Merge with 2.4.0-test3-pre7.

3 files changed, 690 insertions, 28 deletions

diff --git a/Documentation/DocBook/parportbook.tmpl b/Documentation/DocBook/parportbook.tmpl
index bf4d77873..754f1a96b 100644
--- a/Documentation/DocBook/parportbook.tmpl
+++ b/Documentation/DocBook/parportbook.tmpl
@@ -24,30 +24,12 @@
 
   <legalnotice>
    <para>
-     This documentation is free software; you can redistribute
-     it and/or modify it under the terms of the GNU General Public
-     License as published by the Free Software Foundation; either
-     version 2 of the License, or (at your option) any later
-     version.
-   </para>
-      
-   <para>
-     This program is distributed in the hope that it will be
-     useful, but WITHOUT ANY WARRANTY; without even the implied
-     warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
-     See the GNU General Public License for more details.
-   </para>
-      
-   <para>
-     You should have received a copy of the GNU General Public
-     License along with this program; if not, write to the Free
-     Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
-     MA 02111-1307 USA
-   </para>
-      
-   <para>
-     For more details see the file COPYING in the source
-     distribution of Linux.
+    Permission is granted to copy, distribute and/or modify this
+    document under the terms of the GNU Free Documentation License,
+    Version 1.1 or any later version published by the Free Software
+    Foundation; with no Invariant Sections, with no Front-Cover Texts,
+    and with no Back-Cover Texts.  A copy of the license is included
+    in the section entitled "GNU Free Documentation License".
    </para>
   </legalnotice>
  </bookinfo>
@@ -2209,9 +2191,9 @@ ssize_t write_printer (int fd, const void *ptr, size_t count)
 
  </chapter>
 
- <appendix>
+ <appendix id="api">
   <title>
-   API reference
+   Linux parallel port driver API reference
   </title>
 
 !Fdrivers/parport/daisy.c parport_device_num
@@ -2314,10 +2296,375 @@ ssize_t write_printer (int fd, const void *ptr, size_t count)
    removed.
   </para>
  </appendix>
+
+ <appendix id="fdl">
+  <title>
+   GNU Free Documentation License
+  </title>
+
+  <literallayout class="monospaced">
+                GNU Free Documentation License
+                   Version 1.1, March 2000
+
+ Copyright (C) 2000  Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+0. PREAMBLE
+
+The purpose of this License is to make a manual, textbook, or other
+written document "free" in the sense of freedom: to assure everyone
+the effective freedom to copy and redistribute it, with or without
+modifying it, either commercially or noncommercially.  Secondarily,
+this License preserves for the author and publisher a way to get
+credit for their work, while not being considered responsible for
+modifications made by others.
+
+This License is a kind of "copyleft", which means that derivative
+works of the document must themselves be free in the same sense.  It
+complements the GNU General Public License, which is a copyleft
+license designed for free software.
+
+We have designed this License in order to use it for manuals for free
+software, because free software needs free documentation: a free
+program should come with manuals providing the same freedoms that the
+software does.  But this License is not limited to software manuals;
+it can be used for any textual work, regardless of subject matter or
+whether it is published as a printed book.  We recommend this License
+principally for works whose purpose is instruction or reference.
+
+
+1. APPLICABILITY AND DEFINITIONS
+
+This License applies to any manual or other work that contains a
+notice placed by the copyright holder saying it can be distributed
+under the terms of this License.  The "Document", below, refers to any
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+A "Modified Version" of the Document means any work containing the
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+The "Invariant Sections" are certain Secondary Sections whose titles
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+The "Cover Texts" are certain short passages of text that are listed,
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+2. VERBATIM COPYING
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+
+6. COLLECTIONS OF DOCUMENTS
+
+You may make a collection consisting of the Document and other documents
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+
+You may extract a single document from such a collection, and distribute
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+License into the extracted document, and follow this License in all
+other respects regarding verbatim copying of that document.
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+
+
+7. AGGREGATION WITH INDEPENDENT WORKS
+
+A compilation of the Document or its derivatives with other separate
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+distribution medium, does not as a whole count as a Modified Version
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+compilation.  Such a compilation is called an "aggregate", and this
+License does not apply to the other self-contained works thus compiled
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+are not themselves derivative works of the Document.
+
+If the Cover Text requirement of section 3 is applicable to these
+copies of the Document, then if the Document is less than one quarter
+of the entire aggregate, the Document's Cover Texts may be placed on
+covers that surround only the Document within the aggregate.
+Otherwise they must appear on covers around the whole aggregate.
+
+
+8. TRANSLATION
+
+Translation is considered a kind of modification, so you may
+distribute translations of the Document under the terms of section 4.
+Replacing Invariant Sections with translations requires special
+permission from their copyright holders, but you may include
+translations of some or all Invariant Sections in addition to the
+original versions of these Invariant Sections.  You may include a
+translation of this License provided that you also include the
+original English version of this License.  In case of a disagreement
+between the translation and the original English version of this
+License, the original English version will prevail.
+
+
+9. TERMINATION
+
+You may not copy, modify, sublicense, or distribute the Document except
+as expressly provided for under this License.  Any other attempt to
+copy, modify, sublicense or distribute the Document is void, and will
+automatically terminate your rights under this License.  However,
+parties who have received copies, or rights, from you under this
+License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+
+10. FUTURE REVISIONS OF THIS LICENSE
+
+The Free Software Foundation may publish new, revised versions
+of the GNU Free Documentation License from time to time.  Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns. See
+http:///www.gnu.org/copyleft/.
+
+Each version of the License is given a distinguishing version number.
+If the Document specifies that a particular numbered version of this
+License "or any later version" applies to it, you have the option of
+following the terms and conditions either of that specified version or
+of any later version that has been published (not as a draft) by the
+Free Software Foundation.  If the Document does not specify a version
+number of this License, you may choose any version ever published (not
+as a draft) by the Free Software Foundation.
+
+
+ADDENDUM: How to use this License for your documents
+
+To use this License in a document you have written, include a copy of
+the License in the document and put the following copyright and
+license notices just after the title page:
+
+      Copyright (c)  YEAR  YOUR NAME.
+      Permission is granted to copy, distribute and/or modify this document
+      under the terms of the GNU Free Documentation License, Version 1.1
+      or any later version published by the Free Software Foundation;
+      with the Invariant Sections being LIST THEIR TITLES, with the
+      Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
+      A copy of the license is included in the section entitled "GNU
+      Free Documentation License".
+
+If you have no Invariant Sections, write "with no Invariant Sections"
+instead of saying which ones are invariant.  If you have no
+Front-Cover Texts, write "no Front-Cover Texts" instead of
+"Front-Cover Texts being LIST"; likewise for Back-Cover Texts.
+
+If your document contains nontrivial examples of program code, we
+recommend releasing these examples in parallel under your choice of
+free software license, such as the GNU General Public License,
+to permit their use in free software.
+  </literallayout>
+ </appendix>
+
 </book>
 
 <!-- Local Variables: -->
 <!-- sgml-indent-step: 1 -->
 <!-- sgml-indent-data: 1 -->
 <!-- End: -->
-
diff --git a/Documentation/fb/framebuffer.txt b/Documentation/fb/framebuffer.txt
index e8c51d1b5..94da7175d 100644
--- a/Documentation/fb/framebuffer.txt
+++ b/Documentation/fb/framebuffer.txt
@@ -332,7 +332,7 @@ and on its mirrors.
 
 The latest version of fbset can be found at
 
-    http://www.cs.kuleuven.ac.be/~geert/bin/
+    http://home.tvd.be/cr26864/Linux/fbdev/
 
   
 10. Credits                                                       
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
new file mode 100644
index 000000000..0dd2cc8eb
--- /dev/null
+++ b/Documentation/filesystems/Locking
@@ -0,0 +1,315 @@
+	The text below describes the locking rules for VFS-related methods.
+It is (believed to be) up-to-date. *Please*, if you change anything in
+prototypes or locking protocols - update this file. And update the relevant
+instances in the tree, don't leave that to maintainers of filesystems/devices/
+etc. At the very least, put the list of dubious cases in the end of this file.
+Don't turn it into log - maintainers of out-of-the-tree code are supposed to
+be able to use diff(1).
+	Thing currently missing here: socket operations. Alexey?
+
+--------------------------- dentry_operations --------------------------
+prototypes:
+	int (*d_revalidate)(struct dentry *, int);
+	int (*d_hash) (struct dentry *, struct qstr *);
+	int (*d_compare) (struct dentry *, struct qstr *, struct qstr *);
+	int (*d_delete)(struct dentry *);
+	void (*d_release)(struct dentry *);
+	void (*d_iput)(struct dentry *, struct inode *);
+
+locking rules:
+	none have BKL
+		dcache_lock	may block
+d_revalidate:	no		yes
+d_hash		no		yes
+d_compare:	yes		no
+d_delete:	yes		no
+d_release:	no		yes
+d_iput:		no		yes
+
+--------------------------- inode_operations --------------------------- 
+prototypes:
+	int (*create) (struct inode *,struct dentry *,int);
+	struct dentry * (*lookup) (struct inode *,struct dentry *);
+	int (*link) (struct dentry *,struct inode *,struct dentry *);
+	int (*unlink) (struct inode *,struct dentry *);
+	int (*symlink) (struct inode *,struct dentry *,const char *);
+	int (*mkdir) (struct inode *,struct dentry *,int);
+	int (*rmdir) (struct inode *,struct dentry *);
+	int (*mknod) (struct inode *,struct dentry *,int,int);
+	int (*rename) (struct inode *, struct dentry *,
+			struct inode *, struct dentry *);
+	int (*readlink) (struct dentry *, char *,int);
+	int (*follow_link) (struct dentry *, struct nameidata *);
+	void (*truncate) (struct inode *);
+	int (*permission) (struct inode *, int);
+	int (*revalidate) (struct dentry *);
+	int (*setattr) (struct dentry *, struct iattr *);
+	int (*getattr) (struct dentry *, struct iattr *);
+
+locking rules:
+	all may block
+		BKL	i_sem(inode)	i_zombie(inode)
+lookup:		yes	yes		no
+create:		yes	yes		yes
+link:		yes	yes		yes
+mknod:		yes	yes		yes
+mkdir:		yes	yes		yes
+unlink:		yes	yes		yes
+rmdir:		yes	yes		yes		(see below)
+rename:		yes	yes (both)	yes (both)	(see below)
+readlink:	no	no		no
+follow_link:	no	no		no
+truncate:	yes	yes		no		(see below)
+setattr:	yes	if ATTR_SIZE	no
+permssion:	yes	no		no
+getattr:						(see below)
+revalidate:	no					(see below)
+	Additionally, ->rmdir() has i_zombie on victim and so does ->rename()
+in case when target exists and is a directory.
+	->revalidate(), it may be called both with and without the i_sem
+on dentry->d_inode. VFS never calls it with i_zombie on dentry->d_inode,
+but watch for other methods directly calling this one...
+	->truncate() is never called directly - it's a callback, not a
+method. It's called by vmtruncate() - library function normally used by
+->setattr(). Locking information above applies to that call (i.e. is
+inherited from ->setattr() - vmtruncate() is used when ATTR_SIZE had been
+passed).
+	->getattr() is currently unused.
+
+--------------------------- super_operations ---------------------------
+prototypes:
+	void (*read_inode) (struct inode *);
+	void (*write_inode) (struct inode *, int);
+	void (*put_inode) (struct inode *);
+	void (*delete_inode) (struct inode *);
+	void (*put_super) (struct super_block *);
+	void (*write_super) (struct super_block *);
+	int (*statfs) (struct super_block *, struct statfs *);
+	int (*remount_fs) (struct super_block *, int *, char *);
+	void (*clear_inode) (struct inode *);
+	void (*umount_begin) (struct super_block *);
+
+locking rules:
+	All may block.
+		BKL	s_lock	mount_sem
+read_inode:	yes				(see below)
+write_inode:	no	
+put_inode:	no	
+delete_inode:	no	
+clear_inode:	no	
+put_super:	yes	yes	maybe		(see below)
+write_super:	yes	yes	maybe		(see below)
+statfs:		yes	no	no
+remount_fs:	yes	yes	maybe		(see below)
+umount_begin:	yes	no	maybe		(see below)
+
+->read_inode() is not a method - it's a callback used in iget()/iget4().
+rules for mount_sem are not too nice - it is going to die and be replaced
+by better scheme anyway.
+
+--------------------------- file_system_type ---------------------------
+prototypes:
+	struct super_block *(*read_super) (struct super_block *, void *, int);
+locking rules:
+may block	BKL	->s_lock	mount_sem
+yes		yes	yes		maybe
+
+--------------------------- address_space_operations --------------------------
+prototypes:
+	int (*writepage)(struct file *, struct page *);
+	int (*readpage)(struct file *, struct page *);
+	int (*sync_page)(struct page *);
+	int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
+	int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
+	int (*bmap)(struct address_space *, long);
+locking rules:
+	All may block
+		BKL	PageLocked(page)
+writepage:	no	yes
+readpage:	no	yes
+sync_page:	no	maybe
+prepare_write:	no	yes
+commit_write:	no	yes
+bmap:		yes
+
+	->prepare_write(), ->commit_write(), ->sync_page() and ->readpage()
+may be called from the request handler (/dev/loop).
+	->sync_page() locking rules are not well-defined - usually it is called
+with lock on page, but that is not guaranteed. Considering the currently
+existsing instances of this method ->sync_page() itself doesn't look
+well-defined...
+	->bmap() is currently used by legacy ioctl() (FIBMAP) provided by some
+filesystems and by the swapper. The latter will eventually go away. All
+instances do not actually need the BKL. Please, keep it that way and don't
+breed new callers.
+	Note: currently almost all instances of address_space methods are
+using BKL for internal serialization and that's one of the worst sources
+of contention. Normally they are calling library functions (in fs/buffer.c)
+and pass foo_get_block() as a callback (on local block-based filesystems,
+indeed). BKL is not needed for library stuff and is usually taken by
+foo_get_block(). It's an overkill, since block bitmaps can be protected by
+internal fs locking and real critical areas are much smaller than the areas
+filesystems protect now.
+
+--------------------------- file_lock ------------------------------------
+prototypes:
+	void (*fl_notify)(struct file_lock *);	/* unblock callback */
+	void (*fl_insert)(struct file_lock *);	/* lock insertion callback */
+	void (*fl_remove)(struct file_lock *);	/* lock removal callback */
+
+locking rules:
+		BKL	may block
+fl_notify:	yes	no
+fl_insert:	yes	maybe
+fl_remove:	yes	maybe
+	Currently only NLM provides instances of this class. None of the
+them block. If you have out-of-tree instances - please, show up. Locking
+in that area will change.
+
+--------------------------- buffer_head -----------------------------------
+prototypes:
+	void (*b_end_io)(struct buffer_head *bh, int uptodate);
+
+locking rules:
+	called from interrupts. In other words, extreme care is needed here.
+bh is locked, but that's all warranties we have here. Currently only RAID1,
+highmem and fs/buffer.c are providing these. Block devices call this method
+upon the IO completion.
+
+--------------------------- block_device_operations -----------------------
+prototypes:
+	int (*open) (struct inode *, struct file *);
+	int (*release) (struct inode *, struct file *);
+	int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
+	int (*check_media_change) (kdev_t);
+	int (*revalidate) (kdev_t);
+locking rules:
+			BKL	bd_sem
+open:			yes	yes
+release:		yes	yes
+ioctl:			yes	no
+check_media_change:	yes	no
+revalidate:		yes	no
+
+The last two are called only from check_disk_change(). Prototypes are very
+bad - as soon as we'll get disk_struct they will change (and methods will
+become per-disk instead of per-partition).
+
+--------------------------- file_operations -------------------------------
+prototypes:
+	loff_t (*llseek) (struct file *, loff_t, int);
+	ssize_t (*read) (struct file *, char *, size_t, loff_t *);
+	ssize_t (*write) (struct file *, const char *, size_t, loff_t *);
+	int (*readdir) (struct file *, void *, filldir_t);
+	unsigned int (*poll) (struct file *, struct poll_table_struct *);
+	int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
+	int (*mmap) (struct file *, struct vm_area_struct *);
+	int (*open) (struct inode *, struct file *);
+	int (*flush) (struct file *);
+	int (*release) (struct inode *, struct file *);
+	int (*fsync) (struct file *, struct dentry *, int datasync);
+	int (*fasync) (int, struct file *, int);
+	int (*lock) (struct file *, int, struct file_lock *);
+	ssize_t (*readv) (struct file *, const struct iovec *, unsigned long, loff_t *);
+	ssize_t (*writev) (struct file *, const struct iovec *, unsigned long, loff_t *);
+};
+
+locking rules:
+	All except ->poll() may block.
+		BKL
+llseek:		yes
+read:		no
+write:		no
+readdir:	yes	(see below)
+poll:		no
+ioctl:		yes	(see below)
+mmap:		no
+open:		maybe	(see below)
+flush:		yes
+release:	yes
+fsync:		yes	(see below)
+fasync:		yes	(see below)
+lock:		yes
+readv:		no
+writev:		no
+
+->open() locking is in-transit: big lock partially moved into the methods.
+The only exception is ->open() in the instances of file_operations that never
+end up in ->i_fop/->proc_fops, i.e. ones that belong to character devices
+(chrdev_open() takes lock before replacing ->f_op and calling the secondary
+method. As soon as we fix the handling of module reference counters all
+instances of ->open() will be called without the BKL. At the same point
+->release() will lose BKL. Currently ext2_release() is *the* source of
+contention on fs-intensive loads and dropping BKL on ->release() will get
+rid of that (we will still need some locking for cases when we close a file
+that had been opened r/w, but that can be done using the internal locking with
+smaller critical areas). sock_close() is also going to win from that change.
+
+->fasync() is a mess. This area needs a big cleanup and that will probably
+affect locking.
+
+->readdir() and ->ioctl() on directories must be changed. Ideally we would
+move ->readdir() to inode_operations and use a separate method for directory
+->ioctl() or kill the latter completely. One of the problems is that for
+anything that resembles union-mount we won't have a struct file for all
+components. And there are other reasons why the current interface is a mess...
+
+->read on directories probably must go away - we should just enforce -EISDIR
+in sys_read() and friends.
+
+->fsync() has i_sem on inode.
+
+--------------------------- dquot_operations -------------------------------
+prototypes:
+	void (*initialize) (struct inode *, short);
+	void (*drop) (struct inode *);
+	int (*alloc_block) (const struct inode *, unsigned long, char);
+	int (*alloc_inode) (const struct inode *, unsigned long);
+	void (*free_block) (const struct inode *, unsigned long);
+	void (*free_inode) (const struct inode *, unsigned long);
+	int (*transfer) (struct dentry *, struct iattr *);
+
+locking rules:
+		BKL
+initialize:	no
+drop:		no
+alloc_block:	yes
+alloc_inode:	yes
+free_block:	yes
+free_inode:	yes
+transfer:	no
+
+--------------------------- vm_operations_struct -----------------------------
+prototypes:
+	void (*open)(struct vm_area_struct*);
+	void (*close)(struct vm_area_struct*);
+	void (*unmap)(struct vm_area_struct*, unsigned long, size_t);
+	void (*protect)(struct vm_area_struct*, unsigned long, size_t, unsigned);
+	int (*sync)(struct vm_area_struct*, unsigned long, size_t, unsigned);
+	struct page *(*nopage)(struct vm_area_struct*, unsigned long, int);
+	struct page *(*wppage)(struct vm_area_struct*, unsigned long, struct page*);
+	int (*swapout)(struct page *, struct file *);
+
+locking rules:
+		BKL	mmap_sem
+open:		no	yes
+close:		no	yes
+sync:		no	yes
+unmap:		no	yes
+nopage:		no	yes
+swapout:	yes	yes
+wpppage:				(see below)
+protect:				(see below)
+
+->wppage() and ->protect() have no instances and nothing calls them; looks like
+they must die...
+
+================================================================================
+			Dubious stuff
+
+(if you break something or notice that it is broken and do not fix it yourself
+- at least put it here)
+
+ipc/shm.c::shm_delete() - may need BKL.
+->read() and ->write() in many drivers are (probably) missing BKL.
+drivers/sgi/char/graphics.c::sgi_graphics_nopage() - may need BKL.