CIFS: Create routine find_writable_file to reduce redundant code

Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

3 files changed, 50 insertions, 119 deletions

diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index fb3e76043c50..d301149b1bb0 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -54,6 +54,7 @@ extern int checkSMBhdr(struct smb_hdr *smb, __u16 mid);
 extern int checkSMB(struct smb_hdr *smb, __u16 mid, int length);
 extern int is_valid_oplock_break(struct smb_hdr *smb);
 extern int is_size_safe_to_change(struct cifsInodeInfo *);
+extern struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *);
 extern unsigned int smbCalcSize(struct smb_hdr *ptr);
 extern unsigned int smbCalcSize_LE(struct smb_hdr *ptr);
 extern int decode_negTokenInit(unsigned char *security_blob, int length,
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 941108352547..94875455d7fa 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -904,6 +904,25 @@ static ssize_t cifs_write(struct file *file, const char *write_data,
         return total_written;
 }
 
+static struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
+{
+        struct cifsFileInfo *open_file;
+
+        read_lock(&GlobalSMBSeslock);
+        list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
+                if (open_file->closePend)
+                        continue;
+                if (open_file->pfile &&
+                    ((open_file->pfile->f_flags & O_RDWR) ||
+                     (open_file->pfile->f_flags & O_WRONLY))) {
+                        read_unlock(&GlobalSMBSeslock);
+                        return open_file;
+                }
+        }
+        read_unlock(&GlobalSMBSeslock);
+        return NULL;
+}
+
 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
 {
         struct address_space *mapping = page->mapping;
@@ -914,10 +933,7 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
         struct cifs_sb_info *cifs_sb;
         struct cifsTconInfo *pTcon;
         struct inode *inode;
-        struct cifsInodeInfo *cifsInode;
-        struct cifsFileInfo *open_file = NULL;
-        struct list_head *tmp;
-        struct list_head *tmp1;
+        struct cifsFileInfo *open_file;
 
         if (!mapping || !mapping->host)
                 return -EFAULT;
@@ -945,49 +961,19 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
         if (mapping->host->i_size - offset < (loff_t)to)
                 to = (unsigned)(mapping->host->i_size - offset); 
 
-        cifsInode = CIFS_I(mapping->host);
-        read_lock(&GlobalSMBSeslock); 
-        /* BB we should start at the end */
-        list_for_each_safe(tmp, tmp1, &cifsInode->openFileList) {            
-                open_file = list_entry(tmp, struct cifsFileInfo, flist);
-                if (open_file->closePend)
-                        continue;
-                /* We check if file is open for writing first */
-                if ((open_file->pfile) && 
-                   ((open_file->pfile->f_flags & O_RDWR) || 
-                        (open_file->pfile->f_flags & O_WRONLY))) {
-                        read_unlock(&GlobalSMBSeslock);
-                        bytes_written = cifs_write(open_file->pfile,
-                                                write_data, to-from,
-                                                &offset);
-                        read_lock(&GlobalSMBSeslock);
+        open_file = find_writable_file(CIFS_I(mapping->host));
+        if (open_file) {
+                bytes_written = cifs_write(open_file->pfile, write_data,
+                                           to-from, &offset);
                 /* Does mm or vfs already set times? */
-                        inode->i_atime = 
-                        inode->i_mtime = current_fs_time(inode->i_sb);
-                        if ((bytes_written > 0) && (offset)) {
-                                rc = 0;
-                        } else if (bytes_written < 0) {
-                                if (rc == -EBADF) {
-                                /* have seen a case in which kernel seemed to
-                                   have closed/freed a file even with writes
-                                   active so we might as well see if there are
-                                   other file structs to try for the same
-                                   inode before giving up */
-                                        continue;
-                                } else
-                                        rc = bytes_written;
-                        }
-                        break;  /* now that we found a valid file handle and
-                                   tried to write to it we are done, no sense
-                                   continuing to loop looking for another */
-                }
-                if (tmp->next == NULL) {
-                        cFYI(1, ("File instance %p removed", tmp));
-                        break;
+                inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
+                if ((bytes_written > 0) && (offset)) {
+                        rc = 0;
+                } else if (bytes_written < 0) {
+                        if (rc != -EBADF)
+                                rc = bytes_written;
                 }
-        }
-        read_unlock(&GlobalSMBSeslock);
-        if (open_file == NULL) {
+        } else {
                 cFYI(1, ("No writeable filehandles for inode"));
                 rc = -EIO;
         }
@@ -1604,40 +1590,12 @@ static int cifs_readpage(struct file *file, struct page *page)
    page caching in the current Linux kernel design */
 int is_size_safe_to_change(struct cifsInodeInfo *cifsInode)
 {
-        struct list_head *tmp;
-        struct list_head *tmp1;
-        struct cifsFileInfo *open_file = NULL;
-        int rc = TRUE;
-
-        if (cifsInode == NULL)
-                return rc;
-
-        read_lock(&GlobalSMBSeslock); 
-        list_for_each_safe(tmp, tmp1, &cifsInode->openFileList) {            
-                open_file = list_entry(tmp, struct cifsFileInfo, flist);
-                if (open_file == NULL)
-                        break;
-                if (open_file->closePend)
-                        continue;
-        /* We check if file is open for writing,   
-           BB we could supplement this with a check to see if file size
-           changes have been flushed to server - ie inode metadata dirty */
-                if ((open_file->pfile) && 
-                    ((open_file->pfile->f_flags & O_RDWR) || 
-                    (open_file->pfile->f_flags & O_WRONLY))) {
-                        rc = FALSE;
-                        break;
-                }
-                if (tmp->next == NULL) {
-                        cFYI(1, ("File instance %p removed", tmp));
-                        break;
-                }
-        }
-        read_unlock(&GlobalSMBSeslock);
-        return rc;
+        if (cifsInode && find_writable_file(cifsInode))
+                return 0;
+        else
+                return 1;
 }
 
-
 static int cifs_prepare_write(struct file *file, struct page *page,
         unsigned from, unsigned to)
 {
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index ca3af4eafcb2..49efdefcff7c 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -995,7 +995,6 @@ int cifs_setattr(struct dentry *direntry, struct iattr *attrs)
         filemap_fdatawait(direntry->d_inode->i_mapping);
 
         if (attrs->ia_valid & ATTR_SIZE) {
-                read_lock(&GlobalSMBSeslock);
                 /* To avoid spurious oplock breaks from server, in the case of
                    inodes that we already have open, avoid doing path based
                    setting of file size if we can do it by handle.
@@ -1003,49 +1002,22 @@ int cifs_setattr(struct dentry *direntry, struct iattr *attrs)
                    when the local oplock break takes longer to flush
                    writebehind data than the SMB timeout for the SetPathInfo
                    request would allow */
-                list_for_each(tmp, &cifsInode->openFileList) {
-                        open_file = list_entry(tmp, struct cifsFileInfo,
-                                               flist);
-                        /* We check if file is open for writing first */
-                        if ((open_file->pfile) &&
-                            ((open_file->pfile->f_flags & O_RDWR) ||
-                            (open_file->pfile->f_flags & O_WRONLY))) {
-                                if (open_file->invalidHandle == FALSE) {
-                                        /* we found a valid, writeable network
-                                           file handle to use to try to set the
-                                           file size */
-                                        __u16 nfid = open_file->netfid;
-                                        __u32 npid = open_file->pid;
-                                        read_unlock(&GlobalSMBSeslock);
-                                        found = TRUE;
-                                        rc = CIFSSMBSetFileSize(xid, pTcon,
-                                                attrs->ia_size, nfid, npid,
-                                                FALSE);
-                                        cFYI(1, ("SetFileSize by handle "
-                                                 "(setattrs) rc = %d", rc));
-                                        /* Do not need reopen and retry on
-                                           EAGAIN since we will retry by
-                                           pathname below */
-
-                                        /* now that we found one valid file
-                                           handle no sense continuing to loop
-                                           trying others, so break here */
-                                        if(rc == -EINVAL) {
-                                                int bytes_written;
-                                                rc = CIFSSMBWrite(xid, pTcon,
-                                                        nfid, 0,
-                                                        attrs->ia_size, 
-                                                        &bytes_written, NULL,
-                                                        NULL, 1 /* 45 sec */);
-                                                cFYI(1,("wrt seteof rc %d",rc));
-                                        }
-                                        break;
-                                }
+                open_file = find_writable_file(cifsInode);
+                if (open_file) {
+                        __u16 nfid = open_file->netfid;
+                        __u32 npid = open_file->pid;
+                        rc = CIFSSMBSetFileSize(xid, pTcon, attrs->ia_size,
+                                                nfid, npid, FALSE);
+                        cFYI(1,("SetFSize for attrs rc = %d", rc));
+                        if(rc == -EINVAL) {
+                                int bytes_written;
+                                rc = CIFSSMBWrite(xid, pTcon,
+                                                  nfid, 0, attrs->ia_size,
+                                                  &bytes_written, NULL, NULL,
+                                                  1 /* 45 seconds */);
+                                cFYI(1,("Wrt seteof rc %d", rc));
                         }
                 }
-                if (found == FALSE)
-                        read_unlock(&GlobalSMBSeslock);
-
                 if (rc != 0) {
                         /* Set file size by pathname rather than by handle
                            either because no valid, writeable file handle for