X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=fs%2Fopen.c;h=a7719cfb7257e9b19b2ff50efeb5366f98f4d24b;hb=5114a97a8bce7f4ead29a32b67dee85438699b9e;hp=4fd6e256f4f454e0e8792d1a11c44e377dfbae04;hpb=575f9c43e709ab5008047eb5c68b99fe04592400;p=cascardo%2Flinux.git

diff --git a/fs/open.c b/fs/open.c
index 4fd6e256f4f4..a7719cfb7257 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -68,6 +68,7 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
 long vfs_truncate(const struct path *path, loff_t length)
 {
 	struct inode *inode;
+	struct dentry *upperdentry;
 	long error;
 
 	inode = path->dentry->d_inode;
@@ -90,7 +91,17 @@ long vfs_truncate(const struct path *path, loff_t length)
 	if (IS_APPEND(inode))
 		goto mnt_drop_write_and_out;
 
-	error = get_write_access(inode);
+	/*
+	 * If this is an overlayfs then do as if opening the file so we get
+	 * write access on the upper inode, not on the overlay inode.  For
+	 * non-overlay filesystems d_real() is an identity function.
+	 */
+	upperdentry = d_real(path->dentry, NULL, O_WRONLY);
+	error = PTR_ERR(upperdentry);
+	if (IS_ERR(upperdentry))
+		goto mnt_drop_write_and_out;
+
+	error = get_write_access(upperdentry->d_inode);
 	if (error)
 		goto mnt_drop_write_and_out;
 
@@ -109,7 +120,7 @@ long vfs_truncate(const struct path *path, loff_t length)
 		error = do_truncate(path->dentry, length, 0, NULL);
 
 put_write_and_out:
-	put_write_access(inode);
+	put_write_access(upperdentry->d_inode);
 mnt_drop_write_and_out:
 	mnt_drop_write(path->mnt);
 out:
@@ -289,7 +300,8 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 	 * Let individual file system decide if it supports preallocation
 	 * for directories or not.
 	 */
-	if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
+	if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode) &&
+	    !S_ISBLK(inode->i_mode))
 		return -ENODEV;
 
 	/* Check for wrap through zero too */
@@ -726,7 +738,7 @@ static int do_dentry_open(struct file *f,
 	if (error)
 		goto cleanup_all;
 
-	error = break_lease(inode, f->f_flags);
+	error = break_lease(locks_inode(f), f->f_flags);
 	if (error)
 		goto cleanup_all;