diff options
Diffstat (limited to 'qemu/roms/ipxe/src/net/peermux.c')
| -rw-r--r-- | qemu/roms/ipxe/src/net/peermux.c | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/net/peermux.c b/qemu/roms/ipxe/src/net/peermux.c new file mode 100644 index 000000000..634c69992 --- /dev/null +++ b/qemu/roms/ipxe/src/net/peermux.c @@ -0,0 +1,387 @@ +/* + * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + * + * You can also choose to distribute this program under the terms of + * the Unmodified Binary Distribution Licence (as given in the file + * COPYING.UBDL), provided that you have satisfied its requirements. + */ + +FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); + +#include <stdlib.h> +#include <errno.h> +#include <ipxe/uri.h> +#include <ipxe/xferbuf.h> +#include <ipxe/peerblk.h> +#include <ipxe/peermux.h> + +/** @file + * + * Peer Content Caching and Retrieval (PeerDist) protocol multiplexer + * + */ + +/** + * Free PeerDist download multiplexer + * + * @v refcnt Reference count + */ +static void peermux_free ( struct refcnt *refcnt ) { + struct peerdist_multiplexer *peermux = + container_of ( refcnt, struct peerdist_multiplexer, refcnt ); + + uri_put ( peermux->uri ); + xferbuf_free ( &peermux->buffer ); + free ( peermux ); +} + +/** + * Close PeerDist download multiplexer + * + * @v peermux PeerDist download multiplexer + * @v rc Reason for close + */ +static void peermux_close ( struct peerdist_multiplexer *peermux, int rc ) { + unsigned int i; + + /* Stop block download initiation process */ + process_del ( &peermux->process ); + + /* Shut down all block downloads */ + for ( i = 0 ; i < PEERMUX_MAX_BLOCKS ; i++ ) + intf_shutdown ( &peermux->block[i].xfer, rc ); + + /* Shut down all other interfaces (which may be connected to + * the same object). + */ + intf_nullify ( &peermux->info ); /* avoid potential loops */ + intf_shutdown ( &peermux->xfer, rc ); + intf_shutdown ( &peermux->info, rc ); +} + +/** + * Receive content information + * + * @v peermux PeerDist download multiplexer + * @v iobuf I/O buffer + * @v meta Data transfer metadata + * @ret rc Return status code + */ +static int peermux_info_deliver ( struct peerdist_multiplexer *peermux, + struct io_buffer *iobuf, + struct xfer_metadata *meta ) { + int rc; + + /* Add data to buffer */ + if ( ( rc = xferbuf_deliver ( &peermux->buffer, iobuf, meta ) ) != 0 ) + goto err; + + return 0; + + err: + peermux_close ( peermux, rc ); + return rc; +} + +/** + * Close content information interface + * + * @v peermux PeerDist download multiplexer + * @v rc Reason for close + */ +static void peermux_info_close ( struct peerdist_multiplexer *peermux, int rc ){ + struct peerdist_info *info = &peermux->cache.info; + size_t len; + + /* Terminate download on error */ + if ( rc != 0 ) + goto err; + + /* Successfully closing the content information interface + * indicates that the content information has been fully + * received, and initiates the actual PeerDist download. + */ + + /* Shut down content information interface */ + intf_shutdown ( &peermux->info, rc ); + + /* Parse content information */ + if ( ( rc = peerdist_info ( info->raw.data, peermux->buffer.len, + info ) ) != 0 ) { + DBGC ( peermux, "PEERMUX %p could not parse content info: %s\n", + peermux, strerror ( rc ) ); + goto err; + } + + /* Notify recipient of total download size */ + len = ( info->trim.end - info->trim.start ); + if ( ( rc = xfer_seek ( &peermux->xfer, len ) ) != 0 ) { + DBGC ( peermux, "PEERMUX %p could not presize buffer: %s\n", + peermux, strerror ( rc ) ); + goto err; + } + xfer_seek ( &peermux->xfer, 0 ); + + /* Start block download process */ + process_add ( &peermux->process ); + + return; + + err: + peermux_close ( peermux, rc ); +} + +/** + * Initiate multiplexed block download + * + * @v peermux PeerDist download multiplexer + */ +static void peermux_step ( struct peerdist_multiplexer *peermux ) { + struct peerdist_info *info = &peermux->cache.info; + struct peerdist_info_segment *segment = &peermux->cache.segment; + struct peerdist_info_block *block = &peermux->cache.block; + struct peerdist_multiplexed_block *peermblk; + unsigned int next_segment; + unsigned int next_block; + int rc; + + /* Stop initiation process if all block downloads are busy */ + peermblk = list_first_entry ( &peermux->idle, + struct peerdist_multiplexed_block, list ); + if ( ! peermblk ) { + process_del ( &peermux->process ); + return; + } + + /* Increment block index */ + next_block = ( block->index + 1 ); + + /* Move to first/next segment, if applicable */ + if ( next_block >= segment->blocks ) { + + /* Reset block index */ + next_block = 0; + + /* Calculate segment index */ + next_segment = ( segment->info ? ( segment->index + 1 ) : 0 ); + + /* If we have finished all segments and have no + * remaining block downloads, then we are finished. + */ + if ( next_segment >= info->segments ) { + process_del ( &peermux->process ); + if ( list_empty ( &peermux->busy ) ) + peermux_close ( peermux, 0 ); + return; + } + + /* Get content information segment */ + if ( ( rc = peerdist_info_segment ( info, segment, + next_segment ) ) != 0 ) { + DBGC ( peermux, "PEERMUX %p could not get segment %d " + "information: %s\n", peermux, next_segment, + strerror ( rc ) ); + goto err; + } + } + + /* Get content information block */ + if ( ( rc = peerdist_info_block ( segment, block, next_block ) ) != 0 ){ + DBGC ( peermux, "PEERMUX %p could not get segment %d block " + "%d information: %s\n", peermux, segment->index, + next_block, strerror ( rc ) ); + goto err; + } + + /* Ignore block if it lies entirely outside the trimmed range */ + if ( block->trim.start == block->trim.end ) { + DBGC ( peermux, "PEERMUX %p skipping segment %d block %d\n", + peermux, segment->index, block->index ); + return; + } + + /* Start downloading this block */ + if ( ( rc = peerblk_open ( &peermblk->xfer, peermux->uri, + block ) ) != 0 ) { + DBGC ( peermux, "PEERMUX %p could not start download for " + "segment %d block %d: %s\n", peermux, segment->index, + block->index, strerror ( rc ) ); + goto err; + } + + /* Move to list of busy block downloads */ + list_del ( &peermblk->list ); + list_add_tail ( &peermblk->list, &peermux->busy ); + + return; + + err: + peermux_close ( peermux, rc ); +} + +/** + * Receive data from multiplexed block download + * + * @v peermblk PeerDist multiplexed block download + * @v iobuf I/O buffer + * @v meta Data transfer metadata + * @ret rc Return status code + */ +static int peermux_block_deliver ( struct peerdist_multiplexed_block *peermblk, + struct io_buffer *iobuf, + struct xfer_metadata *meta ) { + struct peerdist_multiplexer *peermux = peermblk->peermux; + + /* Sanity check: all block downloads must use absolute + * positions for all deliveries, since they run concurrently. + */ + assert ( meta->flags & XFER_FL_ABS_OFFSET ); + + /* We can't use a simple passthrough interface descriptor, + * since there are multiple block download interfaces. + */ + return xfer_deliver ( &peermux->xfer, iob_disown ( iobuf ), meta ); +} + +/** + * Get multiplexed block download underlying data transfer buffer + * + * @v peermblk PeerDist multiplexed download block + * @ret xferbuf Data transfer buffer, or NULL on error + */ +static struct xfer_buffer * +peermux_block_buffer ( struct peerdist_multiplexed_block *peermblk ) { + struct peerdist_multiplexer *peermux = peermblk->peermux; + + /* We can't use a simple passthrough interface descriptor, + * since there are multiple block download interfaces. + */ + return xfer_buffer ( &peermux->xfer ); +} + +/** + * Close multiplexed block download + * + * @v peermblk PeerDist multiplexed block download + * @v rc Reason for close + */ +static void peermux_block_close ( struct peerdist_multiplexed_block *peermblk, + int rc ) { + struct peerdist_multiplexer *peermux = peermblk->peermux; + + /* Move to list of idle downloads */ + list_del ( &peermblk->list ); + list_add_tail ( &peermblk->list, &peermux->idle ); + + /* If any error occurred, terminate the whole multiplexer */ + if ( rc != 0 ) { + peermux_close ( peermux, rc ); + return; + } + + /* Restart data transfer interface */ + intf_restart ( &peermblk->xfer, rc ); + + /* Restart block download initiation process */ + process_add ( &peermux->process ); +} + +/** Data transfer interface operations */ +static struct interface_operation peermux_xfer_operations[] = { + INTF_OP ( intf_close, struct peerdist_multiplexer *, peermux_close ), +}; + +/** Data transfer interface descriptor */ +static struct interface_descriptor peermux_xfer_desc = + INTF_DESC_PASSTHRU ( struct peerdist_multiplexer, xfer, + peermux_xfer_operations, info ); + +/** Content information interface operations */ +static struct interface_operation peermux_info_operations[] = { + INTF_OP ( xfer_deliver, struct peerdist_multiplexer *, + peermux_info_deliver ), + INTF_OP ( intf_close, struct peerdist_multiplexer *, + peermux_info_close ), +}; + +/** Content information interface descriptor */ +static struct interface_descriptor peermux_info_desc = + INTF_DESC_PASSTHRU ( struct peerdist_multiplexer, info, + peermux_info_operations, xfer ); + +/** Block download data transfer interface operations */ +static struct interface_operation peermux_block_operations[] = { + INTF_OP ( xfer_deliver, struct peerdist_multiplexed_block *, + peermux_block_deliver ), + INTF_OP ( xfer_buffer, struct peerdist_multiplexed_block *, + peermux_block_buffer ), + INTF_OP ( intf_close, struct peerdist_multiplexed_block *, + peermux_block_close ), +}; + +/** Block download data transfer interface descriptor */ +static struct interface_descriptor peermux_block_desc = + INTF_DESC ( struct peerdist_multiplexed_block, xfer, + peermux_block_operations ); + +/** Block download initiation process descriptor */ +static struct process_descriptor peermux_process_desc = + PROC_DESC ( struct peerdist_multiplexer, process, peermux_step ); + +/** + * Add PeerDist content-encoding filter + * + * @v xfer Data transfer interface + * @v info Content information interface + * @v uri Original URI + * @ret rc Return status code + */ +int peermux_filter ( struct interface *xfer, struct interface *info, + struct uri *uri ) { + struct peerdist_multiplexer *peermux; + struct peerdist_multiplexed_block *peermblk; + unsigned int i; + + /* Allocate and initialise structure */ + peermux = zalloc ( sizeof ( *peermux ) ); + if ( ! peermux ) + return -ENOMEM; + ref_init ( &peermux->refcnt, peermux_free ); + intf_init ( &peermux->xfer, &peermux_xfer_desc, &peermux->refcnt ); + intf_init ( &peermux->info, &peermux_info_desc, &peermux->refcnt ); + peermux->uri = uri_get ( uri ); + xferbuf_umalloc_init ( &peermux->buffer, + &peermux->cache.info.raw.data ); + process_init_stopped ( &peermux->process, &peermux_process_desc, + &peermux->refcnt ); + INIT_LIST_HEAD ( &peermux->busy ); + INIT_LIST_HEAD ( &peermux->idle ); + for ( i = 0 ; i < PEERMUX_MAX_BLOCKS ; i++ ) { + peermblk = &peermux->block[i]; + peermblk->peermux = peermux; + list_add_tail ( &peermblk->list, &peermux->idle ); + intf_init ( &peermblk->xfer, &peermux_block_desc, + &peermux->refcnt ); + } + + /* Attach to parent interfaces, mortalise self, and return */ + intf_plug_plug ( &peermux->xfer, xfer ); + intf_plug_plug ( &peermux->info, info ); + ref_put ( &peermux->refcnt ); + return 0; +} |