swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 92ed301919932f777713b9172e525674157e983d authored by Linus Torvalds on 26 July 2020, 21:14:06 UTC
Linux 5.8-rc7
Linux 5.8-rc7
Tip revision: 92ed301
smb2file.c
/*
* fs/cifs/smb2file.c
*
* Copyright (C) International Business Machines Corp., 2002, 2011
* Author(s): Steve French (sfrench@us.ibm.com),
* Pavel Shilovsky ((pshilovsky@samba.org) 2012
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <asm/div64.h>
#include "cifsfs.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
#include "cifs_unicode.h"
#include "fscache.h"
#include "smb2proto.h"
int
smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms,
__u32 *oplock, FILE_ALL_INFO *buf)
{
int rc;
__le16 *smb2_path;
struct smb2_file_all_info *smb2_data = NULL;
__u8 smb2_oplock;
struct cifs_fid *fid = oparms->fid;
struct network_resiliency_req nr_ioctl_req;
smb2_path = cifs_convert_path_to_utf16(oparms->path, oparms->cifs_sb);
if (smb2_path == NULL) {
rc = -ENOMEM;
goto out;
}
smb2_data = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
GFP_KERNEL);
if (smb2_data == NULL) {
rc = -ENOMEM;
goto out;
}
oparms->desired_access |= FILE_READ_ATTRIBUTES;
smb2_oplock = SMB2_OPLOCK_LEVEL_BATCH;
rc = SMB2_open(xid, oparms, smb2_path, &smb2_oplock, smb2_data, NULL,
NULL, NULL);
if (rc)
goto out;
if (oparms->tcon->use_resilient) {
/* default timeout is 0, servers pick default (120 seconds) */
nr_ioctl_req.Timeout =
cpu_to_le32(oparms->tcon->handle_timeout);
nr_ioctl_req.Reserved = 0;
rc = SMB2_ioctl(xid, oparms->tcon, fid->persistent_fid,
fid->volatile_fid, FSCTL_LMR_REQUEST_RESILIENCY,
true /* is_fsctl */,
(char *)&nr_ioctl_req, sizeof(nr_ioctl_req),
CIFSMaxBufSize, NULL, NULL /* no return info */);
if (rc == -EOPNOTSUPP) {
cifs_dbg(VFS,
"resiliency not supported by server, disabling\n");
oparms->tcon->use_resilient = false;
} else if (rc)
cifs_dbg(FYI, "error %d setting resiliency\n", rc);
rc = 0;
}
if (buf) {
/* if open response does not have IndexNumber field - get it */
if (smb2_data->IndexNumber == 0) {
rc = SMB2_get_srv_num(xid, oparms->tcon,
fid->persistent_fid,
fid->volatile_fid,
&smb2_data->IndexNumber);
if (rc) {
/*
* let get_inode_info disable server inode
* numbers
*/
smb2_data->IndexNumber = 0;
rc = 0;
}
}
move_smb2_info_to_cifs(buf, smb2_data);
}
*oplock = smb2_oplock;
out:
kfree(smb2_data);
kfree(smb2_path);
return rc;
}
int
smb2_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
const unsigned int xid)
{
int rc = 0, stored_rc;
unsigned int max_num, num = 0, max_buf;
struct smb2_lock_element *buf, *cur;
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
struct cifsLockInfo *li, *tmp;
__u64 length = 1 + flock->fl_end - flock->fl_start;
struct list_head tmp_llist;
INIT_LIST_HEAD(&tmp_llist);
/*
* Accessing maxBuf is racy with cifs_reconnect - need to store value
* and check it before using.
*/
max_buf = tcon->ses->server->maxBuf;
if (max_buf < sizeof(struct smb2_lock_element))
return -EINVAL;
BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
max_num = max_buf / sizeof(struct smb2_lock_element);
buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
if (!buf)
return -ENOMEM;
cur = buf;
cifs_down_write(&cinode->lock_sem);
list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
if (flock->fl_start > li->offset ||
(flock->fl_start + length) <
(li->offset + li->length))
continue;
if (current->tgid != li->pid)
/*
* flock and OFD lock are associated with an open
* file description, not the process.
*/
if (!(flock->fl_flags & (FL_FLOCK | FL_OFDLCK)))
continue;
if (cinode->can_cache_brlcks) {
/*
* We can cache brlock requests - simply remove a lock
* from the file's list.
*/
list_del(&li->llist);
cifs_del_lock_waiters(li);
kfree(li);
continue;
}
cur->Length = cpu_to_le64(li->length);
cur->Offset = cpu_to_le64(li->offset);
cur->Flags = cpu_to_le32(SMB2_LOCKFLAG_UNLOCK);
/*
* We need to save a lock here to let us add it again to the
* file's list if the unlock range request fails on the server.
*/
list_move(&li->llist, &tmp_llist);
if (++num == max_num) {
stored_rc = smb2_lockv(xid, tcon,
cfile->fid.persistent_fid,
cfile->fid.volatile_fid,
current->tgid, num, buf);
if (stored_rc) {
/*
* We failed on the unlock range request - add
* all locks from the tmp list to the head of
* the file's list.
*/
cifs_move_llist(&tmp_llist,
&cfile->llist->locks);
rc = stored_rc;
} else
/*
* The unlock range request succeed - free the
* tmp list.
*/
cifs_free_llist(&tmp_llist);
cur = buf;
num = 0;
} else
cur++;
}
if (num) {
stored_rc = smb2_lockv(xid, tcon, cfile->fid.persistent_fid,
cfile->fid.volatile_fid, current->tgid,
num, buf);
if (stored_rc) {
cifs_move_llist(&tmp_llist, &cfile->llist->locks);
rc = stored_rc;
} else
cifs_free_llist(&tmp_llist);
}
up_write(&cinode->lock_sem);
kfree(buf);
return rc;
}
static int
smb2_push_mand_fdlocks(struct cifs_fid_locks *fdlocks, const unsigned int xid,
struct smb2_lock_element *buf, unsigned int max_num)
{
int rc = 0, stored_rc;
struct cifsFileInfo *cfile = fdlocks->cfile;
struct cifsLockInfo *li;
unsigned int num = 0;
struct smb2_lock_element *cur = buf;
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
list_for_each_entry(li, &fdlocks->locks, llist) {
cur->Length = cpu_to_le64(li->length);
cur->Offset = cpu_to_le64(li->offset);
cur->Flags = cpu_to_le32(li->type |
SMB2_LOCKFLAG_FAIL_IMMEDIATELY);
if (++num == max_num) {
stored_rc = smb2_lockv(xid, tcon,
cfile->fid.persistent_fid,
cfile->fid.volatile_fid,
current->tgid, num, buf);
if (stored_rc)
rc = stored_rc;
cur = buf;
num = 0;
} else
cur++;
}
if (num) {
stored_rc = smb2_lockv(xid, tcon,
cfile->fid.persistent_fid,
cfile->fid.volatile_fid,
current->tgid, num, buf);
if (stored_rc)
rc = stored_rc;
}
return rc;
}
int
smb2_push_mandatory_locks(struct cifsFileInfo *cfile)
{
int rc = 0, stored_rc;
unsigned int xid;
unsigned int max_num, max_buf;
struct smb2_lock_element *buf;
struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
struct cifs_fid_locks *fdlocks;
xid = get_xid();
/*
* Accessing maxBuf is racy with cifs_reconnect - need to store value
* and check it for zero before using.
*/
max_buf = tlink_tcon(cfile->tlink)->ses->server->maxBuf;
if (max_buf < sizeof(struct smb2_lock_element)) {
free_xid(xid);
return -EINVAL;
}
BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
max_num = max_buf / sizeof(struct smb2_lock_element);
buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
if (!buf) {
free_xid(xid);
return -ENOMEM;
}
list_for_each_entry(fdlocks, &cinode->llist, llist) {
stored_rc = smb2_push_mand_fdlocks(fdlocks, xid, buf, max_num);
if (stored_rc)
rc = stored_rc;
}
kfree(buf);
free_xid(xid);
return rc;
}