Merge commit 'v2.6.30' into for-2.6.31

3 files changed, 21 insertions, 13 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/tmpfs.txt b/Documentation/filesystems/tmpfs.txt
index 222437efd75a..3015da0c6b2a 100644
--- a/Documentation/filesystems/tmpfs.txt
+++ b/Documentation/filesystems/tmpfs.txt
@@ -133,4 +133,4 @@ RAM/SWAP in 10240 inodes and it is only accessible by root.
 Author:
    Christoph Rohland <cr@sap.com>, 1.12.01
 Updated:
-   Hugh Dickins <hugh@veritas.com>, 4 June 2007
+   Hugh Dickins, 4 June 2007