config/kernel-vfs-iterate.m4

   1 AC_DEFUN([ZFS_AC_KERNEL_SRC_VFS_ITERATE], [
   2         ZFS_LINUX_TEST_SRC([file_operations_iterate_shared], [
   3                 #include <linux/fs.h>
   4                 int iterate(struct file *filp, struct dir_context * context)
   5                     { return 0; }
   6
   7                 static const struct file_operations fops
   8                     __attribute__ ((unused)) = {
   9                         .iterate_shared  = iterate,
  10                 };
  11         ],[])
  12
  13         ZFS_LINUX_TEST_SRC([file_operations_iterate], [
  14                 #include <linux/fs.h>
  15                 int iterate(struct file *filp,
  16                     struct dir_context *context) { return 0; }
  17
  18                 static const struct file_operations fops
  19                     __attribute__ ((unused)) = {
  20                         .iterate         = iterate,
  21                 };
  22
  23                 #if defined(FMODE_KABI_ITERATE)
  24                 #error "RHEL 7.5, FMODE_KABI_ITERATE interface"
  25                 #endif
  26         ],[])
  27
  28         ZFS_LINUX_TEST_SRC([file_operations_readdir], [
  29                 #include <linux/fs.h>
  30                 int readdir(struct file *filp, void *entry,
  31                     filldir_t func) { return 0; }
  32
  33                 static const struct file_operations fops
  34                     __attribute__ ((unused)) = {
  35                         .readdir = readdir,
  36                 };
  37         ],[])
  38 ])
  39
  40 AC_DEFUN([ZFS_AC_KERNEL_VFS_ITERATE], [
  41         dnl #
  42         dnl # 4.7 API change
  43         dnl #
  44         AC_MSG_CHECKING([whether fops->iterate_shared() is available])
  45         ZFS_LINUX_TEST_RESULT([file_operations_iterate_shared], [
  46                 AC_MSG_RESULT(yes)
  47                 AC_DEFINE(HAVE_VFS_ITERATE_SHARED, 1,
  48                     [fops->iterate_shared() is available])
  49         ],[
  50                 AC_MSG_RESULT(no)
  51
  52                 dnl #
  53                 dnl # 3.11 API change
  54                 dnl #
  55                 dnl # RHEL 7.5 compatibility; the fops.iterate() method was
  56                 dnl # added to the file_operations structure but in order to
  57                 dnl # maintain KABI compatibility all callers must set
  58                 dnl # FMODE_KABI_ITERATE which is checked in iterate_dir().
  59                 dnl # When detected ignore this interface and fallback to
  60                 dnl # to using fops.readdir() to retain KABI compatibility.
  61                 dnl #
  62                 AC_MSG_CHECKING([whether fops->iterate() is available])
  63                 ZFS_LINUX_TEST_RESULT([file_operations_iterate], [
  64                         AC_MSG_RESULT(yes)
  65                         AC_DEFINE(HAVE_VFS_ITERATE, 1,
  66                             [fops->iterate() is available])
  67                 ],[
  68                         AC_MSG_RESULT(no)
  69
  70                         dnl #
  71                         dnl # readdir interface introduced
  72                         dnl #
  73                         AC_MSG_CHECKING([whether fops->readdir() is available])
  74                         ZFS_LINUX_TEST_RESULT([file_operations_readdir], [
  75                                 AC_MSG_RESULT(yes)
  76                                 AC_DEFINE(HAVE_VFS_READDIR, 1,
  77                                     [fops->readdir() is available])
  78                         ],[
  79                                 ZFS_LINUX_TEST_ERROR([vfs_iterate])
  80                         ])
  81                 ])
  82         ])
  83 ])