search for: nbd_flag_send_fua

...return -1; + if (readonly || !fl) { + eflags |= NBD_FLAG_READ_ONLY; + conn->readonly = 1; + } + if (!conn->readonly) { + eflags |= NBD_FLAG_SEND_WRITE_ZEROES; + } + + fl = plugin_can_flush (conn); + if (fl == -1) + return -1; + if (fl) { + eflags |= NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA; + conn->can_flush = 1; + } + + fl = plugin_is_rotational (conn); + if (fl == -1) + return -1; + if (fl) { + eflags |= NBD_FLAG_ROTATIONAL; + conn->is_rotational = 1; + } + + fl = plugin_can_trim (conn); + if (fl == -1) + return -1; + if (fl) { + eflags |= NBD_FLAG_S...

...fl = plugin_can_write (conn); if (fl == -1) return -1; if (readonly || !fl) { - eflags |= NBD_FLAG_READ_ONLY; + flags |= NBD_FLAG_READ_ONLY; conn->readonly = 1; } @@ -184,7 +183,7 @@ if (fl == -1) return -1; if (fl) { - eflags |= NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA; + flags |= NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA; conn->can_flush = 1; } @@ -192,7 +191,7 @@ if (fl == -1) return -1; if (fl) { - eflags |= NBD_FLAG_ROTATIONAL; + flags |= NBD_FLAG_ROTATIONAL; conn->is_rotational = 1; } @@ -200,7 +199,7 @@ if (fl...

..., conn); if (fl == -1) @@ -435,13 +443,21 @@ compute_eflags (struct connection *conn, uint16_t *flags) eflags |= NBD_FLAG_SEND_TRIM; conn->can_trim = 1; } + + fl = backend->can_fua (backend, conn); + if (fl == -1) + return -1; + if (fl) { + eflags |= NBD_FLAG_SEND_FUA; + conn->can_fua = 1; + } } fl = backend->can_flush (backend, conn); if (fl == -1) return -1; if (fl) { - eflags |= NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA; + eflags |= NBD_FLAG_SEND_FLUSH; conn->can_flush = 1; } @@ -880,7 +896,7 @@ validate_request...

The upstream protocol recently promoted NBD_CMD_WRITE_ZEROES from experimental to a documented extension. Exposing support for this allows plugin writers to create sparse files when driven by a client that knows how to use the extension; meanwhile, even if a plugin does not support this extension, the server benefits from less network traffic from the client. Eric Blake (5): protocol: Support

...st that did not match eflags. + */ + fl = backend_can_zero (backend, conn); + if (fl == -1) + return -1; + if (fl && can_write) + eflags |= NBD_FLAG_SEND_WRITE_ZEROES; - fl = backend_can_fua (backend, conn); - if (fl == -1) - return -1; - if (fl) { - eflags |= NBD_FLAG_SEND_FUA; - conn->can_fua = true; - } - } + fl = backend_can_trim (backend, conn); + if (fl == -1) + return -1; + if (fl && can_write) + eflags |= NBD_FLAG_SEND_TRIM; + + fl = backend_can_fua (backend, conn); + if (fl == -1) + return -1; + if (fl && can_write) +...

This is a subset of the last half of the larger 9-patch series. The uncontroversial first half of that series is pushed, but here, I tried to reduce the size of the patches by splitting out some of the more complex changes, so that the rest of the changes remaining in the series are more mechanical. In turn, it forced me to write timing tests, which let me spot another spot where we are wasting

Tested via: term1$ qemu-nbd -k $PWD/sock -t -f raw -x foo junk --trace=nbd_\* term2$ ./nbdkit -f -v -e bar nbd socket=$PWD/sock export=foo term3$ qemu-io -t none -f raw nbd://localhost:10809/bar --trace=nbd_\* and checking the traces to see that 'w 0 1' vs. 'w -f 0 1' was able to influence whether the FUA flag showed up at the server in term1. Still to go: figure out how to

...if (fl) { eflags |= NBD_FLAG_SEND_TRIM; - conn->can_trim = 1; + conn->can_trim = true; } fl = backend->can_fua (backend, conn); @@ -443,7 +443,7 @@ compute_eflags (struct connection *conn, uint16_t *flags) return -1; if (fl) { eflags |= NBD_FLAG_SEND_FUA; - conn->can_fua = 1; + conn->can_fua = true; } } @@ -452,7 +452,7 @@ compute_eflags (struct connection *conn, uint16_t *flags) return -1; if (fl) { eflags |= NBD_FLAG_SEND_FLUSH; - conn->can_flush = 1; + conn->can_flush = true; } fl = back...

I still need to add testsuite coverage. Perhaps it might be easier if I create a new '--filter=log logfile=foo' filter that produces a log of which commands a client sent, then compare the log using a known client that uses write_zeroes (qemu-io works well) both with and without --filter=nozero to prove that the change in advertisement changes the commands sent over the wire (that would

Experimental and only very lightly tested so far. Rich.

...} - - fl = backend->can_trim (backend, conn); - if (fl == -1) - return -1; - if (fl) { - eflags |= NBD_FLAG_SEND_TRIM; - conn->can_trim = true; - } - - fl = backend->can_fua (backend, conn); - if (fl == -1) - return -1; - if (fl) { - eflags |= NBD_FLAG_SEND_FUA; - conn->can_fua = true; - } - } - - fl = backend->can_flush (backend, conn); - if (fl == -1) - return -1; - if (fl) { - eflags |= NBD_FLAG_SEND_FLUSH; - conn->can_flush = true; - } - - fl = backend->is_rotational (backend, conn); - if (fl == -1) - return -1;...

First thing to say is that I need to do a *lot* more testing on this, so this is just an early peek. In particular, although it passed ‘make check && make check-valgrind’ I have *not* tested it against a multi-conn-aware client such as the Linux kernel >= 4.9. This implements NBD_FLAG_CAN_MULTI_CONN, described in the protocol doc as: "NBD_FLAG_CAN_MULTI_CONN: Indicates that

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.

For existing commits, this is almost identical to v1, except that I updated some commit messages and reordered the commits in a somewhat more logical sequence. The main changes are the extra commits: [06/11] plugins: Return NBD_FLAG_CAN_MULTI_CONN from some readonly plugins. - Readonly plugins that can set the flag unconditionally. [09/11] partitioning: Return NBD_FLAG_CAN_MULTI_CONN. [10/11]

..._SEND_WRITE_ZEROES; + if (i == -1) { + nbdkit_error ("failure to check zero flag: %s", nbd_get_error ()); + return -1; + } + return i; } static int nbdplug_can_fua (void *handle) { struct handle *h = handle; + int i = nbd_can_fua (h->nbd); - return h->flags & NBD_FLAG_SEND_FUA ? NBDKIT_FUA_NATIVE : NBDKIT_FUA_NONE; + if (i == -1) { + nbdkit_error ("failure to check fua flag: %s", nbd_get_error ()); + return -1; + } + return i ? NBDKIT_FUA_NATIVE : NBDKIT_FUA_NONE; } static int nbdplug_can_multi_conn (void *handle) { struct handle *h = handle; +...

..._SEND_WRITE_ZEROES; + if (i == -1) { + nbdkit_error ("failure to check zero flag: %s", nbd_get_error ()); + return -1; + } + return i; } static int nbdplug_can_fua (void *handle) { struct handle *h = handle; + int i = nbd_can_fua (h->nbd); - return h->flags & NBD_FLAG_SEND_FUA ? NBDKIT_FUA_NATIVE : NBDKIT_FUA_NONE; + if (i == -1) { + nbdkit_error ("failure to check fua flag: %s", nbd_get_error ()); + return -1; + } + return i ? NBDKIT_FUA_NATIVE : NBDKIT_FUA_NONE; } static int nbdplug_can_multi_conn (void *handle) { struct handle *h = handle; +...

...return !!(h->flags & NBD_FLAG_SEND_TRIM); -} - -static int -nbd_can_zero (void *handle) -{ - struct handle *h = handle; - - return !!(h->flags & NBD_FLAG_SEND_WRITE_ZEROES); -} - -static int -nbd_can_fua (void *handle) -{ - struct handle *h = handle; - - return h->flags & NBD_FLAG_SEND_FUA ? NBDKIT_FUA_NATIVE : NBDKIT_FUA_NONE; -} - -static int -nbd_can_multi_conn (void *handle) -{ - struct handle *h = handle; - - return !!(h->flags & NBD_FLAG_CAN_MULTI_CONN); -} - -static int -nbd_can_cache (void *handle) -{ - struct handle *h = handle; - - if (h->flags & NBD_FLAG_...

...BD_FLAG_SEND_FAST_ZERO; - fl = backend_can_trim (backend); + fl = backend_can_trim (top); if (fl == -1) return -1; if (fl) eflags |= NBD_FLAG_SEND_TRIM; - fl = backend_can_fua (backend); + fl = backend_can_fua (top); if (fl == -1) return -1; if (fl) eflags |= NBD_FLAG_SEND_FUA; - fl = backend_can_flush (backend); + fl = backend_can_flush (top); if (fl == -1) return -1; if (fl) eflags |= NBD_FLAG_SEND_FLUSH; - fl = backend_is_rotational (backend); + fl = backend_is_rotational (top); if (fl == -1) return -1; if (fl) eflags |= NBD_FLA...

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: