diff options
author | Olaf Kirch <olaf.kirch@oracle.com> | 2007-12-13 12:43:35 -0600 |
---|---|---|
committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2008-01-11 18:28:42 -0600 |
commit | a8ac6311cc21d78fa284cd43f56df2063f536bf1 (patch) | |
tree | c408dcccab2854dd9dd1775b5971ea60b34127dd /drivers/scsi/iscsi_tcp.c | |
parent | 1040c99d9fd9de2bf00efae6d91014f890575bdb (diff) |
[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.c | 1333 |
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; |