Return -EOPNOTSUPP for ZFS_IOC_{GET|SET}FLAGS

[zfs.git] / module / zfs / zpl_file.c

diff --git a/module/zfs/zpl_file.c b/module/zfs/zpl_file.c
index 5ac41c9..c6d97db 100644 (file)
--- a/module/zfs/zpl_file.c
+++ b/module/zfs/zpl_file.c
@@ -357,21 +357,16 @@ zpl_putpage(struct page *pp, struct writeback_control *wbc, void *data)
 
        ASSERT(PageLocked(pp));
        ASSERT(!PageWriteback(pp));
+       ASSERT(!(current->flags & PF_NOFS));
 
        /*
-        * Disable the normal reclaim path for zpl_putpage().  This
-        * ensures that all memory allocations under this call path
-        * will never enter direct reclaim.  If this were to happen
-        * the VM might try to write out additional pages by calling
-        * zpl_putpage() again resulting in a deadlock.
+        * Annotate this call path with a flag that indicates that it is
+        * unsafe to use KM_SLEEP during memory allocations due to the
+        * potential for a deadlock.  KM_PUSHPAGE should be used instead.
         */
-       if (current->flags & PF_MEMALLOC) {
-               (void) zfs_putpage(mapping->host, pp, wbc);
-       } else {
-               current->flags |= PF_MEMALLOC;
-               (void) zfs_putpage(mapping->host, pp, wbc);
-               current->flags &= ~PF_MEMALLOC;
-       }
+       current->flags |= PF_NOFS;
+       (void) zfs_putpage(mapping->host, pp, wbc);
+       current->flags &= ~PF_NOFS;
 
        return (0);
 }
@@ -438,6 +433,27 @@ zpl_fallocate(struct file *filp, int mode, loff_t offset, loff_t len)
 }
 #endif /* HAVE_FILE_FALLOCATE */
 
+static long
+zpl_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+       switch (cmd) {
+       case ZFS_IOC_GETFLAGS:
+       case ZFS_IOC_SETFLAGS:
+               return (-EOPNOTSUPP);
+       default:
+               return (-ENOTTY);
+       }
+}
+
+#ifdef CONFIG_COMPAT
+static long
+zpl_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+       return zpl_ioctl(filp, cmd, arg);
+}
+#endif /* CONFIG_COMPAT */
+
+
 const struct address_space_operations zpl_address_space_operations = {
        .readpages      = zpl_readpages,
        .readpage       = zpl_readpage,
@@ -451,12 +467,15 @@ const struct file_operations zpl_file_operations = {
        .llseek         = generic_file_llseek,
        .read           = zpl_read,
        .write          = zpl_write,
-       .readdir        = zpl_readdir,
        .mmap           = zpl_mmap,
        .fsync          = zpl_fsync,
 #ifdef HAVE_FILE_FALLOCATE
        .fallocate      = zpl_fallocate,
 #endif /* HAVE_FILE_FALLOCATE */
+       .unlocked_ioctl = zpl_ioctl,
+#ifdef CONFIG_COMPAT
+       .compat_ioctl   = zpl_compat_ioctl,
+#endif
 };
 
 const struct file_operations zpl_dir_file_operations = {
@@ -464,4 +483,8 @@ const struct file_operations zpl_dir_file_operations = {
        .read           = generic_read_dir,
        .readdir        = zpl_readdir,
        .fsync          = zpl_fsync,
+       .unlocked_ioctl = zpl_ioctl,
+#ifdef CONFIG_COMPAT
+       .compat_ioctl   = zpl_compat_ioctl,
+#endif
 };