Add support for Data Digest

This commit is contained in:
Brian Meagher
2024-05-04 18:54:21 -07:00
parent ec5d33da63
commit 882bcad53a
11 changed files with 254 additions and 17 deletions

View File

@@ -62,6 +62,7 @@
#include <sys/uio.h>
#endif
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
@@ -514,7 +515,7 @@ iscsi_out_queue_length(struct iscsi_context *iscsi)
}
ssize_t
iscsi_iovector_readv_writev(struct iscsi_context *iscsi, struct scsi_iovector *iovector, uint32_t pos, ssize_t count, int do_write)
iscsi_iovector_readv_writev(struct iscsi_context *iscsi, struct scsi_iovector *iovector, uint32_t pos, ssize_t count, uint32_t *data_digest_ptr, int do_write)
{
struct scsi_iovec *iov, *iov2;
int niov;
@@ -598,6 +599,19 @@ iscsi_iovector_readv_writev(struct iscsi_context *iscsi, struct scsi_iovector *i
n = readv(iscsi->fd, (struct iovec*) iov, niov);
}
/* Update the data digest */
if (data_digest_ptr && n > 0) {
int i;
size_t bytes_to_crc = n;
struct iovec *iov_ptr = (struct iovec*)iov;
for ( i=0; iov_ptr && i<niov && bytes_to_crc; iov_ptr++, i++) {
size_t chunk = MIN(bytes_to_crc, iov_ptr->iov_len);
*data_digest_ptr = crc32c_chain(*data_digest_ptr, iov_ptr->iov_base, chunk);
bytes_to_crc -= chunk;
}
}
/* restore original values */
iov->iov_base = (void*) ((uintptr_t)iov->iov_base - pos);
iov->iov_len += pos;
@@ -619,6 +633,7 @@ iscsi_read_from_socket(struct iscsi_context *iscsi)
{
struct iscsi_in_pdu *in;
ssize_t hdr_size, data_size, count, padding_size;
bool do_data_digest = (iscsi->data_digest != ISCSI_DATA_DIGEST_NONE);
do {
hdr_size = ISCSI_HEADER_SIZE(iscsi->header_digest);
@@ -628,6 +643,7 @@ iscsi_read_from_socket(struct iscsi_context *iscsi)
iscsi_set_error(iscsi, "Out-of-memory: failed to malloc iscsi_in_pdu");
return -1;
}
crc32c_init(&(iscsi->incoming->calculated_data_digest));
iscsi->incoming->hdr = iscsi_smalloc(iscsi, hdr_size);
if (iscsi->incoming->hdr == NULL) {
iscsi_set_error(iscsi, "Out-of-memory");
@@ -682,7 +698,7 @@ iscsi_read_from_socket(struct iscsi_context *iscsi)
iovector_in = iscsi_get_scsi_task_iovector_in(iscsi, in);
if (iovector_in != NULL && count > padding_size) {
uint32_t offset = scsi_get_uint32(&in->hdr[40]);
count = iscsi_iovector_readv_writev(iscsi, iovector_in, in->data_pos + offset, count - padding_size, 0);
count = iscsi_iovector_readv_writev(iscsi, iovector_in, in->data_pos + offset, count - padding_size, do_data_digest ? &(in->calculated_data_digest) : NULL, 0);
} else {
if (iovector_in == NULL) {
if (in->data == NULL) {
@@ -695,6 +711,8 @@ iscsi_read_from_socket(struct iscsi_context *iscsi)
buf = &in->data[in->data_pos];
}
count = recv(iscsi->fd, (void *)buf, count, 0);
if (do_data_digest && count > 0)
in->calculated_data_digest = crc32c_chain(in->calculated_data_digest, buf, count);
}
if (count == 0) {
/* remote side has closed the socket. */
@@ -713,6 +731,28 @@ iscsi_read_from_socket(struct iscsi_context *iscsi)
break;
}
/* Handle Data Digest receive */
if (data_size != 0 && do_data_digest &&
in->received_data_digest_bytes < ISCSI_DIGEST_SIZE) {
count = recv(iscsi->fd, (void *)(in->data_digest_buf + in->received_data_digest_bytes), ISCSI_DIGEST_SIZE - in->received_data_digest_bytes, 0);
if (count == 0) {
/* remote side has closed the socket. */
return -1;
}
if (count < 0) {
if (errno == EINTR || errno == EAGAIN) {
break;
}
return -1;
}
in->received_data_digest_bytes += count;
if (in->received_data_digest_bytes < ISCSI_DIGEST_SIZE) {
break;
}
}
iscsi->incoming = NULL;
if (iscsi_process_pdu(iscsi, in) != 0) {
iscsi_free_iscsi_in_pdu(iscsi, in);
@@ -751,6 +791,7 @@ iscsi_write_to_socket(struct iscsi_context *iscsi)
struct iscsi_pdu *pdu;
static char padding_buf[3];
int socket_flags = 0;
bool do_data_digest = (iscsi->data_digest != ISCSI_DATA_DIGEST_NONE);
#ifdef MSG_NOSIGNAL
socket_flags |= MSG_NOSIGNAL;
@@ -848,7 +889,7 @@ iscsi_write_to_socket(struct iscsi_context *iscsi)
count = iscsi_iovector_readv_writev(iscsi,
iovector_out,
pdu->payload_offset + pdu->payload_written,
pdu->payload_len - pdu->payload_written, 1);
pdu->payload_len - pdu->payload_written, do_data_digest ? &(pdu->calculated_data_digest) : NULL, 1);
if (count == -1) {
if (errno == EAGAIN || errno == EWOULDBLOCK) {
return 0;
@@ -873,12 +914,56 @@ iscsi_write_to_socket(struct iscsi_context *iscsi)
"socket :%d", errno);
return -1;
}
if (do_data_digest)
pdu->calculated_data_digest = crc32c_chain(pdu->calculated_data_digest, (uint8_t *)padding_buf, count);
pdu->payload_written += count;
}
/* if we havent written the full padding yet. */
if (pdu->payload_written < total) {
return 0;
}
/*
* Maybe update the total again, and write the digest, but only if
* 1. DataDigest has been negociated, and
* 2. We have actually written some data
*/
if (do_data_digest && pdu->payload_written) {
uint32_t data_digest = crc32c_chain_done(pdu->calculated_data_digest);
char data_digest_buf[ISCSI_DIGEST_SIZE];
total += ISCSI_DIGEST_SIZE;
data_digest_buf[3] = (data_digest >> 24);
data_digest_buf[2] = (data_digest >> 16);
data_digest_buf[1] = (data_digest >> 8);
data_digest_buf[0] = (data_digest);
/* Write data digest */
if (pdu->payload_written < total) {
int todo = total - pdu->payload_written;
count = send(iscsi->fd, data_digest_buf + (ISCSI_DIGEST_SIZE - todo), todo, socket_flags);
if (count == -1) {
if (errno == EAGAIN || errno == EWOULDBLOCK) {
return 0;
}
iscsi_set_error(iscsi, "Error when writing to "
"socket :%d", errno);
return -1;
}
pdu->payload_written += count;
}
}
/* if we havent written everything yet. */
if (pdu->payload_written != total) {
return 0;
}
if (pdu->flags & ISCSI_PDU_CORK_WHEN_SENT) {
iscsi->is_corked = 1;
}