All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jason Gunthorpe <jgg@nvidia.com>
To: unlisted-recipients:; (no To-header on input)
Cc: Alex Williamson <alex.williamson@redhat.com>,
	Lu Baolu <baolu.lu@linux.intel.com>,
	Chaitanya Kulkarni <chaitanyak@nvidia.com>,
	Cornelia Huck <cohuck@redhat.com>,
	Daniel Jordan <daniel.m.jordan@oracle.com>,
	David Gibson <david@gibson.dropbear.id.au>,
	Eric Auger <eric.auger@redhat.com>,
	Eric Farman <farman@linux.ibm.com>,
	iommu@lists.linux.dev, Jason Wang <jasowang@redhat.com>,
	Jean-Philippe Brucker <jean-philippe@linaro.org>,
	Joao Martins <joao.m.martins@oracle.com>,
	Kevin Tian <kevin.tian@intel.com>,
	kvm@vger.kernel.org, Matthew Rosato <mjrosato@linux.ibm.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Nicolin Chen <nicolinc@nvidia.com>,
	Niklas Schnelle <schnelle@linux.ibm.com>,
	Shameerali Kolothum Thodi  <shameerali.kolothum.thodi@huawei.com>,
	Yi Liu <yi.l.liu@intel.com>, Keqian Zhu <zhukeqian1@huawei.com>
Subject: [PATCH RFC v2 08/13] iommufd: IOCTLs for the io_pagetable
Date: Fri,  2 Sep 2022 16:59:24 -0300	[thread overview]
Message-ID: <8-v2-f9436d0bde78+4bb-iommufd_jgg@nvidia.com> (raw)
In-Reply-To: <0-v2-f9436d0bde78+4bb-iommufd_jgg@nvidia.com>

Connect the IOAS to its IOCTL interface. This exposes most of the
functionality in the io_pagetable to userspace.

This is intended to be the core of the generic interface that IOMMUFD will
provide. Every IOMMU driver should be able to implement an iommu_domain
that is compatible with this generic mechanism.

It is also designed to be easy to use for simple non virtual machine
monitor users, like DPDK:
 - Universal simple support for all IOMMUs (no PPC special path)
 - An IOVA allocator that considers the aperture and the allowed/reserved
   ranges
 - io_pagetable allows any number of iommu_domains to be connected to the
   IOAS

Along with room in the design to add non-generic features to cater to
specific HW functionality.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
 drivers/iommu/iommufd/Makefile          |   1 +
 drivers/iommu/iommufd/ioas.c            | 316 ++++++++++++++++++++++++
 drivers/iommu/iommufd/iommufd_private.h |  28 +++
 drivers/iommu/iommufd/main.c            |  20 ++
 include/uapi/linux/iommufd.h            | 188 ++++++++++++++
 5 files changed, 553 insertions(+)
 create mode 100644 drivers/iommu/iommufd/ioas.c

diff --git a/drivers/iommu/iommufd/Makefile b/drivers/iommu/iommufd/Makefile
index b66a8c47ff55ec..2b4f36f1b72f9d 100644
--- a/drivers/iommu/iommufd/Makefile
+++ b/drivers/iommu/iommufd/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 iommufd-y := \
 	io_pagetable.o \
+	ioas.o \
 	main.o \
 	pages.o
 
diff --git a/drivers/iommu/iommufd/ioas.c b/drivers/iommu/iommufd/ioas.c
new file mode 100644
index 00000000000000..f9f545158a4891
--- /dev/null
+++ b/drivers/iommu/iommufd/ioas.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES
+ */
+#include <linux/interval_tree.h>
+#include <linux/iommufd.h>
+#include <linux/iommu.h>
+#include <uapi/linux/iommufd.h>
+
+#include "io_pagetable.h"
+
+void iommufd_ioas_destroy(struct iommufd_object *obj)
+{
+	struct iommufd_ioas *ioas = container_of(obj, struct iommufd_ioas, obj);
+	int rc;
+
+	rc = iopt_unmap_all(&ioas->iopt, NULL);
+	WARN_ON(rc && rc != -ENOENT);
+	iopt_destroy_table(&ioas->iopt);
+}
+
+struct iommufd_ioas *iommufd_ioas_alloc(struct iommufd_ctx *ictx)
+{
+	struct iommufd_ioas *ioas;
+	int rc;
+
+	ioas = iommufd_object_alloc(ictx, ioas, IOMMUFD_OBJ_IOAS);
+	if (IS_ERR(ioas))
+		return ioas;
+
+	rc = iopt_init_table(&ioas->iopt);
+	if (rc)
+		goto out_abort;
+	return ioas;
+
+out_abort:
+	iommufd_object_abort(ictx, &ioas->obj);
+	return ERR_PTR(rc);
+}
+
+int iommufd_ioas_alloc_ioctl(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_alloc *cmd = ucmd->cmd;
+	struct iommufd_ioas *ioas;
+	int rc;
+
+	if (cmd->flags)
+		return -EOPNOTSUPP;
+
+	ioas = iommufd_ioas_alloc(ucmd->ictx);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	cmd->out_ioas_id = ioas->obj.id;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+	if (rc)
+		goto out_table;
+	iommufd_object_finalize(ucmd->ictx, &ioas->obj);
+	return 0;
+
+out_table:
+	iommufd_ioas_destroy(&ioas->obj);
+	return rc;
+}
+
+int iommufd_ioas_iova_ranges(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_iova_ranges __user *uptr = ucmd->ubuffer;
+	struct iommu_ioas_iova_ranges *cmd = ucmd->cmd;
+	struct iommufd_ioas *ioas;
+	struct interval_tree_span_iter span;
+	u32 max_iovas;
+	int rc;
+
+	if (cmd->__reserved)
+		return -EOPNOTSUPP;
+
+	max_iovas = cmd->size - sizeof(*cmd);
+	if (max_iovas % sizeof(cmd->out_valid_iovas[0]))
+		return -EINVAL;
+	max_iovas /= sizeof(cmd->out_valid_iovas[0]);
+
+	ioas = iommufd_get_ioas(ucmd, cmd->ioas_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	down_read(&ioas->iopt.iova_rwsem);
+	cmd->out_num_iovas = 0;
+	interval_tree_for_each_span (&span, &ioas->iopt.reserved_itree,
+				     0, ULONG_MAX) {
+		if (!span.is_hole)
+			continue;
+		if (cmd->out_num_iovas < max_iovas) {
+			rc = put_user((u64)span.start_hole,
+				      &uptr->out_valid_iovas[cmd->out_num_iovas]
+					       .start);
+			if (rc)
+				goto out_put;
+			rc = put_user(
+				(u64)span.last_hole,
+				&uptr->out_valid_iovas[cmd->out_num_iovas].last);
+			if (rc)
+				goto out_put;
+		}
+		cmd->out_num_iovas++;
+	}
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+	if (rc)
+		goto out_put;
+	if (cmd->out_num_iovas > max_iovas)
+		rc = -EMSGSIZE;
+out_put:
+	up_read(&ioas->iopt.iova_rwsem);
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
+
+static int iommufd_ioas_load_iovas(struct rb_root_cached *itree,
+				   struct iommu_iova_range __user *ranges,
+				   u32 num)
+{
+	u32 i;
+
+	for (i = 0; i != num; i++) {
+		struct iommu_iova_range range;
+		struct iopt_allowed *allowed;
+
+		if (copy_from_user(&range, ranges + i, sizeof(range)))
+			return -EFAULT;
+
+		if (range.start >= range.last)
+			return -EINVAL;
+
+		if (interval_tree_iter_first(itree, range.start, range.last))
+			return -EINVAL;
+
+		allowed = kzalloc(sizeof(*allowed), GFP_KERNEL_ACCOUNT);
+		if (!allowed)
+			return -ENOMEM;
+		allowed->node.start = range.start;
+		allowed->node.last = range.last;
+
+		interval_tree_insert(&allowed->node, itree);
+	}
+	return 0;
+}
+
+int iommufd_ioas_allow_iovas(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_allow_iovas *cmd = ucmd->cmd;
+	struct rb_root_cached allowed_iova = RB_ROOT_CACHED;
+	struct interval_tree_node *node;
+	struct iommufd_ioas *ioas;
+	struct io_pagetable *iopt;
+	int rc = 0;
+
+	ioas = iommufd_get_ioas(ucmd, cmd->ioas_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+	iopt = &ioas->iopt;
+
+	rc = iommufd_ioas_load_iovas(&allowed_iova,
+				      u64_to_user_ptr(cmd->allowed_iovas),
+				      cmd->num_iovas);
+	if (rc)
+		goto out_free;
+
+	rc = iopt_set_allow_iova(iopt, &allowed_iova);
+out_free:
+	while ((node = interval_tree_iter_first(&allowed_iova, 0, ULONG_MAX))) {
+		interval_tree_remove(node, &allowed_iova);
+		kfree(container_of(node, struct iopt_allowed, node));
+	}
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
+
+static int conv_iommu_prot(u32 map_flags)
+{
+	int iommu_prot;
+
+	/*
+	 * We provide no manual cache coherency ioctls to userspace and most
+	 * architectures make the CPU ops for cache flushing privileged.
+	 * Therefore we require the underlying IOMMU to support CPU coherent
+	 * operation. Support for IOMMU_CACHE is enforced by the
+	 * dev_is_dma_coherent() test during bind.
+	 */
+	iommu_prot = IOMMU_CACHE;
+	if (map_flags & IOMMU_IOAS_MAP_WRITEABLE)
+		iommu_prot |= IOMMU_WRITE;
+	if (map_flags & IOMMU_IOAS_MAP_READABLE)
+		iommu_prot |= IOMMU_READ;
+	return iommu_prot;
+}
+
+int iommufd_ioas_map(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_map *cmd = ucmd->cmd;
+	struct iommufd_ioas *ioas;
+	unsigned int flags = 0;
+	unsigned long iova;
+	int rc;
+
+	if ((cmd->flags &
+	     ~(IOMMU_IOAS_MAP_FIXED_IOVA | IOMMU_IOAS_MAP_WRITEABLE |
+	       IOMMU_IOAS_MAP_READABLE)) ||
+	    cmd->__reserved)
+		return -EOPNOTSUPP;
+	if (cmd->iova >= ULONG_MAX || cmd->length >= ULONG_MAX)
+		return -EOVERFLOW;
+
+	ioas = iommufd_get_ioas(ucmd, cmd->ioas_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	if (!(cmd->flags & IOMMU_IOAS_MAP_FIXED_IOVA))
+		flags = IOPT_ALLOC_IOVA;
+	iova = cmd->iova;
+	rc = iopt_map_user_pages(&ioas->iopt, &iova,
+				 u64_to_user_ptr(cmd->user_va), cmd->length,
+				 conv_iommu_prot(cmd->flags), flags);
+	if (rc)
+		goto out_put;
+
+	cmd->iova = iova;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+out_put:
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
+
+int iommufd_ioas_copy(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_copy *cmd = ucmd->cmd;
+	struct iommufd_ioas *src_ioas;
+	struct iommufd_ioas *dst_ioas;
+	struct iopt_pages *pages;
+	unsigned int flags = 0;
+	unsigned long iova;
+	unsigned long start_byte;
+	int rc;
+
+	if ((cmd->flags &
+	     ~(IOMMU_IOAS_MAP_FIXED_IOVA | IOMMU_IOAS_MAP_WRITEABLE |
+	       IOMMU_IOAS_MAP_READABLE)))
+		return -EOPNOTSUPP;
+	if (cmd->length >= ULONG_MAX)
+		return -EOVERFLOW;
+
+	src_ioas = iommufd_get_ioas(ucmd, cmd->src_ioas_id);
+	if (IS_ERR(src_ioas))
+		return PTR_ERR(src_ioas);
+	/* FIXME: copy is not limited to an exact match anymore */
+	pages = iopt_get_pages(&src_ioas->iopt, cmd->src_iova, &start_byte,
+			       cmd->length);
+	iommufd_put_object(&src_ioas->obj);
+	if (IS_ERR(pages))
+		return PTR_ERR(pages);
+
+	dst_ioas = iommufd_get_ioas(ucmd, cmd->dst_ioas_id);
+	if (IS_ERR(dst_ioas)) {
+		iopt_put_pages(pages);
+		return PTR_ERR(dst_ioas);
+	}
+
+	if (!(cmd->flags & IOMMU_IOAS_MAP_FIXED_IOVA))
+		flags = IOPT_ALLOC_IOVA;
+	iova = cmd->dst_iova;
+	rc = iopt_map_pages(&dst_ioas->iopt, pages, &iova, start_byte,
+			    cmd->length, conv_iommu_prot(cmd->flags), flags);
+	if (rc) {
+		iopt_put_pages(pages);
+		goto out_put_dst;
+	}
+
+	cmd->dst_iova = iova;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+out_put_dst:
+	iommufd_put_object(&dst_ioas->obj);
+	return rc;
+}
+
+int iommufd_ioas_unmap(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_unmap *cmd = ucmd->cmd;
+	struct iommufd_ioas *ioas;
+	unsigned long unmapped = 0;
+	int rc;
+
+	ioas = iommufd_get_ioas(ucmd, cmd->ioas_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	if (cmd->iova == 0 && cmd->length == U64_MAX) {
+		rc = iopt_unmap_all(&ioas->iopt, &unmapped);
+		if (rc)
+			goto out_put;
+	} else {
+		if (cmd->iova >= ULONG_MAX || cmd->length >= ULONG_MAX) {
+			rc = -EOVERFLOW;
+			goto out_put;
+		}
+		rc = iopt_unmap_iova(&ioas->iopt, cmd->iova, cmd->length,
+				     &unmapped);
+		if (rc)
+			goto out_put;
+	}
+
+	cmd->length = unmapped;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+
+out_put:
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 560ab06fbc3366..0ef6b9bf4916eb 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -92,6 +92,7 @@ static inline int iommufd_ucmd_respond(struct iommufd_ucmd *ucmd,
 enum iommufd_object_type {
 	IOMMUFD_OBJ_NONE,
 	IOMMUFD_OBJ_ANY = IOMMUFD_OBJ_NONE,
+	IOMMUFD_OBJ_IOAS,
 };
 
 /* Base struct for all objects with a userspace ID handle. */
@@ -163,4 +164,31 @@ struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx,
 			     type),                                            \
 		     typeof(*(ptr)), obj)
 
+/*
+ * The IO Address Space (IOAS) pagetable is a virtual page table backed by the
+ * io_pagetable object. It is a user controlled mapping of IOVA -> PFNs. The
+ * mapping is copied into all of the associated domains and made available to
+ * in-kernel users.
+ */
+struct iommufd_ioas {
+	struct iommufd_object obj;
+	struct io_pagetable iopt;
+};
+
+static inline struct iommufd_ioas *iommufd_get_ioas(struct iommufd_ucmd *ucmd,
+						    u32 id)
+{
+	return container_of(iommufd_get_object(ucmd->ictx, id,
+					       IOMMUFD_OBJ_IOAS),
+			    struct iommufd_ioas, obj);
+}
+
+struct iommufd_ioas *iommufd_ioas_alloc(struct iommufd_ctx *ictx);
+int iommufd_ioas_alloc_ioctl(struct iommufd_ucmd *ucmd);
+void iommufd_ioas_destroy(struct iommufd_object *obj);
+int iommufd_ioas_iova_ranges(struct iommufd_ucmd *ucmd);
+int iommufd_ioas_allow_iovas(struct iommufd_ucmd *ucmd);
+int iommufd_ioas_map(struct iommufd_ucmd *ucmd);
+int iommufd_ioas_copy(struct iommufd_ucmd *ucmd);
+int iommufd_ioas_unmap(struct iommufd_ucmd *ucmd);
 #endif
diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c
index a5b1e2302ba59d..55b42eeb141b20 100644
--- a/drivers/iommu/iommufd/main.c
+++ b/drivers/iommu/iommufd/main.c
@@ -204,6 +204,11 @@ static int iommufd_fops_release(struct inode *inode, struct file *filp)
 
 union ucmd_buffer {
 	struct iommu_destroy destroy;
+	struct iommu_ioas_alloc alloc;
+	struct iommu_ioas_allow_iovas allow_iovas;
+	struct iommu_ioas_iova_ranges iova_ranges;
+	struct iommu_ioas_map map;
+	struct iommu_ioas_unmap unmap;
 };
 
 struct iommufd_ioctl_op {
@@ -224,6 +229,18 @@ struct iommufd_ioctl_op {
 	}
 static struct iommufd_ioctl_op iommufd_ioctl_ops[] = {
 	IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id),
+	IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl,
+		 struct iommu_ioas_alloc, out_ioas_id),
+	IOCTL_OP(IOMMU_IOAS_ALLOW_IOVAS, iommufd_ioas_allow_iovas,
+		 struct iommu_ioas_allow_iovas, allowed_iovas),
+	IOCTL_OP(IOMMU_IOAS_COPY, iommufd_ioas_copy, struct iommu_ioas_copy,
+		 src_iova),
+	IOCTL_OP(IOMMU_IOAS_IOVA_RANGES, iommufd_ioas_iova_ranges,
+		 struct iommu_ioas_iova_ranges, __reserved),
+	IOCTL_OP(IOMMU_IOAS_MAP, iommufd_ioas_map, struct iommu_ioas_map,
+		 __reserved),
+	IOCTL_OP(IOMMU_IOAS_UNMAP, iommufd_ioas_unmap, struct iommu_ioas_unmap,
+		 length),
 };
 
 static long iommufd_fops_ioctl(struct file *filp, unsigned int cmd,
@@ -310,6 +327,9 @@ void iommufd_ctx_put(struct iommufd_ctx *ictx)
 EXPORT_SYMBOL_GPL(iommufd_ctx_put);
 
 static struct iommufd_object_ops iommufd_object_ops[] = {
+	[IOMMUFD_OBJ_IOAS] = {
+		.destroy = iommufd_ioas_destroy,
+	},
 };
 
 static struct miscdevice iommu_misc_dev = {
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 2f7f76ec6db4cb..b7b0ac4016bb70 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -37,6 +37,12 @@
 enum {
 	IOMMUFD_CMD_BASE = 0x80,
 	IOMMUFD_CMD_DESTROY = IOMMUFD_CMD_BASE,
+	IOMMUFD_CMD_IOAS_ALLOC,
+	IOMMUFD_CMD_IOAS_ALLOW_IOVAS,
+	IOMMUFD_CMD_IOAS_COPY,
+	IOMMUFD_CMD_IOAS_IOVA_RANGES,
+	IOMMUFD_CMD_IOAS_MAP,
+	IOMMUFD_CMD_IOAS_UNMAP,
 };
 
 /**
@@ -52,4 +58,186 @@ struct iommu_destroy {
 };
 #define IOMMU_DESTROY _IO(IOMMUFD_TYPE, IOMMUFD_CMD_DESTROY)
 
+/**
+ * struct iommu_ioas_alloc - ioctl(IOMMU_IOAS_ALLOC)
+ * @size: sizeof(struct iommu_ioas_alloc)
+ * @flags: Must be 0
+ * @out_ioas_id: Output IOAS ID for the allocated object
+ *
+ * Allocate an IO Address Space (IOAS) which holds an IO Virtual Address (IOVA)
+ * to memory mapping.
+ */
+struct iommu_ioas_alloc {
+	__u32 size;
+	__u32 flags;
+	__u32 out_ioas_id;
+};
+#define IOMMU_IOAS_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_ALLOC)
+
+/**
+ * struct iommu_iova_range
+ * @start: First IOVA
+ * @last: Inclusive last IOVA
+ *
+ * An interval in IOVA space.
+ */
+struct iommu_iova_range {
+	__aligned_u64 start;
+	__aligned_u64 last;
+};
+
+/**
+ * struct iommu_ioas_iova_ranges - ioctl(IOMMU_IOAS_IOVA_RANGES)
+ * @size: sizeof(struct iommu_ioas_iova_ranges)
+ * @ioas_id: IOAS ID to read ranges from
+ * @out_num_iovas: Output total number of ranges in the IOAS
+ * @__reserved: Must be 0
+ * @out_valid_iovas: Array of valid IOVA ranges. The array length is the smaller
+ *                   of out_num_iovas or the length implied by size.
+ * @out_valid_iovas.start: First IOVA in the allowed range
+ * @out_valid_iovas.last: Inclusive last IOVA in the allowed range
+ *
+ * Query an IOAS for ranges of allowed IOVAs. Mapping IOVA outside these ranges
+ * is not allowed. out_num_iovas will be set to the total number of iovas and
+ * the out_valid_iovas[] will be filled in as space permits. size should include
+ * the allocated flex array.
+ *
+ * The allowed ranges are dependent on the HW path the DMA operation takes, and
+ * can change during the lifetime of the IOAS. A fresh empty IOAS will have a
+ * full range, and each attached device will narrow the ranges based on that
+ * devices HW restrictions. Detatching a device can widen the ranges. Userspace
+ * should query ranges after every attach/detatch to know what IOVAs are valid
+ * for mapping.
+ */
+struct iommu_ioas_iova_ranges {
+	__u32 size;
+	__u32 ioas_id;
+	__u32 out_num_iovas;
+	__u32 __reserved;
+	struct iommu_valid_iovas {
+		__aligned_u64 start;
+		__aligned_u64 last;
+	} out_valid_iovas[];
+};
+#define IOMMU_IOAS_IOVA_RANGES _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_IOVA_RANGES)
+
+/**
+ * struct iommu_ioas_allow_iovas - ioctl(IOMMU_IOAS_ALLOW_IOVAS)
+ * @size: sizeof(struct iommu_ioas_allow_iovas)
+ * @ioas_id: IOAS ID to allow IOVAs from
+ * @allowed_iovas: Pointer to array of struct iommu_iova_range
+ *
+ * Ensure a range of IOVAs are always available for allocation. If this call
+ * succeeds then IOMMU_IOAS_IOVA_RANGES will never return a list of IOVA ranges
+ * that are narrower than the ranges provided here. This call will fail if
+ * IOMMU_IOAS_IOVA_RANGES is currently narrower than the given ranges.
+ *
+ * When an IOAS is first created the IOVA_RANGES will be maximally sized, and as
+ * devices are attached the IOVA will narrow based on the device restrictions.
+ * When an allowed range is specified any narrowing will be refused, ie device
+ * attachment can fail if the device requires limiting within the allowed range.
+ *
+ * Automatic IOVA allocation is also impacted by this call, it MAP will allocate
+ * within the allowed IOVAs if they are present.
+ *
+ * This call replaces the entire allowed list with the given list.
+ */
+struct iommu_ioas_allow_iovas {
+	__u32 size;
+	__u32 ioas_id;
+	__u32 num_iovas;
+	__u32 __reserved;
+	__aligned_u64 allowed_iovas;
+};
+#define IOMMU_IOAS_ALLOW_IOVAS _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_ALLOW_IOVAS)
+
+/**
+ * enum iommufd_ioas_map_flags - Flags for map and copy
+ * @IOMMU_IOAS_MAP_FIXED_IOVA: If clear the kernel will compute an appropriate
+ *                             IOVA to place the mapping at
+ * @IOMMU_IOAS_MAP_WRITEABLE: DMA is allowed to write to this mapping
+ * @IOMMU_IOAS_MAP_READABLE: DMA is allowed to read from this mapping
+ */
+enum iommufd_ioas_map_flags {
+	IOMMU_IOAS_MAP_FIXED_IOVA = 1 << 0,
+	IOMMU_IOAS_MAP_WRITEABLE = 1 << 1,
+	IOMMU_IOAS_MAP_READABLE = 1 << 2,
+};
+
+/**
+ * struct iommu_ioas_map - ioctl(IOMMU_IOAS_MAP)
+ * @size: sizeof(struct iommu_ioas_map)
+ * @flags: Combination of enum iommufd_ioas_map_flags
+ * @ioas_id: IOAS ID to change the mapping of
+ * @__reserved: Must be 0
+ * @user_va: Userspace pointer to start mapping from
+ * @length: Number of bytes to map
+ * @iova: IOVA the mapping was placed at. If IOMMU_IOAS_MAP_FIXED_IOVA is set
+ *        then this must be provided as input.
+ *
+ * Set an IOVA mapping from a user pointer. If FIXED_IOVA is specified then the
+ * mapping will be established at iova, otherwise a suitable location will be
+ * automatically selected and returned in iova.
+ */
+struct iommu_ioas_map {
+	__u32 size;
+	__u32 flags;
+	__u32 ioas_id;
+	__u32 __reserved;
+	__aligned_u64 user_va;
+	__aligned_u64 length;
+	__aligned_u64 iova;
+};
+#define IOMMU_IOAS_MAP _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_MAP)
+
+/**
+ * struct iommu_ioas_copy - ioctl(IOMMU_IOAS_COPY)
+ * @size: sizeof(struct iommu_ioas_copy)
+ * @flags: Combination of enum iommufd_ioas_map_flags
+ * @dst_ioas_id: IOAS ID to change the mapping of
+ * @src_ioas_id: IOAS ID to copy from
+ * @length: Number of bytes to copy and map
+ * @dst_iova: IOVA the mapping was placed at. If IOMMU_IOAS_MAP_FIXED_IOVA is
+ *            set then this must be provided as input.
+ * @src_iova: IOVA to start the copy
+ *
+ * Copy an already existing mapping from src_ioas_id and establish it in
+ * dst_ioas_id. The src iova/length must exactly match a range used with
+ * IOMMU_IOAS_MAP.
+ *
+ * This may be used to efficiently clone a subset of an IOAS to another, or as a
+ * kind of 'cache' to speed up mapping. Copy has an effciency advantage over
+ * establishing equivilant new mappings, as internal resources are shared, and
+ * the kernel will pin the user memory only once.
+ */
+struct iommu_ioas_copy {
+	__u32 size;
+	__u32 flags;
+	__u32 dst_ioas_id;
+	__u32 src_ioas_id;
+	__aligned_u64 length;
+	__aligned_u64 dst_iova;
+	__aligned_u64 src_iova;
+};
+#define IOMMU_IOAS_COPY _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_COPY)
+
+/**
+ * struct iommu_ioas_unmap - ioctl(IOMMU_IOAS_UNMAP)
+ * @size: sizeof(struct iommu_ioas_copy)
+ * @ioas_id: IOAS ID to change the mapping of
+ * @iova: IOVA to start the unmapping at
+ * @length: Number of bytes to unmap, and return back the bytes unmapped
+ *
+ * Unmap an IOVA range. The iova/length must be a superset of a previously
+ * mapped range used with IOMMU_IOAS_PAGETABLE_MAP or COPY. Splitting or
+ * truncating ranges is not allowed. The values 0 to U64_MAX will unmap
+ * everything.
+ */
+struct iommu_ioas_unmap {
+	__u32 size;
+	__u32 ioas_id;
+	__aligned_u64 iova;
+	__aligned_u64 length;
+};
+#define IOMMU_IOAS_UNMAP _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_UNMAP)
 #endif
-- 
2.37.3


WARNING: multiple messages have this Message-ID (diff)
From: Jason Gunthorpe <jgg@nvidia.com>
Cc: Alex Williamson <alex.williamson@redhat.com>,
	Lu Baolu <baolu.lu@linux.intel.com>,
	Chaitanya Kulkarni <chaitanyak@nvidia.com>,
	Cornelia Huck <cohuck@redhat.com>,
	Daniel Jordan <daniel.m.jordan@oracle.com>,
	David Gibson <david@gibson.dropbear.id.au>,
	Eric Auger <eric.auger@redhat.com>,
	Eric Farman <farman@linux.ibm.com>,
	iommu@lists.linux.dev, Jason Wang <jasowang@redhat.com>,
	Jean-Philippe Brucker <jean-philippe@linaro.org>,
	Joao Martins <joao.m.martins@oracle.com>,
	Kevin Tian <kevin.tian@intel.com>,
	kvm@vger.kernel.org, Matthew Rosato <mjrosato@linux.ibm.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Nicolin Chen <nicolinc@nvidia.com>,
	Niklas Schnelle <schnelle@linux.ibm.com>,
	Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>,
	Yi Liu <yi.l.liu@intel.com>, Keqian Zhu <zhukeqian1@huawei.com>
Subject: [PATCH RFC v2 08/13] iommufd: IOCTLs for the io_pagetable
Date: Fri,  2 Sep 2022 16:59:24 -0300	[thread overview]
Message-ID: <8-v2-f9436d0bde78+4bb-iommufd_jgg@nvidia.com> (raw)
In-Reply-To: <0-v2-f9436d0bde78+4bb-iommufd_jgg@nvidia.com>

Connect the IOAS to its IOCTL interface. This exposes most of the
functionality in the io_pagetable to userspace.

This is intended to be the core of the generic interface that IOMMUFD will
provide. Every IOMMU driver should be able to implement an iommu_domain
that is compatible with this generic mechanism.

It is also designed to be easy to use for simple non virtual machine
monitor users, like DPDK:
 - Universal simple support for all IOMMUs (no PPC special path)
 - An IOVA allocator that considers the aperture and the allowed/reserved
   ranges
 - io_pagetable allows any number of iommu_domains to be connected to the
   IOAS

Along with room in the design to add non-generic features to cater to
specific HW functionality.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
 drivers/iommu/iommufd/Makefile          |   1 +
 drivers/iommu/iommufd/ioas.c            | 316 ++++++++++++++++++++++++
 drivers/iommu/iommufd/iommufd_private.h |  28 +++
 drivers/iommu/iommufd/main.c            |  20 ++
 include/uapi/linux/iommufd.h            | 188 ++++++++++++++
 5 files changed, 553 insertions(+)
 create mode 100644 drivers/iommu/iommufd/ioas.c

diff --git a/drivers/iommu/iommufd/Makefile b/drivers/iommu/iommufd/Makefile
index b66a8c47ff55ec..2b4f36f1b72f9d 100644
--- a/drivers/iommu/iommufd/Makefile
+++ b/drivers/iommu/iommufd/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 iommufd-y := \
 	io_pagetable.o \
+	ioas.o \
 	main.o \
 	pages.o
 
diff --git a/drivers/iommu/iommufd/ioas.c b/drivers/iommu/iommufd/ioas.c
new file mode 100644
index 00000000000000..f9f545158a4891
--- /dev/null
+++ b/drivers/iommu/iommufd/ioas.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES
+ */
+#include <linux/interval_tree.h>
+#include <linux/iommufd.h>
+#include <linux/iommu.h>
+#include <uapi/linux/iommufd.h>
+
+#include "io_pagetable.h"
+
+void iommufd_ioas_destroy(struct iommufd_object *obj)
+{
+	struct iommufd_ioas *ioas = container_of(obj, struct iommufd_ioas, obj);
+	int rc;
+
+	rc = iopt_unmap_all(&ioas->iopt, NULL);
+	WARN_ON(rc && rc != -ENOENT);
+	iopt_destroy_table(&ioas->iopt);
+}
+
+struct iommufd_ioas *iommufd_ioas_alloc(struct iommufd_ctx *ictx)
+{
+	struct iommufd_ioas *ioas;
+	int rc;
+
+	ioas = iommufd_object_alloc(ictx, ioas, IOMMUFD_OBJ_IOAS);
+	if (IS_ERR(ioas))
+		return ioas;
+
+	rc = iopt_init_table(&ioas->iopt);
+	if (rc)
+		goto out_abort;
+	return ioas;
+
+out_abort:
+	iommufd_object_abort(ictx, &ioas->obj);
+	return ERR_PTR(rc);
+}
+
+int iommufd_ioas_alloc_ioctl(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_alloc *cmd = ucmd->cmd;
+	struct iommufd_ioas *ioas;
+	int rc;
+
+	if (cmd->flags)
+		return -EOPNOTSUPP;
+
+	ioas = iommufd_ioas_alloc(ucmd->ictx);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	cmd->out_ioas_id = ioas->obj.id;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+	if (rc)
+		goto out_table;
+	iommufd_object_finalize(ucmd->ictx, &ioas->obj);
+	return 0;
+
+out_table:
+	iommufd_ioas_destroy(&ioas->obj);
+	return rc;
+}
+
+int iommufd_ioas_iova_ranges(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_iova_ranges __user *uptr = ucmd->ubuffer;
+	struct iommu_ioas_iova_ranges *cmd = ucmd->cmd;
+	struct iommufd_ioas *ioas;
+	struct interval_tree_span_iter span;
+	u32 max_iovas;
+	int rc;
+
+	if (cmd->__reserved)
+		return -EOPNOTSUPP;
+
+	max_iovas = cmd->size - sizeof(*cmd);
+	if (max_iovas % sizeof(cmd->out_valid_iovas[0]))
+		return -EINVAL;
+	max_iovas /= sizeof(cmd->out_valid_iovas[0]);
+
+	ioas = iommufd_get_ioas(ucmd, cmd->ioas_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	down_read(&ioas->iopt.iova_rwsem);
+	cmd->out_num_iovas = 0;
+	interval_tree_for_each_span (&span, &ioas->iopt.reserved_itree,
+				     0, ULONG_MAX) {
+		if (!span.is_hole)
+			continue;
+		if (cmd->out_num_iovas < max_iovas) {
+			rc = put_user((u64)span.start_hole,
+				      &uptr->out_valid_iovas[cmd->out_num_iovas]
+					       .start);
+			if (rc)
+				goto out_put;
+			rc = put_user(
+				(u64)span.last_hole,
+				&uptr->out_valid_iovas[cmd->out_num_iovas].last);
+			if (rc)
+				goto out_put;
+		}
+		cmd->out_num_iovas++;
+	}
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+	if (rc)
+		goto out_put;
+	if (cmd->out_num_iovas > max_iovas)
+		rc = -EMSGSIZE;
+out_put:
+	up_read(&ioas->iopt.iova_rwsem);
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
+
+static int iommufd_ioas_load_iovas(struct rb_root_cached *itree,
+				   struct iommu_iova_range __user *ranges,
+				   u32 num)
+{
+	u32 i;
+
+	for (i = 0; i != num; i++) {
+		struct iommu_iova_range range;
+		struct iopt_allowed *allowed;
+
+		if (copy_from_user(&range, ranges + i, sizeof(range)))
+			return -EFAULT;
+
+		if (range.start >= range.last)
+			return -EINVAL;
+
+		if (interval_tree_iter_first(itree, range.start, range.last))
+			return -EINVAL;
+
+		allowed = kzalloc(sizeof(*allowed), GFP_KERNEL_ACCOUNT);
+		if (!allowed)
+			return -ENOMEM;
+		allowed->node.start = range.start;
+		allowed->node.last = range.last;
+
+		interval_tree_insert(&allowed->node, itree);
+	}
+	return 0;
+}
+
+int iommufd_ioas_allow_iovas(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_allow_iovas *cmd = ucmd->cmd;
+	struct rb_root_cached allowed_iova = RB_ROOT_CACHED;
+	struct interval_tree_node *node;
+	struct iommufd_ioas *ioas;
+	struct io_pagetable *iopt;
+	int rc = 0;
+
+	ioas = iommufd_get_ioas(ucmd, cmd->ioas_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+	iopt = &ioas->iopt;
+
+	rc = iommufd_ioas_load_iovas(&allowed_iova,
+				      u64_to_user_ptr(cmd->allowed_iovas),
+				      cmd->num_iovas);
+	if (rc)
+		goto out_free;
+
+	rc = iopt_set_allow_iova(iopt, &allowed_iova);
+out_free:
+	while ((node = interval_tree_iter_first(&allowed_iova, 0, ULONG_MAX))) {
+		interval_tree_remove(node, &allowed_iova);
+		kfree(container_of(node, struct iopt_allowed, node));
+	}
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
+
+static int conv_iommu_prot(u32 map_flags)
+{
+	int iommu_prot;
+
+	/*
+	 * We provide no manual cache coherency ioctls to userspace and most
+	 * architectures make the CPU ops for cache flushing privileged.
+	 * Therefore we require the underlying IOMMU to support CPU coherent
+	 * operation. Support for IOMMU_CACHE is enforced by the
+	 * dev_is_dma_coherent() test during bind.
+	 */
+	iommu_prot = IOMMU_CACHE;
+	if (map_flags & IOMMU_IOAS_MAP_WRITEABLE)
+		iommu_prot |= IOMMU_WRITE;
+	if (map_flags & IOMMU_IOAS_MAP_READABLE)
+		iommu_prot |= IOMMU_READ;
+	return iommu_prot;
+}
+
+int iommufd_ioas_map(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_map *cmd = ucmd->cmd;
+	struct iommufd_ioas *ioas;
+	unsigned int flags = 0;
+	unsigned long iova;
+	int rc;
+
+	if ((cmd->flags &
+	     ~(IOMMU_IOAS_MAP_FIXED_IOVA | IOMMU_IOAS_MAP_WRITEABLE |
+	       IOMMU_IOAS_MAP_READABLE)) ||
+	    cmd->__reserved)
+		return -EOPNOTSUPP;
+	if (cmd->iova >= ULONG_MAX || cmd->length >= ULONG_MAX)
+		return -EOVERFLOW;
+
+	ioas = iommufd_get_ioas(ucmd, cmd->ioas_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	if (!(cmd->flags & IOMMU_IOAS_MAP_FIXED_IOVA))
+		flags = IOPT_ALLOC_IOVA;
+	iova = cmd->iova;
+	rc = iopt_map_user_pages(&ioas->iopt, &iova,
+				 u64_to_user_ptr(cmd->user_va), cmd->length,
+				 conv_iommu_prot(cmd->flags), flags);
+	if (rc)
+		goto out_put;
+
+	cmd->iova = iova;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+out_put:
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
+
+int iommufd_ioas_copy(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_copy *cmd = ucmd->cmd;
+	struct iommufd_ioas *src_ioas;
+	struct iommufd_ioas *dst_ioas;
+	struct iopt_pages *pages;
+	unsigned int flags = 0;
+	unsigned long iova;
+	unsigned long start_byte;
+	int rc;
+
+	if ((cmd->flags &
+	     ~(IOMMU_IOAS_MAP_FIXED_IOVA | IOMMU_IOAS_MAP_WRITEABLE |
+	       IOMMU_IOAS_MAP_READABLE)))
+		return -EOPNOTSUPP;
+	if (cmd->length >= ULONG_MAX)
+		return -EOVERFLOW;
+
+	src_ioas = iommufd_get_ioas(ucmd, cmd->src_ioas_id);
+	if (IS_ERR(src_ioas))
+		return PTR_ERR(src_ioas);
+	/* FIXME: copy is not limited to an exact match anymore */
+	pages = iopt_get_pages(&src_ioas->iopt, cmd->src_iova, &start_byte,
+			       cmd->length);
+	iommufd_put_object(&src_ioas->obj);
+	if (IS_ERR(pages))
+		return PTR_ERR(pages);
+
+	dst_ioas = iommufd_get_ioas(ucmd, cmd->dst_ioas_id);
+	if (IS_ERR(dst_ioas)) {
+		iopt_put_pages(pages);
+		return PTR_ERR(dst_ioas);
+	}
+
+	if (!(cmd->flags & IOMMU_IOAS_MAP_FIXED_IOVA))
+		flags = IOPT_ALLOC_IOVA;
+	iova = cmd->dst_iova;
+	rc = iopt_map_pages(&dst_ioas->iopt, pages, &iova, start_byte,
+			    cmd->length, conv_iommu_prot(cmd->flags), flags);
+	if (rc) {
+		iopt_put_pages(pages);
+		goto out_put_dst;
+	}
+
+	cmd->dst_iova = iova;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+out_put_dst:
+	iommufd_put_object(&dst_ioas->obj);
+	return rc;
+}
+
+int iommufd_ioas_unmap(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_ioas_unmap *cmd = ucmd->cmd;
+	struct iommufd_ioas *ioas;
+	unsigned long unmapped = 0;
+	int rc;
+
+	ioas = iommufd_get_ioas(ucmd, cmd->ioas_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	if (cmd->iova == 0 && cmd->length == U64_MAX) {
+		rc = iopt_unmap_all(&ioas->iopt, &unmapped);
+		if (rc)
+			goto out_put;
+	} else {
+		if (cmd->iova >= ULONG_MAX || cmd->length >= ULONG_MAX) {
+			rc = -EOVERFLOW;
+			goto out_put;
+		}
+		rc = iopt_unmap_iova(&ioas->iopt, cmd->iova, cmd->length,
+				     &unmapped);
+		if (rc)
+			goto out_put;
+	}
+
+	cmd->length = unmapped;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+
+out_put:
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 560ab06fbc3366..0ef6b9bf4916eb 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -92,6 +92,7 @@ static inline int iommufd_ucmd_respond(struct iommufd_ucmd *ucmd,
 enum iommufd_object_type {
 	IOMMUFD_OBJ_NONE,
 	IOMMUFD_OBJ_ANY = IOMMUFD_OBJ_NONE,
+	IOMMUFD_OBJ_IOAS,
 };
 
 /* Base struct for all objects with a userspace ID handle. */
@@ -163,4 +164,31 @@ struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx,
 			     type),                                            \
 		     typeof(*(ptr)), obj)
 
+/*
+ * The IO Address Space (IOAS) pagetable is a virtual page table backed by the
+ * io_pagetable object. It is a user controlled mapping of IOVA -> PFNs. The
+ * mapping is copied into all of the associated domains and made available to
+ * in-kernel users.
+ */
+struct iommufd_ioas {
+	struct iommufd_object obj;
+	struct io_pagetable iopt;
+};
+
+static inline struct iommufd_ioas *iommufd_get_ioas(struct iommufd_ucmd *ucmd,
+						    u32 id)
+{
+	return container_of(iommufd_get_object(ucmd->ictx, id,
+					       IOMMUFD_OBJ_IOAS),
+			    struct iommufd_ioas, obj);
+}
+
+struct iommufd_ioas *iommufd_ioas_alloc(struct iommufd_ctx *ictx);
+int iommufd_ioas_alloc_ioctl(struct iommufd_ucmd *ucmd);
+void iommufd_ioas_destroy(struct iommufd_object *obj);
+int iommufd_ioas_iova_ranges(struct iommufd_ucmd *ucmd);
+int iommufd_ioas_allow_iovas(struct iommufd_ucmd *ucmd);
+int iommufd_ioas_map(struct iommufd_ucmd *ucmd);
+int iommufd_ioas_copy(struct iommufd_ucmd *ucmd);
+int iommufd_ioas_unmap(struct iommufd_ucmd *ucmd);
 #endif
diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c
index a5b1e2302ba59d..55b42eeb141b20 100644
--- a/drivers/iommu/iommufd/main.c
+++ b/drivers/iommu/iommufd/main.c
@@ -204,6 +204,11 @@ static int iommufd_fops_release(struct inode *inode, struct file *filp)
 
 union ucmd_buffer {
 	struct iommu_destroy destroy;
+	struct iommu_ioas_alloc alloc;
+	struct iommu_ioas_allow_iovas allow_iovas;
+	struct iommu_ioas_iova_ranges iova_ranges;
+	struct iommu_ioas_map map;
+	struct iommu_ioas_unmap unmap;
 };
 
 struct iommufd_ioctl_op {
@@ -224,6 +229,18 @@ struct iommufd_ioctl_op {
 	}
 static struct iommufd_ioctl_op iommufd_ioctl_ops[] = {
 	IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id),
+	IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl,
+		 struct iommu_ioas_alloc, out_ioas_id),
+	IOCTL_OP(IOMMU_IOAS_ALLOW_IOVAS, iommufd_ioas_allow_iovas,
+		 struct iommu_ioas_allow_iovas, allowed_iovas),
+	IOCTL_OP(IOMMU_IOAS_COPY, iommufd_ioas_copy, struct iommu_ioas_copy,
+		 src_iova),
+	IOCTL_OP(IOMMU_IOAS_IOVA_RANGES, iommufd_ioas_iova_ranges,
+		 struct iommu_ioas_iova_ranges, __reserved),
+	IOCTL_OP(IOMMU_IOAS_MAP, iommufd_ioas_map, struct iommu_ioas_map,
+		 __reserved),
+	IOCTL_OP(IOMMU_IOAS_UNMAP, iommufd_ioas_unmap, struct iommu_ioas_unmap,
+		 length),
 };
 
 static long iommufd_fops_ioctl(struct file *filp, unsigned int cmd,
@@ -310,6 +327,9 @@ void iommufd_ctx_put(struct iommufd_ctx *ictx)
 EXPORT_SYMBOL_GPL(iommufd_ctx_put);
 
 static struct iommufd_object_ops iommufd_object_ops[] = {
+	[IOMMUFD_OBJ_IOAS] = {
+		.destroy = iommufd_ioas_destroy,
+	},
 };
 
 static struct miscdevice iommu_misc_dev = {
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 2f7f76ec6db4cb..b7b0ac4016bb70 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -37,6 +37,12 @@
 enum {
 	IOMMUFD_CMD_BASE = 0x80,
 	IOMMUFD_CMD_DESTROY = IOMMUFD_CMD_BASE,
+	IOMMUFD_CMD_IOAS_ALLOC,
+	IOMMUFD_CMD_IOAS_ALLOW_IOVAS,
+	IOMMUFD_CMD_IOAS_COPY,
+	IOMMUFD_CMD_IOAS_IOVA_RANGES,
+	IOMMUFD_CMD_IOAS_MAP,
+	IOMMUFD_CMD_IOAS_UNMAP,
 };
 
 /**
@@ -52,4 +58,186 @@ struct iommu_destroy {
 };
 #define IOMMU_DESTROY _IO(IOMMUFD_TYPE, IOMMUFD_CMD_DESTROY)
 
+/**
+ * struct iommu_ioas_alloc - ioctl(IOMMU_IOAS_ALLOC)
+ * @size: sizeof(struct iommu_ioas_alloc)
+ * @flags: Must be 0
+ * @out_ioas_id: Output IOAS ID for the allocated object
+ *
+ * Allocate an IO Address Space (IOAS) which holds an IO Virtual Address (IOVA)
+ * to memory mapping.
+ */
+struct iommu_ioas_alloc {
+	__u32 size;
+	__u32 flags;
+	__u32 out_ioas_id;
+};
+#define IOMMU_IOAS_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_ALLOC)
+
+/**
+ * struct iommu_iova_range
+ * @start: First IOVA
+ * @last: Inclusive last IOVA
+ *
+ * An interval in IOVA space.
+ */
+struct iommu_iova_range {
+	__aligned_u64 start;
+	__aligned_u64 last;
+};
+
+/**
+ * struct iommu_ioas_iova_ranges - ioctl(IOMMU_IOAS_IOVA_RANGES)
+ * @size: sizeof(struct iommu_ioas_iova_ranges)
+ * @ioas_id: IOAS ID to read ranges from
+ * @out_num_iovas: Output total number of ranges in the IOAS
+ * @__reserved: Must be 0
+ * @out_valid_iovas: Array of valid IOVA ranges. The array length is the smaller
+ *                   of out_num_iovas or the length implied by size.
+ * @out_valid_iovas.start: First IOVA in the allowed range
+ * @out_valid_iovas.last: Inclusive last IOVA in the allowed range
+ *
+ * Query an IOAS for ranges of allowed IOVAs. Mapping IOVA outside these ranges
+ * is not allowed. out_num_iovas will be set to the total number of iovas and
+ * the out_valid_iovas[] will be filled in as space permits. size should include
+ * the allocated flex array.
+ *
+ * The allowed ranges are dependent on the HW path the DMA operation takes, and
+ * can change during the lifetime of the IOAS. A fresh empty IOAS will have a
+ * full range, and each attached device will narrow the ranges based on that
+ * devices HW restrictions. Detatching a device can widen the ranges. Userspace
+ * should query ranges after every attach/detatch to know what IOVAs are valid
+ * for mapping.
+ */
+struct iommu_ioas_iova_ranges {
+	__u32 size;
+	__u32 ioas_id;
+	__u32 out_num_iovas;
+	__u32 __reserved;
+	struct iommu_valid_iovas {
+		__aligned_u64 start;
+		__aligned_u64 last;
+	} out_valid_iovas[];
+};
+#define IOMMU_IOAS_IOVA_RANGES _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_IOVA_RANGES)
+
+/**
+ * struct iommu_ioas_allow_iovas - ioctl(IOMMU_IOAS_ALLOW_IOVAS)
+ * @size: sizeof(struct iommu_ioas_allow_iovas)
+ * @ioas_id: IOAS ID to allow IOVAs from
+ * @allowed_iovas: Pointer to array of struct iommu_iova_range
+ *
+ * Ensure a range of IOVAs are always available for allocation. If this call
+ * succeeds then IOMMU_IOAS_IOVA_RANGES will never return a list of IOVA ranges
+ * that are narrower than the ranges provided here. This call will fail if
+ * IOMMU_IOAS_IOVA_RANGES is currently narrower than the given ranges.
+ *
+ * When an IOAS is first created the IOVA_RANGES will be maximally sized, and as
+ * devices are attached the IOVA will narrow based on the device restrictions.
+ * When an allowed range is specified any narrowing will be refused, ie device
+ * attachment can fail if the device requires limiting within the allowed range.
+ *
+ * Automatic IOVA allocation is also impacted by this call, it MAP will allocate
+ * within the allowed IOVAs if they are present.
+ *
+ * This call replaces the entire allowed list with the given list.
+ */
+struct iommu_ioas_allow_iovas {
+	__u32 size;
+	__u32 ioas_id;
+	__u32 num_iovas;
+	__u32 __reserved;
+	__aligned_u64 allowed_iovas;
+};
+#define IOMMU_IOAS_ALLOW_IOVAS _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_ALLOW_IOVAS)
+
+/**
+ * enum iommufd_ioas_map_flags - Flags for map and copy
+ * @IOMMU_IOAS_MAP_FIXED_IOVA: If clear the kernel will compute an appropriate
+ *                             IOVA to place the mapping at
+ * @IOMMU_IOAS_MAP_WRITEABLE: DMA is allowed to write to this mapping
+ * @IOMMU_IOAS_MAP_READABLE: DMA is allowed to read from this mapping
+ */
+enum iommufd_ioas_map_flags {
+	IOMMU_IOAS_MAP_FIXED_IOVA = 1 << 0,
+	IOMMU_IOAS_MAP_WRITEABLE = 1 << 1,
+	IOMMU_IOAS_MAP_READABLE = 1 << 2,
+};
+
+/**
+ * struct iommu_ioas_map - ioctl(IOMMU_IOAS_MAP)
+ * @size: sizeof(struct iommu_ioas_map)
+ * @flags: Combination of enum iommufd_ioas_map_flags
+ * @ioas_id: IOAS ID to change the mapping of
+ * @__reserved: Must be 0
+ * @user_va: Userspace pointer to start mapping from
+ * @length: Number of bytes to map
+ * @iova: IOVA the mapping was placed at. If IOMMU_IOAS_MAP_FIXED_IOVA is set
+ *        then this must be provided as input.
+ *
+ * Set an IOVA mapping from a user pointer. If FIXED_IOVA is specified then the
+ * mapping will be established at iova, otherwise a suitable location will be
+ * automatically selected and returned in iova.
+ */
+struct iommu_ioas_map {
+	__u32 size;
+	__u32 flags;
+	__u32 ioas_id;
+	__u32 __reserved;
+	__aligned_u64 user_va;
+	__aligned_u64 length;
+	__aligned_u64 iova;
+};
+#define IOMMU_IOAS_MAP _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_MAP)
+
+/**
+ * struct iommu_ioas_copy - ioctl(IOMMU_IOAS_COPY)
+ * @size: sizeof(struct iommu_ioas_copy)
+ * @flags: Combination of enum iommufd_ioas_map_flags
+ * @dst_ioas_id: IOAS ID to change the mapping of
+ * @src_ioas_id: IOAS ID to copy from
+ * @length: Number of bytes to copy and map
+ * @dst_iova: IOVA the mapping was placed at. If IOMMU_IOAS_MAP_FIXED_IOVA is
+ *            set then this must be provided as input.
+ * @src_iova: IOVA to start the copy
+ *
+ * Copy an already existing mapping from src_ioas_id and establish it in
+ * dst_ioas_id. The src iova/length must exactly match a range used with
+ * IOMMU_IOAS_MAP.
+ *
+ * This may be used to efficiently clone a subset of an IOAS to another, or as a
+ * kind of 'cache' to speed up mapping. Copy has an effciency advantage over
+ * establishing equivilant new mappings, as internal resources are shared, and
+ * the kernel will pin the user memory only once.
+ */
+struct iommu_ioas_copy {
+	__u32 size;
+	__u32 flags;
+	__u32 dst_ioas_id;
+	__u32 src_ioas_id;
+	__aligned_u64 length;
+	__aligned_u64 dst_iova;
+	__aligned_u64 src_iova;
+};
+#define IOMMU_IOAS_COPY _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_COPY)
+
+/**
+ * struct iommu_ioas_unmap - ioctl(IOMMU_IOAS_UNMAP)
+ * @size: sizeof(struct iommu_ioas_copy)
+ * @ioas_id: IOAS ID to change the mapping of
+ * @iova: IOVA to start the unmapping at
+ * @length: Number of bytes to unmap, and return back the bytes unmapped
+ *
+ * Unmap an IOVA range. The iova/length must be a superset of a previously
+ * mapped range used with IOMMU_IOAS_PAGETABLE_MAP or COPY. Splitting or
+ * truncating ranges is not allowed. The values 0 to U64_MAX will unmap
+ * everything.
+ */
+struct iommu_ioas_unmap {
+	__u32 size;
+	__u32 ioas_id;
+	__aligned_u64 iova;
+	__aligned_u64 length;
+};
+#define IOMMU_IOAS_UNMAP _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_UNMAP)
 #endif
-- 
2.37.3


  parent reply	other threads:[~2022-09-02 19:59 UTC|newest]

Thread overview: 78+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-02 19:59 [PATCH RFC v2 00/13] IOMMUFD Generic interface Jason Gunthorpe
2022-09-02 19:59 ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 01/13] interval-tree: Add a utility to iterate over spans in an interval tree Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 02/13] iommufd: Overview documentation Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-07  1:39   ` David Gibson
2022-09-09 18:52     ` Jason Gunthorpe
2022-09-12 10:40       ` David Gibson
2022-09-27 17:33         ` Jason Gunthorpe
2022-09-29  3:47           ` David Gibson
2022-09-02 19:59 ` [PATCH RFC v2 03/13] iommufd: File descriptor, context, kconfig and makefiles Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-04  8:19   ` Baolu Lu
2022-09-09 18:46     ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 04/13] kernel/user: Allow user::locked_vm to be usable for iommufd Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 05/13] iommufd: PFN handling for iopt_pages Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 06/13] iommufd: Algorithms for PFN storage Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 07/13] iommufd: Data structure to provide IOVA to PFN mapping Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` Jason Gunthorpe [this message]
2022-09-02 19:59   ` [PATCH RFC v2 08/13] iommufd: IOCTLs for the io_pagetable Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 09/13] iommufd: Add a HW pagetable object Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 10/13] iommufd: Add kAPI toward external drivers for physical devices Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 11/13] iommufd: Add kAPI toward external drivers for kernel access Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 12/13] iommufd: vfio container FD ioctl compatibility Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-02 19:59 ` [PATCH RFC v2 13/13] iommufd: Add a selftest Jason Gunthorpe
2022-09-02 19:59   ` Jason Gunthorpe
2022-09-13  1:55 ` [PATCH RFC v2 00/13] IOMMUFD Generic interface Tian, Kevin
2022-09-13  7:28   ` Eric Auger
2022-09-20 19:56     ` Jason Gunthorpe
2022-09-21  3:48       ` Tian, Kevin
2022-09-21 18:06       ` Alex Williamson
2022-09-21 18:44         ` Jason Gunthorpe
2022-09-21 19:30           ` Steven Sistare
2022-09-21 23:09             ` Jason Gunthorpe
2022-10-06 16:01               ` Jason Gunthorpe
2022-10-06 22:57                 ` Steven Sistare
2022-10-10 20:54                 ` Steven Sistare
2022-10-11 12:30                   ` Jason Gunthorpe
2022-10-11 20:30                     ` Steven Sistare
2022-10-12 12:32                       ` Jason Gunthorpe
2022-10-12 13:50                         ` Steven Sistare
2022-10-12 14:40                           ` Jason Gunthorpe
2022-10-12 14:55                             ` Steven Sistare
2022-10-12 14:59                               ` Jason Gunthorpe
2022-09-21 23:20           ` Jason Gunthorpe
2022-09-22 11:20           ` Daniel P. Berrangé
2022-09-22 14:08             ` Jason Gunthorpe
2022-09-22 14:49               ` Daniel P. Berrangé
2022-09-22 14:51                 ` Jason Gunthorpe
2022-09-22 15:00                   ` Daniel P. Berrangé
2022-09-22 15:31                     ` Jason Gunthorpe
2022-09-23  8:54                       ` Daniel P. Berrangé
2022-09-23 13:29                         ` Jason Gunthorpe
2022-09-23 13:35                           ` Daniel P. Berrangé
2022-09-23 13:46                             ` Jason Gunthorpe
2022-09-23 14:00                               ` Daniel P. Berrangé
2022-09-23 15:40                                 ` Laine Stump
2022-10-21 19:56                                   ` Jason Gunthorpe
2022-09-23 14:03                           ` Alex Williamson
2022-09-26  6:34                             ` David Gibson
2022-09-21 22:36         ` Laine Stump
2022-09-22 11:06         ` Daniel P. Berrangé
2022-09-22 14:13           ` Jason Gunthorpe
2022-09-22 14:46             ` Daniel P. Berrangé
2022-09-13  2:05 ` Tian, Kevin
2022-09-20 20:07   ` Jason Gunthorpe
2022-09-21  3:40     ` Tian, Kevin
2022-09-21 16:19       ` Jason Gunthorpe
2022-09-26 13:48     ` Rodel, Jorg

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=8-v2-f9436d0bde78+4bb-iommufd_jgg@nvidia.com \
    --to=jgg@nvidia.com \
    --cc=alex.williamson@redhat.com \
    --cc=baolu.lu@linux.intel.com \
    --cc=chaitanyak@nvidia.com \
    --cc=cohuck@redhat.com \
    --cc=daniel.m.jordan@oracle.com \
    --cc=david@gibson.dropbear.id.au \
    --cc=eric.auger@redhat.com \
    --cc=farman@linux.ibm.com \
    --cc=iommu@lists.linux.dev \
    --cc=jasowang@redhat.com \
    --cc=jean-philippe@linaro.org \
    --cc=joao.m.martins@oracle.com \
    --cc=kevin.tian@intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=mjrosato@linux.ibm.com \
    --cc=mst@redhat.com \
    --cc=nicolinc@nvidia.com \
    --cc=schnelle@linux.ibm.com \
    --cc=shameerali.kolothum.thodi@huawei.com \
    --cc=yi.l.liu@intel.com \
    --cc=zhukeqian1@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.