diff options
| -rw-r--r-- | include/block/nbd.h | 8 | ||||
| -rw-r--r-- | nbd/server.c | 137 | ||||
| -rw-r--r-- | nbd/trace-events | 8 |
3 files changed, 88 insertions, 65 deletions
diff --git a/include/block/nbd.h b/include/block/nbd.h index 9dcb5357d1..ee71af099a 100644 --- a/include/block/nbd.h +++ b/include/block/nbd.h @@ -97,28 +97,28 @@ typedef union NBDReply { /* Header of chunk for NBD_REPLY_TYPE_OFFSET_DATA */ typedef struct NBDStructuredReadData { - NBDStructuredReplyChunk h; /* h.length >= 9 */ + /* header's .length >= 9 */ uint64_t offset; /* At least one byte of data payload follows, calculated from h.length */ } QEMU_PACKED NBDStructuredReadData; /* Complete chunk for NBD_REPLY_TYPE_OFFSET_HOLE */ typedef struct NBDStructuredReadHole { - NBDStructuredReplyChunk h; /* h.length == 12 */ + /* header's length == 12 */ uint64_t offset; uint32_t length; } QEMU_PACKED NBDStructuredReadHole; /* Header of all NBD_REPLY_TYPE_ERROR* errors */ typedef struct NBDStructuredError { - NBDStructuredReplyChunk h; /* h.length >= 6 */ + /* header's length >= 6 */ uint32_t error; uint16_t message_length; } QEMU_PACKED NBDStructuredError; /* Header of NBD_REPLY_TYPE_BLOCK_STATUS */ typedef struct NBDStructuredMeta { - NBDStructuredReplyChunk h; /* h.length >= 12 (at least one extent) */ + /* header's length >= 12 (at least one extent) */ uint32_t context_id; /* extents follows */ } QEMU_PACKED NBDStructuredMeta; diff --git a/nbd/server.c b/nbd/server.c index febe001a39..6698ab4636 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2016-2022 Red Hat, Inc. + * Copyright Red Hat * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws> * * Network Block Device Server Side @@ -1906,16 +1906,36 @@ static int coroutine_fn nbd_co_send_simple_reply(NBDClient *client, {.iov_base = data, .iov_len = len} }; + assert(!len || !nbd_err); trace_nbd_co_send_simple_reply(handle, nbd_err, nbd_err_lookup(nbd_err), len); set_be_simple_reply(&reply, nbd_err, handle); - return nbd_co_send_iov(client, iov, len ? 2 : 1, errp); + return nbd_co_send_iov(client, iov, 2, errp); } -static inline void set_be_chunk(NBDStructuredReplyChunk *chunk, uint16_t flags, - uint16_t type, uint64_t handle, uint32_t length) +/* + * Prepare the header of a reply chunk for network transmission. + * + * On input, @iov is partially initialized: iov[0].iov_base must point + * to an uninitialized NBDReply, while the remaining @niov elements + * (if any) must be ready for transmission. This function then + * populates iov[0] for transmission. + */ +static inline void set_be_chunk(NBDClient *client, struct iovec *iov, + size_t niov, uint16_t flags, uint16_t type, + uint64_t handle) { + /* TODO - handle structured vs. extended replies */ + NBDStructuredReplyChunk *chunk = iov->iov_base; + size_t i, length = 0; + + for (i = 1; i < niov; i++) { + length += iov[i].iov_len; + } + assert(length <= NBD_MAX_BUFFER_SIZE + sizeof(NBDStructuredReadData)); + + iov[0].iov_len = sizeof(*chunk); stl_be_p(&chunk->magic, NBD_STRUCTURED_REPLY_MAGIC); stw_be_p(&chunk->flags, flags); stw_be_p(&chunk->type, type); @@ -1923,67 +1943,71 @@ static inline void set_be_chunk(NBDStructuredReplyChunk *chunk, uint16_t flags, stl_be_p(&chunk->length, length); } -static int coroutine_fn nbd_co_send_structured_done(NBDClient *client, - uint64_t handle, - Error **errp) +static int coroutine_fn nbd_co_send_chunk_done(NBDClient *client, + uint64_t handle, + Error **errp) { - NBDStructuredReplyChunk chunk; + NBDReply hdr; struct iovec iov[] = { - {.iov_base = &chunk, .iov_len = sizeof(chunk)}, + {.iov_base = &hdr}, }; - trace_nbd_co_send_structured_done(handle); - set_be_chunk(&chunk, NBD_REPLY_FLAG_DONE, NBD_REPLY_TYPE_NONE, handle, 0); + trace_nbd_co_send_chunk_done(handle); + set_be_chunk(client, iov, 1, NBD_REPLY_FLAG_DONE, + NBD_REPLY_TYPE_NONE, handle); return nbd_co_send_iov(client, iov, 1, errp); } -static int coroutine_fn nbd_co_send_structured_read(NBDClient *client, - uint64_t handle, - uint64_t offset, - void *data, - size_t size, - bool final, - Error **errp) +static int coroutine_fn nbd_co_send_chunk_read(NBDClient *client, + uint64_t handle, + uint64_t offset, + void *data, + size_t size, + bool final, + Error **errp) { + NBDReply hdr; NBDStructuredReadData chunk; struct iovec iov[] = { + {.iov_base = &hdr}, {.iov_base = &chunk, .iov_len = sizeof(chunk)}, {.iov_base = data, .iov_len = size} }; assert(size); - trace_nbd_co_send_structured_read(handle, offset, data, size); - set_be_chunk(&chunk.h, final ? NBD_REPLY_FLAG_DONE : 0, - NBD_REPLY_TYPE_OFFSET_DATA, handle, - sizeof(chunk) - sizeof(chunk.h) + size); + trace_nbd_co_send_chunk_read(handle, offset, data, size); + set_be_chunk(client, iov, 3, final ? NBD_REPLY_FLAG_DONE : 0, + NBD_REPLY_TYPE_OFFSET_DATA, handle); stq_be_p(&chunk.offset, offset); - return nbd_co_send_iov(client, iov, 2, errp); + return nbd_co_send_iov(client, iov, 3, errp); } -static int coroutine_fn nbd_co_send_structured_error(NBDClient *client, - uint64_t handle, - uint32_t error, - const char *msg, - Error **errp) +static int coroutine_fn nbd_co_send_chunk_error(NBDClient *client, + uint64_t handle, + uint32_t error, + const char *msg, + Error **errp) { + NBDReply hdr; NBDStructuredError chunk; int nbd_err = system_errno_to_nbd_errno(error); struct iovec iov[] = { + {.iov_base = &hdr}, {.iov_base = &chunk, .iov_len = sizeof(chunk)}, {.iov_base = (char *)msg, .iov_len = msg ? strlen(msg) : 0}, }; assert(nbd_err); - trace_nbd_co_send_structured_error(handle, nbd_err, - nbd_err_lookup(nbd_err), msg ? msg : ""); - set_be_chunk(&chunk.h, NBD_REPLY_FLAG_DONE, NBD_REPLY_TYPE_ERROR, handle, - sizeof(chunk) - sizeof(chunk.h) + iov[1].iov_len); + trace_nbd_co_send_chunk_error(handle, nbd_err, + nbd_err_lookup(nbd_err), msg ? msg : ""); + set_be_chunk(client, iov, 3, NBD_REPLY_FLAG_DONE, + NBD_REPLY_TYPE_ERROR, handle); stl_be_p(&chunk.error, nbd_err); - stw_be_p(&chunk.message_length, iov[1].iov_len); + stw_be_p(&chunk.message_length, iov[2].iov_len); - return nbd_co_send_iov(client, iov, 1 + !!iov[1].iov_len, errp); + return nbd_co_send_iov(client, iov, 3, errp); } /* Do a sparse read and send the structured reply to the client. @@ -2013,27 +2037,27 @@ static int coroutine_fn nbd_co_send_sparse_read(NBDClient *client, char *msg = g_strdup_printf("unable to check for holes: %s", strerror(-status)); - ret = nbd_co_send_structured_error(client, handle, -status, msg, - errp); + ret = nbd_co_send_chunk_error(client, handle, -status, msg, errp); g_free(msg); return ret; } assert(pnum && pnum <= size - progress); final = progress + pnum == size; if (status & BDRV_BLOCK_ZERO) { + NBDReply hdr; NBDStructuredReadHole chunk; struct iovec iov[] = { + {.iov_base = &hdr}, {.iov_base = &chunk, .iov_len = sizeof(chunk)}, }; - trace_nbd_co_send_structured_read_hole(handle, offset + progress, - pnum); - set_be_chunk(&chunk.h, final ? NBD_REPLY_FLAG_DONE : 0, - NBD_REPLY_TYPE_OFFSET_HOLE, - handle, sizeof(chunk) - sizeof(chunk.h)); + trace_nbd_co_send_chunk_read_hole(handle, offset + progress, pnum); + set_be_chunk(client, iov, 2, + final ? NBD_REPLY_FLAG_DONE : 0, + NBD_REPLY_TYPE_OFFSET_HOLE, handle); stq_be_p(&chunk.offset, offset + progress); stl_be_p(&chunk.length, pnum); - ret = nbd_co_send_iov(client, iov, 1, errp); + ret = nbd_co_send_iov(client, iov, 2, errp); } else { ret = blk_co_pread(exp->common.blk, offset + progress, pnum, data + progress, 0); @@ -2041,9 +2065,8 @@ static int coroutine_fn nbd_co_send_sparse_read(NBDClient *client, error_setg_errno(errp, -ret, "reading from file failed"); break; } - ret = nbd_co_send_structured_read(client, handle, offset + progress, - data + progress, pnum, final, - errp); + ret = nbd_co_send_chunk_read(client, handle, offset + progress, + data + progress, pnum, final, errp); } if (ret < 0) { @@ -2199,8 +2222,10 @@ static int coroutine_fn nbd_co_send_extents(NBDClient *client, uint64_t handle, NBDExtentArray *ea, bool last, uint32_t context_id, Error **errp) { + NBDReply hdr; NBDStructuredMeta chunk; struct iovec iov[] = { + {.iov_base = &hdr}, {.iov_base = &chunk, .iov_len = sizeof(chunk)}, {.iov_base = ea->extents, .iov_len = ea->count * sizeof(ea->extents[0])} }; @@ -2209,12 +2234,11 @@ nbd_co_send_extents(NBDClient *client, uint64_t handle, NBDExtentArray *ea, trace_nbd_co_send_extents(handle, ea->count, context_id, ea->total_length, last); - set_be_chunk(&chunk.h, last ? NBD_REPLY_FLAG_DONE : 0, - NBD_REPLY_TYPE_BLOCK_STATUS, - handle, sizeof(chunk) - sizeof(chunk.h) + iov[1].iov_len); + set_be_chunk(client, iov, 3, last ? NBD_REPLY_FLAG_DONE : 0, + NBD_REPLY_TYPE_BLOCK_STATUS, handle); stl_be_p(&chunk.context_id, context_id); - return nbd_co_send_iov(client, iov, 2, errp); + return nbd_co_send_iov(client, iov, 3, errp); } /* Get block status from the exported device and send it to the client */ @@ -2235,8 +2259,8 @@ coroutine_fn nbd_co_send_block_status(NBDClient *client, uint64_t handle, ret = blockalloc_to_extents(blk, offset, length, ea); } if (ret < 0) { - return nbd_co_send_structured_error( - client, handle, -ret, "can't get block status", errp); + return nbd_co_send_chunk_error(client, handle, -ret, + "can't get block status", errp); } return nbd_co_send_extents(client, handle, ea, last, context_id, errp); @@ -2408,8 +2432,7 @@ static coroutine_fn int nbd_send_generic_reply(NBDClient *client, Error **errp) { if (client->structured_reply && ret < 0) { - return nbd_co_send_structured_error(client, handle, -ret, error_msg, - errp); + return nbd_co_send_chunk_error(client, handle, -ret, error_msg, errp); } else { return nbd_co_send_simple_reply(client, handle, ret < 0 ? -ret : 0, NULL, 0, errp); @@ -2451,11 +2474,11 @@ static coroutine_fn int nbd_do_cmd_read(NBDClient *client, NBDRequest *request, if (client->structured_reply) { if (request->len) { - return nbd_co_send_structured_read(client, request->handle, - request->from, data, - request->len, true, errp); + return nbd_co_send_chunk_read(client, request->handle, + request->from, data, + request->len, true, errp); } else { - return nbd_co_send_structured_done(client, request->handle, errp); + return nbd_co_send_chunk_done(client, request->handle, errp); } } else { return nbd_co_send_simple_reply(client, request->handle, 0, diff --git a/nbd/trace-events b/nbd/trace-events index b7032ca277..50ca05a9e2 100644 --- a/nbd/trace-events +++ b/nbd/trace-events @@ -64,11 +64,11 @@ nbd_receive_request(uint32_t magic, uint16_t flags, uint16_t type, uint64_t from nbd_blk_aio_attached(const char *name, void *ctx) "Export %s: Attaching clients to AIO context %p" nbd_blk_aio_detach(const char *name, void *ctx) "Export %s: Detaching clients from AIO context %p" nbd_co_send_simple_reply(uint64_t handle, uint32_t error, const char *errname, int len) "Send simple reply: handle = %" PRIu64 ", error = %" PRIu32 " (%s), len = %d" -nbd_co_send_structured_done(uint64_t handle) "Send structured reply done: handle = %" PRIu64 -nbd_co_send_structured_read(uint64_t handle, uint64_t offset, void *data, size_t size) "Send structured read data reply: handle = %" PRIu64 ", offset = %" PRIu64 ", data = %p, len = %zu" -nbd_co_send_structured_read_hole(uint64_t handle, uint64_t offset, size_t size) "Send structured read hole reply: handle = %" PRIu64 ", offset = %" PRIu64 ", len = %zu" +nbd_co_send_chunk_done(uint64_t handle) "Send structured reply done: handle = %" PRIu64 +nbd_co_send_chunk_read(uint64_t handle, uint64_t offset, void *data, size_t size) "Send structured read data reply: handle = %" PRIu64 ", offset = %" PRIu64 ", data = %p, len = %zu" +nbd_co_send_chunk_read_hole(uint64_t handle, uint64_t offset, size_t size) "Send structured read hole reply: handle = %" PRIu64 ", offset = %" PRIu64 ", len = %zu" nbd_co_send_extents(uint64_t handle, unsigned int extents, uint32_t id, uint64_t length, int last) "Send block status reply: handle = %" PRIu64 ", extents = %u, context = %d (extents cover %" PRIu64 " bytes, last chunk = %d)" -nbd_co_send_structured_error(uint64_t handle, int err, const char *errname, const char *msg) "Send structured error reply: handle = %" PRIu64 ", error = %d (%s), msg = '%s'" +nbd_co_send_chunk_error(uint64_t handle, int err, const char *errname, const char *msg) "Send structured error reply: handle = %" PRIu64 ", error = %d (%s), msg = '%s'" nbd_co_receive_request_decode_type(uint64_t handle, uint16_t type, const char *name) "Decoding type: handle = %" PRIu64 ", type = %" PRIu16 " (%s)" nbd_co_receive_request_payload_received(uint64_t handle, uint32_t len) "Payload received: handle = %" PRIu64 ", len = %" PRIu32 nbd_co_receive_align_compliance(const char *op, uint64_t from, uint32_t len, uint32_t align) "client sent non-compliant unaligned %s request: from=0x%" PRIx64 ", len=0x%" PRIx32 ", align=0x%" PRIx32 |