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Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6

Browse Source 
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: trivial white space
  [CIFS] checkpatch cleanup
  cifs: add cifs_revalidate_file
  cifs: add a CIFSSMBUnixQFileInfo function
  cifs: add a CIFSSMBQFileInfo function
  cifs: overhaul cifs_revalidate and rename to cifs_revalidate_dentry
This commit is contained in:
Linus Torvalds 2010-03-19 09:36:18 -07:00
commit 0a492fdef8
8 changed files with 334 additions and 122 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
fs/cifs/cifsfs.c
View File

@ -312,6 +312,7 @@ cifs_alloc_inode(struct super_block *sb)
cifs_inode->clientCanCacheRead = false;
cifs_inode->clientCanCacheAll = false;
cifs_inode->delete_pending = false;
cifs_inode->invalid_mapping = false;
cifs_inode->vfs_inode.i_blkbits = 14; /* 2**14 = CIFS_MAX_MSGSIZE */
cifs_inode->server_eof = 0;
@ -638,7 +639,7 @@ static loff_t cifs_llseek(struct file *file, loff_t offset, int origin)
setting the revalidate time to zero */
CIFS_I(file->f_path.dentry->d_inode)->time = 0;
retval = cifs_revalidate(file->f_path.dentry);
retval = cifs_revalidate_file(file);
if (retval < 0)
return (loff_t)retval;
}

3
fs/cifs/cifsfs.h
View File

@ -61,7 +61,8 @@ extern int cifs_mkdir(struct inode *, struct dentry *, int);
extern int cifs_rmdir(struct inode *, struct dentry *);
extern int cifs_rename(struct inode *, struct dentry *, struct inode *,
struct dentry *);
extern int cifs_revalidate(struct dentry *);
extern int cifs_revalidate_file(struct file *filp);
extern int cifs_revalidate_dentry(struct dentry *);
extern int cifs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
extern int cifs_setattr(struct dentry *, struct iattr *);

1
fs/cifs/cifsglob.h
View File

@ -389,6 +389,7 @@ struct cifsInodeInfo {
bool clientCanCacheRead:1; /* read oplock */
bool clientCanCacheAll:1; /* read and writebehind oplock */
bool delete_pending:1; /* DELETE_ON_CLOSE is set */
bool invalid_mapping:1; /* pagecache is invalid */
u64 server_eof; /* current file size on server */
u64 uniqueid; /* server inode number */
struct inode vfs_inode;

6
fs/cifs/cifsproto.h
View File

@ -104,10 +104,12 @@ extern void cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr);
extern struct inode *cifs_iget(struct super_block *sb,
struct cifs_fattr *fattr);
extern int cifs_get_file_info(struct file *filp);
extern int cifs_get_inode_info(struct inode **pinode,
const unsigned char *search_path,
FILE_ALL_INFO *pfile_info,
struct super_block *sb, int xid, const __u16 *pfid);
extern int cifs_get_file_info_unix(struct file *filp);
extern int cifs_get_inode_info_unix(struct inode **pinode,
const unsigned char *search_path,
struct super_block *sb, int xid);
@ -142,6 +144,8 @@ extern int CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
extern int CIFSFindClose(const int, struct cifsTconInfo *tcon,
const __u16 search_handle);
extern int CIFSSMBQFileInfo(const int xid, struct cifsTconInfo *tcon,
u16 netfid, FILE_ALL_INFO *pFindData);
extern int CIFSSMBQPathInfo(const int xid, struct cifsTconInfo *tcon,
const unsigned char *searchName,
FILE_ALL_INFO *findData,
@ -152,6 +156,8 @@ extern int SMBQueryInformation(const int xid, struct cifsTconInfo *tcon,
FILE_ALL_INFO *findData,
const struct nls_table *nls_codepage, int remap);
extern int CIFSSMBUnixQFileInfo(const int xid, struct cifsTconInfo *tcon,
u16 netfid, FILE_UNIX_BASIC_INFO *pFindData);
extern int CIFSSMBUnixQPathInfo(const int xid,
struct cifsTconInfo *tcon,
const unsigned char *searchName,

135
fs/cifs/cifssmb.c
View File

@ -500,7 +500,7 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
} else if (pSMBr->hdr.WordCount == 13) {
cERROR(1, ("mount failed, cifs module not built "
"with CIFS_WEAK_PW_HASH support"));
rc = -EOPNOTSUPP;
rc = -EOPNOTSUPP;
#endif /* WEAK_PW_HASH */
goto neg_err_exit;
} else if (pSMBr->hdr.WordCount != 17) {
@ -3230,8 +3230,72 @@ QInfRetry:
return rc;
}
int
CIFSSMBQFileInfo(const int xid, struct cifsTconInfo *tcon,
u16 netfid, FILE_ALL_INFO *pFindData)
{
struct smb_t2_qfi_req *pSMB = NULL;
struct smb_t2_qfi_rsp *pSMBr = NULL;
int rc = 0;
int bytes_returned;
__u16 params, byte_count;
QFileInfoRetry:
rc = smb_init(SMB_COM_TRANSACTION2, 15, tcon, (void **) &pSMB,
(void **) &pSMBr);
if (rc)
return rc;
params = 2 /* level */ + 2 /* fid */;
pSMB->t2.TotalDataCount = 0;
pSMB->t2.MaxParameterCount = cpu_to_le16(4);
/* BB find exact max data count below from sess structure BB */
pSMB->t2.MaxDataCount = cpu_to_le16(CIFSMaxBufSize);
pSMB->t2.MaxSetupCount = 0;
pSMB->t2.Reserved = 0;
pSMB->t2.Flags = 0;
pSMB->t2.Timeout = 0;
pSMB->t2.Reserved2 = 0;
pSMB->t2.ParameterOffset = cpu_to_le16(offsetof(struct smb_t2_qfi_req,
Fid) - 4);
pSMB->t2.DataCount = 0;
pSMB->t2.DataOffset = 0;
pSMB->t2.SetupCount = 1;
pSMB->t2.Reserved3 = 0;
pSMB->t2.SubCommand = cpu_to_le16(TRANS2_QUERY_FILE_INFORMATION);
byte_count = params + 1 /* pad */ ;
pSMB->t2.TotalParameterCount = cpu_to_le16(params);
pSMB->t2.ParameterCount = pSMB->t2.TotalParameterCount;
pSMB->InformationLevel = cpu_to_le16(SMB_QUERY_FILE_ALL_INFO);
pSMB->Pad = 0;
pSMB->Fid = netfid;
pSMB->hdr.smb_buf_length += byte_count;
rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
(struct smb_hdr *) pSMBr, &bytes_returned, 0);
if (rc) {
cFYI(1, ("Send error in QPathInfo = %d", rc));
} else { /* decode response */
rc = validate_t2((struct smb_t2_rsp *)pSMBr);
if (rc) /* BB add auto retry on EOPNOTSUPP? */
rc = -EIO;
else if (pSMBr->ByteCount < 40)
rc = -EIO; /* bad smb */
else if (pFindData) {
__u16 data_offset = le16_to_cpu(pSMBr->t2.DataOffset);
memcpy((char *) pFindData,
(char *) &pSMBr->hdr.Protocol +
data_offset, sizeof(FILE_ALL_INFO));
} else
rc = -ENOMEM;
}
cifs_buf_release(pSMB);
if (rc == -EAGAIN)
goto QFileInfoRetry;
return rc;
}
int
CIFSSMBQPathInfo(const int xid, struct cifsTconInfo *tcon,
@ -3334,6 +3398,75 @@ QPathInfoRetry:
return rc;
}
int
CIFSSMBUnixQFileInfo(const int xid, struct cifsTconInfo *tcon,
u16 netfid, FILE_UNIX_BASIC_INFO *pFindData)
{
struct smb_t2_qfi_req *pSMB = NULL;
struct smb_t2_qfi_rsp *pSMBr = NULL;
int rc = 0;
int bytes_returned;
__u16 params, byte_count;
UnixQFileInfoRetry:
rc = smb_init(SMB_COM_TRANSACTION2, 15, tcon, (void **) &pSMB,
(void **) &pSMBr);
if (rc)
return rc;
params = 2 /* level */ + 2 /* fid */;
pSMB->t2.TotalDataCount = 0;
pSMB->t2.MaxParameterCount = cpu_to_le16(4);
/* BB find exact max data count below from sess structure BB */
pSMB->t2.MaxDataCount = cpu_to_le16(CIFSMaxBufSize);
pSMB->t2.MaxSetupCount = 0;
pSMB->t2.Reserved = 0;
pSMB->t2.Flags = 0;
pSMB->t2.Timeout = 0;
pSMB->t2.Reserved2 = 0;
pSMB->t2.ParameterOffset = cpu_to_le16(offsetof(struct smb_t2_qfi_req,
Fid) - 4);
pSMB->t2.DataCount = 0;
pSMB->t2.DataOffset = 0;
pSMB->t2.SetupCount = 1;
pSMB->t2.Reserved3 = 0;
pSMB->t2.SubCommand = cpu_to_le16(TRANS2_QUERY_FILE_INFORMATION);
byte_count = params + 1 /* pad */ ;
pSMB->t2.TotalParameterCount = cpu_to_le16(params);
pSMB->t2.ParameterCount = pSMB->t2.TotalParameterCount;
pSMB->InformationLevel = cpu_to_le16(SMB_QUERY_FILE_UNIX_BASIC);
pSMB->Pad = 0;
pSMB->Fid = netfid;
pSMB->hdr.smb_buf_length += byte_count;
rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
(struct smb_hdr *) pSMBr, &bytes_returned, 0);
if (rc) {
cFYI(1, ("Send error in QPathInfo = %d", rc));
} else { /* decode response */
rc = validate_t2((struct smb_t2_rsp *)pSMBr);
if (rc || (pSMBr->ByteCount < sizeof(FILE_UNIX_BASIC_INFO))) {
cERROR(1, ("Malformed FILE_UNIX_BASIC_INFO response.\n"
"Unix Extensions can be disabled on mount "
"by specifying the nosfu mount option."));
rc = -EIO; /* bad smb */
} else {
__u16 data_offset = le16_to_cpu(pSMBr->t2.DataOffset);
memcpy((char *) pFindData,
(char *) &pSMBr->hdr.Protocol +
data_offset,
sizeof(FILE_UNIX_BASIC_INFO));
}
}
cifs_buf_release(pSMB);
if (rc == -EAGAIN)
goto UnixQFileInfoRetry;
return rc;
}
int
CIFSSMBUnixQPathInfo(const int xid, struct cifsTconInfo *tcon,
const unsigned char *searchName,

2
fs/cifs/dir.c
View File

@ -739,7 +739,7 @@ cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd)
int isValid = 1;
if (direntry->d_inode) {
if (cifs_revalidate(direntry))
if (cifs_revalidate_dentry(direntry))
return 0;
} else {
cFYI(1, ("neg dentry 0x%p name = %s",

7
fs/cifs/file.c
View File

@ -219,8 +219,8 @@ static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
cFYI(1, ("inode unchanged on server"));
} else {
if (file->f_path.dentry->d_inode->i_mapping) {
/* BB no need to lock inode until after invalidate
since namei code should already have it locked? */
/* BB no need to lock inode until after invalidate
since namei code should already have it locked? */
rc = filemap_write_and_wait(file->f_path.dentry->d_inode->i_mapping);
if (rc != 0)
CIFS_I(file->f_path.dentry->d_inode)->write_behind_rc = rc;
@ -1890,11 +1890,10 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
struct dentry *dentry = file->f_path.dentry;
int rc, xid;
xid = GetXid();
rc = cifs_revalidate(dentry);
rc = cifs_revalidate_file(file);
if (rc) {
cFYI(1, ("Validation prior to mmap failed, error=%d", rc));
FreeXid(xid);

299
fs/cifs/inode.c
View File

@ -77,6 +77,41 @@ static void cifs_set_ops(struct inode *inode, const bool is_dfs_referral)
}
}
/* check inode attributes against fattr. If they don't match, tag the
* inode for cache invalidation
*/
static void
cifs_revalidate_cache(struct inode *inode, struct cifs_fattr *fattr)
{
struct cifsInodeInfo *cifs_i = CIFS_I(inode);
cFYI(1, ("%s: revalidating inode %llu", __func__, cifs_i->uniqueid));
if (inode->i_state & I_NEW) {
cFYI(1, ("%s: inode %llu is new", __func__, cifs_i->uniqueid));
return;
}
/* don't bother with revalidation if we have an oplock */
if (cifs_i->clientCanCacheRead) {
cFYI(1, ("%s: inode %llu is oplocked", __func__,
cifs_i->uniqueid));
return;
}
/* revalidate if mtime or size have changed */
if (timespec_equal(&inode->i_mtime, &fattr->cf_mtime) &&
cifs_i->server_eof == fattr->cf_eof) {
cFYI(1, ("%s: inode %llu is unchanged", __func__,
cifs_i->uniqueid));
return;
}
cFYI(1, ("%s: invalidating inode %llu mapping", __func__,
cifs_i->uniqueid));
cifs_i->invalid_mapping = true;
}
/* populate an inode with info from a cifs_fattr struct */
void
cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
@ -85,6 +120,8 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
unsigned long oldtime = cifs_i->time;
cifs_revalidate_cache(inode, fattr);
inode->i_atime = fattr->cf_atime;
inode->i_mtime = fattr->cf_mtime;
inode->i_ctime = fattr->cf_ctime;
@ -231,6 +268,31 @@ cifs_create_dfs_fattr(struct cifs_fattr *fattr, struct super_block *sb)
fattr->cf_flags |= CIFS_FATTR_DFS_REFERRAL;
}
int cifs_get_file_info_unix(struct file *filp)
{
int rc;
int xid;
FILE_UNIX_BASIC_INFO find_data;
struct cifs_fattr fattr;
struct inode *inode = filp->f_path.dentry->d_inode;
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
struct cifsTconInfo *tcon = cifs_sb->tcon;
struct cifsFileInfo *cfile = (struct cifsFileInfo *) filp->private_data;
xid = GetXid();
rc = CIFSSMBUnixQFileInfo(xid, tcon, cfile->netfid, &find_data);
if (!rc) {
cifs_unix_basic_to_fattr(&fattr, &find_data, cifs_sb);
} else if (rc == -EREMOTE) {
cifs_create_dfs_fattr(&fattr, inode->i_sb);
rc = 0;
}
cifs_fattr_to_inode(inode, &fattr);
FreeXid(xid);
return rc;
}
int cifs_get_inode_info_unix(struct inode **pinode,
const unsigned char *full_path,
struct super_block *sb, int xid)
@ -432,6 +494,47 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
fattr->cf_gid = cifs_sb->mnt_gid;
}
int cifs_get_file_info(struct file *filp)
{
int rc;
int xid;
FILE_ALL_INFO find_data;
struct cifs_fattr fattr;
struct inode *inode = filp->f_path.dentry->d_inode;
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
struct cifsTconInfo *tcon = cifs_sb->tcon;
struct cifsFileInfo *cfile = (struct cifsFileInfo *) filp->private_data;
xid = GetXid();
rc = CIFSSMBQFileInfo(xid, tcon, cfile->netfid, &find_data);
if (rc == -EOPNOTSUPP || rc == -EINVAL) {
/*
* FIXME: legacy server -- fall back to path-based call?
* for now, just skip revalidating and mark inode for
* immediate reval.
*/
rc = 0;
CIFS_I(inode)->time = 0;
goto cgfi_exit;
} else if (rc == -EREMOTE) {
cifs_create_dfs_fattr(&fattr, inode->i_sb);
rc = 0;
} else if (rc)
goto cgfi_exit;
/*
* don't bother with SFU junk here -- just mark inode as needing
* revalidation.
*/
cifs_all_info_to_fattr(&fattr, &find_data, cifs_sb, false);
fattr.cf_uniqueid = CIFS_I(inode)->uniqueid;
fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
cifs_fattr_to_inode(inode, &fattr);
cgfi_exit:
FreeXid(xid);
return rc;
}
int cifs_get_inode_info(struct inode **pinode,
const unsigned char *full_path, FILE_ALL_INFO *pfindData,
struct super_block *sb, int xid, const __u16 *pfid)
@ -1389,135 +1492,103 @@ cifs_rename_exit:
return rc;
}
int cifs_revalidate(struct dentry *direntry)
static bool
cifs_inode_needs_reval(struct inode *inode)
{
struct cifsInodeInfo *cifs_i = CIFS_I(inode);
if (cifs_i->clientCanCacheRead)
return false;
if (!lookupCacheEnabled)
return true;
if (cifs_i->time == 0)
return true;
/* FIXME: the actimeo should be tunable */
if (time_after_eq(jiffies, cifs_i->time + HZ))
return true;
return false;
}
/* check invalid_mapping flag and zap the cache if it's set */
static void
cifs_invalidate_mapping(struct inode *inode)
{
int rc;
struct cifsInodeInfo *cifs_i = CIFS_I(inode);
cifs_i->invalid_mapping = false;
/* write back any cached data */
if (inode->i_mapping && inode->i_mapping->nrpages != 0) {
rc = filemap_write_and_wait(inode->i_mapping);
if (rc)
cifs_i->write_behind_rc = rc;
}
invalidate_remote_inode(inode);
}
int cifs_revalidate_file(struct file *filp)
{
int rc = 0;
struct inode *inode = filp->f_path.dentry->d_inode;
if (!cifs_inode_needs_reval(inode))
goto check_inval;
if (CIFS_SB(inode->i_sb)->tcon->unix_ext)
rc = cifs_get_file_info_unix(filp);
else
rc = cifs_get_file_info(filp);
check_inval:
if (CIFS_I(inode)->invalid_mapping)
cifs_invalidate_mapping(inode);
return rc;
}
/* revalidate a dentry's inode attributes */
int cifs_revalidate_dentry(struct dentry *dentry)
{
int xid;
int rc = 0, wbrc = 0;
char *full_path;
struct cifs_sb_info *cifs_sb;
struct cifsInodeInfo *cifsInode;
loff_t local_size;
struct timespec local_mtime;
bool invalidate_inode = false;
int rc = 0;
char *full_path = NULL;
struct inode *inode = dentry->d_inode;
struct super_block *sb = dentry->d_sb;
if (direntry->d_inode == NULL)
if (inode == NULL)
return -ENOENT;
cifsInode = CIFS_I(direntry->d_inode);
if (cifsInode == NULL)
return -ENOENT;
/* no sense revalidating inode info on file that no one can write */
if (CIFS_I(direntry->d_inode)->clientCanCacheRead)
return rc;
xid = GetXid();
cifs_sb = CIFS_SB(direntry->d_sb);
if (!cifs_inode_needs_reval(inode))
goto check_inval;
/* can not safely grab the rename sem here if rename calls revalidate
since that would deadlock */
full_path = build_path_from_dentry(direntry);
full_path = build_path_from_dentry(dentry);
if (full_path == NULL) {
rc = -ENOMEM;
FreeXid(xid);
return rc;
goto check_inval;
}
cFYI(1, ("Revalidate: %s inode 0x%p count %d dentry: 0x%p d_time %ld "
"jiffies %ld", full_path, direntry->d_inode,
direntry->d_inode->i_count.counter, direntry,
direntry->d_time, jiffies));
"jiffies %ld", full_path, inode, inode->i_count.counter,
dentry, dentry->d_time, jiffies));
if (cifsInode->time == 0) {
/* was set to zero previously to force revalidate */
} else if (time_before(jiffies, cifsInode->time + HZ) &&
lookupCacheEnabled) {
if ((S_ISREG(direntry->d_inode->i_mode) == 0) ||
(direntry->d_inode->i_nlink == 1)) {
kfree(full_path);
FreeXid(xid);
return rc;
} else {
cFYI(1, ("Have to revalidate file due to hardlinks"));
}
}
if (CIFS_SB(sb)->tcon->unix_ext)
rc = cifs_get_inode_info_unix(&inode, full_path, sb, xid);
else
rc = cifs_get_inode_info(&inode, full_path, NULL, sb,
xid, NULL);
/* save mtime and size */
local_mtime = direntry->d_inode->i_mtime;
local_size = direntry->d_inode->i_size;
if (cifs_sb->tcon->unix_ext) {
rc = cifs_get_inode_info_unix(&direntry->d_inode, full_path,
direntry->d_sb, xid);
if (rc) {
cFYI(1, ("error on getting revalidate info %d", rc));
/* if (rc != -ENOENT)
rc = 0; */ /* BB should we cache info on
certain errors? */
}
} else {
rc = cifs_get_inode_info(&direntry->d_inode, full_path, NULL,
direntry->d_sb, xid, NULL);
if (rc) {
cFYI(1, ("error on getting revalidate info %d", rc));
/* if (rc != -ENOENT)
rc = 0; */ /* BB should we cache info on
certain errors? */
}
}
/* should we remap certain errors, access denied?, to zero */
/* if not oplocked, we invalidate inode pages if mtime or file size
had changed on server */
if (timespec_equal(&local_mtime, &direntry->d_inode->i_mtime) &&
(local_size == direntry->d_inode->i_size)) {
cFYI(1, ("cifs_revalidate - inode unchanged"));
} else {
/* file may have changed on server */
if (cifsInode->clientCanCacheRead) {
/* no need to invalidate inode pages since we were the
only ones who could have modified the file and the
server copy is staler than ours */
} else {
invalidate_inode = true;
}
}
/* can not grab this sem since kernel filesys locking documentation
indicates i_mutex may be taken by the kernel on lookup and rename
which could deadlock if we grab the i_mutex here as well */
/* mutex_lock(&direntry->d_inode->i_mutex);*/
/* need to write out dirty pages here */
if (direntry->d_inode->i_mapping) {
/* do we need to lock inode until after invalidate completes
below? */
wbrc = filemap_fdatawrite(direntry->d_inode->i_mapping);
if (wbrc)
CIFS_I(direntry->d_inode)->write_behind_rc = wbrc;
}
if (invalidate_inode) {
/* shrink_dcache not necessary now that cifs dentry ops
are exported for negative dentries */
/* if (S_ISDIR(direntry->d_inode->i_mode))
shrink_dcache_parent(direntry); */
if (S_ISREG(direntry->d_inode->i_mode)) {
if (direntry->d_inode->i_mapping) {
wbrc = filemap_fdatawait(direntry->d_inode->i_mapping);
if (wbrc)
CIFS_I(direntry->d_inode)->write_behind_rc = wbrc;
}
/* may eventually have to do this for open files too */
if (list_empty(&(cifsInode->openFileList))) {
/* changed on server - flush read ahead pages */
cFYI(1, ("Invalidating read ahead data on "
"closed file"));
invalidate_remote_inode(direntry->d_inode);
}
}
}
/* mutex_unlock(&direntry->d_inode->i_mutex); */
check_inval:
if (CIFS_I(inode)->invalid_mapping)
cifs_invalidate_mapping(inode);
kfree(full_path);
FreeXid(xid);
@ -1527,7 +1598,7 @@ int cifs_revalidate(struct dentry *direntry)
int cifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat)
{
int err = cifs_revalidate(dentry);
int err = cifs_revalidate_dentry(dentry);
if (!err) {
generic_fillattr(dentry->d_inode, stat);
stat->blksize = CIFS_MAX_MSGSIZE;