search for: nbd_flag_send_flush

...+ if (fl == -1) + 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) { +...

...NBD_FLAG_HAS_FLAGS; 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...

...Copyright (C) 2017-2020 Red Hat Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are @@ -1175,7 +1175,7 @@ nbd_can_flush (void *handle) { struct handle *h = handle; - return h->flags & NBD_FLAG_SEND_FLUSH; + return !!(h->flags & NBD_FLAG_SEND_FLUSH); } static int @@ -1183,7 +1183,7 @@ nbd_is_rotational (void *handle) { struct handle *h = handle; - return h->flags & NBD_FLAG_ROTATIONAL; + return !!(h->flags & NBD_FLAG_ROTATIONAL); } static int @@ -1191,7 +1191,7 @@...

...; * > * Redistribution and use in source and binary forms, with or without > * modification, are permitted provided that the following conditions are > @@ -1175,7 +1175,7 @@ nbd_can_flush (void *handle) > { > struct handle *h = handle; > > - return h->flags & NBD_FLAG_SEND_FLUSH; > + return !!(h->flags & NBD_FLAG_SEND_FLUSH); > } > > static int > @@ -1183,7 +1183,7 @@ nbd_is_rotational (void *handle) > { > struct handle *h = handle; > > - return h->flags & NBD_FLAG_ROTATIONAL; > + return !!(h->flags & NBD_FLAG_R...

...= 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 (struct connection *conn, *error = EINVAL; return false; } - if (!conn->can_flush && (flags & NBD_CMD_FLAG_FUA)) { + if (!conn->can_fua &...

...onnection *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 = backend->is_rotational (backend, conn); @@ -460,7 +460,7 @@ compute_eflags (struct connection *conn, uint16_t *flags) return -1; if (fl) { eflags |= NBD_FLAG_ROTATIONAL; - conn->is_rotational = 1; +...

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

...tern const char *name_of_nbd_global_flag (int); #define NBD_FLAG_FIXED_NEWSTYLE 1 #define NBD_FLAG_NO_ZEROES 2 /* Per-export flags. */ +extern const char *name_of_nbd_flag (int); #define NBD_FLAG_HAS_FLAGS (1 << 0) #define NBD_FLAG_READ_ONLY (1 << 1) #define NBD_FLAG_SEND_FLUSH (1 << 2) @@ -94,6 +96,7 @@ struct fixed_new_option_reply { #define NBD_FLAG_SEND_WRITE_ZEROES (1 << 6) /* NBD options (new style handshake only). */ +extern const char *name_of_nbd_opt (int); #define NBD_OPT_EXPORT_NAME 1 #define NBD_OPT_ABORT 2 #define NBD_OPT_LIS...

Either patch 1 or patch 2 in isolation is sufficient to fix the problem that Rich forwarded on from an archlinux tester (name so I can credit them?). But both patches should be applied, as well as backported to appropriate stable branches, to maximize cross-version interoperability of nbdkit vs. plugins. Patch 3 will let us detect future similar bugs much faster. I want patch 4 to ensure that

...tern const char *name_of_nbd_global_flag (int); #define NBD_FLAG_FIXED_NEWSTYLE 1 #define NBD_FLAG_NO_ZEROES 2 /* Per-export flags. */ -extern const char *name_of_nbd_flag (int); #define NBD_FLAG_HAS_FLAGS (1 << 0) #define NBD_FLAG_READ_ONLY (1 << 1) #define NBD_FLAG_SEND_FLUSH (1 << 2) @@ -99,7 +97,6 @@ extern const char *name_of_nbd_flag (int); #define NBD_FLAG_SEND_FAST_ZERO (1 << 11) /* NBD options (new style handshake only). */ -extern const char *name_of_nbd_opt (int); #define NBD_OPT_EXPORT_NAME 1 #define NBD_OPT_ABORT...

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.

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

...write) + eflags |= NBD_FLAG_SEND_TRIM; + + fl = backend_can_fua (backend, conn); + if (fl == -1) + return -1; + if (fl && can_write) + eflags |= NBD_FLAG_SEND_FUA; fl = backend_can_flush (backend, conn); if (fl == -1) return -1; - if (fl) { + if (fl) eflags |= NBD_FLAG_SEND_FLUSH; - conn->can_flush = true; - } fl = backend_is_rotational (backend, conn); if (fl == -1) return -1; - if (fl) { + if (fl) eflags |= NBD_FLAG_ROTATIONAL; - conn->is_rotational = true; - } - /* multi-conn is useless if parallel connections are not allowed */ - if (...

With some crufty sed scripts we can generate functions that map from NBD protocol flags (eg. NBD_CMD_READ) to strings ("NBD_CMD_READ"). This works on GNU sed and with FreeBSD, also with GNU sed's --posix option, so I guess the sed code is POSIX-compatible. Rich.

...+{ + struct handle *h = handle; + + return h->size; +} + +static int +nbd_can_write (void *handle) +{ + struct handle *h = handle; + + return !(h->flags & NBD_FLAG_READ_ONLY); +} + +static int +nbd_can_flush (void *handle) +{ + struct handle *h = handle; + + return h->flags & NBD_FLAG_SEND_FLUSH; +} + +static int +nbd_is_rotational (void *handle) +{ + struct handle *h = handle; + + return h->flags & NBD_FLAG_ROTATIONAL; +} + +static int +nbd_can_trim (void *handle) +{ + struct handle *h = handle; + + return h->flags & NBD_FLAG_SEND_TRIM; +} + +/* Read data from the file....

...; - } - - 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; - if (fl) { - eflags |= NBD_FLAG_ROTATIONAL; - conn->is_rotational = true; - } - - fl = backend->can_multi_conn (backend, conn); - if (fl == -1) - return -1...

...) +{ + struct handle *h = handle; + + return h->size; +} + +static int nbd_can_write (void *handle) +{ + struct handle *h = handle; + + return !(h->flags & NBD_FLAG_READ_ONLY); +} + +static int nbd_can_flush (void *handle) +{ + struct handle *h = handle; + + return h->flags & NBD_FLAG_SEND_FLUSH; +} + +static int nbd_is_rotational (void *handle) +{ + struct handle *h = handle; + + return h->flags & NBD_FLAG_ROTATIONAL; +} + +static int nbd_can_trim (void *handle) +{ + struct handle *h = handle; + + return h->flags & NBD_FLAG_SEND_TRIM; +} + +static int nbd_request (struct...

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.

...== -1) { + nbdkit_error ("failure to check readonly flag: %s", nbd_get_error ()); + return -1; + } + return !(i || h->readonly); } static int nbdplug_can_flush (void *handle) { struct handle *h = handle; + int i = nbd_can_flush (h->nbd); - return h->flags & NBD_FLAG_SEND_FLUSH; + if (i == -1) { + nbdkit_error ("failure to check flush flag: %s", nbd_get_error ()); + return -1; + } + return i; } static int nbdplug_is_rotational (void *handle) { struct handle *h = handle; + int i = nbd_is_rotational (h->nbd); - return h->flags & NBD_F...