Commit Graph

572 Commits

Author SHA1 Message Date
Christian Schoenebeck
063c75db2e 9pfs: fix qemu_mknodat() to always return -1 on error on macOS host
qemu_mknodat() is expected to behave according to its POSIX API, and
therefore should always return exactly -1 on any error, and errno
should be set for the actual error code.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <c714b5e1cae225ab7575242c45ee0fe4945eb6ad.1651228001.git.qemu_oss@crudebyte.com>
2022-05-01 14:07:03 +02:00
Christian Schoenebeck
9ea3164611 9pfs: fix removing non-existent POSIX ACL xattr on macOS host
When mapped POSIX ACL is used, we are ignoring errors when trying
to remove a POSIX ACL xattr that does not exist. On Linux hosts we
would get ENODATA in such cases, on macOS hosts however we get
ENOATTR instead.

As we can be sure that ENOATTR is defined as being identical on Linux
hosts (at least by qemu/xattr.h), it is safe to fix this issue by
simply comparing against ENOATTR instead of ENODATA.

This patch fixes e.g. a command on Linux guest like:

  cp --preserve=mode old new

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Link: https://lore.kernel.org/qemu-devel/2866993.yOYK24bMf6@silver/
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <34f81e9bffd7a3e65fb7aab5b56c107bd0aac960.1651228001.git.qemu_oss@crudebyte.com>
2022-05-01 14:07:03 +02:00
Christian Schoenebeck
951fe2f89f 9pfs: fix wrong errno being sent to Linux client on macOS host
Linux and macOS only share some errno definitions with equal macro
name and value. In fact most mappings for errno are completely
different on the two systems.

This patch converts some important errno values from macOS host to
corresponding Linux errno values before eventually sending such error
codes along with 'Rlerror' replies (if 9p2000.L is used that is). Not
having translated errnos before violated the 9p2000.L protocol spec,
which says:

  "
  size[4] Rlerror tag[2] ecode[4]

  ... ecode is a numerical Linux errno.
  "

  https://github.com/chaos/diod/wiki/protocol#lerror----return-error-code

This patch fixes a bunch of misbehaviours when running a Linux client
on macOS host. For instance this patch fixes:

  mount -t 9p -o posixacl ...

on Linux guest if security_mode=mapped was used for 9p server, which
refused to mount successfully, because macOS returned ENOATTR==93
when client tried to retrieve POSIX ACL xattrs, because errno 93
is defined as EPROTONOSUPPORT==93 on Linux, so Linux client believed
that xattrs were not supported by filesystem on host in general.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Link: https://lore.kernel.org/qemu-devel/20220421124835.3e664669@bahia/
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <b322ab298a62069e527d2b032028bdc9115afacd.1651228001.git.qemu_oss@crudebyte.com>
2022-05-01 14:07:03 +02:00
Christian Schoenebeck
e5c88e2264 9pfs: fix wrong encoding of rdev field in Rgetattr on macOS
The 'rdev' field in 9p reponse 'Rgetattr' is of type dev_t,
which is actually a system dependant type and therefore both the
size and encoding of dev_t differ between macOS and Linux.

So far we have sent 'rdev' to guest in host's dev_t format as-is,
which caused devices to appear with wrong device numbers on
guests running on macOS hosts, eventually leading to various
misbehaviours on guest in conjunction with device files.

This patch fixes this issue by converting the device number from
host's dev_t format to Linux dev_t format. As 9p request
'Tgettattr' is exclusive to protocol version 9p2000.L, it should
be fair to assume that 'rdev' field is assumed to be in Linux dev_t
format by client as well.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Link: https://lore.kernel.org/qemu-devel/20220421093056.5ab1e7ed@bahia/
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <b3a430c2c382ba69a7405e04c0b090ab0d86f17e.1651228001.git.qemu_oss@crudebyte.com>
2022-05-01 14:07:03 +02:00
Christian Schoenebeck
055ab89327 9pfs: fix qemu_mknodat(S_IFSOCK) on macOS
mknod() on macOS does not support creating sockets, so divert to
call sequence socket(), bind() and fchmodat() respectively if S_IFSOCK
was passed with mode argument.

Link: https://lore.kernel.org/qemu-devel/17933734.zYzKuhC07K@silver/
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <2e7b5ecd7a6d83a538db4e8a22d8fb03e9e0f06e.1651228001.git.qemu_oss@crudebyte.com>
[C.S. - Use AT_SYMLINK_NOFOLLOW instead of AT_SYMLINK_NOFOLLOW_ANY. ]
Link: https://lore.kernel.org/qemu-devel/3704033.BMyLRrx2Jx@silver/
2022-05-01 14:02:08 +02:00
Christian Schoenebeck
096af17127 9pfs: fix qemu_mknodat(S_IFREG) on macOS
mknod() on macOS does not support creating regular files, so
divert to openat_file() if S_IFREG is passed with mode argument.

Furthermore, 'man 2 mknodat' on Linux says: "Zero file type is
equivalent to type S_IFREG".

Link: https://lore.kernel.org/qemu-devel/17933734.zYzKuhC07K@silver/
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Will Cohen <wwcohen@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <3102ca936f88bc1f79d2a325e5bc68f48f54e6e3.1651228000.git.qemu_oss@crudebyte.com>
2022-04-30 13:11:48 +02:00
Christian Schoenebeck
0009df31cb 9pfs: fix inode sequencing in 'synth' driver
The 'synth' driver's root node and the 'synth' driver's first
subdirectory node falsely share the same inode number (zero), which
makes it impossible for 9p clients (i.e. 9p test cases) to distinguish
root node and first subdirectory from each other by comparing their QIDs
(which are derived by 9p server from driver's inode numbers).

Fix this issue by using prefix-increment instead of postfix-increment
operator while generating new inode numbers for subdirectories and files.

Link: https://lore.kernel.org/qemu-devel/3859307.hTDP4D0zbi@silver/
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1nTpyU-0000yR-9o@lizzy.crudebyte.com>
2022-04-30 13:11:47 +02:00
Marc-André Lureau
0f9668e0c1 Remove qemu-common.h include from most units
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-33-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 14:31:55 +02:00
Will Cohen
a136d17590 9p: move P9_XATTR_SIZE_MAX from 9p.h to 9p.c
The patch set adding 9p functionality to darwin introduced an issue
where limits.h, which defines XATTR_SIZE_MAX, is included in 9p.c,
though the referenced constant is needed in 9p.h. This commit fixes that
issue by moving the definition of P9_XATTR_SIZE_MAX, which uses
XATTR_SIZE_MAX, to also be in 9p.c.

Additionally, this commit moves the location of the system headers
include in 9p.c to occur before the project headers (except osdep.h).

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/950
Fixes: 38d7fd68b0 ("9p: darwin: Move XATTR_SIZE_MAX->P9_XATTR_SIZE_MAX")
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220331182651.887-1-wwcohen@gmail.com>
[thuth: Adjusted placement of osdep.h]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-04-01 13:06:07 +02:00
Marc-André Lureau
9edc6313da Replace GCC_FMT_ATTR with G_GNUC_PRINTF
One less qemu-specific macro. It also helps to make some headers/units
only depend on glib, and thus moved in standalone projects eventually.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
2022-03-22 14:40:51 +04:00
Markus Armbruster
1366244ab6 9pfs: Use g_new() & friends where that makes obvious sense
g_new(T, n) is neater than g_malloc(sizeof(T) * n).  It's also safer,
for two reasons.  One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.

This commit only touches allocations with size arguments of the form
sizeof(T).

Initial patch created mechanically with:

    $ spatch --in-place --sp-file scripts/coccinelle/use-g_new-etc.cocci \
	     --macro-file scripts/cocci-macro-file.h FILES...

This uncovers a typing error:

    ../hw/9pfs/9p.c: In function ‘qid_path_fullmap’:
    ../hw/9pfs/9p.c:855:13: error: assignment to ‘QpfEntry *’ from incompatible pointer type ‘QppEntry *’ [-Werror=incompatible-pointer-types]
      855 |         val = g_new0(QppEntry, 1);
	  |             ^

Harmless, because QppEntry is larger than QpfEntry.  Manually fixed to
allocate a QpfEntry instead.

Cc: Greg Kurz <groug@kaod.org>
Cc: Christian Schoenebeck <qemu_oss@crudebyte.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20220315144156.1595462-3-armbru@redhat.com>
2022-03-21 15:44:44 +01:00
Christian Schoenebeck
09d19d5807 9pfs/coth.h: drop Doxygen format on v9fs_co_run_in_worker()
API doc comments in QEMU are supposed to be in kerneldoc format, so
drop Doxygen format used on v9fs_co_run_in_worker() macro.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <a8fdf0290d1e40a68f5577f29aeae12298b70733.1646314856.git.qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Christian Schoenebeck
041b0945f9 9pfs/9p-util.h: convert Doxygen -> kerneldoc format
API doc comments in QEMU are supposed to be in kerneldoc format, so
convert API doc comments from Doxygen format to kerneldoc format.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <dc1c4a85e233f5884ee5f6ec96b87db286083df7.1646314856.git.qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Christian Schoenebeck
e16fea4156 9pfs/9p.c: convert Doxygen -> kerneldoc format
API doc comments in QEMU are supposed to be in kerneldoc format, so
convert API doc comments from Doxygen format to kerneldoc format.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <4ece6ffa4465c271c6a7c42a3040f42780fcce87.1646314856.git.qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Christian Schoenebeck
1a7f240014 9pfs/codir.c: convert Doxygen -> kerneldoc format
API doc comments in QEMU are supposed to be in kerneldoc format, so
convert API doc comments from Doxygen format to kerneldoc format.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <c76be7d38ea448c6417b2ffb5ccd6b711519a878.1646314856.git.qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Christian Schoenebeck
39db334719 9pfs/9p.h: convert Doxygen -> kerneldoc format
API doc comments in QEMU are supposed to be in kerneldoc format, so
convert API doc comments from Doxygen format to kerneldoc format.

Based-on: <E1nPTwO-0006pl-Np@lizzy.crudebyte.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <2b8f91de7bac3d3bc85d60eb08830a35a394be75.1646314856.git.qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Christian Schoenebeck
63ce31c35d 9pfs: drop Doxygen format from qemu_dirent_dup() API comment
API doc comments in QEMU are supposed to be in kerneldoc format, so drop
occurrences of "@c" which is Doxygen format for fixed-width text.

Link: https://lore.kernel.org/qemu-devel/CAFEAcA89+ENOM6x19OEF53Kd2DWkhN5SN21Va0D7yepJSa3Jyg@mail.gmail.com/
Based-on: <E1nP9Oz-00043L-KJ@lizzy.crudebyte.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1nPTwO-0006pl-Np@lizzy.crudebyte.com>
2022-03-07 11:49:31 +01:00
Christian Schoenebeck
1983d8b0d6 9pfs: move qemu_dirent_dup() from osdep -> 9p-util
Function qemu_dirent_dup() is currently only used by 9pfs server, so move
it from project global header osdep.h to 9pfs specific header 9p-util.h.

Link: https://lore.kernel.org/qemu-devel/CAFEAcA_=HAUNomKD2wurSVaAHa5mrk22A1oHKLWUDjk7v6Khmg@mail.gmail.com/
Based-on: <20220227223522.91937-12-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <E1nP9Oz-00043L-KJ@lizzy.crudebyte.com>
2022-03-07 11:49:31 +01:00
Keno Fischer
029ed1bd9d 9p: darwin: Implement compatibility for mknodat
Darwin does not support mknodat. However, to avoid race conditions
with later setting the permissions, we must avoid using mknod on
the full path instead. We could try to fchdir, but that would cause
problems if multiple threads try to call mknodat at the same time.
However, luckily there is a solution: Darwin includes a function
that sets the cwd for the current thread only.
This should suffice to use mknod safely.

This function (pthread_fchdir_np) is protected by a check in
meson in a patch later in this series.

Signed-off-by: Keno Fischer <keno@juliacomputing.com>
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
[Will Cohen: - Adjust coding style
             - Replace clang references with gcc
             - Note radar filed with Apple for missing syscall
             - Replace direct syscall with pthread_fchdir_np and
               adjust patch notes accordingly
             - Declare pthread_fchdir_np with
             - __attribute__((weak_import)) to allow checking for
               its presence before usage
             - Move declarations above cplusplus guard
             - Add CONFIG_PTHREAD_FCHDIR_NP to meson and check for
               presence in 9p-util
             - Rebase to apply cleanly on top of the 2022-02-10
               changes to 9pfs
             - Fix line over 90 characters formatting error]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-10-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Keno Fischer
b5989326f5 9p: darwin: Compatibility for f/l*xattr
On darwin `fgetxattr` takes two extra optional arguments,
and the l* variants are not defined (in favor of an extra
flag to the regular variants.

Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-9-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Acked-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Keno Fischer
57b3910bc3 9p: darwin: *xattr_nofollow implementations
This implements the darwin equivalent of the functions that were
moved to 9p-util(-linux) earlier in this series in the new
9p-util-darwin file.

Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-8-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Acked-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Keno Fischer
38d7fd68b0 9p: darwin: Move XATTR_SIZE_MAX->P9_XATTR_SIZE_MAX
Signed-off-by: Keno Fischer <keno@juliacomputing.com>
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>

Because XATTR_SIZE_MAX is not defined on Darwin,
create a cross-platform P9_XATTR_SIZE_MAX instead.

[Will Cohen: - Adjust coding style
             - Lower XATTR_SIZE_MAX to 64k
             - Add explanatory context related to XATTR_SIZE_MAX]
[Fabian Franz: - Move XATTR_SIZE_MAX reference from 9p.c to
                 P9_XATTR_SIZE_MAX in 9p.h]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Signed-off-by: Fabian Franz <fabianfranz.oss@gmail.com>
[Will Cohen: - For P9_XATTR_MAX, ensure that Linux uses
               XATTR_SIZE_MAX, Darwin uses 64k, and error
               out for undefined hosts]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-7-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Keno Fischer
67a71e3b71 9p: darwin: Ignore O_{NOATIME, DIRECT}
Darwin doesn't have either of these flags. Darwin does have
F_NOCACHE, which is similar to O_DIRECT, but has different
enough semantics that other projects don't generally map
them automatically. In any case, we don't support O_DIRECT
on Linux at the moment either.

Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
[Will Cohen: - Adjust coding style]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-6-wwcohen@gmail.com>
[C.S.: - Fix compiler warning "unused label 'again'". ]
Link: https://lore.kernel.org/qemu-devel/11201492.CjeqJxXfGd@silver/
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Keno Fischer
6b3b279bd6 9p: darwin: Handle struct dirent differences
On darwin d_seekoff exists, but is optional and does not seem to
be commonly used by file systems. Use `telldir` instead to obtain
the seek offset and inject it into d_seekoff, and create a
qemu_dirent_off helper to call it appropriately when appropriate.

Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
[Will Cohen: - Adjust to pass testing
             - Ensure that d_seekoff is filled using telldir
               on darwin, and create qemu_dirent_off helper
               to decide which to access]
[Fabian Franz: - Add telldir error handling for darwin]
Signed-off-by: Fabian Franz <fabianfranz.oss@gmail.com>
[Will Cohen: - Ensure that telldir error handling uses
               signed int
             - Cleanup of telldir error handling
             - Remove superfluous error handling for
               qemu_dirent_off
             - Adjust formatting
             - Use qemu_dirent_off in codir.c
             - Declare qemu_dirent_off as static to prevent
               linker error
             - Move qemu_dirent_off above the end-of-file
               endif to fix compilation]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-5-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-03-07 11:49:31 +01:00
Keno Fischer
f41db099c7 9p: darwin: Handle struct stat(fs) differences
Signed-off-by: Keno Fischer <keno@juliacomputing.com>
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
[Will Cohen: - Note lack of f_namelen and f_frsize on Darwin
             - Ensure that tv_sec and tv_nsec are both
               initialized for Darwin and non-Darwin]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-4-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-03-07 11:49:30 +01:00
Keno Fischer
6450084a66 9p: Rename 9p-util -> 9p-util-linux
The current file only has the Linux versions of these functions.
Rename the file accordingly and update the Makefile to only build
it on Linux. A Darwin version of these will follow later in the
series.

Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220227223522.91937-3-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-03-07 11:49:30 +01:00
Keno Fischer
e0bd743bb2 9p: linux: Fix a couple Linux assumptions
- 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>
2022-03-07 11:49:30 +01:00
Vitaly Chikunov
e64e27d5cb 9pfs: Fix segfault in do_readdir_many caused by struct dirent overread
`struct dirent' returned from readdir(3) could be shorter (or longer)
than `sizeof(struct dirent)', thus memcpy of sizeof length will overread
into unallocated page causing SIGSEGV. Example stack trace:

 #0  0x00005555559ebeed v9fs_co_readdir_many (/usr/bin/qemu-system-x86_64 + 0x497eed)
 #1  0x00005555559ec2e9 v9fs_readdir (/usr/bin/qemu-system-x86_64 + 0x4982e9)
 #2  0x0000555555eb7983 coroutine_trampoline (/usr/bin/qemu-system-x86_64 + 0x963983)
 #3  0x00007ffff73e0be0 n/a (n/a + 0x0)

While fixing this, provide a helper for any future `struct dirent' cloning.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/841
Cc: qemu-stable@nongnu.org
Co-authored-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Tested-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Acked-by: Greg Kurz <groug@kaod.org>
Tested-by: Vitaly Chikunov <vt@altlinux.org>
Message-Id: <20220216181821.3481527-1-vt@altlinux.org>
[C.S. - Fix typo in source comment. ]
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-02-17 16:57:58 +01:00
Christian Schoenebeck
7e985780aa 9pfs: use P9Array in v9fs_walk()
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <90c65d1c1ca11c1b434bb981b1fc7966f7711c8f.1633097129.git.qemu_oss@crudebyte.com>
2021-10-27 14:45:22 +02:00
Christian Schoenebeck
cc82fde9c7 9pfs: make V9fsPath usable via P9Array API
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <79a0ddf8375f6c95f0565ef155a1bf1e9387664f.1633097129.git.qemu_oss@crudebyte.com>
2021-10-27 14:45:22 +02:00
Christian Schoenebeck
04a7f9e55e 9pfs: simplify blksize_to_iounit()
Use QEMU_ALIGN_DOWN() macro to reduce code and to make it
more human readable.

Suggested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <b84eb324d2ebdcc6f9c442c97b5b4d01eecb4f43.1632758315.git.qemu_oss@crudebyte.com>
2021-10-27 14:45:22 +02:00
Christian Schoenebeck
b565bccb00 9pfs: deduplicate iounit code
Remove redundant code that translates host fileystem's block
size into 9p client (guest side) block size.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <129bb71d5119e61d335f1e3107e472e4beea223a.1632758315.git.qemu_oss@crudebyte.com>
2021-10-27 14:45:22 +02:00
Christian Schoenebeck
669ced09b3 9pfs: fix wrong I/O block size in Rgetattr
When client sent a 9p Tgetattr request then the wrong I/O block
size value was returned by 9p server; instead of host file
system's I/O block size it should rather return an I/O block
size according to 9p session's 'msize' value, because the value
returned to client should be an "optimum" block size for I/O
(i.e. to maximize performance), it should not reflect the actual
physical block size of the underlying storage media.

The I/O block size of a host filesystem is typically 4k, so the
value returned was far too low for good 9p I/O performance.

This patch adds stat_to_iounit() with a similar approach as the
existing get_iounit() function.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1mT2Js-0000DW-OH@lizzy.crudebyte.com>
2021-10-27 14:45:22 +02:00
Christian Schoenebeck
f83df00900 9pfs: fix crash in v9fs_walk()
v9fs_walk() utilizes the v9fs_co_run_in_worker({...}) macro to run the
supplied fs driver code block on a background worker thread.

When either the 'Twalk' client request was interrupted or if the client
requested fid for that 'Twalk' request caused a stat error then that
fs driver code block was left by 'break' keyword, with the intention to
return from worker thread back to main thread as well:

    v9fs_co_run_in_worker({
        if (v9fs_request_cancelled(pdu)) {
            err = -EINTR;
            break;
        }
        err = s->ops->lstat(&s->ctx, &dpath, &fidst);
        if (err < 0) {
            err = -errno;
            break;
        }
        ...
    });

However that 'break;' statement also skipped the v9fs_co_run_in_worker()
macro's final and mandatory

    /* re-enter back to qemu thread */
    qemu_coroutine_yield();

call and thus caused the rest of v9fs_walk() to be continued being
executed on the worker thread instead of main thread, eventually
leading to a crash in the transport virtio transport driver.

To fix this issue and to prevent the same error from happening again by
other users of v9fs_co_run_in_worker() in future, auto wrap the supplied
code block into its own

    do { } while (0);

loop inside the 'v9fs_co_run_in_worker' macro definition.

Full discussion and backtrace:
https://lists.gnu.org/archive/html/qemu-devel/2021-08/msg05209.html
https://lists.gnu.org/archive/html/qemu-devel/2021-09/msg00174.html

Fixes: 8d6cb10073
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1mLTBg-0002Bh-2D@lizzy.crudebyte.com>
2021-09-02 13:26:22 +02:00
Christian Schoenebeck
869605b5a0 hw/9pfs: use g_autofree in v9fs_walk() where possible
Suggested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <b51670d2a39399535a035f6bc77c3cbeed85edae.1629208359.git.qemu_oss@crudebyte.com>
2021-09-02 13:26:22 +02:00
Christian Schoenebeck
97b1d8fdf6 hw/9pfs: avoid 'path' copy in v9fs_walk()
The v9fs_walk() function resolves all client submitted path nodes to the
local 'pathes' array. Using a separate string scalar variable 'path'
inside the background worker thread loop and copying that local 'path'
string scalar variable subsequently to the 'pathes' array (at the end of
each loop iteration) is not necessary.

Instead simply resolve each path directly to the 'pathes' array and
don't use the string scalar variable 'path' inside the fs worker thread
loop at all.

The only advantage of the 'path' scalar was that in case of an error
the respective 'pathes' element would not be filled. Right now this is
not an issue as the v9fs_walk() function returns as soon as any error
occurs.

Suggested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <7dacbecf25b2c9b4a0ce12d689a8a535f09a31e3.1629208359.git.qemu_oss@crudebyte.com>
2021-09-02 13:26:22 +02:00
Christian Schoenebeck
8d6cb10073 9pfs: reduce latency of Twalk
As with previous performance optimization on Treaddir handling;
reduce the overall latency, i.e. overall time spent on processing
a Twalk request by reducing the amount of thread hops between the
9p server's main thread and fs worker thread(s).

In fact this patch even reduces the thread hops for Twalk handling
to its theoritical minimum of exactly 2 thread hops:

main thread -> fs worker thread -> main thread

This is achieved by doing all the required fs driver tasks altogether
in a single v9fs_co_run_in_worker({ ... }); code block.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <1a6701674afc4f08d40396e3aa2631e18a4dbb33.1622821729.git.qemu_oss@crudebyte.com>
2021-07-05 13:03:16 +02:00
Christian Schoenebeck
66550339b7 9pfs: drop root_qid
There is no longer a user of root_qid, so drop it.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <6896dd161d3257db6b0513842a14f87ca191fdf6.1622821729.git.qemu_oss@crudebyte.com>
2021-07-05 13:03:16 +02:00
Christian Schoenebeck
f22cad4228 9pfs: replace not_same_qid() by same_stat_id()
As we are actually only comparing the filesystem ID (i.e. device number
and inode number pair) let's use the POSIX stat buffer instead of QIDs,
because resolving QIDs requires to be done on 9p server's main thread
only as it might mutate the server state if inode remapping is enabled.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <26aa465ff9cc9c07e053331554a02fdae3994417.1622821729.git.qemu_oss@crudebyte.com>
2021-07-05 13:03:16 +02:00
Christian Schoenebeck
1d0fc0d0ee 9pfs: drop fid_to_qid()
There is only one user of fid_to_qid() which is v9fs_walk(). Let's
open-code fid_to_qid() directly within v9fs_walk(), because
fid_to_qid() hides the POSIX stat buffer which we are going to need
in the subsequent patch.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <e9a4c9c7a0792ed4db6578d105a0823ea05bc324.1622821729.git.qemu_oss@crudebyte.com>
2021-07-05 13:03:16 +02:00
Christian Schoenebeck
110243750d 9pfs: capture root stat
We already capture the QID of the exported 9p root path, i.e. to
prevent client access outside the defined, exported filesystem's tree.
This is currently checked by comparing the root QID with another FID's
QID.

The problem with the latter is that resolving a QID of any given 9p path
can only be done on 9p server's main thread, that's because it might
mutate the server's state if inode remapping is enabled.

For that reason also capture the POSIX stat info of the root path for
being able to identify on any (e.g. worker) thread whether an
arbitrary given path is identical to the export root.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <eb07d6c2e9925788454cfe33d3802e4ffb23ea9a.1622821729.git.qemu_oss@crudebyte.com>
2021-07-05 13:03:16 +02:00
Christian Schoenebeck
8bf27550ef 9pfs: fix not_same_qid()
There is only one user of not_same_qid() which is v9fs_walk() and the
latter is using it for comparing a client supplied path with the 9p
export root path, for the sole purpose to prevent a Twalk request
from escaping from the exported 9p tree via "..".

However for that specific purpose the implementation of not_same_qid()
is wrong; if mtime of the 9p export root path changed between Tattach
and Twalk then not_same_qid() returns true when actually comparing
against the export root path.

To fix for the actual semantic being used, only compare QID path
members, but do not compare version or type members.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <ca0abae4a899d81c6e87f683732d6c1f56915232.1622821729.git.qemu_oss@crudebyte.com>
2021-07-05 13:03:16 +02:00
Christian Schoenebeck
232a4d2c25 9pfs: simplify v9fs_walk()
There is only one comparison between nwnames and P9_MAXWELEM required.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1liKiz-0006BC-Ja@lizzy.crudebyte.com>
2021-07-05 13:03:16 +02:00
Christian Schoenebeck
6f56908427 9pfs: add link to 9p developer docs
To lower the entry level for new developers, add a link to the 9p
developer docs (i.e. qemu wiki) to MAINTAINERS and to the beginning of
9p source files, that is to: https://wiki.qemu.org/Documentation/9p

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Acked-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1leeDf-0008GZ-9q@lizzy.crudebyte.com>
2021-07-05 13:03:16 +02:00
Stefano Garzarella
d0fb9657a3 docs: fix references to docs/devel/tracing.rst
Commit e50caf4a5c ("tracing: convert documentation to rST")
converted docs/devel/tracing.txt to docs/devel/tracing.rst.

We still have several references to the old file, so let's fix them
with the following command:

  sed -i s/tracing.txt/tracing.rst/ $(git grep -l docs/devel/tracing.txt)

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210517151702.109066-2-sgarzare@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-06-02 06:51:09 +02:00
Mahmoud Mandour
e4fd889f51 hw/9pfs/9p-synth: Replaced qemu_mutex_lock with QEMU_LOCK_GUARD
Replaced a call to qemu_mutex_lock and its respective call to
qemu_mutex_unlock and used QEMU_LOCK_GUARD macro in their place.
This simplifies the code by removing the call required to unlock
and also eliminates goto paths.

Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
Acked-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20210311031538.5325-9-ma.mandourr@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2021-03-16 11:41:49 +01:00
Chen Qun
d6eb39b554 qtest: delete superfluous inclusions of qtest.h
There are 23 files that include the "sysemu/qtest.h",
but they do not use any qtest functions.

Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210226081414.205946-1-kuhn.chenqun@huawei.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-03-09 06:03:53 +01:00
Greg Kurz
81f9766b7a 9pfs: Convert reclaim list to QSLIST
Use QSLIST instead of open-coding for a slightly improved readability.

No behavioral change.

Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20210122143514.215780-1-groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2021-01-22 18:26:40 +01:00
Greg Kurz
20b7f45b22 9pfs: Improve unreclaim loop
If a fid was actually re-opened by v9fs_reopen_fid(), we re-traverse the
fid list from the head in case some other request created a fid that
needs to be marked unreclaimable as well (i.e. the client opened a new
handle on the path that is being unlinked). This is suboptimal since
most if not all fids that require it have likely been taken care of
already.

This is mostly the result of new fids being added to the head of the
list. Since the list is now a QSIMPLEQ, add new fids at the end instead
to avoid the need to rewind. Take a reference on the fid to ensure it
doesn't go away during v9fs_reopen_fid() and that it can be safely
passed to QSIMPLEQ_NEXT() afterwards. Since the associated put_fid()
can also yield, same is done with the next fid. So the logic here is
to get a reference on a fid and only put it back during the next
iteration after we could get a reference on the next fid.

Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20210121181510.1459390-1-groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2021-01-22 15:17:19 +01:00
Greg Kurz
feabd6cf78 9pfs: Convert V9fsFidState::fid_list to QSIMPLEQ
The fid_list is currently open-coded. This doesn't seem to serve any
purpose that cannot be met with QEMU's generic lists. Let's go for a
QSIMPLEQ : this will allow to add new fids at the end of the list and
to improve the logic in v9fs_mark_fids_unreclaim().

Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20210118142300.801516-3-groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2021-01-21 17:49:45 +01:00