search for: nbd_mark_dead

...uint64_t offset; uint32_t count; + uint32_t err; struct transaction *next; }; @@ -137,6 +139,7 @@ struct handle { int fd; int flags; int64_t size; + bool structured; pthread_t reader; /* Prevents concurrent threads from interleaving writes to server */ @@ -230,9 +233,10 @@ nbd_mark_dead (struct handle *h) return -1; } -/* Find and remove the transaction corresponding to cookie from the list. */ +/* Find and possibly remove the transaction corresponding to cookie + from the list. */ static struct transaction * -find_trans_by_cookie (struct handle *h, uint64_t cookie) +find_...

Updated based on other changes that have happened in the meantime: - rely more on cleanup.h (throughout) - split structured read for easier review (patch 2 and 3 were combined in v1) - rely on nbdkit not leaking a server's partial answer (patch 3) - add tests (patch 5) - other bug fixes I found while testing it - drop EOVERFLOW patch for now; it will be separate once upstream NBD protocol

I'm hoping to implement .extents for the nbd plugin; this is a prerequisite. I'm not sure about patch 3 - if we like it, I'll squash it to 2, if we don't, I think we are okay just dropping it. I'm also wondering if we have to worry about malicious plugins that don't populate the entire .pread buffer in an effort to get nbdkit to expose portions of the heap; my patch 7 loses

...truct handle *h) +{ + int r = pthread_mutex_unlock (&h->lock); + assert (!r); +} + /* Called during transmission phases when there is no hope of * resynchronizing with the server, and all further requests from the * client will fail. Returns -1 for convenience. */ @@ -187,6 +205,7 @@ nbd_mark_dead (struct handle *h) { int err = errno; + nbd_lock (h); if (!h->dead) { nbdkit_debug ("permanent failure while talking to server %s: %m", sockname); @@ -194,6 +213,7 @@ nbd_mark_dead (struct handle *h) } else if (!err) errno = ESHUTDOWN; + nbd...

...d/nbd.c | 232 ++++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 212 insertions(+), 20 deletions(-) > > + case NBD_STRUCTURED_REPLY_MAGIC: > + if (!h->structured) { > + nbdkit_error ("structured response without negotiation"); > + return nbd_mark_dead (h); > + } > + if (read_full (h->fd, sizeof rep.simple + (char *) &rep, > + sizeof rep - sizeof rep.simple)) > + return nbd_mark_dead (h); > + rep.structured.flags = be16toh (rep.structured.flags); > + rep.structured.type = be16toh (rep.st...

...;trans' between threads? plugins/nbd/nbd.c | 43 ++++++++++++++++++++++++++++++------------- 1 file changed, 30 insertions(+), 13 deletions(-) diff --git a/plugins/nbd/nbd.c b/plugins/nbd/nbd.c index e79042c..9d40e87 100644 --- a/plugins/nbd/nbd.c +++ b/plugins/nbd/nbd.c @@ -227,6 +227,26 @@ nbd_mark_dead (struct handle *h) return -1; } +/* Find and remove the transaction corresponding to cookie from the list. */ +static struct transaction * +find_trans_by_cookie (struct handle *h, uint64_t cookie) +{ + struct transaction **ptr; + struct transaction *trans; + + nbd_lock (h); + ptr = &h-...

With this, I am finally able to get the nbd plugin to do out-of-order responses to the client. Once this series goes in, we should be ready for Rich to cut a release. Eric Blake (4): nbd: Split reading into separate thread nbd: Protect writes with mutex nbd: Enable parallel handling tests: Test parallel nbd behavior plugins/nbd/nbd.c | 217

...) - continue; - return -1; - } - buf += r; - len -= r; - } - return 0; -} - -/* Called during transmission phases when there is no hope of - * resynchronizing with the server, and all further requests from the - * client will fail. Returns -1 for convenience. */ -static int -nbd_mark_dead (struct handle *h) -{ - int err = errno; - - ACQUIRE_LOCK_FOR_CURRENT_SCOPE (&h->trans_lock); - if (!h->dead) { - nbdkit_debug ("permanent failure while talking to server %s: %m", - servname); - h->dead = true; - } - else if (!err) - errno = ESH...

Patch 1 played with an early draft of Rich's Fedora 30 libnbd package: https://bugzilla.redhat.com/show_bug.cgi?id=1713767#c17 Note that comment 21 provides a newer package 0.1.1-1 with a different API; and that libnbd has more unreleased API changes in the pipeline (whether that will be called 0.2 or 0.1.2); so we'll have to tweak things based on what is actually available in distros.

libnbd-0.1.2-1 is now available in Fedora 29/30 updates-testing, although it was not compiled against libxml2 so it lacks uri support (I ended up testing patch 4 with a self-built libnbd). Diffs since v1 - rebase to master, bump from libnbd 0.1 to 0.1.2, add URI support, better timing results Still not done - patch 5 needs associated tests Eric Blake (5): nbd: Check for libnbd nbd:

libnbd-0.1.4-1 is now available in Fedora 29/30 updates testing. Diffs since v2 - rebase to master, bump from libnbd 0.1.2 to 0.1.3+, add tests to TLS usage which flushed out the need to turn relative pathnames into absolute, doc tweaks Now that the testsuite covers TLS and libnbd has been fixed to provide the things I found lacking when developing v2, I'm leaning towards pushing this on

I'm still working on the interleaving (and Rich reminded me on IRC that we still don't have THREAD_MODEL_PARALLEL working anywhere yet, anyways). Since nbdkit doesn't really have a parallel plugin yet, my testing on that front will have to use qemu-nbd as the original server, as well as qemu-io as the driver (qemu-io's aio_read and aio_write commands can be used to trigger

...) + continue; + return -1; + } + buf += r; + len -= r; + } + return 0; +} + +/* Called during transmission phases when there is no hope of + * resynchronizing with the server, and all further requests from the + * client will fail. Returns -1 for convenience. */ +static int +nbd_mark_dead (struct handle *h) +{ + int err = errno; + + if (!h->dead) { + nbdkit_debug ("permanent failure while talking to server %s: %m", + sockname); + h->dead = true; + } + else if (!err) + errno = ESHUTDOWN; + /* NBD only accepts a limited set of errno value...

...x, cookie %#" PRIx64, type, name_of_nbd_cmd(type), + flags, offset, count, cookie); r = write_full (h->fd, &req, sizeof req); if (buf && !r) r = write_full (h->fd, buf, count); @@ -353,7 +354,8 @@ nbd_reply_raw (struct handle *h, int *fd) return nbd_mark_dead (h); if (be32toh (rep.magic) != NBD_REPLY_MAGIC) return nbd_mark_dead (h); - nbdkit_debug ("received reply for cookie %#" PRIx64, rep.handle); + nbdkit_debug ("received reply for cookie %#" PRIx64 ", status %s", + rep.handle, name_of_nbd_error(...

...return trans; trans = find_trans_by_cookie (h, cookie, true); err: err = errno; - if (trans) { - close (trans->u.fds[0]); - close (trans->u.fds[1]); - free (trans); - } - else - close (fd); + if (sem_destroy (&trans->sem)) + abort (); + free (trans); + nbd_mark_dead (h); errno = err; - return nbd_mark_dead (h); + return NULL; } /* Shorthand for nbd_request_full when no extra buffers are involved. */ -static int +static struct transaction * nbd_request (struct handle *h, uint16_t flags, uint16_t type, uint64_t offset, uint32_t count) {...

...t; - struct reply rep; > + struct simple_reply rep; > struct transaction *trans; > void *buf; > uint32_t count; > @@ -353,7 +353,7 @@ nbd_reply_raw (struct handle *h, int *fd) > *fd = -1; > if (read_full (h->fd, &rep, sizeof rep) < 0) > return nbd_mark_dead (h); > - if (be32toh (rep.magic) != NBD_REPLY_MAGIC) > + if (be32toh (rep.magic) != NBD_SIMPLE_REPLY_MAGIC) > return nbd_mark_dead (h); > nbdkit_debug ("received reply for cookie %#" PRIx64 ", status %s", > rep.handle, name_of_nbd_error(...

...e, name_of_nbd_cmd(type), > + flags, offset, count, cookie); > r = write_full (h->fd, &req, sizeof req); > if (buf && !r) > r = write_full (h->fd, buf, count); > @@ -353,7 +354,8 @@ nbd_reply_raw (struct handle *h, int *fd) > return nbd_mark_dead (h); > if (be32toh (rep.magic) != NBD_REPLY_MAGIC) > return nbd_mark_dead (h); > - nbdkit_debug ("received reply for cookie %#" PRIx64, rep.handle); > + nbdkit_debug ("received reply for cookie %#" PRIx64 ", status %s", > + rep.h...

...d_reply_raw (struct handle *h, int *fd) { - struct reply rep; + struct simple_reply rep; struct transaction *trans; void *buf; uint32_t count; @@ -353,7 +353,7 @@ nbd_reply_raw (struct handle *h, int *fd) *fd = -1; if (read_full (h->fd, &rep, sizeof rep) < 0) return nbd_mark_dead (h); - if (be32toh (rep.magic) != NBD_REPLY_MAGIC) + if (be32toh (rep.magic) != NBD_SIMPLE_REPLY_MAGIC) return nbd_mark_dead (h); nbdkit_debug ("received reply for cookie %#" PRIx64 ", status %s", rep.handle, name_of_nbd_error(be32toh (rep.error))); di...

With some crufty sed scripts we can generate functions that map from NBD protocol flags (eg. NBD_CMD_READ) to strings ("NBD_CMD_READ"). This works on GNU sed and with FreeBSD, also with GNU sed's --posix option, so I guess the sed code is POSIX-compatible. Rich.

...; + buf = trans->buf; + count = trans->count; + free (trans); switch (be32toh (rep.error)) { case NBD_SUCCESS: - if (trans->buf && read_full (h->fd, trans->buf, trans->count) < 0) + if (buf && read_full (h->fd, buf, count) < 0) return nbd_mark_dead (h); return 0; case NBD_EPERM: @@ -399,6 +404,7 @@ nbd_reader (void *handle) abort (); } close (trans->u.fds[1]); + free (trans); } return NULL; } -- 2.14.3