1 files changed, 84 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/hfi1/user_pages.c b/drivers/infiniband/hw/hfi1/user_pages.c
new file mode 100644
index 000000000..7bce963e2
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/user_pages.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+/*
+ * Copyright(c) 2015-2017 Intel Corporation.
+ */
+
+#include <linux/mm.h>
+#include <linux/sched/signal.h>
+#include <linux/device.h>
+#include <linux/module.h>
+
+#include "hfi.h"
+
+static unsigned long cache_size = 256;
+module_param(cache_size, ulong, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(cache_size, "Send and receive side cache size limit (in MB)");
+
+/*
+ * Determine whether the caller can pin pages.
+ *
+ * This function should be used in the implementation of buffer caches.
+ * The cache implementation should call this function prior to attempting
+ * to pin buffer pages in order to determine whether they should do so.
+ * The function computes cache limits based on the configured ulimit and
+ * cache size. Use of this function is especially important for caches
+ * which are not limited in any other way (e.g. by HW resources) and, thus,
+ * could keeping caching buffers.
+ *
+ */
+bool hfi1_can_pin_pages(struct hfi1_devdata *dd, struct mm_struct *mm,
+			u32 nlocked, u32 npages)
+{
+	unsigned long ulimit = rlimit(RLIMIT_MEMLOCK), pinned, cache_limit,
+		size = (cache_size * (1UL << 20)); /* convert to bytes */
+	unsigned int usr_ctxts =
+			dd->num_rcv_contexts - dd->first_dyn_alloc_ctxt;
+	bool can_lock = capable(CAP_IPC_LOCK);
+
+	/*
+	 * Calculate per-cache size. The calculation below uses only a quarter
+	 * of the available per-context limit. This leaves space for other
+	 * pinning. Should we worry about shared ctxts?
+	 */
+	cache_limit = (ulimit / usr_ctxts) / 4;
+
+	/* If ulimit isn't set to "unlimited" and is smaller than cache_size. */
+	if (ulimit != (-1UL) && size > cache_limit)
+		size = cache_limit;
+
+	/* Convert to number of pages */
+	size = DIV_ROUND_UP(size, PAGE_SIZE);
+
+	pinned = atomic64_read(&mm->pinned_vm);
+
+	/* First, check the absolute limit against all pinned pages. */
+	if (pinned + npages >= ulimit && !can_lock)
+		return false;
+
+	return ((nlocked + npages) <= size) || can_lock;
+}
+
+int hfi1_acquire_user_pages(struct mm_struct *mm, unsigned long vaddr, size_t npages,
+			    bool writable, struct page **pages)
+{
+	int ret;
+	unsigned int gup_flags = FOLL_LONGTERM | (writable ? FOLL_WRITE : 0);
+
+	ret = pin_user_pages_fast(vaddr, npages, gup_flags, pages);
+	if (ret < 0)
+		return ret;
+
+	atomic64_add(ret, &mm->pinned_vm);
+
+	return ret;
+}
+
+void hfi1_release_user_pages(struct mm_struct *mm, struct page **p,
+			     size_t npages, bool dirty)
+{
+	unpin_user_pages_dirty_lock(p, npages, dirty);
+
+	if (mm) { /* during close after signal, mm can be NULL */
+		atomic64_sub(npages, &mm->pinned_vm);
+	}
+}