linux-disable-readahad-20081108

LICENSE IPL10
FIXES 123604

The code has long contained a backing_dev_info structure, but it
was never attached to anything.  Initialize its use properly with
bdi_init, and attach it to i_mapping for every newly filled inode.
bdi_init and bdi_destroy are needed for proper initialization of
some percpu counters, otherwise we get some oopses.

diff --git a/acinclude.m4 b/acinclude.m4
index 9d3f48fd8c6e2034b2df9d8033b631d13b000344..319c5fed78bd611815fffcca4d1969be48e02603 100644 (file)
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -811,6 +811,7 @@ case $AFS_SYSNAME in *_linux* | *_umlinux*)
                 LINUX_EXPORTS_FIND_TASK_BY_PID
                 LINUX_EXPORTS_PROC_ROOT_FS
                  LINUX_HAVE_CURRENT_KERNEL_TIME
+                 LINUX_HAVE_BDI_INIT
                  LINUX_KMEM_CACHE_INIT
                 LINUX_HAVE_KMEM_CACHE_T
                 LINUX_KMEM_CACHE_CREATE_TAKES_DTOR

diff --git a/src/afs/LINUX/osi_vfsops.c b/src/afs/LINUX/osi_vfsops.c
index 84196250b63adf1278dab09b5b9b103e2a05913a..5cf5d55cdb31dcd7be18b31e4d872bfa3f88470b 100644 (file)
--- a/src/afs/LINUX/osi_vfsops.c
+++ b/src/afs/LINUX/osi_vfsops.c
@@ -146,6 +146,9 @@ afs_read_super(struct super_block *sb, void *data, int silent)
     sb->s_blocksize_bits = 10;
     sb->s_magic = AFS_VFSMAGIC;
     sb->s_op = &afs_sops;      /* Super block (vfs) ops */
+#if defined(HAVE_BDI_INIT)
+    bdi_init(&afs_backing_dev_info);
+#endif
 #if defined(AFS_LINUX26_ENV) && !defined(AFS_NONFSTRANS)
     sb->s_export_op = &afs_export_ops;
 #endif
@@ -400,6 +403,9 @@ afs_put_super(struct super_block *sbp)
 #endif
 
     osi_linux_verify_alloced_memory();
+#if defined(HAVE_BDI_INIT)
+    bdi_destroy(&afs_backing_dev_info);
+#endif
     AFS_GUNLOCK();
 
     sbp->s_dev = 0;

diff --git a/src/afs/LINUX/osi_vnodeops.c b/src/afs/LINUX/osi_vnodeops.c
index 804770d7054cee16090b0ae7cf173a122026b4d3..bb3e499d725b541ac29c684100111159caf79729 100644 (file)
--- a/src/afs/LINUX/osi_vnodeops.c
+++ b/src/afs/LINUX/osi_vnodeops.c
@@ -53,6 +53,7 @@ RCSID
 #if defined(AFS_LINUX26_ENV)
 #define LockPage(pp) lock_page(pp)
 #define UnlockPage(pp) unlock_page(pp)
+extern struct backing_dev_info afs_backing_dev_info;
 #endif
 
 extern struct vcache *afs_globalVp;
@@ -2231,6 +2232,7 @@ afs_fill_inode(struct inode *ip, struct vattr *vattr)
     if (vattr)
        vattr2inode(ip, vattr);
 
+    ip->i_mapping->backing_dev_info = &afs_backing_dev_info;
 /* Reset ops if symlink or directory. */
     if (S_ISREG(ip->i_mode)) {
        ip->i_op = &afs_file_iops;

diff --git a/src/cf/linux-test4.m4 b/src/cf/linux-test4.m4
index af278de98017465fca5eb7e999f50299b826fd3c..1d9546102ee6a7509127e31cd1103fe7fda647d7 100644 (file)
--- a/src/cf/linux-test4.m4
+++ b/src/cf/linux-test4.m4
@@ -1092,3 +1092,15 @@ AC_DEFUN([LINUX_SEMAPHORE_H_EXISTS], [
     AC_DEFINE([LINUX_SEMAPHORE_H], 1, [define if linux/semaphore.h exists])
   fi])
 
+AC_DEFUN([LINUX_HAVE_BDI_INIT], [
+  AC_MSG_CHECKING([for linux bdi_init()])
+  AC_CACHE_VAL([ac_cv_linux_bdi_init], [
+    AC_TRY_KBUILD(
+[#include <linux/backing-dev.h>],
+[bdi_init(NULL);],
+      ac_cv_linux_bdi_init=yes,
+      ac_cv_linux_bdi_init=no)])
+  AC_MSG_RESULT($ac_cv_linux_bdi_init)
+  if test "x$ac_cv_linux_bdi_init" = "xyes"; then
+    AC_DEFINE([HAVE_BDI_INIT], 1, [define if your kernel has a bdi_init()])
+  fi])