[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: Alex Aizman <itn780@yahoo.com>
Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 5e8b313..0acc4b2 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -87,35 +87,32 @@
{
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 @@
* @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;
+ int offset = buf->sg.offset + buf->sent;
- 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);
- }
-
- 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 @@
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 @@
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 @@
* 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 @@
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 @@
}
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,
