Merge commit 'tip/tracing/core' into oprofile/core
[safe/jmp/linux-2.6] / fs / cifs / file.c
index 50ca088..9b11a8f 100644 (file)
@@ -30,6 +30,8 @@
 #include <linux/writeback.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/delay.h>
+#include <linux/mount.h>
+#include <linux/slab.h>
 #include <asm/div64.h>
 #include "cifsfs.h"
 #include "cifspdu.h"
 #include "cifs_debug.h"
 #include "cifs_fs_sb.h"
 
-static inline struct cifsFileInfo *cifs_init_private(
-       struct cifsFileInfo *private_data, struct inode *inode,
-       struct file *file, __u16 netfid)
-{
-       memset(private_data, 0, sizeof(struct cifsFileInfo));
-       private_data->netfid = netfid;
-       private_data->pid = current->tgid;
-       mutex_init(&private_data->fh_mutex);
-       mutex_init(&private_data->lock_mutex);
-       INIT_LIST_HEAD(&private_data->llist);
-       private_data->pfile = file; /* needed for writepage */
-       private_data->pInode = inode;
-       private_data->invalidHandle = false;
-       private_data->closePend = false;
-       /* we have to track num writers to the inode, since writepages
-       does not tell us which handle the write is for so there can
-       be a close (overlapping with write) of the filehandle that
-       cifs_writepages chose to use */
-       atomic_set(&private_data->wrtPending, 0);
-
-       return private_data;
-}
-
 static inline int cifs_convert_flags(unsigned int flags)
 {
        if ((flags & O_ACCMODE) == O_RDONLY)
@@ -98,8 +77,10 @@ static inline fmode_t cifs_posix_convert_flags(unsigned int flags)
           reopening a file.  They had their effect on the original open */
        if (flags & O_APPEND)
                posix_flags |= (fmode_t)O_APPEND;
-       if (flags & O_SYNC)
-               posix_flags |= (fmode_t)O_SYNC;
+       if (flags & O_DSYNC)
+               posix_flags |= (fmode_t)O_DSYNC;
+       if (flags & __O_SYNC)
+               posix_flags |= (fmode_t)__O_SYNC;
        if (flags & O_DIRECTORY)
                posix_flags |= (fmode_t)O_DIRECTORY;
        if (flags & O_NOFOLLOW)
@@ -125,19 +106,14 @@ static inline int cifs_get_disposition(unsigned int flags)
 }
 
 /* all arguments to this function must be checked for validity in caller */
-static inline int cifs_posix_open_inode_helper(struct inode *inode,
-                       struct file *file, struct cifsInodeInfo *pCifsInode,
-                       struct cifsFileInfo *pCifsFile, int oplock, u16 netfid)
+static inline int
+cifs_posix_open_inode_helper(struct inode *inode, struct file *file,
+                            struct cifsInodeInfo *pCifsInode,
+                            struct cifsFileInfo *pCifsFile, __u32 oplock,
+                            u16 netfid)
 {
-       struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
-/*     struct timespec temp; */   /* BB REMOVEME BB */
 
-       file->private_data = kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
-       if (file->private_data == NULL)
-               return -ENOMEM;
-       pCifsFile = cifs_init_private(file->private_data, inode, file, netfid);
        write_lock(&GlobalSMBSeslock);
-       list_add(&pCifsFile->tlist, &cifs_sb->tcon->openFileList);
 
        pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
        if (pCifsInode == NULL) {
@@ -145,17 +121,6 @@ static inline int cifs_posix_open_inode_helper(struct inode *inode,
                return -EINVAL;
        }
 
-       /* want handles we can use to read with first
-          in the list so we do not have to walk the
-          list to search for one in write_begin */
-       if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
-               list_add_tail(&pCifsFile->flist,
-                             &pCifsInode->openFileList);
-       } else {
-               list_add(&pCifsFile->flist,
-                        &pCifsInode->openFileList);
-       }
-
        if (pCifsInode->clientCanCacheRead) {
                /* we have the inode open somewhere else
                   no need to discard cache data */
@@ -198,6 +163,38 @@ psx_client_can_cache:
        return 0;
 }
 
+static struct cifsFileInfo *
+cifs_fill_filedata(struct file *file)
+{
+       struct list_head *tmp;
+       struct cifsFileInfo *pCifsFile = NULL;
+       struct cifsInodeInfo *pCifsInode = NULL;
+
+       /* search inode for this file and fill in file->private_data */
+       pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
+       read_lock(&GlobalSMBSeslock);
+       list_for_each(tmp, &pCifsInode->openFileList) {
+               pCifsFile = list_entry(tmp, struct cifsFileInfo, flist);
+               if ((pCifsFile->pfile == NULL) &&
+                   (pCifsFile->pid == current->tgid)) {
+                       /* mode set in cifs_create */
+
+                       /* needed for writepage */
+                       pCifsFile->pfile = file;
+                       file->private_data = pCifsFile;
+                       break;
+               }
+       }
+       read_unlock(&GlobalSMBSeslock);
+
+       if (file->private_data != NULL) {
+               return pCifsFile;
+       } else if ((file->f_flags & O_CREAT) && (file->f_flags & O_EXCL))
+                       cERROR(1, ("could not find file instance for "
+                                  "new file %p", file));
+       return NULL;
+}
+
 /* all arguments to this function must be checked for validity in caller */
 static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
        struct cifsInodeInfo *pCifsInode, struct cifsFileInfo *pCifsFile,
@@ -207,17 +204,6 @@ static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
        struct timespec temp;
        int rc;
 
-       /* want handles we can use to read with first
-          in the list so we do not have to walk the
-          list to search for one in write_begin */
-       if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
-               list_add_tail(&pCifsFile->flist,
-                             &pCifsInode->openFileList);
-       } else {
-               list_add(&pCifsFile->flist,
-                        &pCifsInode->openFileList);
-       }
-       write_unlock(&GlobalSMBSeslock);
        if (pCifsInode->clientCanCacheRead) {
                /* we have the inode open somewhere else
                   no need to discard cache data */
@@ -227,15 +213,15 @@ static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
        /* BB need same check in cifs_create too? */
        /* if not oplocked, invalidate inode pages if mtime or file
           size changed */
-       temp = cifs_NTtimeToUnix(le64_to_cpu(buf->LastWriteTime));
+       temp = cifs_NTtimeToUnix(buf->LastWriteTime);
        if (timespec_equal(&file->f_path.dentry->d_inode->i_mtime, &temp) &&
                           (file->f_path.dentry->d_inode->i_size ==
                            (loff_t)le64_to_cpu(buf->EndOfFile))) {
                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;
@@ -267,12 +253,12 @@ client_can_cache:
 int cifs_open(struct inode *inode, struct file *file)
 {
        int rc = -EACCES;
-       int xid, oplock;
+       int xid;
+       __u32 oplock;
        struct cifs_sb_info *cifs_sb;
        struct cifsTconInfo *tcon;
        struct cifsFileInfo *pCifsFile;
        struct cifsInodeInfo *pCifsInode;
-       struct list_head *tmp;
        char *full_path = NULL;
        int desiredAccess;
        int disposition;
@@ -284,37 +270,19 @@ int cifs_open(struct inode *inode, struct file *file)
        cifs_sb = CIFS_SB(inode->i_sb);
        tcon = cifs_sb->tcon;
 
-       /* search inode for this file and fill in file->private_data */
        pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
-       read_lock(&GlobalSMBSeslock);
-       list_for_each(tmp, &pCifsInode->openFileList) {
-               pCifsFile = list_entry(tmp, struct cifsFileInfo,
-                                      flist);
-               if ((pCifsFile->pfile == NULL) &&
-                   (pCifsFile->pid == current->tgid)) {
-                       /* mode set in cifs_create */
-
-                       /* needed for writepage */
-                       pCifsFile->pfile = file;
-
-                       file->private_data = pCifsFile;
-                       break;
-               }
-       }
-       read_unlock(&GlobalSMBSeslock);
-
-       if (file->private_data != NULL) {
+       pCifsFile = cifs_fill_filedata(file);
+       if (pCifsFile) {
                rc = 0;
                FreeXid(xid);
                return rc;
-       } else if ((file->f_flags & O_CREAT) && (file->f_flags & O_EXCL))
-                       cERROR(1, ("could not find file instance for "
-                                  "new file %p", file));
+       }
 
        full_path = build_path_from_dentry(file->f_path.dentry);
        if (full_path == NULL) {
+               rc = -ENOMEM;
                FreeXid(xid);
-               return -ENOMEM;
+               return rc;
        }
 
        cFYI(1, ("inode = 0x%p file flags are 0x%x for %s",
@@ -331,7 +299,7 @@ int cifs_open(struct inode *inode, struct file *file)
                        le64_to_cpu(tcon->fsUnixInfo.Capability))) {
                int oflags = (int) cifs_posix_convert_flags(file->f_flags);
                /* can not refresh inode info since size could be stale */
-               rc = cifs_posix_open(full_path, &inode, inode->i_sb,
+               rc = cifs_posix_open(full_path, &inode, file->f_path.mnt,
                                     cifs_sb->mnt_file_mode /* ignored */,
                                     oflags, &oplock, &netfid, xid);
                if (rc == 0) {
@@ -339,6 +307,7 @@ int cifs_open(struct inode *inode, struct file *file)
                        /* no need for special case handling of setting mode
                           on read only files needed here */
 
+                       pCifsFile = cifs_fill_filedata(file);
                        cifs_posix_open_inode_helper(inode, file, pCifsInode,
                                                     pCifsFile, oplock, netfid);
                        goto out;
@@ -420,24 +389,17 @@ int cifs_open(struct inode *inode, struct file *file)
                cFYI(1, ("cifs_open returned 0x%x", rc));
                goto out;
        }
-       file->private_data =
-               kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
+
+       pCifsFile = cifs_new_fileinfo(inode, netfid, file, file->f_path.mnt,
+                                       file->f_flags);
+       file->private_data = pCifsFile;
        if (file->private_data == NULL) {
                rc = -ENOMEM;
                goto out;
        }
-       pCifsFile = cifs_init_private(file->private_data, inode, file, netfid);
-       write_lock(&GlobalSMBSeslock);
-       list_add(&pCifsFile->tlist, &tcon->openFileList);
 
-       pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
-       if (pCifsInode) {
-               rc = cifs_open_inode_helper(inode, file, pCifsInode,
-                                           pCifsFile, tcon,
-                                           &oplock, buf, full_path, xid);
-       } else {
-               write_unlock(&GlobalSMBSeslock);
-       }
+       rc = cifs_open_inode_helper(inode, file, pCifsInode, pCifsFile, tcon,
+                                   &oplock, buf, full_path, xid);
 
        if (oplock & CIFS_CREATE_ACTION) {
                /* time to set mode which we can not set earlier due to
@@ -452,9 +414,9 @@ int cifs_open(struct inode *inode, struct file *file)
                                .mtime  = NO_CHANGE_64,
                                .device = 0,
                        };
-                       CIFSSMBUnixSetInfo(xid, tcon, full_path, &args,
-                                           cifs_sb->local_nls,
-                                           cifs_sb->mnt_cifs_flags &
+                       CIFSSMBUnixSetPathInfo(xid, tcon, full_path, &args,
+                                              cifs_sb->local_nls,
+                                              cifs_sb->mnt_cifs_flags &
                                                CIFS_MOUNT_MAP_SPECIAL_CHR);
                }
        }
@@ -480,7 +442,8 @@ static int cifs_relock_file(struct cifsFileInfo *cifsFile)
 static int cifs_reopen_file(struct file *file, bool can_flush)
 {
        int rc = -EACCES;
-       int xid, oplock;
+       int xid;
+       __u32 oplock;
        struct cifs_sb_info *cifs_sb;
        struct cifsTconInfo *tcon;
        struct cifsFileInfo *pCifsFile;
@@ -497,11 +460,12 @@ static int cifs_reopen_file(struct file *file, bool can_flush)
                return -EBADF;
 
        xid = GetXid();
-       mutex_unlock(&pCifsFile->fh_mutex);
+       mutex_lock(&pCifsFile->fh_mutex);
        if (!pCifsFile->invalidHandle) {
-               mutex_lock(&pCifsFile->fh_mutex);
+               mutex_unlock(&pCifsFile->fh_mutex);
+               rc = 0;
                FreeXid(xid);
-               return 0;
+               return rc;
        }
 
        if (file->f_path.dentry == NULL) {
@@ -530,7 +494,7 @@ static int cifs_reopen_file(struct file *file, bool can_flush)
        if (full_path == NULL) {
                rc = -ENOMEM;
 reopen_error_exit:
-               mutex_lock(&pCifsFile->fh_mutex);
+               mutex_unlock(&pCifsFile->fh_mutex);
                FreeXid(xid);
                return rc;
        }
@@ -548,7 +512,7 @@ reopen_error_exit:
                        le64_to_cpu(tcon->fsUnixInfo.Capability))) {
                int oflags = (int) cifs_posix_convert_flags(file->f_flags);
                /* can not refresh inode info since size could be stale */
-               rc = cifs_posix_open(full_path, NULL, inode->i_sb,
+               rc = cifs_posix_open(full_path, NULL, file->f_path.mnt,
                                     cifs_sb->mnt_file_mode /* ignored */,
                                     oflags, &oplock, &netfid, xid);
                if (rc == 0) {
@@ -572,14 +536,14 @@ reopen_error_exit:
                         cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
                                CIFS_MOUNT_MAP_SPECIAL_CHR);
        if (rc) {
-               mutex_lock(&pCifsFile->fh_mutex);
+               mutex_unlock(&pCifsFile->fh_mutex);
                cFYI(1, ("cifs_open returned 0x%x", rc));
                cFYI(1, ("oplock: %d", oplock));
        } else {
 reopen_success:
                pCifsFile->netfid = netfid;
                pCifsFile->invalidHandle = false;
-               mutex_lock(&pCifsFile->fh_mutex);
+               mutex_unlock(&pCifsFile->fh_mutex);
                pCifsInode = CIFS_I(inode);
                if (pCifsInode) {
                        if (can_flush) {
@@ -646,7 +610,7 @@ int cifs_close(struct inode *inode, struct file *file)
                        if (!pTcon->need_reconnect) {
                                write_unlock(&GlobalSMBSeslock);
                                timeout = 2;
-                               while ((atomic_read(&pSMBFile->wrtPending) != 0)
+                               while ((atomic_read(&pSMBFile->count) != 1)
                                        && (timeout <= 2048)) {
                                        /* Give write a better chance to get to
                                        server ahead of the close.  We do not
@@ -660,8 +624,6 @@ int cifs_close(struct inode *inode, struct file *file)
                                        msleep(timeout);
                                        timeout *= 4;
                                }
-                               if (atomic_read(&pSMBFile->wrtPending))
-                                       cERROR(1, ("close with pending write"));
                                if (!pTcon->need_reconnect &&
                                    !pSMBFile->invalidHandle)
                                        rc = CIFSSMBClose(xid, pTcon,
@@ -684,24 +646,7 @@ int cifs_close(struct inode *inode, struct file *file)
                list_del(&pSMBFile->flist);
                list_del(&pSMBFile->tlist);
                write_unlock(&GlobalSMBSeslock);
-               timeout = 10;
-               /* We waited above to give the SMBWrite a chance to issue
-                  on the wire (so we do not get SMBWrite returning EBADF
-                  if writepages is racing with close.  Note that writepages
-                  does not specify a file handle, so it is possible for a file
-                  to be opened twice, and the application close the "wrong"
-                  file handle - in these cases we delay long enough to allow
-                  the SMBWrite to get on the wire before the SMB Close.
-                  We allow total wait here over 45 seconds, more than
-                  oplock break time, and more than enough to allow any write
-                  to complete on the server, or to time out on the client */
-               while ((atomic_read(&pSMBFile->wrtPending) != 0)
-                               && (timeout <= 50000)) {
-                       cERROR(1, ("writes pending, delay free of handle"));
-                       msleep(timeout);
-                       timeout *= 8;
-               }
-               kfree(file->private_data);
+               cifsFileInfo_put(file->private_data);
                file->private_data = NULL;
        } else
                rc = -EBADF;
@@ -851,8 +796,9 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
        tcon = cifs_sb->tcon;
 
        if (file->private_data == NULL) {
+               rc = -EBADF;
                FreeXid(xid);
-               return -EBADF;
+               return rc;
        }
        netfid = ((struct cifsFileInfo *)file->private_data)->netfid;
 
@@ -893,8 +839,32 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
 
                } else {
                        /* if rc == ERR_SHARING_VIOLATION ? */
-                       rc = 0; /* do not change lock type to unlock
-                                  since range in use */
+                       rc = 0;
+
+                       if (lockType & LOCKING_ANDX_SHARED_LOCK) {
+                               pfLock->fl_type = F_WRLCK;
+                       } else {
+                               rc = CIFSSMBLock(xid, tcon, netfid, length,
+                                       pfLock->fl_start, 0, 1,
+                                       lockType | LOCKING_ANDX_SHARED_LOCK,
+                                       0 /* wait flag */);
+                               if (rc == 0) {
+                                       rc = CIFSSMBLock(xid, tcon, netfid,
+                                               length, pfLock->fl_start, 1, 0,
+                                               lockType |
+                                               LOCKING_ANDX_SHARED_LOCK,
+                                               0 /* wait flag */);
+                                       pfLock->fl_type = F_RDLCK;
+                                       if (rc != 0)
+                                               cERROR(1, ("Error unlocking "
+                                               "previously locked range %d "
+                                               "during test of lock", rc));
+                                       rc = 0;
+                               } else {
+                                       pfLock->fl_type = F_WRLCK;
+                                       rc = 0;
+                               }
+                       }
                }
 
                FreeXid(xid);
@@ -1238,7 +1208,7 @@ struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode)
                        if (!open_file->invalidHandle) {
                                /* found a good file */
                                /* lock it so it will not be closed on us */
-                               atomic_inc(&open_file->wrtPending);
+                               cifsFileInfo_get(open_file);
                                read_unlock(&GlobalSMBSeslock);
                                return open_file;
                        } /* else might as well continue, and look for
@@ -1278,7 +1248,7 @@ refind_writable:
                if (open_file->pfile &&
                    ((open_file->pfile->f_flags & O_RDWR) ||
                     (open_file->pfile->f_flags & O_WRONLY))) {
-                       atomic_inc(&open_file->wrtPending);
+                       cifsFileInfo_get(open_file);
 
                        if (!open_file->invalidHandle) {
                                /* found a good writable file */
@@ -1295,7 +1265,7 @@ refind_writable:
                                else { /* start over in case this was deleted */
                                       /* since the list could be modified */
                                        read_lock(&GlobalSMBSeslock);
-                                       atomic_dec(&open_file->wrtPending);
+                                       cifsFileInfo_put(open_file);
                                        goto refind_writable;
                                }
                        }
@@ -1311,7 +1281,7 @@ refind_writable:
                        read_lock(&GlobalSMBSeslock);
                        /* can not use this handle, no write
                           pending on this one after all */
-                       atomic_dec(&open_file->wrtPending);
+                       cifsFileInfo_put(open_file);
 
                        if (open_file->closePend) /* list could have changed */
                                goto refind_writable;
@@ -1375,7 +1345,7 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
        if (open_file) {
                bytes_written = cifs_write(open_file->pfile, write_data,
                                           to-from, &offset);
-               atomic_dec(&open_file->wrtPending);
+               cifsFileInfo_put(open_file);
                /* Does mm or vfs already set times? */
                inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
                if ((bytes_written > 0) && (offset))
@@ -1564,7 +1534,7 @@ retry:
                                                   bytes_to_write, offset,
                                                   &bytes_written, iov, n_iov,
                                                   long_op);
-                               atomic_dec(&open_file->wrtPending);
+                               cifsFileInfo_put(open_file);
                                cifs_update_eof(cifsi, offset, bytes_written);
 
                                if (rc || bytes_written < bytes_to_write) {
@@ -1811,8 +1781,9 @@ ssize_t cifs_user_read(struct file *file, char __user *read_data,
        pTcon = cifs_sb->tcon;
 
        if (file->private_data == NULL) {
+               rc = -EBADF;
                FreeXid(xid);
-               return -EBADF;
+               return rc;
        }
        open_file = (struct cifsFileInfo *)file->private_data;
 
@@ -1891,8 +1862,9 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
        pTcon = cifs_sb->tcon;
 
        if (file->private_data == NULL) {
+               rc = -EBADF;
                FreeXid(xid);
-               return -EBADF;
+               return rc;
        }
        open_file = (struct cifsFileInfo *)file->private_data;
 
@@ -1943,11 +1915,10 @@ 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);
@@ -2025,8 +1996,9 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 
        xid = GetXid();
        if (file->private_data == NULL) {
+               rc = -EBADF;
                FreeXid(xid);
-               return -EBADF;
+               return rc;
        }
        open_file = (struct cifsFileInfo *)file->private_data;
        cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
@@ -2191,8 +2163,9 @@ static int cifs_readpage(struct file *file, struct page *page)
        xid = GetXid();
 
        if (file->private_data == NULL) {
+               rc = -EBADF;
                FreeXid(xid);
-               return -EBADF;
+               return rc;
        }
 
        cFYI(1, ("readpage %p at offset %d 0x%x\n",
@@ -2327,6 +2300,73 @@ out:
        return rc;
 }
 
+static void
+cifs_oplock_break(struct slow_work *work)
+{
+       struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
+                                                 oplock_break);
+       struct inode *inode = cfile->pInode;
+       struct cifsInodeInfo *cinode = CIFS_I(inode);
+       struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->mnt->mnt_sb);
+       int rc, waitrc = 0;
+
+       if (inode && S_ISREG(inode->i_mode)) {
+#ifdef CONFIG_CIFS_EXPERIMENTAL
+               if (cinode->clientCanCacheAll == 0)
+                       break_lease(inode, O_RDONLY);
+               else if (cinode->clientCanCacheRead == 0)
+                       break_lease(inode, O_WRONLY);
+#endif
+               rc = filemap_fdatawrite(inode->i_mapping);
+               if (cinode->clientCanCacheRead == 0) {
+                       waitrc = filemap_fdatawait(inode->i_mapping);
+                       invalidate_remote_inode(inode);
+               }
+               if (!rc)
+                       rc = waitrc;
+               if (rc)
+                       cinode->write_behind_rc = rc;
+               cFYI(1, ("Oplock flush inode %p rc %d", inode, rc));
+       }
+
+       /*
+        * releasing stale oplock after recent reconnect of smb session using
+        * a now incorrect file handle is not a data integrity issue but do
+        * not bother sending an oplock release if session to server still is
+        * disconnected since oplock already released by the server
+        */
+       if (!cfile->closePend && !cfile->oplock_break_cancelled) {
+               rc = CIFSSMBLock(0, cifs_sb->tcon, cfile->netfid, 0, 0, 0, 0,
+                                LOCKING_ANDX_OPLOCK_RELEASE, false);
+               cFYI(1, ("Oplock release rc = %d", rc));
+       }
+}
+
+static int
+cifs_oplock_break_get(struct slow_work *work)
+{
+       struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
+                                                 oplock_break);
+       mntget(cfile->mnt);
+       cifsFileInfo_get(cfile);
+       return 0;
+}
+
+static void
+cifs_oplock_break_put(struct slow_work *work)
+{
+       struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
+                                                 oplock_break);
+       mntput(cfile->mnt);
+       cifsFileInfo_put(cfile);
+}
+
+const struct slow_work_ops cifs_oplock_break_ops = {
+       .get_ref        = cifs_oplock_break_get,
+       .put_ref        = cifs_oplock_break_put,
+       .execute        = cifs_oplock_break,
+};
+
 const struct address_space_operations cifs_addr_ops = {
        .readpage = cifs_readpage,
        .readpages = cifs_readpages,