cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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fc_frame.c (1800B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Copyright(c) 2007 Intel Corporation. All rights reserved.
      4 *
      5 * Maintained at www.Open-FCoE.org
      6 */
      7
      8/*
      9 * Frame allocation.
     10 */
     11#include <linux/module.h>
     12#include <linux/kernel.h>
     13#include <linux/skbuff.h>
     14#include <linux/crc32.h>
     15#include <linux/gfp.h>
     16
     17#include <scsi/fc_frame.h>
     18
     19/*
     20 * Check the CRC in a frame.
     21 */
     22u32 fc_frame_crc_check(struct fc_frame *fp)
     23{
     24	u32 crc;
     25	u32 error;
     26	const u8 *bp;
     27	unsigned int len;
     28
     29	WARN_ON(!fc_frame_is_linear(fp));
     30	fr_flags(fp) &= ~FCPHF_CRC_UNCHECKED;
     31	len = (fr_len(fp) + 3) & ~3;	/* round up length to include fill */
     32	bp = (const u8 *) fr_hdr(fp);
     33	crc = ~crc32(~0, bp, len);
     34	error = crc ^ fr_crc(fp);
     35	return error;
     36}
     37EXPORT_SYMBOL(fc_frame_crc_check);
     38
     39/*
     40 * Allocate a frame intended to be sent.
     41 * Get an sk_buff for the frame and set the length.
     42 */
     43struct fc_frame *_fc_frame_alloc(size_t len)
     44{
     45	struct fc_frame *fp;
     46	struct sk_buff *skb;
     47
     48	WARN_ON((len % sizeof(u32)) != 0);
     49	len += sizeof(struct fc_frame_header);
     50	skb = alloc_skb_fclone(len + FC_FRAME_HEADROOM + FC_FRAME_TAILROOM +
     51			       NET_SKB_PAD, GFP_ATOMIC);
     52	if (!skb)
     53		return NULL;
     54	skb_reserve(skb, NET_SKB_PAD + FC_FRAME_HEADROOM);
     55	fp = (struct fc_frame *) skb;
     56	fc_frame_init(fp);
     57	skb_put(skb, len);
     58	return fp;
     59}
     60EXPORT_SYMBOL(_fc_frame_alloc);
     61
     62struct fc_frame *fc_frame_alloc_fill(struct fc_lport *lp, size_t payload_len)
     63{
     64	struct fc_frame *fp;
     65	size_t fill;
     66
     67	fill = payload_len % 4;
     68	if (fill != 0)
     69		fill = 4 - fill;
     70	fp = _fc_frame_alloc(payload_len + fill);
     71	if (fp) {
     72		memset((char *) fr_hdr(fp) + payload_len, 0, fill);
     73		/* trim is OK, we just allocated it so there are no fragments */
     74		skb_trim(fp_skb(fp),
     75			 payload_len + sizeof(struct fc_frame_header));
     76	}
     77	return fp;
     78}
     79EXPORT_SYMBOL(fc_frame_alloc_fill);