search for: nbd_unlocked_can_df

...lacks structured replies, ignoring claim of df"); + eflags &= ~NBD_FLAG_SEND_DF; + } + h->exportsize = exportsize; h->eflags = eflags; return 0; @@ -95,6 +100,12 @@ nbd_unlocked_can_zero (struct nbd_handle *h) return get_flag (h, NBD_FLAG_SEND_WRITE_ZEROES); } +int +nbd_unlocked_can_df (struct nbd_handle *h) +{ + return get_flag (h, NBD_FLAG_SEND_DF); +} + int nbd_unlocked_can_multi_conn (struct nbd_handle *h) { diff --git a/lib/rw.c b/lib/rw.c index feaf468..343c340 100644 --- a/lib/rw.c +++ b/lib/rw.c @@ -234,11 +234,17 @@ int64_t nbd_unlocked_aio_pread (struct nbd_handle...

...lacks structured replies, ignoring claim of df"); + eflags &= ~NBD_FLAG_SEND_DF; + } + h->exportsize = exportsize; h->eflags = eflags; return 0; @@ -95,6 +100,12 @@ nbd_unlocked_can_zero (struct nbd_handle *h) return get_flag (h, NBD_FLAG_SEND_WRITE_ZEROES); } +int +nbd_unlocked_can_df (struct nbd_handle *h) +{ + return get_flag (h, NBD_FLAG_SEND_DF); +} + int nbd_unlocked_can_multi_conn (struct nbd_handle *h) { diff --git a/lib/nbd-protocol.h b/lib/nbd-protocol.h index 071971e..405af3e 100644 --- a/lib/nbd-protocol.h +++ b/lib/nbd-protocol.h @@ -245,6 +245,7 @@ struct nbd_st...

...64_t offset, uint32_t flags) > { > - if (flags != 0) { > + if ((flags & ~LIBNBD_CMD_FLAG_DF) != 0) { > set_error (EINVAL, "invalid flag: %" PRIu32, flags); > return -1; > } > > + if ((flags & LIBNBD_CMD_FLAG_DF) != 0 && > + nbd_unlocked_can_df (h) != 1) { > + set_error (EINVAL, "server does not support the DF flag"); > + return -1; > + } I'm confused why you'd want to specify this flag to pread. From the caller point of view they shouldn't care about whether the reply on the wire is fragmented or n...

...PRIu32, flags); - return -1; - } + if (h->strict & LIBNBD_STRICT_COMMANDS) { + if ((flags & ~LIBNBD_CMD_FLAG_DF) != 0) { + set_error (EINVAL, "invalid flag: %" PRIu32, flags); + return -1; + } - if ((flags & LIBNBD_CMD_FLAG_DF) != 0 && - nbd_unlocked_can_df (h) != 1) { - set_error (EINVAL, "server does not support the DF flag"); - return -1; + if ((flags & LIBNBD_CMD_FLAG_DF) != 0 && + nbd_unlocked_can_df (h) != 1) { + set_error (EINVAL, "server does not support the DF flag"); + return -1; +...

...t; { >> - if (flags != 0) { >> + if ((flags & ~LIBNBD_CMD_FLAG_DF) != 0) { >> set_error (EINVAL, "invalid flag: %" PRIu32, flags); >> return -1; >> } >> >> + if ((flags & LIBNBD_CMD_FLAG_DF) != 0 && >> + nbd_unlocked_can_df (h) != 1) { >> + set_error (EINVAL, "server does not support the DF flag"); >> + return -1; >> + } > > I'm confused why you'd want to specify this flag to pread. From the > caller point of view they shouldn't care about whether the reply on...

...e25 100644 --- a/lib/rw.c +++ b/lib/rw.c @@ -295,10 +295,12 @@ nbd_unlocked_aio_pread_structured (struct nbd_handle *h, void *buf, struct command_cb cb = { .fn.chunk = *chunk, .completion = *completion }; - if ((flags & LIBNBD_CMD_FLAG_DF) != 0 && - nbd_unlocked_can_df (h) != 1) { - set_error (EINVAL, "server does not support the DF flag"); - return -1; + if (h->strict & LIBNBD_STRICT_COMMANDS) { + if ((flags & LIBNBD_CMD_FLAG_DF) != 0 && + nbd_unlocked_can_df (h) != 1) { + set_error (EINVAL, "server does no...

...tsize = exportsize; h->eflags = eflags; return 0; @@ -100,6 +106,12 @@ nbd_unlocked_can_zero (struct nbd_handle *h) return get_flag (h, NBD_FLAG_SEND_WRITE_ZEROES); } +int +nbd_unlocked_can_fast_zero (struct nbd_handle *h) +{ + return get_flag (h, NBD_FLAG_SEND_FAST_ZERO); +} + int nbd_unlocked_can_df (struct nbd_handle *h) { diff --git a/lib/protocol.c b/lib/protocol.c index 6087887..acee203 100644 --- a/lib/protocol.c +++ b/lib/protocol.c @@ -36,6 +36,7 @@ nbd_internal_errno_of_nbd_error (uint32_t error) case NBD_EINVAL: return EINVAL; case NBD_ENOSPC: return ENOSPC; case NBD_EOVERFL...

We have been inconsistent on how much we reject client-side without even consulting the server, vs. how much we depend on the server to detect failure (even if our request can be deemed undefined per NBD protocol). I'd like to change it so that by default, we reject as much as we can client-side for less traffic, but where the user can also change things on the fly for server-side integration

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

...command_cb cb = { .fn.chunk = *chunk, .completion = *completion }; - if ((flags & ~LIBNBD_CMD_FLAG_DF) != 0) { - set_error (EINVAL, "invalid flag: %" PRIu32, flags); - return -1; - } - if ((flags & LIBNBD_CMD_FLAG_DF) != 0 && nbd_unlocked_can_df (h) != 1) { set_error (EINVAL, "server does not support the DF flag"); @@ -334,11 +320,6 @@ nbd_unlocked_aio_pwrite (struct nbd_handle *h, const void *buf, return -1; } - if ((flags & ~LIBNBD_CMD_FLAG_FUA) != 0) { - set_error (EINVAL, "invalid flag: %" PRIu...

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

In v2: - now based on my proposal to add LIBNBD_SHUTDOWN_IMMEDIATE - four flags instead of two: STRICT_FLAGS is new (patch 4), and STRICT_BOUNDS is separate from STRICT_ZERO_SIZE (patch 5) - various refactorings for more shared code and less duplication Eric Blake (5): api: Add xxx_MASK constant for each Flags type generator: Refactor filtering of accepted OFlags api: Add

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