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Diffstat (limited to 'drivers/misc/ocxl/pasid.c')
-rw-r--r--drivers/misc/ocxl/pasid.c107
1 files changed, 107 insertions, 0 deletions
diff --git a/drivers/misc/ocxl/pasid.c b/drivers/misc/ocxl/pasid.c
new file mode 100644
index 0000000000..d14cb56e69
--- /dev/null
+++ b/drivers/misc/ocxl/pasid.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright 2017 IBM Corp.
+#include "ocxl_internal.h"
+
+
+struct id_range {
+ struct list_head list;
+ u32 start;
+ u32 end;
+};
+
+#ifdef DEBUG
+static void dump_list(struct list_head *head, char *type_str)
+{
+ struct id_range *cur;
+
+ pr_debug("%s ranges allocated:\n", type_str);
+ list_for_each_entry(cur, head, list) {
+ pr_debug("Range %d->%d\n", cur->start, cur->end);
+ }
+}
+#endif
+
+static int range_alloc(struct list_head *head, u32 size, int max_id,
+ char *type_str)
+{
+ struct list_head *pos;
+ struct id_range *cur, *new;
+ int rc, last_end;
+
+ new = kmalloc(sizeof(struct id_range), GFP_KERNEL);
+ if (!new)
+ return -ENOMEM;
+
+ pos = head;
+ last_end = -1;
+ list_for_each_entry(cur, head, list) {
+ if ((cur->start - last_end) > size)
+ break;
+ last_end = cur->end;
+ pos = &cur->list;
+ }
+
+ new->start = last_end + 1;
+ new->end = new->start + size - 1;
+
+ if (new->end > max_id) {
+ kfree(new);
+ rc = -ENOSPC;
+ } else {
+ list_add(&new->list, pos);
+ rc = new->start;
+ }
+
+#ifdef DEBUG
+ dump_list(head, type_str);
+#endif
+ return rc;
+}
+
+static void range_free(struct list_head *head, u32 start, u32 size,
+ char *type_str)
+{
+ bool found = false;
+ struct id_range *cur, *tmp;
+
+ list_for_each_entry_safe(cur, tmp, head, list) {
+ if (cur->start == start && cur->end == (start + size - 1)) {
+ found = true;
+ list_del(&cur->list);
+ kfree(cur);
+ break;
+ }
+ }
+ WARN_ON(!found);
+#ifdef DEBUG
+ dump_list(head, type_str);
+#endif
+}
+
+int ocxl_pasid_afu_alloc(struct ocxl_fn *fn, u32 size)
+{
+ int max_pasid;
+
+ if (fn->config.max_pasid_log < 0)
+ return -ENOSPC;
+ max_pasid = 1 << fn->config.max_pasid_log;
+ return range_alloc(&fn->pasid_list, size, max_pasid, "afu pasid");
+}
+
+void ocxl_pasid_afu_free(struct ocxl_fn *fn, u32 start, u32 size)
+{
+ return range_free(&fn->pasid_list, start, size, "afu pasid");
+}
+
+int ocxl_actag_afu_alloc(struct ocxl_fn *fn, u32 size)
+{
+ int max_actag;
+
+ max_actag = fn->actag_enabled;
+ return range_alloc(&fn->actag_list, size, max_actag, "afu actag");
+}
+
+void ocxl_actag_afu_free(struct ocxl_fn *fn, u32 start, u32 size)
+{
+ return range_free(&fn->actag_list, start, size, "afu actag");
+}