search for: nbd_internal_set_size_and_flag

...x%" PRIx16, - conn->h->exportsize, conn->h->eflags); - if (conn->h->eflags == 0) { + uint64_t exportsize; + uint16_t eflags; + + exportsize = be64toh (conn->sbuf.export_name_reply.exportsize); + eflags = be16toh (conn->sbuf.export_name_reply.eflags); + if (nbd_internal_set_size_and_flags (conn->h, exportsize, eflags) == -1) { SET_NEXT_STATE (%.DEAD); - set_error (EINVAL, "handshake: invalid eflags == 0 from server"); return -1; } SET_NEXT_STATE (%.READY); diff --git a/generator/states-newstyle-opt-go.c b/generator/states-newstyle-opt-go.c index 4dbe...

Per recent discussion here: https://www.redhat.com/archives/libguestfs/2019-May/thread.html#00175

...connection objects, then call one of the +C<nbd_connect*> functions again on the handle to connect +the remaining connections."; }; "can_cache", { diff --git a/lib/flags.c b/lib/flags.c index 825b326..1956db6 100644 --- a/lib/flags.c +++ b/lib/flags.c @@ -42,6 +42,16 @@ nbd_internal_set_size_and_flags (struct nbd_handle *h, return -1; } + /* It is unsafe to connect to a server with multi-conn set unless + * the server says it is safe to do so. + */ + if (h->multi_conn > 1 && (eflags & NBD_FLAG_CAN_MULTI_CONN) == 0) { + set_error (EINVAL, "handshake: mul...

...;CMD_FLAG_FUA", 1 lsl 0; "CMD_FLAG_NO_HOLE", 1 lsl 1; + "CMD_FLAG_DF", 1 lsl 2; "CMD_FLAG_REQ_ONE", 1 lsl 3; ] diff --git a/lib/flags.c b/lib/flags.c index 421a7d2..cdbc28f 100644 --- a/lib/flags.c +++ b/lib/flags.c @@ -42,6 +42,11 @@ nbd_internal_set_size_and_flags (struct nbd_handle *h, return -1; } + if (eflags & NBD_FLAG_SEND_DF && !h->structured_replies) { + debug (h, "server lacks structured replies, ignoring claim of df"); + eflags &= ~NBD_FLAG_SEND_DF; + } + h->exportsize = exportsize; h->eflag...

...PT_EXPORT_NAME.RECV_REPLY: switch (recv_into_rbuf (h)) { - case -1: SET_NEXT_STATE (%.DEAD); return -1; + case -1: SET_NEXT_STATE (%.DEAD); return 0; case 0: SET_NEXT_STATE (%CHECK_REPLY); } return 0; @@ -66,7 +66,7 @@ eflags = be16toh (h->sbuf.export_name_reply.eflags); if (nbd_internal_set_size_and_flags (h, exportsize, eflags) == -1) { SET_NEXT_STATE (%.DEAD); - return -1; + return 0; } SET_NEXT_STATE (%.READY); return 0; diff --git a/generator/states-newstyle-opt-go.c b/generator/states-newstyle-opt-go.c index e245c75..49875a5 100644 --- a/generator/states-newstyle-opt-go.c +...

...dstyle.c +++ b/generator/states-oldstyle.c @@ -58,6 +58,11 @@ h->gflags = gflags; debug (h, "gflags: 0x%" PRIx16, gflags); + if (gflags) { + set_error (0, "handshake: oldstyle server should not set gflags"); + SET_NEXT_STATE (%.DEAD); + return 0; + } if (nbd_internal_set_size_and_flags (h, exportsize, eflags) == -1) { SET_NEXT_STATE (%.DEAD); diff --git a/lib/handle.c b/lib/handle.c index bc4206c..8ca2e5a 100644 --- a/lib/handle.c +++ b/lib/handle.c @@ -64,6 +64,8 @@ nbd_create (void) h->unique = 1; h->tls_verify_peer = true; h->request_sr = true; + h-&gt...

...losed (h->state) && + !nbd_internal_is_state_dead (h->state)) { if (nbd_unlocked_poll (h, -1) == -1) return -1; } diff --git a/lib/internal.h b/lib/internal.h index c1a57ac..691a1eb 100644 --- a/lib/internal.h +++ b/lib/internal.h @@ -264,6 +264,14 @@ extern int nbd_internal_set_size_and_flags (struct nbd_handle *h, uint64_t exportsize, uint16_t eflags); +/* is-state.c */ +extern bool nbd_internal_is_state_created (enum state state); +extern bool nbd_internal_is_state_connecting (enum state state...

...zeroes is no +faster than a normal write (if that is supported - some servers +cannot do this, see L<nbd_can_fast_zero(3)>)."; }; "block_status", { diff --git a/lib/flags.c b/lib/flags.c index 2bcacb8..d55d10a 100644 --- a/lib/flags.c +++ b/lib/flags.c @@ -47,6 +47,12 @@ nbd_internal_set_size_and_flags (struct nbd_handle *h, eflags &= ~NBD_FLAG_SEND_DF; } + if (eflags & NBD_FLAG_SEND_FAST_ZERO && + !(eflags & NBD_FLAG_SEND_WRITE_ZEROES)) { + debug (h, "server lacks write zeroes, ignoring claim of fast zero"); + eflags &= ~NBD_FLAG_SEND_FAST_...

...n_data && !data.seen_hole); /* Trigger a failed callback, to prove connection stays up. With * reads, all chunks trigger a callback even after failure, but the diff --git a/lib/flags.c b/lib/flags.c index 421a7d2..cdbc28f 100644 --- a/lib/flags.c +++ b/lib/flags.c @@ -42,6 +42,11 @@ nbd_internal_set_size_and_flags (struct nbd_handle *h, return -1; } + if (eflags & NBD_FLAG_SEND_DF && !h->structured_replies) { + debug (h, "server lacks structured replies, ignoring claim of df"); + eflags &= ~NBD_FLAG_SEND_DF; + } + h->exportsize = exportsize; h->eflag...

...e if we've queued NBD_CMD_DISC */ }; +struct free_callback { + void *ptr; + nbd_free_callback cb; + void *user_data; +}; + struct meta_context { struct meta_context *next; /* Linked list. */ char *name; /* Name of meta context. */ @@ -318,6 +329,9 @@ extern int nbd_internal_set_size_and_flags (struct nbd_handle *h, uint64_t exportsize, uint16_t eflags); +/* free.c */ +extern void nbd_internal_free_callback (struct nbd_handle *h, void *ptr); + /* is-state.c */ extern bool nbd_internal_is_state_...

This isn't quite finished because not all of the tests or examples have been updated, but it demonstrates an idea: Should we forget about the concept of having multiple connections managed under a single handle? In this patch there is a single ‘struct nbd_handle *’ which manages a single state machine and connection (and therefore no nbd_connection). To connect to a multi-conn server you must

I'm still playing with ideas on how to split rstate from wstate (so that we can send a request without waiting for POLLIN to complete a pending reply), but this is some preliminary refactoring I found useful. I also fixed a couple of bugs while in the area (already pushed). There's a question of whether we want nbd_handle to be nearly 5k, or if we should instead keep it small and add one

I still need to wire in the use of *_notify functions into nbdkit to prove whether it makes the code any faster or easier to maintain, but at least the added example shows one good use case for the new API. Eric Blake (6): api: Add nbd_aio_in_flight generator: Allow DEAD state actions to run generator: Allow Int64 in callbacks states: Prepare for aio notify callback api: Add new

I need to think about this patch series a bit more, but it does at least pass the tests. Rich.

RFC because this is an API break, but we haven't declared stable API yet. If we like it, I'm working on using libnbd to implement the nbdkit-nbd plugin; knowing whether it is API version 0.1 or 0.2 will be useful. I also dabbled with allowing optional parameters in python, although my OCaml is weak enough that there may be cleaner ways to approach that. Eric Blake (4): api: Add flags

Since v1: - rebase to applied patches - split out support for Int in callbacks - sort of test that callbacks work in OCaml (see comment in patch 5) - rename API to nbd_pread_structured - expose error as explicit parameter to callback Eric Blake (5): generator: Allow Int in callbacks states: Wire in a read callback states: Add nbd_pread_structured API states: Add tests for

As proposed here: https://www.redhat.com/archives/libguestfs/2019-August/msg00130.html I didn't actually read Eric's replies to that yet because I've been concentrating on writing these patches all day. Anyway here they are and I'll look at what Eric said about the proposal next. Rich.

I've mentioned this topic before (in fact, the idea of adding NBD_CMD_FLAG_DF was first mentioned at [1]), but finally finished enough of an implementation to feel confident in posting it. I'd still like to add something under examples/ that uses the new API to implement strict checking of a server's structured replies read implementation (ensure that a server never sends data after

This is a cover letter to a series of patches being proposed in tandem to four different projects: - nbd: Document a new NBD_CMD_FLAG_FAST_ZERO command flag - qemu: Implement the flag for both clients and server - libnbd: Implement the flag for clients - nbdkit: Implement the flag for servers, including the nbd passthrough client If you want to test the patches together, I've pushed a

Well, I'm not quite done (I still want to get nbdinfo to work on a single nbd connection for all cases when reading the heads of the file is not required), but I'm happy with patches 1-11, and 12-13 show where I'm headed for getting NBD_OPT_INFO to work. Posting now to see if some of the earlier patches are ready to commit while I continue working on the latter half. Eric Blake (13):