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authorOlaf Kirch <olaf.kirch@oracle.com>2007-12-13 21:43:35 +0300
committerJames Bottomley <James.Bottomley@HansenPartnership.com>2008-01-12 03:28:42 +0300
commita8ac6311cc21d78fa284cd43f56df2063f536bf1 (patch)
treec408dcccab2854dd9dd1775b5971ea60b34127dd /drivers/scsi/iscsi_tcp.c
parent1040c99d9fd9de2bf00efae6d91014f890575bdb (diff)
downloadlinux-a8ac6311cc21d78fa284cd43f56df2063f536bf1.tar.xz
[SCSI] iscsi: convert xmit path to iscsi chunks
Convert xmit to iscsi chunks. from michaelc@cs.wisc.edu: Bug fixes, more digest integration, sg chaining conversion and other sg wrapper changes, coding style sync up, and removal of io fields, like pdu_sent, that are not needed. Signed-off-by: Olaf Kirch <olaf.kirch@oracle.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'drivers/scsi/iscsi_tcp.c')
-rw-r--r--drivers/scsi/iscsi_tcp.c1333
1 files changed, 526 insertions, 807 deletions
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 9b418522c9bf..7212fe95a66d 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -68,56 +68,10 @@ static unsigned int iscsi_max_lun = 512;
module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
static int iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
- struct iscsi_chunk *chunk);
-
-static inline void
-iscsi_buf_init_iov(struct iscsi_buf *ibuf, char *vbuf, int size)
-{
- ibuf->sg.page = virt_to_page(vbuf);
- ibuf->sg.offset = offset_in_page(vbuf);
- ibuf->sg.length = size;
- ibuf->sent = 0;
- 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 && !PageSlab(sg->page))
- ibuf->use_sendmsg = 0;
- else
- ibuf->use_sendmsg = 1;
- ibuf->sent = 0;
-}
-
-static inline int
-iscsi_buf_left(struct iscsi_buf *ibuf)
-{
- int rc;
-
- rc = ibuf->sg.length - ibuf->sent;
- BUG_ON(rc < 0);
- return rc;
-}
-
-static inline void
-iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf,
- u8* crc)
-{
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-
- crypto_hash_digest(&tcp_conn->tx_hash, &buf->sg, buf->sg.length, crc);
- buf->sg.length += ISCSI_DIGEST_SIZE;
-}
+ struct iscsi_segment *segment);
/*
- * Scatterlist handling: inside the iscsi_chunk, we
+ * Scatterlist handling: inside the iscsi_segment, we
* remember an index into the scatterlist, and set data/size
* to the current scatterlist entry. For highmem pages, we
* kmap as needed.
@@ -130,60 +84,72 @@ iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf,
*/
/**
- * iscsi_tcp_chunk_init_sg - init indicated scatterlist entry
- * @chunk: the buffer object
- * @idx: index into scatterlist
+ * iscsi_tcp_segment_init_sg - init indicated scatterlist entry
+ * @segment: the buffer object
+ * @sg: scatterlist
* @offset: byte offset into that sg entry
*
- * This function sets up the chunk so that subsequent
+ * This function sets up the segment so that subsequent
* data is copied to the indicated sg entry, at the given
* offset.
*/
static inline void
-iscsi_tcp_chunk_init_sg(struct iscsi_chunk *chunk,
- unsigned int idx, unsigned int offset)
+iscsi_tcp_segment_init_sg(struct iscsi_segment *segment,
+ struct scatterlist *sg, unsigned int offset)
{
- struct scatterlist *sg;
-
- BUG_ON(chunk->sg == NULL);
-
- sg = &chunk->sg[idx];
- chunk->sg_index = idx;
- chunk->sg_offset = offset;
- chunk->size = min(sg->length - offset, chunk->total_size);
- chunk->data = NULL;
+ segment->sg = sg;
+ segment->sg_offset = offset;
+ segment->size = min(sg->length - offset,
+ segment->total_size - segment->total_copied);
+ segment->data = NULL;
}
/**
- * iscsi_tcp_chunk_map - map the current S/G page
- * @chunk: iscsi chunk
+ * iscsi_tcp_segment_map - map the current S/G page
+ * @segment: iscsi_segment
+ * @recv: 1 if called from recv path
*
* We only need to possibly kmap data if scatter lists are being used,
* because the iscsi passthrough and internal IO paths will never use high
* mem pages.
*/
static inline void
-iscsi_tcp_chunk_map(struct iscsi_chunk *chunk)
+iscsi_tcp_segment_map(struct iscsi_segment *segment, int recv)
{
struct scatterlist *sg;
- if (chunk->data != NULL || !chunk->sg)
+ if (segment->data != NULL || !segment->sg)
return;
- sg = &chunk->sg[chunk->sg_index];
- BUG_ON(chunk->sg_mapped);
+ sg = segment->sg;
+ BUG_ON(segment->sg_mapped);
BUG_ON(sg->length == 0);
- chunk->sg_mapped = kmap_atomic(sg->page, KM_SOFTIRQ0);
- chunk->data = chunk->sg_mapped + sg->offset + chunk->sg_offset;
+
+ /*
+ * If the page count is greater than one it is ok to send
+ * to the network layer's zero copy send path. If not we
+ * have to go the slow sendmsg path. We always map for the
+ * recv path.
+ */
+ if (page_count(sg_page(sg)) >= 1 && !recv)
+ return;
+
+ debug_tcp("iscsi_tcp_segment_map %s %p\n", recv ? "recv" : "xmit",
+ segment);
+ segment->sg_mapped = kmap_atomic(sg_page(sg), KM_SOFTIRQ0);
+ segment->data = segment->sg_mapped + sg->offset + segment->sg_offset;
}
static inline void
-iscsi_tcp_chunk_unmap(struct iscsi_chunk *chunk)
+iscsi_tcp_segment_unmap(struct iscsi_segment *segment)
{
- if (chunk->sg_mapped) {
- kunmap_atomic(chunk->sg_mapped, KM_SOFTIRQ0);
- chunk->sg_mapped = NULL;
- chunk->data = NULL;
+ debug_tcp("iscsi_tcp_segment_unmap %p\n", segment);
+
+ if (segment->sg_mapped) {
+ debug_tcp("iscsi_tcp_segment_unmap valid\n");
+ kunmap_atomic(segment->sg_mapped, KM_SOFTIRQ0);
+ segment->sg_mapped = NULL;
+ segment->data = NULL;
}
}
@@ -191,23 +157,24 @@ iscsi_tcp_chunk_unmap(struct iscsi_chunk *chunk)
* Splice the digest buffer into the buffer
*/
static inline void
-iscsi_tcp_chunk_splice_digest(struct iscsi_chunk *chunk, void *digest)
+iscsi_tcp_segment_splice_digest(struct iscsi_segment *segment, void *digest)
{
- chunk->data = digest;
- chunk->digest_len = ISCSI_DIGEST_SIZE;
- chunk->total_size += ISCSI_DIGEST_SIZE;
- chunk->size = ISCSI_DIGEST_SIZE;
- chunk->copied = 0;
- chunk->sg = NULL;
- chunk->sg_index = 0;
- chunk->hash = NULL;
+ segment->data = digest;
+ segment->digest_len = ISCSI_DIGEST_SIZE;
+ segment->total_size += ISCSI_DIGEST_SIZE;
+ segment->size = ISCSI_DIGEST_SIZE;
+ segment->copied = 0;
+ segment->sg = NULL;
+ segment->hash = NULL;
}
/**
- * iscsi_tcp_chunk_done - check whether the chunk is complete
- * @chunk: iscsi chunk to check
+ * iscsi_tcp_segment_done - check whether the segment is complete
+ * @segment: iscsi segment to check
+ * @recv: set to one of this is called from the recv path
+ * @copied: number of bytes copied
*
- * Check if we're done receiving this chunk. If the receive
+ * Check if we're done receiving this segment. If the receive
* buffer is full but we expect more data, move on to the
* next entry in the scatterlist.
*
@@ -217,62 +184,145 @@ iscsi_tcp_chunk_splice_digest(struct iscsi_chunk *chunk, void *digest)
* This function must be re-entrant.
*/
static inline int
-iscsi_tcp_chunk_done(struct iscsi_chunk *chunk)
+iscsi_tcp_segment_done(struct iscsi_segment *segment, int recv, unsigned copied)
{
static unsigned char padbuf[ISCSI_PAD_LEN];
+ struct scatterlist sg;
unsigned int pad;
- if (chunk->copied < chunk->size) {
- iscsi_tcp_chunk_map(chunk);
+ debug_tcp("copied %u %u size %u %s\n", segment->copied, copied,
+ segment->size, recv ? "recv" : "xmit");
+ if (segment->hash && copied) {
+ /*
+ * If a segment is kmapd we must unmap it before sending
+ * to the crypto layer since that will try to kmap it again.
+ */
+ iscsi_tcp_segment_unmap(segment);
+
+ if (!segment->data) {
+ sg_init_table(&sg, 1);
+ sg_set_page(&sg, sg_page(segment->sg), copied,
+ segment->copied + segment->sg_offset +
+ segment->sg->offset);
+ } else
+ sg_init_one(&sg, segment->data + segment->copied,
+ copied);
+ crypto_hash_update(segment->hash, &sg, copied);
+ }
+
+ segment->copied += copied;
+ if (segment->copied < segment->size) {
+ iscsi_tcp_segment_map(segment, recv);
return 0;
}
- chunk->total_copied += chunk->copied;
- chunk->copied = 0;
- chunk->size = 0;
+ segment->total_copied += segment->copied;
+ segment->copied = 0;
+ segment->size = 0;
/* Unmap the current scatterlist page, if there is one. */
- iscsi_tcp_chunk_unmap(chunk);
+ iscsi_tcp_segment_unmap(segment);
/* Do we have more scatterlist entries? */
- if (chunk->total_copied < chunk->total_size) {
+ debug_tcp("total copied %u total size %u\n", segment->total_copied,
+ segment->total_size);
+ if (segment->total_copied < segment->total_size) {
/* Proceed to the next entry in the scatterlist. */
- iscsi_tcp_chunk_init_sg(chunk, chunk->sg_index + 1, 0);
- iscsi_tcp_chunk_map(chunk);
- BUG_ON(chunk->size == 0);
+ iscsi_tcp_segment_init_sg(segment, sg_next(segment->sg),
+ 0);
+ iscsi_tcp_segment_map(segment, recv);
+ BUG_ON(segment->size == 0);
return 0;
}
/* Do we need to handle padding? */
- pad = iscsi_padding(chunk->total_copied);
+ pad = iscsi_padding(segment->total_copied);
if (pad != 0) {
debug_tcp("consume %d pad bytes\n", pad);
- chunk->total_size += pad;
- chunk->size = pad;
- chunk->data = padbuf;
+ segment->total_size += pad;
+ segment->size = pad;
+ segment->data = padbuf;
return 0;
}
/*
- * Set us up for receiving the data digest. hdr digest
+ * Set us up for transferring the data digest. hdr digest
* is completely handled in hdr done function.
*/
- if (chunk->hash) {
- if (chunk->digest_len == 0) {
- crypto_hash_final(chunk->hash, chunk->digest);
- iscsi_tcp_chunk_splice_digest(chunk,
- chunk->recv_digest);
- return 0;
- }
+ if (segment->hash) {
+ crypto_hash_final(segment->hash, segment->digest);
+ iscsi_tcp_segment_splice_digest(segment,
+ recv ? segment->recv_digest : segment->digest);
+ return 0;
}
return 1;
}
/**
- * iscsi_tcp_chunk_recv - copy data to chunk
+ * iscsi_tcp_xmit_segment - transmit segment
* @tcp_conn: the iSCSI TCP connection
- * @chunk: the buffer to copy to
+ * @segment: the buffer to transmnit
+ *
+ * This function transmits as much of the buffer as
+ * the network layer will accept, and returns the number of
+ * bytes transmitted.
+ *
+ * If CRC hashing is enabled, the function will compute the
+ * hash as it goes. When the entire segment has been transmitted,
+ * it will retrieve the hash value and send it as well.
+ */
+static int
+iscsi_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
+ struct iscsi_segment *segment)
+{
+ struct socket *sk = tcp_conn->sock;
+ unsigned int copied = 0;
+ int r = 0;
+
+ while (!iscsi_tcp_segment_done(segment, 0, r)) {
+ struct scatterlist *sg;
+ unsigned int offset, copy;
+ int flags = 0;
+
+ r = 0;
+ offset = segment->copied;
+ copy = segment->size - offset;
+
+ if (segment->total_copied + segment->size < segment->total_size)
+ flags |= MSG_MORE;
+
+ /* Use sendpage if we can; else fall back to sendmsg */
+ if (!segment->data) {
+ sg = segment->sg;
+ offset += segment->sg_offset + sg->offset;
+ r = tcp_conn->sendpage(sk, sg_page(sg), offset, copy,
+ flags);
+ } else {
+ struct msghdr msg = { .msg_flags = flags };
+ struct kvec iov = {
+ .iov_base = segment->data + offset,
+ .iov_len = copy
+ };
+
+ r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
+ }
+
+ if (r < 0) {
+ iscsi_tcp_segment_unmap(segment);
+ if (copied || r == -EAGAIN)
+ break;
+ return r;
+ }
+ copied += r;
+ }
+ return copied;
+}
+
+/**
+ * iscsi_tcp_segment_recv - copy data to segment
+ * @tcp_conn: the iSCSI TCP connection
+ * @segment: the buffer to copy to
* @ptr: data pointer
* @len: amount of data available
*
@@ -287,29 +337,24 @@ iscsi_tcp_chunk_done(struct iscsi_chunk *chunk)
* just way we do for network layer checksums.
*/
static int
-iscsi_tcp_chunk_recv(struct iscsi_tcp_conn *tcp_conn,
- struct iscsi_chunk *chunk, const void *ptr,
- unsigned int len)
+iscsi_tcp_segment_recv(struct iscsi_tcp_conn *tcp_conn,
+ struct iscsi_segment *segment, const void *ptr,
+ unsigned int len)
{
- struct scatterlist sg;
- unsigned int copy, copied = 0;
-
- while (!iscsi_tcp_chunk_done(chunk)) {
- if (copied == len)
- goto out;
+ unsigned int copy = 0, copied = 0;
- copy = min(len - copied, chunk->size - chunk->copied);
- memcpy(chunk->data + chunk->copied, ptr + copied, copy);
-
- if (chunk->hash) {
- sg_init_one(&sg, ptr + copied, copy);
- crypto_hash_update(chunk->hash, &sg, copy);
+ while (!iscsi_tcp_segment_done(segment, 1, copy)) {
+ if (copied == len) {
+ debug_tcp("iscsi_tcp_segment_recv copied %d bytes\n",
+ len);
+ break;
}
- chunk->copied += copy;
+
+ copy = min(len - copied, segment->size - segment->copied);
+ debug_tcp("iscsi_tcp_segment_recv copying %d\n", copy);
+ memcpy(segment->data + segment->copied, ptr + copied, copy);
copied += copy;
}
-
-out:
return copied;
}
@@ -325,12 +370,13 @@ iscsi_tcp_dgst_header(struct hash_desc *hash, const void *hdr, size_t hdrlen,
static inline int
iscsi_tcp_dgst_verify(struct iscsi_tcp_conn *tcp_conn,
- struct iscsi_chunk *chunk)
+ struct iscsi_segment *segment)
{
- if (!chunk->digest_len)
+ if (!segment->digest_len)
return 1;
- if (memcmp(chunk->recv_digest, chunk->digest, chunk->digest_len)) {
+ if (memcmp(segment->recv_digest, segment->digest,
+ segment->digest_len)) {
debug_scsi("digest mismatch\n");
return 0;
}
@@ -339,55 +385,59 @@ iscsi_tcp_dgst_verify(struct iscsi_tcp_conn *tcp_conn,
}
/*
- * Helper function to set up chunk buffer
+ * Helper function to set up segment buffer
*/
static inline void
-__iscsi_chunk_init(struct iscsi_chunk *chunk, size_t size,
- iscsi_chunk_done_fn_t *done, struct hash_desc *hash)
+__iscsi_segment_init(struct iscsi_segment *segment, size_t size,
+ iscsi_segment_done_fn_t *done, struct hash_desc *hash)
{
- memset(chunk, 0, sizeof(*chunk));
- chunk->total_size = size;
- chunk->done = done;
+ memset(segment, 0, sizeof(*segment));
+ segment->total_size = size;
+ segment->done = done;
if (hash) {
- chunk->hash = hash;
+ segment->hash = hash;
crypto_hash_init(hash);
}
}
static inline void
-iscsi_chunk_init_linear(struct iscsi_chunk *chunk, void *data, size_t size,
- iscsi_chunk_done_fn_t *done, struct hash_desc *hash)
+iscsi_segment_init_linear(struct iscsi_segment *segment, void *data,
+ size_t size, iscsi_segment_done_fn_t *done,
+ struct hash_desc *hash)
{
- __iscsi_chunk_init(chunk, size, done, hash);
- chunk->data = data;
- chunk->size = size;
+ __iscsi_segment_init(segment, size, done, hash);
+ segment->data = data;
+ segment->size = size;
}
static inline int
-iscsi_chunk_seek_sg(struct iscsi_chunk *chunk,
- struct scatterlist *sg, unsigned int sg_count,
- unsigned int offset, size_t size,
- iscsi_chunk_done_fn_t *done, struct hash_desc *hash)
+iscsi_segment_seek_sg(struct iscsi_segment *segment,
+ struct scatterlist *sg_list, unsigned int sg_count,
+ unsigned int offset, size_t size,
+ iscsi_segment_done_fn_t *done, struct hash_desc *hash)
{
+ struct scatterlist *sg;
unsigned int i;
- __iscsi_chunk_init(chunk, size, done, hash);
- for (i = 0; i < sg_count; ++i) {
- if (offset < sg[i].length) {
- chunk->sg = sg;
- chunk->sg_count = sg_count;
- iscsi_tcp_chunk_init_sg(chunk, i, offset);
+ debug_scsi("iscsi_segment_seek_sg offset %u size %llu\n",
+ offset, size);
+ __iscsi_segment_init(segment, size, done, hash);
+ for_each_sg(sg_list, sg, sg_count, i) {
+ debug_scsi("sg %d, len %u offset %u\n", i, sg->length,
+ sg->offset);
+ if (offset < sg->length) {
+ iscsi_tcp_segment_init_sg(segment, sg, offset);
return 0;
}
- offset -= sg[i].length;
+ offset -= sg->length;
}
return ISCSI_ERR_DATA_OFFSET;
}
/**
- * iscsi_tcp_hdr_recv_prep - prep chunk for hdr reception
+ * iscsi_tcp_hdr_recv_prep - prep segment for hdr reception
* @tcp_conn: iscsi connection to prep for
*
* This function always passes NULL for the hash argument, because when this
@@ -399,7 +449,7 @@ iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn)
{
debug_tcp("iscsi_tcp_hdr_recv_prep(%p%s)\n", tcp_conn,
tcp_conn->iscsi_conn->hdrdgst_en ? ", digest enabled" : "");
- iscsi_chunk_init_linear(&tcp_conn->in.chunk,
+ iscsi_segment_init_linear(&tcp_conn->in.segment,
tcp_conn->in.hdr_buf, sizeof(struct iscsi_hdr),
iscsi_tcp_hdr_recv_done, NULL);
}
@@ -409,12 +459,12 @@ iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn)
*/
static int
iscsi_tcp_data_recv_done(struct iscsi_tcp_conn *tcp_conn,
- struct iscsi_chunk *chunk)
+ struct iscsi_segment *segment)
{
struct iscsi_conn *conn = tcp_conn->iscsi_conn;
int rc = 0;
- if (!iscsi_tcp_dgst_verify(tcp_conn, chunk))
+ if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
return ISCSI_ERR_DATA_DGST;
rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr,
@@ -435,7 +485,7 @@ iscsi_tcp_data_recv_prep(struct iscsi_tcp_conn *tcp_conn)
if (conn->datadgst_en)
rx_hash = &tcp_conn->rx_hash;
- iscsi_chunk_init_linear(&tcp_conn->in.chunk,
+ iscsi_segment_init_linear(&tcp_conn->in.segment,
conn->data, tcp_conn->in.datalen,
iscsi_tcp_data_recv_done, rx_hash);
}
@@ -448,7 +498,6 @@ iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_r2t_info *r2t;
- struct scsi_cmnd *sc;
/* flush ctask's r2t queues */
while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
@@ -457,12 +506,12 @@ iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
debug_scsi("iscsi_tcp_cleanup_ctask pending r2t dropped\n");
}
- sc = ctask->sc;
- if (unlikely(!sc))
- return;
-
- tcp_ctask->xmstate = XMSTATE_IDLE;
- tcp_ctask->r2t = NULL;
+ r2t = tcp_ctask->r2t;
+ if (r2t != NULL) {
+ __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
+ sizeof(void*));
+ tcp_ctask->r2t = NULL;
+ }
}
/**
@@ -481,11 +530,6 @@ iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
int datasn = be32_to_cpu(rhdr->datasn);
iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
- /*
- * setup Data-In byte counter (gets decremented..)
- */
- ctask->data_count = tcp_conn->in.datalen;
-
if (tcp_conn->in.datalen == 0)
return 0;
@@ -543,9 +587,6 @@ iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_r2t_info *r2t)
{
struct iscsi_data *hdr;
- struct scsi_cmnd *sc = ctask->sc;
- int i, sg_count = 0;
- struct scatterlist *sg;
hdr = &r2t->dtask.hdr;
memset(hdr, 0, sizeof(struct iscsi_data));
@@ -569,34 +610,6 @@ iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
conn->dataout_pdus_cnt++;
r2t->sent = 0;
-
- iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
- sizeof(struct iscsi_hdr));
-
- sg = scsi_sglist(sc);
- r2t->sg = NULL;
- for (i = 0; i < scsi_sg_count(sc); i++, sg += 1) {
- /* FIXME: prefetch ? */
- if (sg_count + sg->length > r2t->data_offset) {
- int page_offset;
-
- /* sg page found! */
-
- /* offset within this page */
- page_offset = r2t->data_offset - sg_count;
-
- /* fill in this buffer */
- iscsi_buf_init_sg(&r2t->sendbuf, sg);
- r2t->sendbuf.sg.offset += page_offset;
- r2t->sendbuf.sg.length -= page_offset;
-
- /* xmit logic will continue with next one */
- r2t->sg = sg + 1;
- break;
- }
- sg_count += sg->length;
- }
- BUG_ON(r2t->sg == NULL);
}
/**
@@ -670,7 +683,6 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
tcp_ctask->exp_datasn = r2tsn + 1;
__kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
- tcp_ctask->xmstate |= XMSTATE_SOL_HDR_INIT;
conn->r2t_pdus_cnt++;
iscsi_requeue_ctask(ctask);
@@ -684,13 +696,13 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
*/
static int
iscsi_tcp_process_data_in(struct iscsi_tcp_conn *tcp_conn,
- struct iscsi_chunk *chunk)
+ struct iscsi_segment *segment)
{
struct iscsi_conn *conn = tcp_conn->iscsi_conn;
struct iscsi_hdr *hdr = tcp_conn->in.hdr;
int rc;
- if (!iscsi_tcp_dgst_verify(tcp_conn, chunk))
+ if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
return ISCSI_ERR_DATA_DGST;
/* check for non-exceptional status */
@@ -762,7 +774,7 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
/*
* Setup copy of Data-In into the Scsi_Cmnd
* Scatterlist case:
- * We set up the iscsi_chunk to point to the next
+ * We set up the iscsi_segment to point to the next
* scatterlist entry to copy to. As we go along,
* we move on to the next scatterlist entry and
* update the digest per-entry.
@@ -774,13 +786,13 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
"datalen=%d)\n", tcp_conn,
tcp_ctask->data_offset,
tcp_conn->in.datalen);
- return iscsi_chunk_seek_sg(&tcp_conn->in.chunk,
- scsi_sglist(ctask->sc),
- scsi_sg_count(ctask->sc),
- tcp_ctask->data_offset,
- tcp_conn->in.datalen,
- iscsi_tcp_process_data_in,
- rx_hash);
+ return iscsi_segment_seek_sg(&tcp_conn->in.segment,
+ scsi_sglist(ctask->sc),
+ scsi_sg_count(ctask->sc),
+ tcp_ctask->data_offset,
+ tcp_conn->in.datalen,
+ iscsi_tcp_process_data_in,
+ rx_hash);
}
/* fall through */
case ISCSI_OP_SCSI_CMD_RSP:
@@ -846,17 +858,6 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
return rc;
}
-static inline void
-partial_sg_digest_update(struct hash_desc *desc, struct scatterlist *sg,
- int offset, int length)
-{
- struct scatterlist temp;
-
- sg_init_table(&temp, 1);
- sg_set_page(&temp, sg_page(sg), length, offset);
- crypto_hash_update(desc, &temp, length);
-}
-
/**
* iscsi_tcp_hdr_recv_done - process PDU header
*
@@ -866,7 +867,7 @@ partial_sg_digest_update(struct hash_desc *desc, struct scatterlist *sg,
*/
static int
iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
- struct iscsi_chunk *chunk)
+ struct iscsi_segment *segment)
{
struct iscsi_conn *conn = tcp_conn->iscsi_conn;
struct iscsi_hdr *hdr;
@@ -876,7 +877,7 @@ iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
* may need to go back to the caller for more.
*/
hdr = (struct iscsi_hdr *) tcp_conn->in.hdr_buf;
- if (chunk->copied == sizeof(struct iscsi_hdr) && hdr->hlength) {
+ if (segment->copied == sizeof(struct iscsi_hdr) && hdr->hlength) {
/* Bump the header length - the caller will
* just loop around and get the AHS for us, and
* call again. */
@@ -886,8 +887,8 @@ iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
if (sizeof(*hdr) + ahslen > sizeof(tcp_conn->in.hdr_buf))
return ISCSI_ERR_AHSLEN;
- chunk->total_size += ahslen;
- chunk->size += ahslen;
+ segment->total_size += ahslen;
+ segment->size += ahslen;
return 0;
}
@@ -895,16 +896,16 @@ iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
* header digests; if so, set up the recv_digest buffer
* and go back for more. */
if (conn->hdrdgst_en) {
- if (chunk->digest_len == 0) {
- iscsi_tcp_chunk_splice_digest(chunk,
- chunk->recv_digest);
+ if (segment->digest_len == 0) {
+ iscsi_tcp_segment_splice_digest(segment,
+ segment->recv_digest);
return 0;
}
iscsi_tcp_dgst_header(&tcp_conn->rx_hash, hdr,
- chunk->total_copied - ISCSI_DIGEST_SIZE,
- chunk->digest);
+ segment->total_copied - ISCSI_DIGEST_SIZE,
+ segment->digest);
- if (!iscsi_tcp_dgst_verify(tcp_conn, chunk))
+ if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
return ISCSI_ERR_HDR_DGST;
}
@@ -925,7 +926,7 @@ iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
{
struct iscsi_conn *conn = rd_desc->arg.data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- struct iscsi_chunk *chunk = &tcp_conn->in.chunk;
+ struct iscsi_segment *segment = &tcp_conn->in.segment;
struct skb_seq_state seq;
unsigned int consumed = 0;
int rc = 0;
@@ -943,27 +944,31 @@ iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
const u8 *ptr;
avail = skb_seq_read(consumed, &ptr, &seq);
- if (avail == 0)
+ if (avail == 0) {
+ debug_tcp("no more data avail. Consumed %d\n",
+ consumed);
break;
- BUG_ON(chunk->copied >= chunk->size);
+ }
+ BUG_ON(segment->copied >= segment->size);
debug_tcp("skb %p ptr=%p avail=%u\n", skb, ptr, avail);
- rc = iscsi_tcp_chunk_recv(tcp_conn, chunk, ptr, avail);
+ rc = iscsi_tcp_segment_recv(tcp_conn, segment, ptr, avail);
BUG_ON(rc == 0);
consumed += rc;
- if (chunk->total_copied >= chunk->total_size) {
- rc = chunk->done(tcp_conn, chunk);
+ if (segment->total_copied >= segment->total_size) {
+ debug_tcp("segment done\n");
+ rc = segment->done(tcp_conn, segment);
if (rc != 0) {
skb_abort_seq_read(&seq);
goto error;
}
/* The done() functions sets up the
- * next chunk. */
+ * next segment. */
}
}
-
+ skb_abort_seq_read(&seq);
conn->rxdata_octets += consumed;
return consumed;
@@ -996,7 +1001,7 @@ iscsi_tcp_data_ready(struct sock *sk, int flag)
/* If we had to (atomically) map a highmem page,
* unmap it now. */
- iscsi_tcp_chunk_unmap(&tcp_conn->in.chunk);
+ iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
}
static void
@@ -1076,121 +1081,173 @@ iscsi_conn_restore_callbacks(struct iscsi_tcp_conn *tcp_conn)
}
/**
- * iscsi_send - generic send routine
- * @sk: kernel's socket
- * @buf: buffer to write from
- * @size: actual size to write
- * @flags: socket's flags
- */
-static inline int
-iscsi_send(struct iscsi_conn *conn, struct iscsi_buf *buf, int size, int flags)
+ * iscsi_xmit - TCP transmit
+ **/
+static int
+iscsi_xmit(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- struct socket *sk = tcp_conn->sock;
- int offset = buf->sg.offset + buf->sent, res;
+ struct iscsi_segment *segment = &tcp_conn->out.segment;
+ unsigned int consumed = 0;
+ int rc = 0;
- /*
- * 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)
- res = sock_no_sendpage(sk, buf->sg.page, offset, size, flags);
- else
- res = tcp_conn->sendpage(sk, buf->sg.page, offset, size, flags);
-
- if (res >= 0) {
- conn->txdata_octets += res;
- buf->sent += res;
- return res;
+ while (1) {
+ rc = iscsi_tcp_xmit_segment(tcp_conn, segment);
+ if (rc < 0)
+ goto error;
+ if (rc == 0)
+ break;
+
+ consumed += rc;
+
+ if (segment->total_copied >= segment->total_size) {
+ if (segment->done != NULL) {
+ rc = segment->done(tcp_conn, segment);
+ if (rc < 0)
+ goto error;
+ }
+ }
}
- tcp_conn->sendpage_failures_cnt++;
- if (res == -EAGAIN)
- res = -ENOBUFS;
- else
- iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
- return res;
+ debug_tcp("xmit %d bytes\n", consumed);
+
+ conn->txdata_octets += consumed;
+ return consumed;
+
+error:
+ /* Transmit error. We could initiate error recovery
+ * here. */
+ debug_tcp("Error sending PDU, errno=%d\n", rc);
+ iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+ return rc;
}
/**
- * iscsi_sendhdr - send PDU Header via tcp_sendpage()
- * @conn: iscsi connection
- * @buf: buffer to write from
- * @datalen: lenght of data to be sent after the header
- *
- * Notes:
- * (Tx, Fast Path)
- **/
+ * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
+ */
static inline int
-iscsi_sendhdr(struct iscsi_conn *conn, struct iscsi_buf *buf, int datalen)
+iscsi_tcp_xmit_qlen(struct iscsi_conn *conn)
{
- int flags = 0; /* MSG_DONTWAIT; */
- int res, size;
-
- size = buf->sg.length - buf->sent;
- BUG_ON(buf->sent + size > buf->sg.length);
- if (buf->sent + size != buf->sg.length || datalen)
- flags |= MSG_MORE;
-
- res = iscsi_send(conn, buf, size, flags);
- debug_tcp("sendhdr %d bytes, sent %d res %d\n", size, buf->sent, res);
- if (res >= 0) {
- if (size != res)
- return -EAGAIN;
- return 0;
- }
+ struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+ struct iscsi_segment *segment = &tcp_conn->out.segment;
- return res;
+ return segment->total_copied - segment->total_size;
}
-/**
- * iscsi_sendpage - send one page of iSCSI Data-Out.
- * @conn: iscsi connection
- * @buf: buffer to write from
- * @count: remaining data
- * @sent: number of bytes sent
- *
- * Notes:
- * (Tx, Fast Path)
- **/
static inline int
-iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
- int *count, int *sent)
+iscsi_tcp_flush(struct iscsi_conn *conn)
{
- int flags = 0; /* MSG_DONTWAIT; */
- int res, size;
-
- size = buf->sg.length - buf->sent;
- BUG_ON(buf->sent + size > buf->sg.length);
- if (size > *count)
- size = *count;
- if (buf->sent + size != buf->sg.length || *count != size)
- flags |= MSG_MORE;
-
- res = iscsi_send(conn, buf, size, flags);
- debug_tcp("sendpage: %d bytes, sent %d left %d sent %d res %d\n",
- size, buf->sent, *count, *sent, res);
- if (res >= 0) {
- *count -= res;
- *sent += res;
- if (size != res)
+ int rc;
+
+ while (iscsi_tcp_xmit_qlen(conn)) {
+ rc = iscsi_xmit(conn);
+ if (rc == 0)
return -EAGAIN;
- return 0;
+ if (rc < 0)
+ return rc;
}
- return res;
+ return 0;
}
-static inline void
-iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
- struct iscsi_tcp_cmd_task *tcp_ctask)
+/*
+ * This is called when we're done sending the header.
+ * Simply copy the data_segment to the send segment, and return.
+ */
+static int
+iscsi_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
+ struct iscsi_segment *segment)
{
- crypto_hash_init(&tcp_conn->tx_hash);
- tcp_ctask->digest_count = 4;
+ tcp_conn->out.segment = tcp_conn->out.data_segment;
+ debug_tcp("Header done. Next segment size %u total_size %u\n",
+ tcp_conn->out.segment.size, tcp_conn->out.segment.total_size);
+ return 0;
+}
+
+static void
+iscsi_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, size_t hdrlen)
+{
+ struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+
+ debug_tcp("%s(%p%s)\n", __FUNCTION__, tcp_conn,
+ conn->hdrdgst_en? ", digest enabled" : "");
+
+ /* Clear the data segment - needs to be filled in by the
+ * caller using iscsi_tcp_send_data_prep() */
+ memset(&tcp_conn->out.data_segment, 0, sizeof(struct iscsi_segment));
+
+ /* If header digest is enabled, compute the CRC and
+ * place the digest into the same buffer. We make
+ * sure that both iscsi_tcp_ctask and mtask have
+ * sufficient room.
+ */
+ if (conn->hdrdgst_en) {
+ iscsi_tcp_dgst_header(&tcp_conn->tx_hash, hdr, hdrlen,
+ hdr + hdrlen);
+ hdrlen += ISCSI_DIGEST_SIZE;
+ }
+
+ /* Remember header pointer for later, when we need
+ * to decide whether there's a payload to go along
+ * with the header. */
+ tcp_conn->out.hdr = hdr;
+
+ iscsi_segment_init_linear(&tcp_conn->out.segment, hdr, hdrlen,
+ iscsi_tcp_send_hdr_done, NULL);
+}
+
+/*
+ * Prepare the send buffer for the payload data.
+ * Padding and checksumming will all be taken care
+ * of by the iscsi_segment routines.
+ */
+static int
+iscsi_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
+ unsigned int count, unsigned int offset,
+ unsigned int len)
+{
+ struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+ struct hash_desc *tx_hash = NULL;
+ unsigned int hdr_spec_len;
+
+ debug_tcp("%s(%p, offset=%d, datalen=%d%s)\n", __FUNCTION__,
+ tcp_conn, offset, len,
+ conn->datadgst_en? ", digest enabled" : "");
+
+ /* Make sure the datalen matches what the caller
+ said he would send. */
+ hdr_spec_len = ntoh24(tcp_conn->out.hdr->dlength);
+ WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
+
+ if (conn->datadgst_en)
+ tx_hash = &tcp_conn->tx_hash;
+
+ return iscsi_segment_seek_sg(&tcp_conn->out.data_segment,
+ sg, count, offset, len,
+ NULL, tx_hash);
+}
+
+static void
+iscsi_tcp_send_linear_data_prepare(struct iscsi_conn *conn, void *data,
+ size_t len)
+{
+ struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+ struct hash_desc *tx_hash = NULL;
+ unsigned int hdr_spec_len;
+
+ debug_tcp("%s(%p, datalen=%d%s)\n", __FUNCTION__, tcp_conn, len,
+ conn->datadgst_en? ", digest enabled" : "");
+
+ /* Make sure the datalen matches what the caller
+ said he would send. */
+ hdr_spec_len = ntoh24(tcp_conn->out.hdr->dlength);
+ WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
+
+ if (conn->datadgst_en)
+ tx_hash = &tcp_conn->tx_hash;
+
+ iscsi_segment_init_linear(&tcp_conn->out.data_segment,
+ data, len, NULL, tx_hash);
}
/**
@@ -1206,12 +1263,17 @@ iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
*
* Called under connection lock.
**/
-static void
+static int
iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
- struct iscsi_r2t_info *r2t, int left)
+ struct iscsi_r2t_info *r2t)
{
struct iscsi_data *hdr;
- int new_offset;
+ int new_offset, left;
+
+ BUG_ON(r2t->data_length - r2t->sent < 0);
+ left = r2t->data_length - r2t->sent;
+ if (left == 0)
+ return 0;
hdr = &r2t->dtask.hdr;
memset(hdr, 0, sizeof(struct iscsi_data));
@@ -1232,43 +1294,46 @@ iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
r2t->data_count = left;
hdr->flags = ISCSI_FLAG_CMD_FINAL;
}
- conn->dataout_pdus_cnt++;
-
- iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
- sizeof(struct iscsi_hdr));
-
- if (iscsi_buf_left(&r2t->sendbuf))
- return;
-
- iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
- r2t->sg += 1;
-}
-
-static void iscsi_set_padding(struct iscsi_tcp_cmd_task *tcp_ctask,
- unsigned long len)
-{
- tcp_ctask->pad_count = len & (ISCSI_PAD_LEN - 1);
- if (!tcp_ctask->pad_count)
- return;
- tcp_ctask->pad_count = ISCSI_PAD_LEN - tcp_ctask->pad_count;
- debug_scsi("write padding %d bytes\n", tcp_ctask->pad_count);
- tcp_ctask->xmstate |= XMSTATE_W_PAD;
+ conn->dataout_pdus_cnt++;
+ return 1;
}
/**
- * iscsi_tcp_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
+ * iscsi_tcp_ctask - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
* @conn: iscsi connection
* @ctask: scsi command task
* @sc: scsi command
**/
-static void
-iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
+static int
+iscsi_tcp_ctask_init(struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
+ struct iscsi_conn *conn = ctask->conn;
+ struct scsi_cmnd *sc = ctask->sc;
+ int err;
BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
- tcp_ctask->xmstate = XMSTATE_CMD_HDR_INIT;
+ tcp_ctask->sent = 0;
+ tcp_ctask->exp_datasn = 0;
+
+ /* Prepare PDU, optionally w/ immediate data */
+ debug_scsi("ctask deq [cid %d itt 0x%x imm %d unsol %d]\n",
+ conn->id, ctask->itt, ctask->imm_count,
+ ctask->unsol_count);
+ iscsi_tcp_send_hdr_prep(conn, ctask->hdr, ctask->hdr_len);
+
+ if (!ctask->imm_count)
+ return 0;
+
+ /* If we have immediate data, attach a payload */
+ err = iscsi_tcp_send_data_prep(conn, scsi_sglist(sc), scsi_sg_count(sc),
+ 0, ctask->imm_count);
+ if (err)
+ return err;
+ tcp_ctask->sent += ctask->imm_count;
+ ctask->imm_count = 0;
+ return 0;
}
/**
@@ -1280,71 +1345,17 @@ iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
* The function can return -EAGAIN in which case caller must
* call it again later, or recover. '0' return code means successful
* xmit.
- *
- * Management xmit state machine consists of these states:
- * XMSTATE_IMM_HDR_INIT - calculate digest of PDU Header
- * XMSTATE_IMM_HDR - PDU Header xmit in progress
- * XMSTATE_IMM_DATA - PDU Data xmit in progress
- * XMSTATE_IDLE - management PDU is done
**/
static int
iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
{
- struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
int rc;
- debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
- conn->id, tcp_mtask->xmstate, mtask->itt);
-
- if (tcp_mtask->xmstate & XMSTATE_IMM_HDR_INIT) {
- iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
- sizeof(struct iscsi_hdr));
-
- if (mtask->data_count) {
- tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
- iscsi_buf_init_iov(&tcp_mtask->sendbuf,
- (char*)mtask->data,
- mtask->data_count);
- }
-
- if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
- conn->stop_stage != STOP_CONN_RECOVER &&
- conn->hdrdgst_en)
- iscsi_hdr_digest(conn, &tcp_mtask->headbuf,
- (u8*)tcp_mtask->hdrext);
-
- tcp_mtask->sent = 0;
- tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR_INIT;
- tcp_mtask->xmstate |= XMSTATE_IMM_HDR;
- }
-
- if (tcp_mtask->xmstate & XMSTATE_IMM_HDR) {
- rc = iscsi_sendhdr(conn, &tcp_mtask->headbuf,
- mtask->data_count);
- if (rc)
- return rc;
- tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR;
- }
-
- if (tcp_mtask->xmstate & XMSTATE_IMM_DATA) {
- BUG_ON(!mtask->data_count);
- tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
- /* FIXME: implement.
- * Virtual buffer could be spreaded across multiple pages...
- */
- do {
- int rc;
-
- rc = iscsi_sendpage(conn, &tcp_mtask->sendbuf,
- &mtask->data_count, &tcp_mtask->sent);
- if (rc) {
- tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
- return rc;
- }
- } while (mtask->data_count);
- }
+ /* Flush any pending data first. */
+ rc = iscsi_tcp_flush(conn);
+ if (rc < 0)
+ return rc;
- BUG_ON(tcp_mtask->xmstate != XMSTATE_IDLE);
if (mtask->hdr->itt == RESERVED_ITT) {
struct iscsi_session *session = conn->session;
@@ -1352,411 +1363,112 @@ iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
iscsi_free_mgmt_task(conn, mtask);
spin_unlock_bh(&session->lock);
}
+
return 0;
}
+/*
+ * iscsi_tcp_ctask_xmit - xmit normal PDU task
+ * @conn: iscsi connection
+ * @ctask: iscsi command task
+ *
+ * We're expected to return 0 when everything was transmitted succesfully,
+ * -EAGAIN if there's still data in the queue, or != 0 for any other kind
+ * of error.
+ */
static int
-iscsi_send_cmd_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
- struct scsi_cmnd *sc = ctask->sc;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
+ struct scsi_cmnd *sc = ctask->sc;
int rc = 0;
- if (tcp_ctask->xmstate & XMSTATE_CMD_HDR_INIT) {
- tcp_ctask->sent = 0;
- tcp_ctask->sg_count = 0;
- tcp_ctask->exp_datasn = 0;
-
- if (sc->sc_data_direction == DMA_TO_DEVICE) {
- struct scatterlist *sg = scsi_sglist(sc);
-
- iscsi_buf_init_sg(&tcp_ctask->sendbuf, sg);
- tcp_ctask->sg = sg + 1;
- tcp_ctask->bad_sg = sg + scsi_sg_count(sc);
-
- debug_scsi("cmd [itt 0x%x total %d imm_data %d "
- "unsol count %d, unsol offset %d]\n",
- ctask->itt, scsi_bufflen(sc),
- ctask->imm_count, ctask->unsol_count,
- ctask->unsol_offset);
- }
-
- iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
- ctask->hdr_len);
-
- if (conn->hdrdgst_en)
- iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
- iscsi_next_hdr(ctask));
- tcp_ctask->xmstate &= ~XMSTATE_CMD_HDR_INIT;
- tcp_ctask->xmstate |= XMSTATE_CMD_HDR_XMIT;
- }
-
- if (tcp_ctask->xmstate & XMSTATE_CMD_HDR_XMIT) {
- rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
- if (rc)
- return rc;
- tcp_ctask->xmstate &= ~XMSTATE_CMD_HDR_XMIT;
-
- if (sc->sc_data_direction != DMA_TO_DEVICE)
- return 0;
-
- if (ctask->imm_count) {
- tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
- iscsi_set_padding(tcp_ctask, ctask->imm_count);
-
- if (ctask->conn->datadgst_en) {
- iscsi_data_digest_init(ctask->conn->dd_data,
- tcp_ctask);
- tcp_ctask->immdigest = 0;
- }
- }
-
- if (ctask->unsol_count)
- tcp_ctask->xmstate |=
- XMSTATE_UNS_HDR | XMSTATE_UNS_INIT;
- }
- return rc;
-}
-
-static int
-iscsi_send_padding(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- int sent = 0, rc;
-
- if (tcp_ctask->xmstate & XMSTATE_W_PAD) {
- iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
- tcp_ctask->pad_count);
- if (conn->datadgst_en)
- crypto_hash_update(&tcp_conn->tx_hash,
- &tcp_ctask->sendbuf.sg,
- tcp_ctask->sendbuf.sg.length);
- } else if (!(tcp_ctask->xmstate & XMSTATE_W_RESEND_PAD))
- return 0;
-
- tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
- tcp_ctask->xmstate &= ~XMSTATE_W_RESEND_PAD;
- debug_scsi("sending %d pad bytes for itt 0x%x\n",
- tcp_ctask->pad_count, ctask->itt);
- rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf, &tcp_ctask->pad_count,
- &sent);
- if (rc) {
- debug_scsi("padding send failed %d\n", rc);
- tcp_ctask->xmstate |= XMSTATE_W_RESEND_PAD;
- }
- return rc;
-}
-
-static int
-iscsi_send_digest(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
- struct iscsi_buf *buf, uint32_t *digest)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask;
- struct iscsi_tcp_conn *tcp_conn;
- int rc, sent = 0;
-
- if (!conn->datadgst_en)
- return 0;
-
- tcp_ctask = ctask->dd_data;
- tcp_conn = conn->dd_data;
-
- if (!(tcp_ctask->xmstate & XMSTATE_W_RESEND_DATA_DIGEST)) {
- crypto_hash_final(&tcp_conn->tx_hash, (u8*)digest);
- iscsi_buf_init_iov(buf, (char*)digest, 4);
- }
- tcp_ctask->xmstate &= ~XMSTATE_W_RESEND_DATA_DIGEST;
-
- rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
- if (!rc)
- debug_scsi("sent digest 0x%x for itt 0x%x\n", *digest,
- ctask->itt);
- else {
- debug_scsi("sending digest 0x%x failed for itt 0x%x!\n",
- *digest, ctask->itt);
- tcp_ctask->xmstate |= XMSTATE_W_RESEND_DATA_DIGEST;
- }
- return rc;
-}
-
-static int
-iscsi_send_data(struct iscsi_cmd_task *ctask, struct iscsi_buf *sendbuf,
- struct scatterlist **sg, int *sent, int *count,
- struct iscsi_buf *digestbuf, uint32_t *digest)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct iscsi_conn *conn = ctask->conn;
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- int rc, buf_sent, offset;
-
- while (*count) {
- buf_sent = 0;
- offset = sendbuf->sent;
-
- rc = iscsi_sendpage(conn, sendbuf, count, &buf_sent);
- *sent = *sent + buf_sent;
- if (buf_sent && conn->datadgst_en)
- partial_sg_digest_update(&tcp_conn->tx_hash,
- &sendbuf->sg, sendbuf->sg.offset + offset,
- buf_sent);
- if (!iscsi_buf_left(sendbuf) && *sg != tcp_ctask->bad_sg) {
- iscsi_buf_init_sg(sendbuf, *sg);
- *sg = *sg + 1;
- }
-
- if (rc)
- return rc;
- }
-
- rc = iscsi_send_padding(conn, ctask);
- if (rc)
+flush:
+ /* Flush any pending data first. */
+ rc = iscsi_tcp_flush(conn);
+ if (rc < 0)
return rc;
- return iscsi_send_digest(conn, ctask, digestbuf, digest);
-}
-
-static int
-iscsi_send_unsol_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct iscsi_data_task *dtask;
- int rc;
-
- tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
- if (tcp_ctask->xmstate & XMSTATE_UNS_INIT) {
- dtask = &tcp_ctask->unsol_dtask;
-
- iscsi_prep_unsolicit_data_pdu(ctask, &dtask->hdr);
- iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)&dtask->hdr,
- sizeof(struct iscsi_hdr));
- if (conn->hdrdgst_en)
- iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
- (u8*)dtask->hdrext);
-
- tcp_ctask->xmstate &= ~XMSTATE_UNS_INIT;
- iscsi_set_padding(tcp_ctask, ctask->data_count);
- }
-
- rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->data_count);
- if (rc) {
- tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
- tcp_ctask->xmstate |= XMSTATE_UNS_HDR;
- return rc;
- }
+ /* Are we done already? */
+ if (sc->sc_data_direction != DMA_TO_DEVICE)
+ return 0;
- if (conn->datadgst_en) {
- dtask = &tcp_ctask->unsol_dtask;
- iscsi_data_digest_init(ctask->conn->dd_data, tcp_ctask);
- dtask->digest = 0;
- }
+ if (ctask->unsol_count != 0) {
+ struct iscsi_data *hdr = &tcp_ctask->unsol_dtask.hdr;
- debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
- ctask->itt, ctask->unsol_count, tcp_ctask->sent);
- return 0;
-}
+ /* Prepare a header for the unsolicited PDU.
+ * The amount of data we want to send will be
+ * in ctask->data_count.
+ * FIXME: return the data count instead.
+ */
+ iscsi_prep_unsolicit_data_pdu(ctask, hdr);
-static int
-iscsi_send_unsol_pdu(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- int rc;
+ debug_tcp("unsol dout [itt 0x%x doff %d dlen %d]\n",
+ ctask->itt, tcp_ctask->sent, ctask->data_count);
- if (tcp_ctask->xmstate & XMSTATE_UNS_HDR) {
- BUG_ON(!ctask->unsol_count);
- tcp_ctask->xmstate &= ~XMSTATE_UNS_HDR;
-send_hdr:
- rc = iscsi_send_unsol_hdr(conn, ctask);
+ iscsi_tcp_send_hdr_prep(conn, hdr, sizeof(*hdr));
+ rc = iscsi_tcp_send_data_prep(conn, scsi_sglist(sc),
+ scsi_sg_count(sc),
+ tcp_ctask->sent,
+ ctask->data_count);
if (rc)
- return rc;
- }
-
- if (tcp_ctask->xmstate & XMSTATE_UNS_DATA) {
- struct iscsi_data_task *dtask = &tcp_ctask->unsol_dtask;
- int start = tcp_ctask->sent;
+ goto fail;
+ tcp_ctask->sent += ctask->data_count;
+ ctask->unsol_count -= ctask->data_count;
+ goto flush;
+ } else {
+ struct iscsi_session *session = conn->session;
+ struct iscsi_r2t_info *r2t;
- rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
- &tcp_ctask->sent, &ctask->data_count,
- &dtask->digestbuf, &dtask->digest);
- ctask->unsol_count -= tcp_ctask->sent - start;
- if (rc)
- return rc;
- tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
- /*
- * Done with the Data-Out. Next, check if we need
- * to send another unsolicited Data-Out.
+ /* All unsolicited PDUs sent. Check for solicited PDUs.
*/
- if (ctask->unsol_count) {
- debug_scsi("sending more uns\n");
- tcp_ctask->xmstate |= XMSTATE_UNS_INIT;
- goto send_hdr;
+ spin_lock_bh(&session->lock);
+ r2t = tcp_ctask->r2t;
+ if (r2t != NULL) {
+ /* Continue with this R2T? */
+ if (!iscsi_solicit_data_cont(conn, ctask, r2t)) {
+ debug_scsi(" done with r2t %p\n", r2t);
+
+ __kfifo_put(tcp_ctask->r2tpool.queue,
+ (void*)&r2t, sizeof(void*));
+ tcp_ctask->r2t = r2t = NULL;
+ }
}
- }
- return 0;
-}
-static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
- struct iscsi_cmd_task *ctask)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct iscsi_session *session = conn->session;
- struct iscsi_r2t_info *r2t;
- struct iscsi_data_task *dtask;
- int left, rc;
-
- if (tcp_ctask->xmstate & XMSTATE_SOL_HDR_INIT) {
- if (!tcp_ctask->r2t) {
- spin_lock_bh(&session->lock);
+ if (r2t == NULL) {
__kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
sizeof(void*));
- spin_unlock_bh(&session->lock);
+ r2t = tcp_ctask->r2t;
}
-send_hdr:
- r2t = tcp_ctask->r2t;
- dtask = &r2t->dtask;
-
- if (conn->hdrdgst_en)
- iscsi_hdr_digest(conn, &r2t->headbuf,
- (u8*)dtask->hdrext);
- tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR_INIT;
- tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
- }
-
- if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
- r2t = tcp_ctask->r2t;
- dtask = &r2t->dtask;
-
- rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
- if (rc)
- return rc;
- tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
- tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
+ spin_unlock_bh(&session->lock);
- if (conn->datadgst_en) {
- iscsi_data_digest_init(conn->dd_data, tcp_ctask);
- dtask->digest = 0;
+ /* Waiting for more R2Ts to arrive. */
+ if (r2t == NULL) {
+ debug_tcp("no R2Ts yet\n");
+ return 0;
}
- iscsi_set_padding(tcp_ctask, r2t->data_count);
- debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
- r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
- r2t->sent);
- }
+ debug_scsi("sol dout %p [dsn %d itt 0x%x doff %d dlen %d]\n",
+ r2t, r2t->solicit_datasn - 1, ctask->itt,
+ r2t->data_offset + r2t->sent, r2t->data_count);
- if (tcp_ctask->xmstate & XMSTATE_SOL_DATA) {
- r2t = tcp_ctask->r2t;
- dtask = &r2t->dtask;
+ iscsi_tcp_send_hdr_prep(conn, &r2t->dtask.hdr,
+ sizeof(struct iscsi_hdr));
- rc = iscsi_send_data(ctask, &r2t->sendbuf, &r2t->sg,
- &r2t->sent, &r2t->data_count,
- &dtask->digestbuf, &dtask->digest);
+ rc = iscsi_tcp_send_data_prep(conn, scsi_sglist(sc),
+ scsi_sg_count(sc),
+ r2t->data_offset + r2t->sent,
+ r2t->data_count);
if (rc)
- return rc;
- tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
-
- /*
- * Done with this Data-Out. Next, check if we have
- * to send another Data-Out for this R2T.
- */
- BUG_ON(r2t->data_length - r2t->sent < 0);
- left = r2t->data_length - r2t->sent;
- if (left) {
- iscsi_solicit_data_cont(conn, ctask, r2t, left);
- goto send_hdr;
- }
-
- /*
- * Done with this R2T. Check if there are more
- * outstanding R2Ts ready to be processed.
- */
- spin_lock_bh(&session->lock);
- tcp_ctask->r2t = NULL;
- __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
- sizeof(void*));
- if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t,
- sizeof(void*))) {
- tcp_ctask->r2t = r2t;
- spin_unlock_bh(&session->lock);
- goto send_hdr;
- }
- spin_unlock_bh(&session->lock);
+ goto fail;
+ tcp_ctask->sent += r2t->data_count;
+ r2t->sent += r2t->data_count;
+ goto flush;
}
return 0;
-}
-
-/**
- * iscsi_tcp_ctask_xmit - xmit normal PDU task
- * @conn: iscsi connection
- * @ctask: iscsi command task
- *
- * Notes:
- * The function can return -EAGAIN in which case caller must
- * call it again later, or recover. '0' return code means successful
- * xmit.
- * The function is devided to logical helpers (above) for the different
- * xmit stages.
- *
- *iscsi_send_cmd_hdr()
- * XMSTATE_CMD_HDR_INIT - prepare Header and Data buffers Calculate
- * Header Digest
- * XMSTATE_CMD_HDR_XMIT - Transmit header in progress
- *
- *iscsi_send_padding
- * XMSTATE_W_PAD - Prepare and send pading
- * XMSTATE_W_RESEND_PAD - retry send pading
- *
- *iscsi_send_digest
- * XMSTATE_W_RESEND_DATA_DIGEST - Finalize and send Data Digest
- * XMSTATE_W_RESEND_DATA_DIGEST - retry sending digest
- *
- *iscsi_send_unsol_hdr
- * XMSTATE_UNS_INIT - prepare un-solicit data header and digest
- * XMSTATE_UNS_HDR - send un-solicit header
- *
- *iscsi_send_unsol_pdu
- * XMSTATE_UNS_DATA - send un-solicit data in progress
- *
- *iscsi_send_sol_pdu
- * XMSTATE_SOL_HDR_INIT - solicit data header and digest initialize
- * XMSTATE_SOL_HDR - send solicit header
- * XMSTATE_SOL_DATA - send solicit data
- *
- *iscsi_tcp_ctask_xmit
- * XMSTATE_IMM_DATA - xmit managment data (??)
- **/
-static int
-iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- int rc = 0;
-
- debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
- conn->id, tcp_ctask->xmstate, ctask->itt);
-
- rc = iscsi_send_cmd_hdr(conn, ctask);
- if (rc)
- return rc;
- if (ctask->sc->sc_data_direction != DMA_TO_DEVICE)
- return 0;
-
- if (tcp_ctask->xmstate & XMSTATE_IMM_DATA) {
- rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
- &tcp_ctask->sent, &ctask->imm_count,
- &tcp_ctask->immbuf, &tcp_ctask->immdigest);
- if (rc)
- return rc;
- tcp_ctask->xmstate &= ~XMSTATE_IMM_DATA;
- }
-
- rc = iscsi_send_unsol_pdu(conn, ctask);
- if (rc)
- return rc;
-
- rc = iscsi_send_sol_pdu(conn, ctask);
- if (rc)
- return rc;
-
- return rc;
+fail:
+ iscsi_conn_failure(conn, rc);
+ return -EIO;
}
static struct iscsi_cls_conn *
@@ -1970,10 +1682,17 @@ free_socket:
/* called with host lock */
static void
-iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
+iscsi_tcp_mtask_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
{
- struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
- tcp_mtask->xmstate = XMSTATE_IMM_HDR_INIT;
+ debug_scsi("mtask deq [cid %d itt 0x%x]\n", conn->id, mtask->itt);
+
+ /* Prepare PDU, optionally w/ immediate data */
+ iscsi_tcp_send_hdr_prep(conn, mtask->hdr, sizeof(*mtask->hdr));
+
+ /* If we have immediate data, attach a payload */
+ if (mtask->data_count)
+ iscsi_tcp_send_linear_data_prepare(conn, mtask->data,
+ mtask->data_count);
}
static int
@@ -2177,7 +1896,7 @@ iscsi_tcp_session_create(struct iscsi_transport *iscsit,
struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
- mtask->hdr = &tcp_mtask->hdr;
+ mtask->hdr = (struct iscsi_hdr *) &tcp_mtask->hdr;
}
if (iscsi_r2tpool_alloc(class_to_transport_session(cls_session)))
@@ -2274,8 +1993,8 @@ static struct iscsi_transport iscsi_tcp_transport = {
/* IO */
.send_pdu = iscsi_conn_send_pdu,
.get_stats = iscsi_conn_get_stats,
- .init_cmd_task = iscsi_tcp_cmd_init,
- .init_mgmt_task = iscsi_tcp_mgmt_init,
+ .init_cmd_task = iscsi_tcp_ctask_init,
+ .init_mgmt_task = iscsi_tcp_mtask_init,
.xmit_cmd_task = iscsi_tcp_ctask_xmit,
.xmit_mgmt_task = iscsi_tcp_mtask_xmit,
.cleanup_cmd_task = iscsi_tcp_cleanup_ctask,