Commit 7cae5159 authored by Mike Christie's avatar Mike Christie Committed by James Bottomley

[SCSI] iscsi: add high mem support

From Mike Christie <michaelc@cs.wisc.edu> and FUJITA Tomonori <tomof@acm.org>:

We cannot use page_address becuase some pages could be highmem.
Instead, we can use sock_no_sendpage which does kmap for us.
Signed-off-by: default avatarAlex Aizman <itn780@yahoo.com>
Signed-off-by: default avatarDmitry Yusupov <dmitry_yus@yahoo.com>
Signed-off-by: default avatarMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 56851698
......@@ -87,35 +87,32 @@ iscsi_buf_init_virt(struct iscsi_buf *ibuf, char *vbuf, int size)
{
sg_init_one(&ibuf->sg, (u8 *)vbuf, size);
ibuf->sent = 0;
ibuf->use_sendmsg = 0;
}
static inline void
iscsi_buf_init_iov(struct iscsi_buf *ibuf, char *vbuf, int size)
{
ibuf->sg.page = (void*)vbuf;
ibuf->sg.offset = (unsigned int)-1;
ibuf->sg.page = virt_to_page(vbuf);
ibuf->sg.offset = offset_in_page(vbuf);
ibuf->sg.length = size;
ibuf->sent = 0;
}
static inline void*
iscsi_buf_iov_base(struct iscsi_buf *ibuf)
{
return (char*)ibuf->sg.page + ibuf->sent;
ibuf->use_sendmsg = 1;
}
static inline void
iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
{
ibuf->sg.page = sg->page;
ibuf->sg.offset = sg->offset;
ibuf->sg.length = sg->length;
/*
* Fastpath: sg element fits into single page
*/
if (sg->length + sg->offset <= PAGE_SIZE && page_count(sg->page) >= 2) {
ibuf->sg.page = sg->page;
ibuf->sg.offset = sg->offset;
ibuf->sg.length = sg->length;
} else
iscsi_buf_init_iov(ibuf, page_address(sg->page), sg->length);
if (sg->length + sg->offset <= PAGE_SIZE && page_count(sg->page) >= 2)
ibuf->use_sendmsg = 0;
else
ibuf->use_sendmsg = 1;
ibuf->sent = 0;
}
......@@ -1311,35 +1308,25 @@ iscsi_conn_restore_callbacks(struct iscsi_conn *conn)
* @buf: buffer to write from
* @size: actual size to write
* @flags: socket's flags
*
* Notes:
* depending on buffer will use tcp_sendpage() or tcp_sendmsg().
* buf->sg.offset == -1 tells us that buffer is non S/G and forces
* to use tcp_sendmsg().
*/
static inline int
iscsi_send(struct iscsi_conn *conn, struct iscsi_buf *buf, int size, int flags)
{
struct socket *sk = conn->sock;
int res;
if ((int)buf->sg.offset >= 0) {
int offset = buf->sg.offset + buf->sent;
res = conn->sendpage(sk, buf->sg.page, offset, size, flags);
} else {
struct msghdr msg;
buf->iov.iov_base = iscsi_buf_iov_base(buf);
buf->iov.iov_len = size;
memset(&msg, 0, sizeof(struct msghdr));
/* tcp_sendmsg */
res = kernel_sendmsg(sk, &msg, &buf->iov, 1, size);
}
int offset = buf->sg.offset + buf->sent;
return res;
/*
* if we got use_sg=0 or are sending something we kmallocd
* then we did not have to do kmap (kmap returns page_address)
*
* if we got use_sg > 0, but had to drop down, we do not
* set clustering so this should only happen for that
* slab case.
*/
if (buf->use_sendmsg)
return sock_no_sendpage(sk, buf->sg.page, offset, size, flags);
else
return conn->sendpage(sk, buf->sg.page, offset, size, flags);
}
/**
......@@ -1431,19 +1418,6 @@ iscsi_data_digest_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
ctask->digest_count = 4;
}
static inline void
iscsi_buf_data_digest_update(struct iscsi_conn *conn, struct iscsi_buf *buf)
{
struct scatterlist sg;
if (buf->sg.offset != -1)
crypto_digest_update(conn->data_tx_tfm, &buf->sg, 1);
else {
sg_init_one(&sg, (char *)buf->sg.page, buf->sg.length);
crypto_digest_update(conn->data_tx_tfm, &sg, 1);
}
}
static inline int
iscsi_digest_final_send(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_buf *buf, uint32_t *digest, int final)
......@@ -1806,7 +1780,8 @@ handle_xmstate_imm_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
return -EAGAIN;
}
if (conn->datadgst_en)
iscsi_buf_data_digest_update(conn, &ctask->sendbuf);
crypto_digest_update(conn->data_tx_tfm,
&ctask->sendbuf.sg, 1);
if (!ctask->imm_count)
break;
......@@ -1891,7 +1866,8 @@ handle_xmstate_uns_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
* so pass it
*/
if (conn->datadgst_en && ctask->sent - start > 0)
iscsi_buf_data_digest_update(conn, &ctask->sendbuf);
crypto_digest_update(conn->data_tx_tfm,
&ctask->sendbuf.sg, 1);
if (!ctask->data_count)
break;
......@@ -1969,7 +1945,7 @@ solicit_again:
BUG_ON(r2t->data_count < 0);
if (conn->datadgst_en)
iscsi_buf_data_digest_update(conn, &r2t->sendbuf);
crypto_digest_update(conn->data_tx_tfm, &r2t->sendbuf.sg, 1);
if (r2t->data_count) {
BUG_ON(ctask->sc->use_sg == 0);
......@@ -2051,7 +2027,7 @@ handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
}
if (conn->datadgst_en) {
iscsi_buf_data_digest_update(conn, &ctask->sendbuf);
crypto_digest_update(conn->data_tx_tfm, &ctask->sendbuf.sg, 1);
/* imm data? */
if (!dtask) {
if (iscsi_digest_final_send(conn, ctask, &ctask->immbuf,
......
......@@ -242,8 +242,8 @@ struct iscsi_session {
struct iscsi_buf {
struct scatterlist sg;
struct kvec iov;
unsigned int sent;
char use_sendmsg;
};
struct iscsi_data_task {
......
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