vfat: change the default from shortname=lower to shortname=mixed

[safe/jmp/linux-2.6] / Documentation / filesystems / Locking

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 76efe5b..18b9d0c 100644 (file)
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -109,27 +109,28 @@ prototypes:
 
 locking rules:
        All may block.
-                       BKL     s_lock  s_umount
-alloc_inode:           no      no      no
-destroy_inode:         no
-dirty_inode:           no                              (must not sleep)
-write_inode:           no
-drop_inode:            no                              !!!inode_lock!!!
-delete_inode:          no
-put_super:             yes     yes     no
-write_super:           no      yes     read
-sync_fs:               no      no      read
-freeze_fs:             ?
-unfreeze_fs:           ?
-statfs:                        no      no      no
-remount_fs:            yes     yes     maybe           (see below)
-clear_inode:           no
-umount_begin:          yes     no      no
-show_options:          no                              (vfsmount->sem)
-quota_read:            no      no      no              (see below)
-quota_write:           no      no      no              (see below)
-
-->remount_fs() will have the s_umount lock if it's already mounted.
+       None have BKL
+                       s_umount
+alloc_inode:
+destroy_inode:
+dirty_inode:                           (must not sleep)
+write_inode:
+drop_inode:                            !!!inode_lock!!!
+delete_inode:
+put_super:             write
+write_super:           read
+sync_fs:               read
+freeze_fs:             read
+unfreeze_fs:           read
+statfs:                        no
+remount_fs:            maybe           (see below)
+clear_inode:
+umount_begin:          no
+show_options:          no              (namespace_sem)
+quota_read:            no              (see below)
+quota_write:           no              (see below)
+
+->remount_fs() will have the s_umount exclusive lock if it's already mounted.
 When called from get_sb_single, it does NOT have the s_umount lock.
 ->quota_read() and ->quota_write() functions are both guaranteed to
 be the only ones operating on the quota file by the quota code (via
@@ -187,7 +188,7 @@ readpages:          no
 write_begin:           no      locks the page          yes
 write_end:             no      yes, unlocks            yes
 perform_write:         no      n/a                     yes
-bmap:                  yes
+bmap:                  no
 invalidatepage:                no      yes
 releasepage:           no      yes
 direct_IO:             no
@@ -512,16 +513,24 @@ 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