This is largely derived from existing Darwin support. FreeBSD
apparently has better support for *at() system calls so doesn't require
workarounds for a missing mknodat(). The implementation has a couple of
warts however:
- The extattr(2) system calls don't support anything akin to
XATTR_CREATE or XATTR_REPLACE, so a racy workaround is implemented.
- Attribute names cannot begin with "user." or "system." on ZFS.
However FreeBSD's extattr(2) system calls support two dedicated
namespaces for these two. So "user." or "system." prefixes are
trimmed off from attribute names and instead EXTATTR_NAMESPACE_USER or
EXTATTR_NAMESPACE_SYSTEM are picked and passed to extattr system calls
accordingly.
The 9pfs tests were verified to pass on the UFS, ZFS and tmpfs
filesystems.
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Link: https://lore.kernel.org/qemu-devel/aJOWhHB2p-fbueAm@nuc
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Add an futimens operation to the fs driver and use if when a fid has
a valid file descriptor. This is required to support more cases where
the client wants to do an action on an unlinked file which it still
has an open file decriptor for.
Only 9P2000.L was considered.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20250312152933.383967-5-groug@kaod.org>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Add an ftruncate operation to the fs driver and use if when a fid has
a valid file descriptor. This is required to support more cases where
the client wants to do an action on an unlinked file which it still
has an open file decriptor for.
Only 9P2000.L was considered.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20250312152933.383967-4-groug@kaod.org>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
v9fs_getattr() currently peeks into V9fsFidOpenState to know if a fid
has a valid file descriptor or directory stream. Even though the fields
are accessible, this is an implementation detail of the local backend
that should not be manipulated directly by the server code.
Abstract that with a new has_valid_file_handle() backend operation.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20250312152933.383967-3-groug@kaod.org>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
- Guard Linux only headers.
- Add qemu/statfs.h header to abstract over the which
headers are needed for struct statfs
- Define `ENOATTR` only if not only defined
(it's defined in system headers on Darwin).
Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
While it might at first appear that fsdev/virtfs-proxy-header.c would
need similar adjustment for darwin as file-op-9p here, a later patch in
this series disables virtfs-proxy-helper for non-Linux. Allowing
virtfs-proxy-helper on darwin could potentially be an additional
optimization later.
[Will Cohen: - Fix headers for Alpine
- Integrate statfs.h back into file-op-9p.h
- Remove superfluous header guards from file-opt-9p
- Add note about virtfs-proxy-helper being disabled
on non-Linux for this patch series]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20220227223522.91937-2-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
I found some style problems while check the code using checkpatch.pl.
This commit fixs the issue below:
ERROR: open brace '{' following struct go on the same line
Signed-off-by: zhouyang <zhouyang789@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201209060735.2760943-1-zhouyang789@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Previous patch introduced a performance warning being logged on host
side if client connected with an 'msize' <= 8192. Disable this
performance warning for the synth driver to prevent that warning from
being printed whenever the 9pfs (qtest) test cases are running.
Introduce a new export flag V9FS_NO_PERF_WARN for that purpose, which
might also be used to disable such warnings from the CLI in future.
We could have also prevented the warning by simply raising P9_MAX_SIZE
in virtio-9p-test.c to any value larger than 8192, however in the
context of test cases it makes sense running for edge cases, which
includes the lowest 'msize' value supported by the server which is
4096, hence we want to preserve an msize of 4096 for the test client.
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1kEyDy-0006nN-5A@lizzy.crudebyte.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
'warn' (default): Only log an error message (once) on host if more than one
device is shared by same export, except of that just ignore this config
error though. This is the default behaviour for not breaking existing
installations implying that they really know what they are doing.
'forbid': Like 'warn', but except of just logging an error this
also denies access of guest to additional devices.
'remap': Allows to share more than one device per export by remapping
inodes from host to guest appropriately. To support multiple devices on the
9p share, and avoid qid path collisions we take the device id as input to
generate a unique QID path. The lowest 48 bits of the path will be set
equal to the file inode, and the top bits will be uniquely assigned based
on the top 16 bits of the inode and the device id.
Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com>
[CS: - Rebased to https://github.com/gkurz/qemu/commits/9p-next
(SHA1 7fc4c49e91).
- Added virtfs option 'multidevs', original patch simply did the inode
remapping without being asked.
- Updated hash calls to new xxhash API.
- Updated docs for new option 'multidevs'.
- Fixed v9fs_do_readdir() not having remapped inodes.
- Log error message when running out of prefixes in
qid_path_prefixmap().
- Fixed definition of QPATH_INO_MASK.
- Wrapped qpp_table initialization to dedicated qpp_table_init()
function.
- Dropped unnecessary parantheses in qpp_lookup_func().
- Dropped unnecessary g_malloc0() result checks. ]
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
[groug: - Moved "multidevs" parsing to the local backend.
- Added hint to invalid multidevs option error.
- Turn "remap" into "x-remap". ]
Signed-off-by: Greg Kurz <groug@kaod.org>
This patch changes some error messages in the backend init code and
convert backends to propagate QEMU Error objects instead of calling
error_report().
One notable improvement is that the local backend now provides a more
detailed error report when it fails to open the shared directory.
Signed-off-by: Greg Kurz <groug@kaod.org>
This patch changes some error messages in the backend opts parsing
code and convert backends to propagate QEMU Error objects instead
of calling error_report().
Signed-off-by: Greg Kurz <groug@kaod.org>
In mapped security modes, files are created with very restrictive
permissions (600 for files and 700 for directories). This makes
file sharing between virtual machines and users on the host rather
complicated. Imagine eg. a group of users that need to access data
produced by processes on a virtual machine. Giving those users access
to the data will be difficult since the group access mode is always 0.
This patch makes the default mode for both files and directories
configurable. Existing setups that don't know about the new parameters
keep using the current secure behavior.
Signed-off-by: Tobias Schramm <tobleminer@gmail.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
This patchset adds the throttle support for the 9p-local driver.
For now this functionality can be enabled only through qemu cli options.
QMP interface and support to other drivers need further extensions.
To make it simple for other 9p drivers, the throttle code has been put in
separate files.
Signed-off-by: Pradeep Jagadeesh <pradeep.jagadeesh@huawei.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
(pass extra NULL CoMutex * argument to qemu_co_queue_wait(),
added options to qemu-options.hx, Greg Kurz)
Signed-off-by: Greg Kurz <groug@kaod.org>
Currently, the backend of VirtFS doesn't have a cleanup
function. This will lead resource leak issues if the backed
driver allocates resources. This patch addresses this issue.
Signed-off-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
Header guard symbols should match their file name to make guard
collisions less likely. Offenders found with
scripts/clean-header-guards.pl -vn.
Cleaned up with scripts/clean-header-guards.pl, followed by some
renaming of new guard symbols picked by the script to better ones.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
The <sys/uio.h> system header doesn't exist on all host platforms. Code
should include "qemu/osdep.h" instead to avoid build breaks on plafforms
that don't define CONFIG_IOVEC (like win32, if it is to support 9p one day).
Acked-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Michael Fritscher <michael@fritscher.net>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
This patch changes the 9p code to use readdir() again instead of
readdir_r(), which is deprecated in glibc 2.24.
All the locking was put in place by a previous patch.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Most of the 9p code is now virtio agnostic. This patch does a final cleanup:
- drop references to Virtio from the header comments
- fix includes
Also drop a couple of leading empty lines while here.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
This enable us to do passthrough equivalent security model on NFS directory.
NFS server mostly do root squashing and don't support xattr. Hence we cannot
use 'passthrough' or 'mapped' security model
Also added "mapped-xattr" security to indicate earlier "mapped" security model
Older name is still supported.
POSIX rules regarding ctime update on chmod are not followed by this security model.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Add option to use named socket for communicating between proxy helper
and qemu proxy FS. Access to socket can be given by using command line
options -u and -g.
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
This remove all conditional code from common code path and
make opt validation a FSDriver callback.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Fsdriver callback that operate on file descriptor need to
differentiate between directory fd and file fd.
Based on the original patch from Sassan Panahinejad <sassan@sassan.me.uk>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
To implement synthetic file system in Qemu we may not really
require file descriptor and Dir *. Make generic code use
V9fsFidOpenState instead.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
A new fsdev parameter "readonly" is introduced to control accessing 9p export.
"readonly" can be used to specify the access type. By default "rw" access
is given to 9p export.
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
This patch use file system specific ioctl for getting i_generation
value. Not all file system support the ioctl. So we add an export
specific extended operation and assign right callback for the
file system that support i_generation ioctl
["M. Mohan Kumar" <mohan@in.ibm.com> we can do ioctl only for
regular files and directories on the server]
Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
writeout=immediate implies the after pwritev we do a sync_file_range.
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Add a new context flag PATHNAME_FSCONTEXT and indicate whether
the fs driver track fid using path names. Also add a private
pointer that help us to track fs driver specific values in there
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
This enables us to add handles to track fids later. The
V9fsPath added is similar to V9fsString except that the
size include the NULL byte also.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Current rpath inline function is heavily used in all system calls.
This function has a static buffer making it a non-thread safe function.
This patch introduces new thread-safe routine and makes use of it.
Signed-off-by: Venkateswararao Jujjuri "<jvrao@linux.vnet.ibm.com>
Now that we start adding more files related to 9pfs
it make sense to move them to a separate directory
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
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: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
readv & writev, read & write respectively from the current offset
of the file & hence their use has to be preceeded by a call to lseek.
preadv/writev can be used instead, as they take the offset as an argument.
This saves one system call( lseek ).
In case preadv is not supported, it is implemented by an lseek
followed by a readv. Depending upon the configuration of QEMU, the
appropriate read & write methods are selected. This patch also fixes the
zero byte read/write bug & obviates the need to apply a fix for that bug separately.
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Sanchit Garg <sancgarg@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
We would need this to make sure we handle the mapped
security model correctly for different xattr names.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
This is equivalent to SM_PASSTHROUGH security model.
The only exception is, failure of privilige operation like chown
are ignored. This makes a passthrough like security model usable
for people who runs kvm as non root
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
TXATTRCREATE: Prepare a fid for setting xattr value on a file system object.
size[4] TXATTRCREATE tag[2] fid[4] name[s] attr_size[8] flags[4]
size[4] RXATTRWALK tag[2]
txattrcreate gets a fid pointing to xattr. This fid can later be
used to get set the xattr value.
flag value is derived from set Linux setxattr. The manpage says
"The flags parameter can be used to refine the semantics of the operation.
XATTR_CREATE specifies a pure create, which fails if the named attribute
exists already. XATTR_REPLACE specifies a pure replace operation, which
fails if the named attribute does not already exist. By default (no flags),
the extended attribute will be created if need be, or will simply replace
the value if the attribute exists."
The actual setxattr operation happens when the fid is clunked. At that point
the written byte count and the attr_size specified in TXATTRCREATE should be
same otherwise an error will be returned.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
TXATTRWALK: Descend a ATTR namespace
size[4] TXATTRWALK tag[2] fid[4] newfid[4] name[s]
size[4] RXATTRWALK tag[2] size[8]
txattrwalk gets a fid pointing to xattr. This fid can later be
used to get read the xattr value. If name is NULL the fid returned
can be used to get the list of extended attribute associated to
the file system object.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Current code resets file's atime to 0 when there is a change in mtime.
This results in resetting the atime to "1970-01-01 05:30:00". For
example, truncate -s 0 filename results in changing the mtime to the
truncate time, but resets the atime to "1970-01-01 05:30:00". utime
system call does not have any provision to set only mtime or atime. So
change v9fs_wstat_post_chmod function to use utimensat function to change
the atime and mtime fields. If tv_nsec field is set to the special value
"UTIME_OMIT", corresponding file time stamp is not updated.
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Implement statfs support in qemu server based on Sripathi's
initial statfs patch.
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Mark Johnston
Greg Kurz
Keno Fischer
Christian Schoenebeck
zhouyang
Antonios Motakis
Tobias Schramm
Pradeep Jagadeesh
Li Qiang
Markus Armbruster
Greg Kurz
Peter Maydell
Aneesh Kumar K.V
M. Mohan Kumar
Harsh Prateek Bora
Venkateswararao Jujjuri (JV)
Blue Swirl
Sanchit Garg