aboutsummaryrefslogtreecommitdiff
path: root/drivers/block
diff options
context:
space:
mode:
authorLinus Torvalds2021-09-02 13:20:11 -0700
committerLinus Torvalds2021-09-02 13:20:11 -0700
commit9ae5fceb9a20154d74586fe17d1096b981b23e34 (patch)
treef11664ab46a7b6b4b9c07f41f5b509500705d1c8 /drivers/block
parenta2d616b935a0df24bc9375785b19bf30d7fc9c6a (diff)
parent58e636039b512697554b579c2bb23774061877f5 (diff)
Merge tag 'for-linus-5.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross: - some small cleanups - a fix for a bug when running as Xen PV guest which could result in not all memory being transferred in case of a migration of the guest - a small series for getting rid of code for supporting very old Xen hypervisor versions nobody should be using since many years now - a series for hardening the Xen block frontend driver - a fix for Xen PV boot code issuing warning messages due to a stray preempt_disable() on the non-boot processors * tag 'for-linus-5.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: remove stray preempt_disable() from PV AP startup code xen/pcifront: Removed unnecessary __ref annotation x86: xen: platform-pci-unplug: use pr_err() and pr_warn() instead of raw printk() drivers/xen/xenbus/xenbus_client.c: fix bugon.cocci warnings xen/blkfront: don't trust the backend response data blindly xen/blkfront: don't take local copy of a request from the ring page xen/blkfront: read response from backend only once xen: assume XENFEAT_gnttab_map_avail_bits being set for pv guests xen: assume XENFEAT_mmu_pt_update_preserve_ad being set for pv guests xen: check required Xen features xen: fix setting of max_pfn in shared_info
Diffstat (limited to 'drivers/block')
-rw-r--r--drivers/block/xen-blkfront.c126
1 files changed, 84 insertions, 42 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 715bfa8aca7f..72902104f111 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -80,6 +80,7 @@ enum blkif_state {
BLKIF_STATE_DISCONNECTED,
BLKIF_STATE_CONNECTED,
BLKIF_STATE_SUSPENDED,
+ BLKIF_STATE_ERROR,
};
struct grant {
@@ -89,6 +90,7 @@ struct grant {
};
enum blk_req_status {
+ REQ_PROCESSING,
REQ_WAITING,
REQ_DONE,
REQ_ERROR,
@@ -530,10 +532,10 @@ static unsigned long blkif_ring_get_request(struct blkfront_ring_info *rinfo,
id = get_id_from_freelist(rinfo);
rinfo->shadow[id].request = req;
- rinfo->shadow[id].status = REQ_WAITING;
+ rinfo->shadow[id].status = REQ_PROCESSING;
rinfo->shadow[id].associated_id = NO_ASSOCIATED_ID;
- (*ring_req)->u.rw.id = id;
+ rinfo->shadow[id].req.u.rw.id = id;
return id;
}
@@ -541,11 +543,12 @@ static unsigned long blkif_ring_get_request(struct blkfront_ring_info *rinfo,
static int blkif_queue_discard_req(struct request *req, struct blkfront_ring_info *rinfo)
{
struct blkfront_info *info = rinfo->dev_info;
- struct blkif_request *ring_req;
+ struct blkif_request *ring_req, *final_ring_req;
unsigned long id;
/* Fill out a communications ring structure. */
- id = blkif_ring_get_request(rinfo, req, &ring_req);
+ id = blkif_ring_get_request(rinfo, req, &final_ring_req);
+ ring_req = &rinfo->shadow[id].req;
ring_req->operation = BLKIF_OP_DISCARD;
ring_req->u.discard.nr_sectors = blk_rq_sectors(req);
@@ -556,8 +559,9 @@ static int blkif_queue_discard_req(struct request *req, struct blkfront_ring_inf
else
ring_req->u.discard.flag = 0;
- /* Keep a private copy so we can reissue requests when recovering. */
- rinfo->shadow[id].req = *ring_req;
+ /* Copy the request to the ring page. */
+ *final_ring_req = *ring_req;
+ rinfo->shadow[id].status = REQ_WAITING;
return 0;
}
@@ -690,6 +694,7 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
{
struct blkfront_info *info = rinfo->dev_info;
struct blkif_request *ring_req, *extra_ring_req = NULL;
+ struct blkif_request *final_ring_req, *final_extra_ring_req = NULL;
unsigned long id, extra_id = NO_ASSOCIATED_ID;
bool require_extra_req = false;
int i;
@@ -734,7 +739,8 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
}
/* Fill out a communications ring structure. */
- id = blkif_ring_get_request(rinfo, req, &ring_req);
+ id = blkif_ring_get_request(rinfo, req, &final_ring_req);
+ ring_req = &rinfo->shadow[id].req;
num_sg = blk_rq_map_sg(req->q, req, rinfo->shadow[id].sg);
num_grant = 0;
@@ -785,7 +791,9 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
ring_req->u.rw.nr_segments = num_grant;
if (unlikely(require_extra_req)) {
extra_id = blkif_ring_get_request(rinfo, req,
- &extra_ring_req);
+ &final_extra_ring_req);
+ extra_ring_req = &rinfo->shadow[extra_id].req;
+
/*
* Only the first request contains the scatter-gather
* list.
@@ -827,10 +835,13 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
if (setup.segments)
kunmap_atomic(setup.segments);
- /* Keep a private copy so we can reissue requests when recovering. */
- rinfo->shadow[id].req = *ring_req;
- if (unlikely(require_extra_req))
- rinfo->shadow[extra_id].req = *extra_ring_req;
+ /* Copy request(s) to the ring page. */
+ *final_ring_req = *ring_req;
+ rinfo->shadow[id].status = REQ_WAITING;
+ if (unlikely(require_extra_req)) {
+ *final_extra_ring_req = *extra_ring_req;
+ rinfo->shadow[extra_id].status = REQ_WAITING;
+ }
if (new_persistent_gnts)
gnttab_free_grant_references(setup.gref_head);
@@ -1353,8 +1364,8 @@ static enum blk_req_status blkif_rsp_to_req_status(int rsp)
static int blkif_get_final_status(enum blk_req_status s1,
enum blk_req_status s2)
{
- BUG_ON(s1 == REQ_WAITING);
- BUG_ON(s2 == REQ_WAITING);
+ BUG_ON(s1 < REQ_DONE);
+ BUG_ON(s2 < REQ_DONE);
if (s1 == REQ_ERROR || s2 == REQ_ERROR)
return BLKIF_RSP_ERROR;
@@ -1387,7 +1398,7 @@ static bool blkif_completion(unsigned long *id,
s->status = blkif_rsp_to_req_status(bret->status);
/* Wait the second response if not yet here. */
- if (s2->status == REQ_WAITING)
+ if (s2->status < REQ_DONE)
return false;
bret->status = blkif_get_final_status(s->status,
@@ -1495,7 +1506,7 @@ static bool blkif_completion(unsigned long *id,
static irqreturn_t blkif_interrupt(int irq, void *dev_id)
{
struct request *req;
- struct blkif_response *bret;
+ struct blkif_response bret;
RING_IDX i, rp;
unsigned long flags;
struct blkfront_ring_info *rinfo = (struct blkfront_ring_info *)dev_id;
@@ -1506,54 +1517,76 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
spin_lock_irqsave(&rinfo->ring_lock, flags);
again:
- rp = rinfo->ring.sring->rsp_prod;
- rmb(); /* Ensure we see queued responses up to 'rp'. */
+ rp = READ_ONCE(rinfo->ring.sring->rsp_prod);
+ virt_rmb(); /* Ensure we see queued responses up to 'rp'. */
+ if (RING_RESPONSE_PROD_OVERFLOW(&rinfo->ring, rp)) {
+ pr_alert("%s: illegal number of responses %u\n",
+ info->gd->disk_name, rp - rinfo->ring.rsp_cons);
+ goto err;
+ }
for (i = rinfo->ring.rsp_cons; i != rp; i++) {
unsigned long id;
+ unsigned int op;
+
+ RING_COPY_RESPONSE(&rinfo->ring, i, &bret);
+ id = bret.id;
- bret = RING_GET_RESPONSE(&rinfo->ring, i);
- id = bret->id;
/*
* The backend has messed up and given us an id that we would
* never have given to it (we stamp it up to BLK_RING_SIZE -
* look in get_id_from_freelist.
*/
if (id >= BLK_RING_SIZE(info)) {
- WARN(1, "%s: response to %s has incorrect id (%ld)\n",
- info->gd->disk_name, op_name(bret->operation), id);
- /* We can't safely get the 'struct request' as
- * the id is busted. */
- continue;
+ pr_alert("%s: response has incorrect id (%ld)\n",
+ info->gd->disk_name, id);
+ goto err;
}
+ if (rinfo->shadow[id].status != REQ_WAITING) {
+ pr_alert("%s: response references no pending request\n",
+ info->gd->disk_name);
+ goto err;
+ }
+
+ rinfo->shadow[id].status = REQ_PROCESSING;
req = rinfo->shadow[id].request;
- if (bret->operation != BLKIF_OP_DISCARD) {
+ op = rinfo->shadow[id].req.operation;
+ if (op == BLKIF_OP_INDIRECT)
+ op = rinfo->shadow[id].req.u.indirect.indirect_op;
+ if (bret.operation != op) {
+ pr_alert("%s: response has wrong operation (%u instead of %u)\n",
+ info->gd->disk_name, bret.operation, op);
+ goto err;
+ }
+
+ if (bret.operation != BLKIF_OP_DISCARD) {
/*
* We may need to wait for an extra response if the
* I/O request is split in 2
*/
- if (!blkif_completion(&id, rinfo, bret))
+ if (!blkif_completion(&id, rinfo, &bret))
continue;
}
if (add_id_to_freelist(rinfo, id)) {
WARN(1, "%s: response to %s (id %ld) couldn't be recycled!\n",
- info->gd->disk_name, op_name(bret->operation), id);
+ info->gd->disk_name, op_name(bret.operation), id);
continue;
}
- if (bret->status == BLKIF_RSP_OKAY)
+ if (bret.status == BLKIF_RSP_OKAY)
blkif_req(req)->error = BLK_STS_OK;
else
blkif_req(req)->error = BLK_STS_IOERR;
- switch (bret->operation) {
+ switch (bret.operation) {
case BLKIF_OP_DISCARD:
- if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) {
+ if (unlikely(bret.status == BLKIF_RSP_EOPNOTSUPP)) {
struct request_queue *rq = info->rq;
- printk(KERN_WARNING "blkfront: %s: %s op failed\n",
- info->gd->disk_name, op_name(bret->operation));
+
+ pr_warn_ratelimited("blkfront: %s: %s op failed\n",
+ info->gd->disk_name, op_name(bret.operation));
blkif_req(req)->error = BLK_STS_NOTSUPP;
info->feature_discard = 0;
info->feature_secdiscard = 0;
@@ -1563,15 +1596,15 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
break;
case BLKIF_OP_FLUSH_DISKCACHE:
case BLKIF_OP_WRITE_BARRIER:
- if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) {
- printk(KERN_WARNING "blkfront: %s: %s op failed\n",
- info->gd->disk_name, op_name(bret->operation));
+ if (unlikely(bret.status == BLKIF_RSP_EOPNOTSUPP)) {
+ pr_warn_ratelimited("blkfront: %s: %s op failed\n",
+ info->gd->disk_name, op_name(bret.operation));
blkif_req(req)->error = BLK_STS_NOTSUPP;
}
- if (unlikely(bret->status == BLKIF_RSP_ERROR &&
+ if (unlikely(bret.status == BLKIF_RSP_ERROR &&
rinfo->shadow[id].req.u.rw.nr_segments == 0)) {
- printk(KERN_WARNING "blkfront: %s: empty %s op failed\n",
- info->gd->disk_name, op_name(bret->operation));
+ pr_warn_ratelimited("blkfront: %s: empty %s op failed\n",
+ info->gd->disk_name, op_name(bret.operation));
blkif_req(req)->error = BLK_STS_NOTSUPP;
}
if (unlikely(blkif_req(req)->error)) {
@@ -1584,9 +1617,10 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
fallthrough;
case BLKIF_OP_READ:
case BLKIF_OP_WRITE:
- if (unlikely(bret->status != BLKIF_RSP_OKAY))
- dev_dbg(&info->xbdev->dev, "Bad return from blkdev data "
- "request: %x\n", bret->status);
+ if (unlikely(bret.status != BLKIF_RSP_OKAY))
+ dev_dbg_ratelimited(&info->xbdev->dev,
+ "Bad return from blkdev data request: %#x\n",
+ bret.status);
break;
default:
@@ -1612,6 +1646,14 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
spin_unlock_irqrestore(&rinfo->ring_lock, flags);
return IRQ_HANDLED;
+
+ err:
+ info->connected = BLKIF_STATE_ERROR;
+
+ spin_unlock_irqrestore(&rinfo->ring_lock, flags);
+
+ pr_alert("%s disabled for further use\n", info->gd->disk_name);
+ return IRQ_HANDLED;
}