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2019-03-22trace-events: Fix attribution of trace points to sourceMarkus Armbruster
Some trace points are attributed to the wrong source file. Happens when we neglect to update trace-events for code motion, or add events in the wrong place, or misspell the file name. Clean up with help of cleanup-trace-events.pl. Same funnies as in the previous commit, of course. Manually shorten its change to linux-user/trace-events to */signal.c. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-id: 20190314180929.27722-6-armbru@redhat.com Message-Id: <20190314180929.27722-6-armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-03-22trace-events: Shorten file names in commentsMarkus Armbruster
We spell out sub/dir/ in sub/dir/trace-events' comments pointing to source files. That's because when trace-events got split up, the comments were moved verbatim. Delete the sub/dir/ part from these comments. Gets rid of several misspellings. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-id: 20190314180929.27722-3-armbru@redhat.com Message-Id: <20190314180929.27722-3-armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-03-07virtio: express virtio dependencies with KconfigYang Zhong
Signed-off-by: Yang Zhong <yang.zhong@intel.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Message-Id: <20190123065618.3520-42-yang.zhong@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-07build: switch to KconfigPaolo Bonzini
The make_device_config.sh script is replaced by minikconf, which is modified to support the same command line as its predecessor. The roots of the parsing are default-configs/*.mak, Kconfig.host and hw/Kconfig. One difference with make_device_config.sh is that all symbols have to be defined in a Kconfig file, including those coming from the configure script. This is the reason for the Kconfig.host file introduced in the previous patch. Whenever a file in default-configs/*.mak used $(...) to refer to a config-host.mak symbol, this is replaced by a Kconfig dependency; this part must be done already in this patch for bisectability. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Yang Zhong <yang.zhong@intel.com> Acked-by: Thomas Huth <thuth@redhat.com> Message-Id: <20190123065618.3520-28-yang.zhong@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-07kconfig: introduce kconfig filesPaolo Bonzini
The Kconfig files were generated mostly with this script: for i in `grep -ho CONFIG_[A-Z0-9_]* default-configs/* | sort -u`; do set fnord `git grep -lw $i -- 'hw/*/Makefile.objs' ` shift if test $# = 1; then cat >> $(dirname $1)/Kconfig << EOF config ${i#CONFIG_} bool EOF git add $(dirname $1)/Kconfig else echo $i $* fi done sed -i '$d' hw/*/Kconfig for i in hw/*; do if test -d $i && ! test -f $i/Kconfig; then touch $i/Kconfig git add $i/Kconfig fi done Whenever a symbol is referenced from multiple subdirectories, the script prints the list of directories that reference the symbol. These symbols have to be added manually to the Kconfig files. Kconfig.host and hw/Kconfig were created manually. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Yang Zhong <yang.zhong@intel.com> Message-Id: <20190123065618.3520-27-yang.zhong@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-079pfs: remove unnecessary conditionalsPaolo Bonzini
The VIRTIO_9P || VIRTFS && XEN condition can be computed in hw/Makefile.objs, removing an "if" from hw/9pfs/Makefile.objs. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-14xen: re-name XenDevice to XenLegacyDevice...Paul Durrant
...and xen_backend.h to xen-legacy-backend.h Rather than attempting to convert the existing backend infrastructure to be QOM compliant (which would be hard to do in an incremental fashion), subsequent patches will introduce a completely new framework for Xen PV backends. Hence it is necessary to re-name parts of existing code to avoid name clashes. The re-named 'legacy' infrastructure will be removed once all backends have been ported to the new framework. This patch is purely cosmetic. No functional change. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2018-12-129p: remove support for the "handle" backendGreg Kurz
The "handle" fsdev backend was deprecated in QEMU 2.12.0 with: commit db3b3c7281ca82e2647e072a1f97db111313dd73 Author: Greg Kurz <groug@kaod.org> Date: Mon Jan 8 11:18:23 2018 +0100 9pfs: deprecate handle backend This backend raise some concerns: - doesn't support symlinks - fails +100 tests in the PJD POSIX file system test suite [1] - requires the QEMU process to run with the CAP_DAC_READ_SEARCH capability, which isn't recommended for security reasons This backend should not be used and wil be removed. The 'local' backend is the recommended alternative. [1] https://www.tuxera.com/community/posix-test-suite/ Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> It has passed the two release cooling period without any complaint. Remove it now. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Thomas Huth <thuth@redhat.com>
2018-12-12xen/9pfs: use g_new(T, n) instead of g_malloc(sizeof(T) * n)Greg Kurz
Because it is a recommended coding practice (see HACKING). Signed-off-by: Greg Kurz <groug@kaod.org> Acked-by: Anthony PERARD <anthony.perard@citrix.com>
2018-12-129p: use g_new(T, n) instead of g_malloc(sizeof(T) * n)Greg Kurz
Because it is a recommended coding practice (see HACKING). Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2018-11-239p: fix QEMU crash when renaming filesGreg Kurz
When using the 9P2000.u version of the protocol, the following shell command line in the guest can cause QEMU to crash: while true; do rm -rf aa; mkdir -p a/b & touch a/b/c & mv a aa; done With 9P2000.u, file renaming is handled by the WSTAT command. The v9fs_wstat() function calls v9fs_complete_rename(), which calls v9fs_fix_path() for every fid whose path is affected by the change. The involved calls to v9fs_path_copy() may race with any other access to the fid path performed by some worker thread, causing a crash like shown below: Thread 12 "qemu-system-x86" received signal SIGSEGV, Segmentation fault. 0x0000555555a25da2 in local_open_nofollow (fs_ctx=0x555557d958b8, path=0x0, flags=65536, mode=0) at hw/9pfs/9p-local.c:59 59 while (*path && fd != -1) { (gdb) bt #0 0x0000555555a25da2 in local_open_nofollow (fs_ctx=0x555557d958b8, path=0x0, flags=65536, mode=0) at hw/9pfs/9p-local.c:59 #1 0x0000555555a25e0c in local_opendir_nofollow (fs_ctx=0x555557d958b8, path=0x0) at hw/9pfs/9p-local.c:92 #2 0x0000555555a261b8 in local_lstat (fs_ctx=0x555557d958b8, fs_path=0x555556b56858, stbuf=0x7fff84830ef0) at hw/9pfs/9p-local.c:185 #3 0x0000555555a2b367 in v9fs_co_lstat (pdu=0x555557d97498, path=0x555556b56858, stbuf=0x7fff84830ef0) at hw/9pfs/cofile.c:53 #4 0x0000555555a1e9e2 in v9fs_stat (opaque=0x555557d97498) at hw/9pfs/9p.c:1083 #5 0x0000555555e060a2 in coroutine_trampoline (i0=-669165424, i1=32767) at util/coroutine-ucontext.c:116 #6 0x00007fffef4f5600 in __start_context () at /lib64/libc.so.6 #7 0x0000000000000000 in () (gdb) The fix is to take the path write lock when calling v9fs_complete_rename(), like in v9fs_rename(). Impact: DoS triggered by unprivileged guest users. Fixes: CVE-2018-19489 Cc: P J P <ppandit@redhat.com> Reported-by: zhibin hu <noirfate@gmail.com> Reviewed-by: Prasad J Pandit <pjp@fedoraproject.org> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-11-209p: take write lock on fid path updates (CVE-2018-19364)Greg Kurz
Recent commit 5b76ef50f62079a fixed a race where v9fs_co_open2() could possibly overwrite a fid path with v9fs_path_copy() while it is being accessed by some other thread, ie, use-after-free that can be detected by ASAN with a custom 9p client. It turns out that the same can happen at several locations where v9fs_path_copy() is used to set the fid path. The fix is again to take the write lock. Fixes CVE-2018-19364. Cc: P J P <ppandit@redhat.com> Reported-by: zhibin hu <noirfate@gmail.com> Reviewed-by: Prasad J Pandit <pjp@fedoraproject.org> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-11-089p: write lock path in v9fs_co_open2()Greg Kurz
The assumption that the fid cannot be used by any other operation is wrong. At least, nothing prevents a misbehaving client to create a file with a given fid, and to pass this fid to some other operation at the same time (ie, without waiting for the response to the creation request). The call to v9fs_path_copy() performed by the worker thread after the file was created can race with any access to the fid path performed by some other thread. This causes use-after-free issues that can be detected by ASAN with a custom 9p client. Unlike other operations that only read the fid path, v9fs_co_open2() does modify it. It should hence take the write lock. Cc: P J P <ppandit@redhat.com> Reported-by: zhibin hu <noirfate@gmail.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-10-19fsdev: Clean up error reporting in qemu_fsdev_add()Markus Armbruster
Calling error_report() from within a function that takes an Error ** argument is suspicious. qemu_fsdev_add() does that, and its caller fsdev_init_func() then fails without setting an error. Its caller main(), via qemu_opts_foreach(), is fine with it, but clean it up anyway. Cc: Greg Kurz <groug@kaod.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Acked-by: Greg Kurz <groug@kaod.org> Message-Id: <20181017082702.5581-32-armbru@redhat.com>
2018-10-199pfs: Fix CLI parsing crash on errorMarkus Armbruster
Calling error_report() in a function that takes an Error ** argument is suspicious. 9p-handle.c's handle_parse_opts() does that, and then fails without setting an error. Wrong. Its caller crashes when it tries to report the error: $ qemu-system-x86_64 -nodefaults -fsdev id=foo,fsdriver=handle qemu-system-x86_64: -fsdev id=foo,fsdriver=handle: warning: handle backend is deprecated qemu-system-x86_64: -fsdev id=foo,fsdriver=handle: fsdev: No path specified Segmentation fault (core dumped) Screwed up when commit 91cda4e8f37 (v2.12.0) converted the function to Error. Fix by calling error_setg() instead of error_report(). Fixes: 91cda4e8f372602795e3a2f4bd2e3adaf9f82255 Cc: Greg Kurz <groug@kaod.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Acked-by: Greg Kurz <groug@kaod.org> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20181017082702.5581-9-armbru@redhat.com>
2018-10-19error: Fix use of error_prepend() with &error_fatal, &error_abortMarkus Armbruster
From include/qapi/error.h: * Pass an existing error to the caller with the message modified: * error_propagate(errp, err); * error_prepend(errp, "Could not frobnicate '%s': ", name); Fei Li pointed out that doing error_propagate() first doesn't work well when @errp is &error_fatal or &error_abort: the error_prepend() is never reached. Since I doubt fixing the documentation will stop people from getting it wrong, introduce error_propagate_prepend(), in the hope that it lures people away from using its constituents in the wrong order. Update the instructions in error.h accordingly. Convert existing error_prepend() next to error_propagate to error_propagate_prepend(). If any of these get reached with &error_fatal or &error_abort, the error messages improve. I didn't check whether that's the case anywhere. Cc: Fei Li <fli@suse.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20181017082702.5581-2-armbru@redhat.com>
2018-06-299p: darwin: Explicitly cast comparisons of mode_t with -1Keno Fischer
Comparisons of mode_t with -1 require an explicit cast, since mode_t is unsigned on Darwin. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-29cutils: Provide strchrnulKeno Fischer
strchrnul is a GNU extension and thus unavailable on a number of targets. In the review for a commit removing strchrnul from 9p, I was asked to create a qemu_strchrnul helper to factor out this functionality. Do so, and use it in a number of other places in the code base that inlined the replacement pattern in a place where strchrnul could be used. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Acked-by: Greg Kurz <groug@kaod.org> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-079p: xattr: Properly translate xattrcreate flagsKeno Fischer
As with unlinkat, these flags come from the client and need to be translated to their host values. The protocol values happen to match linux, but that need not be true in general. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-079p: Properly check/translate flags in unlinkatKeno Fischer
The 9p-local code previously relied on P9_DOTL_AT_REMOVEDIR and AT_REMOVEDIR having the same numerical value and deferred any errorchecking to the syscall itself. However, while the former assumption is true on Linux, it is not true in general. 9p-handle did this properly however. Move the translation code to the generic 9p server code and add an error if unrecognized flags are passed. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-079p: local: Avoid warning if FS_IOC_GETVERSION is not definedKeno Fischer
Both `stbuf` and `local_ioc_getversion` where unused when FS_IOC_GETVERSION was not defined, causing a compiler warning. Reorganize the code to avoid this warning. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-079p: xattr: Fix crashes due to free of uninitialized valueKeno Fischer
If the size returned from llistxattr/lgetxattr is 0, we skipped the malloc call, leaving xattr.value uninitialized. However, this value is later passed to `g_free` without any further checks, causing an error. Fix that by always calling g_malloc unconditionally. If `size` is 0, it will return NULL, which is safe to pass to g_free. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-079p: Move a couple xattr functions to 9p-utilKeno Fischer
These functions will need custom implementations on Darwin. Since the implementation is very similar among all of them, and 9p-util already has the _nofollow version of fgetxattrat, let's move them all there. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-079p: local: Properly set errp in fstatfs error pathKeno Fischer
In the review of 9p: Avoid warning if FS_IOC_GETVERSION is not defined Grep Kurz noted this error path was failing to set errp. Fix that. Signed-off-by: Keno Fischer <keno@juliacomputing.com> [added local: to commit title, Greg Kurz] Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-079p: proxy: Fix size passed to `connect`Keno Fischer
The size to pass to the `connect` call is the size of the entire `struct sockaddr_un`. Passing anything shorter than this causes errors on darwin. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-06-01hw: make virtio devices configurable via default-configs/Paolo Bonzini
This is only half of the work, because the proxy devices (virtio-*-pci, virtio-*-ccw, etc.) are still included unconditionally. It is still a move in the right direction. Based-on: <20180522194943.24871-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-22xen: remove other open-coded use of libxengnttabPaul Durrant
Now that helpers are available in xen_backend, use them throughout all Xen PV backends. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-029p: add trace event for v9fs_setattr()Greg Kurz
Don't print the tv_nsec part of atime and mtime, to stay below the 10 argument limit of trace events. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-02-199p: fix leak in synth_name_to_path()Marc-André Lureau
Leak found thanks to ASAN: Direct leak of 8 byte(s) in 1 object(s) allocated from: #0 0x55995789ac90 in __interceptor_malloc (/home/elmarco/src/qemu/build/x86_64-softmmu/qemu-system-x86_64+0x1510c90) #1 0x7f0a91190f0c in g_malloc /home/elmarco/src/gnome/glib/builddir/../glib/gmem.c:94 #2 0x5599580a281c in v9fs_path_copy /home/elmarco/src/qemu/hw/9pfs/9p.c:196:17 #3 0x559958f9ec5d in coroutine_trampoline /home/elmarco/src/qemu/util/coroutine-ucontext.c:116:9 #4 0x7f0a8766ebbf (/lib64/libc.so.6+0x50bbf) Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-02-199p: v9fs_path_copy() readabilityMarc-André Lureau
lhs/rhs doesn't tell much about how argument are handled, dst/src is and const arguments is clearer in my mind. Use g_memdup() while at it. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Greg Kurz <groug@kaod.org>
2018-02-09Move include qemu/option.h from qemu-common.h to actual usersMarkus Armbruster
qemu-common.h includes qemu/option.h, but most places that include the former don't actually need the latter. Drop the include, and add it to the places that actually need it. While there, drop superfluous includes of both headers, and separate #include from file comment with a blank line. This cleanup makes the number of objects depending on qemu/option.h drop from 4545 (out of 4743) to 284 in my "build everything" tree. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180201111846.21846-20-armbru@redhat.com> [Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
2018-02-09Include qapi/error.h exactly where neededMarkus Armbruster
This cleanup makes the number of objects depending on qapi/error.h drop from 1910 (out of 4743) to 1612 in my "build everything" tree. While there, separate #include from file comment with a blank line, and drop a useless comment on why qemu/osdep.h is included first. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180201111846.21846-5-armbru@redhat.com> [Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
2018-02-02tests: virtio-9p: add FLUSH operation testGreg Kurz
The idea is to send a victim request that will possibly block in the server and to send a flush request to cancel the victim request. This patch adds two test to verifiy that: - the server does not reply to a victim request that was actually cancelled - the server replies to the flush request after replying to the victim request if it could not cancel it 9p request cancellation reference: http://man.cat-v.org/plan_9/5/flush Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> (groug, change the test to only write a single byte to avoid any alignment or endianess consideration)
2018-02-01tests: virtio-9p: add WRITE operation testGreg Kurz
Trivial test of a successful write. Signed-off-by: Greg Kurz <groug@kaod.org> (groug, handle potential overflow when computing request size, add missing g_free(buf), backend handles one written byte at a time to validate the server doesn't do short-reads) Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-02-01tests: virtio-9p: add LOPEN operation testGreg Kurz
Trivial test of a successful open. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-02-01tests: virtio-9p: use the synth backendGreg Kurz
The purpose of virtio-9p-test is to test the virtio-9p device, especially the 9p server state machine. We don't really care what fsdev backend we're using. Moreover, if we want to be able to test the flush request or a device reset with in-flights I/O, it is close to impossible to achieve with a physical backend because we cannot ask it reliably to put an I/O on hold at a specific point in time. Fortunately, we can do that with the synthetic backend, which allows to register callbacks on read/write accesses to a specific file. This will be used by a later patch to test the 9P flush request. The walk request test is converted to using the synth backend. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-02-019pfs: Correctly handle cancelled requestsKeno Fischer
# Background I was investigating spurious non-deterministic EINTR returns from various 9p file system operations in a Linux guest served from the qemu 9p server. ## EINTR, ERESTARTSYS and the linux kernel When a signal arrives that the Linux kernel needs to deliver to user-space while a given thread is blocked (in the 9p case waiting for a reply to its request in 9p_client_rpc -> wait_event_interruptible), it asks whatever driver is currently running to abort its current operation (in the 9p case causing the submission of a TFLUSH message) and return to user space. In these situations, the error message reported is generally ERESTARTSYS. If the userspace processes specified SA_RESTART, this means that the system call will get restarted upon completion of the signal handler delivery (assuming the signal handler doesn't modify the process state in complicated ways not relevant here). If SA_RESTART is not specified, ERESTARTSYS gets translated to EINTR and user space is expected to handle the restart itself. ## The 9p TFLUSH command The 9p TFLUSH commands requests that the server abort an ongoing operation. The man page [1] specifies: ``` If it recognizes oldtag as the tag of a pending transaction, it should abort any pending response and discard that tag. [...] When the client sends a Tflush, it must wait to receive the corresponding Rflush before reusing oldtag for subsequent messages. If a response to the flushed request is received before the Rflush, the client must honor the response as if it had not been flushed, since the completed request may signify a state change in the server ``` In particular, this means that the server must not send a reply with the orignal tag in response to the cancellation request, because the client is obligated to interpret such a reply as a coincidental reply to the original request. # The bug When qemu receives a TFlush request, it sets the `cancelled` flag on the relevant pdu. This flag is periodically checked, e.g. in `v9fs_co_name_to_path`, and if set, the operation is aborted and the error is set to EINTR. However, the server then violates the spec, by returning to the client an Rerror response, rather than discarding the message entirely. As a result, the client is required to assume that said Rerror response is a result of the original request, not a result of the cancellation and thus passes the EINTR error back to user space. This is not the worst thing it could do, however as discussed above, the correct error code would have been ERESTARTSYS, such that user space programs with SA_RESTART set get correctly restarted upon completion of the signal handler. Instead, such programs get spurious EINTR results that they were not expecting to handle. It should be noted that there are plenty of user space programs that do not set SA_RESTART and do not correctly handle EINTR either. However, that is then a userspace bug. It should also be noted that this bug has been mitigated by a recent commit to the Linux kernel [2], which essentially prevents the kernel from sending Tflush requests unless the process is about to die (in which case the process likely doesn't care about the response). Nevertheless, for older kernels and to comply with the spec, I believe this change is beneficial. # Implementation The fix is fairly simple, just skipping notification of a reply if the pdu was previously cancelled. We do however, also notify the transport layer that we're doing this, so it can clean up any resources it may be holding. I also added a new trace event to distinguish operations that caused an error reply from those that were cancelled. One complication is that we only omit sending the message on EINTR errors in order to avoid confusing the rest of the code (which may assume that a client knows about a fid if it sucessfully passed it off to pud_complete without checking for cancellation status). This does mean that if the server acts upon the cancellation flag, it always needs to set err to EINTR. I believe this is true of the current code. [1] https://9fans.github.io/plan9port/man/man9/flush.html [2] https://github.com/torvalds/linux/commit/9523feac272ccad2ad8186ba4fcc891 Signed-off-by: Keno Fischer <keno@juliacomputing.com> Reviewed-by: Greg Kurz <groug@kaod.org> [groug, send a zero-sized reply instead of detaching the buffer] Signed-off-by: Greg Kurz <groug@kaod.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2018-02-019pfs: drop v9fs_register_transport()Greg Kurz
No good reasons to do this outside of v9fs_device_realize_common(). Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2018-01-089pfs: deprecate handle backendGreg Kurz
This backend raise some concerns: - doesn't support symlinks - fails +100 tests in the PJD POSIX file system test suite [1] - requires the QEMU process to run with the CAP_DAC_READ_SEARCH capability, which isn't recommended for security reasons This backend should not be used and wil be removed. The 'local' backend is the recommended alternative. [1] https://www.tuxera.com/community/posix-test-suite/ Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2018-01-08fsdev: improve error handling of backend initGreg Kurz
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>
2018-01-08fsdev: improve error handling of backend opts parsingGreg Kurz
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>
2018-01-089pfs: make pdu_marshal() and pdu_unmarshal() static functionsGreg Kurz
They're only used by the 9p core code. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Eric Blake <eblake@redhat.com>
2018-01-089pfs: fix error path in pdu_submit()Greg Kurz
If we receive an unsupported request id, we first decide to return -ENOTSUPP to the client, but since the request id causes is_read_only_op() to return false, we change the error to be -EROFS if the fsdev is read-only. This doesn't make sense since we don't know what the client asked for. This patch ensures that -EROFS can only be returned if the request id is supported. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Eric Blake <eblake@redhat.com>
2018-01-089pfs: fix type in *_parse_opts declarationsGreg Kurz
To comply with the QEMU coding style. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Eric Blake <eblake@redhat.com>
2018-01-089pfs: handle: fix type definitionGreg Kurz
To comply with the QEMU coding style. Signed-off-by: Greg Kurz <groug@kaod.org>
2018-01-089pfs: fix some type definitionsGreg Kurz
To comply with the QEMU coding style. Signed-off-by: Greg Kurz <groug@kaod.org>
2018-01-089pfs: fix XattrOperations typedefGreg Kurz
To comply with the QEMU coding style. Signed-off-by: Greg Kurz <groug@kaod.org>
2018-01-08virtio-9p: move unrealize/realize after virtio_9p_transport definitionGreg Kurz
And drop the now useless forward declaration of virtio_9p_transport. Signed-off-by: Greg Kurz <groug@kaod.org>
2017-11-069pfs: fix v9fs_mark_fids_unreclaim() return valueGreg Kurz
The return value of v9fs_mark_fids_unreclaim() is then propagated to pdu_complete(). It should be a negative errno, not -1. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Eric Blake <eblake@redhat.com>
2017-11-069pfs: drop one user of struct V9fsFidStateGreg Kurz
To comply with QEMU coding style. Signed-off-by: Greg Kurz <groug@kaod.org>
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-30 19:45:04 +0000