[PULL 0/4] 9p patches 2019-10-08

[PULL 0/4] 9p patches 2019-10-08

[Greg Kurz]

The following changes since commit 0f0b43868a566068fc137632fd51bd3cbb23f350:

  Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-4.2-20191004' into staging (2019-10-07 13:49:02 +0100)

are available in the Git repository at:

  https://github.com/gkurz/qemu.git tags/9p-next-2019-10-08

for you to fetch changes up to bc6c3cbf43dcc55e34e05bfcbd302bf1a4b92af7:

  9p: Treat multiple devices on one export as an error (2019-10-08 11:50:11 +0200)

----------------------------------------------------------------
The most notable change is to detect cross-device setups and warn the
user that this may result in inode number collisions and chaos in the
guest. The rest is cosmetic cleanup.

----------------------------------------------------------------
Antonios Motakis (2):
      9p: unsigned type for type, version, path
      9p: Treat multiple devices on one export as an error

Greg Kurz (2):
      9p: Simplify error path of v9fs_device_realize_common()
      fsdev: Add return value to fsdev_throttle_parse_opts()

 fsdev/9p-marshal.h          |  6 +--
 fsdev/qemu-fsdev-throttle.c |  4 +-
 fsdev/qemu-fsdev-throttle.h |  2 +-
 hw/9pfs/9p-local.c          |  7 +++-
 hw/9pfs/9p-proxy.c          |  4 ++
 hw/9pfs/9p.c                | 92 ++++++++++++++++++++++++++++++++-------------
 hw/9pfs/9p.h                |  1 +
 hw/9pfs/trace-events        | 14 +++----
 8 files changed, 88 insertions(+), 42 deletions(-)
-- 
2.21.0

[PULL 1/4] 9p: unsigned type for type, version, path

[Greg Kurz]

From: Antonios Motakis <antonios.motakis@huawei.com>

There is no need for signedness on these QID fields for 9p.

Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com>
[CS: - Also make QID type unsigned.
     - Adjust donttouch_stat() to new types.
     - Adjust trace-events to new types. ]
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
---
 fsdev/9p-marshal.h   |  6 +++---
 hw/9pfs/9p.c         |  6 +++---
 hw/9pfs/trace-events | 14 +++++++-------
 3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/fsdev/9p-marshal.h b/fsdev/9p-marshal.h
index c8823d878f98..8f3babb60a05 100644
--- a/fsdev/9p-marshal.h
+++ b/fsdev/9p-marshal.h
@@ -9,9 +9,9 @@ typedef struct V9fsString
 
 typedef struct V9fsQID
 {
-    int8_t type;
-    int32_t version;
-    int64_t path;
+    uint8_t type;
+    uint32_t version;
+    uint64_t path;
 } V9fsQID;
 
 typedef struct V9fsStat
diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index cce2366219be..cf317bdd2b92 100644
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -744,9 +744,9 @@ static int donttouch_stat(V9fsStat *stat)
 {
     if (stat->type == -1 &&
         stat->dev == -1 &&
-        stat->qid.type == -1 &&
-        stat->qid.version == -1 &&
-        stat->qid.path == -1 &&
+        stat->qid.type == 0xff &&
+        stat->qid.version == (uint32_t) -1 &&
+        stat->qid.path == (uint64_t) -1 &&
         stat->mode == -1 &&
         stat->atime == -1 &&
         stat->mtime == -1 &&
diff --git a/hw/9pfs/trace-events b/hw/9pfs/trace-events
index c0a0a4ab5de8..10188daf7fa5 100644
--- a/hw/9pfs/trace-events
+++ b/hw/9pfs/trace-events
@@ -6,7 +6,7 @@ v9fs_rerror(uint16_t tag, uint8_t id, int err) "tag %d id %d err %d"
 v9fs_version(uint16_t tag, uint8_t id, int32_t msize, char* version) "tag %d id %d msize %d version %s"
 v9fs_version_return(uint16_t tag, uint8_t id, int32_t msize, char* version) "tag %d id %d msize %d version %s"
 v9fs_attach(uint16_t tag, uint8_t id, int32_t fid, int32_t afid, char* uname, char* aname) "tag %u id %u fid %d afid %d uname %s aname %s"
-v9fs_attach_return(uint16_t tag, uint8_t id, int8_t type, int32_t version, int64_t path) "tag %d id %d type %d version %d path %"PRId64
+v9fs_attach_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path) "tag %u id %u type %u version %u path %"PRIu64
 v9fs_stat(uint16_t tag, uint8_t id, int32_t fid) "tag %d id %d fid %d"
 v9fs_stat_return(uint16_t tag, uint8_t id, int32_t mode, int32_t atime, int32_t mtime, int64_t length) "tag %d id %d stat={mode %d atime %d mtime %d length %"PRId64"}"
 v9fs_getattr(uint16_t tag, uint8_t id, int32_t fid, uint64_t request_mask) "tag %d id %d fid %d request_mask %"PRIu64
@@ -14,9 +14,9 @@ v9fs_getattr_return(uint16_t tag, uint8_t id, uint64_t result_mask, uint32_t mod
 v9fs_walk(uint16_t tag, uint8_t id, int32_t fid, int32_t newfid, uint16_t nwnames) "tag %d id %d fid %d newfid %d nwnames %d"
 v9fs_walk_return(uint16_t tag, uint8_t id, uint16_t nwnames, void* qids) "tag %d id %d nwnames %d qids %p"
 v9fs_open(uint16_t tag, uint8_t id, int32_t fid, int32_t mode) "tag %d id %d fid %d mode %d"
-v9fs_open_return(uint16_t tag, uint8_t id, int8_t type, int32_t version, int64_t path, int iounit) "tag %d id %d qid={type %d version %d path %"PRId64"} iounit %d"
+v9fs_open_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path, int iounit) "tag %u id %u qid={type %u version %u path %"PRIu64"} iounit %d"
 v9fs_lcreate(uint16_t tag, uint8_t id, int32_t dfid, int32_t flags, int32_t mode, uint32_t gid) "tag %d id %d dfid %d flags %d mode %d gid %u"
-v9fs_lcreate_return(uint16_t tag, uint8_t id, int8_t type, int32_t version, int64_t path, int32_t iounit) "tag %d id %d qid={type %d version %d path %"PRId64"} iounit %d"
+v9fs_lcreate_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path, int32_t iounit) "tag %u id %u qid={type %u version %u path %"PRIu64"} iounit %d"
 v9fs_fsync(uint16_t tag, uint8_t id, int32_t fid, int datasync) "tag %d id %d fid %d datasync %d"
 v9fs_clunk(uint16_t tag, uint8_t id, int32_t fid) "tag %d id %d fid %d"
 v9fs_read(uint16_t tag, uint8_t id, int32_t fid, uint64_t off, uint32_t max_count) "tag %d id %d fid %d off %"PRIu64" max_count %u"
@@ -26,21 +26,21 @@ v9fs_readdir_return(uint16_t tag, uint8_t id, uint32_t count, ssize_t retval) "t
 v9fs_write(uint16_t tag, uint8_t id, int32_t fid, uint64_t off, uint32_t count, int cnt) "tag %d id %d fid %d off %"PRIu64" count %u cnt %d"
 v9fs_write_return(uint16_t tag, uint8_t id, int32_t total, ssize_t err) "tag %d id %d total %d err %zd"
 v9fs_create(uint16_t tag, uint8_t id, int32_t fid, char* name, int32_t perm, int8_t mode) "tag %d id %d fid %d name %s perm %d mode %d"
-v9fs_create_return(uint16_t tag, uint8_t id, int8_t type, int32_t version, int64_t path, int iounit) "tag %d id %d qid={type %d version %d path %"PRId64"} iounit %d"
+v9fs_create_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path, int iounit) "tag %u id %u qid={type %u version %u path %"PRIu64"} iounit %d"
 v9fs_symlink(uint16_t tag, uint8_t id, int32_t fid,  char* name, char* symname, uint32_t gid) "tag %d id %d fid %d name %s symname %s gid %u"
-v9fs_symlink_return(uint16_t tag, uint8_t id, int8_t type, int32_t version, int64_t path) "tag %d id %d qid={type %d version %d path %"PRId64"}"
+v9fs_symlink_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path) "tag %u id %u qid={type %u version %u path %"PRIu64"}"
 v9fs_flush(uint16_t tag, uint8_t id, int16_t flush_tag) "tag %d id %d flush_tag %d"
 v9fs_link(uint16_t tag, uint8_t id, int32_t dfid, int32_t oldfid, char* name) "tag %d id %d dfid %d oldfid %d name %s"
 v9fs_remove(uint16_t tag, uint8_t id, int32_t fid) "tag %d id %d fid %d"
 v9fs_wstat(uint16_t tag, uint8_t id, int32_t fid, int32_t mode, int32_t atime, int32_t mtime) "tag %u id %u fid %d stat={mode %d atime %d mtime %d}"
 v9fs_mknod(uint16_t tag, uint8_t id, int32_t fid, int mode, int major, int minor) "tag %d id %d fid %d mode %d major %d minor %d"
-v9fs_mknod_return(uint16_t tag, uint8_t id, int8_t type, int32_t version, int64_t path) "tag %d id %d qid={type %d version %d path %"PRId64"}"
+v9fs_mknod_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path) "tag %u id %u qid={type %u version %u path %"PRIu64"}"
 v9fs_lock(uint16_t tag, uint8_t id, int32_t fid, uint8_t type, uint64_t start, uint64_t length) "tag %d id %d fid %d type %d start %"PRIu64" length %"PRIu64
 v9fs_lock_return(uint16_t tag, uint8_t id, int8_t status) "tag %d id %d status %d"
 v9fs_getlock(uint16_t tag, uint8_t id, int32_t fid, uint8_t type, uint64_t start, uint64_t length)"tag %d id %d fid %d type %d start %"PRIu64" length %"PRIu64
 v9fs_getlock_return(uint16_t tag, uint8_t id, uint8_t type, uint64_t start, uint64_t length, uint32_t proc_id) "tag %d id %d type %d start %"PRIu64" length %"PRIu64" proc_id %u"
 v9fs_mkdir(uint16_t tag, uint8_t id, int32_t fid, char* name, int mode, uint32_t gid) "tag %u id %u fid %d name %s mode %d gid %u"
-v9fs_mkdir_return(uint16_t tag, uint8_t id, int8_t type, int32_t version, int64_t path, int err) "tag %u id %u qid={type %d version %d path %"PRId64"} err %d"
+v9fs_mkdir_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path, int err) "tag %u id %u qid={type %u version %u path %"PRIu64"} err %d"
 v9fs_xattrwalk(uint16_t tag, uint8_t id, int32_t fid, int32_t newfid, char* name) "tag %d id %d fid %d newfid %d name %s"
 v9fs_xattrwalk_return(uint16_t tag, uint8_t id, int64_t size) "tag %d id %d size %"PRId64
 v9fs_xattrcreate(uint16_t tag, uint8_t id, int32_t fid, char* name, uint64_t size, int flags) "tag %d id %d fid %d name %s size %"PRIu64" flags %d"
-- 
2.21.0

[PULL 2/4] 9p: Simplify error path of v9fs_device_realize_common()

[Greg Kurz]

Make v9fs_device_unrealize_common() idempotent and use it for rollback,
in order to reduce code duplication.

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 hw/9pfs/9p-local.c |  4 ++++
 hw/9pfs/9p-proxy.c |  4 ++++
 hw/9pfs/9p.c       | 16 ++++++----------
 3 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c
index 08e673a79c22..6f7309f4e691 100644
--- a/hw/9pfs/9p-local.c
+++ b/hw/9pfs/9p-local.c
@@ -1465,6 +1465,10 @@ static void local_cleanup(FsContext *ctx)
 {
     LocalData *data = ctx->private;
 
+    if (!data) {
+        return;
+    }
+
     close(data->mountfd);
     g_free(data);
 }
diff --git a/hw/9pfs/9p-proxy.c b/hw/9pfs/9p-proxy.c
index 57a8c1c80886..97ab9c58a573 100644
--- a/hw/9pfs/9p-proxy.c
+++ b/hw/9pfs/9p-proxy.c
@@ -1185,6 +1185,10 @@ static void proxy_cleanup(FsContext *ctx)
 {
     V9fsProxy *proxy = ctx->private;
 
+    if (!proxy) {
+        return;
+    }
+
     g_free(proxy->out_iovec.iov_base);
     g_free(proxy->in_iovec.iov_base);
     if (ctx->export_flags & V9FS_PROXY_SOCK_NAME) {
diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index cf317bdd2b92..ba1ab920f1eb 100644
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -3637,27 +3637,23 @@ int v9fs_device_realize_common(V9fsState *s, const V9fsTransport *t,
     s->ctx.fst = &fse->fst;
     fsdev_throttle_init(s->ctx.fst);
 
-    v9fs_path_free(&path);
-
     rc = 0;
 out:
     if (rc) {
-        if (s->ops && s->ops->cleanup && s->ctx.private) {
-            s->ops->cleanup(&s->ctx);
-        }
-        g_free(s->tag);
-        g_free(s->ctx.fs_root);
-        v9fs_path_free(&path);
+        v9fs_device_unrealize_common(s, NULL);
     }
+    v9fs_path_free(&path);
     return rc;
 }
 
 void v9fs_device_unrealize_common(V9fsState *s, Error **errp)
 {
-    if (s->ops->cleanup) {
+    if (s->ops && s->ops->cleanup) {
         s->ops->cleanup(&s->ctx);
     }
-    fsdev_throttle_cleanup(s->ctx.fst);
+    if (s->ctx.fst) {
+        fsdev_throttle_cleanup(s->ctx.fst);
+    }
     g_free(s->tag);
     g_free(s->ctx.fs_root);
 }
-- 
2.21.0

[PULL 3/4] fsdev: Add return value to fsdev_throttle_parse_opts()

[Greg Kurz]

It is more convenient to use the return value of the function to notify
errors, rather than to be tied up setting up the &local_err boilerplate.

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 fsdev/qemu-fsdev-throttle.c | 4 ++--
 fsdev/qemu-fsdev-throttle.h | 2 +-
 hw/9pfs/9p-local.c          | 3 +--
 3 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/fsdev/qemu-fsdev-throttle.c b/fsdev/qemu-fsdev-throttle.c
index fe1d76dc76e7..5c83a1cc09c3 100644
--- a/fsdev/qemu-fsdev-throttle.c
+++ b/fsdev/qemu-fsdev-throttle.c
@@ -31,7 +31,7 @@ static void fsdev_throttle_write_timer_cb(void *opaque)
     qemu_co_enter_next(&fst->throttled_reqs[true], NULL);
 }
 
-void fsdev_throttle_parse_opts(QemuOpts *opts, FsThrottle *fst, Error **errp)
+int fsdev_throttle_parse_opts(QemuOpts *opts, FsThrottle *fst, Error **errp)
 {
     throttle_config_init(&fst->cfg);
     fst->cfg.buckets[THROTTLE_BPS_TOTAL].avg =
@@ -75,7 +75,7 @@ void fsdev_throttle_parse_opts(QemuOpts *opts, FsThrottle *fst, Error **errp)
     fst->cfg.op_size =
         qemu_opt_get_number(opts, "throttling.iops-size", 0);
 
-    throttle_is_valid(&fst->cfg, errp);
+    return throttle_is_valid(&fst->cfg, errp) ? 0 : -1;
 }
 
 void fsdev_throttle_init(FsThrottle *fst)
diff --git a/fsdev/qemu-fsdev-throttle.h b/fsdev/qemu-fsdev-throttle.h
index c98e2feab553..a21aecddc734 100644
--- a/fsdev/qemu-fsdev-throttle.h
+++ b/fsdev/qemu-fsdev-throttle.h
@@ -26,7 +26,7 @@ typedef struct FsThrottle {
     CoQueue      throttled_reqs[2];
 } FsThrottle;
 
-void fsdev_throttle_parse_opts(QemuOpts *, FsThrottle *, Error **);
+int fsdev_throttle_parse_opts(QemuOpts *, FsThrottle *, Error **);
 
 void fsdev_throttle_init(FsThrottle *);
 
diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c
index 6f7309f4e691..5c7f4cd9c7b0 100644
--- a/hw/9pfs/9p-local.c
+++ b/hw/9pfs/9p-local.c
@@ -1511,8 +1511,7 @@ static int local_parse_opts(QemuOpts *opts, FsDriverEntry *fse, Error **errp)
         return -1;
     }
 
-    fsdev_throttle_parse_opts(opts, &fse->fst, &local_err);
-    if (local_err) {
+    if (fsdev_throttle_parse_opts(opts, &fse->fst, &local_err)) {
         error_propagate_prepend(errp, local_err,
                                 "invalid throttle configuration: ");
         return -1;
-- 
2.21.0

[PULL 4/4] 9p: Treat multiple devices on one export as an error

[Greg Kurz]

From: Antonios Motakis <antonios.motakis@huawei.com>

The QID path should uniquely identify a file. However, the
inode of a file is currently used as the QID path, which
on its own only uniquely identifies files within a device.
Here we track the device hosting the 9pfs share, in order
to prevent security issues with QID path collisions from
other devices.

We only print a warning for now but a subsequent patch will
allow users to have finer control over the desired behaviour.
Failing the I/O will be one the proposed behaviour, so we
also change stat_to_qid() to return an error here in order to
keep other patches simpler.

Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com>
[CS: - Assign dev_id to export root's device already in
       v9fs_device_realize_common(), not postponed in
       stat_to_qid().
     - error_report_once() if more than one device was
       shared by export.
     - Return -ENODEV instead of -ENOSYS in stat_to_qid().
     - Fixed typo in log comment. ]
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
[groug, changed to warning, updated message and changelog]
Signed-off-by: Greg Kurz <groug@kaod.org>
---
 hw/9pfs/9p.c | 70 +++++++++++++++++++++++++++++++++++++++++-----------
 hw/9pfs/9p.h |  1 +
 2 files changed, 57 insertions(+), 14 deletions(-)

diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index ba1ab920f1eb..5a895ae0bbfe 100644
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -573,10 +573,19 @@ static void coroutine_fn virtfs_reset(V9fsPDU *pdu)
                                 P9_STAT_MODE_SOCKET)
 
 /* This is the algorithm from ufs in spfs */
-static void stat_to_qid(const struct stat *stbuf, V9fsQID *qidp)
+static int stat_to_qid(V9fsPDU *pdu, const struct stat *stbuf, V9fsQID *qidp)
 {
     size_t size;
 
+    if (pdu->s->dev_id != stbuf->st_dev) {
+        warn_report_once(
+            "9p: Multiple devices detected in same VirtFS export, "
+            "which might lead to file ID collisions and severe "
+            "misbehaviours on guest! You should use a separate "
+            "export for each device shared from host."
+        );
+    }
+
     memset(&qidp->path, 0, sizeof(qidp->path));
     size = MIN(sizeof(stbuf->st_ino), sizeof(qidp->path));
     memcpy(&qidp->path, &stbuf->st_ino, size);
@@ -588,6 +597,8 @@ static void stat_to_qid(const struct stat *stbuf, V9fsQID *qidp)
     if (S_ISLNK(stbuf->st_mode)) {
         qidp->type |= P9_QID_TYPE_SYMLINK;
     }
+
+    return 0;
 }
 
 static int coroutine_fn fid_to_qid(V9fsPDU *pdu, V9fsFidState *fidp,
@@ -600,7 +611,10 @@ static int coroutine_fn fid_to_qid(V9fsPDU *pdu, V9fsFidState *fidp,
     if (err < 0) {
         return err;
     }
-    stat_to_qid(&stbuf, qidp);
+    err = stat_to_qid(pdu, &stbuf, qidp);
+    if (err < 0) {
+        return err;
+    }
     return 0;
 }
 
@@ -831,7 +845,10 @@ static int coroutine_fn stat_to_v9stat(V9fsPDU *pdu, V9fsPath *path,
 
     memset(v9stat, 0, sizeof(*v9stat));
 
-    stat_to_qid(stbuf, &v9stat->qid);
+    err = stat_to_qid(pdu, stbuf, &v9stat->qid);
+    if (err < 0) {
+        return err;
+    }
     v9stat->mode = stat_to_v9mode(stbuf);
     v9stat->atime = stbuf->st_atime;
     v9stat->mtime = stbuf->st_mtime;
@@ -892,7 +909,7 @@ static int coroutine_fn stat_to_v9stat(V9fsPDU *pdu, V9fsPath *path,
 #define P9_STATS_ALL           0x00003fffULL /* Mask for All fields above */
 
 
-static void stat_to_v9stat_dotl(V9fsState *s, const struct stat *stbuf,
+static int stat_to_v9stat_dotl(V9fsPDU *pdu, const struct stat *stbuf,
                                 V9fsStatDotl *v9lstat)
 {
     memset(v9lstat, 0, sizeof(*v9lstat));
@@ -914,7 +931,7 @@ static void stat_to_v9stat_dotl(V9fsState *s, const struct stat *stbuf,
     /* Currently we only support BASIC fields in stat */
     v9lstat->st_result_mask = P9_STATS_BASIC;
 
-    stat_to_qid(stbuf, &v9lstat->qid);
+    return stat_to_qid(pdu, stbuf, &v9lstat->qid);
 }
 
 static void print_sg(struct iovec *sg, int cnt)
@@ -1116,7 +1133,6 @@ static void coroutine_fn v9fs_getattr(void *opaque)
     uint64_t request_mask;
     V9fsStatDotl v9stat_dotl;
     V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
 
     retval = pdu_unmarshal(pdu, offset, "dq", &fid, &request_mask);
     if (retval < 0) {
@@ -1137,7 +1153,10 @@ static void coroutine_fn v9fs_getattr(void *opaque)
     if (retval < 0) {
         goto out;
     }
-    stat_to_v9stat_dotl(s, &stbuf, &v9stat_dotl);
+    retval = stat_to_v9stat_dotl(pdu, &stbuf, &v9stat_dotl);
+    if (retval < 0) {
+        goto out;
+    }
 
     /*  fill st_gen if requested and supported by underlying fs */
     if (request_mask & P9_STATS_GEN) {
@@ -1382,7 +1401,10 @@ static void coroutine_fn v9fs_walk(void *opaque)
             if (err < 0) {
                 goto out;
             }
-            stat_to_qid(&stbuf, &qid);
+            err = stat_to_qid(pdu, &stbuf, &qid);
+            if (err < 0) {
+                goto out;
+            }
             v9fs_path_copy(&dpath, &path);
         }
         memcpy(&qids[name_idx], &qid, sizeof(qid));
@@ -1484,7 +1506,10 @@ static void coroutine_fn v9fs_open(void *opaque)
     if (err < 0) {
         goto out;
     }
-    stat_to_qid(&stbuf, &qid);
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
     if (S_ISDIR(stbuf.st_mode)) {
         err = v9fs_co_opendir(pdu, fidp);
         if (err < 0) {
@@ -1594,7 +1619,10 @@ static void coroutine_fn v9fs_lcreate(void *opaque)
         fidp->flags |= FID_NON_RECLAIMABLE;
     }
     iounit =  get_iounit(pdu, &fidp->path);
-    stat_to_qid(&stbuf, &qid);
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
     err = pdu_marshal(pdu, offset, "Qd", &qid, iounit);
     if (err < 0) {
         goto out;
@@ -2328,7 +2356,10 @@ static void coroutine_fn v9fs_create(void *opaque)
         }
     }
     iounit = get_iounit(pdu, &fidp->path);
-    stat_to_qid(&stbuf, &qid);
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
     err = pdu_marshal(pdu, offset, "Qd", &qid, iounit);
     if (err < 0) {
         goto out;
@@ -2385,7 +2416,10 @@ static void coroutine_fn v9fs_symlink(void *opaque)
     if (err < 0) {
         goto out;
     }
-    stat_to_qid(&stbuf, &qid);
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
     err =  pdu_marshal(pdu, offset, "Q", &qid);
     if (err < 0) {
         goto out;
@@ -3065,7 +3099,10 @@ static void coroutine_fn v9fs_mknod(void *opaque)
     if (err < 0) {
         goto out;
     }
-    stat_to_qid(&stbuf, &qid);
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
     err = pdu_marshal(pdu, offset, "Q", &qid);
     if (err < 0) {
         goto out;
@@ -3223,7 +3260,10 @@ static void coroutine_fn v9fs_mkdir(void *opaque)
     if (err < 0) {
         goto out;
     }
-    stat_to_qid(&stbuf, &qid);
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
     err = pdu_marshal(pdu, offset, "Q", &qid);
     if (err < 0) {
         goto out;
@@ -3634,6 +3674,8 @@ int v9fs_device_realize_common(V9fsState *s, const V9fsTransport *t,
         goto out;
     }
 
+    s->dev_id = stat.st_dev;
+
     s->ctx.fst = &fse->fst;
     fsdev_throttle_init(s->ctx.fst);
 
diff --git a/hw/9pfs/9p.h b/hw/9pfs/9p.h
index 8883761b2c1d..5e316178d579 100644
--- a/hw/9pfs/9p.h
+++ b/hw/9pfs/9p.h
@@ -256,6 +256,7 @@ struct V9fsState
     Error *migration_blocker;
     V9fsConf fsconf;
     V9fsQID root_qid;
+    dev_t dev_id;
 };
 
 /* 9p2000.L open flags */
-- 
2.21.0

Re: [PULL 0/4] 9p patches 2019-10-08

[Greg Kurz]

Peter,

As said on IRC, please ignore this PR, I'm about to post a v2.
Sorry for the noise.

Cheers,

--
Greg

On Tue,  8 Oct 2019 17:19:21 +0200
Greg Kurz <groug@kaod.org> wrote:

> The following changes since commit 0f0b43868a566068fc137632fd51bd3cbb23f350:
> 
>   Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-4.2-20191004' into staging (2019-10-07 13:49:02 +0100)
> 
> are available in the Git repository at:
> 
>   https://github.com/gkurz/qemu.git tags/9p-next-2019-10-08
> 
> for you to fetch changes up to bc6c3cbf43dcc55e34e05bfcbd302bf1a4b92af7:
> 
>   9p: Treat multiple devices on one export as an error (2019-10-08 11:50:11 +0200)
> 
> ----------------------------------------------------------------
> The most notable change is to detect cross-device setups and warn the
> user that this may result in inode number collisions and chaos in the
> guest. The rest is cosmetic cleanup.
> 
> ----------------------------------------------------------------
> Antonios Motakis (2):
>       9p: unsigned type for type, version, path
>       9p: Treat multiple devices on one export as an error
> 
> Greg Kurz (2):
>       9p: Simplify error path of v9fs_device_realize_common()
>       fsdev: Add return value to fsdev_throttle_parse_opts()
> 
>  fsdev/9p-marshal.h          |  6 +--
>  fsdev/qemu-fsdev-throttle.c |  4 +-
>  fsdev/qemu-fsdev-throttle.h |  2 +-
>  hw/9pfs/9p-local.c          |  7 +++-
>  hw/9pfs/9p-proxy.c          |  4 ++
>  hw/9pfs/9p.c                | 92 ++++++++++++++++++++++++++++++++-------------
>  hw/9pfs/9p.h                |  1 +
>  hw/9pfs/trace-events        | 14 +++----
>  8 files changed, 88 insertions(+), 42 deletions(-)