This patch implement fetching POSIX ACL from the server
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>

The ACL value is fetched as a part of inode initialization
from the server and the permission checking function use the
cached value of the ACL
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>

the same calculation is done in p9_client_write
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NBadari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

The presence of v9fs_direct_IO() in the address space ops vector
allowes open() O_DIRECT flags which would have failed otherwise.

In the non-cached mode, we shunt off direct read and write requests before
the VFS gets them, so this method should never be called.

Direct IO is not 'yet' supported in the cached mode. Hence when
this routine is called through generic_file_aio_read(), the read/write fails
with an error.
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

The current implementation of 9p client mkdir function does not
set the S_ISGID mode bit for the directory being created if the
parent directory has this bit set. This patch fixes this problem
so that the newly created directory inherits the gid from parent
directory and not from the process creating this directory, when
the S_ISGID bit is set in parent directory.
Signed-off-by: NHarsh Prateek Bora <harsh@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

A patch was accepted recently for sending correct buffer size to p9stat_read.
We need a similar patch in v9fs_dir_readdir_dotl to send correct end of buffer
to p9dirent_read.
Signed-off-by: NSripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Current 9p client file write code does not check for RLIMIT_FSIZE resource.
This bug was found by running LTP test case for setrlimit. This bug is fixed
by calling generic_write_checks before sending the write request to the
server.
Without this patch: the write function is allowed to write above the
RLIMIT_FSIZE set by user.
With this patch: the write function checks for RLIMIT_SIZE and writes upto
the size limit.
Signed-off-by: NHarsh Prateek Bora <harsh@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

git_t is unsigned an can never be less than zero.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Clones an existing reference to inode; caller must already hold one.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We should not use dotlversion for the dotu inode operations
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

We should use the cached dentry operation only if caching mode is enabled
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

NULL fid should be handled in cases where we endup calling v9fs_dir_release()
before even we instantiate the fid in filp.
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

This was introduced by 7cadb63d58a932041afa3f957d5cbb6ce69dcee5
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Four memory leak fixes in the 9P code.
Signed-off-by: NLatchesar Ionkov <lucho@ionkov.net>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

p9_client_walk() can return error values if we run out of space or there
is a problem with the network.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

Replace inode_setattr with opencoded variants of it in all callers.  This
moves the remaining call to vmtruncate into the filesystem methods where it
can be replaced with the proper truncate sequence.

In a few cases it was obvious that we would never end up calling vmtruncate
so it was left out in the opencoded variant:

 spufs: explicitly checks for ATTR_SIZE earlier
 btrfs,hugetlbfs,logfs,dlmfs: explicitly clears ATTR_SIZE earlier
 ufs: contains an opencoded simple_seattr + truncate that sets the filesize just above

In addition to that ncpfs called inode_setattr with handcrafted iattrs,
which allowed to trim down the opencoded variant.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Pass the correct end of the buffer to p9stat_read.
Signed-off-by: NLatchesar Ionkov <lucho@ionkov.net>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

fixes:

  CHECK   fs/9p/xattr.c
	fs/9p/xattr.c:73:6: warning: Using plain integer as NULL pointer
	fs/9p/xattr.c:135:6: warning: Using plain integer as NULL pointer
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

make v9fs_dentry_from_dir_inode static
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

During fid lookup we need to make sure that the dentry->d_parent doesn't
change so that we can safely walk the parent dentries. To ensure that
we need to prevent cross directory rename during fid_lookup. Add a
per superblock rename_sem rw_semaphore to prevent parallel fid lookup and
rename.
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: 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>

Implement 9p2000.L version of open(LOPEN) interface in 9p client.

For LOPEN, no need to convert the flags to and from 9p mode to VFS mode.

Synopsis:

    size[4] Tlopen tag[2] fid[4] mode[4]

    size[4] Rlopen tag[2] qid[13] iounit[4]

[Fix mode bit format - jvrao@linux.vnet.ibm.com]
Signed-off-by: NM. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbegren <ericvh@gmail.com>

SYNOPSIS

    size[4] Tlcreate tag[2] fid[4] name[s] flags[4] mode[4] gid[4]

    size[4] Rlcreate tag[2] qid[13] iounit[4]

DESCRIPTION

The Tlreate request asks the file server to create a new regular file with the
name supplied, in the directory (dir) represented by fid.
The mode argument specifies the permissions to use. New file is created with
the uid if the fid and with supplied gid.

The flags argument represent Linux access mode flags with which the caller
is requesting to open the file with. Protocol allows all the Linux access
modes but it is upto the server to allow/disallow any of these acess modes.
If the server doesn't support any of the access mode, it is expected to
return error.
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Implement TMKDIR as part of 2000.L Work

Synopsis

    size[4] Tmkdir tag[2] fid[4] name[s] mode[4] gid[4]

    size[4] Rmkdir tag[2] qid[13]

Description

    mkdir asks the file server to create a directory with given name,
    mode and gid. The qid for the new directory is returned with
    the mkdir reply message.

Note: 72 is selected as the opcode for TMKDIR from the reserved list.
Signed-off-by: NM. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Synopsis

    size[4] Tmknod tag[2] fid[4] name[s] mode[4] major[4] minor[4] gid[4]

    size[4] Rmknod tag[2] qid[13]

Description

    mknod asks the file server to create a device node with given major and
    minor number, mode and gid. The qid for the new device node is returned
    with the mknod reply message.

[sripathik@in.ibm.com: Fix error handling code]
Signed-off-by: NM. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Create a symbolic link

SYNOPSIS

size[4] Tsymlink tag[2] fid[4] name[s] symtgt[s] gid[4]

size[4] Rsymlink tag[2] qid[13]

DESCRIPTION

Create a symbolic link named 'name' pointing to 'symtgt'.
gid represents the effective group id of the caller.
The  permissions of a symbolic link are irrelevant hence it is omitted
from the protocol.
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Reviewed-by: NSripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

This patch adds a helper function to get the dentry from inode and
uses it in creating a Hardlink

SYNOPSIS

size[4] Tlink tag[2] dfid[4] oldfid[4] newpath[s]

size[4] Rlink tag[2]

DESCRIPTION

Create a link 'newpath' in directory pointed by dfid linking to oldfid path.

[sripathik@in.ibm.com : p9_client_link should not free req structure
if p9_client_rpc has returned an error.]
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

    SYNOPSIS

      size[4] Tsetattr tag[2] attr[n]

      size[4] Rsetattr tag[2]

    DESCRIPTION

      The setattr command changes some of the file status information.
      attr resembles the iattr structure used in Linux kernel. It
      specifies which status parameter is to be changed and to what
      value. It is laid out as follows:

         valid[4]
            specifies which status information is to be changed. Possible
            values are:
            ATTR_MODE       (1 << 0)
            ATTR_UID        (1 << 1)
            ATTR_GID        (1 << 2)
            ATTR_SIZE       (1 << 3)
            ATTR_ATIME      (1 << 4)
            ATTR_MTIME      (1 << 5)
            ATTR_ATIME_SET  (1 << 7)
            ATTR_MTIME_SET  (1 << 8)

            The last two bits represent whether the time information
            is being sent by the client's user space. In the absense
            of these bits the server always uses server's time.

         mode[4]
            File permission bits

         uid[4]
            Owner id of file

         gid[4]
            Group id of the file

         size[8]
            File size

         atime_sec[8]
            Time of last file access, seconds

         atime_nsec[8]
            Time of last file access, nanoseconds

         mtime_sec[8]
            Time of last file modification, seconds

         mtime_nsec[8]
            Time of last file modification, nanoseconds

Explanation of the patches:
--------------------------

*) The kernel just copies relevent contents of iattr structure to
   p9_iattr_dotl structure and passes it down to the client. The
   only check it has is calling inode_change_ok()
*) The p9_iattr_dotl structure does not have ctime and ia_file
   parameters because I don't think these are needed in our case.
   The client user space can request updating just ctime by calling
   chown(fd, -1, -1). This is handled on server side without a need
   for putting ctime on the wire.
*) The server currently supports changing mode, time, ownership and
   size of the file.
*) 9P RFC says "Either all the changes in wstat request happen, or
   none of them does: if the request succeeds, all changes were made;
   if it fails, none were."
   I have not done anything to implement this specifically because I
   don't see a reason.
Signed-off-by: NSripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

        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>

We need to make sure we pass the right uid value
during attach. dotl is similar to dotu in this regard.
Without this mapped security model on dotl doesn't work
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

This patch implements the kernel part of readdir() implementation for 9p2000.L

    Change from V3: Instead of inode, server now sends qids for each dirent

    SYNOPSIS

    size[4] Treaddir tag[2] fid[4] offset[8] count[4]
    size[4] Rreaddir tag[2] count[4] data[count]

    DESCRIPTION

    The readdir request asks the server to read the directory specified by 'fid'
    at an offset specified by 'offset' and return as many dirent structures as
    possible that fit into count bytes. Each dirent structure is laid out as
    follows.

            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

            offset[8]
              offset into the next dirent.

            type[1]
              type of this directory entry.

            name[256]
              name of this directory entry.

    This patch adds v9fs_dir_readdir_dotl() as the readdir() call for 9p2000.L.
    This function sends P9_TREADDIR command to the server. In response the server
    sends a buffer filled with dirent structures. This is different from the
    existing v9fs_dir_readdir() call which receives stat structures from the server.
    This results in significant speedup of readdir() on large directories.
    For example, doing 'ls >/dev/null' on a directory with 10000 files on my
    laptop takes 1.088 seconds with the existing code, but only takes 0.339 seconds
    with the new readdir.
Signed-off-by: NSripathi Kodi <sripathik@in.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Change the v9fs_file_readn function to limit the maximum transfer size
based on the iounit or msize.

Also remove the redundant check for limiting the transfer size in
v9fs_file_write. This check is done by p9_client_write.
Signed-off-by: NM. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Pass the correct end of the buffer to p9stat_read.
Signed-off-by: NLatchesar Ionkov <lucho@ionkov.net>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This patch removes a redundant fid clone on the directory fid and hence
reduces a server transaction while creating new filesystem object.
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

We never use "v9ses" and so we can remove it.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Without this patch, an attempt to mksock will get an EINVAL.

Before this patch:
[root@localhost 1dir]# mksock mysock
mksock: error making mysock: Invalid argument

With this patch:
[root@localhost 1dir]# mksock mysock
[root@localhost 1dir]# ls    -l mysock
s--------- 1 root root 0 2010-03-31 17:44 mysock
Signed-off-by: NVenkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

For lookup if we get ENOENT error from the server we still
instantiate the dentry. We need to make sure we have dentry
operations set in that case so that a later dput on the dentry
does the expected. Without the patch we get the below error

#ln  -sf abc abclink
ln: creating symbolic link `abclink': No such file or directory

Now on the host do
$ touch abclink

Guest now gives ENOENT error.
# ls
ls: cannot access abclink: No such file or directory
Debugged-by: NGautham R Shenoy <ego@in.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>