Merge commit 'v2.6.30' into for-2.6.31

This commit is contained in:
J. Bruce Fields
2009-06-15 18:08:07 -07:00
1647 changed files with 42867 additions and 29314 deletions

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@ -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

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@ -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).

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@ -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