evie/android_kernel_oneplus_msm8998
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i2c: virtio: reallocate memory for each msg buffer

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We'd better reallocate memory for each msg buffer to avoid
the memory in stack space be transferred to the backend for
the driver of i2c virtualization.

Change-Id: I6daa58cf819d4f612ae246b5a685898e28fbeb54
Signed-off-by: Xianbin Zhu <xianzhu@codeaurora.org>
This commit is contained in:
Xianbin Zhu 2019-06-17 20:51:03 +08:00
parent ca64572d54
commit 291c54b284
1 changed files with 20 additions and 13 deletions
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33
drivers/i2c/busses/virtio-i2c.c
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@ -130,20 +130,28 @@ static int virti2c_transfer_prepare(struct i2c_msg *msg_1,
i2c_req->head.length = msg_1->len; i2c_req->head.length = msg_1->len;
if (IS_ERR_OR_NULL(msg_2)) { if (IS_ERR_OR_NULL(msg_2)) {
i2c_req->head.type = (msg_1->flags & I2C_M_RD) ? i2c_req->buf = kzalloc(msg_1->len, GFP_KERNEL);
I2C_VIRTIO_RD : I2C_VIRTIO_WR; if (!i2c_req->buf)
i2c_req->buf = msg_1->buf; return -ENOMEM;
if (msg_1->flags & I2C_M_RD) {
i2c_req->head.type = I2C_VIRTIO_RD;
} else {
i2c_req->head.type = I2C_VIRTIO_WR;
memcpy(i2c_req->buf, msg_1->buf, msg_1->len);
}
} else { } else {
if (!msg_2->len || IS_ERR_OR_NULL(msg_2->buf)) if (!msg_2->len || IS_ERR_OR_NULL(msg_2->buf))
return -EINVAL; return -EINVAL;
i2c_req->buf = kzalloc((msg_1->len + msg_2->len), GFP_KERNEL);
if (!i2c_req->buf)
return -ENOMEM;
i2c_req->head.type = I2C_VIRTIO_RDWR; i2c_req->head.type = I2C_VIRTIO_RDWR;
i2c_req->head.total_length = msg_1->len + msg_2->len; i2c_req->head.total_length = msg_1->len + msg_2->len;
i2c_req->buf = kzalloc((msg_1->len + msg_2->len), GFP_KERNEL);
if (IS_ERR_OR_NULL(i2c_req->buf))
return -ENOMEM;
memcpy(i2c_req->buf, msg_1->buf, msg_1->len); memcpy(i2c_req->buf, msg_1->buf, msg_1->len);
} }
@ -153,13 +161,12 @@ static int virti2c_transfer_prepare(struct i2c_msg *msg_1,
static void virti2c_transfer_end(struct virtio_i2c_req *req, static void virti2c_transfer_end(struct virtio_i2c_req *req,
struct i2c_msg *msg) struct i2c_msg *msg)
{ {
if (req->head.type == I2C_VIRTIO_RDWR) { if (req->head.type == I2C_VIRTIO_RDWR)
memcpy(msg->buf, req->buf + req->head.length, msg->len); memcpy(msg->buf, req->buf + req->head.length, msg->len);
kfree(req->buf); else if (req->head.type == I2C_VIRTIO_RD)
req->buf = NULL; memcpy(msg->buf, req->buf, msg->len);
} kfree(req->buf);
req->buf = NULL;
memset(req, 0, sizeof(struct virtio_i2c_req));
} }
static int virtio_i2c_master_xfer(struct i2c_adapter *adap, static int virtio_i2c_master_xfer(struct i2c_adapter *adap,