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: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <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: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric 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: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric 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: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric 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: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Reviewed-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric 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: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric 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: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric 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: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbegren <ericvh@gmail.com>
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: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric 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: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric 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:Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
I made a V2 of this patch on top of my patches for VFS switches.
All the changes were due to change in some offsets.
rename - change name of file or directory
size[4] Trename tag[2] fid[4] newdirfid[4] name[s]
size[4] Rrename tag[2]
The rename message is used to change the name of a file, possibly moving it
to a new directory. The 9P wstat message can only rename a file within the
same directory.
Signed-off-by: Jim Garlick <garlick@llnl.gov>
Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Implements VFS switches for 9p2000.L protocol.
Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
9p: saving negative to unsigned char
9p: return on mutex_lock_interruptible()
9p: Creating files with names too long should fail with ENAMETOOLONG.
9p: Make sure we are able to clunk the cached fid on umount
9p: drop nlink remove
fs/9p: Clunk the fid resulting from partial walk of the name
9p: documentation update
9p: Fix setting of protocol flags in v9fs_session_info structure.
We need to drop the link count on the inode of a sucessfull remove
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
For regular file and directories we put the link
count in th extension field in a tagged string format.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Add 9P2000.u and 9P2010.L protocol flags to V9FS VFS
This patch adds 9P2000.u and 9P2010.L protocol flags into V9FS VFS side code
and removes the single flag used for 'extended'.
Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric 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: Venkateswararao Jujjuri (JV) <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
For symlinks generic_readlink() will work just fine and for directories
we don't want ->readlink() at all.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
I do not know if you've looked on the patch, but unfortunately it is
incorrect. A suggested better version is in this email (the old
version didn't work in case the user provided buffer was not long
enough - it incorrectly appended null byte on a position of last char,
and thus broke the contract of the readlink method). However, I'm
still not sure this is 100% correct thing to do, I think readlink is
supposed to return buffer without last null byte in all cases, but we
do return last null byte (even the old version).. on the other hand it
is likely unspecified what is in the remaining part of the buffer, so
null character may be fine there ;):
Signed-off-by: Martin Stava <martin.stava@gmail.com>
Signed-off-by: Eric 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: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Change all occurrence of inode->i_size with i_size_read() or i_size_write()
as appropriate.
Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Cast the error return value (ENOMEM) in v9fs_get_inode() to its
correct type using ERR_PTR.
Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Add missing p9stat_free in v9fs_inode_from_fid to avoid
any possible leaks.
Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Fix the comments -- mostly the improper and/or missing descriptions
of function parameters.
Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Add a missing iput when cleaning up if v9fs_get_inode
fails after returning a valid inode.
Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Check if v9fs_fid_add was successful or not based on its
return value.
Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
d_iname is rubbish for long file names.
Use d_name.name in printks instead.
Signed-off-by: Wu Fengguang <wfg@linux.intel.com>
Acked-by: Eric Van Hensbergen <ericvh@gmail.com>
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.
Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Reviewed-by: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: v9fs-developer@lists.sourceforge.net
Signed-off-by: James Morris <jmorris@namei.org>
In v9fs_get_inode(), for block, as well as char devices (in theory),
the function init_special_inode() is called to set up callback functions
for file ops. this function uses the file mode's value to determine whether
to use block or char dev functions. In v9fs_inode_from_fid(), the function
p9mode2unixmode() is used, but for all devices it initially returns S_IFBLK,
then uses v9fs_get_inode() to initialise a new inode, then finally uses
v9fs_stat2inode(), which would determine whether the inode is a block or
character device. However, at that point init_special_inode() had already
decided to use the block device functions, so even if the inode's mode is
turned to a character device, the block functions are still used to operate
on them. The attached patch simply calls init_special_inode() again for devices
after parsing device node data in v9fs_stat2inode() so that the proper functions
are used.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Now that the new protocol functions are in place, this patch switches
the client code to using the new support code.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
In case of error, the function p9_client_walk returns an ERR pointer, but
never returns a NULL pointer. So a NULL test that comes after an IS_ERR
test should be deleted.
The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@match_bad_null_test@
expression x, E;
statement S1,S2;
@@
x = p9_client_walk(...)
... when != x = E
* if (x != NULL)
S1 else S2
// </smpl>
Signed-off-by: Julien Brunel <brunel@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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: Eric Van Hensbergen <ericvh@gmail.com>
The kernel-doc comments of much of the 9p system have been in disarray since
reorganization. This patch fixes those problems, adds additional documentation
and a template book which collects the 9p information.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
GDM gets unhappy if /var/gdm doesn't have the sticky bit set. This patch adds
support for the sticky bit in much the same way setuid/setgid is supported.
With this patch, I can launch X from a v9fs rootfs (although I quickly run out
of fds in the server once gnome starts up).
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Acked-by: Eric Van Hensbergen <ericvh@gmail.com>
In v9fs_vfs_rename function labels don't match the fids that are clunked.
The correct clunk order is clunking newdirfid first and then olddirfid next.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
The 9P2000 protocol requires the authentication and permission checks to be
done in the file server. For that reason every user that accesses the file
server tree has to authenticate and attach to the server separately.
Multiple users can share the same connection to the server.
Currently v9fs does a single attach and executes all I/O operations as a
single user. This makes using v9fs in multiuser environment unsafe as it
depends on the client doing the permission checking.
This patch improves the 9P2000 support by allowing every user to attach
separately. The patch defines three modes of access (new mount option
'access'):
- attach-per-user (access=user) (default mode for 9P2000.u)
If a user tries to access a file served by v9fs for the first time, v9fs
sends an attach command to the server (Tattach) specifying the user. If
the attach succeeds, the user can access the v9fs tree.
As there is no uname->uid (string->integer) mapping yet, this mode works
only with the 9P2000.u dialect.
- allow only one user to access the tree (access=<uid>)
Only the user with uid can access the v9fs tree. Other users that attempt
to access it will get EPERM error.
- do all operations as a single user (access=any) (default for 9P2000)
V9fs does a single attach and all operations are done as a single user.
If this mode is selected, the v9fs behavior is identical with the current
one.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Change the names of 'uid' and 'gid' parameters to the more appropriate
'dfltuid' and 'dfltgid'. This also sets the default uid/gid to -2
(aka nfsnobody)
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Create more general flags field in the v9fs_session_info struct and move the
'extended' flag as a bit in the flags.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
This patch expands the impact of the loose cache mode to allow for cached
metadata increasing the performance of directory listings and other metadata
read operations.
Signed-off-by: Eric 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: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.
This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly
Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).
Cross-compile tested on
all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig
as well as my two usual configs.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
v9fs_insert uses v9fs_fid_lookup (which also locks the fid) to get the
primary fid associated with the dentry and destroys the v9fs_fid struct
after removing the file. If another process called v9fs_fid_lookup on the
same dentry, it may wait undefinitely for the fid's lock (as the struct is
freed).
This patch changes v9fs_remove to use a cloned fid, so the primary fid is
not locked and freed.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@hera.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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: Eric Van Hensbergen <ericvh@gmail.com>
Many struct inode_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a double free of "dfid" introduced by commit
da977b2c7e and spotted by the Coverity
checker.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Running dbench multithreaded exposed a race condition where fid structures
were removed while in use. This patch adds semaphores to meta-data operations
to protect the fid structure. Some cleanup of error-case handling in the
inode operations is also included.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9p doesn't handle renames between directories -- however, we were returning
EPERM instead of EXDEV when we detected this case.
Signed-off-by: Eric Van Hensbergren <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Function v9fs_get_idpool returns int, not u32. Actually it returns -1 on
errors, and these two callers check if the value is smaller than 0, which
was caught by gcc with extra warning flags. Compile tested only but should
be OK, as the value computed in v9fs_get_idpool() is also int.
Signed-of-by: Mika Kukkonen <mikukkon@iki.fi>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@lanl.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is mostly included for parity with dec_nlink(), where we will have some
more hooks. This one should stay pretty darn straightforward for now.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This eliminates the i_blksize field from struct inode. Filesystems that want
to provide a per-inode st_blksize can do so by providing their own getattr
routine instead of using the generic_fillattr() function.
Note that some filesystems were providing pretty much random (and incorrect)
values for i_blksize.
[bunk@stusta.de: cleanup]
[akpm@osdl.org: generic_fillattr() fix]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Based on a bug report from Russ Ross <russruss@gmail.com>
According to the spec:
"The remove request asks the file server both to remove the file
represented by fid and to clunk the fid, even if the remove fails."
but the Linux client seems to expect the fid to be valid after a failed
remove attempt. Specifically, I'm getting this behavior when attempting to
remove a non-empty directory.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix an incorrect check whether a fid was allocated in v9fs_create and if it
should be freed on error.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
coverity found two needless checks in vfs_inode.c (cid #1165 and #1164)
In both cases inode is always NULL when we goto error; either because it
is still initialized to NULL or is set to NULL explicitly. This patch
simply removes these checks to save some code.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Acked-by: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@lanl.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Multiple races can happen when v9fs is interrupted by a signal and Tflush
message is sent to the server. After v9fs sends Tflush it doesn't wait
until it receives Rflush, and possibly the response of the original
message. This behavior may confuse v9fs what fids are allocated by the
file server.
This patch fixes the races and the fid allocation.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@hera.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus 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: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
__getname, which in turn will call kmem_cache_alloc, may return NULL.
Coverity bug #977
Signed-off-by: Eugene Teo <eugene.teo@eugeneteo.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Implement a new way of creating special files. Instead of Tcreate+Twstat,
add one more field to Tcreate that contains special file description.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If a file is not found in v9fs_vfs_lookup, the function creates negative
dentry, but doesn't assign any dentry ops. This leaves the negative entry
in the cache (there is no d_delete to mark it for removal). If the file is
created outside of the mounted v9fs filesystem, the file shows up in the
directory with weird permissions.
This patch assigns the default v9fs dentry ops to the negative dentry.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Miscellaneous fixes related to accessing uninitialized variables or memory
that was already freed.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus 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: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Two symlink fixes, v9fs_readlink didn't copy the last character of the
symlink name, v9fs_vfs_follow_link incorrectly called strlen of newly
allocated buffer instead of PATH_MAX.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus 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: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- remove unnecessary -ENOMEM assignments
- return correct value when buf_check_size for second time in a buffer
- handle failures when create_workqueue and kthread_create are called
- use kzalloc instead of kmalloc/memset 0
- v9fs_str_copy and v9fs_str_compare were buggy, were used only in one
place, correct the logic and move it to the place it is used.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Performance enhancement reducing the number of copies in the data and
stat paths.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
v9fs_create doesn't manage correctly the fids when it is called to create a
directory.. The fid created by the create 9P call (newfid) and the one
created by walking to already created file (wfidno) are not used
consistently.
This patch cleans up the usage of newfid and wfidno.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
New multiplexer implementation. Decreases the number of kernel threads
required. Better handling when the user process receives a signal.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Assign the appropriate dentry operations to the dentry. Fixes memory leak.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Data allocated with "__getname()" should always be free'd with "__putname()"
because of the AUDITSYSCALL code.
Signed-off-by: Davi Arnaut <davi.arnaut@gmail.com>
Cc: <rminnich@lanl.gov>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fid management cleanup. The patch attempts to fix the races in dentry's
fid management.
Dentries don't keep the opened fids anymore, they are moved to the file
structs. Ideally there should be no more than one fid with fidcreate equal
to zero in the dentry's list of fids.
v9fs_fid_create initializes the important fields (fid, fidcreated) before
v9fs_fid is added to the list. v9fs_fid_lookup returns only fids that are
not created by v9fs_create. v9fs_fid_get_created returns the fid created
by the same process by v9fs_create (if any) and removes it from dentry's
list
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
v9fs_vfs_readlink allocates space for the link using __getname and
errorneously uses strlen on the newly allocated buffer to check if the buffer
passed by the user is bigger than the one returned by __getname.
The patch replaces the strlen usage to PATH_MAX, which is the actual size of
the buffers returned by __getname.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
LANL reported some issues with random crashes during mount of legacy protocol
servers (9P2000 versus 9P2000.u) -- crash was always happening in readlink
(which should never happen in legacy mode). Added some sanity conditionals to
the get_inode code which should prevent the errors LANL was seeing. Code
tested benign through regression.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Cleanup code in v9fs vfs_inode as suggested by Alexey Dobriyan. Did some
major revamping of the v9fs setattr code to remove unnecessary allocations and
clean up some dead-code.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains the VFS inode interfaces.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Aneesh Kumar K.V