Restructure iscsi_tcp_r2t_rsp routine in order to avoid allocating r2t from r2tpool.queue and returning it back in case the parameters rhdr->data_length and or rhdr->data_offset prohibit the requing. Since the values of these parameters are known perior to the allocation than we can do the checking perior the allocation and thus avoid futile allocations.
Signed-off-by: Shlomo Pongratz <[email protected]> --- drivers/scsi/libiscsi_tcp.c | 43 ++++++++++++++++++++++--------------------- 1 files changed, 22 insertions(+), 21 deletions(-) diff --git a/drivers/scsi/libiscsi_tcp.c b/drivers/scsi/libiscsi_tcp.c index 1d58d53..7f59073 100644 --- a/drivers/scsi/libiscsi_tcp.c +++ b/drivers/scsi/libiscsi_tcp.c @@ -529,6 +529,8 @@ static int iscsi_tcp_r2t_rsp(struct iscsi_conn *conn, struct iscsi_task *task) struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr; struct iscsi_r2t_info *r2t; int r2tsn = be32_to_cpu(rhdr->r2tsn); + u32 data_length; + u32 data_offset; int rc; if (tcp_conn->in.datalen) { @@ -554,40 +556,39 @@ static int iscsi_tcp_r2t_rsp(struct iscsi_conn *conn, struct iscsi_task *task) return 0; } - rc = kfifo_out(&tcp_task->r2tpool.queue, (void*)&r2t, sizeof(void*)); - if (!rc) { - iscsi_conn_printk(KERN_ERR, conn, "Could not allocate R2T. " - "Target has sent more R2Ts than it " - "negotiated for or driver has leaked.\n"); - return ISCSI_ERR_PROTO; - } - - r2t->exp_statsn = rhdr->statsn; - r2t->data_length = be32_to_cpu(rhdr->data_length); - if (r2t->data_length == 0) { + data_length = be32_to_cpu(rhdr->data_length); + if (data_length == 0) { iscsi_conn_printk(KERN_ERR, conn, "invalid R2T with zero data len\n"); - kfifo_in(&tcp_task->r2tpool.queue, (void*)&r2t, - sizeof(void*)); return ISCSI_ERR_DATALEN; } - if (r2t->data_length > session->max_burst) + if (data_length > session->max_burst) ISCSI_DBG_TCP(conn, "invalid R2T with data len %u and max " "burst %u. Attempting to execute request.\n", - r2t->data_length, session->max_burst); + data_length, session->max_burst); - r2t->data_offset = be32_to_cpu(rhdr->data_offset); - if (r2t->data_offset + r2t->data_length > scsi_out(task->sc)->length) { + data_offset = be32_to_cpu(rhdr->data_offset); + if (data_offset + data_length > scsi_out(task->sc)->length) { iscsi_conn_printk(KERN_ERR, conn, "invalid R2T with data len %u at offset %u " - "and total length %d\n", r2t->data_length, - r2t->data_offset, scsi_out(task->sc)->length); - kfifo_in(&tcp_task->r2tpool.queue, (void*)&r2t, - sizeof(void*)); + "and total length %d\n", data_length, + data_offset, scsi_out(task->sc)->length); return ISCSI_ERR_DATALEN; } + rc = kfifo_out(&tcp_task->r2tpool.queue, (void*)&r2t, sizeof(void*)); + if (!rc) { + iscsi_conn_printk(KERN_ERR, conn, "Could not allocate R2T. " + "Target has sent more R2Ts than it " + "negotiated for or driver has leaked.\n"); + return ISCSI_ERR_PROTO; + } + + r2t->exp_statsn = rhdr->statsn; + r2t->data_length = data_length; + r2t->data_offset = data_offset; + r2t->ttt = rhdr->ttt; /* no flip */ r2t->datasn = 0; r2t->sent = 0; -- 1.7.1 -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/groups/opt_out.
