bytemark/flexnbd-c
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Formatting fixup

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This commit is contained in:
Alex Young
2013-05-01 11:02:46 +01:00
parent 151b739e8d
commit e548cc53c8
1 changed files with 113 additions and 92 deletions
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201
src/proxy.c
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@@ -2,7 +2,7 @@
#include "readwrite.h"
#ifdef PREFETCH
#include "prefetch.h"
#include "prefetch.h"
#endif
@@ -66,7 +66,7 @@ struct proxier* proxy_create(
out->upstream_fd = -1;
#ifdef PREFETCH
out->prefetch = xmalloc( sizeof( struct prefetch ) );
out->prefetch = xmalloc( sizeof( struct prefetch ) );
#endif
@@ -81,7 +81,7 @@ void proxy_destroy( struct proxier* proxy )
free( proxy->req_buf );
free( proxy->rsp_buf );
#ifdef PREFETCH
free( proxy->prefetch );
free( proxy->prefetch );
#endif
free( proxy );
@@ -243,88 +243,101 @@ int proxy_run_request_upstream( struct proxier* proxy )
unsigned char* rsp_hdr_raw = proxy->rsp_buf;
unsigned char* rsp_data = proxy->rsp_buf + NBD_REPLY_SIZE;
struct nbd_reply_raw* reply_raw = (struct nbd_reply_raw*) rsp_hdr_raw;
struct nbd_reply_raw* reply_raw = (struct nbd_reply_raw*) rsp_hdr_raw;
struct nbd_request* request = &(proxy->req_hdr);
struct nbd_request* request = &(proxy->req_hdr);
#ifdef PREFETCH
/* We only want to consider prefetching if we know we're not getting too much
* data back, if it's a read request, and if the prefetch won't try to read
* past the end of the file.
*/
int prefetching =
request->len <= PREFETCH_BUFSIZE &&
request->type == REQUEST_READ &&
(request->from + request->len * 2) <= proxy->upstream_size;
/* We only want to consider prefetching if we know we're not
* getting too much data back, if it's a read request, and if
* the prefetch won't try to read past the end of the file.
*/
int prefetching =
request->len <= PREFETCH_BUFSIZE &&
request->type == REQUEST_READ &&
(request->from + request->len * 2) <= proxy->upstream_size;
/* We pull the request out of the proxy struct, rewrite the
* request size, and write it back.
*/
if ( prefetching ) {
/* We need a malloc here because nbd_h2r_request craps
* out if passed an address on the stack
*/
struct nbd_request* rewrite_request = xmalloc( sizeof( struct nbd_request ) );
NULLCHECK( rewrite_request );
memcpy( rewrite_request, request, sizeof( struct nbd_request ) );
/* We pull the request out of the proxy struct, rewrite the
* request size, and write it back.
*/
if ( prefetching ) {
/* We need a malloc here because nbd_h2r_request craps
* out if passed an address on the stack
*/
struct nbd_request* rewrite_request =
xmalloc( sizeof( struct nbd_request ) );
NULLCHECK( rewrite_request );
memcpy( rewrite_request,
request,
sizeof( struct nbd_request ) );
rewrite_request->len *= 2;
debug( "Prefetching %d bytes", rewrite_request->len );
rewrite_request->len *= 2;
debug( "Prefetching %d bytes", rewrite_request->len );
nbd_h2r_request( rewrite_request, (struct nbd_request_raw *)proxy->req_buf );
free( rewrite_request );
}
nbd_h2r_request( rewrite_request,
(struct nbd_request_raw *)proxy->req_buf );
free( rewrite_request );
}
#endif
struct nbd_reply* reply = &(proxy->rsp_hdr);
struct nbd_reply* reply = &(proxy->rsp_hdr);
size_t rsp_buf_size;
#ifdef PREFETCH
if ( request->type == REQUEST_READ ){
/* See if we can respond with what's in our prefetch
* cache
*/
if( proxy->prefetch->is_full &&
request->from == proxy->prefetch->from &&
request->len == proxy->prefetch->len ) {
/* HUZZAH! A match! */
debug( "Prefetch hit!" );
if ( request->type == REQUEST_READ ){
/* See if we can respond with what's in our prefetch
* cache
*/
if( proxy->prefetch->is_full &&
request->from == proxy->prefetch->from &&
request->len == proxy->prefetch->len ) {
/* HUZZAH! A match! */
debug( "Prefetch hit!" );
/* First build a reply header */
struct nbd_reply prefetch_reply = {REPLY_MAGIC, 0, "01234567"};
memcpy( &(prefetch_reply.handle), request->handle, 8 );
/* First build a reply header */
struct nbd_reply prefetch_reply =
{REPLY_MAGIC, 0, "01234567"};
memcpy( &(prefetch_reply.handle), request->handle, 8 );
/* now copy it into the response */
nbd_h2r_reply( &prefetch_reply, reply_raw );
/* now copy it into the response */
nbd_h2r_reply( &prefetch_reply, reply_raw );
/* and the data */
memcpy( rsp_data, proxy->prefetch->buffer, proxy->prefetch->len );
/* and the data */
memcpy( rsp_data,
proxy->prefetch->buffer,
proxy->prefetch->len );
proxy->rsp_buf_size = NBD_REPLY_SIZE + proxy->prefetch->len;
proxy->rsp_buf_size =
NBD_REPLY_SIZE + proxy->prefetch->len;
/* return early, our work here is done */
return 1;
}
}
else {
/* Safety catch. If we're sending a write request, we
* blow away the cache. This is very pessimistic, but
* it's simpler (and therefore safer) than working out
* whether we can keep it or not.
*/
debug( "Blowing away prefetch cache on type %d request.", request->type );
proxy->prefetch->is_full = 0;
}
/* return early, our work here is done */
return 1;
}
}
else {
/* Safety catch. If we're sending a write request, we
* blow away the cache. This is very pessimistic, but
* it's simpler (and therefore safer) than working out
* whether we can keep it or not.
*/
debug("Blowing away prefetch cache on type %d request.",
request->type);
proxy->prefetch->is_full = 0;
}
#endif
if ( writeloop( proxy->upstream_fd, proxy->req_buf, proxy->req_buf_size ) == -1 ) {
if ( -1 == writeloop( proxy->upstream_fd,
proxy->req_buf,
proxy->req_buf_size ) ) {
warn( "Failed to send request to upstream" );
goto disconnect;
goto disconnect;
}
if ( readloop( proxy->upstream_fd, rsp_hdr_raw, NBD_REPLY_SIZE ) == -1 ) {
if ( -1 == readloop( proxy->upstream_fd,
rsp_hdr_raw,
NBD_REPLY_SIZE ) ) {
debug( "Failed to get reply header from upstream" );
goto disconnect;
goto disconnect;
}
nbd_r2h_reply( reply_raw, reply );
@@ -332,51 +345,59 @@ int proxy_run_request_upstream( struct proxier* proxy )
if ( reply->magic != REPLY_MAGIC ) {
debug( "Reply magic is incorrect" );
goto disconnect;
goto disconnect;
}
debug( "NBD reply received from upstream. Response code: %"PRIu32, reply->error );
debug("NBD reply received from upstream. Response code: %"PRIu32,
reply->error );
if ( reply->error != 0 ) {
warn( "NBD error returned from upstream: %"PRIu32, reply->error );
warn( "NBD error returned from upstream: %"PRIu32,
reply->error );
}
if ( reply->error == 0 && request->type == REQUEST_READ ) {
if ( reply->error == 0 && request->type == REQUEST_READ ) {
#ifdef PREFETCH
if (readloop( proxy->upstream_fd, rsp_data, request->len ) == -1 ) {
debug( "Failed to get reply data from upstream" );
goto disconnect;
}
if ( -1 == readloop( proxy->upstream_fd,
rsp_data,
request->len ) ) {
debug( "Failed to get reply data from upstream" );
goto disconnect;
}
if ( prefetching ) {
if ( readloop( proxy->upstream_fd, &(proxy->prefetch->buffer), request->len ) == -1 ) {
debug( "Failed to get prefetch reply data from upstream" );
goto disconnect;
}
proxy->prefetch->from = request->from + request->len;
proxy->prefetch->len = request->len;
proxy->prefetch->is_full = 1;
}
if ( prefetching ) {
if ( -1 == readloop( proxy->upstream_fd,
&(proxy->prefetch->buffer),
request->len ) ) {
debug( "Failed to get prefetch reply data "
"from upstream" );
goto disconnect;
}
proxy->prefetch->from = request->from + request->len;
proxy->prefetch->len = request->len;
proxy->prefetch->is_full = 1;
}
#else
if (readloop( proxy->upstream_fd, rsp_data, request->len ) == -1 ) {
debug( "Failed to get reply data from upstream" );
goto disconnect;
}
if ( -1 == readloop( proxy->upstream_fd,
rsp_data,
request->len ) ) {
debug( "Failed to get reply data from upstream" );
goto disconnect;
}
#endif
rsp_buf_size += request->len;
}
rsp_buf_size += request->len;
}
proxy->rsp_buf_size = rsp_buf_size;
return 1;
disconnect:
proxy_disconnect_from_upstream( proxy );
proxy_disconnect_from_upstream( proxy );
#ifdef PREFETCH
proxy->prefetch->is_full = 0;
proxy->prefetch->is_full = 0;
#endif
return 0;
return 0;
}
/* Write an NBD reply back downstream. Return 0 on failure, 1 on success. */