From 68dd826b860244856d539b06a38feecf523744fd Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Fri, 18 May 2007 14:45:16 +0000 Subject: Add alloc_iob() and free_iob(). (Direct search-and-replace equivalents for alloc_pkb() and free_pkb(), which will be retired in due course). --- src/core/iobuf.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 src/core/iobuf.c (limited to 'src/core/iobuf.c') diff --git a/src/core/iobuf.c b/src/core/iobuf.c new file mode 100644 index 00000000..d04ede51 --- /dev/null +++ b/src/core/iobuf.c @@ -0,0 +1,74 @@ +/* + * Copyright (C) 2006 Michael Brown . + * + * 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 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., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include +#include +#include + +/** @file + * + * I/O buffers + * + */ + +/** + * Allocate I/O buffer + * + * @v len Required length of buffer + * @ret iobuf I/O buffer, or NULL if none available + * + * The I/O buffer will be physically aligned to a multiple of + * @c IOBUF_SIZE. + */ +struct io_buffer * alloc_iob ( size_t len ) { + struct io_buffer *iobuf = NULL; + void *data; + + /* Pad to minimum length */ + if ( len < IOB_ZLEN ) + len = IOB_ZLEN; + + /* Align buffer length */ + len = ( len + __alignof__( *iobuf ) - 1 ) & + ~( __alignof__( *iobuf ) - 1 ); + + /* Allocate memory for buffer plus descriptor */ + data = malloc_dma ( len + sizeof ( *iobuf ), IOB_ALIGN ); + if ( ! data ) + return NULL; + + iobuf = ( struct io_buffer * ) ( data + len ); + iobuf->head = iobuf->data = iobuf->tail = data; + iobuf->end = iobuf; + return iobuf; +} + +/** + * Free I/O buffer + * + * @v iobuf I/O buffer + */ +void free_iob ( struct io_buffer *iobuf ) { + if ( iobuf ) { + assert ( iobuf->head <= iobuf->data ); + assert ( iobuf->data <= iobuf->tail ); + assert ( iobuf->tail <= iobuf->end ); + free_dma ( iobuf->head, + ( iobuf->end - iobuf->head ) + sizeof ( *iobuf ) ); + } +} -- cgit