coda: pass the host file in vma->vm_file on mmap
authorJan Harkes <jaharkes@cs.cmu.edu>
Tue, 16 Jul 2019 23:28:04 +0000 (16:28 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 17 Jul 2019 02:23:22 +0000 (19:23 -0700)
commit7fa0a1da3dadfd9216df7745a1331fdaa0940d1c
tree78dac0029793a8831f7bff1df20a795efd020c16
parentb98cca444d287a63dd96df04af7fb9793567599e
coda: pass the host file in vma->vm_file on mmap

Patch series "Coda updates".

The following patch series is a collection of various fixes for Coda,
most of which were collected from linux-fsdevel or linux-kernel but
which have as yet not found their way upstream.

This patch (of 22):

Various file systems expect that vma->vm_file points at their own file
handle, several use file_inode(vma->vm_file) to get at their inode or
use vma->vm_file->private_data.  However the way Coda wrapped mmap on a
host file broke this assumption, vm_file was still pointing at the Coda
file and the host file systems would scribble over Coda's inode and
private file data.

This patch fixes the incorrect expectation and wraps vm_ops->open and
vm_ops->close to allow Coda to track when the vm_area_struct is
destroyed so we still release the reference on the Coda file handle at
the right time.

Link: http://lkml.kernel.org/r/0e850c6e59c0b147dc2dcd51a3af004c948c3697.1558117389.git.jaharkes@cs.cmu.edu
Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Mikko Rapeli <mikko.rapeli@iki.fi>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Yann Droneaud <ydroneaud@opteya.com>
Cc: Zhouyang Jia <jiazhouyang09@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/coda/file.c