[Libguestfs] [PATCH v3 07/14] nbd/server: Refactor to pass full request around
Eric Blake
eblake at redhat.com
Mon May 15 19:53:36 UTC 2023
Part of NBD's 64-bit headers extension involves passing the client's
requested offset back as part of the reply header (one reason for this
change: converting absolute offsets stored in
NBD_REPLY_TYPE_OFFSET_DATA to relative offsets within the buffer is
easier if the absolute offset of the buffer is also available). This
is a refactoring patch to pass the full request around the reply
stack, rather than just the handle, so that later patches can then
access request->from when extended headers are active. But for this
patch, there are no semantic changes.
Signed-off-by: Eric Blake <eblake at redhat.com>
---
nbd/server.c | 117 +++++++++++++++++++++++++++------------------------
1 file changed, 61 insertions(+), 56 deletions(-)
diff --git a/nbd/server.c b/nbd/server.c
index 5812a773ace..ffab51efd26 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -1887,18 +1887,18 @@ static int coroutine_fn nbd_co_send_iov(NBDClient *client, struct iovec *iov,
}
static inline void set_be_simple_reply(NBDClient *client, struct iovec *iov,
- uint64_t error, uint64_t handle)
+ uint64_t error, NBDRequest *request)
{
NBDSimpleReply *reply = iov->iov_base;
iov->iov_len = sizeof(*reply);
stl_be_p(&reply->magic, NBD_SIMPLE_REPLY_MAGIC);
stl_be_p(&reply->error, error);
- stq_be_p(&reply->handle, handle);
+ stq_be_p(&reply->handle, request->handle);
}
static int coroutine_fn nbd_co_send_simple_reply(NBDClient *client,
- uint64_t handle,
+ NBDRequest *request,
uint32_t error,
void *data,
size_t len,
@@ -1911,16 +1911,16 @@ static int coroutine_fn nbd_co_send_simple_reply(NBDClient *client,
{.iov_base = data, .iov_len = len}
};
- trace_nbd_co_send_simple_reply(handle, nbd_err, nbd_err_lookup(nbd_err),
- len);
- set_be_simple_reply(client, &iov[0], nbd_err, handle);
+ trace_nbd_co_send_simple_reply(request->handle, nbd_err,
+ nbd_err_lookup(nbd_err), len);
+ set_be_simple_reply(client, &iov[0], nbd_err, request);
return nbd_co_send_iov(client, iov, len ? 2 : 1, errp);
}
static inline void set_be_chunk(NBDClient *client, struct iovec *iov,
uint16_t flags, uint16_t type,
- uint64_t handle, uint32_t length)
+ NBDRequest *request, uint32_t length)
{
NBDStructuredReplyChunk *chunk = iov->iov_base;
@@ -1928,12 +1928,12 @@ static inline void set_be_chunk(NBDClient *client, struct iovec *iov,
stl_be_p(&chunk->magic, NBD_STRUCTURED_REPLY_MAGIC);
stw_be_p(&chunk->flags, flags);
stw_be_p(&chunk->type, type);
- stq_be_p(&chunk->handle, handle);
+ stq_be_p(&chunk->handle, request->handle);
stl_be_p(&chunk->length, length);
}
static int coroutine_fn nbd_co_send_structured_done(NBDClient *client,
- uint64_t handle,
+ NBDRequest *request,
Error **errp)
{
NBDReply hdr;
@@ -1941,15 +1941,15 @@ static int coroutine_fn nbd_co_send_structured_done(NBDClient *client,
{.iov_base = &hdr},
};
- trace_nbd_co_send_structured_done(handle);
+ trace_nbd_co_send_structured_done(request->handle);
set_be_chunk(client, &iov[0], NBD_REPLY_FLAG_DONE,
- NBD_REPLY_TYPE_NONE, handle, 0);
+ NBD_REPLY_TYPE_NONE, request, 0);
return nbd_co_send_iov(client, iov, 1, errp);
}
static int coroutine_fn nbd_co_send_structured_read(NBDClient *client,
- uint64_t handle,
+ NBDRequest *request,
uint64_t offset,
void *data,
size_t size,
@@ -1965,16 +1965,16 @@ static int coroutine_fn nbd_co_send_structured_read(NBDClient *client,
};
assert(size);
- trace_nbd_co_send_structured_read(handle, offset, data, size);
+ trace_nbd_co_send_structured_read(request->handle, offset, data, size);
set_be_chunk(client, &iov[0], final ? NBD_REPLY_FLAG_DONE : 0,
- NBD_REPLY_TYPE_OFFSET_DATA, handle, iov[1].iov_len + size);
+ NBD_REPLY_TYPE_OFFSET_DATA, request, iov[1].iov_len + size);
stq_be_p(&chunk.offset, offset);
return nbd_co_send_iov(client, iov, 3, errp);
}
static int coroutine_fn nbd_co_send_structured_error(NBDClient *client,
- uint64_t handle,
+ NBDRequest *request,
uint32_t error,
const char *msg,
Error **errp)
@@ -1989,10 +1989,11 @@ static int coroutine_fn nbd_co_send_structured_error(NBDClient *client,
};
assert(nbd_err);
- trace_nbd_co_send_structured_error(handle, nbd_err,
+ trace_nbd_co_send_structured_error(request->handle, nbd_err,
nbd_err_lookup(nbd_err), msg ? msg : "");
set_be_chunk(client, &iov[0], NBD_REPLY_FLAG_DONE,
- NBD_REPLY_TYPE_ERROR, handle, iov[1].iov_len + iov[2].iov_len);
+ NBD_REPLY_TYPE_ERROR, request,
+ iov[1].iov_len + iov[2].iov_len);
stl_be_p(&chunk.error, nbd_err);
stw_be_p(&chunk.message_length, iov[2].iov_len);
@@ -2004,7 +2005,7 @@ static int coroutine_fn nbd_co_send_structured_error(NBDClient *client,
* reported to the client, at which point this function succeeds.
*/
static int coroutine_fn nbd_co_send_sparse_read(NBDClient *client,
- uint64_t handle,
+ NBDRequest *request,
uint64_t offset,
uint8_t *data,
size_t size,
@@ -2026,7 +2027,7 @@ 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,
+ ret = nbd_co_send_structured_error(client, request, -status, msg,
errp);
g_free(msg);
return ret;
@@ -2041,12 +2042,12 @@ static int coroutine_fn nbd_co_send_sparse_read(NBDClient *client,
{.iov_base = &chunk, .iov_len = sizeof(chunk)},
};
- trace_nbd_co_send_structured_read_hole(handle, offset + progress,
+ trace_nbd_co_send_structured_read_hole(request->handle,
+ offset + progress,
pnum);
set_be_chunk(client, &iov[0],
final ? NBD_REPLY_FLAG_DONE : 0,
- NBD_REPLY_TYPE_OFFSET_HOLE,
- handle, iov[1].iov_len);
+ NBD_REPLY_TYPE_OFFSET_HOLE, request, iov[1].iov_len);
stq_be_p(&chunk.offset, offset + progress);
stl_be_p(&chunk.length, pnum);
ret = nbd_co_send_iov(client, iov, 2, errp);
@@ -2057,7 +2058,8 @@ 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,
+ ret = nbd_co_send_structured_read(client, request,
+ offset + progress,
data + progress, pnum, final,
errp);
}
@@ -2212,7 +2214,7 @@ static int coroutine_fn blockalloc_to_extents(BlockBackend *blk,
* @last controls whether NBD_REPLY_FLAG_DONE is sent.
*/
static int coroutine_fn
-nbd_co_send_extents(NBDClient *client, uint64_t handle, NBDExtentArray *ea,
+nbd_co_send_extents(NBDClient *client, NBDRequest *request, NBDExtentArray *ea,
bool last, uint32_t context_id, Error **errp)
{
NBDReply hdr;
@@ -2225,11 +2227,11 @@ nbd_co_send_extents(NBDClient *client, uint64_t handle, NBDExtentArray *ea,
nbd_extent_array_convert_to_be(ea);
- trace_nbd_co_send_extents(handle, ea->count, context_id, ea->total_length,
- last);
+ trace_nbd_co_send_extents(request->handle, ea->count, context_id,
+ ea->total_length, last);
set_be_chunk(client, &iov[0], last ? NBD_REPLY_FLAG_DONE : 0,
NBD_REPLY_TYPE_BLOCK_STATUS,
- handle, iov[1].iov_len + iov[2].iov_len);
+ request, iov[1].iov_len + iov[2].iov_len);
stl_be_p(&chunk.context_id, context_id);
return nbd_co_send_iov(client, iov, 3, errp);
@@ -2237,7 +2239,7 @@ nbd_co_send_extents(NBDClient *client, uint64_t handle, NBDExtentArray *ea,
/* Get block status from the exported device and send it to the client */
static int
-coroutine_fn nbd_co_send_block_status(NBDClient *client, uint64_t handle,
+coroutine_fn nbd_co_send_block_status(NBDClient *client, NBDRequest *request,
BlockBackend *blk, uint64_t offset,
uint32_t length, bool dont_fragment,
bool last, uint32_t context_id,
@@ -2254,10 +2256,10 @@ coroutine_fn nbd_co_send_block_status(NBDClient *client, uint64_t handle,
}
if (ret < 0) {
return nbd_co_send_structured_error(
- client, handle, -ret, "can't get block status", errp);
+ client, request, -ret, "can't get block status", errp);
}
- return nbd_co_send_extents(client, handle, ea, last, context_id, errp);
+ return nbd_co_send_extents(client, request, ea, last, context_id, errp);
}
/* Populate @ea from a dirty bitmap. */
@@ -2292,17 +2294,20 @@ static void bitmap_to_extents(BdrvDirtyBitmap *bitmap,
bdrv_dirty_bitmap_unlock(bitmap);
}
-static int coroutine_fn nbd_co_send_bitmap(NBDClient *client, uint64_t handle,
- BdrvDirtyBitmap *bitmap, uint64_t offset,
- uint32_t length, bool dont_fragment, bool last,
- uint32_t context_id, Error **errp)
+static int coroutine_fn nbd_co_send_bitmap(NBDClient *client,
+ NBDRequest *request,
+ BdrvDirtyBitmap *bitmap,
+ uint64_t offset,
+ uint32_t length, bool dont_fragment,
+ bool last, uint32_t context_id,
+ Error **errp)
{
unsigned int nb_extents = dont_fragment ? 1 : NBD_MAX_BLOCK_STATUS_EXTENTS;
g_autoptr(NBDExtentArray) ea = nbd_extent_array_new(nb_extents);
bitmap_to_extents(bitmap, offset, length, ea);
- return nbd_co_send_extents(client, handle, ea, last, context_id, errp);
+ return nbd_co_send_extents(client, request, ea, last, context_id, errp);
}
/* nbd_co_receive_request
@@ -2443,16 +2448,16 @@ static int coroutine_fn nbd_co_receive_request(NBDRequestData *req, NBDRequest *
* Returns 0 if connection is still live, -errno on failure to talk to client
*/
static coroutine_fn int nbd_send_generic_reply(NBDClient *client,
- uint64_t handle,
+ NBDRequest *request,
int ret,
const char *error_msg,
Error **errp)
{
if (client->header_style >= NBD_HEADER_STRUCTURED && ret < 0) {
- return nbd_co_send_structured_error(client, handle, -ret, error_msg,
+ return nbd_co_send_structured_error(client, request, -ret, error_msg,
errp);
} else {
- return nbd_co_send_simple_reply(client, handle, ret < 0 ? -ret : 0,
+ return nbd_co_send_simple_reply(client, request, ret < 0 ? -ret : 0,
NULL, 0, errp);
}
}
@@ -2473,7 +2478,7 @@ static coroutine_fn int nbd_do_cmd_read(NBDClient *client, NBDRequest *request,
if (request->flags & NBD_CMD_FLAG_FUA) {
ret = blk_co_flush(exp->common.blk);
if (ret < 0) {
- return nbd_send_generic_reply(client, request->handle, ret,
+ return nbd_send_generic_reply(client, request, ret,
"flush failed", errp);
}
}
@@ -2481,26 +2486,26 @@ static coroutine_fn int nbd_do_cmd_read(NBDClient *client, NBDRequest *request,
if (client->header_style >= NBD_HEADER_STRUCTURED &&
!(request->flags & NBD_CMD_FLAG_DF) && request->len)
{
- return nbd_co_send_sparse_read(client, request->handle, request->from,
+ return nbd_co_send_sparse_read(client, request, request->from,
data, request->len, errp);
}
ret = blk_co_pread(exp->common.blk, request->from, request->len, data, 0);
if (ret < 0) {
- return nbd_send_generic_reply(client, request->handle, ret,
+ return nbd_send_generic_reply(client, request, ret,
"reading from file failed", errp);
}
if (client->header_style >= NBD_HEADER_STRUCTURED) {
if (request->len) {
- return nbd_co_send_structured_read(client, request->handle,
+ return nbd_co_send_structured_read(client, request,
request->from, data,
request->len, true, errp);
} else {
- return nbd_co_send_structured_done(client, request->handle, errp);
+ return nbd_co_send_structured_done(client, request, errp);
}
} else {
- return nbd_co_send_simple_reply(client, request->handle, 0,
+ return nbd_co_send_simple_reply(client, request, 0,
data, request->len, errp);
}
}
@@ -2524,7 +2529,7 @@ static coroutine_fn int nbd_do_cmd_cache(NBDClient *client, NBDRequest *request,
ret = blk_co_preadv(exp->common.blk, request->from, request->len,
NULL, BDRV_REQ_COPY_ON_READ | BDRV_REQ_PREFETCH);
- return nbd_send_generic_reply(client, request->handle, ret,
+ return nbd_send_generic_reply(client, request, ret,
"caching data failed", errp);
}
@@ -2556,7 +2561,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
assert(request->len <= NBD_MAX_BUFFER_SIZE);
ret = blk_co_pwrite(exp->common.blk, request->from, request->len, data,
flags);
- return nbd_send_generic_reply(client, request->handle, ret,
+ return nbd_send_generic_reply(client, request, ret,
"writing to file failed", errp);
case NBD_CMD_WRITE_ZEROES:
@@ -2572,7 +2577,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
}
ret = blk_co_pwrite_zeroes(exp->common.blk, request->from, request->len,
flags);
- return nbd_send_generic_reply(client, request->handle, ret,
+ return nbd_send_generic_reply(client, request, ret,
"writing to file failed", errp);
case NBD_CMD_DISC:
@@ -2581,7 +2586,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
case NBD_CMD_FLUSH:
ret = blk_co_flush(exp->common.blk);
- return nbd_send_generic_reply(client, request->handle, ret,
+ return nbd_send_generic_reply(client, request, ret,
"flush failed", errp);
case NBD_CMD_TRIM:
@@ -2589,12 +2594,12 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
if (ret >= 0 && request->flags & NBD_CMD_FLAG_FUA) {
ret = blk_co_flush(exp->common.blk);
}
- return nbd_send_generic_reply(client, request->handle, ret,
+ return nbd_send_generic_reply(client, request, ret,
"discard failed", errp);
case NBD_CMD_BLOCK_STATUS:
if (!request->len) {
- return nbd_send_generic_reply(client, request->handle, -EINVAL,
+ return nbd_send_generic_reply(client, request, -EINVAL,
"need non-zero length", errp);
}
assert(request->len <= UINT32_MAX);
@@ -2603,7 +2608,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
int contexts_remaining = client->export_meta.count;
if (client->export_meta.base_allocation) {
- ret = nbd_co_send_block_status(client, request->handle,
+ ret = nbd_co_send_block_status(client, request,
exp->common.blk,
request->from,
request->len, dont_fragment,
@@ -2616,7 +2621,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
}
if (client->export_meta.allocation_depth) {
- ret = nbd_co_send_block_status(client, request->handle,
+ ret = nbd_co_send_block_status(client, request,
exp->common.blk,
request->from, request->len,
dont_fragment,
@@ -2632,7 +2637,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
if (!client->export_meta.bitmaps[i]) {
continue;
}
- ret = nbd_co_send_bitmap(client, request->handle,
+ ret = nbd_co_send_bitmap(client, request,
client->exp->export_bitmaps[i],
request->from, request->len,
dont_fragment, !--contexts_remaining,
@@ -2646,7 +2651,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
return 0;
} else {
- return nbd_send_generic_reply(client, request->handle, -EINVAL,
+ return nbd_send_generic_reply(client, request, -EINVAL,
"CMD_BLOCK_STATUS not negotiated",
errp);
}
@@ -2654,7 +2659,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
default:
msg = g_strdup_printf("invalid request type (%" PRIu32 ") received",
request->type);
- ret = nbd_send_generic_reply(client, request->handle, -EINVAL, msg,
+ ret = nbd_send_generic_reply(client, request, -EINVAL, msg,
errp);
g_free(msg);
return ret;
@@ -2717,7 +2722,7 @@ static coroutine_fn void nbd_trip(void *opaque)
Error *export_err = local_err;
local_err = NULL;
- ret = nbd_send_generic_reply(client, request.handle, -EINVAL,
+ ret = nbd_send_generic_reply(client, &request, -EINVAL,
error_get_pretty(export_err), &local_err);
error_free(export_err);
} else {
--
2.40.1
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