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2023-10-20migration: simplify blockersSteve Sistare1-8/+2
Modify migrate_add_blocker and migrate_del_blocker to take an Error ** reason. This allows migration to own the Error object, so that if an error occurs in migrate_add_blocker, migration code can free the Error and clear the client handle, simplifying client code. It also simplifies the migrate_del_blocker call site. In addition, this is a pre-requisite for a proposed future patch that would add a mode argument to migration requests to support live update, and maintain a list of blockers for each mode. A blocker may apply to a single mode or to multiple modes, and passing Error** will allow one Error object to be registered for multiple modes. No functional change. Signed-off-by: Steve Sistare <steven.sistare@oracle.com> Tested-by: Michael Galaxy <mgalaxy@akamai.com> Reviewed-by: Michael Galaxy <mgalaxy@akamai.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Message-ID: <1697634216-84215-1-git-send-email-steven.sistare@oracle.com>
2023-07-25hw/9pfs: spelling fixesMichael Tokarev1-2/+2
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru> Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2023-06-01hw/9pfs: use qemu_xxhash4Alex Bennée1-3/+2
No need to pass zeros as we have helpers that do that for us. Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-id: 20230526165401.574474-11-alex.bennee@linaro.org Message-Id: <20230524133952.3971948-10-alex.bennee@linaro.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-02-08Don't include headers already included by qemu/osdep.hMarkus Armbruster1-2/+0
This commit was created with scripts/clean-includes. Signed-off-by: Markus Armbruster <armbru@redhat.com> Acked-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Message-Id: <20230202133830.2152150-19-armbru@redhat.com>
2022-10-25Merge tag 'trivial-branch-for-7.2-pull-request' of ↵Stefan Hajnoczi1-1/+1
https://gitlab.com/laurent_vivier/qemu into staging Pull request # -----BEGIN PGP SIGNATURE----- # # iQJGBAABCAAwFiEEzS913cjjpNwuT1Fz8ww4vT8vvjwFAmNXleQSHGxhdXJlbnRA # dml2aWVyLmV1AAoJEPMMOL0/L748TIsP/1gulTFpYAs3Kao6IZonsuCzrjQrJWqv # 5SD7cVb7isOWdOSNK3glE4dG54Q38PaS9GHaCvzIndjHxlWddCCUuwiw6p1Wdo70 # fjNfcCOEPoalQbkZvLejhs5n2rlfTvS5JUnLKVD9+ton7hjnTyKGDDYao5mYhtzv # Kn9NpCD3m+K3orzG2Jj7jR1UAumg4cW4YQEpT8ItDT4Y5UAxjL6TZQ6CE220DQDq # YwDrHEgDYr/UKlTbIC/JwlKOLr0sh+UB1VV8GZS6e6pU9u5WpDDHlQZpU8W2tLLg # cG5m8tLG2avFxRMUFrPNZ8Lx2xKO8wL1PtgAO9w7qFK+r0soZvv+Zh4ev/t5zGLf # ciliItqf97yPYNIc3su75jqdQHed7lmZc3m9LBHg8VXN6rAatt8vWUbG90sAZuTU # tWBZHvQmG0s2MK4UYqeQ59tc21v9T2+VCiiv/1vjgEUr8tBhXS562jrDt/bNEqKa # eRzT4h4ffbP6BJRnyakxkFkQ7nd2OdlLNKUAr9Tk6T2fYuarfEdbYx//0950agqD # AAtdQ/AJm6Pq1Px0/RuMKK5WsL818BoAkfr6n7qXleunytJ1W5hjW9EmFIPZWPTR # ce/lSFHA0+MCpg6C8zAa4iNBg/Pk0p3GRrTeWyHK1FjV+Gep1QtE/a1vk/qiPzTM # qZVfPxa8cXXe # =caiq # -----END PGP SIGNATURE----- # gpg: Signature made Tue 25 Oct 2022 03:53:08 EDT # gpg: using RSA key CD2F75DDC8E3A4DC2E4F5173F30C38BD3F2FBE3C # gpg: issuer "laurent@vivier.eu" # gpg: Good signature from "Laurent Vivier <lvivier@redhat.com>" [full] # gpg: aka "Laurent Vivier <laurent@vivier.eu>" [full] # gpg: aka "Laurent Vivier (Red Hat) <lvivier@redhat.com>" [full] # Primary key fingerprint: CD2F 75DD C8E3 A4DC 2E4F 5173 F30C 38BD 3F2F BE3C * tag 'trivial-branch-for-7.2-pull-request' of https://gitlab.com/laurent_vivier/qemu: accel/tcg/tcg-accel-ops-rr: fix trivial typo ui: remove useless typecasts treewide: Remove the unnecessary space before semicolon include/hw/scsi/scsi.h: Remove unused scsi_legacy_handle_cmdline() prototype vmstate-static-checker:remove this redundant return tests/qtest: vhost-user-test: Fix [-Werror=format-overflow=] build warning tests/qtest: migration-test: Fix [-Werror=format-overflow=] build warning Drop useless casts from g_malloc() & friends to pointer elf2dmp: free memory in failure hw/core: Tidy up unnecessary casting away of const .gitignore: add multiple items to .gitignore Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-10-24treewide: Remove the unnecessary space before semicolonBin Meng1-1/+1
%s/return ;/return; Signed-off-by: Bin Meng <bmeng@tinylab.org> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Message-Id: <20221024072802.457832-1-bmeng@tinylab.org> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-10-249pfs: use GHashTable for fid tableLinus Heckemann1-83/+111
The previous implementation would iterate over the fid table for lookup operations, resulting in an operation with O(n) complexity on the number of open files and poor cache locality -- for every open, stat, read, write, etc operation. This change uses a hashtable for this instead, significantly improving the performance of the 9p filesystem. The runtime of NixOS's simple installer test, which copies ~122k files totalling ~1.8GiB from 9p, decreased by a factor of about 10. Signed-off-by: Linus Heckemann <git@sphalerite.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Greg Kurz <groug@kaod.org> [CS: - Retain BUG_ON(f->clunked) in get_fid(). - Add TODO comment in clunk_fid(). ] Message-Id: <20221004104121.713689-1-git@sphalerite.org> [CS: - Drop unnecessary goto and out: label. ] Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2022-06-169pfs: fix 'Twalk' to only send error if no component walkedChristian Schoenebeck1-16/+33
Current implementation of 'Twalk' request handling always sends an 'Rerror' response if any error occured. The 9p2000 protocol spec says though: " If the first element cannot be walked for any reason, Rerror is returned. Otherwise, the walk will return an Rwalk message containing nwqid qids corresponding, in order, to the files that are visited by the nwqid successful elementwise walks; nwqid is therefore either nwname or the index of the first elementwise walk that failed. " http://ericvh.github.io/9p-rfc/rfc9p2000.html#anchor33 For that reason we are no longer leaving from an error path in function v9fs_walk(), unless really no path component could be walked successfully or if the request has been interrupted. Local variable 'nwalked' counts and reflects the number of path components successfully processed by background I/O thread, whereas local variable 'name_idx' subsequently counts and reflects the number of path components eventually accepted successfully by 9p server controller portion. New local variable 'any_err' is an aggregate variable reflecting whether any error occurred at all, while already existing variable 'err' only reflects the last error. Despite QIDs being delivered to client in a more relaxed way now, it is important to note though that fid still must remain unaffected if any error occurred. Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Reviewed-by: Greg Kurz <groug@kaod.org> Message-Id: <bc73e24258a75dc29458024c7936c8a036c3eac5.1647339025.git.qemu_oss@crudebyte.com>
2022-06-169pfs: refactor 'name_idx' -> 'nwalked' in v9fs_walk()Christian Schoenebeck1-8/+8
The local variable 'name_idx' is used in two loops in function v9fs_walk(). Let the first loop use its own variable 'nwalked' instead, which we will use in subsequent patch as the number of (requested) path components successfully walked by background I/O thread. Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Reviewed-by: Greg Kurz <groug@kaod.org> Message-Id: <d506308e7e343023c4db95d0e6053dd2627ed3c1.1647339025.git.qemu_oss@crudebyte.com>
2022-05-019pfs: fix wrong errno being sent to Linux client on macOS hostChristian Schoenebeck1-0/+2
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>
2022-05-019pfs: fix wrong encoding of rdev field in Rgetattr on macOSChristian Schoenebeck1-1/+1
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>
2022-04-019p: move P9_XATTR_SIZE_MAX from 9p.h to 9p.cWill Cohen1-5/+23
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>
2022-03-22Replace GCC_FMT_ATTR with G_GNUC_PRINTFMarc-André Lureau1-1/+1
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>
2022-03-219pfs: Use g_new() & friends where that makes obvious senseMarkus Armbruster1-4/+4
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>
2022-03-079pfs/9p.c: convert Doxygen -> kerneldoc formatChristian Schoenebeck1-27/+35
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>
2022-03-079p: darwin: Move XATTR_SIZE_MAX->P9_XATTR_SIZE_MAXKeno Fischer1-1/+1
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>
2022-03-079p: darwin: Ignore O_{NOATIME, DIRECT}Keno Fischer1-1/+12
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>
2022-03-079p: darwin: Handle struct dirent differencesKeno Fischer1-2/+5
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>
2022-03-079p: darwin: Handle struct stat(fs) differencesKeno Fischer1-2/+14
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>
2022-03-079p: linux: Fix a couple Linux assumptionsKeno Fischer1-0/+4
- 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>
2021-10-279pfs: use P9Array in v9fs_walk()Christian Schoenebeck1-12/+5
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Message-Id: <90c65d1c1ca11c1b434bb981b1fc7966f7711c8f.1633097129.git.qemu_oss@crudebyte.com>
2021-10-279pfs: make V9fsPath usable via P9Array APIChristian Schoenebeck1-0/+2
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Message-Id: <79a0ddf8375f6c95f0565ef155a1bf1e9387664f.1633097129.git.qemu_oss@crudebyte.com>
2021-10-279pfs: simplify blksize_to_iounit()Christian Schoenebeck1-2/+1
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>
2021-10-279pfs: deduplicate iounit codeChristian Schoenebeck1-21/+20
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>
2021-10-279pfs: fix wrong I/O block size in RgetattrChristian Schoenebeck1-1/+20
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>
2021-09-02hw/9pfs: use g_autofree in v9fs_walk() where possibleChristian Schoenebeck1-4/+3
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>
2021-09-02hw/9pfs: avoid 'path' copy in v9fs_walk()Christian Schoenebeck1-4/+4
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>
2021-07-059pfs: reduce latency of TwalkChristian Schoenebeck1-19/+70
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>
2021-07-059pfs: drop root_qidChristian Schoenebeck1-1/+0
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>
2021-07-059pfs: replace not_same_qid() by same_stat_id()Christian Schoenebeck1-3/+3
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>
2021-07-059pfs: drop fid_to_qid()Christian Schoenebeck1-18/+5
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>
2021-07-059pfs: capture root statChristian Schoenebeck1-1/+9
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>
2021-07-059pfs: fix not_same_qid()Christian Schoenebeck1-4/+1
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>
2021-07-059pfs: simplify v9fs_walk()Christian Schoenebeck1-4/+5
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>
2021-07-059pfs: add link to 9p developer docsChristian Schoenebeck1-0/+5
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>
2021-03-09qtest: delete superfluous inclusions of qtest.hChen Qun1-1/+0
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>
2021-01-229pfs: Convert reclaim list to QSLISTGreg Kurz1-9/+8
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>
2021-01-229pfs: Improve unreclaim loopGreg Kurz1-14/+32
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>
2021-01-219pfs: Convert V9fsFidState::fid_list to QSIMPLEQGreg Kurz1-23/+18
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>
2021-01-219pfs: Convert V9fsFidState::clunked to boolGreg Kurz1-2/+2
This can only be 0 or 1. Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Message-Id: <20210118142300.801516-2-groug@kaod.org> Signed-off-by: Greg Kurz <groug@kaod.org>
2021-01-159pfs: Fully restart unreclaim loop (CVE-2021-20181)Greg Kurz1-3/+3
Depending on the client activity, the server can be asked to open a huge number of file descriptors and eventually hit RLIMIT_NOFILE. This is currently mitigated using a reclaim logic : the server closes the file descriptors of idle fids, based on the assumption that it will be able to re-open them later. This assumption doesn't hold of course if the client requests the file to be unlinked. In this case, we loop on the entire fid list and mark all related fids as unreclaimable (the reclaim logic will just ignore them) and, of course, we open or re-open their file descriptors if needed since we're about to unlink the file. This is the purpose of v9fs_mark_fids_unreclaim(). Since the actual opening of a file can cause the coroutine to yield, another client request could possibly add a new fid that we may want to mark as non-reclaimable as well. The loop is thus restarted if the re-open request was actually transmitted to the backend. This is achieved by keeping a reference on the first fid (head) before traversing the list. This is wrong in several ways: - a potential clunk request from the client could tear the first fid down and cause the reference to be stale. This leads to a use-after-free error that can be detected with ASAN, using a custom 9p client - fids are added at the head of the list : restarting from the previous head will always miss fids added by a some other potential request All these problems could be avoided if fids were being added at the end of the list. This can be achieved with a QSIMPLEQ, but this is probably too much change for a bug fix. For now let's keep it simple and just restart the loop from the current head. Fixes: CVE-2021-20181 Buglink: https://bugs.launchpad.net/qemu/+bug/1911666 Reported-by: Zero Day Initiative <zdi-disclosures@trendmicro.com> Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Message-Id: <161064025265.1838153.15185571283519390907.stgit@bahia.lan> Signed-off-by: Greg Kurz <groug@kaod.org>
2020-11-05hw/9pfs : add spaces around operatorXinhao Zhang1-8/+8
Fix code style. Operator needs spaces both sides. Signed-off-by: Xinhao Zhang <zhangxinhao1@huawei.com> Signed-off-by: Kai Deng <dengkai1@huawei.com> Reported-by: Euler Robot <euler.robot@huawei.com> Reviewed-by: Greg Kurz <groug@kaod.org> Message-Id: <20201030043515.1030223-1-zhangxinhao1@huawei.com> Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2020-09-159pfs: disable msize warning for synth driverChristian Schoenebeck1-1/+1
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>
2020-09-159pfs: log warning if msize <= 8192Christian Schoenebeck1-0/+9
It is essential to choose a reasonable high value for 'msize' to avoid severely degraded file I/O performance. This parameter can only be chosen on client/guest side, and a Linux client defaults to an 'msize' of only 8192 if the user did not explicitly specify a value for 'msize', which results in very poor file I/O performance. Unfortunately many users are not aware that they should specify an appropriate value for 'msize' to avoid severe performance issues, so log a performance warning (with a QEMU wiki link explaining this issue in detail) on host side in that case to make it more clear. Currently a client cannot automatically pick a reasonable value for 'msize', because a good value for 'msize' depends on the file I/O potential of the underlying storage on host side, i.e. a feature invisible to the client, and even then a user would still need to trade off between performance profit and additional RAM costs, i.e. with growing 'msize' (RAM occupation), performance still increases, but performance delta will shrink continuously. Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Reviewed-by: Greg Kurz <groug@kaod.org> Message-Id: <e6fc84845c95816ad5baecb0abd6bfefdcf7ec9f.1599144062.git.qemu_oss@crudebyte.com> Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2020-08-129pfs: differentiate readdir lock between 9P2000.u vs. 9P2000.LChristian Schoenebeck1-3/+18
Previous patch suggests that it might make sense to use a different mutex type now while handling readdir requests, depending on the precise protocol variant, as v9fs_do_readdir_with_stat() (used by 9P2000.u) uses a CoMutex to avoid deadlocks that might happen with QemuMutex otherwise, whereas do_readdir_many() (used by 9P2000.L) should better use a QemuMutex, as the precise behaviour of a failed CoMutex lock on fs driver side would not be clear. And to avoid the wrong lock type being used, be now strict and error out if a 9P2000.L client sends a Tread on a directory, and likeweise error out if a 9P2000.u client sends a Treaddir request. This patch is just intended as transitional measure, as currently 9P2000.u vs. 9P2000.L implementations currently differ where the main logic of fetching directory entries is located at (9P2000.u still being more top half focused, while 9P2000.L already being bottom half focused in regards to fetching directory entries that is). Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Message-Id: <9a2ddc347e533b0d801866afd9dfac853d2d4106.1596012787.git.qemu_oss@crudebyte.com> Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2020-08-129pfs: T_readdir latency optimizationChristian Schoenebeck1-74/+58
Make top half really top half and bottom half really bottom half: Each T_readdir request handling is hopping between threads (main I/O thread and background I/O driver threads) several times for every individual directory entry, which sums up to huge latencies for handling just a single T_readdir request. Instead of doing that, collect now all required directory entries (including all potentially required stat buffers for each entry) in one rush on a background I/O thread from fs driver by calling the previously added function v9fs_co_readdir_many() instead of v9fs_co_readdir(), then assemble the entire resulting network response message for the readdir request on main I/O thread. The fs driver is still aborting the directory entry retrieval loop (on the background I/O thread inside of v9fs_co_readdir_many()) as soon as it would exceed the client's requested maximum R_readdir response size. So this will not introduce a performance penalty on another end. Also: No longer seek initial directory position in v9fs_readdir(), as this is now handled (more consistently) by v9fs_co_readdir_many() instead. Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Message-Id: <c7c3d1cf4e86611538cef44897842819d9359d7a.1596012787.git.qemu_oss@crudebyte.com> Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2020-08-129pfs: make v9fs_readdir_response_size() publicChristian Schoenebeck1-2/+8
Rename function v9fs_readdir_data_size() -> v9fs_readdir_response_size() and make it callable from other units. So far this function is only used by 9p.c, however subsequent patches require the function to be callable from another 9pfs unit. And as we're at it; also make it clear for what this function is used for. Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Reviewed-by: Greg Kurz <groug@kaod.org> Message-Id: <3668ebc7d5b929a0e4f1357457060d96f50f76f4.1596012787.git.qemu_oss@crudebyte.com> Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
2020-07-10virtio-9p: Use ERRP_GUARD()Vladimir Sementsov-Ogievskiy1-0/+1
If we want to check error after errp-function call, we need to introduce local_err and then propagate it to errp. Instead, use the ERRP_GUARD() macro, benefits are: 1. No need of explicit error_propagate call 2. No need of explicit local_err variable: use errp directly 3. ERRP_GUARD() leaves errp as is if it's not NULL or &error_fatal, this means that we don't break error_abort (we'll abort on error_set, not on error_propagate) If we want to add some info to errp (by error_prepend() or error_append_hint()), we must use the ERRP_GUARD() macro. Otherwise, this info will not be added when errp == &error_fatal (the program will exit prior to the error_append_hint() or error_prepend() call). Fix such a case in v9fs_device_realize_common(). This commit is generated by command sed -n '/^virtio-9p$/,/^$/{s/^F: //p}' MAINTAINERS | \ xargs git ls-files | grep '\.[hc]$' | \ xargs spatch \ --sp-file scripts/coccinelle/errp-guard.cocci \ --macro-file scripts/cocci-macro-file.h \ --in-place --no-show-diff --max-width 80 Reported-by: Kevin Wolf <kwolf@redhat.com> Reported-by: Greg Kurz <groug@kaod.org> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Acked-by: Greg Kurz <groug@kaod.org> Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com> [Commit message tweaked] Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20200707165037.1026246-7-armbru@redhat.com> [ERRP_AUTO_PROPAGATE() renamed to ERRP_GUARD(), and auto-propagated-errp.cocci to errp-guard.cocci. Commit message tweaked again.]
2020-07-02Clean up some calls to ignore Error objects the right wayMarkus Armbruster1-4/+2
Receiving the error in a local variable only to free it is less clear (and also less efficient) than passing NULL. Clean up. Cc: Daniel P. Berrange <berrange@redhat.com> Cc: Jerome Forissier <jerome@forissier.org> CC: Greg Kurz <groug@kaod.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Greg Kurz <groug@kaod.org> Message-Id: <20200630090351.1247703-4-armbru@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2020-05-25Revert "9p: init_in_iov_from_pdu can truncate the size"Stefano Stabellini1-22/+11
This reverts commit 16724a173049ac29c7b5ade741da93a0f46edff7. It causes https://bugs.launchpad.net/bugs/1877688. Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com> Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Message-Id: <20200521192627.15259-1-sstabellini@kernel.org> Signed-off-by: Greg Kurz <groug@kaod.org>
generated by cgit v1.1 at 2024-10-20 09:34:04 +0000