Merge commit 'v2.6.30-rc5' into x86/mm

Merge reason: this branch was on a .30-rc2 base - sync it up with
              all the latest fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 21 insertions, 14 deletions

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 76efe5b71d7d..3120f8dd2c31 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -512,16 +512,24 @@ locking rules:
 		BKL	mmap_sem	PageLocked(page)
 open:		no	yes
 close:		no	yes
-fault:		no	yes
-page_mkwrite:	no	yes		no
+fault:		no	yes		can return with page locked
+page_mkwrite:	no	yes		can return with page locked
 access:		no	yes
 
-	->page_mkwrite() is called when a previously read-only page is
-about to become writeable. The file system is responsible for
-protecting against truncate races. Once appropriate action has been
-taking to lock out truncate, the page range should be verified to be
-within i_size. The page mapping should also be checked that it is not
-NULL.
+	->fault() is called when a previously not present pte is about
+to be faulted in. The filesystem must find and return the page associated
+with the passed in "pgoff" in the vm_fault structure. If it is possible that
+the page may be truncated and/or invalidated, then the filesystem must lock
+the page, then ensure it is not already truncated (the page lock will block
+subsequent truncate), and then return with VM_FAULT_LOCKED, and the page
+locked. The VM will unlock the page.
+
+	->page_mkwrite() is called when a previously read-only pte is
+about to become writeable. The filesystem again must ensure that there are
+no truncate/invalidate races, and then return with the page locked. If
+the page has been truncated, the filesystem should not look up a new page
+like the ->fault() handler, but simply return with VM_FAULT_NOPAGE, which
+will cause the VM to retry the fault.
 
 	->access() is called when get_user_pages() fails in
 acces_process_vm(), typically used to debug a process through
diff --git a/Documentation/filesystems/caching/cachefiles.txt b/Documentation/filesystems/caching/cachefiles.txt
index c78a49b7bba6..748a1ae49e12 100644
--- a/Documentation/filesystems/caching/cachefiles.txt
+++ b/Documentation/filesystems/caching/cachefiles.txt
@@ -407,7 +407,7 @@ A NOTE ON SECURITY
 ==================
 
 CacheFiles makes use of the split security in the task_struct.  It allocates
-its own task_security structure, and redirects current->act_as to point to it
+its own task_security structure, and redirects current->cred to point to it
 when it acts on behalf of another process, in that process's context.
 
 The reason it does this is that it calls vfs_mkdir() and suchlike rather than
@@ -429,9 +429,9 @@ This means it may lose signals or ptrace events for example, and affects what
 the process looks like in /proc.
 
 So CacheFiles makes use of a logical split in the security between the
-objective security (task->sec) and the subjective security (task->act_as).  The
-objective security holds the intrinsic security properties of a process and is
-never overridden.  This is what appears in /proc, and is what is used when a
+objective security (task->real_cred) and the subjective security (task->cred).
+The objective security holds the intrinsic security properties of a process and
+is never overridden.  This is what appears in /proc, and is what is used when a
 process is the target of an operation by some other process (SIGKILL for
 example).
 
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index deeeed0faa8f..f49eecf2e573 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -277,8 +277,7 @@ or bottom half).
   unfreeze_fs: called when VFS is unlocking a filesystem and making it writable
   	again.
 
-  statfs: called when the VFS needs to get filesystem statistics. This
-	is called with the kernel lock held
+  statfs: called when the VFS needs to get filesystem statistics.
 
   remount_fs: called when the filesystem is remounted. This is called
 	with the kernel lock held