linux-toradex.git/fs/cifs/file.c, branch v3.0.77

cifs: fix oops while traversing open file list (try #4)

2012-06-09T15:32:58+00:00

commit 2c0c2a08bed7a3b791f88d09d16ace56acb3dd98 upstream.

While traversing the linked list of open file handles, if the identfied
file handle is invalid, a reopen is attempted and if it fails, we
resume traversing where we stopped and cifs can oops while accessing
invalid next element, for list might have changed.

So mark the invalid file handle and attempt reopen if no
valid file handle is found in rest of the list.
If reopen fails, move the invalid file handle to the end of the list
and start traversing the list again from the begining.
Repeat this four times before giving up and returning an error if
file reopen keeps failing.

Signed-off-by: Shirish Pargaonkar 
Reviewed-by: Jeff Layton 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

CIFS: Fix wrong length in cifs_iovec_read

2011-07-21T00:48:05+00:00

Signed-off-by: Pavel Shilovsky 
Reviewed-by: Jeff Layton 
Signed-off-by: Steve French

[CIFS] Rename three structures to avoid camel case

2011-05-27T04:34:02+00:00

secMode to sec_mode
and
cifsTconInfo to cifs_tcon
and
cifsSesInfo to cifs_ses

Signed-off-by: Steve French

CIFS: Add rwpidforward mount option

2011-05-27T03:57:16+00:00

Add rwpidforward mount option that switches on a mode when we forward
pid of a process who opened a file to any read and write operation.

This can prevent applications like WINE from failing on read or write
operation on a previously locked file region from the same netfd from
another process if we use mandatory brlock style.

It is actual for WINE because during a run of WINE program two processes
work on the same netfd - share the same file struct between several VFS
fds:
1) WINE-server does open and lock;
2) WINE-application does read and write.

Signed-off-by: Pavel Shilovsky 
Signed-off-by: Steve French

CIFS: Use pid saved from cifsFileInfo in writepages and set_file_size

2011-05-26T18:07:02+00:00

We need it to make them work with mandatory locking style because
we can fail in a situation like when kernel need to flush dirty pages
and there is a lock held by a process who opened file.

Signed-off-by: Pavel Shilovsky 
Signed-off-by: Steve French

cifs: convert cifs_writepages to use async writes

2011-05-25T20:05:03+00:00

Have cifs_writepages issue asynchronous writes instead of waiting on
each write call to complete before issuing another. This also allows us
to return more quickly from writepages. It can just send out all of the
I/Os and not wait around for the replies.

In the WB_SYNC_ALL case, if the write completes with a retryable error,
then the completion workqueue job will resend the write.

This also changes the page locking semantics a little bit. Instead of
holding the page lock until the response is received, release it after
doing the send. This will reduce contention for the page lock and should
prevent processes that have the file mmap'ed from being blocked
unnecessarily.

Signed-off-by: Jeff Layton 
Reviewed-and-Tested-by: Pavel Shilovsky 
Signed-off-by: Steve French

CIFS: Simplify invalidate part (try #5)

2011-05-19T14:10:52+00:00

Simplify many places when we call cifs_revalidate/invalidate to make
it do what it exactly needs.

Reviewed-by: Jeff Layton 
Signed-off-by: Pavel Shilovsky 
Signed-off-by: Steve French

CIFS: directio read/write cleanups

2011-05-19T14:10:51+00:00

Recently introduced strictcache mode brought a new code that can be
efficiently used by directio part. That's let us add vectored operations
and break unnecessary cifs_user_read and cifs_user_write.

Signed-off-by: Pavel Shilovsky 
Reviewed-by: Jeff Layton 
Signed-off-by: Steve French

CIFS: Add launder_page operation (try #3)

2011-05-19T14:10:50+00:00

Add this let us drop filemap_write_and_wait from cifs_invalidate_mapping
and simplify the code to properly process invalidate logic.

Reviewed-by: Jeff Layton 
Signed-off-by: Pavel Shilovsky 
Signed-off-by: Steve French

cifs: don't allow mmap'ed pages to be dirtied while under writeback (try #3)

2011-04-12T14:19:55+00:00

This is more or less the same patch as before, but with some merge
conflicts fixed up.

If a process has a dirty page mapped into its page tables, then it has
the ability to change it while the client is trying to write the data
out to the server. If that happens after the signature has been
calculated then that signature will then be wrong, and the server will
likely reset the TCP connection.

This patch adds a page_mkwrite handler for CIFS that simply takes the
page lock. Because the page lock is held over the life of writepage and
writepages, this prevents the page from becoming writeable until
the write call has completed.

With this, we can also remove the "sign_zero_copy" module option and
always inline the pages when writing.

Signed-off-by: Jeff Layton 
Signed-off-by: Steve French