CIFS: Reconnect durable handles for SMB2

On reconnects, we need to reopen file and then obtain all byte-range
locks held by the client. SMB2 protocol provides feature to make
this process atomic by reconnecting to the same file handle
with all it's byte-range locks. This patch adds this capability
for SMB2 shares.

Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steven French <steven@steven-GA-970A-DS3.(none)>
This commit is contained in:
Pavel Shilovsky 2013-07-09 18:40:58 +04:00 committed by Steve French
parent 064f6047a1
commit 9cbc0b7339
8 changed files with 58 additions and 12 deletions

View file

@ -920,6 +920,7 @@ struct cifs_open_parms {
int create_options;
const char *path;
struct cifs_fid *fid;
bool reconnect:1;
};
struct cifs_fid {

View file

@ -327,6 +327,7 @@ cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
oparms.disposition = disposition;
oparms.path = full_path;
oparms.fid = fid;
oparms.reconnect = false;
rc = server->ops->open(xid, &oparms, oplock, buf);
if (rc) {

View file

@ -232,6 +232,7 @@ cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
oparms.disposition = disposition;
oparms.path = full_path;
oparms.fid = fid;
oparms.reconnect = false;
rc = server->ops->open(xid, &oparms, oplock, buf);
@ -594,7 +595,6 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
int desired_access;
int disposition = FILE_OPEN;
int create_options = CREATE_NOT_DIR;
struct cifs_fid fid;
struct cifs_open_parms oparms;
xid = get_xid();
@ -645,7 +645,7 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
rc = cifs_posix_open(full_path, NULL, inode->i_sb,
cifs_sb->mnt_file_mode /* ignored */,
oflags, &oplock, &fid.netfid, xid);
oflags, &oplock, &cfile->fid.netfid, xid);
if (rc == 0) {
cifs_dbg(FYI, "posix reopen succeeded\n");
goto reopen_success;
@ -662,7 +662,7 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
create_options |= CREATE_OPEN_BACKUP_INTENT;
if (server->ops->get_lease_key)
server->ops->get_lease_key(inode, &fid);
server->ops->get_lease_key(inode, &cfile->fid);
oparms.tcon = tcon;
oparms.cifs_sb = cifs_sb;
@ -670,7 +670,8 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
oparms.create_options = create_options;
oparms.disposition = disposition;
oparms.path = full_path;
oparms.fid = &fid;
oparms.fid = &cfile->fid;
oparms.reconnect = true;
/*
* Can not refresh inode by passing in file_info buf to be returned by
@ -710,8 +711,9 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
* to the server to get the new inode info.
*/
server->ops->set_fid(cfile, &fid, oplock);
cifs_relock_file(cfile);
server->ops->set_fid(cfile, &cfile->fid, oplock);
if (oparms.reconnect)
cifs_relock_file(cfile);
reopen_error_exit:
kfree(full_path);
@ -1508,6 +1510,7 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
if (!rc)
goto out;
/*
* Windows 7 server can delay breaking lease from read to None
* if we set a byte-range lock on a file - break it explicitly

View file

@ -40,7 +40,8 @@ smb2_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
oplock &= 0xFF;
if (oplock == SMB2_OPLOCK_LEVEL_NOCHANGE)
return;
if (oplock == SMB2_OPLOCK_LEVEL_EXCLUSIVE) {
if (oplock == SMB2_OPLOCK_LEVEL_EXCLUSIVE ||
oplock == SMB2_OPLOCK_LEVEL_BATCH) {
cinode->clientCanCacheAll = true;
cinode->clientCanCacheRead = true;
cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n",

View file

@ -58,6 +58,7 @@ smb2_open_op_close(const unsigned int xid, struct cifs_tcon *tcon,
oparms.disposition = create_disposition;
oparms.create_options = create_options;
oparms.fid = &fid;
oparms.reconnect = false;
rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL);
if (rc) {

View file

@ -227,6 +227,7 @@ smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
oparms.disposition = FILE_OPEN;
oparms.create_options = 0;
oparms.fid = &fid;
oparms.reconnect = false;
rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL);
if (rc) {
@ -460,6 +461,7 @@ smb2_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
oparms.disposition = FILE_OPEN;
oparms.create_options = 0;
oparms.fid = fid;
oparms.reconnect = false;
rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL);
kfree(utf16_path);
@ -546,6 +548,7 @@ smb2_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
oparms.disposition = FILE_OPEN;
oparms.create_options = 0;
oparms.fid = &fid;
oparms.reconnect = false;
rc = SMB2_open(xid, &oparms, &srch_path, &oplock, NULL);
if (rc)

View file

@ -857,7 +857,7 @@ create_durable_buf(void)
return NULL;
buf->ccontext.DataOffset = cpu_to_le16(offsetof
(struct create_durable, Reserved));
(struct create_durable, Data));
buf->ccontext.DataLength = cpu_to_le32(16);
buf->ccontext.NameOffset = cpu_to_le16(offsetof
(struct create_durable, Name));
@ -869,6 +869,30 @@ create_durable_buf(void)
return buf;
}
static struct create_durable *
create_reconnect_durable_buf(struct cifs_fid *fid)
{
struct create_durable *buf;
buf = kzalloc(sizeof(struct create_durable), GFP_KERNEL);
if (!buf)
return NULL;
buf->ccontext.DataOffset = cpu_to_le16(offsetof
(struct create_durable, Data));
buf->ccontext.DataLength = cpu_to_le32(16);
buf->ccontext.NameOffset = cpu_to_le16(offsetof
(struct create_durable, Name));
buf->ccontext.NameLength = cpu_to_le16(4);
buf->Data.Fid.PersistentFileId = fid->persistent_fid;
buf->Data.Fid.VolatileFileId = fid->volatile_fid;
buf->Name[0] = 'D';
buf->Name[1] = 'H';
buf->Name[2] = 'n';
buf->Name[3] = 'C';
return buf;
}
static __u8
parse_lease_state(struct smb2_create_rsp *rsp)
{
@ -924,12 +948,18 @@ add_lease_context(struct kvec *iov, unsigned int *num_iovec, __u8 *oplock)
}
static int
add_durable_context(struct kvec *iov, unsigned int *num_iovec)
add_durable_context(struct kvec *iov, unsigned int *num_iovec,
struct cifs_open_parms *oparms)
{
struct smb2_create_req *req = iov[0].iov_base;
unsigned int num = *num_iovec;
iov[num].iov_base = create_durable_buf();
if (oparms->reconnect) {
iov[num].iov_base = create_reconnect_durable_buf(oparms->fid);
/* indicate that we don't need to relock the file */
oparms->reconnect = false;
} else
iov[num].iov_base = create_durable_buf();
if (iov[num].iov_base == NULL)
return -ENOMEM;
iov[num].iov_len = sizeof(struct create_durable);
@ -1037,7 +1067,7 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
(struct create_context *)iov[num_iovecs-1].iov_base;
ccontext->Next = sizeof(struct create_lease);
}
rc = add_durable_context(iov, &num_iovecs);
rc = add_durable_context(iov, &num_iovecs, oparms);
if (rc) {
cifs_small_buf_release(req);
kfree(copy_path);

View file

@ -488,7 +488,13 @@ struct create_lease {
struct create_durable {
struct create_context ccontext;
__u8 Name[8];
__u8 Reserved[16];
union {
__u8 Reserved[16];
struct {
__u64 PersistentFileId;
__u64 VolatileFileId;
} Fid;
} Data;
} __packed;
/* this goes in the ioctl buffer when doing a copychunk request */