fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ioctls

This patch adds ioctls to vfs for compatibility with legacy XFS
pre-allocation ioctls (XFS_IOC_*RESVP*). The implementation
effectively invokes sys_fallocate for the new ioctls.
Also handles the compat_ioctl case.
Note: These legacy ioctls are also implemented by OCFS2.

[AV: folded fixes from hch]

Signed-off-by: Ankit Jain <me@ankitjain.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 29 insertions, 29 deletions

diff --git a/fs/open.c b/fs/open.c
index 7200e23d9258..dd98e8076024 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -378,63 +378,63 @@ SYSCALL_ALIAS(sys_ftruncate64, SyS_ftruncate64);
 #endif
 #endif /* BITS_PER_LONG == 32 */
 
-SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len)
+
+int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 {
-        struct file *file;
-        struct inode *inode;
-        long ret = -EINVAL;
+        struct inode *inode = file->f_path.dentry->d_inode;
+        long ret;
 
         if (offset < 0 || len <= 0)
-                goto out;
+                return -EINVAL;
 
         /* Return error if mode is not supported */
-        ret = -EOPNOTSUPP;
         if (mode && !(mode & FALLOC_FL_KEEP_SIZE))
-                goto out;
+                return -EOPNOTSUPP;
 
-        ret = -EBADF;
-        file = fget(fd);
-        if (!file)
-                goto out;
         if (!(file->f_mode & FMODE_WRITE))
-                goto out_fput;
+                return -EBADF;
         /*
          * Revalidate the write permissions, in case security policy has
          * changed since the files were opened.
          */
         ret = security_file_permission(file, MAY_WRITE);
         if (ret)
-                goto out_fput;
+                return ret;
 
-        inode = file->f_path.dentry->d_inode;
-
-        ret = -ESPIPE;
         if (S_ISFIFO(inode->i_mode))
-                goto out_fput;
+                return -ESPIPE;
 
-        ret = -ENODEV;
         /*
          * Let individual file system decide if it supports preallocation
          * for directories or not.
          */
         if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
-                goto out_fput;
+                return -ENODEV;
 
-        ret = -EFBIG;
         /* Check for wrap through zero too */
         if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0))
-                goto out_fput;
+                return -EFBIG;
 
-        if (inode->i_op->fallocate)
-                ret = inode->i_op->fallocate(inode, mode, offset, len);
-        else
-                ret = -EOPNOTSUPP;
+        if (!inode->i_op->fallocate)
+                return -EOPNOTSUPP;
 
-out_fput:
-        fput(file);
-out:
-        return ret;
+        return inode->i_op->fallocate(inode, mode, offset, len);
 }
+
+SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len)
+{
+        struct file *file;
+        int error = -EBADF;
+
+        file = fget(fd);
+        if (file) {
+                error = do_fallocate(file, mode, offset, len);
+                fput(file);
+        }
+
+        return error;
+}
+
 #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
 asmlinkage long SyS_fallocate(long fd, long mode, loff_t offset, loff_t len)
 {