CIFS: Use pid saved from cifsFileInfo in writepages and set_file_size

We need it to make them work with mandatory locking style because
we can fail in a situation like when kernel need to flush dirty pages
and there is a lock held by a process who opened file.

Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 21 insertions, 10 deletions

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 00b926ce7935..dfc0d35b1470 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -857,7 +857,7 @@ cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
                 cifsi->server_eof = end_of_write;
 }
 
-static ssize_t cifs_write(struct cifsFileInfo *open_file,
+static ssize_t cifs_write(struct cifsFileInfo *open_file, __u32 pid,
                           const char *write_data, size_t write_size,
                           loff_t *poffset)
 {
@@ -869,6 +869,7 @@ static ssize_t cifs_write(struct cifsFileInfo *open_file,
         int xid;
         struct dentry *dentry = open_file->dentry;
         struct cifsInodeInfo *cifsi = CIFS_I(dentry->d_inode);
+        struct cifs_io_parms io_parms;
 
         cifs_sb = CIFS_SB(dentry->d_sb);
 
@@ -901,8 +902,13 @@ static ssize_t cifs_write(struct cifsFileInfo *open_file,
                         /* iov[0] is reserved for smb header */
                         iov[1].iov_base = (char *)write_data + total_written;
                         iov[1].iov_len = len;
-                        rc = CIFSSMBWrite2(xid, pTcon, open_file->netfid, len,
-                                           *poffset, &bytes_written, iov, 1, 0);
+                        io_parms.netfid = open_file->netfid;
+                        io_parms.pid = pid;
+                        io_parms.tcon = pTcon;
+                        io_parms.offset = *poffset;
+                        io_parms.length = len;
+                        rc = CIFSSMBWrite2(xid, &io_parms, &bytes_written, iov,
+                                           1, 0);
                 }
                 if (rc || (bytes_written == 0)) {
                         if (total_written)
@@ -1071,8 +1077,8 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
 
         open_file = find_writable_file(CIFS_I(mapping->host), false);
         if (open_file) {
-                bytes_written = cifs_write(open_file, write_data,
-                                           to - from, &offset);
+                bytes_written = cifs_write(open_file, open_file->pid,
+                                           write_data, to - from, &offset);
                 cifsFileInfo_put(open_file);
                 /* Does mm or vfs already set times? */
                 inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
@@ -1363,8 +1369,8 @@ static int cifs_write_end(struct file *file, struct address_space *mapping,
                 /* BB check if anything else missing out of ppw
                    such as updating last write time */
                 page_data = kmap(page);
-                rc = cifs_write(file->private_data, page_data + offset,
-                                copied, &pos);
+                rc = cifs_write(file->private_data, current->tgid,
+                                page_data + offset, copied, &pos);
                 /* if (rc < 0) should we set writebehind rc? */
                 kunmap(page);
 
@@ -1515,6 +1521,7 @@ cifs_iovec_write(struct file *file, const struct iovec *iov,
         struct cifsFileInfo *open_file;
         struct cifsTconInfo *pTcon;
         struct cifs_sb_info *cifs_sb;
+        struct cifs_io_parms io_parms;
         int xid, rc;
 
         len = iov_length(iov, nr_segs);
@@ -1573,9 +1580,13 @@ cifs_iovec_write(struct file *file, const struct iovec *iov,
                                 if (rc != 0)
                                         break;
                         }
-                        rc = CIFSSMBWrite2(xid, pTcon, open_file->netfid,
-                                           cur_len, *poffset, &written,
-                                           to_send, npages, 0);
+                        io_parms.netfid = open_file->netfid;
+                        io_parms.pid = current->tgid;
+                        io_parms.tcon = pTcon;
+                        io_parms.offset = *poffset;
+                        io_parms.length = cur_len;
+                        rc = CIFSSMBWrite2(xid, &io_parms, &written, to_send,
+                                           npages, 0);
                 } while (rc == -EAGAIN);
 
                 for (i = 0; i < npages; i++)