_alloc_inode(struct super_block *sb) return NULL; cifs_inode->cifsAttrs = 0x20; /* default */ cifs_inode->time = 0; - /* Until the file is open and we have gotten oplock - info back from the server, can not assume caching of - file data or metadata */ + /* + * Until the file is open and we have gotten oplock info back from the + * server, can not assume caching of file data or metadata. + */ cifs_set_oplock_level(cifs_inode, 0); cifs_inode->delete_pending = false; cifs_inode->invalid_mapping = false; @@ -228,10 +234,14 @@ cifs_alloc_inode(struct super_block *sb) cifs_inode->server_eof = 0; cifs_inode->uniqueid = 0; cifs_inode->createtime = 0; - - /* Can not set i_flags here - they get immediately overwritten - to zero by the VFS */ -/* cifs_inode->vfs_inode.i_flags = S_NOATIME | S_NOCMTIME;*/ +#ifdef CONFIG_CIFS_SMB2 + get_random_bytes(cifs_inode->lease_key, SMB2_LEASE_KEY_SIZE); +#endif + /* + * Can not set i_flags here - they get immediately overwritten to zero + * by the VFS. + */ + /* cifs_inode->vfs_inode.i_flags = S_NOATIME | S_NOCMTIME; */ INIT_LIST_HEAD(&cifs_inode->openFileList); INIT_LIST_HEAD(&cifs_inode->llist); return &cifs_inode->vfs_inode; @@ -1107,6 +1117,10 @@ init_cifs(void) spin_lock_init(&cifs_file_list_lock); spin_lock_init(&GlobalMid_Lock); +#ifdef CONFIG_CIFS_SMB2 + get_random_bytes(cifs_client_guid, SMB2_CLIENT_GUID_SIZE); +#endif + if (cifs_max_pending < 2) { cifs_max_pending = 2; cFYI(1, "cifs_max_pending set to min of 2"); diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index e2492e1cdb8555..b6ec142028e8f6 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -361,6 +361,12 @@ struct smb_version_operations { const unsigned int); /* push brlocks from the cache to the server */ int (*push_mand_locks)(struct cifsFileInfo *); + /* get lease key of the inode */ + void (*get_lease_key)(struct inode *, struct cifs_fid *fid); + /* set lease key of the inode */ + void (*set_lease_key)(struct inode *, struct cifs_fid *fid); + /* generate new lease key */ + void (*new_lease_key)(struct cifs_fid *fid); }; struct smb_version_values { @@ -895,6 +901,7 @@ struct cifs_fid { #ifdef CONFIG_CIFS_SMB2 __u64 persistent_fid; /* persist file id for smb2 */ __u64 volatile_fid; /* volatile file id for smb2 */ + __u8 lease_key[SMB2_LEASE_KEY_SIZE]; /* lease key for smb2 */ #endif }; @@ -1012,6 +1019,9 @@ struct cifsInodeInfo { u64 server_eof; /* current file size on server -- protected by i_lock */ u64 uniqueid; /* server inode number */ u64 createtime; /* creation time on server */ +#ifdef CONFIG_CIFS_SMB2 + __u8 lease_key[SMB2_LEASE_KEY_SIZE]; /* lease key for this inode */ +#endif #ifdef CONFIG_CIFS_FSCACHE struct fscache_cookie *fscache; #endif diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c index b99a1670dad416..4f2147c5adb60d 100644 --- a/fs/cifs/dir.c +++ b/fs/cifs/dir.c @@ -340,6 +340,8 @@ cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid, rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb, xid, &fid->netfid); if (newinode) { + if (server->ops->set_lease_key) + server->ops->set_lease_key(newinode, fid); if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM) newinode->i_mode = mode; if ((*oplock & CIFS_CREATE_ACTION) && @@ -418,6 +420,9 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry, tcon = tlink_tcon(tlink); server = tcon->ses->server; + if (server->ops->new_lease_key) + server->ops->new_lease_key(&fid); + rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, opened); @@ -473,10 +478,14 @@ int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode, if (IS_ERR(tlink)) goto out_free_xid; - rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, - &oplock, &fid, &created); tcon = tlink_tcon(tlink); server = tcon->ses->server; + + if (server->ops->new_lease_key) + server->ops->new_lease_key(&fid); + + rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, + &oplock, &fid, &created); if (!rc && server->ops->close) server->ops->close(xid, tcon, &fid); diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 2e2e4f9aeb6347..ccad858d2d67f9 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -177,8 +177,9 @@ cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb, int disposition; int create_options = CREATE_NOT_DIR; FILE_ALL_INFO *buf; + struct TCP_Server_Info *server = tcon->ses->server; - if (!tcon->ses->server->ops->open) + if (!server->ops->open) return -ENOSYS; desired_access = cifs_convert_flags(f_flags); @@ -218,9 +219,9 @@ cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb, if (backup_cred(cifs_sb)) create_options |= CREATE_OPEN_BACKUP_INTENT; - rc = tcon->ses->server->ops->open(xid, tcon, full_path, disposition, - desired_access, create_options, fid, - oplock, buf, cifs_sb); + rc = server->ops->open(xid, tcon, full_path, disposition, + desired_access, create_options, fid, oplock, buf, + cifs_sb); if (rc) goto out; @@ -372,6 +373,7 @@ int cifs_open(struct inode *inode, struct file *file) unsigned int xid; __u32 oplock; struct cifs_sb_info *cifs_sb; + struct TCP_Server_Info *server; struct cifs_tcon *tcon; struct tcon_link *tlink; struct cifsFileInfo *cfile = NULL; @@ -388,6 +390,7 @@ int cifs_open(struct inode *inode, struct file *file) return PTR_ERR(tlink); } tcon = tlink_tcon(tlink); + server = tcon->ses->server; full_path = build_path_from_dentry(file->f_path.dentry); if (full_path == NULL) { @@ -432,6 +435,9 @@ int cifs_open(struct inode *inode, struct file *file) } if (!posix_open_ok) { + if (server->ops->get_lease_key) + server->ops->get_lease_key(inode, &fid); + rc = cifs_nt_open(full_path, inode, cifs_sb, tcon, file->f_flags, &oplock, &fid, xid); if (rc) @@ -440,8 +446,8 @@ int cifs_open(struct inode *inode, struct file *file) cfile = cifs_new_fileinfo(&fid, file, tlink, oplock); if (cfile == NULL) { - if (tcon->ses->server->ops->close) - tcon->ses->server->ops->close(xid, tcon, &fid); + if (server->ops->close) + server->ops->close(xid, tcon, &fid); rc = -ENOMEM; goto out; } @@ -567,6 +573,9 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush) if (backup_cred(cifs_sb)) create_options |= CREATE_OPEN_BACKUP_INTENT; + if (server->ops->get_lease_key) + server->ops->get_lease_key(inode, &fid); + /* * Can not refresh inode by passing in file_info buf to be returned by * CIFSSMBOpen and then calling get_inode_info with returned buf since diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c index 0ddd617ffa1a7c..78fb2050e0d6e7 100644 --- a/fs/cifs/smb2file.c +++ b/fs/cifs/smb2file.c @@ -63,6 +63,7 @@ smb2_open_file(const unsigned int xid, struct cifs_tcon *tcon, const char *path, int rc; __le16 *smb2_path; struct smb2_file_all_info *smb2_data = NULL; + __u8 smb2_oplock[17]; smb2_path = cifs_convert_path_to_utf16(path, cifs_sb); if (smb2_path == NULL) { @@ -78,11 +79,14 @@ smb2_open_file(const unsigned int xid, struct cifs_tcon *tcon, const char *path, } desired_access |= FILE_READ_ATTRIBUTES; - *oplock = SMB2_OPLOCK_LEVEL_EXCLUSIVE; + *smb2_oplock = SMB2_OPLOCK_LEVEL_EXCLUSIVE; + + if (tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING) + memcpy(smb2_oplock + 1, fid->lease_key, SMB2_LEASE_KEY_SIZE); rc = SMB2_open(xid, tcon, smb2_path, &fid->persistent_fid, &fid->volatile_fid, desired_access, disposition, - 0, 0, (__u8 *)oplock, smb2_data); + 0, 0, smb2_oplock, smb2_data); if (rc) goto out; @@ -99,6 +103,7 @@ smb2_open_file(const unsigned int xid, struct cifs_tcon *tcon, const char *path, move_smb2_info_to_cifs(buf, smb2_data); } + *oplock = *smb2_oplock; out: kfree(smb2_data); kfree(smb2_path); diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 0808b238219b08..360d9079af4992 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -555,6 +555,24 @@ smb2_mand_lock(const unsigned int xid, struct cifsFileInfo *cfile, __u64 offset, 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) +{ + get_random_bytes(fid->lease_key, SMB2_LEASE_KEY_SIZE); +} + struct smb_version_operations smb21_operations = { .compare_fids = smb2_compare_fids, .setup_request = smb2_setup_request, @@ -616,6 +634,9 @@ struct smb_version_operations smb21_operations = { .mand_lock = smb2_mand_lock, .mand_unlock_range = smb2_unlock_range, .push_mand_locks = smb2_push_mandatory_locks, + .get_lease_key = smb2_get_lease_key, + .set_lease_key = smb2_set_lease_key, + .new_lease_key = smb2_new_lease_key, }; struct smb_version_values smb21_values = { diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index d3e1cfca3379a5..89d2824587b2be 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -304,7 +304,7 @@ free_rsp_buf(int resp_buftype, void *rsp) cifs_buf_release(rsp); } -#define SMB2_NUM_PROT 1 +#define SMB2_NUM_PROT 2 #define SMB2_PROT 0 #define SMB21_PROT 1 @@ -393,6 +393,8 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) req->Capabilities = cpu_to_le32(SMB2_GLOBAL_CAP_DFS); + memcpy(req->ClientGUID, cifs_client_guid, SMB2_CLIENT_GUID_SIZE); + iov[0].iov_base = (char *)req; /* 4 for rfc1002 length field */ iov[0].iov_len = get_rfc1002_length(req) + 4; @@ -868,6 +870,83 @@ SMB2_tdis(const unsigned int xid, struct cifs_tcon *tcon) return rc; } +static struct create_lease * +create_lease_buf(u8 *lease_key, u8 oplock) +{ + struct create_lease *buf; + + buf = kmalloc(sizeof(struct create_lease), GFP_KERNEL); + if (!buf) + return NULL; + + memset(buf, 0, sizeof(struct create_lease)); + + buf->lcontext.LeaseKeyLow = cpu_to_le64(*((u64 *)lease_key)); + buf->lcontext.LeaseKeyHigh = cpu_to_le64(*((u64 *)(lease_key + 8))); + if (oplock == SMB2_OPLOCK_LEVEL_EXCLUSIVE) + buf->lcontext.LeaseState = SMB2_LEASE_WRITE_CACHING | + SMB2_LEASE_READ_CACHING; + else if (oplock == SMB2_OPLOCK_LEVEL_II) + buf->lcontext.LeaseState = SMB2_LEASE_READ_CACHING; + else if (oplock == SMB2_OPLOCK_LEVEL_BATCH) + buf->lcontext.LeaseState = SMB2_LEASE_HANDLE_CACHING | + SMB2_LEASE_READ_CACHING | + SMB2_LEASE_WRITE_CACHING; + + buf->ccontext.DataOffset = cpu_to_le16(offsetof + (struct create_lease, lcontext)); + buf->ccontext.DataLength = cpu_to_le32(sizeof(struct lease_context)); + buf->ccontext.NameOffset = cpu_to_le16(offsetof + (struct create_lease, Name)); + buf->ccontext.NameLength = cpu_to_le16(4); + buf->Name[0] = 'R'; + buf->Name[1] = 'q'; + buf->Name[2] = 'L'; + buf->Name[3] = 's'; + return buf; +} + +static __u8 +parse_lease_state(struct smb2_create_rsp *rsp) +{ + char *data_offset; + struct create_lease *lc; + __u8 oplock = 0; + bool found = false; + + data_offset = (char *)rsp; + data_offset += 4 + le32_to_cpu(rsp->CreateContextsOffset); + lc = (struct create_lease *)data_offset; + do { + char *name = le16_to_cpu(lc->ccontext.NameOffset) + (char *)lc; + if (le16_to_cpu(lc->ccontext.NameLength) != 4 || + strncmp(name, "RqLs", 4)) { + lc = (struct create_lease *)((char *)lc + + le32_to_cpu(lc->ccontext.Next)); + continue; + } + if (lc->lcontext.LeaseFlags & SMB2_LEASE_FLAG_BREAK_IN_PROGRESS) + return SMB2_OPLOCK_LEVEL_NOCHANGE; + found = true; + break; + } while (le32_to_cpu(lc->ccontext.Next) != 0); + + if (!found) + return oplock; + + if (le32_to_cpu(lc->lcontext.LeaseState) & SMB2_LEASE_WRITE_CACHING) { + if (le32_to_cpu(lc->lcontext.LeaseState) & + SMB2_LEASE_HANDLE_CACHING) + oplock = SMB2_OPLOCK_LEVEL_BATCH; + else + oplock = SMB2_OPLOCK_LEVEL_EXCLUSIVE; + } else if (le32_to_cpu(lc->lcontext.LeaseState) & + SMB2_LEASE_READ_CACHING) + oplock = SMB2_OPLOCK_LEVEL_II; + + return oplock; +} + int SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path, u64 *persistent_fid, u64 *volatile_fid, __u32 desired_access, @@ -878,9 +957,11 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path, struct smb2_create_rsp *rsp; struct TCP_Server_Info *server; struct cifs_ses *ses = tcon->ses; - struct kvec iov[2]; + struct kvec iov[3]; int resp_buftype; int uni_path_len; + __le16 *copy_path = NULL; + int copy_size; int rc = 0; int num_iovecs = 2; @@ -895,10 +976,6 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path, if (rc) return rc; - if (server->oplocks) - req->RequestedOplockLevel = *oplock; - else - req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_NONE; req->ImpersonationLevel = IL_IMPERSONATION; req->DesiredAccess = cpu_to_le32(desired_access); /* File attributes ignored on open (used in create though) */ @@ -908,7 +985,7 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path, req->CreateOptions = cpu_to_le32(create_options); uni_path_len = (2 * UniStrnlen((wchar_t *)path, PATH_MAX)) + 2; req->NameOffset = cpu_to_le16(sizeof(struct smb2_create_req) - - 1 /* pad */ - 4 /* do not count rfc1001 len field */); + - 8 /* pad */ - 4 /* do not count rfc1001 len field */); iov[0].iov_base = (char *)req; /* 4 for rfc1002 length field */ @@ -919,6 +996,20 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path, req->NameLength = cpu_to_le16(uni_path_len - 2); /* -1 since last byte is buf[0] which is sent below (path) */ iov[0].iov_len--; + if (uni_path_len % 8 != 0) { + copy_size = uni_path_len / 8 * 8; + if (copy_size < uni_path_len) + copy_size += 8; + + copy_path = kzalloc(copy_size, GFP_KERNEL); + if (!copy_path) + return -ENOMEM; + memcpy((char *)copy_path, (const char *)path, + uni_path_len); + uni_path_len = copy_size; + path = copy_path; + } + iov[1].iov_len = uni_path_len; iov[1].iov_base = path; /* @@ -927,10 +1018,37 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path, */ inc_rfc1001_len(req, uni_path_len - 1); } else { + iov[0].iov_len += 7; + req->hdr.smb2_buf_length = cpu_to_be32(be32_to_cpu( + req->hdr.smb2_buf_length) + 8 - 1); num_iovecs = 1; req->NameLength = 0; } + if (!server->oplocks) + *oplock = SMB2_OPLOCK_LEVEL_NONE; + + if (!(tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING) || + *oplock == SMB2_OPLOCK_LEVEL_NONE) + req->RequestedOplockLevel = *oplock; + else { + iov[num_iovecs].iov_base = create_lease_buf(oplock+1, *oplock); + if (iov[num_iovecs].iov_base == NULL) { + cifs_small_buf_release(req); + kfree(copy_path); + return -ENOMEM; + } + iov[num_iovecs].iov_len = sizeof(struct create_lease); + req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_LEASE; + req->CreateContextsOffset = cpu_to_le32( + sizeof(struct smb2_create_req) - 4 - 8 + + iov[num_iovecs-1].iov_len); + req->CreateContextsLength = cpu_to_le32( + sizeof(struct create_lease)); + inc_rfc1001_len(&req->hdr, sizeof(struct create_lease)); + num_iovecs++; + } + rc = SendReceive2(xid, ses, iov, num_iovecs, &resp_buftype, 0); rsp = (struct smb2_create_rsp *)iov[0].iov_base; @@ -955,8 +1073,12 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path, buf->DeletePending = 0; } - *oplock = rsp->OplockLevel; + if (rsp->OplockLevel == SMB2_OPLOCK_LEVEL_LEASE) + *oplock = parse_lease_state(rsp); + else + *oplock = rsp->OplockLevel; creat_exit: + kfree(copy_path); free_rsp_buf(resp_buftype, rsp); return rc; } diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 889ee5e193d9e3..e818a5cc5bd8c8 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -150,6 +150,10 @@ struct smb2_err_rsp { __u8 ErrorData[1]; /* variable length */ } __packed; +#define SMB2_CLIENT_GUID_SIZE 16 + +extern __u8 cifs_client_guid[SMB2_CLIENT_GUID_SIZE]; + struct smb2_negotiate_req { struct smb2_hdr hdr; __le16 StructureSize; /* Must be 36 */ @@ -157,7 +161,7 @@ struct smb2_negotiate_req { __le16 SecurityMode; __le16 Reserved; /* MBZ */ __le32 Capabilities; - __u8 ClientGUID[16]; /* MBZ */ + __u8 ClientGUID[SMB2_CLIENT_GUID_SIZE]; __le64 ClientStartTime; /* MBZ */ __le16 Dialects[2]; /* variable length */ } __packed; @@ -307,6 +311,8 @@ struct smb2_tree_disconnect_rsp { #define SMB2_OPLOCK_LEVEL_EXCLUSIVE 0x08 #define SMB2_OPLOCK_LEVEL_BATCH 0x09 #define SMB2_OPLOCK_LEVEL_LEASE 0xFF +/* Non-spec internal type */ +#define SMB2_OPLOCK_LEVEL_NOCHANGE 0x99 /* Desired Access Flags */ #define FILE_READ_DATA_LE cpu_to_le32(0x00000001) @@ -404,7 +410,7 @@ struct smb2_create_req { __le16 NameLength; __le32 CreateContextsOffset; __le32 CreateContextsLength; - __u8 Buffer[1]; + __u8 Buffer[8]; } __packed; struct smb2_create_rsp { @@ -428,6 +434,39 @@ struct smb2_create_rsp { __u8 Buffer[1]; } __packed; +struct create_context { + __le32 Next; + __le16 NameOffset; + __le16 NameLength; + __le16 Reserved; + __le16 DataOffset; + __le32 DataLength; + __u8 Buffer[0]; +} __packed; + +#define SMB2_LEASE_NONE __constant_cpu_to_le32(0x00) +#define SMB2_LEASE_READ_CACHING __constant_cpu_to_le32(0x01) +#define SMB2_LEASE_HANDLE_CACHING __constant_cpu_to_le32(0x02) +#define SMB2_LEASE_WRITE_CACHING __constant_cpu_to_le32(0x04) + +#define SMB2_LEASE_FLAG_BREAK_IN_PROGRESS __constant_cpu_to_le32(0x02) + +#define SMB2_LEASE_KEY_SIZE 16 + +struct lease_context { + __le64 LeaseKeyLow; + __le64 LeaseKeyHigh; + __le32 LeaseState; + __le32 LeaseFlags; + __le64 LeaseDuration; +} __packed; + +struct create_lease { + struct create_context ccontext; + __u8 Name[8]; + struct lease_context lcontext; +} __packed; + /* Currently defined values for close flags */ #define SMB2_CLOSE_FLAG_POSTQUERY_ATTRIB cpu_to_le16(0x0001) struct smb2_close_req {