search for: reply_cmd

...ply-simple.c b/generator/states-reply-simple.c index 7e5340c..12536e0 100644 --- a/generator/states-reply-simple.c +++ b/generator/states-reply-simple.c @@ -20,24 +20,15 @@ /* STATE MACHINE */ { REPLY.SIMPLE_REPLY.START: - struct command_in_flight *cmd; + struct command_in_flight *cmd = h->reply_cmd; uint32_t error; uint64_t handle; error = be32toh (h->sbuf.simple_reply.error); handle = be64toh (h->sbuf.simple_reply.handle); - /* Find the command amongst the commands in flight. */ - for (cmd = h->cmds_in_flight; cmd != NULL; cmd = cmd->next) { - if (cmd->handl...

...parsing a reply, requiring us to block + * until POLLIN, we instead track where in the state machine we left + * off, then return to READY to actually block. Then, on entry to + * REPLY.START, we can tell if this is the start of a new reply (rlen + * is 0, stay put), a continuation of the preamble (reply_cmd is NULL, + * resume with RECV_REPLY), or a continuation from any other location + * (reply_cmd contains the state to jump to). + */ + +static void +save_reply_state (struct nbd_handle *h) +{ + assert (h->reply_cmd); + assert (h->rlen); + h->reply_cmd->state = get_next_state (h); +} +...

...uiring us to block > + * until POLLIN, we instead track where in the state machine we left > + * off, then return to READY to actually block. Then, on entry to > + * REPLY.START, we can tell if this is the start of a new reply (rlen > + * is 0, stay put), a continuation of the preamble (reply_cmd is NULL, > + * resume with RECV_REPLY), or a continuation from any other location > + * (reply_cmd contains the state to jump to). > + */ > + > +static void > +save_reply_state (struct nbd_handle *h) > +{ > + assert (h->reply_cmd); > + assert (h->rlen); > + h-...

This was v3 patch 2/22, reworked to address the confusion about how a structured reply header is read in two pieces before getting to the payload portion. I'm still working on rebasing the rest of my v3 series (patches 1, 3-22) from other comments given, but this seemed independent enough that it's worth posting now rather than holding it up for the rest of the series. Eric Blake (4):

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

...structured.c b/generator/states-reply-structured.c index 20b0e9e..ff5b727 100644 --- a/generator/states-reply-structured.c +++ b/generator/states-reply-structured.c @@ -540,11 +540,20 @@ valid_flags (struct nbd_handle *h) return 0; REPLY.STRUCTURED_REPLY.FINISH: + struct command *cmd = h->reply_cmd; uint16_t flags; flags = be16toh (h->sbuf.sr.structured_reply.flags); - if (flags & NBD_REPLY_FLAG_DONE) + if (flags & NBD_REPLY_FLAG_DONE) { + if (cmd->type == NBD_CMD_BLOCK_STATUS && cmd->cb.fn.extent) + cmd->cb.fn.extent (LIBNBD_CALLBACK_FREE, cmd-&gt...

...cmd->error = error ? error : EPROTO; - if (flags & NBD_REPLY_FLAG_DONE) - FREE_CALLBACK (cmd->cb.fn.extent); } else /* Emit a debug message, but ignore it. */ @@ -530,17 +518,11 @@ return 0; REPLY.STRUCTURED_REPLY.FINISH: - struct command *cmd = h->reply_cmd; uint16_t flags; flags = be16toh (h->sbuf.sr.structured_reply.flags); - if (flags & NBD_REPLY_FLAG_DONE) { - if (cmd->type == NBD_CMD_BLOCK_STATUS) - FREE_CALLBACK (cmd->cb.fn.extent); - if (cmd->type == NBD_CMD_READ) - FREE_CALLBACK (cmd->cb.fn.chunk); +...

...diff --git a/generator/states-reply-simple.c b/generator/states-reply-simple.c index 935f6d2..ddc91ce 100644 --- a/generator/states-reply-simple.c +++ b/generator/states-reply-simple.c @@ -49,9 +49,22 @@ return 0; REPLY.SIMPLE_REPLY.RECV_READ_PAYLOAD: + struct command_in_flight *cmd = h->reply_cmd; + switch (recv_into_rbuf (h)) { case -1: SET_NEXT_STATE (%.DEAD); return -1; - case 0: SET_NEXT_STATE (%^FINISH_COMMAND); + case 0: + /* guaranteed by START */ + assert (cmd); + if (cmd->cb.fn.read) { + assert (cmd->error == 0); + errno = 0; + if (cmd->cb....

...diff --git a/generator/states-reply-simple.c b/generator/states-reply-simple.c index 935f6d2..87622a0 100644 --- a/generator/states-reply-simple.c +++ b/generator/states-reply-simple.c @@ -49,9 +49,22 @@ return 0; REPLY.SIMPLE_REPLY.RECV_READ_PAYLOAD: + struct command_in_flight *cmd = h->reply_cmd; + switch (recv_into_rbuf (h)) { case -1: SET_NEXT_STATE (%.DEAD); return -1; - case 0: SET_NEXT_STATE (%^FINISH_COMMAND); + case 0: + /* guaranteed by START */ + assert (cmd); + if (cmd->cb.fn.read) { + assert (cmd->error == 0); + errno = 0; + if (cmd->cb....

...if (flags & NBD_REPLY_FLAG_DONE) > - FREE_CALLBACK (cmd->cb.fn.extent); > } > else > /* Emit a debug message, but ignore it. */ > @@ -530,17 +518,11 @@ > return 0; > > REPLY.STRUCTURED_REPLY.FINISH: > - struct command *cmd = h->reply_cmd; > uint16_t flags; > > flags = be16toh (h->sbuf.sr.structured_reply.flags); > - if (flags & NBD_REPLY_FLAG_DONE) { > - if (cmd->type == NBD_CMD_BLOCK_STATUS) > - FREE_CALLBACK (cmd->cb.fn.extent); > - if (cmd->type == NBD_CMD_READ) > -...

...--git a/lib/internal.h b/lib/internal.h index 88ad703..11e0db6 100644 --- a/lib/internal.h +++ b/lib/internal.h @@ -191,6 +191,8 @@ struct nbd_handle { struct command_in_flight *cmds_to_issue, *cmds_in_flight, *cmds_done; /* Current command during a REPLY cycle */ struct command_in_flight *reply_cmd; + + bool disconnect_request; /* True if we've sent NBD_CMD_DISC */ }; struct meta_context { diff --git a/lib/rw.c b/lib/rw.c index 2dc60de..6b57f11 100644 --- a/lib/rw.c +++ b/lib/rw.c @@ -163,6 +163,11 @@ nbd_internal_command_common (struct nbd_handle *h, { struct command_in_flig...

...gt; diff --git a/generator/states-reply-chunk.c b/generator/states-reply-chunk.c > index 17bb5149..735f9456 100644 > --- a/generator/states-reply-chunk.c > +++ b/generator/states-reply-chunk.c > @@ -461,6 +461,11 @@ REPLY.CHUNK_REPLY.RECV_BS_ENTRIES: > struct command *cmd = h->reply_cmd; > size_t i; > uint32_t context_id; > + int error; > + const char *name; > + uint32_t orig_len, len, flags; > + uint64_t total, cap; > + bool stop; > > switch (recv_into_rbuf (h)) { > case -1: SET_NEXT_STATE (%.DEAD); return 0; > @@ -481,30 +486,63...

...offsetof (union reply_header, cookie), > + _cookie_aliasing_simple); > + STATIC_ASSERT (offsetof (union reply_header, structured.cookie) == > + offsetof (union reply_header, cookie), > + _cookie_aliasing_structured); > assert (h->reply_cmd == NULL); > assert (h->rlen == 0); > > - h->rbuf = &h->sbuf; > - h->rlen = sizeof h->sbuf.simple_reply; > + h->rbuf = &h->sbuf.reply.hdr; > + h->rlen = sizeof h->sbuf.reply.hdr.simple; > > r = h->sock->ops->recv (h, h-&...

...struct command *prev_cmd, *cmd; uint64_t cookie; + bool retire; /* NB: This works for both simple and structured replies because the * handle (our cookie) is stored at the same offset. @@ -164,6 +165,23 @@ save_reply_state (struct nbd_handle *h) assert (cmd != NULL); assert (h->reply_cmd == cmd); h->reply_cmd = NULL; + retire = cmd->type == NBD_CMD_DISC; + + /* Notify the user */ + if (cmd->cb.callback) { + int error = cmd->error; + + assert (cmd->type != NBD_CMD_DISC); + switch (cmd->cb.callback (cmd->cb.user_data, cookie, &error)) { + ca...

...n -1; + return 0; } SET_NEXT_STATE (%.READY); diff --git a/generator/states-reply-simple.c b/generator/states-reply-simple.c index cab72d6..23b6b5f 100644 --- a/generator/states-reply-simple.c +++ b/generator/states-reply-simple.c @@ -52,7 +52,7 @@ struct command_in_flight *cmd = h->reply_cmd; switch (recv_into_rbuf (h)) { - case -1: SET_NEXT_STATE (%.DEAD); return -1; + case -1: SET_NEXT_STATE (%.DEAD); return 0; case 1: save_reply_state (h); SET_NEXT_STATE (%.READY); diff --git a/generator/states-reply-structured.c b/generator/states-reply-structured.c index 91c6215...

...program to - * acknowledge them. + * acknowledge them. in_flight tracks the combined length of the + * first two lists. */ struct command_in_flight *cmds_to_issue, *cmds_in_flight, *cmds_done; + int in_flight; /* Current command during a REPLY cycle */ struct command_in_flight *reply_cmd; diff --git a/lib/rw.c b/lib/rw.c index 6b57f11..53cd521 100644 --- a/lib/rw.c +++ b/lib/rw.c @@ -25,6 +25,7 @@ #include <inttypes.h> #include <errno.h> #include <assert.h> +#include <limits.h> #include "internal.h" @@ -167,6 +168,10 @@ nbd_internal_command_...

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

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

This is a combination of these two earlier series: https://www.redhat.com/archives/libguestfs/2019-August/msg00235.html https://www.redhat.com/archives/libguestfs/2019-August/msg00240.html plus changes to allow .callback = NULL / .free != NULL, and to reduce the complexity of freeing callbacks. Although it's rather long there's nothing complex here. We might consider squashing some