search for: nrinfos

There's no substantial difference over v1, I simply fixed a few whitespace issues, moved one struct around and tidied up the comments. Rich.

..."newstyle negotiation: %s: export name too long", optname); if (send_newstyle_option_reply (conn, option, NBD_REP_ERR_INVALID) == -1) return -1; @@ -809,8 +812,8 @@ _negotiate_handshake_newstyle_options (struct connection *conn) memcpy (&nrinfos, &data[exportnamelen+4], 2); nrinfos = be16toh (nrinfos); if (optlen != 4 + exportnamelen + 2 + 2*nrinfos) { - debug ("newstyle negotiation: NBD_OPT_GO: " - "number of information requests incorrect"); + debug ("newsty...

...fo */ + debug ("newstyle negotiation: NBD_OPT_GO option length < 6"); + + if (send_newstyle_option_reply (conn, option, NBD_REP_ERR_INVALID) + == -1) + return -1; + continue; + } + + { + uint32_t exportnamelen; + uint16_t nrinfos; + uint16_t info; + size_t i; + CLEANUP_FREE char *requested_exportname = NULL; + + /* Validate the name length and number of INFO requests. */ + memcpy (&exportnamelen, &data[0], 4); + exportnamelen = be32toh (exportnamelen); + if (exportnam...

This is only lightly tested (against just qemu NBD client), and the code might be structured a little better as the _negotiate_handshake_newstyle_options function has now grown to be huge. Anyway works for me. Rich.

...namelen = htobe32 (strlen (export)); + /* For now, we make no NBD_INFO_* requests, relying on the server to + send its defaults. TODO: nbdkit should let plugins report block + sizes, at which point we should request NBD_INFO_BLOCK_SIZE and + obey any sizes set by server. */ + uint16_t nrinfos = htobe16 (0); + struct fixed_new_option_reply reply; + struct fixed_new_option_reply_info_export reply_export; + char *buffer; + uint16_t info; + + /* TODO: structured reads, block status */ + + /* Try NBD_OPT_GO */ + nbdkit_debug ("trying NBD_OPT_GO"); + opt.version = htobe64 (N...

Necessary when writing a client that wants to avoid unnecessary EINVAL errors from sending unaligned requests. At some point, we may want to add synchronous convenience API wrappers that do request splitting or read-modify-write to obey server constraints while still appearing to the library client as accepting any possible request. But such a wrapper should only be synchronous and not copied to

...o */ - debug ("newstyle negotiation: %s option length < 6", optname); - - if (send_newstyle_option_reply (conn, option, NBD_REP_ERR_INVALID) - == -1) - return -1; - continue; - } - - { - uint32_t exportnamelen; - uint16_t nrinfos; - uint16_t info; - size_t i; - CLEANUP_FREE char *requested_exportname = NULL; - - /* Validate the name length and number of INFO requests. */ - memcpy (&exportnamelen, &data[0], 4); - exportnamelen = be32toh (exportnamelen); - if (exportnam...

These are a couple of patches in preparation for the Block Status implementation. While the patches (especially the second one) are very large they are really just elementary code motion. Rich.

...} + } + if (flags & NBD_REPLY_FLAG_DONE) SET_NEXT_STATE (%^FINISH_COMMAND); else diff --git a/lib/internal.h b/lib/internal.h index e7be05b..7ad6219 100644 --- a/lib/internal.h +++ b/lib/internal.h @@ -143,6 +143,7 @@ struct nbd_handle { uint32_t len; uint16_t nrinfos; uint32_t nrqueries; + uint64_t offset; } sbuf; /* Issuing a command must use a buffer separate from sbuf, for the -- 2.20.1

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

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):

...return 0; diff --git a/generator/states-newstyle-opt-go.c b/generator/states-newstyle-opt-go.c index eea70cb..06bbaca 100644 --- a/generator/states-newstyle-opt-go.c +++ b/generator/states-newstyle-opt-go.c @@ -26,6 +26,7 @@ htobe32 (/* exportnamelen */ 4 + strlen (h->export_name) + /* nrinfos */ 2); h->wbuf = &h->sbuf; h->wlen = sizeof h->sbuf.option; + h->wflags = MSG_MORE; SET_NEXT_STATE (%SEND); return 0; @@ -38,6 +39,7 @@ h->sbuf.len = htobe32 (exportnamelen); h->wbuf = &h->sbuf; h->wlen = 4; + h->wflags = MSG_MO...

...querylen = htobe32 (strlen (query)); - /* For now, we make no NBD_INFO_* requests, relying on the server to - send its defaults. TODO: nbdkit should let plugins report block - sizes, at which point we should request NBD_INFO_BLOCK_SIZE and - obey any sizes set by server. */ - uint16_t nrinfos = htobe16 (0); - struct fixed_new_option_reply reply; - - nbdkit_debug ("trying NBD_OPT_STRUCTURED_REPLY"); - opt.version = htobe64 (NEW_VERSION); - opt.option = htobe32 (NBD_OPT_STRUCTURED_REPLY); - opt.optlen = htobe32 (0); - if (write_full (h->fd, &opt, sizeof opt)) { -...

...querylen = htobe32 (strlen (query)); - /* For now, we make no NBD_INFO_* requests, relying on the server to - send its defaults. TODO: nbdkit should let plugins report block - sizes, at which point we should request NBD_INFO_BLOCK_SIZE and - obey any sizes set by server. */ - uint16_t nrinfos = htobe16 (0); - struct fixed_new_option_reply reply; - - nbdkit_debug ("trying NBD_OPT_STRUCTURED_REPLY"); - opt.version = htobe64 (NEW_VERSION); - opt.option = htobe32 (NBD_OPT_STRUCTURED_REPLY); - opt.optlen = htobe32 (0); - if (write_full (h->fd, &opt, sizeof opt)) { -...

...querylen = htobe32 (strlen (query)); - /* For now, we make no NBD_INFO_* requests, relying on the server to - send its defaults. TODO: nbdkit should let plugins report block - sizes, at which point we should request NBD_INFO_BLOCK_SIZE and - obey any sizes set by server. */ - uint16_t nrinfos = htobe16 (0); - struct nbd_fixed_new_option_reply reply; - - nbdkit_debug ("trying NBD_OPT_STRUCTURED_REPLY"); - opt.version = htobe64 (NBD_NEW_VERSION); - opt.option = htobe32 (NBD_OPT_STRUCTURED_REPLY); - opt.optlen = htobe32 (0); - if (write_full (h->fd, &opt, sizeof opt)...

...lib/internal.h index ccaca32..998ca3d 100644 --- a/lib/internal.h +++ b/lib/internal.h @@ -157,6 +157,7 @@ struct nbd_handle { } __attribute__((packed)) error; } payload; } __attribute__((packed)) sr; + uint16_t gflags; uint32_t cflags; uint32_t len; uint16_t nrinfos; diff --git a/lib/nbd-protocol.h b/lib/nbd-protocol.h index 04e93d3..699aa22 100644 --- a/lib/nbd-protocol.h +++ b/lib/nbd-protocol.h @@ -93,9 +93,10 @@ struct nbd_fixed_new_option_reply { #define NBD_REP_MAGIC UINT64_C(0x3e889045565a9) -/* Global flags. */ +/* Global flags. Exposed by the gener...

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

...ow we send NBD_INFO_NAME if requested, and ignore all + * other info requests (including NBD_INFO_EXPORT if it was + * requested, because we replied already above). + * XXX NBD_INFO_DESCRIPTION is easy once we add .export_description. */ for (i = 0; i < nrinfos; ++i) { memcpy (&info, &data[4 + exportnamelen + 2 + i*2], 2); info = be16toh (info); switch (info) { case NBD_INFO_EXPORT: /* ignore - reply sent above */ break; + case NBD_INFO_NAME: + { + const char *name = &amp...

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: