From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
(Add wrapper for handling pending_req tag failure - Juergen)
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Cc: David Vrabel <david.vrabel@xxxxxxxxxx>
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
---
drivers/xen/xen-scsiback.c | 160 ++++++++++++++++++++++++---------------------
1 file changed, 86 insertions(+), 74 deletions(-)
diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c
index a50b6e4..ea3b822 100644
--- a/drivers/xen/xen-scsiback.c
+++ b/drivers/xen/xen-scsiback.c
@@ -190,7 +190,6 @@ module_param_named(max_buffer_pages, scsiback_max_buffer_pages, int, 0644);
MODULE_PARM_DESC(max_buffer_pages,
"Maximum number of free pages to keep in backend buffer");
-static struct kmem_cache *scsiback_cachep;
static DEFINE_SPINLOCK(free_pages_lock);
static int free_pages_num;
static LIST_HEAD(scsiback_free_pages);
@@ -321,11 +320,11 @@ static void scsiback_free_translation_entry(struct kref *kref)
kfree(entry);
}
-static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
- uint32_t resid, struct vscsibk_pend *pending_req)
+static void scsiback_send_response(struct vscsibk_info *info,
+ char *sense_buffer, int32_t result, uint32_t resid,
+ uint16_t rqid)
{
struct vscsiif_response *ring_res;
- struct vscsibk_info *info = pending_req->info;
int notify;
struct scsi_sense_hdr sshdr;
unsigned long flags;
@@ -337,7 +336,7 @@ static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
info->ring.rsp_prod_pvt++;
ring_res->rslt = result;
- ring_res->rqid = pending_req->rqid;
+ ring_res->rqid = rqid;
if (sense_buffer != NULL &&
scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE,
@@ -357,6 +356,13 @@ static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
if (notify)
notify_remote_via_irq(info->irq);
+}
+
+static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
+ uint32_t resid, struct vscsibk_pend *pending_req)
+{
+ scsiback_send_response(pending_req->info, sense_buffer, result,
+ resid, pending_req->rqid);
if (pending_req->v2p)
kref_put(&pending_req->v2p->kref,
@@ -616,15 +622,13 @@ static void scsiback_device_action(struct vscsibk_pend *pending_req,
err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
SUCCESS : FAILED;
+ scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
+ transport_generic_free_cmd(&pending_req->se_cmd, 1);
+ return;
out:
- if (tmr) {
- transport_generic_free_cmd(&pending_req->se_cmd, 1);
+ if (tmr)
kfree(tmr);
- }
-
scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
-
- kmem_cache_free(scsiback_cachep, pending_req);
}
/*
@@ -653,15 +657,53 @@ out:
return entry;
}
-static int prepare_pending_reqs(struct vscsibk_info *info,
- struct vscsiif_request *ring_req,
- struct vscsibk_pend *pending_req)
+static struct vscsibk_pend *scsiback_get_pend_req(struct vscsiif_back_ring *ring,
+ struct v2p_entry *v2p)
+{
+ struct scsiback_tpg *tpg = v2p->tpg;
+ struct scsiback_nexus *nexus = tpg->tpg_nexus;
+ struct se_session *se_sess = nexus->tvn_se_sess;
+ struct vscsibk_pend *req;
+ int tag, i;
+
+ tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING);
+ if (tag < 0) {
+ pr_err("Unable to obtain tag for vscsiif_request\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ req = &((struct vscsibk_pend *)se_sess->sess_cmd_map)[tag];
+ memset(req, 0, sizeof(*req));
+ req->se_cmd.map_tag = tag;
+
+ for (i = 0; i < VSCSI_MAX_GRANTS; i++)
+ req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
+
+ return req;
+}
+
+static struct vscsibk_pend *prepare_pending_reqs(struct vscsibk_info *info,
+ struct vscsiif_back_ring *ring,
+ struct vscsiif_request *ring_req)
{
+ struct vscsibk_pend *pending_req;
struct v2p_entry *v2p;
struct ids_tuple vir;
- pending_req->rqid = ring_req->rqid;
- pending_req->info = info;
+ /* request range check from frontend */
+ if ((ring_req->sc_data_direction != DMA_BIDIRECTIONAL) &&
+ (ring_req->sc_data_direction != DMA_TO_DEVICE) &&
+ (ring_req->sc_data_direction != DMA_FROM_DEVICE) &&
+ (ring_req->sc_data_direction != DMA_NONE)) {
+ pr_debug("invalid parameter data_dir = %d\n",
+ ring_req->sc_data_direction);
+ return ERR_PTR(-EINVAL);
+ }
+ if (ring_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) {
+ pr_debug("invalid parameter cmd_len = %d\n",
+ ring_req->cmd_len);
+ return ERR_PTR(-EINVAL);
+ }
vir.chn = ring_req->channel;
vir.tgt = ring_req->id;
@@ -669,33 +711,24 @@ static int prepare_pending_reqs(struct vscsibk_info *info,
v2p = scsiback_do_translation(info, &vir);
if (!v2p) {
- pending_req->v2p = NULL;
pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n",
- vir.chn, vir.tgt, vir.lun);
- return -ENODEV;
+ vir.chn, vir.tgt, vir.lun);
+ return ERR_PTR(-ENODEV);
}
- pending_req->v2p = v2p;
- /* request range check from frontend */
- pending_req->sc_data_direction = ring_req->sc_data_direction;
- if ((pending_req->sc_data_direction != DMA_BIDIRECTIONAL) &&
- (pending_req->sc_data_direction != DMA_TO_DEVICE) &&
- (pending_req->sc_data_direction != DMA_FROM_DEVICE) &&
- (pending_req->sc_data_direction != DMA_NONE)) {
- pr_debug("invalid parameter data_dir = %d\n",
- pending_req->sc_data_direction);
- return -EINVAL;
+ pending_req = scsiback_get_pend_req(ring, v2p);
+ if (IS_ERR(pending_req)) {
+ kref_put(&v2p->kref, scsiback_free_translation_entry);
+ return ERR_PTR(-ENOMEM);
}
-
+ pending_req->rqid = ring_req->rqid;
+ pending_req->info = info;
+ pending_req->v2p = v2p;
+ pending_req->sc_data_direction = ring_req->sc_data_direction;
pending_req->cmd_len = ring_req->cmd_len;
- if (pending_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) {
- pr_debug("invalid parameter cmd_len = %d\n",
- pending_req->cmd_len);
- return -EINVAL;
- }
memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len);
- return 0;
+ return pending_req;
}
static int scsiback_do_cmd_fn(struct vscsibk_info *info)
@@ -704,7 +737,7 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info)
struct vscsiif_request ring_req;
struct vscsibk_pend *pending_req;
RING_IDX rc, rp;
- int err, more_to_do;
+ int more_to_do;
uint32_t result;
rc = ring->req_cons;
@@ -722,16 +755,13 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info)
while ((rc != rp)) {
if (RING_REQUEST_CONS_OVERFLOW(ring, rc))
break;
- pending_req = kmem_cache_alloc(scsiback_cachep, GFP_KERNEL);
- if (!pending_req)
- return 1;
RING_COPY_REQUEST(ring, rc, &ring_req);
ring->req_cons = ++rc;
- err = prepare_pending_reqs(info, &ring_req, pending_req);
- if (err) {
- switch (err) {
+ pending_req = prepare_pending_reqs(info, ring, &ring_req);
+ if (IS_ERR(pending_req)) {
+ switch (PTR_ERR(pending_req)) {
case -ENODEV:
result = DID_NO_CONNECT;
break;
@@ -739,9 +769,8 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info)
result = DRIVER_ERROR;
break;
}
- scsiback_do_resp_with_sense(NULL, result << 24, 0,
- pending_req);
- kmem_cache_free(scsiback_cachep, pending_req);
+ scsiback_send_response(info, NULL, result << 24, 0,
+ ring_req.rqid);
return 1;
}
@@ -750,8 +779,8 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info)
if (scsiback_gnttab_data_map(&ring_req, pending_req)) {
scsiback_fast_flush_area(pending_req);
scsiback_do_resp_with_sense(NULL,
- DRIVER_ERROR << 24, 0, pending_req);
- kmem_cache_free(scsiback_cachep, pending_req);
+ DRIVER_ERROR << 24, 0, pending_req);
+ transport_generic_free_cmd(&pending_req->se_cmd, 0);
} else {
scsiback_cmd_exec(pending_req);
}
@@ -765,9 +794,9 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info)
break;
default:
pr_err_ratelimited("invalid request\n");
- scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24,
- 0, pending_req);
- kmem_cache_free(scsiback_cachep, pending_req);
+ scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24, 0,
+ pending_req);
+ transport_generic_free_cmd(&pending_req->se_cmd, 0);
break;
}
@@ -1355,10 +1384,9 @@ static int scsiback_check_stop_free(struct se_cmd *se_cmd)
static void scsiback_release_cmd(struct se_cmd *se_cmd)
{
- struct vscsibk_pend *pending_req = container_of(se_cmd,
- struct vscsibk_pend, se_cmd);
+ struct se_session *se_sess = se_cmd->se_sess;
- kmem_cache_free(scsiback_cachep, pending_req);
+ percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
}
static int scsiback_shutdown_session(struct se_session *se_sess)
@@ -1501,7 +1529,8 @@ static int scsiback_make_nexus(struct scsiback_tpg *tpg,
goto out_unlock;
}
- tv_nexus->tvn_se_sess = target_alloc_session(&tpg->se_tpg, 0, 0,
+ tv_nexus->tvn_se_sess = target_alloc_session(&tpg->se_tpg, 128,
+ sizeof(struct vscsibk_pend),
TARGET_PROT_NORMAL, name,
tv_nexus, NULL);
if (IS_ERR(tv_nexus->tvn_se_sess)) {
@@ -1831,16 +1860,6 @@ static struct xenbus_driver scsiback_driver = {
.otherend_changed = scsiback_frontend_changed
};
-static void scsiback_init_pend(void *p)
-{
- struct vscsibk_pend *pend = p;
- int i;
-
- memset(pend, 0, sizeof(*pend));
- for (i = 0; i < VSCSI_MAX_GRANTS; i++)
- pend->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
-}
-
static int __init scsiback_init(void)
{
int ret;
@@ -1851,14 +1870,9 @@ static int __init scsiback_init(void)
pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n",
VSCSI_VERSION, utsname()->sysname, utsname()->machine);
- scsiback_cachep = kmem_cache_create("vscsiif_cache",
- sizeof(struct vscsibk_pend), 0, 0, scsiback_init_pend);
- if (!scsiback_cachep)
- return -ENOMEM;
-
ret = xenbus_register_backend(&scsiback_driver);
if (ret)
- goto out_cache_destroy;
+ goto out;
ret = target_register_template(&scsiback_ops);
if (ret)
@@ -1868,8 +1882,7 @@ static int __init scsiback_init(void)
out_unregister_xenbus:
xenbus_unregister_driver(&scsiback_driver);
-out_cache_destroy:
- kmem_cache_destroy(scsiback_cachep);
+out:
pr_err("%s: error %d\n", __func__, ret);
return ret;
}
@@ -1885,7 +1898,6 @@ static void __exit scsiback_exit(void)
}
target_unregister_template(&scsiback_ops);
xenbus_unregister_driver(&scsiback_driver);
- kmem_cache_destroy(scsiback_cachep);
}
module_init(scsiback_init);
--
1.9.1
--
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