[PATCH 5.15 159/201] crypto: qat - use pre-allocated buffers in datapath
From: Greg Kroah-Hartman
Date: Wed Jul 27 2022 - 13:21:07 EST
From: Giovanni Cabiddu <giovanni.cabiddu@xxxxxxxxx>
[ Upstream commit e0831e7af4e03f2715de102e18e9179ec0a81562 ]
In order to do DMAs, the QAT device requires that the scatterlist
structures are mapped and translated into a format that the firmware can
understand. This is defined as the composition of a scatter gather list
(SGL) descriptor header, the struct qat_alg_buf_list, plus a variable
number of flat buffer descriptors, the struct qat_alg_buf.
The allocation and mapping of these data structures is done each time a
request is received from the skcipher and aead APIs.
In an OOM situation, this behaviour might lead to a dead-lock if an
allocation fails.
Based on the conversation in [1], increase the size of the aead and
skcipher request contexts to include an SGL descriptor that can handle
a maximum of 4 flat buffers.
If requests exceed 4 entries buffers, memory is allocated dynamically.
[1] https://lore.kernel.org/linux-crypto/20200722072932.GA27544@xxxxxxxxxxxxxxxxxxx/
Cc: stable@xxxxxxxxxxxxxxx
Fixes: d370cec32194 ("crypto: qat - Intel(R) QAT crypto interface")
Reported-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@xxxxxxxxx>
Reviewed-by: Marco Chiappero <marco.chiappero@xxxxxxxxx>
Reviewed-by: Wojciech Ziemba <wojciech.ziemba@xxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/crypto/qat/qat_common/qat_algs.c | 64 +++++++++++++---------
drivers/crypto/qat/qat_common/qat_crypto.h | 24 ++++++++
2 files changed, 61 insertions(+), 27 deletions(-)
diff --git a/drivers/crypto/qat/qat_common/qat_algs.c b/drivers/crypto/qat/qat_common/qat_algs.c
index f998ed58457c..ec635fe44c1f 100644
--- a/drivers/crypto/qat/qat_common/qat_algs.c
+++ b/drivers/crypto/qat/qat_common/qat_algs.c
@@ -46,19 +46,6 @@
static DEFINE_MUTEX(algs_lock);
static unsigned int active_devs;
-struct qat_alg_buf {
- u32 len;
- u32 resrvd;
- u64 addr;
-} __packed;
-
-struct qat_alg_buf_list {
- u64 resrvd;
- u32 num_bufs;
- u32 num_mapped_bufs;
- struct qat_alg_buf bufers[];
-} __packed __aligned(64);
-
/* Common content descriptor */
struct qat_alg_cd {
union {
@@ -693,7 +680,10 @@ static void qat_alg_free_bufl(struct qat_crypto_instance *inst,
bl->bufers[i].len, DMA_BIDIRECTIONAL);
dma_unmap_single(dev, blp, sz, DMA_TO_DEVICE);
- kfree(bl);
+
+ if (!qat_req->buf.sgl_src_valid)
+ kfree(bl);
+
if (blp != blpout) {
/* If out of place operation dma unmap only data */
int bufless = blout->num_bufs - blout->num_mapped_bufs;
@@ -704,7 +694,9 @@ static void qat_alg_free_bufl(struct qat_crypto_instance *inst,
DMA_BIDIRECTIONAL);
}
dma_unmap_single(dev, blpout, sz_out, DMA_TO_DEVICE);
- kfree(blout);
+
+ if (!qat_req->buf.sgl_dst_valid)
+ kfree(blout);
}
}
@@ -721,15 +713,24 @@ static int qat_alg_sgl_to_bufl(struct qat_crypto_instance *inst,
dma_addr_t blp = DMA_MAPPING_ERROR;
dma_addr_t bloutp = DMA_MAPPING_ERROR;
struct scatterlist *sg;
- size_t sz_out, sz = struct_size(bufl, bufers, n + 1);
+ size_t sz_out, sz = struct_size(bufl, bufers, n);
+ int node = dev_to_node(&GET_DEV(inst->accel_dev));
if (unlikely(!n))
return -EINVAL;
- bufl = kzalloc_node(sz, GFP_ATOMIC,
- dev_to_node(&GET_DEV(inst->accel_dev)));
- if (unlikely(!bufl))
- return -ENOMEM;
+ qat_req->buf.sgl_src_valid = false;
+ qat_req->buf.sgl_dst_valid = false;
+
+ if (n > QAT_MAX_BUFF_DESC) {
+ bufl = kzalloc_node(sz, GFP_ATOMIC, node);
+ if (unlikely(!bufl))
+ return -ENOMEM;
+ } else {
+ bufl = &qat_req->buf.sgl_src.sgl_hdr;
+ memset(bufl, 0, sizeof(struct qat_alg_buf_list));
+ qat_req->buf.sgl_src_valid = true;
+ }
for_each_sg(sgl, sg, n, i)
bufl->bufers[i].addr = DMA_MAPPING_ERROR;
@@ -760,12 +761,18 @@ static int qat_alg_sgl_to_bufl(struct qat_crypto_instance *inst,
struct qat_alg_buf *bufers;
n = sg_nents(sglout);
- sz_out = struct_size(buflout, bufers, n + 1);
+ sz_out = struct_size(buflout, bufers, n);
sg_nctr = 0;
- buflout = kzalloc_node(sz_out, GFP_ATOMIC,
- dev_to_node(&GET_DEV(inst->accel_dev)));
- if (unlikely(!buflout))
- goto err_in;
+
+ if (n > QAT_MAX_BUFF_DESC) {
+ buflout = kzalloc_node(sz_out, GFP_ATOMIC, node);
+ if (unlikely(!buflout))
+ goto err_in;
+ } else {
+ buflout = &qat_req->buf.sgl_dst.sgl_hdr;
+ memset(buflout, 0, sizeof(struct qat_alg_buf_list));
+ qat_req->buf.sgl_dst_valid = true;
+ }
bufers = buflout->bufers;
for_each_sg(sglout, sg, n, i)
@@ -810,7 +817,9 @@ static int qat_alg_sgl_to_bufl(struct qat_crypto_instance *inst,
dma_unmap_single(dev, buflout->bufers[i].addr,
buflout->bufers[i].len,
DMA_BIDIRECTIONAL);
- kfree(buflout);
+
+ if (!qat_req->buf.sgl_dst_valid)
+ kfree(buflout);
err_in:
if (!dma_mapping_error(dev, blp))
@@ -823,7 +832,8 @@ static int qat_alg_sgl_to_bufl(struct qat_crypto_instance *inst,
bufl->bufers[i].len,
DMA_BIDIRECTIONAL);
- kfree(bufl);
+ if (!qat_req->buf.sgl_src_valid)
+ kfree(bufl);
dev_err(dev, "Failed to map buf for dma\n");
return -ENOMEM;
diff --git a/drivers/crypto/qat/qat_common/qat_crypto.h b/drivers/crypto/qat/qat_common/qat_crypto.h
index b6a4c95ae003..0928f159ea99 100644
--- a/drivers/crypto/qat/qat_common/qat_crypto.h
+++ b/drivers/crypto/qat/qat_common/qat_crypto.h
@@ -21,6 +21,26 @@ struct qat_crypto_instance {
atomic_t refctr;
};
+#define QAT_MAX_BUFF_DESC 4
+
+struct qat_alg_buf {
+ u32 len;
+ u32 resrvd;
+ u64 addr;
+} __packed;
+
+struct qat_alg_buf_list {
+ u64 resrvd;
+ u32 num_bufs;
+ u32 num_mapped_bufs;
+ struct qat_alg_buf bufers[];
+} __packed;
+
+struct qat_alg_fixed_buf_list {
+ struct qat_alg_buf_list sgl_hdr;
+ struct qat_alg_buf descriptors[QAT_MAX_BUFF_DESC];
+} __packed __aligned(64);
+
struct qat_crypto_request_buffs {
struct qat_alg_buf_list *bl;
dma_addr_t blp;
@@ -28,6 +48,10 @@ struct qat_crypto_request_buffs {
dma_addr_t bloutp;
size_t sz;
size_t sz_out;
+ bool sgl_src_valid;
+ bool sgl_dst_valid;
+ struct qat_alg_fixed_buf_list sgl_src;
+ struct qat_alg_fixed_buf_list sgl_dst;
};
struct qat_crypto_request;
--
2.35.1