Revert "ib_srpt: Convert to percpu_ida tag allocation"
This reverts commit 0fd10721fe3664f7549e74af9d28a509c9a68719.
That patch causes the ib_srpt driver to crash as soon as the first SCSI
command is received:
kernel BUG at drivers/infiniband/ulp/srpt/ib_srpt.c:1439!
invalid opcode: 0000 [#1] SMP
Workqueue: target_completion target_complete_ok_work [target_core_mod]
RIP: srpt_queue_response+0x437/0x4a0 [ib_srpt]
Call Trace:
srpt_queue_data_in+0x9/0x10 [ib_srpt]
target_complete_ok_work+0x152/0x2b0 [target_core_mod]
process_one_work+0x197/0x480
worker_thread+0x49/0x490
kthread+0xea/0x100
ret_from_fork+0x22/0x40
Aside from the crash, the shortcomings of that patch are as follows:
- It makes the ib_srpt driver use I/O contexts allocated by
transport_alloc_session_tags() but it does not initialize these I/O
contexts properly. All the initializations performed by
srpt_alloc_ioctx() are skipped.
- It swaps the order of the send ioctx allocation and the transition to
RTR mode which is wrong.
- The amount of memory that is needed for I/O contexts is doubled.
- srpt_rdma_ch.free_list is no longer used but is not removed.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 0bd3cb2..8b42401 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -1264,26 +1264,40 @@
*/
static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch)
{
- struct se_session *se_sess;
struct srpt_send_ioctx *ioctx;
- int tag;
+ unsigned long flags;
BUG_ON(!ch);
- se_sess = ch->sess;
- tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING);
- if (tag < 0) {
- pr_err("Unable to obtain tag for srpt_send_ioctx\n");
- return NULL;
+ ioctx = NULL;
+ spin_lock_irqsave(&ch->spinlock, flags);
+ if (!list_empty(&ch->free_list)) {
+ ioctx = list_first_entry(&ch->free_list,
+ struct srpt_send_ioctx, free_list);
+ list_del(&ioctx->free_list);
}
- ioctx = &((struct srpt_send_ioctx *)se_sess->sess_cmd_map)[tag];
- memset(ioctx, 0, sizeof(struct srpt_send_ioctx));
- ioctx->ch = ch;
+ spin_unlock_irqrestore(&ch->spinlock, flags);
+
+ if (!ioctx)
+ return ioctx;
+
+ BUG_ON(ioctx->ch != ch);
spin_lock_init(&ioctx->spinlock);
ioctx->state = SRPT_STATE_NEW;
+ ioctx->n_rbuf = 0;
+ ioctx->rbufs = NULL;
+ ioctx->n_rdma = 0;
+ ioctx->n_rdma_wrs = 0;
+ ioctx->rdma_wrs = NULL;
+ ioctx->mapped_sg_count = 0;
init_completion(&ioctx->tx_done);
-
- ioctx->cmd.map_tag = tag;
+ ioctx->queue_status_only = false;
+ /*
+ * transport_init_se_cmd() does not initialize all fields, so do it
+ * here.
+ */
+ memset(&ioctx->cmd, 0, sizeof(ioctx->cmd));
+ memset(&ioctx->sense_data, 0, sizeof(ioctx->sense_data));
return ioctx;
}
@@ -2021,7 +2035,7 @@
struct ib_cm_rep_param *rep_param;
struct srpt_rdma_ch *ch, *tmp_ch;
u32 it_iu_len;
- int ret = 0;
+ int i, ret = 0;
unsigned char *p;
WARN_ON_ONCE(irqs_disabled());
@@ -2143,6 +2157,12 @@
if (!ch->ioctx_ring)
goto free_ch;
+ INIT_LIST_HEAD(&ch->free_list);
+ for (i = 0; i < ch->rq_size; i++) {
+ ch->ioctx_ring[i]->ch = ch;
+ list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list);
+ }
+
ret = srpt_create_ch_ib(ch);
if (ret) {
rej->reason = cpu_to_be32(
@@ -2173,8 +2193,7 @@
p = &ch->sess_name[0];
try_again:
- ch->sess = target_alloc_session(&sport->port_tpg_1, ch->rq_size,
- sizeof(struct srpt_send_ioctx),
+ ch->sess = target_alloc_session(&sport->port_tpg_1, 0, 0,
TARGET_PROT_NORMAL, p, ch, NULL);
if (IS_ERR(ch->sess)) {
pr_info("Rejected login because no ACL has been"
@@ -2881,7 +2900,7 @@
struct srpt_send_ioctx *ioctx = container_of(se_cmd,
struct srpt_send_ioctx, cmd);
struct srpt_rdma_ch *ch = ioctx->ch;
- struct se_session *se_sess = ch->sess;
+ unsigned long flags;
WARN_ON(ioctx->state != SRPT_STATE_DONE);
WARN_ON(ioctx->mapped_sg_count != 0);
@@ -2892,7 +2911,9 @@
ioctx->n_rbuf = 0;
}
- percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
+ spin_lock_irqsave(&ch->spinlock, flags);
+ list_add(&ioctx->free_list, &ch->free_list);
+ spin_unlock_irqrestore(&ch->spinlock, flags);
}
/**