Revision d58b0d980f0b1c27204da0e05537b606da45a07f authored by Linus Torvalds on 04 August 2016, 23:56:16 UTC, committed by Linus Torvalds on 04 August 2016, 23:56:16 UTC
Pull more btrfs updates from Chris Mason:
 "This is part two of my btrfs pull, which is some cleanups and a batch
  of fixes.

  Most of the code here is from Jeff Mahoney, making the pointers we
  pass around internally more consistent and less confusing overall.  I
  noticed a small problem right before I sent this out yesterday, so I
  fixed it up and re-tested overnight"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (40 commits)
  Btrfs: fix __MAX_CSUM_ITEMS
  btrfs: btrfs_abort_transaction, drop root parameter
  btrfs: add btrfs_trans_handle->fs_info pointer
  btrfs: btrfs_relocate_chunk pass extent_root to btrfs_end_transaction
  btrfs: convert nodesize macros to static inlines
  btrfs: introduce BTRFS_MAX_ITEM_SIZE
  btrfs: cleanup, remove prototype for btrfs_find_root_ref
  btrfs: copy_to_sk drop unused root parameter
  btrfs: simpilify btrfs_subvol_inherit_props
  btrfs: tests, use BTRFS_FS_STATE_DUMMY_FS_INFO instead of dummy root
  btrfs: tests, require fs_info for root
  btrfs: tests, move initialization into tests/
  btrfs: btrfs_test_opt and friends should take a btrfs_fs_info
  btrfs: prefix fsid to all trace events
  btrfs: plumb fs_info into btrfs_work
  btrfs: remove obsolete part of comment in statfs
  btrfs: hide test-only member under ifdef
  btrfs: Ratelimit "no csum found" info message
  btrfs: Add ratelimit to btrfs printing
  Btrfs: fix unexpected balance crash due to BUG_ON
  ...
2 parent s 3a30325 + 42049bf
Raw File
crc-t10dif.c
/*
 * T10 Data Integrity Field CRC16 calculation
 *
 * Copyright (c) 2007 Oracle Corporation.  All rights reserved.
 * Written by Martin K. Petersen <martin.petersen@oracle.com>
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2. See the file COPYING for more details.
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/crc-t10dif.h>
#include <linux/err.h>
#include <linux/init.h>
#include <crypto/hash.h>
#include <linux/static_key.h>

static struct crypto_shash *crct10dif_tfm;
static struct static_key crct10dif_fallback __read_mostly;

__u16 crc_t10dif_update(__u16 crc, const unsigned char *buffer, size_t len)
{
	struct {
		struct shash_desc shash;
		char ctx[2];
	} desc;
	int err;

	if (static_key_false(&crct10dif_fallback))
		return crc_t10dif_generic(crc, buffer, len);

	desc.shash.tfm = crct10dif_tfm;
	desc.shash.flags = 0;
	*(__u16 *)desc.ctx = crc;

	err = crypto_shash_update(&desc.shash, buffer, len);
	BUG_ON(err);

	return *(__u16 *)desc.ctx;
}
EXPORT_SYMBOL(crc_t10dif_update);

__u16 crc_t10dif(const unsigned char *buffer, size_t len)
{
	return crc_t10dif_update(0, buffer, len);
}
EXPORT_SYMBOL(crc_t10dif);

static int __init crc_t10dif_mod_init(void)
{
	crct10dif_tfm = crypto_alloc_shash("crct10dif", 0, 0);
	if (IS_ERR(crct10dif_tfm)) {
		static_key_slow_inc(&crct10dif_fallback);
		crct10dif_tfm = NULL;
	}
	return 0;
}

static void __exit crc_t10dif_mod_fini(void)
{
	crypto_free_shash(crct10dif_tfm);
}

module_init(crc_t10dif_mod_init);
module_exit(crc_t10dif_mod_fini);

MODULE_DESCRIPTION("T10 DIF CRC calculation");
MODULE_LICENSE("GPL");
MODULE_SOFTDEP("pre: crct10dif");
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