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kernel-fxtec-pro1x/drivers/crypto/s5p-sss.c
Jingoo Han 5c22ba6619 crypto: s5p-sss - Use devm_clk_get() 
Use devm_clk_get() rather than clk_get() to make cleanup paths
more simple.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-01-20 10:16:44 +11:00

689 lines
18 KiB
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/*
* Cryptographic API.
*
* Support for Samsung S5PV210 HW acceleration.
*
* Copyright (C) 2011 NetUP Inc. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
*/
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/crypto.h>
#include <linux/interrupt.h>
#include <crypto/algapi.h>
#include <crypto/aes.h>
#include <crypto/ctr.h>
#include <plat/cpu.h>
#include <mach/dma.h>
#define _SBF(s, v) ((v) << (s))
#define _BIT(b) _SBF(b, 1)
/* Feed control registers */
#define SSS_REG_FCINTSTAT 0x0000
#define SSS_FCINTSTAT_BRDMAINT _BIT(3)
#define SSS_FCINTSTAT_BTDMAINT _BIT(2)
#define SSS_FCINTSTAT_HRDMAINT _BIT(1)
#define SSS_FCINTSTAT_PKDMAINT _BIT(0)
#define SSS_REG_FCINTENSET 0x0004
#define SSS_FCINTENSET_BRDMAINTENSET _BIT(3)
#define SSS_FCINTENSET_BTDMAINTENSET _BIT(2)
#define SSS_FCINTENSET_HRDMAINTENSET _BIT(1)
#define SSS_FCINTENSET_PKDMAINTENSET _BIT(0)
#define SSS_REG_FCINTENCLR 0x0008
#define SSS_FCINTENCLR_BRDMAINTENCLR _BIT(3)
#define SSS_FCINTENCLR_BTDMAINTENCLR _BIT(2)
#define SSS_FCINTENCLR_HRDMAINTENCLR _BIT(1)
#define SSS_FCINTENCLR_PKDMAINTENCLR _BIT(0)
#define SSS_REG_FCINTPEND 0x000C
#define SSS_FCINTPEND_BRDMAINTP _BIT(3)
#define SSS_FCINTPEND_BTDMAINTP _BIT(2)
#define SSS_FCINTPEND_HRDMAINTP _BIT(1)
#define SSS_FCINTPEND_PKDMAINTP _BIT(0)
#define SSS_REG_FCFIFOSTAT 0x0010
#define SSS_FCFIFOSTAT_BRFIFOFUL _BIT(7)
#define SSS_FCFIFOSTAT_BRFIFOEMP _BIT(6)
#define SSS_FCFIFOSTAT_BTFIFOFUL _BIT(5)
#define SSS_FCFIFOSTAT_BTFIFOEMP _BIT(4)
#define SSS_FCFIFOSTAT_HRFIFOFUL _BIT(3)
#define SSS_FCFIFOSTAT_HRFIFOEMP _BIT(2)
#define SSS_FCFIFOSTAT_PKFIFOFUL _BIT(1)
#define SSS_FCFIFOSTAT_PKFIFOEMP _BIT(0)
#define SSS_REG_FCFIFOCTRL 0x0014
#define SSS_FCFIFOCTRL_DESSEL _BIT(2)
#define SSS_HASHIN_INDEPENDENT _SBF(0, 0x00)
#define SSS_HASHIN_CIPHER_INPUT _SBF(0, 0x01)
#define SSS_HASHIN_CIPHER_OUTPUT _SBF(0, 0x02)
#define SSS_REG_FCBRDMAS 0x0020
#define SSS_REG_FCBRDMAL 0x0024
#define SSS_REG_FCBRDMAC 0x0028
#define SSS_FCBRDMAC_BYTESWAP _BIT(1)
#define SSS_FCBRDMAC_FLUSH _BIT(0)
#define SSS_REG_FCBTDMAS 0x0030
#define SSS_REG_FCBTDMAL 0x0034
#define SSS_REG_FCBTDMAC 0x0038
#define SSS_FCBTDMAC_BYTESWAP _BIT(1)
#define SSS_FCBTDMAC_FLUSH _BIT(0)
#define SSS_REG_FCHRDMAS 0x0040
#define SSS_REG_FCHRDMAL 0x0044
#define SSS_REG_FCHRDMAC 0x0048
#define SSS_FCHRDMAC_BYTESWAP _BIT(1)
#define SSS_FCHRDMAC_FLUSH _BIT(0)
#define SSS_REG_FCPKDMAS 0x0050
#define SSS_REG_FCPKDMAL 0x0054
#define SSS_REG_FCPKDMAC 0x0058
#define SSS_FCPKDMAC_BYTESWAP _BIT(3)
#define SSS_FCPKDMAC_DESCEND _BIT(2)
#define SSS_FCPKDMAC_TRANSMIT _BIT(1)
#define SSS_FCPKDMAC_FLUSH _BIT(0)
#define SSS_REG_FCPKDMAO 0x005C
/* AES registers */
#define SSS_REG_AES_CONTROL 0x4000
#define SSS_AES_BYTESWAP_DI _BIT(11)
#define SSS_AES_BYTESWAP_DO _BIT(10)
#define SSS_AES_BYTESWAP_IV _BIT(9)
#define SSS_AES_BYTESWAP_CNT _BIT(8)
#define SSS_AES_BYTESWAP_KEY _BIT(7)
#define SSS_AES_KEY_CHANGE_MODE _BIT(6)
#define SSS_AES_KEY_SIZE_128 _SBF(4, 0x00)
#define SSS_AES_KEY_SIZE_192 _SBF(4, 0x01)
#define SSS_AES_KEY_SIZE_256 _SBF(4, 0x02)
#define SSS_AES_FIFO_MODE _BIT(3)
#define SSS_AES_CHAIN_MODE_ECB _SBF(1, 0x00)
#define SSS_AES_CHAIN_MODE_CBC _SBF(1, 0x01)
#define SSS_AES_CHAIN_MODE_CTR _SBF(1, 0x02)
#define SSS_AES_MODE_DECRYPT _BIT(0)
#define SSS_REG_AES_STATUS 0x4004
#define SSS_AES_BUSY _BIT(2)
#define SSS_AES_INPUT_READY _BIT(1)
#define SSS_AES_OUTPUT_READY _BIT(0)
#define SSS_REG_AES_IN_DATA(s) (0x4010 + (s << 2))
#define SSS_REG_AES_OUT_DATA(s) (0x4020 + (s << 2))
#define SSS_REG_AES_IV_DATA(s) (0x4030 + (s << 2))
#define SSS_REG_AES_CNT_DATA(s) (0x4040 + (s << 2))
#define SSS_REG_AES_KEY_DATA(s) (0x4080 + (s << 2))
#define SSS_REG(dev, reg) ((dev)->ioaddr + (SSS_REG_##reg))
#define SSS_READ(dev, reg) __raw_readl(SSS_REG(dev, reg))
#define SSS_WRITE(dev, reg, val) __raw_writel((val), SSS_REG(dev, reg))
/* HW engine modes */
#define FLAGS_AES_DECRYPT _BIT(0)
#define FLAGS_AES_MODE_MASK _SBF(1, 0x03)
#define FLAGS_AES_CBC _SBF(1, 0x01)
#define FLAGS_AES_CTR _SBF(1, 0x02)
#define AES_KEY_LEN 16
#define CRYPTO_QUEUE_LEN 1
struct s5p_aes_reqctx {
unsigned long mode;
};
struct s5p_aes_ctx {
struct s5p_aes_dev *dev;
uint8_t aes_key[AES_MAX_KEY_SIZE];
uint8_t nonce[CTR_RFC3686_NONCE_SIZE];
int keylen;
};
struct s5p_aes_dev {
struct device *dev;
struct clk *clk;
void __iomem *ioaddr;
int irq_hash;
int irq_fc;
struct ablkcipher_request *req;
struct s5p_aes_ctx *ctx;
struct scatterlist *sg_src;
struct scatterlist *sg_dst;
struct tasklet_struct tasklet;
struct crypto_queue queue;
bool busy;
spinlock_t lock;
};
static struct s5p_aes_dev *s5p_dev;
static void s5p_set_dma_indata(struct s5p_aes_dev *dev, struct scatterlist *sg)
{
SSS_WRITE(dev, FCBRDMAS, sg_dma_address(sg));
SSS_WRITE(dev, FCBRDMAL, sg_dma_len(sg));
}
static void s5p_set_dma_outdata(struct s5p_aes_dev *dev, struct scatterlist *sg)
{
SSS_WRITE(dev, FCBTDMAS, sg_dma_address(sg));
SSS_WRITE(dev, FCBTDMAL, sg_dma_len(sg));
}
static void s5p_aes_complete(struct s5p_aes_dev *dev, int err)
{
/* holding a lock outside */
dev->req->base.complete(&dev->req->base, err);
dev->busy = false;
}
static void s5p_unset_outdata(struct s5p_aes_dev *dev)
{
dma_unmap_sg(dev->dev, dev->sg_dst, 1, DMA_FROM_DEVICE);
}
static void s5p_unset_indata(struct s5p_aes_dev *dev)
{
dma_unmap_sg(dev->dev, dev->sg_src, 1, DMA_TO_DEVICE);
}
static int s5p_set_outdata(struct s5p_aes_dev *dev, struct scatterlist *sg)
{
int err;
if (!IS_ALIGNED(sg_dma_len(sg), AES_BLOCK_SIZE)) {
err = -EINVAL;
goto exit;
}
if (!sg_dma_len(sg)) {
err = -EINVAL;
goto exit;
}
err = dma_map_sg(dev->dev, sg, 1, DMA_FROM_DEVICE);
if (!err) {
err = -ENOMEM;
goto exit;
}
dev->sg_dst = sg;
err = 0;
exit:
return err;
}
static int s5p_set_indata(struct s5p_aes_dev *dev, struct scatterlist *sg)
{
int err;
if (!IS_ALIGNED(sg_dma_len(sg), AES_BLOCK_SIZE)) {
err = -EINVAL;
goto exit;
}
if (!sg_dma_len(sg)) {
err = -EINVAL;
goto exit;
}
err = dma_map_sg(dev->dev, sg, 1, DMA_TO_DEVICE);
if (!err) {
err = -ENOMEM;
goto exit;
}
dev->sg_src = sg;
err = 0;
exit:
return err;
}
static void s5p_aes_tx(struct s5p_aes_dev *dev)
{
int err = 0;
s5p_unset_outdata(dev);
if (!sg_is_last(dev->sg_dst)) {
err = s5p_set_outdata(dev, sg_next(dev->sg_dst));
if (err) {
s5p_aes_complete(dev, err);
return;
}
s5p_set_dma_outdata(dev, dev->sg_dst);
} else
s5p_aes_complete(dev, err);
}
static void s5p_aes_rx(struct s5p_aes_dev *dev)
{
int err;
s5p_unset_indata(dev);
if (!sg_is_last(dev->sg_src)) {
err = s5p_set_indata(dev, sg_next(dev->sg_src));
if (err) {
s5p_aes_complete(dev, err);
return;
}
s5p_set_dma_indata(dev, dev->sg_src);
}
}
static irqreturn_t s5p_aes_interrupt(int irq, void *dev_id)
{
struct platform_device *pdev = dev_id;
struct s5p_aes_dev *dev = platform_get_drvdata(pdev);
uint32_t status;
unsigned long flags;
spin_lock_irqsave(&dev->lock, flags);
if (irq == dev->irq_fc) {
status = SSS_READ(dev, FCINTSTAT);
if (status & SSS_FCINTSTAT_BRDMAINT)
s5p_aes_rx(dev);
if (status & SSS_FCINTSTAT_BTDMAINT)
s5p_aes_tx(dev);
SSS_WRITE(dev, FCINTPEND, status);
}
spin_unlock_irqrestore(&dev->lock, flags);
return IRQ_HANDLED;
}
static void s5p_set_aes(struct s5p_aes_dev *dev,
uint8_t *key, uint8_t *iv, unsigned int keylen)
{
void __iomem *keystart;
memcpy(dev->ioaddr + SSS_REG_AES_IV_DATA(0), iv, 0x10);
if (keylen == AES_KEYSIZE_256)
keystart = dev->ioaddr + SSS_REG_AES_KEY_DATA(0);
else if (keylen == AES_KEYSIZE_192)
keystart = dev->ioaddr + SSS_REG_AES_KEY_DATA(2);
else
keystart = dev->ioaddr + SSS_REG_AES_KEY_DATA(4);
memcpy(keystart, key, keylen);
}
static void s5p_aes_crypt_start(struct s5p_aes_dev *dev, unsigned long mode)
{
struct ablkcipher_request *req = dev->req;
uint32_t aes_control;
int err;
unsigned long flags;
aes_control = SSS_AES_KEY_CHANGE_MODE;
if (mode & FLAGS_AES_DECRYPT)
aes_control |= SSS_AES_MODE_DECRYPT;
if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CBC)
aes_control |= SSS_AES_CHAIN_MODE_CBC;
else if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CTR)
aes_control |= SSS_AES_CHAIN_MODE_CTR;
if (dev->ctx->keylen == AES_KEYSIZE_192)
aes_control |= SSS_AES_KEY_SIZE_192;
else if (dev->ctx->keylen == AES_KEYSIZE_256)
aes_control |= SSS_AES_KEY_SIZE_256;
aes_control |= SSS_AES_FIFO_MODE;
/* as a variant it is possible to use byte swapping on DMA side */
aes_control |= SSS_AES_BYTESWAP_DI
| SSS_AES_BYTESWAP_DO
| SSS_AES_BYTESWAP_IV
| SSS_AES_BYTESWAP_KEY
| SSS_AES_BYTESWAP_CNT;
spin_lock_irqsave(&dev->lock, flags);
SSS_WRITE(dev, FCINTENCLR,
SSS_FCINTENCLR_BTDMAINTENCLR | SSS_FCINTENCLR_BRDMAINTENCLR);
SSS_WRITE(dev, FCFIFOCTRL, 0x00);
err = s5p_set_indata(dev, req->src);
if (err)
goto indata_error;
err = s5p_set_outdata(dev, req->dst);
if (err)
goto outdata_error;
SSS_WRITE(dev, AES_CONTROL, aes_control);
s5p_set_aes(dev, dev->ctx->aes_key, req->info, dev->ctx->keylen);
s5p_set_dma_indata(dev, req->src);
s5p_set_dma_outdata(dev, req->dst);
SSS_WRITE(dev, FCINTENSET,
SSS_FCINTENSET_BTDMAINTENSET | SSS_FCINTENSET_BRDMAINTENSET);
spin_unlock_irqrestore(&dev->lock, flags);
return;
outdata_error:
s5p_unset_indata(dev);
indata_error:
s5p_aes_complete(dev, err);
spin_unlock_irqrestore(&dev->lock, flags);
}
static void s5p_tasklet_cb(unsigned long data)
{
struct s5p_aes_dev *dev = (struct s5p_aes_dev *)data;
struct crypto_async_request *async_req, *backlog;
struct s5p_aes_reqctx *reqctx;
unsigned long flags;
spin_lock_irqsave(&dev->lock, flags);
backlog = crypto_get_backlog(&dev->queue);
async_req = crypto_dequeue_request(&dev->queue);
spin_unlock_irqrestore(&dev->lock, flags);
if (!async_req)
return;
if (backlog)
backlog->complete(backlog, -EINPROGRESS);
dev->req = ablkcipher_request_cast(async_req);
dev->ctx = crypto_tfm_ctx(dev->req->base.tfm);
reqctx = ablkcipher_request_ctx(dev->req);
s5p_aes_crypt_start(dev, reqctx->mode);
}
static int s5p_aes_handle_req(struct s5p_aes_dev *dev,
struct ablkcipher_request *req)
{
unsigned long flags;
int err;
spin_lock_irqsave(&dev->lock, flags);
if (dev->busy) {
err = -EAGAIN;
spin_unlock_irqrestore(&dev->lock, flags);
goto exit;
}
dev->busy = true;
err = ablkcipher_enqueue_request(&dev->queue, req);
spin_unlock_irqrestore(&dev->lock, flags);
tasklet_schedule(&dev->tasklet);
exit:
return err;
}
static int s5p_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
{
struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
struct s5p_aes_ctx *ctx = crypto_ablkcipher_ctx(tfm);
struct s5p_aes_reqctx *reqctx = ablkcipher_request_ctx(req);
struct s5p_aes_dev *dev = ctx->dev;
if (!IS_ALIGNED(req->nbytes, AES_BLOCK_SIZE)) {
pr_err("request size is not exact amount of AES blocks\n");
return -EINVAL;
}
reqctx->mode = mode;
return s5p_aes_handle_req(dev, req);
}
static int s5p_aes_setkey(struct crypto_ablkcipher *cipher,
const uint8_t *key, unsigned int keylen)
{
struct crypto_tfm *tfm = crypto_ablkcipher_tfm(cipher);
struct s5p_aes_ctx *ctx = crypto_tfm_ctx(tfm);
if (keylen != AES_KEYSIZE_128 &&
keylen != AES_KEYSIZE_192 &&
keylen != AES_KEYSIZE_256)
return -EINVAL;
memcpy(ctx->aes_key, key, keylen);
ctx->keylen = keylen;
return 0;
}
static int s5p_aes_ecb_encrypt(struct ablkcipher_request *req)
{
return s5p_aes_crypt(req, 0);
}
static int s5p_aes_ecb_decrypt(struct ablkcipher_request *req)
{
return s5p_aes_crypt(req, FLAGS_AES_DECRYPT);
}
static int s5p_aes_cbc_encrypt(struct ablkcipher_request *req)
{
return s5p_aes_crypt(req, FLAGS_AES_CBC);
}
static int s5p_aes_cbc_decrypt(struct ablkcipher_request *req)
{
return s5p_aes_crypt(req, FLAGS_AES_DECRYPT | FLAGS_AES_CBC);
}
static int s5p_aes_cra_init(struct crypto_tfm *tfm)
{
struct s5p_aes_ctx *ctx = crypto_tfm_ctx(tfm);
ctx->dev = s5p_dev;
tfm->crt_ablkcipher.reqsize = sizeof(struct s5p_aes_reqctx);
return 0;
}
static struct crypto_alg algs[] = {
{
.cra_name = "ecb(aes)",
.cra_driver_name = "ecb-aes-s5p",
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
CRYPTO_ALG_ASYNC |
CRYPTO_ALG_KERN_DRIVER_ONLY,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s5p_aes_ctx),
.cra_alignmask = 0x0f,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = s5p_aes_cra_init,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.setkey = s5p_aes_setkey,
.encrypt = s5p_aes_ecb_encrypt,
.decrypt = s5p_aes_ecb_decrypt,
}
},
{
.cra_name = "cbc(aes)",
.cra_driver_name = "cbc-aes-s5p",
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
CRYPTO_ALG_ASYNC |
CRYPTO_ALG_KERN_DRIVER_ONLY,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s5p_aes_ctx),
.cra_alignmask = 0x0f,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = s5p_aes_cra_init,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = s5p_aes_setkey,
.encrypt = s5p_aes_cbc_encrypt,
.decrypt = s5p_aes_cbc_decrypt,
}
},
};
static int s5p_aes_probe(struct platform_device *pdev)
{
int i, j, err = -ENODEV;
struct s5p_aes_dev *pdata;
struct device *dev = &pdev->dev;
struct resource *res;
if (s5p_dev)
return -EEXIST;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return -ENOMEM;
if (!devm_request_mem_region(dev, res->start,
resource_size(res), pdev->name))
return -EBUSY;
pdata->clk = devm_clk_get(dev, "secss");
if (IS_ERR(pdata->clk)) {
dev_err(dev, "failed to find secss clock source\n");
return -ENOENT;
}
clk_enable(pdata->clk);
spin_lock_init(&pdata->lock);
pdata->ioaddr = devm_ioremap(dev, res->start,
resource_size(res));
pdata->irq_hash = platform_get_irq_byname(pdev, "hash");
if (pdata->irq_hash < 0) {
err = pdata->irq_hash;
dev_warn(dev, "hash interrupt is not available.\n");
goto err_irq;
}
err = devm_request_irq(dev, pdata->irq_hash, s5p_aes_interrupt,
IRQF_SHARED, pdev->name, pdev);
if (err < 0) {
dev_warn(dev, "hash interrupt is not available.\n");
goto err_irq;
}
pdata->irq_fc = platform_get_irq_byname(pdev, "feed control");
if (pdata->irq_fc < 0) {
err = pdata->irq_fc;
dev_warn(dev, "feed control interrupt is not available.\n");
goto err_irq;
}
err = devm_request_irq(dev, pdata->irq_fc, s5p_aes_interrupt,
IRQF_SHARED, pdev->name, pdev);
if (err < 0) {
dev_warn(dev, "feed control interrupt is not available.\n");
goto err_irq;
}
pdata->dev = dev;
platform_set_drvdata(pdev, pdata);
s5p_dev = pdata;
tasklet_init(&pdata->tasklet, s5p_tasklet_cb, (unsigned long)pdata);
crypto_init_queue(&pdata->queue, CRYPTO_QUEUE_LEN);
for (i = 0; i < ARRAY_SIZE(algs); i++) {
err = crypto_register_alg(&algs[i]);
if (err)
goto err_algs;
}
pr_info("s5p-sss driver registered\n");
return 0;
err_algs:
dev_err(dev, "can't register '%s': %d\n", algs[i].cra_name, err);
for (j = 0; j < i; j++)
crypto_unregister_alg(&algs[j]);
tasklet_kill(&pdata->tasklet);
err_irq:
clk_disable(pdata->clk);
s5p_dev = NULL;
platform_set_drvdata(pdev, NULL);
return err;
}
static int s5p_aes_remove(struct platform_device *pdev)
{
struct s5p_aes_dev *pdata = platform_get_drvdata(pdev);
int i;
if (!pdata)
return -ENODEV;
for (i = 0; i < ARRAY_SIZE(algs); i++)
crypto_unregister_alg(&algs[i]);
tasklet_kill(&pdata->tasklet);
clk_disable(pdata->clk);
s5p_dev = NULL;
platform_set_drvdata(pdev, NULL);
return 0;
}
static struct platform_driver s5p_aes_crypto = {
.probe = s5p_aes_probe,
.remove = s5p_aes_remove,
.driver = {
.owner = THIS_MODULE,
.name = "s5p-secss",
},
};
module_platform_driver(s5p_aes_crypto);
MODULE_DESCRIPTION("S5PV210 AES hw acceleration support.");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Vladimir Zapolskiy <vzapolskiy@gmail.com>");
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