Merge tag 'rds-odp-for-5.5' into rdma.git for-next

From https://git.kernel.org/pub/scm/linux/kernel/git/leon/linux-rdma

Leon Romanovsky says:

====================
Use ODP MRs for kernel ULPs

The following series extends MR creation routines to allow creation of
user MRs through kernel ULPs as a proxy. The immediate use case is to
allow RDS to work over FS-DAX, which requires ODP (on-demand-paging)
MRs to be created and such MRs were not possible to create prior this
series.

The first part of this patchset extends RDMA to have special verb
ib_reg_user_mr(). The common use case that uses this function is a
userspace application that allocates memory for HCA access but the
responsibility to register the memory at the HCA is on an kernel ULP.
This ULP acts as an agent for the userspace application.

The second part provides advise MR functionality for ULPs. This is
integral part of ODP flows and used to trigger pagefaults in advance
to prepare memory before running working set.

The third part is actual user of those in-kernel APIs.
====================

* tag 'rds-odp-for-5.5':
  net/rds: Use prefetch for On-Demand-Paging MR
  net/rds: Handle ODP mr registration/unregistration
  net/rds: Detect need of On-Demand-Paging memory registration
  RDMA/mlx5: Fix handling of IOVA != user_va in ODP paths
  IB/mlx5: Mask out unsupported ODP capabilities for kernel QPs
  RDMA/mlx5: Don't fake udata for kernel path
  IB/mlx5: Add ODP WQE handlers for kernel QPs
  IB/core: Add interface to advise_mr for kernel users
  IB/core: Introduce ib_reg_user_mr
  IB: Allow calls to ib_umem_get from kernel ULPs

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 66 insertions, 16 deletions

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 5f40117e68e7..26bc05e48d8a 100644
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -203,9 +203,58 @@ static const unsigned short super_speed_maxpacket_maxes[4] = {
 	[USB_ENDPOINT_XFER_INT] = 1024,
 };
 
-static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
-    int asnum, struct usb_host_interface *ifp, int num_ep,
-    unsigned char *buffer, int size)
+static bool endpoint_is_duplicate(struct usb_endpoint_descriptor *e1,
+		struct usb_endpoint_descriptor *e2)
+{
+	if (e1->bEndpointAddress == e2->bEndpointAddress)
+		return true;
+
+	if (usb_endpoint_xfer_control(e1) || usb_endpoint_xfer_control(e2)) {
+		if (usb_endpoint_num(e1) == usb_endpoint_num(e2))
+			return true;
+	}
+
+	return false;
+}
+
+/*
+ * Check for duplicate endpoint addresses in other interfaces and in the
+ * altsetting currently being parsed.
+ */
+static bool config_endpoint_is_duplicate(struct usb_host_config *config,
+		int inum, int asnum, struct usb_endpoint_descriptor *d)
+{
+	struct usb_endpoint_descriptor *epd;
+	struct usb_interface_cache *intfc;
+	struct usb_host_interface *alt;
+	int i, j, k;
+
+	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
+		intfc = config->intf_cache[i];
+
+		for (j = 0; j < intfc->num_altsetting; ++j) {
+			alt = &intfc->altsetting[j];
+
+			if (alt->desc.bInterfaceNumber == inum &&
+					alt->desc.bAlternateSetting != asnum)
+				continue;
+
+			for (k = 0; k < alt->desc.bNumEndpoints; ++k) {
+				epd = &alt->endpoint[k].desc;
+
+				if (endpoint_is_duplicate(epd, d))
+					return true;
+			}
+		}
+	}
+
+	return false;
+}
+
+static int usb_parse_endpoint(struct device *ddev, int cfgno,
+		struct usb_host_config *config, int inum, int asnum,
+		struct usb_host_interface *ifp, int num_ep,
+		unsigned char *buffer, int size)
 {
 	unsigned char *buffer0 = buffer;
 	struct usb_endpoint_descriptor *d;
@@ -242,13 +291,10 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
 		goto skip_to_next_endpoint_or_interface_descriptor;
 
 	/* Check for duplicate endpoint addresses */
-	for (i = 0; i < ifp->desc.bNumEndpoints; ++i) {
-		if (ifp->endpoint[i].desc.bEndpointAddress ==
-		    d->bEndpointAddress) {
-			dev_warn(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n",
-			    cfgno, inum, asnum, d->bEndpointAddress);
-			goto skip_to_next_endpoint_or_interface_descriptor;
-		}
+	if (config_endpoint_is_duplicate(config, inum, asnum, d)) {
+		dev_warn(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n",
+				cfgno, inum, asnum, d->bEndpointAddress);
+		goto skip_to_next_endpoint_or_interface_descriptor;
 	}
 
 	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
@@ -346,12 +392,16 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
 			endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
 	}
 
-	/* Validate the wMaxPacketSize field */
+	/*
+	 * Validate the wMaxPacketSize field.
+	 * Some devices have isochronous endpoints in altsetting 0;
+	 * the USB-2 spec requires such endpoints to have wMaxPacketSize = 0
+	 * (see the end of section 5.6.3), so don't warn about them.
+	 */
 	maxp = usb_endpoint_maxp(&endpoint->desc);
-	if (maxp == 0) {
-		dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has wMaxPacketSize 0, skipping\n",
+	if (maxp == 0 && !(usb_endpoint_xfer_isoc(d) && asnum == 0)) {
+		dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid wMaxPacketSize 0\n",
 		    cfgno, inum, asnum, d->bEndpointAddress);
-		goto skip_to_next_endpoint_or_interface_descriptor;
 	}
 
 	/* Find the highest legal maxpacket size for this endpoint */
@@ -522,8 +572,8 @@ static int usb_parse_interface(struct device *ddev, int cfgno,
 		if (((struct usb_descriptor_header *) buffer)->bDescriptorType
 		     == USB_DT_INTERFACE)
 			break;
-		retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
-		    num_ep, buffer, size);
+		retval = usb_parse_endpoint(ddev, cfgno, config, inum, asnum,
+				alt, num_ep, buffer, size);
 		if (retval < 0)
 			return retval;
 		++n;