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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2019 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "scrub/array.h"
#include "scrub/blob.h"
/*
* XFS Blob Storage
* ================
* Stores and retrieves blobs using a list. Objects are appended to
* the list and the pointer is returned as a magic cookie for retrieval.
*/
#define XB_KEY_MAGIC 0xABAADDAD
struct xb_key {
struct list_head list;
uint32_t magic;
uint32_t size;
/* blob comes after here */
} __packed;
#define XB_KEY_SIZE(sz) (sizeof(struct xb_key) + (sz))
/* Initialize a blob storage object. */
struct xblob *
xblob_init(void)
{
struct xblob *blob;
int error;
error = -ENOMEM;
blob = kmem_alloc(sizeof(struct xblob), KM_NOFS | KM_MAYFAIL);
if (!blob)
return ERR_PTR(error);
INIT_LIST_HEAD(&blob->list);
return blob;
}
/* Destroy a blob storage object. */
void
xblob_destroy(
struct xblob *blob)
{
struct xb_key *key, *n;
list_for_each_entry_safe(key, n, &blob->list, list) {
list_del(&key->list);
kmem_free(key);
}
kmem_free(blob);
}
/* Retrieve a blob. */
int
xblob_get(
struct xblob *blob,
xblob_cookie cookie,
void *ptr,
uint32_t size)
{
struct xb_key *key = (struct xb_key *)cookie;
if (key->magic != XB_KEY_MAGIC) {
ASSERT(0);
return -ENODATA;
}
if (size < key->size) {
ASSERT(0);
return -EFBIG;
}
memcpy(ptr, key + 1, key->size);
return 0;
}
/* Store a blob. */
int
xblob_put(
struct xblob *blob,
xblob_cookie *cookie,
void *ptr,
uint32_t size)
{
struct xb_key *key;
key = kmem_alloc(XB_KEY_SIZE(size), KM_NOFS | KM_MAYFAIL);
if (!key)
return -ENOMEM;
INIT_LIST_HEAD(&key->list);
list_add_tail(&key->list, &blob->list);
key->magic = XB_KEY_MAGIC;
key->size = size;
memcpy(key + 1, ptr, size);
*cookie = (xblob_cookie)key;
return 0;
}
/* Free a blob. */
int
xblob_free(
struct xblob *blob,
xblob_cookie cookie)
{
struct xb_key *key = (struct xb_key *)cookie;
if (key->magic != XB_KEY_MAGIC) {
ASSERT(0);
return -ENODATA;
}
key->magic = 0;
list_del(&key->list);
kmem_free(key);
return 0;
}
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