Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 515 insertions, 0 deletions

diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
new file mode 100644
index 000000000..e9fa22d31
--- /dev/null
+++ b/drivers/infiniband/core/umem_odp.c
@@ -0,0 +1,515 @@
+/*
+ * Copyright (c) 2014 Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * 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.
+ */
+
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/task.h>
+#include <linux/pid.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/vmalloc.h>
+#include <linux/hugetlb.h>
+#include <linux/interval_tree.h>
+#include <linux/hmm.h>
+#include <linux/pagemap.h>
+
+#include <rdma/ib_umem_odp.h>
+
+#include "uverbs.h"
+
+static inline int ib_init_umem_odp(struct ib_umem_odp *umem_odp,
+				   const struct mmu_interval_notifier_ops *ops)
+{
+	int ret;
+
+	umem_odp->umem.is_odp = 1;
+	mutex_init(&umem_odp->umem_mutex);
+
+	if (!umem_odp->is_implicit_odp) {
+		size_t page_size = 1UL << umem_odp->page_shift;
+		unsigned long start;
+		unsigned long end;
+		size_t ndmas, npfns;
+
+		start = ALIGN_DOWN(umem_odp->umem.address, page_size);
+		if (check_add_overflow(umem_odp->umem.address,
+				       (unsigned long)umem_odp->umem.length,
+				       &end))
+			return -EOVERFLOW;
+		end = ALIGN(end, page_size);
+		if (unlikely(end < page_size))
+			return -EOVERFLOW;
+
+		ndmas = (end - start) >> umem_odp->page_shift;
+		if (!ndmas)
+			return -EINVAL;
+
+		npfns = (end - start) >> PAGE_SHIFT;
+		umem_odp->pfn_list = kvcalloc(
+			npfns, sizeof(*umem_odp->pfn_list), GFP_KERNEL);
+		if (!umem_odp->pfn_list)
+			return -ENOMEM;
+
+		umem_odp->dma_list = kvcalloc(
+			ndmas, sizeof(*umem_odp->dma_list), GFP_KERNEL);
+		if (!umem_odp->dma_list) {
+			ret = -ENOMEM;
+			goto out_pfn_list;
+		}
+
+		ret = mmu_interval_notifier_insert(&umem_odp->notifier,
+						   umem_odp->umem.owning_mm,
+						   start, end - start, ops);
+		if (ret)
+			goto out_dma_list;
+	}
+
+	return 0;
+
+out_dma_list:
+	kvfree(umem_odp->dma_list);
+out_pfn_list:
+	kvfree(umem_odp->pfn_list);
+	return ret;
+}
+
+/**
+ * ib_umem_odp_alloc_implicit - Allocate a parent implicit ODP umem
+ *
+ * Implicit ODP umems do not have a VA range and do not have any page lists.
+ * They exist only to hold the per_mm reference to help the driver create
+ * children umems.
+ *
+ * @device: IB device to create UMEM
+ * @access: ib_reg_mr access flags
+ */
+struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_device *device,
+					       int access)
+{
+	struct ib_umem *umem;
+	struct ib_umem_odp *umem_odp;
+	int ret;
+
+	if (access & IB_ACCESS_HUGETLB)
+		return ERR_PTR(-EINVAL);
+
+	umem_odp = kzalloc(sizeof(*umem_odp), GFP_KERNEL);
+	if (!umem_odp)
+		return ERR_PTR(-ENOMEM);
+	umem = &umem_odp->umem;
+	umem->ibdev = device;
+	umem->writable = ib_access_writable(access);
+	umem->owning_mm = current->mm;
+	umem_odp->is_implicit_odp = 1;
+	umem_odp->page_shift = PAGE_SHIFT;
+
+	umem_odp->tgid = get_task_pid(current->group_leader, PIDTYPE_PID);
+	ret = ib_init_umem_odp(umem_odp, NULL);
+	if (ret) {
+		put_pid(umem_odp->tgid);
+		kfree(umem_odp);
+		return ERR_PTR(ret);
+	}
+	return umem_odp;
+}
+EXPORT_SYMBOL(ib_umem_odp_alloc_implicit);
+
+/**
+ * ib_umem_odp_alloc_child - Allocate a child ODP umem under an implicit
+ *                           parent ODP umem
+ *
+ * @root: The parent umem enclosing the child. This must be allocated using
+ *        ib_alloc_implicit_odp_umem()
+ * @addr: The starting userspace VA
+ * @size: The length of the userspace VA
+ * @ops: MMU interval ops, currently only @invalidate
+ */
+struct ib_umem_odp *
+ib_umem_odp_alloc_child(struct ib_umem_odp *root, unsigned long addr,
+			size_t size,
+			const struct mmu_interval_notifier_ops *ops)
+{
+	/*
+	 * Caller must ensure that root cannot be freed during the call to
+	 * ib_alloc_odp_umem.
+	 */
+	struct ib_umem_odp *odp_data;
+	struct ib_umem *umem;
+	int ret;
+
+	if (WARN_ON(!root->is_implicit_odp))
+		return ERR_PTR(-EINVAL);
+
+	odp_data = kzalloc(sizeof(*odp_data), GFP_KERNEL);
+	if (!odp_data)
+		return ERR_PTR(-ENOMEM);
+	umem = &odp_data->umem;
+	umem->ibdev = root->umem.ibdev;
+	umem->length     = size;
+	umem->address    = addr;
+	umem->writable   = root->umem.writable;
+	umem->owning_mm  = root->umem.owning_mm;
+	odp_data->page_shift = PAGE_SHIFT;
+	odp_data->notifier.ops = ops;
+
+	/*
+	 * A mmget must be held when registering a notifier, the owming_mm only
+	 * has a mm_grab at this point.
+	 */
+	if (!mmget_not_zero(umem->owning_mm)) {
+		ret = -EFAULT;
+		goto out_free;
+	}
+
+	odp_data->tgid = get_pid(root->tgid);
+	ret = ib_init_umem_odp(odp_data, ops);
+	if (ret)
+		goto out_tgid;
+	mmput(umem->owning_mm);
+	return odp_data;
+
+out_tgid:
+	put_pid(odp_data->tgid);
+	mmput(umem->owning_mm);
+out_free:
+	kfree(odp_data);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(ib_umem_odp_alloc_child);
+
+/**
+ * ib_umem_odp_get - Create a umem_odp for a userspace va
+ *
+ * @device: IB device struct to get UMEM
+ * @addr: userspace virtual address to start at
+ * @size: length of region to pin
+ * @access: IB_ACCESS_xxx flags for memory being pinned
+ * @ops: MMU interval ops, currently only @invalidate
+ *
+ * The driver should use when the access flags indicate ODP memory. It avoids
+ * pinning, instead, stores the mm for future page fault handling in
+ * conjunction with MMU notifiers.
+ */
+struct ib_umem_odp *ib_umem_odp_get(struct ib_device *device,
+				    unsigned long addr, size_t size, int access,
+				    const struct mmu_interval_notifier_ops *ops)
+{
+	struct ib_umem_odp *umem_odp;
+	int ret;
+
+	if (WARN_ON_ONCE(!(access & IB_ACCESS_ON_DEMAND)))
+		return ERR_PTR(-EINVAL);
+
+	umem_odp = kzalloc(sizeof(struct ib_umem_odp), GFP_KERNEL);
+	if (!umem_odp)
+		return ERR_PTR(-ENOMEM);
+
+	umem_odp->umem.ibdev = device;
+	umem_odp->umem.length = size;
+	umem_odp->umem.address = addr;
+	umem_odp->umem.writable = ib_access_writable(access);
+	umem_odp->umem.owning_mm = current->mm;
+	umem_odp->notifier.ops = ops;
+
+	umem_odp->page_shift = PAGE_SHIFT;
+#ifdef CONFIG_HUGETLB_PAGE
+	if (access & IB_ACCESS_HUGETLB)
+		umem_odp->page_shift = HPAGE_SHIFT;
+#endif
+
+	umem_odp->tgid = get_task_pid(current->group_leader, PIDTYPE_PID);
+	ret = ib_init_umem_odp(umem_odp, ops);
+	if (ret)
+		goto err_put_pid;
+	return umem_odp;
+
+err_put_pid:
+	put_pid(umem_odp->tgid);
+	kfree(umem_odp);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(ib_umem_odp_get);
+
+void ib_umem_odp_release(struct ib_umem_odp *umem_odp)
+{
+	/*
+	 * Ensure that no more pages are mapped in the umem.
+	 *
+	 * It is the driver's responsibility to ensure, before calling us,
+	 * that the hardware will not attempt to access the MR any more.
+	 */
+	if (!umem_odp->is_implicit_odp) {
+		mutex_lock(&umem_odp->umem_mutex);
+		ib_umem_odp_unmap_dma_pages(umem_odp, ib_umem_start(umem_odp),
+					    ib_umem_end(umem_odp));
+		mutex_unlock(&umem_odp->umem_mutex);
+		mmu_interval_notifier_remove(&umem_odp->notifier);
+		kvfree(umem_odp->dma_list);
+		kvfree(umem_odp->pfn_list);
+	}
+	put_pid(umem_odp->tgid);
+	kfree(umem_odp);
+}
+EXPORT_SYMBOL(ib_umem_odp_release);
+
+/*
+ * Map for DMA and insert a single page into the on-demand paging page tables.
+ *
+ * @umem: the umem to insert the page to.
+ * @dma_index: index in the umem to add the dma to.
+ * @page: the page struct to map and add.
+ * @access_mask: access permissions needed for this page.
+ *
+ * The function returns -EFAULT if the DMA mapping operation fails.
+ *
+ */
+static int ib_umem_odp_map_dma_single_page(
+		struct ib_umem_odp *umem_odp,
+		unsigned int dma_index,
+		struct page *page,
+		u64 access_mask)
+{
+	struct ib_device *dev = umem_odp->umem.ibdev;
+	dma_addr_t *dma_addr = &umem_odp->dma_list[dma_index];
+
+	if (*dma_addr) {
+		/*
+		 * If the page is already dma mapped it means it went through
+		 * a non-invalidating trasition, like read-only to writable.
+		 * Resync the flags.
+		 */
+		*dma_addr = (*dma_addr & ODP_DMA_ADDR_MASK) | access_mask;
+		return 0;
+	}
+
+	*dma_addr = ib_dma_map_page(dev, page, 0, 1 << umem_odp->page_shift,
+				    DMA_BIDIRECTIONAL);
+	if (ib_dma_mapping_error(dev, *dma_addr)) {
+		*dma_addr = 0;
+		return -EFAULT;
+	}
+	umem_odp->npages++;
+	*dma_addr |= access_mask;
+	return 0;
+}
+
+/**
+ * ib_umem_odp_map_dma_and_lock - DMA map userspace memory in an ODP MR and lock it.
+ *
+ * Maps the range passed in the argument to DMA addresses.
+ * The DMA addresses of the mapped pages is updated in umem_odp->dma_list.
+ * Upon success the ODP MR will be locked to let caller complete its device
+ * page table update.
+ *
+ * Returns the number of pages mapped in success, negative error code
+ * for failure.
+ * @umem_odp: the umem to map and pin
+ * @user_virt: the address from which we need to map.
+ * @bcnt: the minimal number of bytes to pin and map. The mapping might be
+ *        bigger due to alignment, and may also be smaller in case of an error
+ *        pinning or mapping a page. The actual pages mapped is returned in
+ *        the return value.
+ * @access_mask: bit mask of the requested access permissions for the given
+ *               range.
+ * @fault: is faulting required for the given range
+ */
+int ib_umem_odp_map_dma_and_lock(struct ib_umem_odp *umem_odp, u64 user_virt,
+				 u64 bcnt, u64 access_mask, bool fault)
+			__acquires(&umem_odp->umem_mutex)
+{
+	struct task_struct *owning_process  = NULL;
+	struct mm_struct *owning_mm = umem_odp->umem.owning_mm;
+	int pfn_index, dma_index, ret = 0, start_idx;
+	unsigned int page_shift, hmm_order, pfn_start_idx;
+	unsigned long num_pfns, current_seq;
+	struct hmm_range range = {};
+	unsigned long timeout;
+
+	if (access_mask == 0)
+		return -EINVAL;
+
+	if (user_virt < ib_umem_start(umem_odp) ||
+	    user_virt + bcnt > ib_umem_end(umem_odp))
+		return -EFAULT;
+
+	page_shift = umem_odp->page_shift;
+
+	/*
+	 * owning_process is allowed to be NULL, this means somehow the mm is
+	 * existing beyond the lifetime of the originating process.. Presumably
+	 * mmget_not_zero will fail in this case.
+	 */
+	owning_process = get_pid_task(umem_odp->tgid, PIDTYPE_PID);
+	if (!owning_process || !mmget_not_zero(owning_mm)) {
+		ret = -EINVAL;
+		goto out_put_task;
+	}
+
+	range.notifier = &umem_odp->notifier;
+	range.start = ALIGN_DOWN(user_virt, 1UL << page_shift);
+	range.end = ALIGN(user_virt + bcnt, 1UL << page_shift);
+	pfn_start_idx = (range.start - ib_umem_start(umem_odp)) >> PAGE_SHIFT;
+	num_pfns = (range.end - range.start) >> PAGE_SHIFT;
+	if (fault) {
+		range.default_flags = HMM_PFN_REQ_FAULT;
+
+		if (access_mask & ODP_WRITE_ALLOWED_BIT)
+			range.default_flags |= HMM_PFN_REQ_WRITE;
+	}
+
+	range.hmm_pfns = &(umem_odp->pfn_list[pfn_start_idx]);
+	timeout = jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT);
+
+retry:
+	current_seq = range.notifier_seq =
+		mmu_interval_read_begin(&umem_odp->notifier);
+
+	mmap_read_lock(owning_mm);
+	ret = hmm_range_fault(&range);
+	mmap_read_unlock(owning_mm);
+	if (unlikely(ret)) {
+		if (ret == -EBUSY && !time_after(jiffies, timeout))
+			goto retry;
+		goto out_put_mm;
+	}
+
+	start_idx = (range.start - ib_umem_start(umem_odp)) >> page_shift;
+	dma_index = start_idx;
+
+	mutex_lock(&umem_odp->umem_mutex);
+	if (mmu_interval_read_retry(&umem_odp->notifier, current_seq)) {
+		mutex_unlock(&umem_odp->umem_mutex);
+		goto retry;
+	}
+
+	for (pfn_index = 0; pfn_index < num_pfns;
+		pfn_index += 1 << (page_shift - PAGE_SHIFT), dma_index++) {
+
+		if (fault) {
+			/*
+			 * Since we asked for hmm_range_fault() to populate
+			 * pages it shouldn't return an error entry on success.
+			 */
+			WARN_ON(range.hmm_pfns[pfn_index] & HMM_PFN_ERROR);
+			WARN_ON(!(range.hmm_pfns[pfn_index] & HMM_PFN_VALID));
+		} else {
+			if (!(range.hmm_pfns[pfn_index] & HMM_PFN_VALID)) {
+				WARN_ON(umem_odp->dma_list[dma_index]);
+				continue;
+			}
+			access_mask = ODP_READ_ALLOWED_BIT;
+			if (range.hmm_pfns[pfn_index] & HMM_PFN_WRITE)
+				access_mask |= ODP_WRITE_ALLOWED_BIT;
+		}
+
+		hmm_order = hmm_pfn_to_map_order(range.hmm_pfns[pfn_index]);
+		/* If a hugepage was detected and ODP wasn't set for, the umem
+		 * page_shift will be used, the opposite case is an error.
+		 */
+		if (hmm_order + PAGE_SHIFT < page_shift) {
+			ret = -EINVAL;
+			ibdev_dbg(umem_odp->umem.ibdev,
+				  "%s: un-expected hmm_order %u, page_shift %u\n",
+				  __func__, hmm_order, page_shift);
+			break;
+		}
+
+		ret = ib_umem_odp_map_dma_single_page(
+				umem_odp, dma_index, hmm_pfn_to_page(range.hmm_pfns[pfn_index]),
+				access_mask);
+		if (ret < 0) {
+			ibdev_dbg(umem_odp->umem.ibdev,
+				  "ib_umem_odp_map_dma_single_page failed with error %d\n", ret);
+			break;
+		}
+	}
+	/* upon success lock should stay on hold for the callee */
+	if (!ret)
+		ret = dma_index - start_idx;
+	else
+		mutex_unlock(&umem_odp->umem_mutex);
+
+out_put_mm:
+	mmput_async(owning_mm);
+out_put_task:
+	if (owning_process)
+		put_task_struct(owning_process);
+	return ret;
+}
+EXPORT_SYMBOL(ib_umem_odp_map_dma_and_lock);
+
+void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 virt,
+				 u64 bound)
+{
+	dma_addr_t dma_addr;
+	dma_addr_t dma;
+	int idx;
+	u64 addr;
+	struct ib_device *dev = umem_odp->umem.ibdev;
+
+	lockdep_assert_held(&umem_odp->umem_mutex);
+
+	virt = max_t(u64, virt, ib_umem_start(umem_odp));
+	bound = min_t(u64, bound, ib_umem_end(umem_odp));
+	for (addr = virt; addr < bound; addr += BIT(umem_odp->page_shift)) {
+		idx = (addr - ib_umem_start(umem_odp)) >> umem_odp->page_shift;
+		dma = umem_odp->dma_list[idx];
+
+		/* The access flags guaranteed a valid DMA address in case was NULL */
+		if (dma) {
+			unsigned long pfn_idx = (addr - ib_umem_start(umem_odp)) >> PAGE_SHIFT;
+			struct page *page = hmm_pfn_to_page(umem_odp->pfn_list[pfn_idx]);
+
+			dma_addr = dma & ODP_DMA_ADDR_MASK;
+			ib_dma_unmap_page(dev, dma_addr,
+					  BIT(umem_odp->page_shift),
+					  DMA_BIDIRECTIONAL);
+			if (dma & ODP_WRITE_ALLOWED_BIT) {
+				struct page *head_page = compound_head(page);
+				/*
+				 * set_page_dirty prefers being called with
+				 * the page lock. However, MMU notifiers are
+				 * called sometimes with and sometimes without
+				 * the lock. We rely on the umem_mutex instead
+				 * to prevent other mmu notifiers from
+				 * continuing and allowing the page mapping to
+				 * be removed.
+				 */
+				set_page_dirty(head_page);
+			}
+			umem_odp->dma_list[idx] = 0;
+			umem_odp->npages--;
+		}
+	}
+}
+EXPORT_SYMBOL(ib_umem_odp_unmap_dma_pages);