Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: make cifs_set_oplock_level() take a cifsInodeInfo pointer
  cifs: dereferencing first then checking
  cifs: trivial comment fix: tlink_tree is now a rbtree
  [CIFS] Cleanup unused variable build warning
  cifs: convert tlink_tree to a rbtree
  cifs: store pointer to master tlink in superblock (try #2)
  cifs: trivial doc fix: note setlease implemented
  CIFS: Add cifs_set_oplock_level
  FS: cifs, remove unneeded NULL tests

9 files changed, 152 insertions, 161 deletions

diff --git a/fs/cifs/TODO b/fs/cifs/TODO
index 5aff46c..355abcd 100644
--- a/fs/cifs/TODO
+++ b/fs/cifs/TODO
@@ -81,7 +81,7 @@ u) DOS attrs - returned as pseudo-xattr in Samba format (check VFAT and NTFS for
 
 v) mount check for unmatched uids
 
-w) Add support for new vfs entry points for setlease and fallocate 
+w) Add support for new vfs entry point for fallocate
 
 x) Fix Samba 3 server to handle Linux kernel aio so dbench with lots of 
 processes can proceed better in parallel (on the server)
diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index 525ba59..e9a393c 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -15,7 +15,7 @@
  *   the GNU Lesser General Public License for more details.
  *
  */
-#include <linux/radix-tree.h>
+#include <linux/rbtree.h>
 
 #ifndef _CIFS_FS_SB_H
 #define _CIFS_FS_SB_H
@@ -42,9 +42,9 @@
 #define CIFS_MOUNT_MULTIUSER	0x20000 /* multiuser mount */
 
 struct cifs_sb_info {
-	struct radix_tree_root tlink_tree;
-#define CIFS_TLINK_MASTER_TAG		0	/* is "master" (mount) tcon */
+	struct rb_root tlink_tree;
 	spinlock_t tlink_tree_lock;
+	struct tcon_link *master_tlink;
 	struct nls_table *local_nls;
 	unsigned int rsize;
 	unsigned int wsize;
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 75c4eaa..9c37897 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -116,7 +116,7 @@ cifs_read_super(struct super_block *sb, void *data,
 		return -ENOMEM;
 
 	spin_lock_init(&cifs_sb->tlink_tree_lock);
-	INIT_RADIX_TREE(&cifs_sb->tlink_tree, GFP_KERNEL);
+	cifs_sb->tlink_tree = RB_ROOT;
 
 	rc = bdi_setup_and_register(&cifs_sb->bdi, "cifs", BDI_CAP_MAP_COPY);
 	if (rc) {
@@ -321,8 +321,7 @@ cifs_alloc_inode(struct super_block *sb)
 	/* Until the file is open and we have gotten oplock
 	info back from the server, can not assume caching of
 	file data or metadata */
-	cifs_inode->clientCanCacheRead = false;
-	cifs_inode->clientCanCacheAll = false;
+	cifs_set_oplock_level(cifs_inode, 0);
 	cifs_inode->delete_pending = false;
 	cifs_inode->invalid_mapping = false;
 	cifs_inode->vfs_inode.i_blkbits = 14;  /* 2**14 = CIFS_MAX_MSGSIZE */
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index f259e4d..b577bf0 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -336,7 +336,8 @@ struct cifsTconInfo {
  * "get" on the container.
  */
 struct tcon_link {
-	unsigned long		tl_index;
+	struct rb_node		tl_rbnode;
+	uid_t			tl_uid;
 	unsigned long		tl_flags;
 #define TCON_LINK_MASTER	0
 #define TCON_LINK_PENDING	1
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index edb6d90..7ed69b6 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -104,6 +104,7 @@ extern struct timespec cifs_NTtimeToUnix(__le64 utc_nanoseconds_since_1601);
 extern u64 cifs_UnixTimeToNT(struct timespec);
 extern struct timespec cnvrtDosUnixTm(__le16 le_date, __le16 le_time,
 				      int offset);
+extern void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock);
 
 extern struct cifsFileInfo *cifs_new_fileinfo(__u16 fileHandle,
 				struct file *file, struct tcon_link *tlink,
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 9eb327d..251a17c 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -116,6 +116,7 @@ struct smb_vol {
 
 static int ipv4_connect(struct TCP_Server_Info *server);
 static int ipv6_connect(struct TCP_Server_Info *server);
+static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
 static void cifs_prune_tlinks(struct work_struct *work);
 
 /*
@@ -2900,24 +2901,16 @@ remote_path_check:
 		goto mount_fail_check;
 	}
 
-	tlink->tl_index = pSesInfo->linux_uid;
+	tlink->tl_uid = pSesInfo->linux_uid;
 	tlink->tl_tcon = tcon;
 	tlink->tl_time = jiffies;
 	set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
 	set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
 
-	rc = radix_tree_preload(GFP_KERNEL);
-	if (rc == -ENOMEM) {
-		kfree(tlink);
-		goto mount_fail_check;
-	}
-
+	cifs_sb->master_tlink = tlink;
 	spin_lock(&cifs_sb->tlink_tree_lock);
-	radix_tree_insert(&cifs_sb->tlink_tree, pSesInfo->linux_uid, tlink);
-	radix_tree_tag_set(&cifs_sb->tlink_tree, pSesInfo->linux_uid,
-			   CIFS_TLINK_MASTER_TAG);
+	tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
 	spin_unlock(&cifs_sb->tlink_tree_lock);
-	radix_tree_preload_end();
 
 	queue_delayed_work(system_nrt_wq, &cifs_sb->prune_tlinks,
 				TLINK_IDLE_EXPIRE);
@@ -3107,32 +3100,25 @@ CIFSTCon(unsigned int xid, struct cifsSesInfo *ses,
 int
 cifs_umount(struct super_block *sb, struct cifs_sb_info *cifs_sb)
 {
-	int i, ret;
+	struct rb_root *root = &cifs_sb->tlink_tree;
+	struct rb_node *node;
+	struct tcon_link *tlink;
 	char *tmp;
-	struct tcon_link *tlink[8];
-	unsigned long index = 0;
 
 	cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
 
-	do {
-		spin_lock(&cifs_sb->tlink_tree_lock);
-		ret = radix_tree_gang_lookup(&cifs_sb->tlink_tree,
-					     (void **)tlink, index,
-					     ARRAY_SIZE(tlink));
-		/* increment index for next pass */
-		if (ret > 0)
-			index = tlink[ret - 1]->tl_index + 1;
-		for (i = 0; i < ret; i++) {
-			cifs_get_tlink(tlink[i]);
-			clear_bit(TCON_LINK_IN_TREE, &tlink[i]->tl_flags);
-			radix_tree_delete(&cifs_sb->tlink_tree,
-							tlink[i]->tl_index);
-		}
-		spin_unlock(&cifs_sb->tlink_tree_lock);
+	spin_lock(&cifs_sb->tlink_tree_lock);
+	while ((node = rb_first(root))) {
+		tlink = rb_entry(node, struct tcon_link, tl_rbnode);
+		cifs_get_tlink(tlink);
+		clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
+		rb_erase(node, root);
 
-		for (i = 0; i < ret; i++)
-			cifs_put_tlink(tlink[i]);
-	} while (ret != 0);
+		spin_unlock(&cifs_sb->tlink_tree_lock);
+		cifs_put_tlink(tlink);
+		spin_lock(&cifs_sb->tlink_tree_lock);
+	}
+	spin_unlock(&cifs_sb->tlink_tree_lock);
 
 	tmp = cifs_sb->prepath;
 	cifs_sb->prepathlen = 0;
@@ -3271,22 +3257,10 @@ out:
 	return tcon;
 }
 
-static struct tcon_link *
+static inline struct tcon_link *
 cifs_sb_master_tlink(struct cifs_sb_info *cifs_sb)
 {
-	struct tcon_link *tlink;
-	unsigned int ret;
-
-	spin_lock(&cifs_sb->tlink_tree_lock);
-	ret = radix_tree_gang_lookup_tag(&cifs_sb->tlink_tree, (void **)&tlink,
-					0, 1, CIFS_TLINK_MASTER_TAG);
-	spin_unlock(&cifs_sb->tlink_tree_lock);
-
-	/* the master tcon should always be present */
-	if (ret == 0)
-		BUG();
-
-	return tlink;
+	return cifs_sb->master_tlink;
 }
 
 struct cifsTconInfo *
@@ -3302,6 +3276,47 @@ cifs_sb_tcon_pending_wait(void *unused)
 	return signal_pending(current) ? -ERESTARTSYS : 0;
 }
 
+/* find and return a tlink with given uid */
+static struct tcon_link *
+tlink_rb_search(struct rb_root *root, uid_t uid)
+{
+	struct rb_node *node = root->rb_node;
+	struct tcon_link *tlink;
+
+	while (node) {
+		tlink = rb_entry(node, struct tcon_link, tl_rbnode);
+
+		if (tlink->tl_uid > uid)
+			node = node->rb_left;
+		else if (tlink->tl_uid < uid)
+			node = node->rb_right;
+		else
+			return tlink;
+	}
+	return NULL;
+}
+
+/* insert a tcon_link into the tree */
+static void
+tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
+{
+	struct rb_node **new = &(root->rb_node), *parent = NULL;
+	struct tcon_link *tlink;
+
+	while (*new) {
+		tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
+		parent = *new;
+
+		if (tlink->tl_uid > new_tlink->tl_uid)
+			new = &((*new)->rb_left);
+		else
+			new = &((*new)->rb_right);
+	}
+
+	rb_link_node(&new_tlink->tl_rbnode, parent, new);
+	rb_insert_color(&new_tlink->tl_rbnode, root);
+}
+
 /*
  * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
  * current task.
@@ -3309,7 +3324,7 @@ cifs_sb_tcon_pending_wait(void *unused)
  * If the superblock doesn't refer to a multiuser mount, then just return
  * the master tcon for the mount.
  *
- * First, search the radix tree for an existing tcon for this fsuid. If one
+ * First, search the rbtree for an existing tcon for this fsuid. If one
  * exists, then check to see if it's pending construction. If it is then wait
  * for construction to complete. Once it's no longer pending, check to see if
  * it failed and either return an error or retry construction, depending on
@@ -3322,14 +3337,14 @@ struct tcon_link *
 cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
 {
 	int ret;
-	unsigned long fsuid = (unsigned long) current_fsuid();
+	uid_t fsuid = current_fsuid();
 	struct tcon_link *tlink, *newtlink;
 
 	if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
 		return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
 
 	spin_lock(&cifs_sb->tlink_tree_lock);
-	tlink = radix_tree_lookup(&cifs_sb->tlink_tree, fsuid);
+	tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
 	if (tlink)
 		cifs_get_tlink(tlink);
 	spin_unlock(&cifs_sb->tlink_tree_lock);
@@ -3338,36 +3353,24 @@ cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
 		newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
 		if (newtlink == NULL)
 			return ERR_PTR(-ENOMEM);
-		newtlink->tl_index = fsuid;
+		newtlink->tl_uid = fsuid;
 		newtlink->tl_tcon = ERR_PTR(-EACCES);
 		set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
 		set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
 		cifs_get_tlink(newtlink);
 
-		ret = radix_tree_preload(GFP_KERNEL);
-		if (ret != 0) {
-			kfree(newtlink);
-			return ERR_PTR(ret);
-		}
-
 		spin_lock(&cifs_sb->tlink_tree_lock);
 		/* was one inserted after previous search? */
-		tlink = radix_tree_lookup(&cifs_sb->tlink_tree, fsuid);
+		tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
 		if (tlink) {
 			cifs_get_tlink(tlink);
 			spin_unlock(&cifs_sb->tlink_tree_lock);
-			radix_tree_preload_end();
 			kfree(newtlink);
 			goto wait_for_construction;
 		}
-		ret = radix_tree_insert(&cifs_sb->tlink_tree, fsuid, newtlink);
-		spin_unlock(&cifs_sb->tlink_tree_lock);
-		radix_tree_preload_end();
-		if (ret) {
-			kfree(newtlink);
-			return ERR_PTR(ret);
-		}
 		tlink = newtlink;
+		tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
+		spin_unlock(&cifs_sb->tlink_tree_lock);
 	} else {
 wait_for_construction:
 		ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
@@ -3413,39 +3416,39 @@ cifs_prune_tlinks(struct work_struct *work)
 {
 	struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
 						    prune_tlinks.work);
-	struct tcon_link *tlink[8];
-	unsigned long now = jiffies;
-	unsigned long index = 0;
-	int i, ret;
+	struct rb_root *root = &cifs_sb->tlink_tree;
+	struct rb_node *node = rb_first(root);
+	struct rb_node *tmp;
+	struct tcon_link *tlink;
 
-	do {
-		spin_lock(&cifs_sb->tlink_tree_lock);
-		ret = radix_tree_gang_lookup(&cifs_sb->tlink_tree,
-					     (void **)tlink, index,
-					     ARRAY_SIZE(tlink));
-		/* increment index for next pass */
-		if (ret > 0)
-			index = tlink[ret - 1]->tl_index + 1;
-		for (i = 0; i < ret; i++) {
-			if (test_bit(TCON_LINK_MASTER, &tlink[i]->tl_flags) ||
-			    atomic_read(&tlink[i]->tl_count) != 0 ||
-			    time_after(tlink[i]->tl_time + TLINK_IDLE_EXPIRE,
-				       now)) {
-				tlink[i] = NULL;
-				continue;
-			}
-			cifs_get_tlink(tlink[i]);
-			clear_bit(TCON_LINK_IN_TREE, &tlink[i]->tl_flags);
-			radix_tree_delete(&cifs_sb->tlink_tree,
-					  tlink[i]->tl_index);
-		}
-		spin_unlock(&cifs_sb->tlink_tree_lock);
+	/*
+	 * Because we drop the spinlock in the loop in order to put the tlink
+	 * it's not guarded against removal of links from the tree. The only
+	 * places that remove entries from the tree are this function and
+	 * umounts. Because this function is non-reentrant and is canceled
+	 * before umount can proceed, this is safe.
+	 */
+	spin_lock(&cifs_sb->tlink_tree_lock);
+	node = rb_first(root);
+	while (node != NULL) {
+		tmp = node;
+		node = rb_next(tmp);
+		tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
+
+		if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
+		    atomic_read(&tlink->tl_count) != 0 ||
+		    time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
+			continue;
 
-		for (i = 0; i < ret; i++) {
-			if (tlink[i] != NULL)
-				cifs_put_tlink(tlink[i]);
-		}
-	} while (ret != 0);
+		cifs_get_tlink(tlink);
+		clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
+		rb_erase(tmp, root);
+
+		spin_unlock(&cifs_sb->tlink_tree_lock);
+		cifs_put_tlink(tlink);
+		spin_lock(&cifs_sb->tlink_tree_lock);
+	}
+	spin_unlock(&cifs_sb->tlink_tree_lock);
 
 	queue_delayed_work(system_nrt_wq, &cifs_sb->prune_tlinks,
 				TLINK_IDLE_EXPIRE);
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index ae82159..06c3e83 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -146,12 +146,7 @@ client_can_cache:
 		rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
 					 xid, NULL);
 
-	if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
-		pCifsInode->clientCanCacheAll = true;
-		pCifsInode->clientCanCacheRead = true;
-		cFYI(1, "Exclusive Oplock granted on inode %p", inode);
-	} else if ((oplock & 0xF) == OPLOCK_READ)
-		pCifsInode->clientCanCacheRead = true;
+	cifs_set_oplock_level(pCifsInode, oplock);
 
 	return rc;
 }
@@ -253,12 +248,7 @@ cifs_new_fileinfo(__u16 fileHandle, struct file *file,
 		list_add_tail(&pCifsFile->flist, &pCifsInode->openFileList);
 	spin_unlock(&cifs_file_list_lock);
 
-	if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
-		pCifsInode->clientCanCacheAll = true;
-		pCifsInode->clientCanCacheRead = true;
-		cFYI(1, "Exclusive Oplock inode %p", inode);
-	} else if ((oplock & 0xF) == OPLOCK_READ)
-		pCifsInode->clientCanCacheRead = true;
+	cifs_set_oplock_level(pCifsInode, oplock);
 
 	file->private_data = pCifsFile;
 	return pCifsFile;
@@ -271,8 +261,9 @@ cifs_new_fileinfo(__u16 fileHandle, struct file *file,
  */
 void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
 {
+	struct inode *inode = cifs_file->dentry->d_inode;
 	struct cifsTconInfo *tcon = tlink_tcon(cifs_file->tlink);
-	struct cifsInodeInfo *cifsi = CIFS_I(cifs_file->dentry->d_inode);
+	struct cifsInodeInfo *cifsi = CIFS_I(inode);
 	struct cifsLockInfo *li, *tmp;
 
 	spin_lock(&cifs_file_list_lock);
@@ -288,8 +279,7 @@ void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
 	if (list_empty(&cifsi->openFileList)) {
 		cFYI(1, "closing last open instance for inode %p",
 			cifs_file->dentry->d_inode);
-		cifsi->clientCanCacheRead = false;
-		cifsi->clientCanCacheAll  = false;
+		cifs_set_oplock_level(cifsi, 0);
 	}
 	spin_unlock(&cifs_file_list_lock);
 
@@ -607,8 +597,6 @@ reopen_success:
 		rc = filemap_write_and_wait(inode->i_mapping);
 		mapping_set_error(inode->i_mapping, rc);
 
-		pCifsInode->clientCanCacheAll = false;
-		pCifsInode->clientCanCacheRead = false;
 		if (tcon->unix_ext)
 			rc = cifs_get_inode_info_unix(&inode,
 				full_path, inode->i_sb, xid);
@@ -622,18 +610,9 @@ reopen_success:
 	     invalidate the current end of file on the server
 	     we can not go to the server to get the new inod
 	     info */
-	if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
-		pCifsInode->clientCanCacheAll = true;
-		pCifsInode->clientCanCacheRead = true;
-		cFYI(1, "Exclusive Oplock granted on inode %p",
-			 pCifsFile->dentry->d_inode);
-	} else if ((oplock & 0xF) == OPLOCK_READ) {
-		pCifsInode->clientCanCacheRead = true;
-		pCifsInode->clientCanCacheAll = false;
-	} else {
-		pCifsInode->clientCanCacheRead = false;
-		pCifsInode->clientCanCacheAll = false;
-	}
+
+	cifs_set_oplock_level(pCifsInode, oplock);
+
 	cifs_relock_file(pCifsFile);
 
 reopen_error_exit:
@@ -775,12 +754,6 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
 
 	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 	tcon = tlink_tcon(((struct cifsFileInfo *)file->private_data)->tlink);
-
-	if (file->private_data == NULL) {
-		rc = -EBADF;
-		FreeXid(xid);
-		return rc;
-	}
 	netfid = ((struct cifsFileInfo *)file->private_data)->netfid;
 
 	if ((tcon->ses->capabilities & CAP_UNIX) &&
@@ -956,6 +929,7 @@ cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
 ssize_t cifs_user_write(struct file *file, const char __user *write_data,
 	size_t write_size, loff_t *poffset)
 {
+	struct inode *inode = file->f_path.dentry->d_inode;
 	int rc = 0;
 	unsigned int bytes_written = 0;
 	unsigned int total_written;
@@ -963,7 +937,7 @@ ssize_t cifs_user_write(struct file *file, const char __user *write_data,
 	struct cifsTconInfo *pTcon;
 	int xid, long_op;
 	struct cifsFileInfo *open_file;
-	struct cifsInodeInfo *cifsi = CIFS_I(file->f_path.dentry->d_inode);
+	struct cifsInodeInfo *cifsi = CIFS_I(inode);
 
 	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 
@@ -1029,21 +1003,17 @@ ssize_t cifs_user_write(struct file *file, const char __user *write_data,
 
 	cifs_stats_bytes_written(pTcon, total_written);
 
-	/* since the write may have blocked check these pointers again */
-	if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) {
-		struct inode *inode = file->f_path.dentry->d_inode;
 /* Do not update local mtime - server will set its actual value on write
- *		inode->i_ctime = inode->i_mtime =
- * 			current_fs_time(inode->i_sb);*/
-		if (total_written > 0) {
-			spin_lock(&inode->i_lock);
-			if (*poffset > file->f_path.dentry->d_inode->i_size)
-				i_size_write(file->f_path.dentry->d_inode,
-					*poffset);
-			spin_unlock(&inode->i_lock);
-		}
-		mark_inode_dirty_sync(file->f_path.dentry->d_inode);
+ *	inode->i_ctime = inode->i_mtime =
+ * 		current_fs_time(inode->i_sb);*/
+	if (total_written > 0) {
+		spin_lock(&inode->i_lock);
+		if (*poffset > inode->i_size)
+			i_size_write(inode, *poffset);
+		spin_unlock(&inode->i_lock);
 	}
+	mark_inode_dirty_sync(inode);
+
 	FreeXid(xid);
 	return total_written;
 }
@@ -1178,7 +1148,7 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
 					bool fsuid_only)
 {
 	struct cifsFileInfo *open_file;
-	struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
+	struct cifs_sb_info *cifs_sb;
 	bool any_available = false;
 	int rc;
 
@@ -1192,6 +1162,8 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
 		return NULL;
 	}
 
+	cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
+
 	/* only filter by fsuid on multiuser mounts */
 	if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
 		fsuid_only = false;
diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
index 077bf75..2fa22f2 100644
--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -63,8 +63,6 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 #ifdef CONFIG_CIFS_POSIX
 		case FS_IOC_GETFLAGS:
 			if (CIFS_UNIX_EXTATTR_CAP & caps) {
-				if (pSMBFile == NULL)
-					break;
 				rc = CIFSGetExtAttr(xid, tcon, pSMBFile->netfid,
 					&ExtAttrBits, &ExtAttrMask);
 				if (rc == 0)
@@ -80,8 +78,6 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 					rc = -EFAULT;
 					break;
 				}
-				if (pSMBFile == NULL)
-					break;
 				/* rc= CIFSGetExtAttr(xid,tcon,pSMBFile->netfid,
 					extAttrBits, &ExtAttrMask);*/
 			}
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index c4e296f..43f1028 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -569,10 +569,9 @@ is_valid_oplock_break(struct smb_hdr *buf, struct TCP_Server_Info *srv)
 
 				cFYI(1, "file id match, oplock break");
 				pCifsInode = CIFS_I(netfile->dentry->d_inode);
-				pCifsInode->clientCanCacheAll = false;
-				if (pSMB->OplockLevel == 0)
-					pCifsInode->clientCanCacheRead = false;
 
+				cifs_set_oplock_level(pCifsInode,
+						      pSMB->OplockLevel);
 				/*
 				 * cifs_oplock_break_put() can't be called
 				 * from here.  Get reference after queueing
@@ -722,3 +721,23 @@ cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
 			   cifs_sb_master_tcon(cifs_sb)->treeName);
 	}
 }
+
+void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
+{
+	oplock &= 0xF;
+
+	if (oplock == OPLOCK_EXCLUSIVE) {
+		cinode->clientCanCacheAll = true;
+		cinode->clientCanCacheRead = true;
+		cFYI(1, "Exclusive Oplock granted on inode %p",
+		     &cinode->vfs_inode);
+	} else if (oplock == OPLOCK_READ) {
+		cinode->clientCanCacheAll = false;
+		cinode->clientCanCacheRead = true;
+		cFYI(1, "Level II Oplock granted on inode %p",
+		    &cinode->vfs_inode);
+	} else {
+		cinode->clientCanCacheAll = false;
+		cinode->clientCanCacheRead = false;
+	}
+}