- Add cache=mmap option
 - Make mmap read-write while keeping it as synchronous as possible
 - Build writeback fid on mmap creation if it is writable
Signed-off-by: NDominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Some of the flags are OS/arch dependent we add a 9p
protocol value which maps to asm-generic/fcntl.h values in Linux
Based on the original patch from Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

We should only update attributes that we can change on stat2inode.
Also do file type initialization in v9fs_init_inode.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Btrfs needs to be able to control how filemap_write_and_wait_range() is called
in fsync to make it less of a painful operation, so push down taking i_mutex and
the calling of filemap_write_and_wait() down into the ->fsync() handlers.  Some
file systems can drop taking the i_mutex altogether it seems, like ext3 and
ocfs2.  For correctness sake I just pushed everything down in all cases to make
sure that we keep the current behavior the same for everybody, and then each
individual fs maintainer can make up their mind about what to do from there.
Thanks,
Acked-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJosef Bacik <josef@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Add necessary #ifndef #endif blocks to avoid mulitple inclusion of same headers
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

With cached mode some of the file system operation result
in updating inode attributes (ctime). Add support for
marking inode attribute invalid in such cases so that
we fetch the updated inode attribute on dentry revalidation.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Switch to the fscache code to v9fs_inode. We will later use
v9fs_inode in cache=loose mode to track the inode cache
validity timeout. Ie if we find an inode in cache older
that a specific jiffie range we will consider it stale
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

We didn't add the inode to inode hash in 9p. We need to do that
to get sync to work, otherwise __mark_inode_dirty will not
add the inode to super block's dirty list.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

We add read write helper function here which will
be used later by the mmap patch
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

With the old code we were not setting the file->f_op
with cached file operations during creat.

(format correction by jvrao@linux.vnet.ibm.com)
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

here we actually *want* ->d_op for root; setting it allows to get rid
of kludge in v9fs_kill_super() since now we have proper ->d_release()
for root and don't need to call it manually.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

SYNOPSIS
    size[4] Tfsync tag[2] fid[4] datasync[4]

    size[4] Rfsync tag[2]

DESCRIPTION

    The Tfsync transaction transfers ("flushes") all modified in-core data of
    file identified by fid to the disk device (or other  permanent  storage
    device)  where that  file  resides.

    If datasync flag is specified data will be fleshed but does not flush
    modified metadata unless  that  metadata  is  needed  in order to allow a
    subsequent data retrieval to be correctly handled.
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Synopsis

    size[4] TLock tag[2] fid[4] flock[n]
    size[4] RLock tag[2] status[1]

Description

Tlock is used to acquire/release byte range posix locks on a file
identified by given fid. The reply contains status of the lock request

    flock structure:
        type[1] - Type of lock: F_RDLCK, F_WRLCK, F_UNLCK
        flags[4] - Flags could be either of
          P9_LOCK_FLAGS_BLOCK - Blocked lock request, if there is a
            conflicting lock exists, wait for that lock to be released.
          P9_LOCK_FLAGS_RECLAIM - Reclaim lock request, used when client is
            trying to reclaim a lock after a server restrart (due to crash)
        start[8] - Starting offset for lock
        length[8] - Number of bytes to lock
          If length is 0, lock all bytes starting at the location 'start'
          through to the end of file
        pid[4] - PID of the process that wants to take lock
        client_id[4] - Unique client id

        status[1] - Status of the lock request, can be
          P9_LOCK_SUCCESS(0), P9_LOCK_BLOCKED(1), P9_LOCK_ERROR(2) or
          P9_LOCK_GRACE(3)
          P9_LOCK_SUCCESS - Request was successful
          P9_LOCK_BLOCKED - A conflicting lock is held by another process
          P9_LOCK_ERROR - Error while processing the lock request
          P9_LOCK_GRACE - Server is in grace period, it can't accept new lock
            requests in this period (except locks with
            P9_LOCK_FLAGS_RECLAIM flag set)
Signed-off-by: NM. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

This patch also update mode bits, as a normal file system.
I am not sure wether we should do that, considering that
a setxattr on the server will again update the ACL/mode value
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

        SYNOPSIS

              size[4] Tgetattr tag[2] fid[4] request_mask[8]

              size[4] Rgetattr tag[2] lstat[n]

           DESCRIPTION

              The getattr transaction inquires about the file identified by fid.
              request_mask is a bit mask that specifies which fields of the
              stat structure is the client interested in.

              The reply will contain a machine-independent directory entry,
              laid out as follows:

                 st_result_mask[8]
                    Bit mask that indicates which fields in the stat structure
                    have been populated by the server

                 qid.type[1]
                    the type of the file (directory, etc.), represented as a bit
                    vector corresponding to the high 8 bits of the file's mode
                    word.

                 qid.vers[4]
                    version number for given path

                 qid.path[8]
                    the file server's unique identification for the file

                 st_mode[4]
                    Permission and flags

                 st_uid[4]
                    User id of owner

                 st_gid[4]
                    Group ID of owner

                 st_nlink[8]
                    Number of hard links

                 st_rdev[8]
                    Device ID (if special file)

                 st_size[8]
                    Size, in bytes

                 st_blksize[8]
                    Block size for file system IO

                 st_blocks[8]
                    Number of file system blocks allocated

                 st_atime_sec[8]
                    Time of last access, seconds

                 st_atime_nsec[8]
                    Time of last access, nanoseconds

                 st_mtime_sec[8]
                    Time of last modification, seconds

                 st_mtime_nsec[8]
                    Time of last modification, nanoseconds

                 st_ctime_sec[8]
                    Time of last status change, seconds

                 st_ctime_nsec[8]
                    Time of last status change, nanoseconds

                 st_btime_sec[8]
                    Time of creation (birth) of file, seconds

                 st_btime_nsec[8]
                    Time of creation (birth) of file, nanoseconds

                 st_gen[8]
                    Inode generation

                 st_data_version[8]
                    Data version number

              request_mask and result_mask bit masks contain the following bits
                 #define P9_STATS_MODE          0x00000001ULL
                 #define P9_STATS_NLINK         0x00000002ULL
                 #define P9_STATS_UID           0x00000004ULL
                 #define P9_STATS_GID           0x00000008ULL
                 #define P9_STATS_RDEV          0x00000010ULL
                 #define P9_STATS_ATIME         0x00000020ULL
                 #define P9_STATS_MTIME         0x00000040ULL
                 #define P9_STATS_CTIME         0x00000080ULL
                 #define P9_STATS_INO           0x00000100ULL
                 #define P9_STATS_SIZE          0x00000200ULL
                 #define P9_STATS_BLOCKS        0x00000400ULL

                 #define P9_STATS_BTIME         0x00000800ULL
                 #define P9_STATS_GEN           0x00001000ULL
                 #define P9_STATS_DATA_VERSION  0x00002000ULL

                 #define P9_STATS_BASIC         0x000007ffULL
                 #define P9_STATS_ALL           0x00003fffULL

        This patch implements the client side of getattr implementation for
        9P2000.L. It introduces a new structure p9_stat_dotl for getting
        Linux stat information along with QID. The data layout is similar to
        stat structure in Linux user space with the following major
        differences:

        inode (st_ino) is not part of data. Instead qid is.

        device (st_dev) is not part of data because this doesn't make sense
        on the client.

        All time variables are 64 bit wide on the wire. The kernel seems to use
        32 bit variables for these variables. However, some of the architectures
        have used 64 bit variables and glibc exposes 64 bit variables to user
        space on some architectures. Hence to be on the safer side we have made
        these 64 bit in the protocol. Refer to the comments in
        include/asm-generic/stat.h

        There are some additional fields: st_btime_sec, st_btime_nsec, st_gen,
        st_data_version apart from the bitmask, st_result_mask. The bit mask
        is filled by the server to indicate which stat fields have been
        populated by the server. Currently there is no clean way for the
        server to obtain these additional fields, so it sends back just the
        basic fields.
Signed-off-by: NSripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: NEric Van Hensbegren <ericvh@gmail.com>

Implements VFS switches for 9p2000.L protocol.
Signed-off-by: NSripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Implement the fsync in the client side by marking stat field values to 'don't touch' so that server may 
interpret it as a request to guarantee that the contents of the associated file are committed to stable 
storage before the Rwstat message is returned.

Without this patch, calling fsync on a 9p file results in "Invalid argument" error. Please check the attached 
C program.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> 
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com> 
Acked-by: NVenkateswararao Jujjuri (JV) <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

This patch adds a persistent, read-only caching facility for
9p clients using the FS-Cache caching backend.

When the fscache facility is enabled, each inode is associated
with a corresponding vcookie which is an index into the FS-Cache
indexing tree. The FS-Cache indexing tree is indexed at 3 levels:
- session object associated with each mount.
- inode/vcookie
- actual data (pages)

A cache tag is chosen randomly for each session. These tags can
be read off /sys/fs/9p/caches and can be passed as a mount-time
parameter to re-attach to the specified caching session.
Signed-off-by: NAbhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Now that the new protocol functions are in place, this patch switches
the client code to using the new support code.
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

There are a couple of methods in the client code which aren't actually
wire operations.  To keep things organized cleaner, these operations are
being moved to the fs layer.

This patch moves the readn meta-function (which executes multiple wire
reads until a buffer is full) to the fs layer.
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

The legacy protocol's open operation doesn't handle an append operation
(it is expected that the client take care of it).  We were incorrectly
passing the extended protocol's flag through even in legacy mode.  This
was reported in bugzilla report #10689.  This patch fixes the problem
by disallowing extended protocol open modes from being passed in legacy
mode and implemented append functionality on the client side by adding
a seek after the open.
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

This patchset moves non-filesystem interfaces of v9fs from fs/9p to net/9p.
It moves the transport, packet marshalling and connection layers to net/9p
leaving only the VFS related files in fs/9p.  This work is being done in
preparation for in-kernel 9p servers as well as alternate 9p clients (other
than VFS).
Signed-off-by: NLatchesar Ionkov <lucho@ionkov.net>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

This patch makes te needlessly global struct v9fs_cached_file_operations
static.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

While cacheing is generally frowned upon in the 9p world, it has its
place -- particularly in situations where the remote file system is
exclusive and/or read-only.  The vacfs views of venti content addressable
store are a real-world instance of such a situation.  To facilitate higher
performance for these workloads (and eventually use the fscache patches),
we have enabled a "loose" cache mode which does not attempt to maintain
any form of consistency on the page-cache or dcache.  This results in over
two orders of magnitude performance improvement for cacheable block reads
in the Bonnie benchmark.  The more aggressive use of the dcache also seems
to improve metadata operational performance.
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Same as with already do with the file operations: keep them in .rodata and
prevents people from doing runtime patching.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This is a conversion to make the various file_operations structs in fs/
const.  Basically a regexp job, with a few manual fixups

The goal is both to increase correctness (harder to accidentally write to
shared datastructures) and reducing the false sharing of cachelines with
things that get dirty in .data (while .rodata is nicely read only and thus
cache clean)
Signed-off-by: NArjan van de Ven <arjan@infradead.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Update license boilerplate to specify GPLv2 and remove the (at your option
clause).  This change was agreed to by all the copyright holders (approvals
can be found on v9fs-developer mailing list).
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

In order to assure atomic create+open v9fs stores the open fid produced by
v9fs_vfs_create in the dentry, from where v9fs_file_open retrieves it and
associates it with the open file.

This patch modifies v9fs to use nameidata.intent.open values to do the atomic
create+open.
Signed-off-by: NLatchesar Ionkov <lucho@ionkov.net>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

v9fs mmap support was originally removed from v9fs at Al Viro's request,
but recently there have been requests from folks who want readpage
functionality (primarily to enable execution of files mounted via 9P).
This patch adds readpage support (but not writepage which contained most of
the objectionable code).  It passes fsx-linux (and other regressions) so it
should be relatively safe.
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Performance enhancement reducing the number of copies in the data and
stat paths.
Signed-off-by: NLatchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This part of the patch contains VFS superblock and mapping code.
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>