in allwinner/sun4i-ss/sun4i-ss-cipher.c [179:400]
static int sun4i_ss_cipher_poll(struct skcipher_request *areq)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
struct sun4i_tfm_ctx *op = crypto_skcipher_ctx(tfm);
struct sun4i_ss_ctx *ss = op->ss;
int no_chunk = 1;
struct scatterlist *in_sg = areq->src;
struct scatterlist *out_sg = areq->dst;
unsigned int ivsize = crypto_skcipher_ivsize(tfm);
struct sun4i_cipher_req_ctx *ctx = skcipher_request_ctx(areq);
struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
struct sun4i_ss_alg_template *algt;
u32 mode = ctx->mode;
/* when activating SS, the default FIFO space is SS_RX_DEFAULT(32) */
u32 rx_cnt = SS_RX_DEFAULT;
u32 tx_cnt = 0;
u32 v;
u32 spaces;
int err = 0;
unsigned int i;
unsigned int ileft = areq->cryptlen;
unsigned int oleft = areq->cryptlen;
unsigned int todo;
void *backup_iv = NULL;
struct sg_mapping_iter mi, mo;
unsigned long pi = 0, po = 0; /* progress for in and out */
bool miter_err;
unsigned int oi, oo; /* offset for in and out */
unsigned int ob = 0; /* offset in buf */
unsigned int obo = 0; /* offset in bufo*/
unsigned int obl = 0; /* length of data in bufo */
unsigned long flags;
bool need_fallback = false;
if (!areq->cryptlen)
return 0;
if (!areq->src || !areq->dst) {
dev_err_ratelimited(ss->dev, "ERROR: Some SGs are NULL\n");
return -EINVAL;
}
algt = container_of(alg, struct sun4i_ss_alg_template, alg.crypto);
if (areq->cryptlen % algt->alg.crypto.base.cra_blocksize)
need_fallback = true;
/*
* if we have only SGs with size multiple of 4,
* we can use the SS optimized function
*/
while (in_sg && no_chunk == 1) {
if ((in_sg->length | in_sg->offset) & 3u)
no_chunk = 0;
in_sg = sg_next(in_sg);
}
while (out_sg && no_chunk == 1) {
if ((out_sg->length | out_sg->offset) & 3u)
no_chunk = 0;
out_sg = sg_next(out_sg);
}
if (no_chunk == 1 && !need_fallback)
return sun4i_ss_opti_poll(areq);
if (need_fallback)
return sun4i_ss_cipher_poll_fallback(areq);
if (areq->iv && ivsize > 0 && mode & SS_DECRYPTION) {
backup_iv = kzalloc(ivsize, GFP_KERNEL);
if (!backup_iv)
return -ENOMEM;
scatterwalk_map_and_copy(backup_iv, areq->src, areq->cryptlen - ivsize, ivsize, 0);
}
if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN4I_SS_DEBUG)) {
algt->stat_req++;
algt->stat_bytes += areq->cryptlen;
}
spin_lock_irqsave(&ss->slock, flags);
for (i = 0; i < op->keylen / 4; i++)
writesl(ss->base + SS_KEY0 + i * 4, &op->key[i], 1);
if (areq->iv) {
for (i = 0; i < 4 && i < ivsize / 4; i++) {
v = *(u32 *)(areq->iv + i * 4);
writesl(ss->base + SS_IV0 + i * 4, &v, 1);
}
}
writel(mode, ss->base + SS_CTL);
ileft = areq->cryptlen;
oleft = areq->cryptlen;
oi = 0;
oo = 0;
while (oleft) {
if (ileft) {
sg_miter_start(&mi, areq->src, sg_nents(areq->src),
SG_MITER_FROM_SG | SG_MITER_ATOMIC);
if (pi)
sg_miter_skip(&mi, pi);
miter_err = sg_miter_next(&mi);
if (!miter_err || !mi.addr) {
dev_err_ratelimited(ss->dev, "ERROR: sg_miter return null\n");
err = -EINVAL;
goto release_ss;
}
/*
* todo is the number of consecutive 4byte word that we
* can read from current SG
*/
todo = min(rx_cnt, ileft / 4);
todo = min_t(size_t, todo, (mi.length - oi) / 4);
if (todo && !ob) {
writesl(ss->base + SS_RXFIFO, mi.addr + oi,
todo);
ileft -= todo * 4;
oi += todo * 4;
} else {
/*
* not enough consecutive bytes, so we need to
* linearize in buf. todo is in bytes
* After that copy, if we have a multiple of 4
* we need to be able to write all buf in one
* pass, so it is why we min() with rx_cnt
*/
todo = min(rx_cnt * 4 - ob, ileft);
todo = min_t(size_t, todo, mi.length - oi);
memcpy(ss->buf + ob, mi.addr + oi, todo);
ileft -= todo;
oi += todo;
ob += todo;
if (!(ob % 4)) {
writesl(ss->base + SS_RXFIFO, ss->buf,
ob / 4);
ob = 0;
}
}
if (oi == mi.length) {
pi += mi.length;
oi = 0;
}
sg_miter_stop(&mi);
}
spaces = readl(ss->base + SS_FCSR);
rx_cnt = SS_RXFIFO_SPACES(spaces);
tx_cnt = SS_TXFIFO_SPACES(spaces);
if (!tx_cnt)
continue;
sg_miter_start(&mo, areq->dst, sg_nents(areq->dst),
SG_MITER_TO_SG | SG_MITER_ATOMIC);
if (po)
sg_miter_skip(&mo, po);
miter_err = sg_miter_next(&mo);
if (!miter_err || !mo.addr) {
dev_err_ratelimited(ss->dev, "ERROR: sg_miter return null\n");
err = -EINVAL;
goto release_ss;
}
/* todo in 4bytes word */
todo = min(tx_cnt, oleft / 4);
todo = min_t(size_t, todo, (mo.length - oo) / 4);
if (todo) {
readsl(ss->base + SS_TXFIFO, mo.addr + oo, todo);
oleft -= todo * 4;
oo += todo * 4;
if (oo == mo.length) {
po += mo.length;
oo = 0;
}
} else {
/*
* read obl bytes in bufo, we read at maximum for
* emptying the device
*/
readsl(ss->base + SS_TXFIFO, ss->bufo, tx_cnt);
obl = tx_cnt * 4;
obo = 0;
do {
/*
* how many bytes we can copy ?
* no more than remaining SG size
* no more than remaining buffer
* no need to test against oleft
*/
todo = min_t(size_t,
mo.length - oo, obl - obo);
memcpy(mo.addr + oo, ss->bufo + obo, todo);
oleft -= todo;
obo += todo;
oo += todo;
if (oo == mo.length) {
po += mo.length;
sg_miter_next(&mo);
oo = 0;
}
} while (obo < obl);
/* bufo must be fully used here */
}
sg_miter_stop(&mo);
}
if (areq->iv) {
if (mode & SS_DECRYPTION) {
memcpy(areq->iv, backup_iv, ivsize);
kfree_sensitive(backup_iv);
} else {
scatterwalk_map_and_copy(areq->iv, areq->dst, areq->cryptlen - ivsize,
ivsize, 0);
}
}
release_ss:
writel(0, ss->base + SS_CTL);
spin_unlock_irqrestore(&ss->slock, flags);
return err;
}