--- /dev/null
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * Intel SCIF driver.
+ *
+ */
+#include "scif_main.h"
+#include <linux/mmu_notifier.h>
+#include <linux/highmem.h>
+
+/*
+ * scif_insert_tcw:
+ *
+ * Insert a temp window to the temp registration list sorted by va_for_temp.
+ * RMA lock must be held.
+ */
+void scif_insert_tcw(struct scif_window *window, struct list_head *head)
+{
+ struct scif_window *curr = NULL;
+ struct scif_window *prev = list_entry(head, struct scif_window, list);
+ struct list_head *item;
+
+ INIT_LIST_HEAD(&window->list);
+ /* Compare with tail and if the entry is new tail add it to the end */
+ if (!list_empty(head)) {
+ curr = list_entry(head->prev, struct scif_window, list);
+ if (curr->va_for_temp < window->va_for_temp) {
+ list_add_tail(&window->list, head);
+ return;
+ }
+ }
+ list_for_each(item, head) {
+ curr = list_entry(item, struct scif_window, list);
+ if (curr->va_for_temp > window->va_for_temp)
+ break;
+ prev = curr;
+ }
+ list_add(&window->list, &prev->list);
+}
+
+/*
+ * scif_insert_window:
+ *
+ * Insert a window to the self registration list sorted by offset.
+ * RMA lock must be held.
+ */
+void scif_insert_window(struct scif_window *window, struct list_head *head)
+{
+ struct scif_window *curr = NULL, *prev = NULL;
+ struct list_head *item;
+
+ INIT_LIST_HEAD(&window->list);
+ list_for_each(item, head) {
+ curr = list_entry(item, struct scif_window, list);
+ if (curr->offset > window->offset)
+ break;
+ prev = curr;
+ }
+ if (!prev)
+ list_add(&window->list, head);
+ else
+ list_add(&window->list, &prev->list);
+ scif_set_window_ref(window, window->nr_pages);
+}
+
+/*
+ * scif_query_tcw:
+ *
+ * Query the temp cached registration list of ep for an overlapping window
+ * in case of permission mismatch, destroy the previous window. if permissions
+ * match and overlap is partial, destroy the window but return the new range
+ * RMA lock must be held.
+ */
+int scif_query_tcw(struct scif_endpt *ep, struct scif_rma_req *req)
+{
+ struct list_head *item, *temp, *head = req->head;
+ struct scif_window *window;
+ u64 start_va_window, start_va_req = req->va_for_temp;
+ u64 end_va_window, end_va_req = start_va_req + req->nr_bytes;
+
+ if (!req->nr_bytes)
+ return -EINVAL;
+ /*
+ * Avoid traversing the entire list to find out that there
+ * is no entry that matches
+ */
+ if (!list_empty(head)) {
+ window = list_last_entry(head, struct scif_window, list);
+ end_va_window = window->va_for_temp +
+ (window->nr_pages << PAGE_SHIFT);
+ if (start_va_req > end_va_window)
+ return -ENXIO;
+ }
+ list_for_each_safe(item, temp, head) {
+ window = list_entry(item, struct scif_window, list);
+ start_va_window = window->va_for_temp;
+ end_va_window = window->va_for_temp +
+ (window->nr_pages << PAGE_SHIFT);
+ if (start_va_req < start_va_window &&
+ end_va_req < start_va_window)
+ break;
+ if (start_va_req >= end_va_window)
+ continue;
+ if ((window->prot & req->prot) == req->prot) {
+ if (start_va_req >= start_va_window &&
+ end_va_req <= end_va_window) {
+ *req->out_window = window;
+ return 0;
+ }
+ /* expand window */
+ if (start_va_req < start_va_window) {
+ req->nr_bytes +=
+ start_va_window - start_va_req;
+ req->va_for_temp = start_va_window;
+ }
+ if (end_va_req >= end_va_window)
+ req->nr_bytes += end_va_window - end_va_req;
+ }
+ /* Destroy the old window to create a new one */
+ __scif_rma_destroy_tcw_helper(window);
+ break;
+ }
+ return -ENXIO;
+}
+
+/*
+ * scif_query_window:
+ *
+ * Query the registration list and check if a valid contiguous
+ * range of windows exist.
+ * RMA lock must be held.
+ */
+int scif_query_window(struct scif_rma_req *req)
+{
+ struct list_head *item;
+ struct scif_window *window;
+ s64 end_offset, offset = req->offset;
+ u64 tmp_min, nr_bytes_left = req->nr_bytes;
+
+ if (!req->nr_bytes)
+ return -EINVAL;
+
+ list_for_each(item, req->head) {
+ window = list_entry(item, struct scif_window, list);
+ end_offset = window->offset +
+ (window->nr_pages << PAGE_SHIFT);
+ if (offset < window->offset)
+ /* Offset not found! */
+ return -ENXIO;
+ if (offset >= end_offset)
+ continue;
+ /* Check read/write protections. */
+ if ((window->prot & req->prot) != req->prot)
+ return -EPERM;
+ if (nr_bytes_left == req->nr_bytes)
+ /* Store the first window */
+ *req->out_window = window;
+ tmp_min = min((u64)end_offset - offset, nr_bytes_left);
+ nr_bytes_left -= tmp_min;
+ offset += tmp_min;
+ /*
+ * Range requested encompasses
+ * multiple windows contiguously.
+ */
+ if (!nr_bytes_left) {
+ /* Done for partial window */
+ if (req->type == SCIF_WINDOW_PARTIAL ||
+ req->type == SCIF_WINDOW_SINGLE)
+ return 0;
+ /* Extra logic for full windows */
+ if (offset == end_offset)
+ /* Spanning multiple whole windows */
+ return 0;
+ /* Not spanning multiple whole windows */
+ return -ENXIO;
+ }
+ if (req->type == SCIF_WINDOW_SINGLE)
+ break;
+ }
+ dev_err(scif_info.mdev.this_device,
+ "%s %d ENXIO\n", __func__, __LINE__);
+ return -ENXIO;
+}
+
+/*
+ * scif_rma_list_unregister:
+ *
+ * Traverse the self registration list starting from window:
+ * 1) Call scif_unregister_window(..)
+ * RMA lock must be held.
+ */
+int scif_rma_list_unregister(struct scif_window *window,
+ s64 offset, int nr_pages)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)window->ep;
+ struct list_head *head = &ep->rma_info.reg_list;
+ s64 end_offset;
+ int err = 0;
+ int loop_nr_pages;
+ struct scif_window *_window;
+
+ list_for_each_entry_safe_from(window, _window, head, list) {
+ end_offset = window->offset + (window->nr_pages << PAGE_SHIFT);
+ loop_nr_pages = min((int)((end_offset - offset) >> PAGE_SHIFT),
+ nr_pages);
+ err = scif_unregister_window(window);
+ if (err)
+ return err;
+ nr_pages -= loop_nr_pages;
+ offset += (loop_nr_pages << PAGE_SHIFT);
+ if (!nr_pages)
+ break;
+ }
+ return 0;
+}
+
+/*
+ * scif_unmap_all_window:
+ *
+ * Traverse all the windows in the self registration list and:
+ * 1) Delete any DMA mappings created
+ */
+void scif_unmap_all_windows(scif_epd_t epd)
+{
+ struct list_head *item, *tmp;
+ struct scif_window *window;
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ struct list_head *head = &ep->rma_info.reg_list;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ list_for_each_safe(item, tmp, head) {
+ window = list_entry(item, struct scif_window, list);
+ scif_unmap_window(ep->remote_dev, window);
+ }
+ mutex_unlock(&ep->rma_info.rma_lock);
+}
+
+/*
+ * scif_unregister_all_window:
+ *
+ * Traverse all the windows in the self registration list and:
+ * 1) Call scif_unregister_window(..)
+ * RMA lock must be held.
+ */
+int scif_unregister_all_windows(scif_epd_t epd)
+{
+ struct list_head *item, *tmp;
+ struct scif_window *window;
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ struct list_head *head = &ep->rma_info.reg_list;
+ int err = 0;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+retry:
+ item = NULL;
+ tmp = NULL;
+ list_for_each_safe(item, tmp, head) {
+ window = list_entry(item, struct scif_window, list);
+ ep->rma_info.async_list_del = 0;
+ err = scif_unregister_window(window);
+ if (err)
+ dev_err(scif_info.mdev.this_device,
+ "%s %d err %d\n",
+ __func__, __LINE__, err);
+ /*
+ * Need to restart list traversal if there has been
+ * an asynchronous list entry deletion.
+ */
+ if (ACCESS_ONCE(ep->rma_info.async_list_del))
+ goto retry;
+ }
+ mutex_unlock(&ep->rma_info.rma_lock);
+ if (!list_empty(&ep->rma_info.mmn_list)) {
+ spin_lock(&scif_info.rmalock);
+ list_add_tail(&ep->mmu_list, &scif_info.mmu_notif_cleanup);
+ spin_unlock(&scif_info.rmalock);
+ schedule_work(&scif_info.mmu_notif_work);
+ }
+ return err;
+}
Code Review / kvmfornfv.git / blobdiff