hugetlbfs-flush-tlbs-correctly-after-huge_pmd_unshare.patch
nfc-add-nci_unreg-flag-to-eliminate-the-race.patch
fuse-release-pipe-buf-after-last-use.patch
+xen-sync-include-xen-interface-io-ring.h-with-xen-s-newest-version.patch
+xen-blkfront-read-response-from-backend-only-once.patch
+xen-blkfront-don-t-take-local-copy-of-a-request-from-the-ring-page.patch
+xen-blkfront-don-t-trust-the-backend-response-data-blindly.patch
+xen-netfront-read-response-from-backend-only-once.patch
+xen-netfront-don-t-read-data-from-request-on-the-ring-page.patch
+xen-netfront-disentangle-tx_skb_freelist.patch
+xen-netfront-don-t-trust-the-backend-response-data-blindly.patch
+tty-hvc-replace-bug_on-with-negative-return-value.patch
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 10:45:11 +0100
+Subject: tty: hvc: replace BUG_ON() with negative return value
+
+From: Juergen Gross <jgross@suse.com>
+
+commit e679004dec37566f658a255157d3aed9d762a2b7 upstream.
+
+Xen frontends shouldn't BUG() in case of illegal data received from
+their backends. So replace the BUG_ON()s when reading illegal data from
+the ring page with negative return values.
+
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Link: https://lore.kernel.org/r/20210707091045.460-1-jgross@suse.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/tty/hvc/hvc_xen.c | 17 ++++++++++++++---
+ 1 file changed, 14 insertions(+), 3 deletions(-)
+
+--- a/drivers/tty/hvc/hvc_xen.c
++++ b/drivers/tty/hvc/hvc_xen.c
+@@ -86,7 +86,11 @@ static int __write_console(struct xencon
+ cons = intf->out_cons;
+ prod = intf->out_prod;
+ mb(); /* update queue values before going on */
+- BUG_ON((prod - cons) > sizeof(intf->out));
++
++ if ((prod - cons) > sizeof(intf->out)) {
++ pr_err_once("xencons: Illegal ring page indices");
++ return -EINVAL;
++ }
+
+ while ((sent < len) && ((prod - cons) < sizeof(intf->out)))
+ intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++];
+@@ -114,7 +118,10 @@ static int domU_write_console(uint32_t v
+ */
+ while (len) {
+ int sent = __write_console(cons, data, len);
+-
++
++ if (sent < 0)
++ return sent;
++
+ data += sent;
+ len -= sent;
+
+@@ -138,7 +145,11 @@ static int domU_read_console(uint32_t vt
+ cons = intf->in_cons;
+ prod = intf->in_prod;
+ mb(); /* get pointers before reading ring */
+- BUG_ON((prod - cons) > sizeof(intf->in));
++
++ if ((prod - cons) > sizeof(intf->in)) {
++ pr_err_once("xencons: Illegal ring page indices");
++ return -EINVAL;
++ }
+
+ while (cons != prod && recv < len)
+ buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)];
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 08:45:38 +0100
+Subject: xen/blkfront: don't take local copy of a request from the ring page
+
+From: Juergen Gross <jgross@suse.com>
+
+commit 8f5a695d99000fc3aa73934d7ced33cfc64dcdab upstream.
+
+In order to avoid a malicious backend being able to influence the local
+copy of a request build the request locally first and then copy it to
+the ring page instead of doing it the other way round as today.
+
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Acked-by: Roger Pau Monné <roger.pau@citrix.com>
+Link: https://lore.kernel.org/r/20210730103854.12681-3-jgross@suse.com
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/block/xen-blkfront.c | 25 +++++++++++++++----------
+ 1 file changed, 15 insertions(+), 10 deletions(-)
+
+--- a/drivers/block/xen-blkfront.c
++++ b/drivers/block/xen-blkfront.c
+@@ -536,7 +536,7 @@ static unsigned long blkif_ring_get_requ
+ rinfo->shadow[id].status = REQ_WAITING;
+ rinfo->shadow[id].associated_id = NO_ASSOCIATED_ID;
+
+- (*ring_req)->u.rw.id = id;
++ rinfo->shadow[id].req.u.rw.id = id;
+
+ return id;
+ }
+@@ -544,11 +544,12 @@ static unsigned long blkif_ring_get_requ
+ 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);
+@@ -559,8 +560,8 @@ static int blkif_queue_discard_req(struc
+ 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;
+
+ return 0;
+ }
+@@ -693,6 +694,7 @@ static int blkif_queue_rw_req(struct req
+ {
+ 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;
+@@ -737,7 +739,8 @@ static int blkif_queue_rw_req(struct req
+ }
+
+ /* 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;
+@@ -788,7 +791,9 @@ static int blkif_queue_rw_req(struct req
+ 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.
+@@ -830,10 +835,10 @@ static int blkif_queue_rw_req(struct req
+ if (setup.segments)
+ kunmap_atomic(setup.segments);
+
+- /* Keep a private copy so we can reissue requests when recovering. */
+- rinfo->shadow[id].req = *ring_req;
++ /* Copy request(s) to the ring page. */
++ *final_ring_req = *ring_req;
+ if (unlikely(require_extra_req))
+- rinfo->shadow[extra_id].req = *extra_ring_req;
++ *final_extra_ring_req = *extra_ring_req;
+
+ if (new_persistent_gnts)
+ gnttab_free_grant_references(setup.gref_head);
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 08:47:08 +0100
+Subject: xen/blkfront: don't trust the backend response data blindly
+
+From: Juergen Gross <jgross@suse.com>
+
+commit b94e4b147fd1992ad450e1fea1fdaa3738753373 upstream.
+
+Today blkfront will trust the backend to send only sane response data.
+In order to avoid privilege escalations or crashes in case of malicious
+backends verify the data to be within expected limits. Especially make
+sure that the response always references an outstanding request.
+
+Introduce a new state of the ring BLKIF_STATE_ERROR which will be
+switched to in case an inconsistency is being detected. Recovering from
+this state is possible only via removing and adding the virtual device
+again (e.g. via a suspend/resume cycle).
+
+Make all warning messages issued due to valid error responses rate
+limited in order to avoid message floods being triggered by a malicious
+backend.
+
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Acked-by: Roger Pau Monné <roger.pau@citrix.com>
+Link: https://lore.kernel.org/r/20210730103854.12681-4-jgross@suse.com
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/block/xen-blkfront.c | 70 ++++++++++++++++++++++++++++++++-----------
+ 1 file changed, 53 insertions(+), 17 deletions(-)
+
+--- 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,
+@@ -533,7 +535,7 @@ static unsigned long blkif_ring_get_requ
+
+ 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;
+
+ rinfo->shadow[id].req.u.rw.id = id;
+@@ -562,6 +564,7 @@ static int blkif_queue_discard_req(struc
+
+ /* Copy the request to the ring page. */
+ *final_ring_req = *ring_req;
++ rinfo->shadow[id].status = REQ_WAITING;
+
+ return 0;
+ }
+@@ -837,8 +840,11 @@ static int blkif_queue_rw_req(struct req
+
+ /* Copy request(s) to the ring page. */
+ *final_ring_req = *ring_req;
+- if (unlikely(require_extra_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);
+@@ -1412,8 +1418,8 @@ static enum blk_req_status blkif_rsp_to_
+ 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;
+@@ -1446,7 +1452,7 @@ static bool blkif_completion(unsigned lo
+ 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,
+@@ -1565,11 +1571,17 @@ static irqreturn_t blkif_interrupt(int i
+
+ 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;
+@@ -1580,14 +1592,28 @@ static irqreturn_t blkif_interrupt(int i
+ * 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;
+
++ 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
+@@ -1612,7 +1638,8 @@ static irqreturn_t blkif_interrupt(int i
+ case BLKIF_OP_DISCARD:
+ if (unlikely(bret.status == BLKIF_RSP_EOPNOTSUPP)) {
+ struct request_queue *rq = info->rq;
+- printk(KERN_WARNING "blkfront: %s: %s op failed\n",
++
++ 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;
+@@ -1624,13 +1651,13 @@ static irqreturn_t blkif_interrupt(int i
+ 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",
++ 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 &&
+ rinfo->shadow[id].req.u.rw.nr_segments == 0)) {
+- printk(KERN_WARNING "blkfront: %s: empty %s op failed\n",
++ 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;
+ }
+@@ -1645,8 +1672,9 @@ static irqreturn_t blkif_interrupt(int i
+ 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);
++ dev_dbg_ratelimited(&info->xbdev->dev,
++ "Bad return from blkdev data request: %#x\n",
++ bret.status);
+
+ break;
+ default:
+@@ -1671,6 +1699,14 @@ static irqreturn_t blkif_interrupt(int i
+ 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;
+ }
+
+
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 08:41:07 +0100
+Subject: xen/blkfront: read response from backend only once
+
+From: Juergen Gross <jgross@suse.com>
+
+commit 71b66243f9898d0e54296b4e7035fb33cdcb0707 upstream.
+
+In order to avoid problems in case the backend is modifying a response
+on the ring page while the frontend has already seen it, just read the
+response into a local buffer in one go and then operate on that buffer
+only.
+
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Acked-by: Roger Pau Monné <roger.pau@citrix.com>
+Link: https://lore.kernel.org/r/20210730103854.12681-2-jgross@suse.com
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/block/xen-blkfront.c | 35 ++++++++++++++++++-----------------
+ 1 file changed, 18 insertions(+), 17 deletions(-)
+
+--- a/drivers/block/xen-blkfront.c
++++ b/drivers/block/xen-blkfront.c
+@@ -1549,7 +1549,7 @@ static bool blkif_completion(unsigned lo
+ 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;
+@@ -1566,8 +1566,9 @@ static irqreturn_t blkif_interrupt(int i
+ for (i = rinfo->ring.rsp_cons; i != rp; i++) {
+ unsigned long id;
+
+- bret = RING_GET_RESPONSE(&rinfo->ring, i);
+- id = bret->id;
++ RING_COPY_RESPONSE(&rinfo->ring, i, &bret);
++ 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 -
+@@ -1575,39 +1576,39 @@ static irqreturn_t blkif_interrupt(int i
+ */
+ 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);
++ info->gd->disk_name, op_name(bret.operation), id);
+ /* We can't safely get the 'struct request' as
+ * the id is busted. */
+ continue;
+ }
+ req = rinfo->shadow[id].request;
+
+- if (bret->operation != BLKIF_OP_DISCARD) {
++ 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));
++ info->gd->disk_name, op_name(bret.operation));
+ blkif_req(req)->error = BLK_STS_NOTSUPP;
+ info->feature_discard = 0;
+ info->feature_secdiscard = 0;
+@@ -1617,15 +1618,15 @@ static irqreturn_t blkif_interrupt(int i
+ break;
+ case BLKIF_OP_FLUSH_DISKCACHE:
+ case BLKIF_OP_WRITE_BARRIER:
+- if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) {
++ if (unlikely(bret.status == BLKIF_RSP_EOPNOTSUPP)) {
+ printk(KERN_WARNING "blkfront: %s: %s op failed\n",
+- info->gd->disk_name, op_name(bret->operation));
++ 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));
++ info->gd->disk_name, op_name(bret.operation));
+ blkif_req(req)->error = BLK_STS_NOTSUPP;
+ }
+ if (unlikely(blkif_req(req)->error)) {
+@@ -1638,9 +1639,9 @@ static irqreturn_t blkif_interrupt(int i
+ /* fall through */
+ case BLKIF_OP_READ:
+ case BLKIF_OP_WRITE:
+- if (unlikely(bret->status != BLKIF_RSP_OKAY))
++ if (unlikely(bret.status != BLKIF_RSP_OKAY))
+ dev_dbg(&info->xbdev->dev, "Bad return from blkdev data "
+- "request: %x\n", bret->status);
++ "request: %x\n", bret.status);
+
+ break;
+ default:
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 10:43:35 +0100
+Subject: xen/netfront: disentangle tx_skb_freelist
+
+From: Juergen Gross <jgross@suse.com>
+
+commit 21631d2d741a64a073e167c27769e73bc7844a2f upstream.
+
+The tx_skb_freelist elements are in a single linked list with the
+request id used as link reference. The per element link field is in a
+union with the skb pointer of an in use request.
+
+Move the link reference out of the union in order to enable a later
+reuse of it for requests which need a populated skb pointer.
+
+Rename add_id_to_freelist() and get_id_from_freelist() to
+add_id_to_list() and get_id_from_list() in order to prepare using
+those for other lists as well. Define ~0 as value to indicate the end
+of a list and place that value into the link for a request not being
+on the list.
+
+When freeing a skb zero the skb pointer in the request. Use a NULL
+value of the skb pointer instead of skb_entry_is_link() for deciding
+whether a request has a skb linked to it.
+
+Remove skb_entry_set_link() and open code it instead as it is really
+trivial now.
+
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/xen-netfront.c | 61 ++++++++++++++++++---------------------------
+ 1 file changed, 25 insertions(+), 36 deletions(-)
+
+--- a/drivers/net/xen-netfront.c
++++ b/drivers/net/xen-netfront.c
+@@ -121,17 +121,11 @@ struct netfront_queue {
+
+ /*
+ * {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries
+- * are linked from tx_skb_freelist through skb_entry.link.
+- *
+- * NB. Freelist index entries are always going to be less than
+- * PAGE_OFFSET, whereas pointers to skbs will always be equal or
+- * greater than PAGE_OFFSET: we use this property to distinguish
+- * them.
++ * are linked from tx_skb_freelist through tx_link.
+ */
+- union skb_entry {
+- struct sk_buff *skb;
+- unsigned long link;
+- } tx_skbs[NET_TX_RING_SIZE];
++ struct sk_buff *tx_skbs[NET_TX_RING_SIZE];
++ unsigned short tx_link[NET_TX_RING_SIZE];
++#define TX_LINK_NONE 0xffff
+ grant_ref_t gref_tx_head;
+ grant_ref_t grant_tx_ref[NET_TX_RING_SIZE];
+ struct page *grant_tx_page[NET_TX_RING_SIZE];
+@@ -169,33 +163,25 @@ struct netfront_rx_info {
+ struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
+ };
+
+-static void skb_entry_set_link(union skb_entry *list, unsigned short id)
+-{
+- list->link = id;
+-}
+-
+-static int skb_entry_is_link(const union skb_entry *list)
+-{
+- BUILD_BUG_ON(sizeof(list->skb) != sizeof(list->link));
+- return (unsigned long)list->skb < PAGE_OFFSET;
+-}
+-
+ /*
+ * Access macros for acquiring freeing slots in tx_skbs[].
+ */
+
+-static void add_id_to_freelist(unsigned *head, union skb_entry *list,
+- unsigned short id)
++static void add_id_to_list(unsigned *head, unsigned short *list,
++ unsigned short id)
+ {
+- skb_entry_set_link(&list[id], *head);
++ list[id] = *head;
+ *head = id;
+ }
+
+-static unsigned short get_id_from_freelist(unsigned *head,
+- union skb_entry *list)
++static unsigned short get_id_from_list(unsigned *head, unsigned short *list)
+ {
+ unsigned int id = *head;
+- *head = list[id].link;
++
++ if (id != TX_LINK_NONE) {
++ *head = list[id];
++ list[id] = TX_LINK_NONE;
++ }
+ return id;
+ }
+
+@@ -396,7 +382,8 @@ static void xennet_tx_buf_gc(struct netf
+ continue;
+
+ id = txrsp.id;
+- skb = queue->tx_skbs[id].skb;
++ skb = queue->tx_skbs[id];
++ queue->tx_skbs[id] = NULL;
+ if (unlikely(gnttab_query_foreign_access(
+ queue->grant_tx_ref[id]) != 0)) {
+ pr_alert("%s: warning -- grant still in use by backend domain\n",
+@@ -409,7 +396,7 @@ static void xennet_tx_buf_gc(struct netf
+ &queue->gref_tx_head, queue->grant_tx_ref[id]);
+ queue->grant_tx_ref[id] = GRANT_INVALID_REF;
+ queue->grant_tx_page[id] = NULL;
+- add_id_to_freelist(&queue->tx_skb_freelist, queue->tx_skbs, id);
++ add_id_to_list(&queue->tx_skb_freelist, queue->tx_link, id);
+ dev_kfree_skb_irq(skb);
+ }
+
+@@ -442,7 +429,7 @@ static void xennet_tx_setup_grant(unsign
+ struct netfront_queue *queue = info->queue;
+ struct sk_buff *skb = info->skb;
+
+- id = get_id_from_freelist(&queue->tx_skb_freelist, queue->tx_skbs);
++ id = get_id_from_list(&queue->tx_skb_freelist, queue->tx_link);
+ tx = RING_GET_REQUEST(&queue->tx, queue->tx.req_prod_pvt++);
+ ref = gnttab_claim_grant_reference(&queue->gref_tx_head);
+ WARN_ON_ONCE(IS_ERR_VALUE((unsigned long)(int)ref));
+@@ -450,7 +437,7 @@ static void xennet_tx_setup_grant(unsign
+ gnttab_grant_foreign_access_ref(ref, queue->info->xbdev->otherend_id,
+ gfn, GNTMAP_readonly);
+
+- queue->tx_skbs[id].skb = skb;
++ queue->tx_skbs[id] = skb;
+ queue->grant_tx_page[id] = page;
+ queue->grant_tx_ref[id] = ref;
+
+@@ -1132,17 +1119,18 @@ static void xennet_release_tx_bufs(struc
+
+ for (i = 0; i < NET_TX_RING_SIZE; i++) {
+ /* Skip over entries which are actually freelist references */
+- if (skb_entry_is_link(&queue->tx_skbs[i]))
++ if (!queue->tx_skbs[i])
+ continue;
+
+- skb = queue->tx_skbs[i].skb;
++ skb = queue->tx_skbs[i];
++ queue->tx_skbs[i] = NULL;
+ get_page(queue->grant_tx_page[i]);
+ gnttab_end_foreign_access(queue->grant_tx_ref[i],
+ GNTMAP_readonly,
+ (unsigned long)page_address(queue->grant_tx_page[i]));
+ queue->grant_tx_page[i] = NULL;
+ queue->grant_tx_ref[i] = GRANT_INVALID_REF;
+- add_id_to_freelist(&queue->tx_skb_freelist, queue->tx_skbs, i);
++ add_id_to_list(&queue->tx_skb_freelist, queue->tx_link, i);
+ dev_kfree_skb_irq(skb);
+ }
+ }
+@@ -1624,13 +1612,14 @@ static int xennet_init_queue(struct netf
+ snprintf(queue->name, sizeof(queue->name), "vif%s-q%u",
+ devid, queue->id);
+
+- /* Initialise tx_skbs as a free chain containing every entry. */
++ /* Initialise tx_skb_freelist as a free chain containing every entry. */
+ queue->tx_skb_freelist = 0;
+ for (i = 0; i < NET_TX_RING_SIZE; i++) {
+- skb_entry_set_link(&queue->tx_skbs[i], i+1);
++ queue->tx_link[i] = i + 1;
+ queue->grant_tx_ref[i] = GRANT_INVALID_REF;
+ queue->grant_tx_page[i] = NULL;
+ }
++ queue->tx_link[NET_TX_RING_SIZE - 1] = TX_LINK_NONE;
+
+ /* Clear out rx_skbs */
+ for (i = 0; i < NET_RX_RING_SIZE; i++) {
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 10:38:28 +0100
+Subject: xen/netfront: don't read data from request on the ring page
+
+From: Juergen Gross <jgross@suse.com>
+
+commit 162081ec33c2686afa29d91bf8d302824aa846c7 upstream.
+
+In order to avoid a malicious backend being able to influence the local
+processing of a request build the request locally first and then copy
+it to the ring page. Any reading from the request influencing the
+processing in the frontend needs to be done on the local instance.
+
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/xen-netfront.c | 80 ++++++++++++++++++++-------------------------
+ 1 file changed, 37 insertions(+), 43 deletions(-)
+
+--- a/drivers/net/xen-netfront.c
++++ b/drivers/net/xen-netfront.c
+@@ -425,7 +425,8 @@ struct xennet_gnttab_make_txreq {
+ struct netfront_queue *queue;
+ struct sk_buff *skb;
+ struct page *page;
+- struct xen_netif_tx_request *tx; /* Last request */
++ struct xen_netif_tx_request *tx; /* Last request on ring page */
++ struct xen_netif_tx_request tx_local; /* Last request local copy*/
+ unsigned int size;
+ };
+
+@@ -453,30 +454,27 @@ static void xennet_tx_setup_grant(unsign
+ queue->grant_tx_page[id] = page;
+ queue->grant_tx_ref[id] = ref;
+
+- tx->id = id;
+- tx->gref = ref;
+- tx->offset = offset;
+- tx->size = len;
+- tx->flags = 0;
++ info->tx_local.id = id;
++ info->tx_local.gref = ref;
++ info->tx_local.offset = offset;
++ info->tx_local.size = len;
++ info->tx_local.flags = 0;
++
++ *tx = info->tx_local;
+
+ info->tx = tx;
+- info->size += tx->size;
++ info->size += info->tx_local.size;
+ }
+
+ static struct xen_netif_tx_request *xennet_make_first_txreq(
+- struct netfront_queue *queue, struct sk_buff *skb,
+- struct page *page, unsigned int offset, unsigned int len)
++ struct xennet_gnttab_make_txreq *info,
++ unsigned int offset, unsigned int len)
+ {
+- struct xennet_gnttab_make_txreq info = {
+- .queue = queue,
+- .skb = skb,
+- .page = page,
+- .size = 0,
+- };
++ info->size = 0;
+
+- gnttab_for_one_grant(page, offset, len, xennet_tx_setup_grant, &info);
++ gnttab_for_one_grant(info->page, offset, len, xennet_tx_setup_grant, info);
+
+- return info.tx;
++ return info->tx;
+ }
+
+ static void xennet_make_one_txreq(unsigned long gfn, unsigned int offset,
+@@ -489,35 +487,27 @@ static void xennet_make_one_txreq(unsign
+ xennet_tx_setup_grant(gfn, offset, len, data);
+ }
+
+-static struct xen_netif_tx_request *xennet_make_txreqs(
+- struct netfront_queue *queue, struct xen_netif_tx_request *tx,
+- struct sk_buff *skb, struct page *page,
++static void xennet_make_txreqs(
++ struct xennet_gnttab_make_txreq *info,
++ struct page *page,
+ unsigned int offset, unsigned int len)
+ {
+- struct xennet_gnttab_make_txreq info = {
+- .queue = queue,
+- .skb = skb,
+- .tx = tx,
+- };
+-
+ /* Skip unused frames from start of page */
+ page += offset >> PAGE_SHIFT;
+ offset &= ~PAGE_MASK;
+
+ while (len) {
+- info.page = page;
+- info.size = 0;
++ info->page = page;
++ info->size = 0;
+
+ gnttab_foreach_grant_in_range(page, offset, len,
+ xennet_make_one_txreq,
+- &info);
++ info);
+
+ page++;
+ offset = 0;
+- len -= info.size;
++ len -= info->size;
+ }
+-
+- return info.tx;
+ }
+
+ /*
+@@ -571,7 +561,7 @@ static netdev_tx_t xennet_start_xmit(str
+ {
+ struct netfront_info *np = netdev_priv(dev);
+ struct netfront_stats *tx_stats = this_cpu_ptr(np->tx_stats);
+- struct xen_netif_tx_request *tx, *first_tx;
++ struct xen_netif_tx_request *first_tx;
+ unsigned int i;
+ int notify;
+ int slots;
+@@ -580,6 +570,7 @@ static netdev_tx_t xennet_start_xmit(str
+ unsigned int len;
+ unsigned long flags;
+ struct netfront_queue *queue = NULL;
++ struct xennet_gnttab_make_txreq info = { };
+ unsigned int num_queues = dev->real_num_tx_queues;
+ u16 queue_index;
+ struct sk_buff *nskb;
+@@ -637,21 +628,24 @@ static netdev_tx_t xennet_start_xmit(str
+ }
+
+ /* First request for the linear area. */
+- first_tx = tx = xennet_make_first_txreq(queue, skb,
+- page, offset, len);
+- offset += tx->size;
++ info.queue = queue;
++ info.skb = skb;
++ info.page = page;
++ first_tx = xennet_make_first_txreq(&info, offset, len);
++ offset += info.tx_local.size;
+ if (offset == PAGE_SIZE) {
+ page++;
+ offset = 0;
+ }
+- len -= tx->size;
++ len -= info.tx_local.size;
+
+ if (skb->ip_summed == CHECKSUM_PARTIAL)
+ /* local packet? */
+- tx->flags |= XEN_NETTXF_csum_blank | XEN_NETTXF_data_validated;
++ first_tx->flags |= XEN_NETTXF_csum_blank |
++ XEN_NETTXF_data_validated;
+ else if (skb->ip_summed == CHECKSUM_UNNECESSARY)
+ /* remote but checksummed. */
+- tx->flags |= XEN_NETTXF_data_validated;
++ first_tx->flags |= XEN_NETTXF_data_validated;
+
+ /* Optional extra info after the first request. */
+ if (skb_shinfo(skb)->gso_size) {
+@@ -660,7 +654,7 @@ static netdev_tx_t xennet_start_xmit(str
+ gso = (struct xen_netif_extra_info *)
+ RING_GET_REQUEST(&queue->tx, queue->tx.req_prod_pvt++);
+
+- tx->flags |= XEN_NETTXF_extra_info;
++ first_tx->flags |= XEN_NETTXF_extra_info;
+
+ gso->u.gso.size = skb_shinfo(skb)->gso_size;
+ gso->u.gso.type = (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) ?
+@@ -674,13 +668,13 @@ static netdev_tx_t xennet_start_xmit(str
+ }
+
+ /* Requests for the rest of the linear area. */
+- tx = xennet_make_txreqs(queue, tx, skb, page, offset, len);
++ xennet_make_txreqs(&info, page, offset, len);
+
+ /* Requests for all the frags. */
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+- tx = xennet_make_txreqs(queue, tx, skb,
+- skb_frag_page(frag), frag->page_offset,
++ xennet_make_txreqs(&info, skb_frag_page(frag),
++ frag->page_offset,
+ skb_frag_size(frag));
+ }
+
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 10:44:30 +0100
+Subject: xen/netfront: don't trust the backend response data blindly
+
+From: Juergen Gross <jgross@suse.com>
+
+commit a884daa61a7d91650987e855464526aef219590f upstream.
+
+Today netfront will trust the backend to send only sane response data.
+In order to avoid privilege escalations or crashes in case of malicious
+backends verify the data to be within expected limits. Especially make
+sure that the response always references an outstanding request.
+
+Note that only the tx queue needs special id handling, as for the rx
+queue the id is equal to the index in the ring page.
+
+Introduce a new indicator for the device whether it is broken and let
+the device stop working when it is set. Set this indicator in case the
+backend sets any weird data.
+
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/xen-netfront.c | 80 ++++++++++++++++++++++++++++++++++++++++++---
+ 1 file changed, 75 insertions(+), 5 deletions(-)
+
+--- a/drivers/net/xen-netfront.c
++++ b/drivers/net/xen-netfront.c
+@@ -126,10 +126,12 @@ struct netfront_queue {
+ struct sk_buff *tx_skbs[NET_TX_RING_SIZE];
+ unsigned short tx_link[NET_TX_RING_SIZE];
+ #define TX_LINK_NONE 0xffff
++#define TX_PENDING 0xfffe
+ grant_ref_t gref_tx_head;
+ grant_ref_t grant_tx_ref[NET_TX_RING_SIZE];
+ struct page *grant_tx_page[NET_TX_RING_SIZE];
+ unsigned tx_skb_freelist;
++ unsigned int tx_pend_queue;
+
+ spinlock_t rx_lock ____cacheline_aligned_in_smp;
+ struct xen_netif_rx_front_ring rx;
+@@ -155,6 +157,9 @@ struct netfront_info {
+ struct netfront_stats __percpu *rx_stats;
+ struct netfront_stats __percpu *tx_stats;
+
++ /* Is device behaving sane? */
++ bool broken;
++
+ atomic_t rx_gso_checksum_fixup;
+ };
+
+@@ -339,7 +344,7 @@ static int xennet_open(struct net_device
+ unsigned int i = 0;
+ struct netfront_queue *queue = NULL;
+
+- if (!np->queues)
++ if (!np->queues || np->broken)
+ return -ENODEV;
+
+ for (i = 0; i < num_queues; ++i) {
+@@ -367,11 +372,17 @@ static void xennet_tx_buf_gc(struct netf
+ unsigned short id;
+ struct sk_buff *skb;
+ bool more_to_do;
++ const struct device *dev = &queue->info->netdev->dev;
+
+ BUG_ON(!netif_carrier_ok(queue->info->netdev));
+
+ do {
+ prod = queue->tx.sring->rsp_prod;
++ if (RING_RESPONSE_PROD_OVERFLOW(&queue->tx, prod)) {
++ dev_alert(dev, "Illegal number of responses %u\n",
++ prod - queue->tx.rsp_cons);
++ goto err;
++ }
+ rmb(); /* Ensure we see responses up to 'rp'. */
+
+ for (cons = queue->tx.rsp_cons; cons != prod; cons++) {
+@@ -381,14 +392,27 @@ static void xennet_tx_buf_gc(struct netf
+ if (txrsp.status == XEN_NETIF_RSP_NULL)
+ continue;
+
+- id = txrsp.id;
++ id = txrsp.id;
++ if (id >= RING_SIZE(&queue->tx)) {
++ dev_alert(dev,
++ "Response has incorrect id (%u)\n",
++ id);
++ goto err;
++ }
++ if (queue->tx_link[id] != TX_PENDING) {
++ dev_alert(dev,
++ "Response for inactive request\n");
++ goto err;
++ }
++
++ queue->tx_link[id] = TX_LINK_NONE;
+ skb = queue->tx_skbs[id];
+ queue->tx_skbs[id] = NULL;
+ if (unlikely(gnttab_query_foreign_access(
+ queue->grant_tx_ref[id]) != 0)) {
+- pr_alert("%s: warning -- grant still in use by backend domain\n",
+- __func__);
+- BUG();
++ dev_alert(dev,
++ "Grant still in use by backend domain\n");
++ goto err;
+ }
+ gnttab_end_foreign_access_ref(
+ queue->grant_tx_ref[id], GNTMAP_readonly);
+@@ -406,6 +430,12 @@ static void xennet_tx_buf_gc(struct netf
+ } while (more_to_do);
+
+ xennet_maybe_wake_tx(queue);
++
++ return;
++
++ err:
++ queue->info->broken = true;
++ dev_alert(dev, "Disabled for further use\n");
+ }
+
+ struct xennet_gnttab_make_txreq {
+@@ -449,6 +479,12 @@ static void xennet_tx_setup_grant(unsign
+
+ *tx = info->tx_local;
+
++ /*
++ * Put the request in the pending queue, it will be set to be pending
++ * when the producer index is about to be raised.
++ */
++ add_id_to_list(&queue->tx_pend_queue, queue->tx_link, id);
++
+ info->tx = tx;
+ info->size += info->tx_local.size;
+ }
+@@ -542,6 +578,15 @@ static u16 xennet_select_queue(struct ne
+ return queue_idx;
+ }
+
++static void xennet_mark_tx_pending(struct netfront_queue *queue)
++{
++ unsigned int i;
++
++ while ((i = get_id_from_list(&queue->tx_pend_queue, queue->tx_link)) !=
++ TX_LINK_NONE)
++ queue->tx_link[i] = TX_PENDING;
++}
++
+ #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1)
+
+ static netdev_tx_t xennet_start_xmit(struct sk_buff *skb, struct net_device *dev)
+@@ -565,6 +610,8 @@ static netdev_tx_t xennet_start_xmit(str
+ /* Drop the packet if no queues are set up */
+ if (num_queues < 1)
+ goto drop;
++ if (unlikely(np->broken))
++ goto drop;
+ /* Determine which queue to transmit this SKB on */
+ queue_index = skb_get_queue_mapping(skb);
+ queue = &np->queues[queue_index];
+@@ -668,6 +715,8 @@ static netdev_tx_t xennet_start_xmit(str
+ /* First request has the packet length. */
+ first_tx->size = skb->len;
+
++ xennet_mark_tx_pending(queue);
++
+ RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->tx, notify);
+ if (notify)
+ notify_remote_via_irq(queue->tx_irq);
+@@ -992,6 +1041,13 @@ static int xennet_poll(struct napi_struc
+ skb_queue_head_init(&tmpq);
+
+ rp = queue->rx.sring->rsp_prod;
++ if (RING_RESPONSE_PROD_OVERFLOW(&queue->rx, rp)) {
++ dev_alert(&dev->dev, "Illegal number of responses %u\n",
++ rp - queue->rx.rsp_cons);
++ queue->info->broken = true;
++ spin_unlock(&queue->rx_lock);
++ return 0;
++ }
+ rmb(); /* Ensure we see queued responses up to 'rp'. */
+
+ i = queue->rx.rsp_cons;
+@@ -1210,6 +1266,9 @@ static irqreturn_t xennet_tx_interrupt(i
+ struct netfront_queue *queue = dev_id;
+ unsigned long flags;
+
++ if (queue->info->broken)
++ return IRQ_HANDLED;
++
+ spin_lock_irqsave(&queue->tx_lock, flags);
+ xennet_tx_buf_gc(queue);
+ spin_unlock_irqrestore(&queue->tx_lock, flags);
+@@ -1222,6 +1281,9 @@ static irqreturn_t xennet_rx_interrupt(i
+ struct netfront_queue *queue = dev_id;
+ struct net_device *dev = queue->info->netdev;
+
++ if (queue->info->broken)
++ return IRQ_HANDLED;
++
+ if (likely(netif_carrier_ok(dev) &&
+ RING_HAS_UNCONSUMED_RESPONSES(&queue->rx)))
+ napi_schedule(&queue->napi);
+@@ -1243,6 +1305,10 @@ static void xennet_poll_controller(struc
+ struct netfront_info *info = netdev_priv(dev);
+ unsigned int num_queues = dev->real_num_tx_queues;
+ unsigned int i;
++
++ if (info->broken)
++ return;
++
+ for (i = 0; i < num_queues; ++i)
+ xennet_interrupt(0, &info->queues[i]);
+ }
+@@ -1614,6 +1680,7 @@ static int xennet_init_queue(struct netf
+
+ /* Initialise tx_skb_freelist as a free chain containing every entry. */
+ queue->tx_skb_freelist = 0;
++ queue->tx_pend_queue = TX_LINK_NONE;
+ for (i = 0; i < NET_TX_RING_SIZE; i++) {
+ queue->tx_link[i] = i + 1;
+ queue->grant_tx_ref[i] = GRANT_INVALID_REF;
+@@ -1824,6 +1891,9 @@ static int talk_to_netback(struct xenbus
+ if (info->queues)
+ xennet_destroy_queues(info);
+
++ /* For the case of a reconnect reset the "broken" indicator. */
++ info->broken = false;
++
+ err = xennet_create_queues(info, &num_queues);
+ if (err < 0) {
+ xenbus_dev_fatal(dev, err, "creating queues");
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 08:58:22 +0100
+Subject: xen/netfront: read response from backend only once
+
+From: Juergen Gross <jgross@suse.com>
+
+commit 8446066bf8c1f9f7b7412c43fbea0fb87464d75b upstream.
+
+In order to avoid problems in case the backend is modifying a response
+on the ring page while the frontend has already seen it, just read the
+response into a local buffer in one go and then operate on that buffer
+only.
+
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/xen-netfront.c | 38 +++++++++++++++++++-------------------
+ 1 file changed, 19 insertions(+), 19 deletions(-)
+
+--- a/drivers/net/xen-netfront.c
++++ b/drivers/net/xen-netfront.c
+@@ -389,13 +389,13 @@ static void xennet_tx_buf_gc(struct netf
+ rmb(); /* Ensure we see responses up to 'rp'. */
+
+ for (cons = queue->tx.rsp_cons; cons != prod; cons++) {
+- struct xen_netif_tx_response *txrsp;
++ struct xen_netif_tx_response txrsp;
+
+- txrsp = RING_GET_RESPONSE(&queue->tx, cons);
+- if (txrsp->status == XEN_NETIF_RSP_NULL)
++ RING_COPY_RESPONSE(&queue->tx, cons, &txrsp);
++ if (txrsp.status == XEN_NETIF_RSP_NULL)
+ continue;
+
+- id = txrsp->id;
++ id = txrsp.id;
+ skb = queue->tx_skbs[id].skb;
+ if (unlikely(gnttab_query_foreign_access(
+ queue->grant_tx_ref[id]) != 0)) {
+@@ -744,7 +744,7 @@ static int xennet_get_extras(struct netf
+ RING_IDX rp)
+
+ {
+- struct xen_netif_extra_info *extra;
++ struct xen_netif_extra_info extra;
+ struct device *dev = &queue->info->netdev->dev;
+ RING_IDX cons = queue->rx.rsp_cons;
+ int err = 0;
+@@ -760,24 +760,22 @@ static int xennet_get_extras(struct netf
+ break;
+ }
+
+- extra = (struct xen_netif_extra_info *)
+- RING_GET_RESPONSE(&queue->rx, ++cons);
++ RING_COPY_RESPONSE(&queue->rx, ++cons, &extra);
+
+- if (unlikely(!extra->type ||
+- extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
++ if (unlikely(!extra.type ||
++ extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
+ if (net_ratelimit())
+ dev_warn(dev, "Invalid extra type: %d\n",
+- extra->type);
++ extra.type);
+ err = -EINVAL;
+ } else {
+- memcpy(&extras[extra->type - 1], extra,
+- sizeof(*extra));
++ extras[extra.type - 1] = extra;
+ }
+
+ skb = xennet_get_rx_skb(queue, cons);
+ ref = xennet_get_rx_ref(queue, cons);
+ xennet_move_rx_slot(queue, skb, ref);
+- } while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE);
++ } while (extra.flags & XEN_NETIF_EXTRA_FLAG_MORE);
+
+ queue->rx.rsp_cons = cons;
+ return err;
+@@ -787,7 +785,7 @@ static int xennet_get_responses(struct n
+ struct netfront_rx_info *rinfo, RING_IDX rp,
+ struct sk_buff_head *list)
+ {
+- struct xen_netif_rx_response *rx = &rinfo->rx;
++ struct xen_netif_rx_response *rx = &rinfo->rx, rx_local;
+ struct xen_netif_extra_info *extras = rinfo->extras;
+ struct device *dev = &queue->info->netdev->dev;
+ RING_IDX cons = queue->rx.rsp_cons;
+@@ -845,7 +843,8 @@ next:
+ break;
+ }
+
+- rx = RING_GET_RESPONSE(&queue->rx, cons + slots);
++ RING_COPY_RESPONSE(&queue->rx, cons + slots, &rx_local);
++ rx = &rx_local;
+ skb = xennet_get_rx_skb(queue, cons + slots);
+ ref = xennet_get_rx_ref(queue, cons + slots);
+ slots++;
+@@ -900,10 +899,11 @@ static int xennet_fill_frags(struct netf
+ struct sk_buff *nskb;
+
+ while ((nskb = __skb_dequeue(list))) {
+- struct xen_netif_rx_response *rx =
+- RING_GET_RESPONSE(&queue->rx, ++cons);
++ struct xen_netif_rx_response rx;
+ skb_frag_t *nfrag = &skb_shinfo(nskb)->frags[0];
+
++ RING_COPY_RESPONSE(&queue->rx, ++cons, &rx);
++
+ if (skb_shinfo(skb)->nr_frags == MAX_SKB_FRAGS) {
+ unsigned int pull_to = NETFRONT_SKB_CB(skb)->pull_to;
+
+@@ -918,7 +918,7 @@ static int xennet_fill_frags(struct netf
+
+ skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
+ skb_frag_page(nfrag),
+- rx->offset, rx->status, PAGE_SIZE);
++ rx.offset, rx.status, PAGE_SIZE);
+
+ skb_shinfo(nskb)->nr_frags = 0;
+ kfree_skb(nskb);
+@@ -1016,7 +1016,7 @@ static int xennet_poll(struct napi_struc
+ i = queue->rx.rsp_cons;
+ work_done = 0;
+ while ((i != rp) && (work_done < budget)) {
+- memcpy(rx, RING_GET_RESPONSE(&queue->rx, i), sizeof(*rx));
++ RING_COPY_RESPONSE(&queue->rx, i, rx);
+ memset(extras, 0, sizeof(rinfo.extras));
+
+ err = xennet_get_responses(queue, &rinfo, rp, &tmpq);
--- /dev/null
+From foo@baz Mon Nov 29 06:50:25 PM CET 2021
+From: Juergen Gross <jgross@suse.com>
+Date: Mon, 29 Nov 2021 08:36:21 +0100
+Subject: xen: sync include/xen/interface/io/ring.h with Xen's newest version
+
+From: Juergen Gross <jgross@suse.com>
+
+commit 629a5d87e26fe96bcaab44cbb81f5866af6f7008 upstream.
+
+Sync include/xen/interface/io/ring.h with Xen's newest version in
+order to get the RING_COPY_RESPONSE() and RING_RESPONSE_PROD_OVERFLOW()
+macros.
+
+Note that this will correct the wrong license info by adding the
+missing original copyright notice.
+
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/xen/interface/io/ring.h | 307 +++++++++++++++++++++-------------------
+ 1 file changed, 165 insertions(+), 142 deletions(-)
+
+--- a/include/xen/interface/io/ring.h
++++ b/include/xen/interface/io/ring.h
+@@ -1,21 +1,53 @@
+-/* SPDX-License-Identifier: GPL-2.0 */
+ /******************************************************************************
+ * ring.h
+ *
+ * Shared producer-consumer ring macros.
+ *
++ * Permission is hereby granted, free of charge, to any person obtaining a copy
++ * of this software and associated documentation files (the "Software"), to
++ * deal in the Software without restriction, including without limitation the
++ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
++ * sell copies of the Software, and to permit persons to whom the Software is
++ * furnished to do so, subject to the following conditions:
++ *
++ * The above copyright notice and this permission notice shall be included in
++ * all copies or substantial portions of the Software.
++ *
++ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
++ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
++ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
++ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
++ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
++ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
++ * DEALINGS IN THE SOFTWARE.
++ *
+ * Tim Deegan and Andrew Warfield November 2004.
+ */
+
+ #ifndef __XEN_PUBLIC_IO_RING_H__
+ #define __XEN_PUBLIC_IO_RING_H__
+
++/*
++ * When #include'ing this header, you need to provide the following
++ * declaration upfront:
++ * - standard integers types (uint8_t, uint16_t, etc)
++ * They are provided by stdint.h of the standard headers.
++ *
++ * In addition, if you intend to use the FLEX macros, you also need to
++ * provide the following, before invoking the FLEX macros:
++ * - size_t
++ * - memcpy
++ * - grant_ref_t
++ * These declarations are provided by string.h of the standard headers,
++ * and grant_table.h from the Xen public headers.
++ */
++
+ #include <xen/interface/grant_table.h>
+
+ typedef unsigned int RING_IDX;
+
+ /* Round a 32-bit unsigned constant down to the nearest power of two. */
+-#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
++#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
+ #define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
+ #define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
+ #define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
+@@ -27,82 +59,79 @@ typedef unsigned int RING_IDX;
+ * A ring contains as many entries as will fit, rounded down to the nearest
+ * power of two (so we can mask with (size-1) to loop around).
+ */
+-#define __CONST_RING_SIZE(_s, _sz) \
+- (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
+- sizeof(((struct _s##_sring *)0)->ring[0])))
+-
++#define __CONST_RING_SIZE(_s, _sz) \
++ (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
++ sizeof(((struct _s##_sring *)0)->ring[0])))
+ /*
+ * The same for passing in an actual pointer instead of a name tag.
+ */
+-#define __RING_SIZE(_s, _sz) \
+- (__RD32(((_sz) - (long)&(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
++#define __RING_SIZE(_s, _sz) \
++ (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
+
+ /*
+ * Macros to make the correct C datatypes for a new kind of ring.
+ *
+ * To make a new ring datatype, you need to have two message structures,
+- * let's say struct request, and struct response already defined.
++ * let's say request_t, and response_t already defined.
+ *
+ * In a header where you want the ring datatype declared, you then do:
+ *
+- * DEFINE_RING_TYPES(mytag, struct request, struct response);
++ * DEFINE_RING_TYPES(mytag, request_t, response_t);
+ *
+ * These expand out to give you a set of types, as you can see below.
+ * The most important of these are:
+ *
+- * struct mytag_sring - The shared ring.
+- * struct mytag_front_ring - The 'front' half of the ring.
+- * struct mytag_back_ring - The 'back' half of the ring.
++ * mytag_sring_t - The shared ring.
++ * mytag_front_ring_t - The 'front' half of the ring.
++ * mytag_back_ring_t - The 'back' half of the ring.
+ *
+ * To initialize a ring in your code you need to know the location and size
+ * of the shared memory area (PAGE_SIZE, for instance). To initialise
+ * the front half:
+ *
+- * struct mytag_front_ring front_ring;
+- * SHARED_RING_INIT((struct mytag_sring *)shared_page);
+- * FRONT_RING_INIT(&front_ring, (struct mytag_sring *)shared_page,
+- * PAGE_SIZE);
++ * mytag_front_ring_t front_ring;
++ * SHARED_RING_INIT((mytag_sring_t *)shared_page);
++ * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ *
+ * Initializing the back follows similarly (note that only the front
+ * initializes the shared ring):
+ *
+- * struct mytag_back_ring back_ring;
+- * BACK_RING_INIT(&back_ring, (struct mytag_sring *)shared_page,
+- * PAGE_SIZE);
++ * mytag_back_ring_t back_ring;
++ * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ */
+
+-#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
+- \
+-/* Shared ring entry */ \
+-union __name##_sring_entry { \
+- __req_t req; \
+- __rsp_t rsp; \
+-}; \
+- \
+-/* Shared ring page */ \
+-struct __name##_sring { \
+- RING_IDX req_prod, req_event; \
+- RING_IDX rsp_prod, rsp_event; \
+- uint8_t pad[48]; \
+- union __name##_sring_entry ring[1]; /* variable-length */ \
+-}; \
+- \
+-/* "Front" end's private variables */ \
+-struct __name##_front_ring { \
+- RING_IDX req_prod_pvt; \
+- RING_IDX rsp_cons; \
+- unsigned int nr_ents; \
+- struct __name##_sring *sring; \
+-}; \
+- \
+-/* "Back" end's private variables */ \
+-struct __name##_back_ring { \
+- RING_IDX rsp_prod_pvt; \
+- RING_IDX req_cons; \
+- unsigned int nr_ents; \
+- struct __name##_sring *sring; \
+-};
+-
++#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
++ \
++/* Shared ring entry */ \
++union __name##_sring_entry { \
++ __req_t req; \
++ __rsp_t rsp; \
++}; \
++ \
++/* Shared ring page */ \
++struct __name##_sring { \
++ RING_IDX req_prod, req_event; \
++ RING_IDX rsp_prod, rsp_event; \
++ uint8_t __pad[48]; \
++ union __name##_sring_entry ring[1]; /* variable-length */ \
++}; \
++ \
++/* "Front" end's private variables */ \
++struct __name##_front_ring { \
++ RING_IDX req_prod_pvt; \
++ RING_IDX rsp_cons; \
++ unsigned int nr_ents; \
++ struct __name##_sring *sring; \
++}; \
++ \
++/* "Back" end's private variables */ \
++struct __name##_back_ring { \
++ RING_IDX rsp_prod_pvt; \
++ RING_IDX req_cons; \
++ unsigned int nr_ents; \
++ struct __name##_sring *sring; \
++}; \
++ \
+ /*
+ * Macros for manipulating rings.
+ *
+@@ -119,105 +148,99 @@ struct __name##_back_ring { \
+ */
+
+ /* Initialising empty rings */
+-#define SHARED_RING_INIT(_s) do { \
+- (_s)->req_prod = (_s)->rsp_prod = 0; \
+- (_s)->req_event = (_s)->rsp_event = 1; \
+- memset((_s)->pad, 0, sizeof((_s)->pad)); \
++#define SHARED_RING_INIT(_s) do { \
++ (_s)->req_prod = (_s)->rsp_prod = 0; \
++ (_s)->req_event = (_s)->rsp_event = 1; \
++ (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
+ } while(0)
+
+-#define FRONT_RING_INIT(_r, _s, __size) do { \
+- (_r)->req_prod_pvt = 0; \
+- (_r)->rsp_cons = 0; \
+- (_r)->nr_ents = __RING_SIZE(_s, __size); \
+- (_r)->sring = (_s); \
++#define FRONT_RING_ATTACH(_r, _s, _i, __size) do { \
++ (_r)->req_prod_pvt = (_i); \
++ (_r)->rsp_cons = (_i); \
++ (_r)->nr_ents = __RING_SIZE(_s, __size); \
++ (_r)->sring = (_s); \
+ } while (0)
+
+-#define BACK_RING_INIT(_r, _s, __size) do { \
+- (_r)->rsp_prod_pvt = 0; \
+- (_r)->req_cons = 0; \
+- (_r)->nr_ents = __RING_SIZE(_s, __size); \
+- (_r)->sring = (_s); \
+-} while (0)
++#define FRONT_RING_INIT(_r, _s, __size) FRONT_RING_ATTACH(_r, _s, 0, __size)
+
+-/* Initialize to existing shared indexes -- for recovery */
+-#define FRONT_RING_ATTACH(_r, _s, __size) do { \
+- (_r)->sring = (_s); \
+- (_r)->req_prod_pvt = (_s)->req_prod; \
+- (_r)->rsp_cons = (_s)->rsp_prod; \
+- (_r)->nr_ents = __RING_SIZE(_s, __size); \
++#define BACK_RING_ATTACH(_r, _s, _i, __size) do { \
++ (_r)->rsp_prod_pvt = (_i); \
++ (_r)->req_cons = (_i); \
++ (_r)->nr_ents = __RING_SIZE(_s, __size); \
++ (_r)->sring = (_s); \
+ } while (0)
+
+-#define BACK_RING_ATTACH(_r, _s, __size) do { \
+- (_r)->sring = (_s); \
+- (_r)->rsp_prod_pvt = (_s)->rsp_prod; \
+- (_r)->req_cons = (_s)->req_prod; \
+- (_r)->nr_ents = __RING_SIZE(_s, __size); \
+-} while (0)
++#define BACK_RING_INIT(_r, _s, __size) BACK_RING_ATTACH(_r, _s, 0, __size)
+
+ /* How big is this ring? */
+-#define RING_SIZE(_r) \
++#define RING_SIZE(_r) \
+ ((_r)->nr_ents)
+
+ /* Number of free requests (for use on front side only). */
+-#define RING_FREE_REQUESTS(_r) \
++#define RING_FREE_REQUESTS(_r) \
+ (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
+
+ /* Test if there is an empty slot available on the front ring.
+ * (This is only meaningful from the front. )
+ */
+-#define RING_FULL(_r) \
++#define RING_FULL(_r) \
+ (RING_FREE_REQUESTS(_r) == 0)
+
+ /* Test if there are outstanding messages to be processed on a ring. */
+-#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
++#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
+ ((_r)->sring->rsp_prod - (_r)->rsp_cons)
+
+-#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
+- ({ \
+- unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
+- unsigned int rsp = RING_SIZE(_r) - \
+- ((_r)->req_cons - (_r)->rsp_prod_pvt); \
+- req < rsp ? req : rsp; \
+- })
++#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
++ unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
++ unsigned int rsp = RING_SIZE(_r) - \
++ ((_r)->req_cons - (_r)->rsp_prod_pvt); \
++ req < rsp ? req : rsp; \
++})
+
+ /* Direct access to individual ring elements, by index. */
+-#define RING_GET_REQUEST(_r, _idx) \
++#define RING_GET_REQUEST(_r, _idx) \
+ (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
+
++#define RING_GET_RESPONSE(_r, _idx) \
++ (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
++
+ /*
+- * Get a local copy of a request.
++ * Get a local copy of a request/response.
+ *
+- * Use this in preference to RING_GET_REQUEST() so all processing is
++ * Use this in preference to RING_GET_{REQUEST,RESPONSE}() so all processing is
+ * done on a local copy that cannot be modified by the other end.
+ *
+ * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
+- * to be ineffective where _req is a struct which consists of only bitfields.
++ * to be ineffective where dest is a struct which consists of only bitfields.
+ */
+-#define RING_COPY_REQUEST(_r, _idx, _req) do { \
+- /* Use volatile to force the copy into _req. */ \
+- *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
++#define RING_COPY_(type, r, idx, dest) do { \
++ /* Use volatile to force the copy into dest. */ \
++ *(dest) = *(volatile typeof(dest))RING_GET_##type(r, idx); \
+ } while (0)
+
+-#define RING_GET_RESPONSE(_r, _idx) \
+- (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
++#define RING_COPY_REQUEST(r, idx, req) RING_COPY_(REQUEST, r, idx, req)
++#define RING_COPY_RESPONSE(r, idx, rsp) RING_COPY_(RESPONSE, r, idx, rsp)
+
+ /* Loop termination condition: Would the specified index overflow the ring? */
+-#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
++#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
+ (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
+
+ /* Ill-behaved frontend determination: Can there be this many requests? */
+-#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
++#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
+ (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
+
+-
+-#define RING_PUSH_REQUESTS(_r) do { \
+- virt_wmb(); /* back sees requests /before/ updated producer index */ \
+- (_r)->sring->req_prod = (_r)->req_prod_pvt; \
++/* Ill-behaved backend determination: Can there be this many responses? */
++#define RING_RESPONSE_PROD_OVERFLOW(_r, _prod) \
++ (((_prod) - (_r)->rsp_cons) > RING_SIZE(_r))
++
++#define RING_PUSH_REQUESTS(_r) do { \
++ virt_wmb(); /* back sees requests /before/ updated producer index */\
++ (_r)->sring->req_prod = (_r)->req_prod_pvt; \
+ } while (0)
+
+-#define RING_PUSH_RESPONSES(_r) do { \
+- virt_wmb(); /* front sees responses /before/ updated producer index */ \
+- (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
++#define RING_PUSH_RESPONSES(_r) do { \
++ virt_wmb(); /* front sees resps /before/ updated producer index */ \
++ (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
+ } while (0)
+
+ /*
+@@ -250,40 +273,40 @@ struct __name##_back_ring { \
+ * field appropriately.
+ */
+
+-#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
+- RING_IDX __old = (_r)->sring->req_prod; \
+- RING_IDX __new = (_r)->req_prod_pvt; \
+- virt_wmb(); /* back sees requests /before/ updated producer index */ \
+- (_r)->sring->req_prod = __new; \
+- virt_mb(); /* back sees new requests /before/ we check req_event */ \
+- (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
+- (RING_IDX)(__new - __old)); \
+-} while (0)
+-
+-#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
+- RING_IDX __old = (_r)->sring->rsp_prod; \
+- RING_IDX __new = (_r)->rsp_prod_pvt; \
+- virt_wmb(); /* front sees responses /before/ updated producer index */ \
+- (_r)->sring->rsp_prod = __new; \
+- virt_mb(); /* front sees new responses /before/ we check rsp_event */ \
+- (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
+- (RING_IDX)(__new - __old)); \
+-} while (0)
+-
+-#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
+- (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
+- if (_work_to_do) break; \
+- (_r)->sring->req_event = (_r)->req_cons + 1; \
+- virt_mb(); \
+- (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
+-} while (0)
+-
+-#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
+- (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
+- if (_work_to_do) break; \
+- (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
+- virt_mb(); \
+- (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
++#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
++ RING_IDX __old = (_r)->sring->req_prod; \
++ RING_IDX __new = (_r)->req_prod_pvt; \
++ virt_wmb(); /* back sees requests /before/ updated producer index */\
++ (_r)->sring->req_prod = __new; \
++ virt_mb(); /* back sees new requests /before/ we check req_event */ \
++ (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
++ (RING_IDX)(__new - __old)); \
++} while (0)
++
++#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
++ RING_IDX __old = (_r)->sring->rsp_prod; \
++ RING_IDX __new = (_r)->rsp_prod_pvt; \
++ virt_wmb(); /* front sees resps /before/ updated producer index */ \
++ (_r)->sring->rsp_prod = __new; \
++ virt_mb(); /* front sees new resps /before/ we check rsp_event */ \
++ (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
++ (RING_IDX)(__new - __old)); \
++} while (0)
++
++#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
++ (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
++ if (_work_to_do) break; \
++ (_r)->sring->req_event = (_r)->req_cons + 1; \
++ virt_mb(); \
++ (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
++} while (0)
++
++#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
++ (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
++ if (_work_to_do) break; \
++ (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
++ virt_mb(); \
++ (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
+ } while (0)
+
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
